A catalogue of AGN observed by the PDS experiment on board BeppoSAX

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与古文物有关的英语作文

When delving into the realm of ancient artifacts, one cannot help but be captivated by the stories they tell, the civilizations they represent, and the mysteries they continue to hold. The study of antiquities, or antiquities, is a field that bridges archaeology, history, and art, offering a unique perspective on the past.The Significance of AntiquitiesAntiquities are remnants of past civilizations, often unearthed through archaeological excavations. They are significant for several reasons:1. Cultural Heritage: Antiquities serve as a tangible connection to our ancestors, offering insights into their daily lives, beliefs, and social structures. They are a testament to the ingenuity and creativity of ancient cultures.2. Historical Understanding: They provide a more nuanced understanding of history, often filling in gaps left by written records. For instance, the Rosetta Stone, discovered in 1799, was instrumental in deciphering Egyptian hieroglyphs, opening up a new understanding of ancient Egyptian culture.3. Artistic Value: Many antiquities are works of art, showcasing the aesthetic sensibilities and technical skills of their creators. The sculptures of ancient Greece, the pottery of the Chinese dynasties, and the intricate carvings of the Mayan civilization are just a few examples.Preservation and ConservationThe preservation and conservation of antiquities are critical to ensure their survival for future generations. This involves:1. Restoration: Careful restoration work is often necessary to repair damage caused by time, environmental factors, or improper handling. This requires specialized knowledge and techniques to avoid further damage.2. Storage: Antiquities must be stored in conditions that control temperature, humidity, and light exposure to prevent deterioration.3. Security: Given their value, both monetary and cultural, antiquities require robust security measures to protect them from theft and vandalism.Ethical ConsiderationsThe field of antiquities is not without its ethical dilemmas. Issues such as looting, illegal trafficking, and the repatriation of cultural property are ongoing concerns. Ethical practices in archaeology and the handling of antiquities include:1. Respect for Cultural Property: It is important to respect the cultural significance of antiquities and to work with local communities and governments to ensure their proper treatment.2. Legal Compliance: Adhering to international laws and treaties that govern the excavation, trade, and display of antiquities is crucial to prevent the loss of cultural heritage.3. Transparency: Clear documentation and provenance of antiquities help to ensure their legitimate acquisition and prevent the circulation of stolen artifacts.The Role of TechnologyAdvancements in technology have greatly enhanced the study and preservation of antiquities. Techniques such as 3D scanning, digital reconstruction, and advanced imaging allow for detailed analysis and virtual preservation of artifacts without the need for physical handling.ConclusionAntiquities are more than mere objects they are windows into the past, offering a glimpse into the lives of those who came before us. As we continue to uncover and study these treasures, we enrich our understanding of human history and culture. It is our collective responsibility to preserve and respect these invaluable pieces of our shared heritage.。

20623-2006英文

20623-2006英文20623-2006 EnglishIn recent years, the world has seen an unprecedented development in technology and communication. With the increasing integration of global economies, international standards have become essential in ensuring harmonized practices and promoting trade. Standardization plays a crucial role in various industries, providing a framework for quality management and improving overall efficiency. One such standard that has gained significant importance is the 20623-2006 English standard.The 20623-2006 English standard is a comprehensive guideline for effective communication in English. It focuses on the use of language, grammar, and vocabulary in various professional and business contexts. This standard aims to enhance understanding, reduce miscommunication, and facilitate a smooth exchange of information among individuals from diverse cultural backgrounds.One of the key aspects covered in the 20623-2006 English standard is clarity in communication. The standard emphasizes the importance of using plain and simple language to convey messages. By avoiding jargon or complex sentence structures, the standard ensures that the intended meaning is clear to all parties involved. This clarity is especially critical in cross-cultural business negotiations or international conferences, where participants may have different levels of English proficiency.Furthermore, the 20623-2006 English standard addresses the issue of grammar and vocabulary. It provides guidelines for the correct usage oftenses, prepositions, and articles, among other grammatical elements. Additionally, the standard promotes the use of appropriate vocabulary, encouraging individuals to choose words that accurately convey their intended meaning. This attention to grammar and vocabulary helps to minimize misunderstandings and ensures effective communication between parties.In addition to clarity and grammar, the standard also emphasizes cultural sensitivity. It recognizes the diverse cultural backgrounds of individuals involved in international communication and encourages respect for cultural differences. Adhering to this standard means being aware of linguistic nuances, avoiding offensive language or stereotypes, and tailoring communication styles to suit the cultural sensitivities of the audience. This cultural sensitivity fosters better rapport and understanding between individuals, promoting effective collaboration and avoiding potential conflicts.The 20623-2006 English standard also emphasizes the importance of brevity and conciseness in communication. In a fast-paced business environment, time is a valuable resource. The standard encourages individuals to express their ideas and thoughts succinctly, avoiding unnecessary repetition or excessive use of words. By promoting brevity, the standard enables efficient communication, allowing for quicker decision-making and streamlined processes.Overall, the 20623-2006 English standard provides comprehensive guidelines for effective English communication in professional and business contexts. By focusing on clarity, grammar, vocabulary, cultural sensitivity,brevity, and conciseness, the standard ensures that communication is accurate, efficient, and culturally appropriate. Adhering to this standard enables individuals to better navigate the globalized world, promotes understanding among diverse cultures, and supports harmonized practices in the international business arena.In conclusion, the 20623-2006 English standard serves as a vital tool for effective communication in English. As technology continues to advance and global connections strengthen, the importance of standardized communication cannot be overstated. By following the guidelines outlined in this standard, individuals and organizations can ensure that their messages are accurately understood, fostering collaboration, and facilitating successful interactions in the international arena.。

2024年新课标全国ⅰ卷英语高考真题文档版(含答案)

2024年普通高等学校招生全国统一考试（新课标Ⅰ卷）英语学科姓名________________准考证号________________全卷共12页，满分150分，考试时间120分钟。

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1.【此处可播放相关音频，请去附件查看】What is Kate doing?A.Boarding a flight.B.Arranging a trip.C.Seeing a friend off.2.【此处可播放相关音频，请去附件查看】What are the speakers talking about?A.A pop star.B.An old song.C.A radio program.3.【此处可播放相关音频，请去附件查看】What will the speakers do today?A.Go to an art show.B.Meet the man's aunt.C.Eat out with Mark.4.【此处可播放相关音频，请去附件查看】What does the man want to do?A.Cancel an order.B.Ask for a receipt.C.Reschedule a delivery.5.【此处可播放相关音频，请去附件查看】When will the next train to Bedford leave?A.At9:45.B.At10:15.C.At11:00.第二节（共15小题；每小题1.5分，满分22.5分）听下面5段对话或独白。

研究生公共英语教材阅读B第3、4、10、11、14课文原文及翻译

Unite 3 Doctor’s Dilemma: Treat or Let Die?Abigail Trafford1. Medical advances in wonder drugs, daring surgical procedures, radiation therapies, and intensive-care units have brought new life to thousands of people. Yet to many of them, modern medicine has become a double-edged sword.2. Doctor’s power to treat with an array of space-age techniques has outstripped the body’s capacity to heal. More medical problems can be treated, but for many patients, there is little hope of recovery. Even the fundamental distinction between life and death has been blurred.3. Many Americans are caught in medical limbo, as was the South Korean boxer Duk Koo Kim, who was kept alive by artificial means after he had been knocked unconscious in a fight and his brain ceased to function. With the permission of his family, doctors in Las Vegas disconnected the life-support machines and death quickly followed.4. In the wake of technology’s advances in medicine, a heated debate is taking place in hospitals and nursing homes across the country --- over whether survival or quality of life is the paramount goal of medicine.5. “It gets down to what medicine is all about, ” says Daniel Callahan, director of the Institute of Society, Ethics, and the Life Sciences in Hastings-on-Hudson, New York. “Is it really to save a life? Or is the larger goal the welfare of the patient?”6. Doctors, patients, relatives, and often the courts are being forced to make hard choices in medicine. Most often it is at the two extremes of life that these difficultyethical questions arise --- at the beginning for the very sick newborn and at the end for the dying patient.7. The dilemma posed by modern medical technology has created the growing new discipline or bioethics. Many of the country’s 127 medical s chools now offer courses in medical ethics, a field virtually ignored only a decade ago. Many hospitals have chaplains, philosophers, psychiatrists, and social workers on the staff to help patients make crucial decisions, and one in twenty institutions has a special ethics committee to resolve difficult cases.Death and Dying8. Of all the patients in intensive-care units who are at risk of dying, some 20 percent present difficult ethical choices --- whether to keep trying to save the life or to pull back and let the patient die. In many units, decisions regarding life-sustaining care are made about three times a week.9. Even the definition of death has been changed. Now that the heart-lung machine can take over the functions of breathing and pumping blood, death no longer always comes with the patient’s “last gasp” or when the heart stops beating. Thirty-one states and the District of Columbia have passed brain-death statutes that identify death as when the whole brain ceases to function.10. More than a do zen states recognize “living wills” in which the patients leave instructions to doctors not to prolong life by feeding them intravenously or by other methods if their illness becomes hopeless. A survey of California doctors showed that 20 to 30 percent were following instructions of such wills. Meanwhile, the hospicemovement, which its emphasis on providing comfort --- not cure --- to the dying patient, has gained momentum in many areas.11. Despite progress in society’s understanding of death and dying, t heory issues remain. Example: A woman, 87, afflicted by the nervous-system disorder of Parkinson’s disease, has a massive stroke and is found unconscious by her family. Their choices are to put her in a nursing home until she dies or to send her to a medical center for diagnosis and possible treatment. The family opts for a teaching hospital in New York city. Tests show the woman’s stroke resulted from a blood clot that is curable with surgery. After the operation, she says to her family: “Why did you bring me back to this agony?” Her health continues to worsen, and two years later she dies.12. On the other hand, doctors say prognosis is often uncertain and that patients, just because they are old and disabled, should not be denied life-saving therapy. Ethicists also fear that under the guise of medical decision not to treat certain patients, death may become too easy, pushing the country toward the acceptance of euthanasia.13. For some people, the agony of watching high-technology dying is too great. Earlier this year, Woodrow Wilson Collums, a retired dairyman from Poteet, Texas, was put on probation for the mercy killing of his older brother Jim, who lay hopeless in his bed at a nursing home, a victim of severe senility resul ting from Alzheimer’s disease. After the killing, the victim’s widow said: “I think God, Jim’s out of his misery. I hate to think it had to be done the way it was done, but I understand it. ”Crisis in Newborn Care14. At the other end of the life span, technology has so revolutionized newborn carethat it is no longer clear when human life is viable outside the womb. Newborn care has got huge progress, so it is absolutely clear that human being can survive independently outside the womb. Twenty-five years ago, infants weighting less than three and one-half pounds rarely survived. The current survival rate is 70 percent, and doctors are “salvaging” some babies that weigh only one and one-half pounds. Tremendous progress has been made in treating birth deformities such as spina bifida. Just ten years ago, only 5 percent of infants with transposition of the great arteries --- the congenital heart defect most commonly found in newborns --- survived. Today, 50 percent live.15. Yet, for many infants who owe their lives to new medical advances, survival has come at a price. A significant number emerge with permanent physical and mental handicaps.16. “The question of treatment and nontreatment of seriously ill newborns is not a single one,”says Thomas Murray of the Hastings Center. “But I feel strongly that retardation or the fact that someone is going to be less than perfect is not good grounds for allowing an infant to die.”17. For many parents, however, the experience of having a sick newborn becomes a lingering nightmare. Two years ago, an Atlanta mother gave birth to a baby suffering from Down’s Syndrome, a form of mental retardation; the child also had blocked intestines. The doctors rejected the parents’ plea not to operate, and today the child, severely retarded, still suffers intestinal problems.18. “Every time Melanie has a bowel movement, she cries,” explains her mother.“She’s not able to take care of herself, and we won’t live forever. I wanted to save her from sorrow, pain, and suffering. I don’t understand the emphasis on life at all costs, and I’m very angry at the doctors and the hospital. Who will take care of Melanie after we’re gone? Where will you doctors be then?”Changing Standards19. The choices posed by modern technology have profoundly changed the practice of medicine. Until now, most doctors have been activists, trained to use all the tools in their medical arsenals to treat disease. The current trend is toward nontreatment as doctors grapple with questions not just of who should get care but when to take therapy away.20. Always in the background is the threat of legal action. In August, two California doctors were charged with murdering a comatose patient by allegedly disconnecting the respirator and cutting off food and water. In 1981, a Massachusetts nurse was charged with murdering a cancer patient with massive doses of morphine but was subsequently acquitted.21. Between lawsuits, government regulations, and patients’ rights, many doctors feel they are under siege. Modern technology actually has limited their ability to make choices. More recently, these actions are resolved by committees.Public Policy22. In recent years, the debate on medical ethics has moved to the level of national policy. “It’s just beginning to hit us that we don’t have unlimited resources,” says Washington Hospital Center’s Dr. Lynch. “You can’t talk about ethics without talkingethics without talking about money.”23. Since 1972. Americans have enjoyed unlimited access to a taxpayer-supported, kidney dialysis program that offers life-prolonging therapy to all patients with kidney failure. To a number of police analysts, the program has grown out of control --- to a $1.4billion operation supporting 61,000 patients. The majority are over 50, and about a quarter have other illness, such as cancer or heart disease, conditions that could exclude them from dialysis in other countries.24. Some hospitals are pulling back from certain lifesaving treatment. Massachusetts General Hospital, for example, has decided not perform heart transplants on the ground that the high costs of providing such surgery help too few patients. Burn units --- through extremely effective --- also provide very expensive therapy for very few patients.25. As medical scientists push back the frontiers of therapy, the moral dilemma will continue to grow for doctors and patients alike, making the choice of to treat the basic question in modern medicine.1. 在特效药、风险性手术进程、放疗法以及特护病房方面的医学进展已为数千人带来新生。

Remarks on monopoles in Abelian projected continuum Yang-Mills theories

a r X i v :h e p -t h /0112051v 1 6 D e c 20011Remarks on monopoles in Abelian projected continuum Yang-Mills theories ∗A.R.Fazio a S.P.Sorella baUniversit`a degli Studi di Milano and INFN,via Celoria 16,20143Milano,ItalybUERJ,Universidade do Estado do Rio de Janeiro Rua S˜a o Francisco Xavier 524,20550-013Maracan˜a ,Rio de Janeiro,BrazilA possible mechanism accounting for monopole conﬁgurations in continuum Yang-Mills theories is discussed.The presence of the gauge ﬁxing term is taken into account.1.IntroductionThe understanding of conﬁnement in non-abelian gauge theories is one of the major chal-lenge in theoretical physics.The idea that con-ﬁnement could be explained as a dual Meissner eﬀect for type II superconductors is largely ac-cepted,with conﬁrmations from lattice simula-tions.A key ingredient for the picture of dual super-conductivity is the mechanism of Abelian projec-tion introduced by ’t Hooft [1],which consists of reducing the gauge group SU (N )to an Abelian subgroup,identiﬁed with the Cartan subgroup U (1)N −1,by means of a partial gauge ﬁxing.This is achieved by choosing any local composite oper-ator X (x )which transforms in the adjoint rep-resentation,X ′(x )=UX (x )U †.The gauge is partially ﬁxed by requiring that X becomes di-agonal,X ′(x )=diag(λ1(x ),......,λN (x )),where λi (x )denote the gauge invariant eigenvalues.As shown in [1],monopoles conﬁgurations appear at the points x 0of the space-time where two eigen-values coincide,i.e.λi +1(x 0)=λi (x 0).Further,the gauge ﬁeld is decomposed into its diagonal and oﬀ-diagonal parts.The diagonal compo-nents correspond to the generators of the Car-tan subgroup and behave as photons.The oﬀ-diagonal components are charged with respect to the Abelian residual subgroup and may become massive [2,3],being not protected by gauge invari-ance.This mass should set the conﬁnement scale,allowing for the decoupling of the oﬀ-diagonal ﬁelds at low energy.The ﬁnal Abelian projected theory turns out thus to be described by an eﬀec-tive low-energy theory in which the relevant de-grees of freedom are identiﬁed with the diagonal components of the gauge ﬁelds and with a certain amount of monopoles,whose condensation should account for the conﬁnement of all chromoelectric ttice simulations [4,5]have provided evidences for the Abelian dominance hypothe-sis,according to which QCD in the low-energy regime is described by an eﬀective Abelian the-ory.This supports the realization of conﬁnement through a dual Meissner eﬀect,although the in-frared Abelian dominance in lattice calculations seems not to be a general feature of any Abelian gauge [6].Furthermore,many conceptual points remain to be clariﬁed in order to achieve a satis-factory understanding of conﬁnement in the con-tinuum.Certainly,the problem of the deriva-tion of the Abelian dominance from the QCD La-grangian is a crucial one.Also,the characteriza-tion of the eﬀective low-energy Abelian projected theory and of its monopoles content is of great relevance.There,one usually starts by impos-ing the so called Maximal Abelian Gauge (MAG)[7],which allows for a manifest residual subgroup U (1)N −1.The presence of monopoles in the MAG follows then from Π2(SU (N )/U (1)N −1)=Z N −1.However,being the MAG a gauge-ﬁxing condi-tion,it is manifestly noncovariant.Therefore,2monopoles here do not seem to be directly re-lated to the singularities occurring for coinciding eigenvalues in the process of diagonalization of a local covariant operator X (x ).Rather,they are associatedtosingular conﬁgurations of the ﬁelds [7].The purpose of this contribution is to discuss a possible mechanism accounting for the presence of monopoles in the MAG,for continuum gauge theories.The argument turns out to be general-ized to any renormalizable gauge,the main idea being that of showing that ’t Hooft Abelian pro-jection can be suitably carried out in the presence of gauge ﬁxing terms.2.Monopoles in quantized Yang-Mills the-ories In what follows we present a simple way in or-der to account for monopoles in continuum quan-tized Yang-Mills theories.In particular,we point out that it is possible to introduce in the path in-tegral a covariant local quantity whose diagonal-ization is compatible with the gauge ﬁxing,repro-ducing at the end the usual form of the Yang-Mills partition function in the presence of monopoles [7].Let us start by considering the partition func-tion for the quantized SU (N )Yang-Mills theoryZ =N[D Φ][DA ]exp − d 4x Tr14F µνF µν→Tri4B µνB µν(2)Therefore,for the partition function we getZ =N[D Φ][DA ][DB ]exp −S GF− d 4x TriF µνB µν4(3)Notice that the ﬁeld B µνtransforms covariantly under a gauge transformation of SU (N )B µν−→B Uµν=UB µνU †,from which it follows that the quadratic term Tr B µνB µνis left invariantTr B µνB µν=Tr B U µνB Uµν.Also,it is worth remarking that the ﬁeld B µνdoes not appear in the gauge ﬁxing term S GF (A,b,c,¯c ).According to ’t Hooft procedure,we can now pick up any component of B µν,say B 12,and,due to its hermiticity,diagonalize it by a suitable transformation Ωof SU (N ),namelyB 12→B diag12=ΩB 12Ω†.Due to the invariance of Tr B µνB µν,we haveTr B µνB µν=Tr2B 12B 12+B jk B jk=Tr2ΩB 12Ω†ΩB 12Ω†+ΩB jk Ω†ΩB jk Ω†=Tr2B diag 12B diag12+ΩB jk Ω†ΩB jk Ω†,(4)where the sum over the indices (j,k )does not in-clude the component B 12.The partition functionZ becomesZ =N[D Φ][DA ][DB ][D Ω]exp −S GF− d 4xi4Tr2ΩB 12Ω†ΩB 12Ω†+ΩB jk Ω†ΩB jk Ω†where we have inserted the integration measure [D Ω]over the gauge transformations which diag-onalize B 12.This is always possible,thanks to eq.(4).Performing now the change of variables B µν→Ω†B µνΩ,Ω→Ω,(5)3 we obtainZ=N [DΦ][DA][DB][DΩ]exp d4x Tr −iBµνBµν −S GF4The change of variables(5)has the eﬀect of mov-ing theΩ’s from the quadratic term BB to theﬁrst term F B.Recalling then that theΩ’s areprecisely those transformations which diagonalizeB12,it follows thatΩFµνΩ†=Ω ∂µAν−∂νAµ−[Aµ,Aν]+([∂µ,∂ν]Ω†)Ω Ω†,Fµν=[Dµ,Dν].Finally,we can path integrate theﬁeld B obtain-ing the expressionZ=N [DΦ][DA][DΩ]exp d4x T r −14M.N.Chernodub, F.V.Gubarev,M.I.Po-likarpov,V.I.Zakharov,Monopoles and Con-ﬁning Strings in QCD,hep-lat/0103033.8. F.Fucito,M.Martellini,M.Zeni,Nucl.Phys.B496(1997)259.9.K.-I.Kondo,Phys.Rev.D57(1998)7467.。

抗生素生长促进剂对罗非鱼肠道菌群的效用

Arch Microbiol (2010) 192:985–994DOI 10.1007/s00203-010-0627-z123ORIGINAL PAPERE V ects of the antibiotic growth promoters X avomycin and X orfenicol on the autochthonous intestinal microbiota of hybrid tilapia (Oreochromis niloticus $£O. aureus #)Suxu He · Zhigang Zhou · Yuchun Liu · Yanan Cao · Kun Meng · Pengjun Shi · Bin Yao · Einar RingøReceived: 29 March 2010 / Revised: 24 August 2010 / Accepted: 1 September 2010 / Published online: 16 September 2010© Springer-Verlag 2010Abstract The 16S rDNA PCR-DGGE and rpo B quantita-tive PCR (RQ-PCR) techniques were used to evaluate the e V ects of dietary X avomycin and X orfenicol on the autoch-thonous intestinal microbiota of hybrid tilapia. The W sh were fed four diets: control, dietary X avomycin, X orfenicol and their combination. After 8weeks of feeding, 6 W sh from each cage were randomly chosen for the analysis. The total number of intestinal bacteria was determined by RQ-PCR. The results showed that dietary antibiotics signi W -cantly in X uenced the intestinal microbiota and dramatically reduced the intensity of total intestinal bacterial counts. The intensity of some phylotypes (EU563257, EU563262 and EU563255) were reduced to non-detectable levels by both dietary antibiotics, while supplementation of X orfenicol to the diet also reduced the intensity of the phylotypes EU563242 and EU563262, uncultured Mycobacterium sp.-like, uncultured Cyanobacterium -like and uncultured Cyanobacterium (EU563246). Dietary X avomycin only reduced the OTU intensity of one phylotype, identi W ed as amember of the phylum Fusobacteria . The antibiotic combi-nation only reduced the phylotypes EU563242 and EU563262. Based on our results, we conclude that the reduced e V ect of X orfenicol on intestinal microbiota was stronger than that of X avomycin, and when X avomycin and X orfenicol were added in combination, the e V ect of X orfeni-col overshadowed that of X avomycin.Keywords Hybrid tilapia · Dietary X avomycin · Florfenicol · RQ-PCR · DGGE · Intestinal bacteriaIntroductionAquaculture animals are colonized by trillions of microor-ganisms that have a symbiotic relationship with their host and are distributed in gill, body surface and gastrointestinal (GI) tract (Frenkiel and Mouëza 1995; Armstrong et al.2001; Izvekova et al. 2007). The majority of these microbes inhabits the GI tract and plays an important role in nutri-tional, physiological and pathological events (Denev et al.2009; Merri W eld et al. 2010; Nayak 2010). During the last decade, several studies have showed that the composition of W sh intestinal microbiota is highly variable and is a V ected by the developmental stages, diet and environmen-tal conditions (González et al. 1999; Ringø and Birkbeck 1999; Spanggaard et al. 2000; Huber et al. 2004).In China, antibiotics as growth promoters are widely used in aquafeeds, especially X avomycin and X orfenicol.Flavomycin is a glycolipid antibiotic produced by Strepto-myces species and inhibits peptidoglycan polymerases through impairment of the transglycolase activities of peni-cillin-binding proteins (Butaye et al. 2003). Flavomycin is known to change the equilibrium of gut microbiota and is active primarily against Gram-positive bacteria but also toCommunicated by Shuang-Jiang Liu.S. He · Z. Zhou (&) · Y. Liu · Y. Cao · K. Meng · P. Shi · B. Yao (&)Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, 100081 Beijing, People’s Republic of China e-mail: zhou_zg@ B. Yaoe-mail: yaobin@E. RingøNorwegian College of Fishery Science,Faculty of Biosciences, Fisheries and Economics, University of Tromsø, 9037 Tromsø, Norway抗生素土生的丆土著的986Arch Microbiol (2010) 192:985–994123some extent against certain Gram-negative bacteria, such as Pasteurella and Brucella (Huber and Nesemann 1968).Bacteria species such as Clostridium perfringens and many other clostridia species, several species of Enterococcus ,including E. gallinarum , E. casseli X avus , E. faecium ,E.mundtii and E. hirae , are reported to be of natural resis-tance to X avomycin (Devriese 1980; Dutta and Devriese 1980, 1982; Butaye et al. 1998, 2000a , b , 2001). Another important antibiotic is X orfenicol—a broad-spectrum bacte-riostatic antibiotic binding the 50S ribosomal subunit of susceptible pathogens (Plumb 2004). This antibiotic is reported to be e V ective against important W sh pathogens such as Yersinia ruckeri , Flavobacterium psychrophilum and Aeromonas salmonicida (Fukui et al. 1987; Samuelsen et al. 1998; Bruun et al. 2000), and Pasteurella multocida ,Mannheimia haemolytica , Actinobacillus pleuropneumo-niae and Streptococcus suis in vitro (Priebe and Schwarz 2003). However, the in X uence of antibiotics on intestinal microbiota has been determined by traditional culture-based method (Samuelsen et al. 1998; Bruun et al. 2000;Butaye et al. 2001). A large percentage of the intestinal microbiota cannot be cultured, resulting in limited under-standing of the impact of antibiotics on the autochthonous intestinal microbiota. Consequently, the objective of the present study was to obtain better knowledge and under-standing of the intestinal bacterial community of hybrid tilapia (Oreochromis niloticus $£O. aureus #) reared in cages and how supplementation of dietary X orfenicol and X avomycin, either singly or in combination, impacts the autochthonous intestinal microbiota.Materials and methods Experimental dietsBasal diets containing 26.0% protein and 3.0% lipid (Table 1) were formulated according to Li (2001). In the present study, four di V erent diets were used: basal diet (CK), diet supplemented with 20mg X orfenicol kg ¡1, diet supplemented with 20mg X avomycin kg ¡1 and a diet sup-plemented with 10mg X orfenicol kg ¡1 and 10mg X avomy-cin kg ¡1.Feeding trialThe culture experiment was conducted in a 4,000-m 2earthen pond at a local aquaculture farm, Jiaxing, Zhejiang,China. Juvenile hybrid tilapia (Oreochromis niloticus $£O. aureus #) was acclimated in a X oating net cage (4.0m £2.0m £1.5m) for 2weeks. Water depth of the pond was approximately 1.5m. After 2days of starvation,uniform W sh (50.89§0.27g) were randomly distributedinto 12 X oating net cages (1.1m £1.1m £1.1m). Each dietary group was fed in triplicate cages, and each cage contained 20 W sh. The W sh were hand-fed 3% of initial body weight three times a day (08:00, 11:30 and 17:30), and the feed ration was adjusted weekly to insure tilapias in each cage consume the diet pellets within 1h. Each cage was individually aerated, and one tenth of the experimental pond water was exchanged by fully aerated tap water each week. During the feeding period, rearing temperature was 27.0§3.0°C, while dissolved oxygen (DO)>5.0mg oxy-gen l ¡1, pH 7.8, NH 4+-N <0.50mg nitrogen l ¡1 and NO 2-N <0.05mg nitrogen l ¡1. The photoperiod was W xed at a natural condition from 5:00 to 19:00.Sampling of the autochthonous gut microbiotaSix W sh from each cage were randomly collected after 8-week feeding for gut bacterial analysis. Sampling of the autochthonous microbiota from the whole intestine was carried out after two days of starvation as previously described (Zhou et al. 2007). Brie X y, the digestive tracts were aseptically removed in their entirety, slit open with a sterile scalpel, and the contents and non-adherent bacteria were rinsed three times in phosphate-bu V ered saline (PBS; 0.1M, pH 7.2). The surface of each intestine wasTable 1Ingredients and chemical compositions of the experimental diets (%)aBasal diet: Cotton seed meal, Shandong, P.R. China (CP 40.0%),15.0; Rapeseed meal, Henan, P.R. China (CP 38.0%), 23.0; Single cell protein, Zhejiang, P.R. China (CP 73.8%), 1.0; Intestine casing meal,Zhejiang, P.R. China (CP 55.6%), 1.0; Malt sprouts, Zhejiang, P.R.China (CP 26.3%), 6.0; Wheat middings, Zhejiang, P.R. China (CP 16.7%), 13.0; Wheat X our, Shandong, P.R. China (CP 12.7%), 10.0;DDGS, Shandong, P.R. China (CP 26.6%), 6.0; Corn, Shandong, P.R.China (CP 9.5%), 3.0; Bentonite, Zhejiang, P.R. China, 6.0; Rice bran,Jiangsu, P.R. China (CP 14.2%), 12.0; Betaine, Shandong, P.R. China,0.1; Phospholipid oil, Jiangsu, P.R. China, 1.4; Calcium phosphate,Jiangsu, P.R. China, 1.6; Vc phosphate, Beijing, P.R. China, 0.02;Choline chloride, Shandong, P.R. China, 0.1; Antioxidantr, Shanghai,P.R. China, 0.03; Antimouldr, Shanghai, P.R. China, 0.1bSupplied by Zhejiang Yiwu Huatai Feed Company cSee the reference (Zhou et al. 2007)Ingredients CKFlavomycin Florfenicol Combinationof antibioticsBasal diet a 99.499.499.499.4Florfenicolb 0.00.00.0020.001Flavomycinb0.00.0020.00.001Mineral/vitamin mix c 0.60.60.60.6Chemical composition Crude protein 26.026.026.026.0Crude lipid 3.0 3.0 3.0 3.0Moisture 9.49.610.29.9Ash7.47.87.37.6Arch Microbiol (2010) 192:985–994987123homogenized using a glass homogenizer as described else-where (LeaMaster et al. 1997) and stored in 2-ml Eppen-dorf tubes at ¡20°C until analysis (Zhou et al. 2009a ).DGGE analysisPooled gut samples from six W sh in each cage (»200mg)were used to avoid erroneous conclusions due to individual variation in gut microbiota as described by Ringø et al.(1995), Spanggaard et al. (2000) and He et al. (2009). The total genomic DNA from the pooled gut samples were extracted using cetyltrimethylammonium bromide (CTAB;Gri Y ths et al. 2000) and lysozyme methods (Miller et al.1999) with some modi W cations. Brie X y, the gut samples were mixed with 500 l 5mg ml ¡1 lysozyme solution.After incubation at 37°C for 2h, 50 l 10mg ml ¡1 protein-ase K (Sigma, St. Louis, MO, USA) was added and mixed gently, followed by incubation at 55°C for 20min. Then 500 l CTAB lysis bu V er (100mM Tris–HCl, 100mM Na-EDTA, 1.5M NaCl, 1% CTAB, 2% SDS, pH 8.0) was added and incubated at 65°C for 2h. The DNA was recov-ered by precipitation with isopropanol and puri W ed as described by Liu et al. (2008). The V3 region of the 16S rRNA gene was ampli W ed with primers 338f (5Ј-ACTC CTACGGGAGGCAGCAG-3Ј) with a 40 base GC clamp at the 5Ј end and 518r (5Ј-ATTACCGCGGCTGCTGG-3Ј).The 50- l PCR reaction system contained 1£PCR bu V er (20mM Tris–HCl (pH 8.4) and 50mM KCl), 200 M dNTP, 500 nM each primer, 1.75mM MgCl 2, 670ng l ¡1bovine serum albumin, 1.25 U Platinum ® Taq DNA poly-merase (Invitrogen, USA) and 2 l puri W ed DNA. The PCR conditions were as follows: 5min of initial denaturation at 94°C, followed by 28 cycles of 30s of denaturation at 94°C, 30-s annealing at 65°C (decreasing 1°C per cycle until 56°C), and 30-s extension at 72°C and a W nal exten-sion at 72°C for 10min. PCR products were examined by 2% agarose gel electrophoresis. DGGE was performed with a D-Code universal mutation system (Bio-Rad, Her-cules, CA, USA). PCR products (»800ng) were loaded onto polyacrylamide gels in 0.5£TAE bu V er, with a gra-dient of 40–60% denaturant. Electrophoresis was per-formed at 60°C, 65V for 16h. After electrophoresis, gels were stained for 20min in distilled water containing ethi-dium bromide (0.5 g ml ¡1) and visualized under UV light. DGGE bands were excised from the gels, resus-pended in 100 l distilled water and kept at 4°C overnight.The supernatant was used as the template for a second round of PCR under the same conditions. The PCR prod-ucts were ligated into pGEM-T Easy vector (Promega,Madison, WI, USA) for sequencing (Invitrogen, Shanghai,China). Representative sequences were deposited in the NCBI database under accession numbers EU563242–EU563265.Total intestinal bacteria analysisEnumeration of total bacteria was conducted by real-time PCR according to Takahashi et al. (2006) and Silkie and Nelson (2009) with some modi W cations. Brie X y, several cultured bacteria were selected based on the predominant microbiota present in DGGE with an abundance index greater than 5%. In this study, Clostridium thermocellum B108 (Gram-positive bacteria) and Sphingomona s sp. B222(Gram-negative bacteria) were chosen as standards. Both bacterial species were cultured overnight in Luria–Bertani (LB) medium, and the total number of bacteria was counted using a hemocytometer. Thereafter, each bacterial strain was mixed equally at 0.5£108 cells ml ¡1, and total geno-mic DNA was extracted from 1ml of the combined mixture using CTAB (Gri Y ths et al. 2000) and lysozyme methods (Miller et al. 1999). To increase the concentration of puri-W ed intestinal DNA, the genomic DNA was pre-cooled at ¡70°C for »2h, freeze-dried (CHRIST, Osterode, Ger-many) overnight and solved in TE bu V er to the ideal con-centration of 50ng l ¡1.Serial dilutions of standards at 103, 104, 105 and 106CFU per template reaction were prepared for calibration.The RNA polymerase -subunit gene (rpo B; one copy in bacteria) was ampli W ed using the primers rpo B1698f (5Ј-A ACATCGGTTTGATCAAC-3Ј) and rpo B2041r (5Ј-CGT TGCATGTTGGTACCCAT-3Ј; Dahllöf et al. 2000). The reaction mixture (20 l) was prepared according to the manufacturer’s protocol: 7 l PCR-grade water, 1 l each primer (5 mol l ¡1), 10 l 2£real-time PCR master mix (SYBR Green; TOYOBO, Shanghai, China) and 1 l DNA template (50ng l ¡1). The PCR conditions consisted of ini-tial denaturation at 95°C for 5min, 40 cycles of denatur-ation at 95°C for 30s, annealing at 55°C for 30s and extension at 72°C for 30s, with a W nal extension step at 72°C for 5min.The concentration of each standard (CFU ml ¡1) was inputted into the LightCycler 2.0 software using the thresh-old cycle value (C T ) to construct a standard for absolute quanti W cation analysis. The number of bacteria present in unknown samples (12 samples) was calculated based on the standard curve. Each sample was analyzed in at least four replicates.Statistical analysisThe gel images were analyzed using the public domain NIH Image program to calculate relative abundance (RA, %;Simpson et al. 1999). Cluster analysis was performed based on the unweighted pair group method using the arithmetic mean algorithm (UPGMA) by the program NTSYS. In this study, pairwise similarity coe Y cient (C s) less than 0.60 is regarded as signi W cant di V erence; while 0.60·C s <0.85is988Arch Microbiol (2010) 192:985–994123marginal di V erence, and C s ¸0.85 is very similar accord-ing to Sun et al. (2004). The Shannon index of bacterial diversity, H , was calculated as Shannon and Weaver (1963)described.Results are presented as mean §SD. Data were subjected to one-way ANOVA to test the e V ect of dietary treatment. When signi W cant di V erences were detected (P <0.05), Duncan’s multiple range test was used to com-pare mean values among dietary treatments. All statistical analysis was carried out using the statistic software SPSS version 10.0.ResultsDGGE pro W les of intestinal microbiota in tilapiaBacterial DGGE pro W les of four di V erent treatments showed signi W cant di V erences (Fig.1, Tables 2, 4), and thedi V erence of the interior-group was more signi W cant than that of inter-group. There were 18.67§0.47, 15.00§0.82,14.33§0.47 and 14.66§0.47 OTUs in CK, X avomycin,X orfenicol and antibiotic combination groups, respectively (Table 2). The pairwise similarity coe Y cients (C s) matrix for the intestinal bacterial community of hybrid tilapia based on the DGGE W ngerprints is shown in Table 3. The bacterial community in X avomycin group was similar to that of CK with a C s value of 0.84. The bacterial commu-nity of CK was marginally di V erent to that of X orfenicol and the combination of X avomycin and X orfenicol.Identi W cation of dominant DGGE bandsA total of 19 representative OTUs were retrieved from the bacterial DGGE pro W les (Table 4). Proteobacteria (2 OTUs),Actinobacteria (2 OTUs), Cyanobacteria (3 OTUs), Fuso-bacterium (1 OTU) and Firmicutes (1 OTU) were the predominant autochthonous bacteria in hybrid tilapia intestine. The relative abundance (RA) results showed that OTU 3 (uncultured bacterium, EU418508), 7 (uncultured bacterium, EF532770), 8 (uncultured Cyanobacterium ,EF630240), 10 (uncultured prokaryote, AJ867878), 11(uncultured bacterium clone, DQ675149), 13 (Sphingo-monas sp., EU442226) and 18 (uncultured -Proteobacte-rium , EF697165) were not a V ected by dietary antibiotics. In contrast to these results, the intensities of OTU 4 (uncul-tured bacterium, AB206034), 12 (Streptomyces sp.,EU159565) and 19 (uncultured prokaryote, AJ867878) were reduced to non-detectable levels by dietary X avomycin and X orfenicol. One interesting observation was that OTU 17,an uncultured bacterium with 100% similarity to accession no. EF599665, was reduced to non-detectable levels by dietary X orfenicol and the antibiotic combination, but no di V erence in RA was observed between the control group (CK) and W sh that received X avomycin. Compared with CK, supplementation of dietary X orfenicol decreased the intensities of OTU 1 (uncultured bacterium, AJ504589), 2(uncultured Cyanobacterium , DQ158167), 5 (uncultured Cyanobacterium, EU751409) and 14 (uncultured Mycobac-terium sp., EF438322), but the intensities of OTU 9 (uncul-tured bacterium, EF669487) and 16 (uncultured bacterium,Fig.1DGGE pro W le generated from the V3-16S rDNA fragments of the bacteria from the intestinal wall of hybrid tilapia O. niloticus $£O. aureus #. CK1–3 represent samples taken from the intestine of tilapia fed control diet without antibiotic supplement; Fm1–3 are sam-ples from the intestine of tilapia fed diet supplemented with X avomy-cin; Fn1–3 are samples from the intestine of tilapia fed diet supplemented with X orfenicol; and FF1–3 are samples from the intes-tine of tilapia fed diet supplemented with X avomycin and X orfenicolTable 2E V ect of di V erent feeding regimes on the intestinal microbiota of hybrid tilapia O. niloticus $£O. aureus #Data (mean §SD) in the same row sharing a common superscript are not signi W cantly di V erent (Duncan’s multiple range test, P >0.05)FeedingCKFlavomycin Florfenicol Combination of antibiotics P value Bacterial counts(£107 CFU g ¡1 dry matter) 1.11§0.10a 0.47§0.05b 0.2§0.01c 0.43§0.08b <0.001OTUs 18.67§0.47a 15.00§0.82b 14.33§0.47b 14.66§0.47b <0.001H 2.64§0.02a 2.45§0.02b 2.36§0.01c 2.48§0.02b <0.001E H0.73§0.01a0.73§0.02a0.70§0.01a0.79§0.02b0.002Arch Microbiol (2010) 192:985–994989123AJ548786) were elevated. An interesting W nding was that the intensity of OTU 15 on the DGGE, identi W ed as a mem-ber of the phylum Fusobacteria , was reduced only by die-tary X avomycin. The combination of the two antibiotics signi W cantly decreased OTU 1 as a RA value of 1.37§0.12 was observed in the combined antibiotics group compared to the RA value of 2.60§0.24 in CK.Total intestinal bacterial countsThe total intestinal bacterial counts analyzed by RQ-PCR varied from 0.20§0.01 to 1.11§0.10CFU £107 g ¡1 as shown in Table 2. Supplementation of dietary X orfenicol and X avomycin signi W cantly reduced (P <0.05) the intesti-nal bacteria. Shannon diversity indexes (H )of the antibiot-ics treatments were signi W cantly lower (P <0.05) than that of CK. The value of H for X orfenicol group was higher than that of X avomycin and antibiotic combination (P <0.05),but the Shannon equitability indexes (E H ) were not a V ected by dietary antibiotics compared to CK (P >0.05).DiscussionIn the present study, the autochthonous intestinal microbi-ota was signi W cantly modulated by X avomycin. This result is consistent with previous reports that X avomycin reduced the incidence of the animal pathogens Salmonella and Clostridium in pre-slaughter broilers (Bolder et al. 1999)and modulated the ruminal gut microbiota (Edwards et al.2005). In the study of broiler chicks, Gunal et al. (2006)demonstrated that the counts of total bacteria and Gram-negative bacteria were signi W cantly decreased by X avomy-cin after 21 and 42days of feeding. Zhou et al. (2009b )observed that dietary X avomycin a V ected the autochtho-nous intestinal bacterial community in tilapia. In the present study, several intestinal phylotypes such as Streptomyces sp.-like bacterium, uncultured bacterium (EU563262),uncultured prokaryote-like bacterium and Fusobacteria bacterium (EU563264) were reduced by X avomycin. Fuso-bacterium species are Gram-negative bacteria (Garcia et al.1992) and have been reported in bovine rumen, pig, poultry and W sh (GU301238; Tan et al. 1996; Anderson et al. 2000;Edwards et al. 2005). F. necrophorum is generally regarded as an opportunistic pathogen (Brazier et al. 2002) but hasbeen reported to be inhibited by X avomycin in a study of sheep (Edwards et al. 2005). More recently, Jeong et al.(2009) showed that Fusobacterium spp. in human gut were susceptible to X avomycin. Previous studies reported that Fusobacterium spp. have a very high rate of deamination by converting excessive dietary amino acids to ammonia (Russell et al. 1991; Attwood et al. 1998), and suppression of Fusobacterium by X avomycin has been reported to have a favorable e V ect on nitrogen metabolism (Edwards et al.2005).The present study showed that supplementation of dietary X orfenicol reduced a number of autochthonous intestinal bacteria in tilapia compared to X avomycin. For example, the intensity of Streptomyces sp.-like bacterium,uncultured bacteria (EU563262 and EU563265) and uncul-tured prokaryote-like bacterium were reduced to non-detectable levels by dietary X orfenicol. On the other hand,some gut bacteria including uncultured Mycobacterium sp.-like bacterium, uncultured Cyanobacterium -like bacte-rium, uncultured Cyanobacterium (EU563246) and uncultured bacterium (EU563242) were partly decreased. Mycobacte-ria are obligate aerobic, acid-fast, Gram-positive, non-spore forming, non-motile and prevalent in soil and water (Frerichs 1993). In two recent studies (He et al. 2009; Zhou et al. 2009a ) using DGGE, Mycobacterium sp.-like bacteria were detected in the tilapia intestine. In the present study,X orfenicol a V ected the RA value of Mycobacterium sp.-like bacteria from 1.40§0.16 to 0.93§0.21; however, dietary X avomycin had no e V ect.Three species of Cyanobacteria were detected in the tila-pia intestine (Table 4). Cyanobacteria possess the capabil-ity to store abundant nutrients, and some species can convert gaseous nitrogen to ammonia via nitrogen W xation (Stewart 1967). Cyanobacteria are well known for their ability to produce a large number of diverse secondary metabolites (Vining 1992), which cause mortality, initiate or promote tumors or deteriorate the health of several culti-vated species (nile tilapia, cat W sh, white shrimp and rain-bow trout; Smith et al. 2008). Previous investigations have reported Cyanobacteria in the intestine of W lter-feeding W sh such as Atlantic menhaden (Brevoortia tyrannus ), silver carp (Hypophthalmichtyhs molitrix ) or tilapia (Oreochr-omis niloticus $£O. aureus #; Friedland et al. 2005;Kolmakov et al. 2006; He et al. 2009). In the present study,two species of Cyanobacteria were reduced by X orfenicol.Table 3Pairwise similarity coe Y cients (C s) matrix for the intestinal microbiota of hybrid tilapia O. niloticus $£O. aureus #CKFlavomycin FlorfenicolCombination of antibioticsCK 1.00Flavomycin 0.84MS 1.00Florfenicol0.79MS 0.95NS 1.00Combination of antibiotics0.79MS0.95NS1.00NS1.00NS very similar, MS marginal di V erence990Arch Microbiol (2010) 192:985–994123T a b l e 4R e p r e s e n t a t i v e s o f O T U s o r c l o n e s i s o l a t e d f r o m t h e i n t e s t i n e o f h y b r i d t i l a p i a u n d e r t h e e x p e r i m e n t a l f e e d i n g r e g i m e s a n d t h e i r r e l a t i v e a b u n d a n c eP h y l o g e n e t i c g r o u pB a n dA c c e s s i o n n o .R e l a t i v e a b u n d a n c e (R A , %)P v a l u e C l o s e s t r e l a t i v e (o b t a i n e d f r o m B L A S T s e a r c h )I d e n t i t y (%)I s o l a t e d f r o mC KF l a v o m y c i n F l o r f e n i c o l C o m b i n a t i o n o f a n t i b i o t i c s P r o t e o b a c t e r i a 13E U 5632632.77§0.653.07§0.344.00§0.433.73§0.820.213S p h i n g o m o n a s s p . (E U 442226)100D e e p t e r r e s t r i a l s u b s u r f a c e (B r o w n , u n p u b l i s h e d d a t a , N C B I )18E U 56326010.13§1.067.90§0.2910.43§1.349.27§0.420.082U n c u l t u r e d -p r o t e o b a c t e r i u m (E F 697165)99H u m a n g a s t r o i n t e s t i n a l r e s e c t i o n s p e c i m e n (F r a n k e t a l . 2007)A c t i n o b a c t e r i a 11E U 5632561.70§0.162.03§0.382.07§0.171.87§0.250.492U n c u l t u r e d a c t i n o b a c t e r i u m (D Q 675149)99L i m n o l o g y o f S t r a t i W e d L a k e s (A l l g a i e r a n d G r o s s a r t , u n p u b l i s h e d d a t a , N C B I )12E U 5632571.20§0.24a –b –b –b<0.001S t r e p t o m y c e s s p . 926 (E U 159565)96A c i d i c s o i l i n Y u n n a n , C h i n a (X u e t a l . u n p u b l i s h e d d a t a , N CB I )14E U 5632581.40§0.16a 1.57§0.21a 0.93§0.21b 1.53§0.21a0.04U n c u l t u r e d M y c o b a c t e r i u m s p . (E F 438322)98C o a l t a r c o n t a m i n a t e d s e d i m e n t (D e B r u y n e t a l . 2007)C y a n o b a c t e r i a 2E U 5632433.13§0.29a 3.73§0.49a 1.87§0.25b 3.40§0.45a<0.001U n c u l t u r e d c y a n o b a c t e r i u m (D Q 158167)98F r e s h w a t e r l a k e , G e r m a n y (C o r r e d o r e t a l . u n p u b l i s h e d d a t a , N C B I )5E U 5632460.93§0.05a 1.43§0.17a 0.57§0.05b 1.13§0.26a0.004U n c u l t u r e d c y a n o b a c t e r i u m (E U 751409)100S a n d s t o n e f o r m a t i o n s (K u r t z e t a l . u n p u b l i s h e d d a t a , N C B I )8E U 56325110.23§0.429.13§1.2711.77§1.2010.10§1.530.243U n c u l t u r e d c y a n o b a c t e r i u m (E F 630240)97S e a w a t e r (M o h a m e d e t a l . 2008)F u s o b a c t e r i u m 15E U 5632643.50§0.75a 1.97§0.39b 2.50§0.22a b 3.37§0.46a0.042F u s o b a c t e r i a b a c t e r i u m (D Q 837051)100H u m a n f e c e s (F i n e g o l d e t a l . 2003)F i r m i c u t e s 6E U 5632488.80§0.94b 11.63§1.05a 6.43§0.61c 9.30§0.51b0.002U n c u l t u r e d C l o s t r i d i u m s p . (D Q 168144)100E v e r g l a d e s w e t l a n d s (U z a n d O g r a m 2006)U n c l a s s i W e d b a c t e r i a1E U 5632422.60§0.24a 2.50§0.16a 1.60§0.14b1.37§0.12b <0.001U n c u l t u r e d b a c t e r i u m (A J 504589)99A c t i v a t e d s l u d g e (B r o w n a n d T u r n e r , u n p u b l i s h e d d a t a , N C B I )3E U 5632451.00§0.161.20§0.291.23§0.171.13§0.210.717U n c u l t u r e d b a c t e r i u m (E U 418508)100I n t e s t i n a l m i c r o X o r a o f C t e n o p h a r y n g o d o n i d e l l u s (H u a n g e t a l . u n p u b l i s h e d d a t a , N C B I )4E U 5632620.27§0.05a –b–b –b <0.001U n c u l t u r e d b a c t e r i u m (A B 206034)94A c t i v a t e d s l u d g e (O s a k a e t a l . 2006)。

学术英语_社科Unit5五单元原文及翻译

UNIT 5 Sociology Matters1.Culture is the totality of learned,socially transmitted customs,knowledge,material objects,and behavior.It includes the ideas,values,customs,and artifacts of groups of people.Though culture differ in their customs,artifacts,and languages,they all share certain basic characteristics.Furthermore,cultural characteristics change as cultures develop ,and cultures infuence one another through their technological ,commercial, and artistic achievements.文化是指社会传播学，海关，知识，材料的对象，和行为。

它包括思想，价值观，习俗，和人群的文物。

尽管文化在他们的习俗，文物，和语言不同，但是他们都有一些共同的基本特性。

此外，当文化发展时文化特征也在变化，并且文化通过他们的技术，商业，艺术成就相互影响。

Cultural universals文化共性2.All societies,despite their differences,have developed certain general practices known as cultural universals.Many cultural universals are ,in fact,adaptations to meet essential human needs ,such as people’s need for food ,shelter,and clothing. Anthropologist George murdock compiled a list of cultural that included athletic sports, cooking ,funeral ceremonies,medicine,and sexual restrictions.所有的社会，尽管他们的差别，已经形成了一定的一般做法被称为文化的共性。

人教版英语的高二下册教学设计五篇

人教版英语的高二下册教学设计五篇布鲁纳说过:“学习最好的刺激是对所学教材的兴趣”，对学生来说“兴趣”将直接影响学习效果。

下面是小编整理的人教版英语高二下册的教学设计5篇，欢迎大家阅读分享借鉴，希望大家喜欢，也希望对大家有所帮助。

人教版英语高二下册的教学设计1教学准备教学目标1、知识目标(1).理解并记住Reading部分本单元的单词和短语。

(2).理解并掌握整个故事的情节,并能填写summary.2、能力目标(1)充分发挥学生的主体地位，调动学生思维的积极性，提高综合语言的运用能力(2)通过对学生说读写的训练，增大学生的语言输入，增强其语言输出能力。

3、情感、态度、价值观目标学生分析布莱船长在40多天的航程中所采用的航海技术以及所表现出的领导才能。

同时，又适时地对他们进行情感教育：在任何困难面前绝不畏惧，不抛弃，不放弃。

教学重难点教学重点与难点：读写说均为本节课的重点，写和说部分应为难点，需加大指导和练习。

教学过程Teaching procedures:Lead-in：通过歌曲Sailing导入，让学生在轻松愉悦的音乐下近入新课的学习之中。

促使学生积极主动地进入学习状态。

ComprehensionStep I Please Skim the passage and get the main idea.Step II. Scan the passage: True or False.1. I was forced to join Captain Bligh in the small boat.2. After the c rew took over the ship “Bounty”, Captain Bligh was allowed to take with him a chart , a compass and a quadrant.3. It was very difficult for us to get a correct reading from the quadrant as the boat moved constantly during the course.4. Captain Bligh used a system called “dead reckoning” and he knew there was land directly southwest of their original position.5. Captain Bligh was as weak as the rest of us but he was determined not to give up.6. Captain Bligh kept us busy and tried to take our minds off our stomachs and thirst all the way.7. We finally escaped the jaws of death and arrived in Timor over fifty days after being set loose in our small boat.Step III. Group work: further reading.When captain Blight returned home he was honored as a hero. Discuss in groups whether he should receive a special medal or not.Step IV. Affective educationAfter learning the text, as senior three students, what can we learn from Captain Blight in our life?Step V. Summary：I am _____ to have sailed with Captain Bligh on his journey of over40 days through about4,000 miles in an open boat ______the Pacific Ocean in 1789.In the beginning, on our ________(depart), some of the crew took _____theship and the captain ___________(deposit) into a smallboat. Thus we werecaught _____a dilemma. We decided to stick with him _______thick and thin though we seemed to face _____uncertaindeath.During the long and toughjourney, we encountered many unexpected hardships. Despite _____(lack) of foodand water, he kept us _______(occupy) and cheerful to take our minds ____troubles. All the way he taught us how to cope _______various situations. Finallythey arrived at Timor __________(success) andthey were honored as _______(hero).The story shows that one man’sspirit and his determinatio n should not ________ (defeat) by circumstances.Complexsentences(分析并翻译1-2个长难句)Challengeyourself!---Grammar Filling1. I’m proud to have sailed withCaptain Blight ____his journey of over 40 days _________about 4,000miles ____anopen small boat _______ the Pacific Ocean.2. On our _________(depart) from T ahiti, some crew took _____the ship. And those of us onboard ____________(catch) in a dilemma.3. As you can see from the map we kept_____a straight course pretty well.4. The captain kept us busy________ (read) the tables to work out our position .5. It was the extreme lack of waterthat was hard to cope with ______________ (psychology)6.He kept us busy and tried to take our minds课后习题Challenge yourself!---Grammar Filling1. I’m proud to have sailed with Captain Blight ____his journey of over 40 days _________about 4,000miles ____an opensmall boat _______ the Pacific Ocean.2. On our _________(depart) from T ahiti, some crew took _____the ship. And those of us on board ____________(catch) in a dilemma.3. As you can see from the map we kept _____a straight course pretty well.4. The captain kept us busy________ (read) the tables to work out our position .5. It was the extreme lack of water that was hard to cope with ______________ (psychology)6.He kept us busy and tried to take our minds _____our __________(stomach).人教版英语高二下册的教学设计2核心单词1. alternativen.可供选择的事物;(两者或以上)可能的选择adj. 供选择的, 二选一的常用结构：have no alternative but to do sth.只能做某事;除¡¡外别无选择We have no alternative but to go on.除了继续下去,我们别无选择。

tpo54三篇阅读原文译文题目答案译文背景知识

托福阅读tpo54全套解析阅读-1 (2)原文 (2)译文 (4)题目 (5)答案 (9)背景知识 (10)阅读-2 (10)原文 (10)译文 (12)题目 (13)答案 (18)背景知识 (20)阅读-3 (25)原文 (26)译文 (27)题目 (28)答案 (33)背景知识 (35)阅读-1原文The Commercialization of Lumber①In nineteenth-century America, practically everything that was built involved wood.Pine was especially attractive for building purposes.It is durable and strong, yet soft enough to be easily worked with even the simplest of hand tools.It also floats nicely on water, which allowed it to be transported to distant markets across the nation.The central and northern reaches of the Great Lakes states—Michigan, Wisconsin, and Minnesota—all contained extensive pine forests as well as many large rivers for floating logs into the Great Lakes, from where they were transported nationwide.②By 1860, the settlement of the American West along with timber shortages in the East converged with ever-widening impact on the pine forests of the Great Lakes states. Over the next 30 years, lumbering became a full-fledged enterprise in Michigan, Wisconsin, and Minnesota. Newly formed lumbering corporations bought up huge tracts of pineland and set about systematically cutting the trees. Both the colonists and the later industrialists saw timber as a commodity, but the latter group adopted a far more thorough and calculating approach to removing trees. In this sense, what happened between 1860 and 1890 represented a significant break with the past. No longer were farmers in search of extra income the main source for shingles, firewood, and other wood products. By the 1870s, farmers and city dwellers alike purchased forest products from large manufacturingcompanies located in the Great Lakes states rather than chopping wood themselves or buying it locally.③The commercialization of lumbering was in part the product of technological change. The early, thick saw blades tended to waste a large quantity of wood, with perhaps as much as a third of the log left behind on the floor as sawdust or scrap. In the 1870s, however, the British-invented band saw, with its thinner blade, became standard issue in the Great Lakes states' lumber factories.Meanwhile, the rise of steam-powered mills streamlined production by allowing for the more efficient, centralized, and continuous cutting of lumber. Steam helped to automate a variety of tasks, from cutting to the carrying away of waste. Mills also employed steam to heat log ponds, preventing them from freezing and making possible year-round lumber production.④For industrial lumbering to succeed, a way had to be found to neutralize the effects of the seasons on production. Traditionally, cutting took place in the winter, when snow and ice made it easier to drag logs on sleds or sleighs to the banks of streams. Once the streams and lakes thawed, workers rafted the logs to mills, where they were cut into lumber in the summer. If nature did not cooperate—if the winter proved dry and warm, if the spring thaw was delayed—production would suffer. To counter the effects of climate on lumber production, loggers experimented with a variety of techniques for transporting trees out of the woods. In the 1870s, loggers in the Great Lakes states began sprinkling water on sleigh roads, giving them an artificial ice coating to facilitate travel. The ice reduced the friction and allowed workers to move larger and heavier loads.⑤But all the sprinkling in the world would not save a logger from the threat of a warm winter. Without snow the sleigh roads turned to mud. In the 1870s, a set of snowless winters left lumber companies to ponder ways of liberating themselves from the seasons. Railroads were one possibility.At first, the remoteness of the pine forests discouraged common carriers from laying track.But increasing lumber prices in the late 1870s combined with periodic warm, dry winters compelled loggers to turn to iron rails. By 1887, 89 logging railroads crisscrossed Michigan, transforming logging from a winter activity into a year-round one.⑥Once the logs arrived at a river, the trip downstream to a mill could be a long and tortuous one.Logjams (buildups of logs that prevent logs from moving downstream) were common—at times stretching for 10 miles—and became even more frequent as pressure on the northern Midwest pinelands increased in the 1860s. To help keep the logs moving efficiently, barriers called booms (essentially a chain of floating logs) were constructed to control the direction of the timber. By the 1870s, lumber companies existed in all the major logging areas of the northern Midwest.译文木材的商业化①在19世纪的美国，几乎所有建筑材料都含有木材。

高英二第四课

⾼英⼆第四课Lesson 4 Love Is a Fallacy by Max Shulmas Teaching PointsⅠ. Background Knowledge Ⅱ. Introduction to the Passage Ⅲ. Text analysisⅣ. Rhetorical DevicesⅤ. QuestionsTeaching ProcessWarming upQuestion 1:What is love?Question 2: What is logic?Question 3: Love is blind?Question 4: Love is reason?Introduction to the Passage1. Type of literature: a piece of narrative writing--protagonist/antagonists--climax--denouement2. The main theme3. Well chosen title and words4. Style--a very fast pace with a racy dialogue full of American colloquialism and slang--employing a variety of writing techniques to make the story vivid, dramatic and colorfulText AnalysisVocabulary1. Pay attention to words and expressions in the following aspects respectively:Spelling and PronunciationSynonymsOppositesSimilar words and expressionsSettled or habitual usage2. Word building knowledgeEffective Writing Skills1. Employing colorful lexical spectrum, from the ultra learned terms to the infra clipped vulgar forms2. Too much figurative language and ungrammatical inversion for specific purposes3. The using of short sentences, elliptical sentences and dashes to maintain the speed of narration Rhetorical Devices1. metaphor2. antithesis3. transferred epithet4. hyperbole5. metonymy6. litotes7. ellipsis8. synecdoche9. inversion10. simile11. mixed metaphor12. rhetorical questionsSpecial DifficultiesAnalyzing the logical fallaciesUsing inverted sentences to achieve emphasisEffectively using many figures of speechUnderstanding colloquial expressions and slangAllusions:--Frankenstein--PygmalionParaphrasing some sentencesIdentifying figures of speechQuestions1. Define and give an example of each of the logical fallacies discussed in this essay.2. Can you find any evidence to support the view that the writer is satirizing a bright but self-satisfied young man?3. Comment on the language used by Polly. What effect does her language create?4. Why does the writer refer to Pygmalion and Frankenstein? Are these allusions aptly chosen?5. In what sense is the conclusion ironic?Assignment:Write a composition of classification.Lesson 4 Love Is a Fallacyby Max ShulmanⅠ. Additional Information Related to the Text:1. Max SchulmanMax Schulman (1919-1988) was a 20th century American writer humorist best known for his television and short story character Dobie Gillis, as well as for best-selling novels.He first delved into the world of writing as a journalist student at the University of Minnesota. Max Schulman?s earliest published writing was for Ski-U-Mah, the college humor magazine of the University of Minnesota, in the 1930s. His writing often focused on young people, particularly in a collegiate setting. He wrote his first novel, Barefoot Boy with Cheek《⽆礼的⾚脚少年》a satire on college life, while still a student. Schulman?s works include the novels Rally Round the Flag, Boys!,《孩⼦们，团结在旗帜的周围吧》which was made into a film starring Paul Newman and Joanne Woodward; The Feather Merchant《⾐冠楚楚的商⼈》，The Zebra Derby, Sleep till Noon, and Potatoes Are Cheaper. He was also a co-writer, with Robert Paul Smith, of the long-running Broadway play, The Tender Trap, which was later adapted into a movie starring Frank Sinatra and Debbie Reynolds.Schulman?s college charater, Dobie Gillis, was the subject of a series of short stories complied under the title The Many Loves of Dobie Gillis, which became the basis for the 1953 movie The Affairs of Dobie Gillis. Shulman also wrote the series? theme song. The same year the series began. Schulman published a Dobie Gillis novel, I was a Teenage Dwarf (1959). After his success with Dobie Gillis, Shulman syndicated a humor column, “On Campus”, to over 350 collegiate newspapers at one point.A later novel, Anyone Got A Match? satirized both the television and tobacco industries, as well as the Soth and college football. His last major project was House Calls, which began as a 1978 movie based on one of his stories; it spun off the 1979-1982 television series of the same name. Schulman was the head writer.Also a screenwriter, Schulman was one of the collaborators on a 1954 non-fiction television program, Light’s Diamond Jubilee, timed to the 75th anniversary of the invention of the lihght bulb.2. Logical fallacy:逻辑谬误An argument in logic presents evidence in support of some thesis or conclusion.（逻辑论证，即提⽀持某些论题或结论的论据。

矿物质缺乏引发的疾病

Pedosphere24(1):13–38,2014ISSN1002-0160/CN32-1315/Pc 2014Soil Science Society of China Published by Elsevier B.V.and SciencePressSources and Deﬁciency Diseases of Mineral Nutrients inHuman Health and Nutrition:A ReviewU.C.GUPTA1,∗1and S.C.GUPTA21Agriculture and Agri-Canada Canada,Crops and Livestock Research Centre,Charlottetown,PE C1A4N6(Canada)2The Department of Plastic Surgery,Loma Linda University,Loma Linda,CA92354(USA)(Received August30,2013;revised December8,2013)ABSTRACTMineral nutrients are fundamentally metals and other inorganic compounds.The life cycle of these mineral nutrients begins in soil,their primary source.Soil provides minerals to plants and through the plants the minerals go to animals and humans;animal products are also the source of mineral nutrients for humans.Plant foods contain almost all of the mineral nutrients established as essential for human nutrition.They provide much of our skeletal structure,e.g.,bones and teeth.They are critical to countless body processes by serving as essential co-factors for a number of enzymes.Humans can not utilize most foods without critical minerals and enzymes responsible for digestion and absorption.Though mineral nutrients are essential nutrients,the body requires them in small,precise amounts.We require them in the form found in crops and they can be classiﬁed into three diﬀerent categories:major, secondary,and micro or trace minerals.This classiﬁcation is based upon their requirement rather than on their relative importance. Major minerals such as potassium(K)and phosphorus(P)are required in amounts of up to10g d−1.The daily requirement of secondary and micro minerals ranges from400to1500mg d−1and45μg d−1to11mg d−1,respectively.To protect humans from mineral nutrient deﬁciencies,the key is to consume a variety of foods in modest quantities,such as diﬀerent whole grains,low fat dairy,and diﬀerent meats,vegetables and fruits.For insurance purposes,a supplement containing various mineral nutrients can be taken daily.Key Words:deﬁciency diseases,deﬁciency symptoms,origin,recommended daily dose,toxicityCitation:Gupta,U.C.and Gupta,S.C.2014.Sources and deﬁciency diseases of mineral nutrients in human health and nutrition: A review.Pedosphere.24(1):13–38.INTRODUCTIONLike water,carbohydrates,proteins,fats,vitamins and the enzymes required to digest them,mineral nu-trients are also essential to life.Minerals are inorganic substances,present in all body tissues andﬂuids and their presence is necessary for the maintenance of cer-tain physicochemical processes which are essential to life(Soetan et al.,2010).Over99%of the adult body’s 1000–1200g calcium(Ca)is in the bones and teeth, yet the remainder,less than1%,plays an essential part in the functioning of many diverse vital activities,such as maintenance and functioning of cell membranes and activation of enzymes and hormone secretion(Wise-man,2002).Humans require a number of mineral nu-trients known to play key role in maintaining human health.This investigation will include mineral nutri-ents which have been shown to be essential and of ut-most importance to human health.Silica(Si),tin(Sn) and cobalt(Co)are excluded from discussion as these are in plentiful supply in nature and their deﬁciency is seldom encountered.Furthermore,the understanding of their roles is less exact.Carbon(C),oxygen(O)and hydrogen(H)are primarily derived from air and water and are not discussed;nitrogen(N),a major mineral, has also been excluded as it is a component of proteins and that is not a part of the objective of this study.Mineral nutrients are the key to the engines we know of as vitamins.No vitamin can be absorbed or can carry out its intended function without the spe-ciﬁc minerals in very particular amounts.Minerals are fundamentally metals and other inorganic compounds that provide much of our skeletal structure,e.g.,bones and teeth.In addition,they are critical to countless body processes(Wikipedia Foundation Inc.,2002).Mineral nutrients can be separated into major,se-condary and micro or trace minerals.This classiﬁca-tion is based on their requirement by humans rather than their relative importance.The mineral nutrients included in this study are categorized as follows.Ma-jor:P and K;secondary:calcium(Ca),magnesium (Mg)and sulfur(S);and micro,trace or rare:boron∗1Corresponding author.E-mail:umesh.gupta@agr.gc.ca.14U.C.GUPTA AND S.C.GUPTA(B),chlorine(Cl),chromium(Cr),ﬂuoride(Fl),iodine (I),iron(Fe),manganese(Mn),molybdenum(Mo), nickel(Ni),selenium(Se),sodium(Na),vanadium(V) and zinc(Zn).With ongoing and future research,this list is expected to grow longer.The objective of this review was to report up-to-date information on mineral nutrients,their origin and natural occurrence,sources,daily requirement,func-tions,symptoms associated with their deﬁciency dis-eases,and their role in human nutrition.NATURAL OCCURRENCE OF MINERALSPlant foods contain almost the entire nutrient mi-nerals and organic nutrients established as essential for human nutrition.Every form of living matter re-quires these inorganic elements or mineral nutrients for their normal life processes(Soetan,2010).Mine-rals are inorganic(non-carbon)containing nutrients and are either positively charged(cation)or nega-tively charged(anion).Mineral nutrients are elements remaining after foods are burned completely to ash (Greene,2000).The primary and the only source of mi-neral nutrients found in plants,animals and humans is soil.The kinds of nutrients found vary depending upon the origin of the soil.For example,B occurs in high concentrations in sedimentary rocks and in clay-rich marine sediment due to the relatively high concentra-tion of B in seawater(Samir et al.,2011).Deposits of B are found in association with volcanic activity and where marshes or lakes have evaporated under arid conditions(Samir et al.,2011).The abundance and diversity of nutrient minerals are controlled directly by their chemistry,in turn de-pendent upon elemental abundance in the earth.The majority of minerals are derived from the earth’s crust (Stipanuk and Caudill,2012).Eight elements in order of decreasing abundance are:O,Si,aluminum(Al),Fe, Mg,Ca,Na and K,which comprise98%of the earth’s crust by weight(Stipanuk and Caudill,2012).Inor-ganic minerals include matter other than plant or ani-mal and do not include C,H and O as in living things.RELATIONSHIP OF MINERAL NUTRIENTS TO HUMAN NUTRITIONMineral nutrients are absolutely essential for good health.Scientists have established that at least28mi-neral elements are indispensable for normal nutrition (Health Lifestyles Inc.,1993).Furthermore,they are even more important than cking vitamins, the body can make some use of minerals,but lacking minerals,vitamins are useless(Health Lifestyles Inc., 1993).The shocking fact is that even if one prides themselves on eating a well-balanced diet,they are probably among the95%of Americans who are lac-king in at least one major mineral nutrient.The root of this problem lies in a mineral-poor earth.As far back as1936,Senate Document No.264warned Ame-ricans that the soils used to grow fruits and vegetables were seriously deﬁcient in needed minerals.Continu-ous cropping and the ravages of pollution were even then robbing the soil of the minerals needed to sustain life(Health Lifestyles Inc.,1993).Unlike the body’s complex organic compounds (carbohydrates,lipids,proteins,vitamins)that are used metabolically in the generation of energy,mine-rals are often found in the form of salts in the body that are inorganic and not metabolized(Carpenter et al.,2013).Minerals constitute about4to6percent of body weight—about one-half as Ca,one-quarter P as phosphates,and the remainder being made up of the other essential minerals that must be derived from the diet(Carpenter et al.,2013).Minerals not only impart hardness to bones and teeth but also function broadly in metabolism,e.g.,as electrolytes in controlling the movement of water in and out of cells,as components of enzyme systems,and as the constituents of many organic molecules(Carpenter et al.,2013).Mineral nutrition in humans is deﬁned as the pro-cess by which substances in foods are transformed into body tissues and provide energy for the full range of physical and mental activities that make up human life(Carpenter et al.,2013).The ultimate goal of nu-tritional science is to promote optimal health and re-duce the risk of chronic diseases,such as cardiovascular disease and cancer,as well as to prevent classic nu-tritional deﬁciency diseases,such as kwashiorkor and pellagra(Carpenter et al.,2013)MAJOR CROP AND ANIMAL SOURCES AND THEIR RECOMMENDED DAILY DOSESRecommended daily doses of all mineral nutrients stu-diedAll foods contain several mineral nutrients;ho-wever,some are higher in certain minerals than other minerals.The recommended doses vary considerably as established by various agencies related to regulation of mineral nutrients in various foods.A dietary requirement is deﬁned as the lowest con-tinuing intake of a nutrient that,for a speciﬁed indica-tor of adequacy,will maintain a deﬁned level of nutri-ture in an individual(Sutherland et al.,1998).An es-sential dietary component is one that the body can not synthesize in suﬃcient quantities to maintain health.SOURCES AND DEFICIENCY DISEASES OF MINEARL NUTRIENTS15Recommended dietary allowances are based on esti-mates of the dietary requirements,and are designed to prevent deﬁciency diseases and promote health through an adequate diet(Lenntech,1998).In1996, the Food and Nutrition Board(FNB)began a revi-sion process of the recommended dietary allowances using as criteria speciﬁc indicators of adequacy and functional end points for reducing the risk of chronic diseases.Boron is a dietary component,and evidence from animal studies indicates that it is a dietary essential; it can not be synthesized in tissues,and organisms ex-posed to very low levels of B show developmental de-fects(Lenntech,1998).Recommended daily dosages of various mineral nutrients are reported in Table I.It is evident that their amounts vary considerably.BoronThe average B concentration in the earth’s crust is17mg kg−1and most soils fall within the range of 3–100mg kg−1(Samir et al.,2011).In general,these amounts in soils are lower than most essential micronu-trients with the exception of Mo and Se.Deﬁciency of B has been found to aﬀect the physi-ology of human beings(Shaaban,2010).Boron may be beneﬁcial for bone growth and maintenance,cen-tral nervous system function,and the inﬂammatory response(Nielsen,2009).The best documented beneﬁ-cial eﬀect of B is on Ca metabolism and utilization,and thus aﬀects bone calciﬁcation and maintenance (Nielsen,1998a).The highest B concentration is found in bones,indicating one of the potential beneﬁts in its ability to protect humans from osteoporosis(Nielsen, 1998).It has been reported that B appears to lessen eﬀects of a low Mg-diet on body growth,serum choles-terol and ash concentration in bone,but exacerbate deﬁciency symptoms,without aﬀecting the Mg or Ca concentration in the serum(Kenny and McCoy,2000).The elevation of endogenous steroid hormones as a result of B supplementation suggests that B may be used as an ergogenic,safe substance for athletes,but needs further investigation(Naghii,1999).Boron sup-plementation also has been found to result in high B absorption eﬃciency and the elevation of endogenous estrogen suggests a protective role of B in atheroscle-rosis(Naghii and Samman,1997).In humans,there is evidence of homeostatic regulation of B;e.g.,human milk B concentrations are under apparent homeostatic control(Hunt,2007).Boron satisﬁes the criterion of essentiality and tissue B concentrations during short term variations in intake are maintained by homeo-static mechanisms(Hunt,2007).In most studies it has been found that B aﬀects human steroid hormone levels.Circulating testoste-rones and estradiol levels have been proposed to mo-dify prostate and cancer risk(Wiseman,2002).After controlling for age,race,smoking,body mass index, dietary caloric intake,and alcohol consumption,incre-TABLE IRecommended daily dosages a)of mineral nutrientsMineral nutrient Lenntech(1998)Wikipedia—The Free Balch and Balch(2000)Encyclopedia(2012)Boron(mg)20-3–6Calcium(mg)10001000–13001500–2000(as citrate or ascorbate) Chlorine(mg)3400(in chloride form)2300–3400-Chromium(μg)12035–120150–400(as glucose tolerance factor orpicolinate or polynicotinate)Copper(mg)20.9–22–3Fluoride(mg) 3.54-Iodine(mg)0.150.15100–225Iron(mg)151818–30Magnesium(mg)350400–420750–1000Manganese(mg)52–2.33–10Molybdenum(μg)7545–7530–100(as ascorbate or aspartate) Nickel(mg)<1--Phosphorus(mg)10001000-Potassium(mg)3500350099–500(as citrate)Selenium(μg)3570100–200Sodium(mg)24002400-Sulfur(mg)---Vanadium(mg)<1.8 1.80.2–1(as vanadyl sulfate)Zinc(mg)1511–1530–50a)A range of values from recommended daily intake to maximum recommended daily allowance of daily reference intakes.16U.C.GUPTA AND S.C.GUPTAased dietary B intake was generally associated with a decreased risk of prostate cancer with a dose-response pattern(Cui et al.,2004).When with the high B in-take,low dietary B resulted in signiﬁcantly poorer performance on tasks emphasizing manual dexterity, eye-hand coordination,attention,perception,encoding and short-term memory,and long-term memory.Col-lectively,the data from these studies indicate that B may play a role in human brain function and cognitive performance,and provide additional evidence that B is an essential nutrient for humans(Penland,1994).One of the reasons why many researchers think B helps treat arthritis is that it is essential for the strengthening of bones.Boron helps metabolize many bone strengthening minerals like Ca,Cu and Mg(Sti-panuk and Caudill,2012).There is also evidence that B provides several health beneﬁts to the brain.It is widely believed that B can positively inﬂuence a di-verse set of brain functions including memory,concen-tration,and even hand-eye coordination(Stipanuk and Caudill,2012).Data on dietary B intake by human beings are fairly sparse.Boron is not included in the United States Department of Agriculture nutrient databases,and no comprehensive analytical database exists on the B con-tent of speciﬁc foods.In an American study,the B levels were slightly higher in vegetarian adults than in the general population(Rainey et al.,1999).It was stated that the top two B contributors,coﬀee and milk, are low in B,yet they make up12%of the total B in-take by virtue of the volume consumed.Peanut butter, wine,raisins,apples,pears,grapes,avocados,legumes, peanuts and other nuts are good sources of B(Rainey et al.,1999;Stipanuk and Caudill,2012).Diets low in fruits,vegetables,legumes and nuts may not provide an adequate amount of B.CalciumCalcium is theﬁfth most abundant element by mass in the earth’s crust.It is everywhere on the planet,and this common mineral provides a number of health beneﬁts to the human body(Stipanuk and Caudill,2012).Most well-known health beneﬁt of Ca is the important part it plays in developing strong bones. Almost all the body’s Ca can be found in the bones and teeth,and there are countless studies which show that proper Ca intake helps young people develop strong bones while keeping the bones of older people strong and healthy.It also helps to prevent and treat a vari-ety of bone-related illnesses,such as osteoporosis(Sti-panuk and Caudill,2012).In addition to fulﬁlling the needs for Ca ions re-quired in numerous intracellular functions as well as for the regulation of blood clotting(hemostasis),prac-tically all of the body’s remaining Ca exists in skele-tal salts that support the body,enable ambulation, and protect internal organs.Aﬁxed amount of Ca forms the teeth which,after formation,remains static in the oral cavity and which,unlike the bones,do not participate in Ca metabolism(Anderson and Garner, 2011).Following the achievement of peak bone mass in the second or third decade of life,dietary Ca is needed to replace Ca lost from bone tissue as part of the normal dynamic turnover of the skeleton.Adult bone mineral content and bone mineral density are better maintained by an adequate amount of Ca in the diet(Anderson and Garner,2011).Dietary supplement use is associated with a higher prevalence of groups meeting the adequate intake for Ca and vitamin D.Monitoring usual total nutrient in-take is necessary to adequately characterize and evalu-ate the population’s nutritional status and adherence to recommendations for nutrient intake(Bailey et al., 2010).Knowledge of osteoporosis and the importance of dietary intake of Ca and vitamin D did improve after the intervention(Bohaty et al.,2008).Osteoporosis is a painful,disabling illness and its prevention is a lifelong process.Older women may suﬀer its devastating eﬀects because of these nutrient deﬁciencies in their diet as young adult women(Bohaty et al.,2008).Epidemio-logical and prospective studies have related vitamin D deﬁciency not only to osteoporosis but also to cardio-vascular disease,diabetes,cancer,infection and neu-rodegenerative disease(P´e rez-L´o pez et al.,2012).In a study in Japan,an excessive intake of400mg Ca-fortiﬁedﬁsh sausage,a special health food in Japan, appeared to be a safe means to obtain the daily Ca requirement(Murota et al.,2010).Inadequate sunlight exposure and Ca intake during rapid growth at puberty lead to hypocalcemia,hypovi-taminosis D and eventually to overt rickets(Dahifar et al.,2007).It was concluded that low daily Ca intake and vitamin D acquirement are two important prob-lems in Iranian girls during rapid growth at puberty; therefore,for prevention of overt rickets,Ca and vita-min D supplementation appears to be necessary(Dahi-far et al.,2007).In a study involving the mean daily Ca intake at553mg d−1,along with other minerals in pregnant women,it was found that only Ca intakes were signiﬁcantly correlated to birth weight(Denguezli et al.,2007).In a US study,milk and milk products were by far the lowest-cost sources of dietary Ca and also were among the lowest-cost sources of riboﬂavin and vita-SOURCES AND DEFICIENCY DISEASES OF MINEARL NUTRIENTS17min B12(Drewnowski,2011).An intake of approxi-mately1500mg Ca d−1could aid in the management of body and truncal fat.It has been recommended that young adults be encouraged to increase their total Ca intakes to at least the recommended daily allowance of 1000mg d−1for reasons extending beyond bone health (Skinner et al.,2011).The tolerable upper Ca intake level ranges from1000to3000mg d−1,based on Ca excretion or kidney stone formation,and vitamin D from1000to4000international units daily,based on hypercalcemia adjusted for uncertainty resulting from emerging risk relationships(Ross et al.,2011).Due to the nutrient synergy of foods,dietary Ca sources should continue to be promoted in nutritional counselling eﬀorts as the optimal method of obtaining adequate Ca(French et al.,2008).Nutrition education should emphasize strategies to decrease the side eﬀects associated with Ca-rich foods and alleviate concerns re-garding the cholesterol and fat content of some Ca-rich foods.In addition to strategies to increase consump-tion of dietary Ca sources,supplementation should be considered as an acceptable method of increasing Ca intake among women with low bone mineral den-sity(French et al.,2008).In a study in USA,African Americans in all age groups did not meet dairy re-commendations from the2005US Dietary Guidelines and the2004National Medical Association(Fulgoni III et al.,2007).Calcium and Zn intakes in Australian children from core foods were below70%of the recommended dietary intakes for adolescent girls(Rangan et al.,2008).It was concluded that the extra foods are over-consumed at two to four times the recommended limits and con-tribute excessively to the energy,fat and sugar intakes of Australian children,while providing relatively few micronutrients,including Ca(Rangan et al.,2008).Milk,cheese and most other dairy products,beans (Phaseolus vulgaris),broccoli(Brassica olereracea var. italica)kale(Brassica oleracea var.acephala),collards (Brassica oleracea hardiness)and raisins are some of the best sources of Ca(Stipanuk and Caudill,2012).ChlorideDrinking water disinfection has been shown to be an important public health measure since the turn of the century.In USA,it was perhaps the single most important factor in controlling typhoid fever,a water-borne disease that was rampant throughout the world during the last century(Akin et al.,1982).Disinfec-tion was important in limiting diseases,such as cholera, amoebiasis,salmonellosis,and hepatitis A(Akin et al., 1982).Still,despite its beneﬁcial eﬀects and lifesaving reputation,other chlorine eﬀects on health and envi-ronment are dangerous to humans(Conjecture Corpo-ration,2003).Chlorine is essential for bodyﬂuid regulations in humans(Evans and Solberg,1998)and exists in the safe,inorganic form as the negative chloride ion as NaCl(Belkraft,2005).But when Cl reacts with organic compounds in the water,it produces poisonous che-mical compounds,which cause cancer and other health problems(Belkraft,2005).Following inhalation and skin or eye contact,exposure to HCl acid is toxic by ingestion and skin or eye exposure(Bul,2011).It has been hypothesized that organochlorine pesticides may be associated with the increased incidence of breast cancer in women and decreased sperm concentrations and reproductive problems in men(Safe,1995).Ho-wever,elevation of some organochlorine compounds in breast cancer patients is not consistently observed (Safe,1995).Methyl chloride is very toxic;mice ex-posed to high levels of methyl chloride by inhalation for two years had an elevated incidence of liver and lung tumors(Green,1997).The mouse seems to be unique in its response to methyl chloride and thus it is an inappropriate model to assess human health(Green, 1997).The data from Bangladesh showed that the ma-rine salt deposition is signiﬁcant up to a distance of about200m from the seashore and from this point onward,the amount of chlorides drops sharply(Hos-sain and Said,2011).Chloride exists in aqueous solu-tions as a monovalent anion and its salts are readily soluble.Consequently,it is not absorbed by organic matter or clay in most soils,and does not readily pre-cipitate out of solution(Hossain and Said,2011).For these reasons,Cl is mobile in the soil and is readily leached where rainfall and/or irrigation exceeds evapo-transpiration.Chloride is one of theﬁrst elements re-moved from minerals by soil weathering processes.This is why most of the world’s Cl is found in oceans or in salt deposits left by evaporation from old inland seas (International Plant Nutrition Institute,2012).Many soils and crops receive more than an adequate supply of Cl from sea spray carried by rain and snow.This diminishes rapidly with the distance from the ocean (International Plant Nutrition Institute,2012).Results from disinfecting student health centres (SHCs)in Taiwan suggested that the air quality guide-lines prescribed by the Taiwan Environmental Protec-tion Agency for SHCs and other healthcare facilities can best be achieved by applying chlorine dioxide at regular(daily)intervals(Hsu et al.,2012).The results from southern Italy on ground water provided valuable18U.C.GUPTA AND S.C.GUPTAinactivation constants of cultural indicators,e.g.,co-liforms,enterococci,Clostridium spores and viruses in the wastewater that have been injected into the fra-ctured aquifer since1991(Masciopinto et al.,2007). Hypochlorination reduces somatic coliphages and Clo-stridium spores in groundwater but did not achieve complete inactivation in all tests.It was concluded that complete disinfection of groundwater samples was pos-sible only when there was an initial count of Clostrid-ium spores of≤10colony-forming units100mL−1 (Masciopinto et al.,2007).It has been reported that naturally occurring indicator bacteria and bacterio-phages respond diﬀerently to chlorination in drin-king water distribution networks in northeastern Spain (Mendez et al.,2004).Though several chlorinated organic compounds are produced by humans,some are also produced by the biotic and abiotic processes in the environment(My-neni,2002).These carcinogenic and toxic compounds are formed at rapid rates from the transformation of in-organic Cl during humiﬁcation of plant material,thus playing a critical role in Cl cycling,and from the trans-formation of several major and trace elements in the environment and may inﬂuence human health(My-neni,2002).Chlorinated drinking water is one of the chief source of Cl.Disinfection with chlorine is one of the safest way of limiting the number of diseases known to be capable of waterborne transmission,e.g.,cholera, amoebiasis,salmonellosis and hepatitis A(Akin et al., 1982).ChromiumChromium is an essential trace mineral that hu-mans require in trace amounts.In1959,Cr wasﬁrst identiﬁed as an element that enables the hormone in-sulin to function properly(Wong,2012).Since then, Cr has been studied for diabetes and has become a po-pular dietary supplement(Wong,2012).Chromium is essential for maintaining health and has many uses and applications in the human body.For instance,there is a great deal of research that suggests that Cr is beneﬁcial to those with impaired glucose tolerance(Stipanuk and Caudill,2012).Impaired glucose tolerance,which is a precursor to type2diabetes for about25%of those who acquire it,is a state in between the glucose levels of dia-betes and normal glucose levels.A meta-analysis on the relationship between Cr and impaired glucose tolerance found that12of the15studies showed a positive eﬀect (Stipanuk and Caudill,2012).The pooled data from the studies using chromium picolinate(CrPic)supple-mentation for type2diabetes mellitus subjects showed substantial reductions in hyperglycemia and hyperin-sulinemia,which equate to a reduced risk for disease complications(Broadhurst and Domenico,2006).Col-lectively,the data support the safety and therapeutic value of CrPic for the management of cholesterolemia and hyperglycemia in subjects with diabetes(Broad-hurst and Domenico,2006).Tissue Cr levels of subjects with diabetes are lower than those of normal control subjects,and a correla-tion exists between low circulating Cr levels and the incidence of type2diabetes(Hummel and Schnell, 2009).However,supplementation with Cr has been shown to reduce insulin resistance and to help reduce the risk of cardiovascular disease and type2diabetes (Hummel and Schnell,2009).The eﬀect of Cr treat-ment on glycemic control in a Western population of insulin-dependent patients with type2diabetes using high-dose Cr treatment showed no evidence that it was eﬀective in obese patients with type2diabetes (Kleefstra et al.,2006).There is evidence of hormonal eﬀects of supplemental Cr besides the eﬀect on in-sulin.Chromium supplementation does result in tis-sue retention,especially in the kidneys,although no pathogenic eﬀect has been demonstrated despite con-siderable study(Lamson and Plaza,2002).In two cases,one involving a diabetic patient and the other a non-diabetic patient,Cr administration appeared to decrease insulin requirements.Infusion of chromic chloride appeared to reduce insulin requirements in one diabetic patient and one non-diabetic patient(Phung et al.,2010).Chromium deﬁciencies result in decreased insulin sensitivity,glucose intolerance and increased risk of diabetes.In a French study,the Cr status decreased with age,suggesting that the elderly may be at a high risk of Cr deﬁciency(Roussel et al.,2007).Although these subjects had well-balanced diets,their daily Cr intakes did not reach the French recommendations.It is likely that the low Cr intakes were due to the low Cr density of the foods.A negative correlation was found between Cr intakes and insulin,body mass index and leptin(Roussel et al.,2007).Of all the“essential”elements,the role of Cr is un-doubtedly the most controversial.Recently,its status as an essential element,ﬁrst proposed nearly60year ago,has been challenged;this challenge will probably result in the general consensus on the status changing (Stallings and Vincent,2006).These new researchers were attracted to theﬁeld by the rapidly expanding po-pular attention received by Cr nutritional supplements, which was not being mirrored by scientiﬁc advances in understanding how these supplements could work at a。

GRE阅读真题精讲之OGPassage14-16

GRE阅读真题精讲之OGPassage14-16对于GRE阅读部分来说，大家可以先从官方指南开始备考。

这样对大家之后的复习方向有更好的帮助。

下面小编就为经典整理了OG 内容，供大家参考训练。

GRE阅读真题之OG Passage 14OG-1Passage 14Whether the languages of the ancient American peoples were used for expressing abstract universal concepts can be clearly answered in the case of Nahuatl. Nahuatl, like Greek and German, is a language that allows the formation of extensive compounds. By the combination of radicals or semantic elements, single compound words can express complex conceptual relations, often of an abstract universal character.The tlamatinime (those who know) were able to use this rich stock of abstract terms to express the nuances of their thought. They also availed themselves of other forms of expression with metaphorical meaning, some probably original, some derived from Toltec coinages. Of these forms, the most characteristic in Nahuatl is the juxtaposition of two words that, because they are synonyms, associated terms, or even contraries, complement each other to evoke one single idea. Used metaphorically, the juxtaposed terms connote specific or essential traits of the being they refer to, introducing a mode of poetry as an almost habitual form of expression.For the following question, consider each of the choices separately and select all that apply.1. Which of the following can be inferred from the passage regarding present-day research relating to Nahuatl?A. Some record or evidence of the thought of the tlamatinime is available.B. For at least some Nahuatl expressions, researchers are able to trace their derivation from another ancient American language.C. Researchers believe that in Nahuatl, abstract universal concepts are always expressed metaphorically.2. Select the sentence in the passage in which the author introduces a specific Nahuatl mode of expression that is not identified as being shared with certain European languages.3. In the context in which it appears, “coinages” (line 9) most nearly meansA. adaptationsB. creationsC. idiosyncrasiesD. pronunciationsE. currenciesGRE阅读真题之OG Passage 15OG-1Passage 15At a certain period in Earth’s history, its atmosphere contained almost no oxygen, although plants were producing vast quantities of oxygen. As a way of reconciling these two facts, scientists have hypothesized that nearly all of the oxygen being produced was taken up by iron on Earth’s surface. Clearly, however, this explanation is inadequate. New studies show that the amount of iron on Earth’s sur face was not sufficient to absorb anywhere near as much oxygen as was being produced. Therefore, something in addition to the iron on Earth’s surface must have absorbed much of the oxygen produced by plant life.1. In the argument given, the two portions in boldface playwhich of the following roles?A. The first is a claim made by the argument in support of a certain position; the second is that position.B. The first is a judgment made by the argument about a certain explanation; the second is that explanation.C. The first expresses the argument’s dismissal of an objection to the position it seeks to establish; the second is that position.D. The first sums up the argument’s position with regard to a certain hypothesis; the second provides grounds for that position.E. The first is a concession by the argument that its initial formulation of the position it seeks to establish requires modification; the second presents that position in a modified form.GRE阅读真题之OG Passage 16OG-1Passage 16Animal signals, such as the complex songs of birds, tend to be costly. A bird, by singing, may forfeit time that could otherwise be spent on other important behaviors such as foraging or resting. Singing may also advertise an individual’s location to rivals or predators and impair the ability to detect their approach. Although these types of cost may be important, discussions of the cost of singing have generally focused on energy costs. Overall the evidence is equivocal: for instance, while Eberhardt found increases in energy consumption during singing for Carolina wrens, Chappell found no effect of crowing on energy consumption in roosters.To obtain empirical data regarding the energy costs ofsinging, Thomas examined the relationship between song rate and overnight changes in body mass of male nightingales. Birds store energy as subcutaneous fat deposits or “body reserves”; changes in these reserves can be reliably estimated by measuring changes in body mass. If singing has important energy costs, nightingales should lose more body mass on nights when their song rate is high. Thomas found that nightingales reached a significantly higher body mass at dusk and lost more mass overnight on nights when their song rate was high.These results suggest that there may be several costs of singing at night associated with body reserves. The increased metabolic cost of possessing higher body mass contributes to the increased overnight mass loss. The strategic regulation of evening body reserves is also likely to incur additional costs, as nightingales must spend more time foraging in order to build up larger body reserves. The metabolic cost of singing itself may also contribute to increased loss of reserves. This metabolic cost may arise from the muscular and neural activity involved in singing or from behaviors associated with singing. For example, birds may expend more of their reserves on thermoregulation if they spend the night exposed to the wind on a song post than if they are in a sheltered roost site. Thomas’s data therefore sho w that whether or not singing per se has an important metabolic cost, metabolic costs associated with singing can have an important measurable effect on a bird’s daily energy budget, at least in birds with high song rates such as nightingales.1. The primary purpose of the passage is toA. compare the different types of cost involved for certain birds in singingB. question a hypothesis regarding the energy costs ofsinging for certain birdsC. present evidence suggesting that singing has an important energy cost for certain birdsD. discuss the benefits provided to an organism by a behavior that is costly in energyE. describe an experiment that supports an alternative model of how birdsong functionsFor the following question, consider each of the choices separately and select all that apply.2. The passage implies that during the day before a night on which a male nightingale’s song rate is high, that nightingale probably does which of the following?A. Expends less of its reserves on thermoregulation than on other daysB. Stores more energy as body reserves than on other daysC. Hides to avoid predators3. Select the sentence in the first or second paragraph that presents empirical results in support of a hypothesis about the energy costs of singing.For the following question, consider each of the choices separately and select all that apply.4. It can be inferred from the passage that compared with other costs of singing, which of the following is true of the energy costs of singing?A. They are the single greatest cost to an individual bird.B. They have generally received more attention from scientists.C. They vary less from one bird species to another.GRE官方指南(OG)中的阅读真题答案Passage 第一题第二题第三题第四题14 AB “Of … idea.” B15 D16 C B “Thomas … high.” B GRE阅读真题精讲之OG Passage 14-16。

the oxford handbook of translation studies

the oxford handbook of translation studiesThe Oxford Handbook of Translation Studies is a comprehensive and authoritative resource for scholars and students in the field of translation studies. This handbook offers a wide range of essays and articles written by leading experts in the field, covering various aspects of translation theory, practice, and research.One of the key features of this handbook is its interdisciplinary approach. It brings together contributions from scholars in fields such as linguistics, literature, cultural studies, and sociology, providing a holistic understanding of translation as a complex and multifaceted phenomenon. This interdisciplinary perspective allows for a deeper exploration of the cultural, social, and political implications of translation, highlighting its role in shaping and mediating cross-cultural interactions.Another notable aspect of this handbook is its focus on both theoretical and practical aspects of translation. It covers a wide range of topics, including translation theories, translation history, translation and technology, translationand gender, translation ethics, and translation pedagogy. This comprehensive coverage ensures that readers get a well-rounded understanding of the field and its various dimensions.Furthermore, this handbook also pays attention to the emerging trends and challenges in translation studies. It explores the impact of globalization, digitalization, and new media on translation practices, highlighting the need for translators to adapt to the changing landscape of the profession. It also addresses the ethical dilemmas faced by translators, such as issues of cultural appropriation and the power dynamics inherent in translation.In addition to its breadth and depth of coverage, the Oxford Handbook of Translation Studies also stands out for its rigorous scholarship and critical analysis. The essays included in this handbook are carefully researched and draw on a wide range of sources, making them valuable resources for both scholars and students. The critical approach taken by the authors encourages readers to question established norms and assumptions, stimulating further research and debate in the field.Overall, the Oxford Handbook of Translation Studies is an indispensable resource for anyone interested in translation studies. Its interdisciplinary approach, comprehensive coverage, and critical analysis make it a valuable tool for scholars, students, and practitioners alike. Whether one is a beginner exploring the field or an experienced researcher looking for new insights, this handbook offers a wealth of knowledge and perspectives to engage with.。

Academia_and_the_Market

News that the 2012 Nobel Prize in Literature was awarded to Chinese writer Mo Y an was understandably considered a triumph marked by wide celebrations in China thatcaught publishers off-guard. Mo’s novels instantly sold out at every major bookstore. After five days of empty shelves, Shanghai Book City, the largest bookstore in Shanghai, eventually received 8,000 copies of Mo Yan’s Novel Collection, published hurriedly by Shanghai Lit-ACADEMIA and the MARKETText by Chong YatuA display especially for Mo Yan’s work becomes the highlight of a bookstore. CFPerature and Art Publishing House due to the spike in demand. Because of the time crunch, the publisher even failed to tag the cover with coveted promotional words “Nobel Prize Laureate in Literature.”Mo is recognized as an inflential figure in modern Chinese literature, but his work performed modestly in both publication and circulation due to the au-thor’s preference for heavy topics and complex ideas embedded in his descriptions. As a result, domestic publishers were never willing to risk financial futures on extensive promotion and publication of his work. Shanghai Book City, for example, retained a monthly stock of only a hundred copies of Frog, one of Mo’s best-selling novels.This provides a window into the Chinese publish-ing industry, which seems hesitant to promote deeperliterature that questions reality. Readers of heavier lit-erature have steadily decreased, so publishers are not optimistic about the market potential of this genre of book. On the other hand, such work’s lofty position in literary circles makes it hard to abandon. So, differ-ent sectors of the industry have made different choices with critically-acclaimed literature.Profit-Driven PublishersMai Jia is a celebrated Chinese writer who has seen rocketing market value in recent years after sev-eral of his books were adapted into popular TV se-ries. In 2010, he revealed a personal anecdote: Y ears ago, when he had just begun writing Wind Whisperer, which would later be adapted into another TV drama, a publisher visited his home three times, offering the astronomical figure of 5 million yuan for the rights to the book, but was rejected each time. Mai couldn’t un-derstand why the publisher was offering such a high price without even reading the manuscript. He sur-mised that some publishers were so profit-driven that they prefer mediocre work by a famous writer to an excellent book by an unknown author.Mai’s experience testifies to a phenomenon in con-temporary Chinese publishing. Fierce market compe-tition has resulted in a tendency of some publishers to seek only profits, ignoring social value. Therefore, “pure” literature, sated with critical realism and socialvalue, has become marginalized to some extent. In or-der to improve marketing, they brainstorm a plethoraof tactics. In 2009, when Mo Yan’s full-length novelFrog was released in Shanghai, the publishing houseinvited celebrity novelist Guo Jingming, who wasborn in the 1980s, to the ceremony, hoping to attractthe younger writer’s fans to Mo’s work. The market-ing move truly embarrassed Mo, who had alreadyachieved fame before Guo was born. He didn’t mincewords when stating his disgust that sales of Frog reliedon help from Guo. However, the tastes of the currentmarket pressure publishers to treat academic literatureas such.Many Chinese literary heavyweights have sighed atthe state of the craft. Some critics point out that exter-nal factors are responsible for the fact that most cur-rent Chinese bestsellers have little literary value, andsome even contain negative information that couldmislead the public. Since the demands of the markethave largely replaced academic literary criteria, manywriters believe both the number of high-caliber writersand the quality of Chinese writing are in a free fall. Struggling JournalsIn China, authors traditionally cherish literaryjournals passionately. Many literaryheavyweightsMo Yan’s workdisplayed atFrankfurt BookFair 2012.ICearned fame through periodical magazines, which they believe contribute significantly to the survival and de-velopment of Chinese literature.Today, however, due to dwindling readership, many Chinese literary journals are facing hard times. Pressured by financial difficulties, the renowned liter-ary magazine Master began accepting paid articles, a move which ultimately resulted in its closure and reor-ganization.Tightly-budgeted literary magazines like Master once abounded. According to Zhang Shengyou, sec-retary of the Secretariat of Chinese Writers Associa-tion, China has more than 9,000 journals of various types, and 10 percent are literary magazines, which are mostly endangered.In contrast, the literature boom of the 1980s and 90s remains a crystal clear memory for many Chinese writers. Chen Dongjie, deputy editor-in-chief of Octo-ber magazine, describes the period as a “crazy golden age” for writers and readers alike. “Back then, liter-ary journals were almost positioned as the mainstream media,” he recalls. “Writers, like today’s entertainment stars, developed loyal followings, and magazines, like iPhones today, were snapped up immediately when they hit newsstands. Chinese language and literature departments in universities only admitted top scoring students.” As the public’s reading interests change, lit-erary journals have been left with little demand from the market.Despite the difficult situation, some journals aren’t ready to throw in the towel. In their eyes, a nation’s ac-ademic literature is iconic, responsible for promoting, representing, and developing culture while protecting literary art from commercialization. Qiu Huadong, assistant to the editor-in-chief of People’s Literature, once said, “We will never surrender to market, but will stand by high-class literature. Our goal is to improve this strategy and attract more high-end readers to fall in love with pure literature.”To this end, some magazines are attempting to expand the influence of pure literature and elevate public aesthetic taste. In May 2010, Harvest , a liter-ary magazine with a monthly circulation of 100,000,raised its contribution fee to 400 - 500 yuan for everyWhen Red Sorghum , an adaptation of Mo Yan’s novel, was filmed, the female lead Gong Li (center) posed with the author and his family.When Mo Yan’s full-length novelFrog was re-leased, the pub-lishing house invited popular young writer Guo Jingming to the ceremony to helppublicity. CFP1,000 characters, drawing considerable attention. Oc-tober, another example, regularly organizes meetings between authors and readers to facilitate communi-cation. However, just how much such moves help the academic literature industry is unknown.Newspaper DilemmasChinese literature enthusiasts have likely noticed that except for major newspapers like People’s Daily and Xinmin Evening News , which still publish literary articles, many regional papers have reshaped or even cut their literature sections.Newspapers’ current attitudes towards literature sharply contrast those at the end of last century, when authors and literary works were the highlight of most Chinese newspapers. Newer papers established special columns devoted to publishing novels and poems. Lit-erary content was regarded as a top criterion in judg-ing the quality of a newspaper. In that era, a wealth of outstanding essays and novels were immortalized through the pages of newspapers, such as A Bitter Journey of Culture by Yu Qiuyu, Ordinary WorldbyLu Yao, and Brothers by Yu Hua.Some industry experts attribute the dramatic change to the contrast between the patient pace of lit-erature and the “fast facts” tone of newspapers. When reading preferences of a society as a whole change, market-sensitive newspapers have to adjust. Others hy-pothesize about the cold relationship between writers and media, suggesting that academic literary masters are rarely interested in participating in promotional campaigns, whereas other writers are not really pre-ferred by media and readers. As a result, newspapers gradually lost their literary flavor.Eminent writer Wang Meng strongly called for the revival of literature in newspapers, asserting that “Newspapers’ literature editions should capitalize ontheir advantages, unite authors, discover new talent, and create a land where literature can flourish.”Mo Yan’s Nobel Prize in Literature has undoubt-edly reignited Chinese interest in literature and renewed newspapers’ taste for literature as well. In addition tomany pages covering Mo’s biography and work, some domestic newspapers have already announced plans to restore or expand their literature editions. Mo Yan (right)and writer WangAnyi attend a symposiumthemed, “Writing: The Most For-midable Resis-tance.” A greatnumber of Chi-nese writers havetaken action tosave academicliterature fromdecline. CFP。

文明意味着什么英语作文

Civilization is a complex concept that encompasses a wide array of social, cultural, and behavioral norms. It is often seen as the pinnacle of human development, representing progress and advancement in various aspects of life. Here is an essay on what civilization means in English:The Essence of CivilizationCivilization is not merely a state of technological advancement or a collection of societal structures it is a reflection of the collective values, ethics, and behaviors that define a society. It is a tapestry woven from the threads of history, culture, and human interaction, representing the best and worst of our species.Historical PerspectiveFrom the ancient civilizations of Mesopotamia and Egypt to the modern metropolises of today, civilization has always been a testament to human ingenuity and ambition. It is through civilization that we have built grand structures, developed complex languages, and created systems of governance and trade. Yet, it is also through civilization that we have seen the rise of conflict, inequality, and environmental degradation.Cultural DimensionsAt its core, civilization is a cultural phenomenon. It is the shared beliefs, customs, and practices that give a society its identity. This includes art, literature, music, and other forms of creative expression that not only entertain but also educate and inspire. Civilization is the crucible in which diverse cultures interact, influencing and enriching one another.Social ConstructsCivilization is also a framework of social constructs. It includes the development of laws, education systems, and social norms that guide behavior and maintain order. These constructs are not static they evolve with societal needs and values, adapting to the changing landscape of human experience.Ethical ConsiderationsA crucial aspect of civilization is its ethical dimension. It is the embodiment of ourcollective moral compass, guiding us towards a more just and equitable society. This includes the recognition and respect for human rights, the promotion of peace, and the pursuit of social justice.Technological MilestonesWhile not the defining feature, technology is an integral part of civilization. It is through technological advancements that we have been able to overcome many of the challenges faced by earlier societies. From the wheel to the internet, technology has shaped the way we live, work, and communicate.Environmental StewardshipIn recent times, civilization has come to include the recognition of our responsibility towards the environment. Sustainable practices and the conservation of natural resources are now seen as essential components of a civilized society.ConclusionIn essence, civilization is a multifaceted concept that goes beyond material progress. It is the embodiment of our collective aspirations for a society that is not only technologically advanced but also ethically sound, culturally rich, and socially just. It is a continuous journey of growth and selfimprovement, a pursuit that defines the human spirit.This essay aims to capture the multidimensional nature of civilization, highlighting its significance beyond mere material achievements to include the cultural, social, and ethical aspects that truly define a civilized society.。

适合高中生拓展阅读的英语美文

新东方优美背诵短文50篇 Unit50:CellsandTemperature50. Cells and TemperatureCells cannot remain alive outside certain limits of temperature and much narrower limits mark the boundaries of effective functioning. Enzyme systems of mammals and birds are most efficient only within a narrow range around 37C;a departure of a few degrees from this value seriously impairs their functioning. Even though cells can survive wider fluctuations the integrated actions of bodily systems are impaired. Other animals have a wider tolerance for changes of bodily temperature.For centuries it has been recognized that mammals and birds differ from other animalsin the way they regulate body temperature. Ways of characterizing the difference havebecome more accurate and meaningful over time, but popular terminology still reflectsthe old division into “warm-blooded warm-blooded”” and “cold-blooded cold-blooded”” species; warm-bloodedincluded mammals and birds whereas all other creatures were considered cold-blooded.As more species were studied, it became evident that this classification was inadequate. A fence lizard or a desert iguana —each cold-blooded----usually has abody temperature only a degree or two below that of humans and so is not cold. Thereforethe next distinction was made between animals that maintain a constant bodytemperature, called home0therms, and those whose body temperature varies with theirenvironments, called poikilotherms. But this classification also proved inadequate,because among mammals there are many that vary their body temperatures duringhibernation. Furthermore, many invertebrates that live in the depths of the ocean never experience change in the depths of the ocean never experience change in the chill of the deep water, and their body temperatures remain constant.细胞与温度细胞只能在一定的温度范围内存活，而进一步保证它们有效工作的温度范围就更小了。

支持国货的作文有哪些英语

Supporting domestic products is a topic that can be approached from various angles in an essay. Here are some ideas and points that you can include in an essay about supporting domestic goods:1. Introduction to the Importance of Supporting National GoodsBegin with a brief introduction about why its important to support products made in ones own country.2. Economic BenefitsDiscuss how supporting domestic products can boost the local economy, create jobs, and reduce unemployment.3. Preservation of Traditional IndustriesHighlight the role of domestic products in preserving traditional industries and artisanal crafts that might otherwise be lost due to globalization.4. Quality and ReliabilityArgue that domestic products often have a reputation for quality and reliability, as they are made with local materials and cater to the specific needs of the local market.5. Cultural SignificanceExplain the cultural significance of supporting local products, as they often reflect the history and identity of a nation.6. Environmental ConsiderationsPoint out that buying local can reduce the carbon footprint associated with transportation and shipping of goods from overseas.7. Consumer Awareness and EducationEmphasize the need for consumers to be aware of the origins of the products they purchase and the impact of their choices on the economy and society.8. Government Policies and IncentivesDiscuss how governments can encourage the consumption of domestic products through policies, incentives, and campaigns.9. Challenges and SolutionsAddress the challenges faced by domestic industries, such as competition from cheaper imports, and suggest solutions like improving quality, innovation, and marketing strategies.10. Case StudiesProvide examples of successful domestic products or companies that have thrived due to consumer support and government policies.11. The Role of TechnologyDiscuss how technology can be used to improve the production and marketing of domestic products, making them more competitive in the global market.12. ConclusionSummarize the key points made in the essay and reiterate the importance of supporting domestic products for the overall wellbeing of the nation.Remember to use a clear and concise language, provide evidence or examples to support your arguments, and maintain a logical flow throughout the essay.。

needham research institute series 科学史文献系列

needham research institute series 科学史文献系列Needham Research Institute Series: A Collection of Scientific History LiteratureThe Needham Research Institute Series is a valuable collection of scientific history literature that explores various aspects of human scientific achievements throughout history. This series offers readers a comprehensive understanding of the development and progress in different scientific fields, shedding light on the contributors, discoveries, and advancements that have shaped our world.In this series, we delve into a wide range of topics, including but not limited to mathematics, physics, chemistry, biology, astronomy, and engineering. Each volume is carefully curated to provide readers with accurate and detailed information, allowing them to embark on a journey through time and witness the fascinating evolution of scientific thought and knowledge.One of the highlights of the Needham Research Institute Series is its meticulous research and presentation of historical accounts. The authors have meticulously examined primary sources, letters, scientific papers, and other archival materials to ensure accuracy and authenticity. This attention to detail allows readers to gain deeper insights into the minds and lives of the scientists who made groundbreaking contributions to their respective fields.Moreover, the series goes beyond simply recounting historical events; it also provides critical analysis andcontextualization of scientific developments. By exploring the social, cultural, and political factors that influenced scientific progress, readers can develop a more nuanced understanding of the complexities involved in scientific discovery. This interdisciplinary approach enhances the series' value, making it an essential read for both specialists and enthusiasts of scientific history.Additionally, the Needham Research Institute Series features a diverse range of contributors, including experts from various academic disciplines. This diversity ensures a multidimensional perspective, enriching the overall content of the series. Readers can benefit from the expertise and unique insights provided by these contributors, gaining a comprehensive understanding of the historical context and significance of scientific breakthroughs.In conclusion, the Needham Research Institute Series is an invaluable collection of scientific history literature. Its wide-ranging topics, meticulous research, critical analysis, and diverse contributions make it an essential resource for anyone interested in the fascinating evolution of scientific thought and knowledge. By delving into this series, readers can gain a deeper appreciation for the scientists and their contributions, as well as a broader understanding of the factors that shaped our world. The Needham Research Institute Series is a testament to the timeless pursuit of knowledge and serves as a guide for future scientific advancements.。

【英文读物】A Roving Commission

【英文读物】A Roving CommissionPREFACEHorrible as were the atrocities of which the monsters of the French Revolution were guilty, they paled before the fiendish outrages committed by their black imitators in Hayti. Indeed, for some six years the island presented a saturnalia of massacre, attended with indescribable tortures. It may be admitted that the retaliation inflicted by the maddened whites after the first massacre was as full of horrors as were the outrages perpetrated by the blacks, and both were rivalled by the mulattoes when they joined in the general madness for blood. The result was ruin to all concerned. France lost one of her fairest possessions, and a wealthy race of cultivators, many belonging to the best blood of France, were annihilated or driven into poverty among strangers. The mulattoes, many of whom were also wealthy, soon found that the passions they had done so much to foment were too powerful for them; their position under the blacks was far worse and more precarious, than it had been under the whites. The negroes gained a nominal liberty. Nowhere were the slaves so well treated as by the French colonists, and they soon discovered that, so far from profiting by the massacre of their masters and families, they were infinitely worse off than before. They were still obliged to work to some extent to save themselves from starvation; they had none to look to for aid in the time of sickness and old age; hardships and fevers had swept them away wholesale; the trade of the island dwindled almost to nothing; and at last the condition of the negroes in Hayti has fallen to the level of that of the savage African tribes. Unless some strong white power should occupy the island and enforce law and order, sternly repress crime, and demand a certain amount of labour from all able-bodied men, there seems no hope that any amelioration can take place in the present situation.G. A. HENTY.CHAPTER I A FIGHT WITH A BLOODHOUNDNow, look here, Nathaniel—""drop that, Curtis, you know very well that I won't have it. I can't help having such a beast of a name, and why it was given me I have never been able to make out, and if I had been consulted in the matter all the godfathers and godmothers in the world wouldn't have persuaded me to take such a name. Nat I don't mind. I don't say that it is a name that I should choose; still, I can put up with that, but the other I won't have. You have only just joined the ship, but if you ask the others they will tell you that I have had at least half a dozen fights over the name, and it is an understood thing here that if anyone wants a row with me he has only got to call me Nathaniel, and there is no occasion for any more words after that."The speaker was a pleasant-faced lad, between fifteen and sixteen, and his words were half in jest half in earnest. He was a general favourite among his mess-mates on board H. M. frigate Orpheus. He was full of life and fun, excep[Pg 2]tionally good-tempered, and able to stand any amount of chaff and joking, and it was understood by his comrades that there was but one point that it was unsafe to touch on, and that sore point was his name. It had been the choice of hisgodmother, a maiden aunt, who had in her earlier days had a disappointment. Nat had once closely questioned his father as to how he came by his name, and the latter had replied testily:"Well, my boy, your Aunt Eliza, who is, you know, a very good woman—no one can doubt that—had a weakness. I never myself got at the rights of the matter. Anyhow, his name was Nathaniel. I don't think there was ever any formal engagement between them. Her own idea is that he loved her, but that his parents forbade him to think of her; for that was at a time before her Aunt Lydia left all her money to her. Anyhow, he went abroad, and I don't think she ever heard of him again.I am inclined to think it was an entire mistake on her part, and that the young fellow had never had the slightest fancy for her. However, that was the one romance of her life, and she has clung to it like a limpet to a rock. At any rate when we asked her to be your godmother she said she would be so if we would give you the name of Nathaniel. I own it is not a name that I like myself; but when we raised an objection, she said that the name was very dear to her, and that if you took it she would certainly make you her heir, and more than hinted that if you had any other name she would leave her money to charitable purposes. Well, you see, as she is worth thirty thousand pounds if she is worth a penny, your mother and I both thought it would be folly to allow the money to go out of the family for the sake of a name, which after all is not such a bad name.""I think it beastly, father, in the first place because it is long.""Well, my boy, if you like we can shorten it to Nathan.""Oh, that would be a hundred times worse! Nathan[Pg 3] indeed! Nat is not so bad. If I had been christened Nat I should not have particularly minded it. Why did you not propose that to aunt?"His father shook his head. "That would never have done. To her he was always Nathaniel. Possibly if they had been married it might some day have become Nat, but, you see, it never got to that.""Well, of course, father," the boy said with a sigh, "as the thing is done it cannot be helped. And I don't say that aunt isn't a good sort—first-rate in some things, for she has always tipped me well whenever she came here, and she says she is going to allow me fifty pounds a year directly I get my appointment as midshipman; but it is certainly hard on me that she could not have fallen in love with some man with a decent name. Nathaniel is always getting me into rows. Why, the first two or three years I went to school I should say that I had a fight over it once a month. Of course I have not had one lately, for since I licked Smith major fellows are more careful. I expect it will be just as bad in the navy."So when he first joined Nat had found it, but now that he was nearly sixteen, and very strong and active, and with the experience of many past combats, the name Nathaniel had been dropped. It was six months since the obnoxious Christian name had been used, as it was now by a young fellow of seventeen who had been transferred to the Orpheus when the frigate to which he belonged was ordered home. He was tall and lanky, very particular about his dress, spoke in a drawling supercilious way, and had the knack of saying unpleasant things with an air of innocence.Supposing that Glover's name must be Nathaniel, he had thought it smart so to address him, but although he guessed that it might irritate him, he was unprepared for an explosion on the part of a lad who was proverbially good-tempered.[Pg 4]"Dear me," he said, in assumed surprise, "I had no idea that you objected so much to be called by your proper name! However, I will, of course, in future use the abbreviation.""You had better call me Glover," Nat replied sharply. "My friends can call me Nat, but to other people I am Glover, and if you call me out of that name there will be squalls; so I warn you."Curtis thought it was well not to pursue the subject further. He was no coward, but he had the sense to see that as Nat was a favourite with the others, while he was a new-comer, a fight, even if he were the victor, would not conduce to his popularity among his mess-mates. The president of the mess, a master's mate, a good-tempered fellow, who hated quarrels, broke what would have been an awkward silence by saying:"We seem to be out of luck altogether this trip; we have been out three weeks and not fired a shot. It is especially hard, for we caught sight of that brigantine we have been in search of, and should have had her if she hadn't run into that channel where there was not water enough for us to follow her.""Yes, that was rough upon us, and one hates to go back to Port Royal without a prize, after having taken so many that we have come to be considered the luckiest ship on the station," another said. "Still, the cruise is not over yet. I suppose by the way we are laying our course, Marston, we are going into Cape Fran?ois?"The mate nodded. "Yes; we want fresh meat, fruit, and water, and it is about the pleasantest place among these islands. I have no doubt, too, that the captain hopes to get some news that may help him to find out where those piratical craft that are doing so much mischief have their rendezvous. They are all so fast that unless in a strong breeze a frigate has no chance whatever of overhauling them; there is no doubt that they are all of Spanish build, and in a light breeze they sail[Pg 5] like witches. I believe our only chance of catching them is in finding them at their head-quarters, wherever that may be, or by coming upon them in a calm in a bay. In that case it would be a boat affair; and a pretty sharp one I should think, for they all carry very strong crews and are heavily armed, and as the scoundrels know that they fight with ropes round their necks they would be awkward customers to tackle.""Yes, if we happened to find them all together, I don't think the captain would risk sending in the boats. One at a time we could manage, but with three of them mounting about fifty guns between them, and carrying, I should say, from two hundred to two hundred and fifty men, the odds would be very great, and the loss, even if we captured them, so heavy that I hardly think the captain would be justified in attempting it. I should say that he would be more likely to get out all the boats and tow the frigate into easy range. She would give a good account of the whole of them.""Yes, there is no doubt about that; but even then we should only succeed if the bay was a very narrow one, for otherwise their boats would certainly tow them faster than we could take the frigate along."It was Glover who spoke last."I don't think myself that we shall ever catch them in the frigate. It seems to me that the only chance will be to get hold of an old merchantman, put a strong crew on board and a dozen of our guns, and cruise about until one of them gets a sight of us and comes skimming along to capture us.""Yes, that would be a good plan; but it has been tried several times with success, and I fancy the pirates would not fall into the trap. Besides, there is very little doubt that they have friends at all these ports, and get early information of any movements of our ships, and would hear of what we were doing long before the disguised ship came near them. It[Pg 6] can hardly be chance, that it matters not which way we cruise these fellows begin their work in another direction altogether. Now that we are here in this great bay, they are probably cruising off the west of Cuba or down by Porto Rico or the Windward Islands. That is the advantage that three or four craft working together have: they are able to keep spies in every port that our ships of war are likely to go into, while a single vessel cannot afford such expenses.""I don't think that the expenses, Low, would be heavy; the negroes would do it for next to nothing, and so would the mulattoes, simply because they hate the whites. I don't mean the best of the mulattoes, because many of them are gentlemen and good fellows; but the lower class are worse than the negroes, they are up to any devilment, and will do anything they can to injure a white man.""Poor beggars, one can hardly blame them; they are neither one thing nor the other! These old French planters are as aristocratic as their noblesse at home, and indeed many of them belong to noble families. Even the meanest white—and they are pretty mean some of them—looks down upon a mulatto, although the latter may have been educated in France and own great plantations. The negroes don't like them because of their strain of white blood. They are treated as if they were pariahs. Their children may not go to school with the whites, they themselves may not sit down in a theatre or kneel at church next to them, they may not use the same restaurants or hotels. No wonder they are discontented.""It is hard on them," Glover said, "but one can't be surprised that the whites do fight shy of them. Great numbers of them are brutes and no mistake, ready for any crime and up to any wickedness. There is lots of good in the niggers; they are merry fellows; and I must say for these old French planters they use their slaves a great deal better[Pg 7] than they are as a rule treated by our planters in Jamaica. Of course there are bad masters everywhere, but if I were a slave I would certainly rather be under a French master than an English one, or, from what I have heard, than an American.""Very well, Glover, I will make a note of that, and if you ever misbehave yourself and we have to sell you, I will drop a line to the first luff how your preference lies."Early the next morning the frigate dropped anchor at Cape Fran?ois, the largest and most important town in the island, with the exception of the capital of the Spanish portion of San Domingo. The Orpheus carried six midshipmen. Four of these had been ashore when on the previous occasion the Orpheus had entered the port. Nat Glover and Curtis were the exceptions, Curtis having at that time belonged to the frigate for but a very few weeks, and Nat having been in the first lieutenant's bad books, owing to a scrape into which he had got at the last port they had touched at. After breakfast they went up together to the first lieutenant, whose name was Hill."Please, sir, if we are not wanted, can we have leave for the day?"The lieutenant hesitated, and then said:"Yes, I think the other four will be enough for the boats. You did not go ashore last time you were here, I think, Mr. Glover," he added with a slight smile."No, sir.""Very well, then, you can go, but don't get into any scrape.""I will try not to, sir," Nat said demurely."Well, I hope your trial will be successful, Mr. Glover, for if not, I can tell you that it will be a long time before you have leave again. These people don't understand that sort of thing.""He is a nice lad," Mr. Hill said to the second lieutenant[Pg 8] as the two midshipmen walked away, "and when he has worked off those animal spirits of his he will make a capital officer, but at present he is one of the most mischievous young monkeys I ever came across.""He does not let them interfere with his duty," the other said. "He is the smartest of our mids; he is well up in navigation, and has any amount of pluck. You remember how he jumped overboard in Port Royal when a marine fell into the water, although the harbour was swarming with sharks. It was a near touch. Luckily we threw a bowline to him, and the two were hauled up together. A few seconds more and it would have been too late, for there was a shark within twenty feet of them.""Yes, there is no doubt about his pluck, Playford, and indeed I partly owe my life to him. When we captured that piratical brigantine near Santa Lucia I boarded by the stern, and she had such a strong crew that we were being beaten back, and things looked very bad until he with the gig's crew swarmed in over the bow. Even then it was a very tough struggle till they cut their waythrough the pirates and joined us, and we went at them together, and that youngster fought like a young fiend. He was in the thick of it everywhere, and yet he was as cool as a cucumber. Oh yes, he has the making of a very fine officer. Although I am obliged to be sharp with him, there is not a shadow of harm in the lad, but he certainly has a genius for getting into scrapes."The two midshipmen went ashore together. "I don't know what you are going to do, Curtis, but after I have walked through the place and had a look at it, I shall hire a horse and ride out into the country.""It is too hot for riding," the other said. "Of course I shall see what there is to be seen, and then I shall look for a seat in some place in the shade and eat fruit."[Pg 9]"Well, we may as well walk through the town together," Nat said cheerfully. "From the look of the place I should fancy there was not much in it, and I know the fellows who went on shore before said that the town contained nothing but native huts, a few churches, and two or three dozen old French houses."Half an hour indeed sufficed to explore the place. When they separated Nat had no difficulty in hiring a horse. He had been accustomed, when in England, to ride a pony, and was therefore at home in the saddle; he proceeded at a leisurely pace along the road across the flat plain that surrounded Cape Fran?ois. On either side were plantations,—sugar-cane and tobacco,—and he occasionally passed the abode of some wealthy planter, surrounded by shady trees and gardens gorgeous with tropical plants and flowers. He was going by one of these, half a mile from the town, when he heard a loud scream, raised evidently by a woman in extreme pain or terror. He was just opposite the entrance, and, springing from his horse, he ran in.On the ground, twenty yards from the gate, lay a girl. A huge hound had hold of her shoulder, and was shaking her violently. Nat drew his dirk and gave a loud shout as he rushed forward. The hound loosed his hold of the girl and turned to meet him, and, springing upon him with a savage growl, threw him to the ground. Nat drove his dirk into the animal as he fell, and threw his left arm across his throat to prevent the dog seizing him there. A moment later the hound had seized it with a grip that extracted a shout of pain from the midshipman. As he again buried his dirk in the hound's side, the dog shifted his hold from Nat's forearm to his shoulder and shook him as if he had been a child.Nat made no effort to free himself, for he knew that were he to uncover his throat for a moment the dog would[Pg 10] seize him there. Though the pain was terrible he continued to deal stroke after stroke to the dog. One of these blows must have reached the heart, for suddenly its hold relaxed and it rolled over, just as half a dozen negroes armed with sticks came rushing out of the house. Nat tried to raise himself on his right arm, but the pain of the left was so great that he leant back again half-fainting. Presently he felt himself being lifted up and carried along; he heard a lady's voice giving directions, and then for a time he knew no more. When he came to himself he saw the ship's doctor leaning over him."What is the matter, doctor?" he asked."You are badly hurt, lad, and must lie perfectly quiet. Luckily the messenger who was sent to fetch a doctor, seeing Mr. Curtis and me walking up the street, ran up to us and said that a young officer of our ship was hurt, and that he was sent in to fetch a doctor. He had, in fact, already seen one, and was in the act of returning with him when he met us. Of course I introduced myself to the French doctor as we came along together, for we fortunately got hold of a trap directly, so that no time was lost. The black boy who brought the message told me that you and a young lady had been bitten by a great hound belonging to his master, and that you had killed it. Now, my lad, I am going to cut off your coat and look at your wounds. The Frenchman is attending to the young lady.""Mind how you touch my arm, doctor! it is broken somewhere between the elbow and the wrist;I heard it snap when the brute seized me. It threw me down, and I put my arm across over my throat, so as to prevent it from getting at that. It would have been all up with me if it had gripped me there.""That it would, Glover. I saw the dog lying on the grass[Pg 11] as I came in. It is a big bloodhound; and your presence of mind undoubtedly saved your life."By this time he had cut the jacket and shirt up to the neck. Nat saw his lips tighten as he caught sight of the wound on the shoulder."It is a bad bite, eh, doctor?""Yes, it has mangled the flesh badly. The dog seems to have shifted his hold several times.""Yes, doctor, each time I stabbed him he gave a sort of start, and then caught hold again and shook me furiously. After the first bite I did not seem to feel any pain. I suppose the limb was numbed.""Very likely, lad. Now I must first of all see what damage was done to the forearm. I am afraid I shall hurt you, but I will be as gentle as I can."Nat clenched his teeth and pressed his lips tightly together. Not a sound was heard as the examination was being made, although the sweat that started out on his forehead showed how intense was the pain."Both bones are broken," the surgeon said to his French colleague, who had just entered the room and came up to the bedside. "The first thing to do is to extemporize some splints, and of course we shall want some stuff for bandages.""I will get them made at once," the doctor replied. "Madame Demaine said that she put the whole house at my disposal."He went out, and in a few minutes returned with some thin slips of wood eighteen inches long and a number of strips of sheeting sewn together."It is very fortunate," the surgeon said, "that the ends of the bone have kept pretty fairly in their places instead of working through the flesh, which they might very well have done.[Pg 12]"Very carefully the two surgeons bandaged the arm from the elbow to the finger-tips."Now for the shoulder," the doctor said.They first sponged the wounds and then began feeling the bones again, giving exquisite pain to Nat. Then they drew apart and consulted for two or three minutes."This is a much worse business than the other," Dr. Bemish said when he returned to the bedside; "the arm is broken near the shoulder, the collar-bone is broken too, and the flesh is almost in a pulp.""Don't say I must lose the arm, doctor," Nat said."Well, I hope not, Glover, but I can't say for certain. You see I am speaking frankly to you, for I know that you have pluck. The injury to the collar-bone is not in itself serious, but the other is a comminuted fracture.""What is comminuted, doctor?""It means that the bone is splintered, lad. Still, there is no reason why it should not heal again; you have a strong constitution, and Nature works wonders."For the next half-hour the two surgeons were at work picking out the fragments of bone, getting the ends together, and bandaging the arm and shoulder. Nat fainted under the pain within the first few minutes, and did not recover until the surgeons had completed their work. Then his lips were wetted with brandy and a few drops of brandy and water were poured down his throat. In a minute or two he opened his eyes."It is all over now, lad." He lay for sometime without speaking, and then whispered, "How is the girl?""Her shoulder is broken," Dr. Bemish replied. "I have not seen her; but the doctor says that it is a comparatively simple case.""How was it the dog came to bite her?"[Pg 13]"She was a stranger to it. She is not the daughter of your hostess. It seems her father's plantationis some twelve miles away; he drove her in and left her here with Madame Demaine, who is his sister, while he went into town on business. Madame's own daughter was away, and the girl sauntered down into the garden, when the hound, not knowing her, sprang upon her, and I have not the least doubt would have killed her had you not arrived.""Are you going to take me on board, doctor?""Not at present, Glover; you need absolute quiet, and if the frigate got into a heavy sea it might undo all our work, and in that case there would be little hope of saving your arm. Madame Demaine told the French doctor that she would nurse you as if you were her own child, and that everything was to be done to make you comfortable. The house is cool, and your wound will have a much better chance of getting well here than in our sick-bay. She wanted to come in to thank you, but I said that, now we had dressed your arm, it was better that you should have nothing to disturb or excite you. When the girl's father returns—and I have no doubt he will do so soon, for as yet, though half-a-dozen boys have been sent down to the town, they have not been able to find him—he must on no account come in to see you at present. Here is a tumbler of fresh lime-juice and water. Doctor Lepel will remain here all night and see that you have everything that you require."The tumbler was held to Nat's lips, and he drained it to the bottom. The drink was iced, and seemed to him the most delicious that he had ever tasted."I shall come ashore again to see you in the morning. Dr. Lepel will go back with me now, and make up a soothing draught for you both. Remember that above all things it is essential for you to lie quiet. He will put bandages round[Pg 14] your body, and fasten the ends to the bedstead so as to prevent you from turning in your sleep.""All right, sir; I can assure you that I have no intention of moving. My arm does not hurt me much now, and I would not set it off aching again for any money.""It is a rum thing," Nat thought to himself, "that I should always be getting into some scrape or other when I go ashore. This is the worst of all by a long way."A negro girl presently came in noiselessly and placed a small table on the right-hand side of the bed. She then brought in a large jug of the same drink that Nat had before taken, and some oranges and limes both peeled and cut up into small pieces."It is lucky it was not the right arm," Nat said to himself. "I suppose one can do without the left pretty well when one gets accustomed to it, though it would be rather awkward going aloft."In an hour Dr. Lepel returned, and gave him the draught."Now try and go to sleep," he said in broken English. "I shall lie down on that sofa, and if you wake up be sure and call me. I am a light sleeper.""Had you not better stay with the young lady?""She will have her mother and her aunt with her, so she will do very well. I hope that you will soon go to sleep."It was but a few minutes before Nat dozed off. Beyond a numbed feeling his arm was not hurting him very much. Once or twice during the night he woke and took a drink. A slight stir in the room aroused him, and to his surprise he found that the sun was already up. The doctor was feeling his pulse, a negro girl was fanning him, and a lady stood at the foot of the bed looking at him pitifully."Do you speak French, monsieur?" she asked."A little," he replied, for he had learned French while at[Pg 15] school, and since the frigate had been among the West Indian islands he had studied it for a couple of hours a day, as it was the language that was spoken in all the French islands and might be useful to him if put in charge of a prize."Have you slept well?" she asked."Very well.""Does your arm hurt you very much now?""It hurts a bit, ma'am, but nothing to make any fuss about.""You must ask for anything that you want," she said. "I have told off two of my negro girls to wait upon you. Of course they both speak French."Half an hour later Dr. Bemish arrived."You are going on very well, Glover," he said after feeling the lad's pulse and putting his hand on his forehead. "At present you have no fever. You cannot expect to get through without some, but I hardly expected to find you so comfortable this morning. The captain told me to say that he would come and see you to-day, and I can assure you that there is not one among your mess-mates who is not deeply sorry at what has happened, although they all feel proud of your pluck in fighting that great hound with nothing but a dirk.""They are useless sort of things, doctor, and I cannot think why they give them to us; but it was a far better weapon yesterday than a sword would have been.""Yes, it was. The room is nice and cool, isn't it?"。

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arXiv:astro-ph/0108394v1 24 Aug 2001
The Central kpc of Starbursts and AGN ASP Conference Series, Vol. xxx, 2001 J. H. Knapen, J. E. Beckman, I. Shlosman, and T. J. Mahoney
A catalogue of AGN observed by the PDS experiment on board BeppoSAX
Matteo Guainazzi XMM-Newton Science Operation Center, VILSPA, ESA, Apartado 50727, E-28080. Madrid, Spain
2Recent BeppoSAX studies (Risaliti et al. 1999) suggest that a sizable fraction of Seyferts are totally thick to Compton-scattering, with NH > 1025 cm−2. In this case the nuclear transmitted ﬂux is strongly suppressed and even the PDS is of very little help.
In this paper we describe the state-of-the-art complete catalogue of Active Galactic Nuclei (AGN) observed by the PDS. Thanks to the last minute extension of the operational life of BeppoSAX, one year beyond the originally foreseen switch-oﬀ (April 2001), this is still a work in progress.
APS Conf. Ser. Style
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Figure 2. Left panel: Radio versus X-ray luminosity for the PDS AGN catalogue. The position of NGC 1052 is marked: it is a LINER, whose X-ray emission is likely to be dominated by an advectiondominated ﬂow (Guainazzi et al. 2000b) Right panel: FIR-to-X-ray luminosity ratios versus the X-ray luminosity for the same sample
1. AGN spectroscopy above 10 keV
The main goal of AGN observations above 10 keV is the direct observation of the nuclear emission of absorbed Seyferts1. Type 2 Seyferts suﬀer signiﬁcant extinction in the X-ray band, mainly due to photoelectric absorption by cold matter. As long as the absorbing column density, NH, is lower then a few
30 keV] against the ratio between the 5 Ghz and the 20-200 keV ﬂuxes, Rrx. For Rrx < 10−3, HR is conﬁned within a narrow band around HR = 0, whereas AGN with a stronger relative radio power tend to suﬀer a substantially higher scatter of the data points, likely to be due to the dichotomy of physical processes (synchrotron and inverse Compton), dominating the blazar emission in this energy band.
The Phoswitch Detector System (PDS; Frontera et al. 1997) - one of the four Narrow Field Instruments on board the Italian-Dutch satellite BeppoSAX (Boella et al. 1997) - is an array of four independent NaI(Tl)/CsI(Na) scintillation detectors. With an hexagonal collimated ﬁeld of view of 1◦. 3, the PDS was designed to ensure moderate resolution spectroscopy (∆E/E ≤ 15% at 60 keV) in the energy range between 13 and 200 keV. The accurate control of the instrumental and celestial background (at the level of one tenth of mCrab) and the unprecedented sensitivity are the most outstanding properties of this instrument, whose performances are likely to remain unsurpassed for many years to come.
In Figure 1 we show the distribution function of the photon spectral indices for several classes of AGN. PDS spectra have been ﬁt with a simple power-law model with high-energy cut-oﬀ (the latter component being required at a conﬁdence level higher than 99% only in 4 objects). The mean of the distributions for type 1 and type 2 Seyferts are virtually indistinguishable: Γ Sy1 = 1.678±0.014 (σSy1 = 0.070), and Γ Sy2 = 1.663 ± 0.013 (σSy2 = 0.069), respectively. For comparison, we show also the distribution for a the sample of radio-loud quasars (radio galaxies and blazars): Γ RG = 1.75 ± 0.04 (σRG = 0.104), and Γ Bl = 1.90 ± 0.03 (σBl = 0.128), respectively. The diﬀerence seems to be related to the skeweness of the distribution around the maximum value. In the right panel of Figure 1 we compare the PDS hardness ratio [deﬁned as HR ≡ (H − S)/(H + S), where S and H are the counts below and above
In this paper we consider all the PDS observations of AGN, whose data were publicly available on March 2001, and which yielded a ≥3σ PDS detection. For the typical exposure time of a BeppoSAX observation (50 ks), this level corresponds to a count rate of about 0.15 s−1, or 1 mCrab.
1024 cm−2, PDS spectra are basically unaﬀected by absorption, and the intrinsic nuclear emission of diﬀerent ﬂavors of AGN can be directly compared2.
The general astrophysical context of this study is the uniﬁcation scenario for Seyfert galaxies (Antonucci 1993). If the observational diﬀerences between absorbed and unabsorbed AGN are indtion of systems, that otherwise share a common nuclear engine, hard X-ray observations should allow us to observe the emission from the innermost region of the active nucleus, overcoming any ”contamination” from the surrounding environment. Any Seyfert type-dependent diﬀerences in the hard X-ray properties would undermine one of the basic assumption of the uniﬁcation scenario.