On the nature of the short duration GRB 050906

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2011年12月六级考试真题

2011年12月大学英语六级考试真题Part I Writing (30 minutes)Directions:For this part, you are allowed 30 minutes to write a short essay entitled The Way to Success by commenting on Abraham Lincoln’s famous remark, “Give me six hours to chop do wn a tree, and I will spend thefirst four sharpening the axe.” You should write at least 150 words but no more than 200 words.The Way to Success__________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ Part II Reading Comprehension (Skimming and Scanning)(15 minutes)Directions: In this part, you will have 15 minutes to go over the passage quickly and answer the questions on Answer Sheet 1. For questions 1–7, choose the best answer from the four choices marked [A], [B], [C] and [D]. For questions 8–10, complete the sentences with the information given in the passage.Google’s Plan for World’s Biggest Online Library: Philanthropy Or Act of Piracy?In recent years, teams of workers dispatched by Google have been working hard to make digital copiesof books. So far, Google has scanned more than 10 million titles from libraries in America and Europe —including half a million volumes held by the Bodleian in Oxford. The exact method it uses is unclear; the company does not allow outsiders to observe the process.Why is Google undertaking such a venture? Why is it even interested in all those out-of-print library books, most of which have been gathering dust on forgotten shelves for decades? The company claims its motives are essentially public-spirited. Its overall mission, after all, is to “organise the world’s information”,so it would be odd if that information did not include books.The company likes to present itself as having lofty aspirations. “This really isn’t about making money.We are doing this for the good of society.” As Santiago de la Mora, head of Google Books for Europe, putsit: “By making it possible to search the millions of books that exist today, we hope to expand the frontiers of human knowledge.”Dan Clancy, the chief architect of Google Books, does seem genuine in his conviction that this is primarily a philanthropic (慈善的) exercise. “Google’s core business is search and find, so obviously what helps improve Google’s search engine is good for Google,” he says. “But we have never built a spreadsheet(电子数据表) outlining the financial benefits of this, and I have never had to justify the amount I am spending to the company’s founders.”It is easy, talking to Clancy and his colleagues, to be swept along by their missionary passion. But Google’s book-scanning project is proving controversial. Several opponents have recently emerged, ranging from rival tech giants such as Microsoft and Amazon to small bodies representing authors and publishers across the world. In broad terms, these opponents have levelled two sets of criticisms at Google.First, they have questioned whether the primary responsibility for digitally archiving the world’s books should be allowed to fall to a commercial company. In a recent essay in the New York Review of Books, Robert Darnton, the head of Harvard University’s library, argued that because such books are a common resource —the possession of us all —only public, not-for-profit bodies should be given the power to control them.The second related criticism is that Google’s scanning of books is actually illegal. This allegation has led to Google becoming mired in (陷入) a legal battle whose scope and complexity makes the Jarndyce and Jarndyce case in Charles Dickens’ Bleak House look straightforward.At its centre, however, is one simple issue: that of copyright. The inconvenient fact about most books, to which Google has arguably paid insufficient attention, is that they are protected by copyright. Copyright laws differ fro m country to country, but in general protection extends for the duration of an author’s life and for a substantial period afterwards, thus allowing the author’s heirs to benefit. (In Britain and America, this post-death period is 70 years.) This means, of course, that almost all of the books published in the 20th century are still under copyright —and the last century saw more books published than in all previous centuries combined. Of the roughly 40 million books in US libraries, for example, an estimated 32 million are in copyright. Of these, some 27 million are out of print.Outside the US, Google has made sure only to scan books that are out of copyright and thus in the “public domain” (works such as the Bodleian’s first edition of Middlemarch, which anyone can read for free on Google Books Search).But, within the US, the company has scanned both in-copyright and out-of-copyright works. In its defence, Google points out that it displays only small segments of books that are in copyright — arguing that s uch displays are “fair use”. But critics allege that by making electronic copies of these books without first seeking the permission of copyright holders, Google has committed piracy.“The key principle of copyright law has always been that works can be co pied only once authors have expressly given their permission,” says Piers Blofeld, of the Sheil Land literary agency in London. “Google has reversed this —it has simply copied all these works without bothering to ask.”In 2005, the Authors Guild of America, together with a group of US publishers, launched a class action suit (集团诉讼) against Google that, after more than two years of negotiation, ended with an announcement last October that Google and the claimants had reached an out-of-court settlement. The full details are complicated —the text alone runs to 385 pages —and trying to summarise it is no easy task. “Part of the problem is that it is basically incomprehensible,” says Blofeld, one of the settlement’s most vocal British critics.Broadly, the deal provides a mechanism for Google to compensate authors and publishers whose rights it has breached (including giving them a share of any future revenue it generates from their works). In exchange for this, the rights holders agree not to sue Google in future.This settlement hands Google the power — but only with the agreement of individual rights holders —to exploit its database of out-of-print books. It can include them in subscription deals sold to libraries or sell them individually under a consumer licence. It is these commercial provisions that are proving the settlement’s most controversial aspect.Critics point out that, by giving Google the right to commercially exploit its database, the settlement paves the way for a subtle shift in the company’s role from provider of information to seller. “Google’s business model has always been to provide information for free, and sell advertising on the basis of the traffic this generates,” points out James Grimmelmann, associate professor at New York Law Scho ol. Now, he says, because of the settlement’s provisions, Google could become a significant force in bookselling.Interest in this aspect of the settlement has focused on “orphan” works, where there is no known copyright holder —these make up an estimated 5-10% of the books Google has scanned. Under the settlement, when no rights holders come forward and register their interest in a work, commercial control automatically reverts to Google. Google will be able to display up to 20% of orphan works for free, include them in its subscription deals to libraries and sell them to individual buyers under the consumer licence.It is by no means certain that the settlement will be enacted (执行) — it is the subject of a fairness hearing in the US courts. But if it is enacted, Google will in effect be off the hook as far as copyright violations in the US are concerned. Many people are seriously concerned by this —and the company is likely to face challenges in other courts around the world.No one knows the precise use Google will make of the intellectual property it has gained by scanning the world’s library books, and the truth, as Gleick, an American science writer and member of the Authors Guild, points out, is that the company probably doesn’t even know itself. But what is certain is that, in some way or other, Google’s entrance into digital bookselling will have a significant impact on the book world in the years to come.1. Google claims its plan for the world’s biggest online library is _______.[A] to save out-of-print books in libraries [B] to encourage reading around the world[C] to promote its core business of searching [D] to serve the interest of the general public2. According to Santiago de la Mora, Google’s book-scanning project will _______.[A] make full use of the power of its search engine [B] help the broad masses of readers[C] revolutionise the entire book industry [D] broaden humanity’s intellectual horizons3. Opponents of Google Books believe that digitally archiving the world’s books should be controlled by_______.[A] non-profit organisations [B] the world’s tech giants[C] multinational companies [D] the world’s leading libraries4. Google has involved itself in a legal battle as it ignored _______.[A] the copyright of the books it scanned[B] the interest of traditional booksellers[C] the differences of in-print and out-of-print books[D] the copyright of authors of out-of-print books5. Google defends its scanning in-copyright books by saying that _______.[A] making electronic copies of books is not a violation of copyright[B] it displays only a small part of their content[C] it is willing to compensate the copyright holders[D] the online display of in-copyright books is not for commercial use6. What do we learn about the class action suit against Google?[A] It ended in a victory for the Authors Guild of America.[B] It could lead to more out-of-court settlements of such disputes.[C] It failed to protect the interests of American publishers.[D] It was settled after more than two years of negotiation.7. What remained controversial after the class action suit ended?[A] The change in Google’s business model.[B] The compensation for copyright holders.[C] The commercial provisions of the settlement. [D] Google’s further exploit ation of its database.8. While _______________________________, Google makes money by selling advertising.9. Books whose copyright holders are not known are called _______________________________.10. Google’s entrance into digital bookselling will treme ndously _______________________________ in thefuture.Part III Listening Comprehension (35 minutes)Section ADirections: In this section, you will hear 8 short conversations and 2 long conversations. At the end of each conversation, one or more questions will be asked about what was said. Both the conversation and the questions will be spoken only once. After each question there will be a pause. During the pause, you must read the four choices marked [A], [B], [C] and [D], and decide which is the best answer. Then mark the corresponding letter on Answer Sheet 2 with a single line through the centre.11. [A] Listen to the recorded notes while driving. [B] Cancel the trip to prepare for the test.[C] Prepare for the test after the wedding. [D] Review his notes once he arrives in Chicago.12. [A] The woman will help the man remember the lines.[B] The woman will prompt the man during the show.[C] The man lacks confidence in playing the part.[D] The man hopes to change his role in the play.13. [A] Arranging a bed for a patient. [B] Rescuing the woman’s uncle.[C] A complicated surgical case. [D] Preparations for an operation.14. [A] He is too busy to accept more responsibility. [B] He is interested in improving his editing skills.[C] He is eager to be nominated the new editor. [D] He is sure to do a better job than Simon.15. [A] He has been successfully elected Prime Minister.[B] He has already reached the retirement age.[C] He has left his position in the government. [D] He made a stupid decision at the cabinet meeting.16. [A] This year’s shuttle mission is a big step in space exploration.[B] The shuttle flight will be broadcast live worldwide.[C] The man is excited at the news of the shuttle flight.[D] The man is well informed about the space shuttle missions.17. [A] At an auto rescue center. [B] At a car renting company.[C] At a mountain camp. [D] At a suburban garage.18. [A] He listened to some serious music. [B] He bought a stereo system.[C] He got his speakers fixed. [D] He went shopping with the woman.Questions 19 to 21 are based on the conversation you have just heard.19. [A] Providing aid to the disabled. [B] Selling products made for left-handers.[C] Promoting products for manufacturers. [D] Printing labels for manufactured goods.20. [A] About half of them are unavailable on the market.[B] The kitchenware in his shop is of unique design.[C] All of them are manufactured in his own plant.[D] Most of them are specially made for his shop.21. [A] They specialise in one product only. [B] They have outlets throughout Britain.[C] They run chain stores in central London. [D] They sell by mail order only.Questions 22 to 25 are based on the conversation you have just heard.22. [A] It publishes magazines. [B] It is engaged in product design.[C] It sponsors trade fairs. [D] It runs sales promotion campaigns.23. [A] The woman’s company failed to make payments in time.[B] The ad specifications had not been given in detail.[C] The woman’s company made last-minute changes.[D] Organising the promotion was really time-consuming.24. [A] Run another four-week campaign. [B] Give her a 10 percent discount.[C] Extend the campaign to next year. [D] Cut the fee by half for this year.25. [A] Calm down and make peace. [B] Improve their promotion plans.[C] Stop negotiating for the time being. [D] Reflect on their respective mistakes.Section BDirections: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked [A], [B], [C] and [D]. Then mark the corresponding letter on Answer Sheet 2 with a single line through the centre.Passage OneQuestions 26 to 29 are based on the passage you have just heard.26. [A] They are looked after by animal-care organizations.[B] They sacrifice their lives for the benefit of humans.[C] They look spotlessly clean throughout their lives.[D] They are labeled pet animals by the researchers.27. [A] They may breed out of control. [B] They may cause damage to the environment.[C] They may behave abnormally. [D] They may affect the results of experiments.28. [A] When they are no longer useful. [B] When they become ill.[C] When they become escapees. [D] When they get too old.29. [A] While calling for animal rights, they allowed their kids to keep pet animals.[B] While holding a burial ceremony for a pet mouse, they were killing pest mice.[C] While launching animal protection campaigns, they were trapping kitchen mice.[D] While advocating freedom for animals, they kept their pet mouse in a cage.Passage TwoQuestions 30 to 32 are based on the passage you have just heard.30. [A] They contribute most to it. [B] They often find fault with it.[C] They take it for granted. [D] They are crazy about it.31. [A] Tidal restlessness. [B] Historical continuity.[C] Heat and light. [D] Economic prosperity.32. [A] They are adventurers from all over the world. [B] They lack knowledge of the culture of the city.[C] They find the city alien to them. [D] They have difficulty surviving.Passage ThreeQuestions 33 to 35 are based on the passage you have just heard.33. [A] A murder mystery. [B] A football game.[C] A political debate. [D] A documentary.34. [A] It help s broaden one’s horizons.[B] It enhances family relationships.[C] It is a sheer waste of time. [D] It is unhealthy for the viewers.35. [A] He watches T.V. programs only selectively. [B] He doesn’t like watching sports programs.[C] He c an’t resist the temptation of T.V. either. [D] He is not a man who can keep his promise. Section CDirections: In this section, you will hear a passage three times. When the passage is read for the first time, you should listen carefully for its general idea. When the passage is read for the second time, you are required to fill in the blanks numbered from 36 to 43 with the exact words you have just heard. For blanks numbered from 44 to 46 you are required to fill in the missing information. For these blanks, you can either use the exact words you have just heard or write down the main points in your own words. Finally, when the passage is read for the third time, you should check what you have written.In the past, one of the biggest disadvantages of machines has been their inability to work on a micro-scale. For example, doctors did not have devices allowing them to go inside the human body to (36) ________ health problems or to perform (37) ________ surgery. Repair crews did not have a way of (38) ________ broken pipes located deep within a high-rise (39) ________ building. However, that’s about to change. Advances in computers and biophysics have started a microminiature(超微) (40) ________ that allows scientists to envision — and in some cases actually build — microscopic machines. These devices promise to (41) ________ change the way we live and work.Micromachines already are making an impact. At Case Western Reserve University in Cleveland, Ohio, research scientists have designed a 4-inch silicon chip that holds 700 tiny (42) ________ motors. At Lucas NovaSensor in Fremont, California, scientists have perfected the world’s first microscopic blood-pressure sensor. Threaded through a person’s blood (43) ________, the sensor can provide blood pressure readi ngs at the valve of the heart itself.(44) ______________________________________________________________________. Auto manufacturers, for example, are trying to use tiny devices (45)______________________________________________________________. Some futurists envision nanotechnology (纳米技术) also being used to explore the deep sea in small submarines, or even to launch finger-sized rockets packed with microminiature instruments.There is an explosion of new ideas and applications. So, (46)______________________________________________________________________.Part IV Reading Comprehension (Reading in Depth) (25 minutes)Section ADirections: In this section, there is a short passage with 5 questions or incomplete statements. Read the passage carefully. Then answer the questions or complete the statements in the fewest possible words. Please write your answers on Answer Sheet 2.Questions 47 to 51 are based on the following passage.Leadership is the most significant word in today’s competitive busines s environment because it directs the manager of a business to focus inward on their personal capabilities and style. Experts on leadership will quickly point out that “how things get done” influences the success of the outcomes and indicates a right way and a wrong way to do things. When a noted leader on the art of management, Peter Drucker, coined the phrase “Management is doing things right; leadership is doing the right things,” he was seeking to clarify the distinctions he associates with the terms.When Stephen Covey, founder and director of the Leadership Institute, explored leadership styles in the past decade, he focused on the habits of a great number of highly effective individuals. His Seven Habits of Highly Effective People became a popular bestseller very quickly. His ideas forced a reexamination of the early leadership paradigm(范例), which he observed centered on traits found in the character ethic and the personality ethic. The former ethic suggested success was founded on integrity, modesty, loyalty, courage, patience, and so forth. The personality ethic suggested it was one’s attitude, not behavior, that inspired success, and this ethic was founded on a belief of positive mental attitude. In contrast to each of these ideas, Covey advocates that leaders need to understand universal principles of effectiveness, and he highlights how vital it is for leaders to first personally manage themselves if they are to enjoy any hope of outstanding success in their work environments. To achieve a desired vision for your business, it is vital that you have a personal vision of where you are headed and what you value. Business leadership means that managers need to “put first things first,” which implies that before leading others, you need to be clear on you r own values, abilities, and strengths and be seen as trustworthy.47. To be good leaders, managers must pay close attention to their own _____________________.48. According to Peter Drucker, leaders should be good at _____________________.49. The personality ethic suggests that people are likely to succeed if they have _____________________.50. According to Stephen Covey, leaders who hope to achieve outstanding success need first of all to_____________________.51. Good leadership requires one to know one’s own strengths and be able to win people’s_____________________.Section BDirections: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked [A], [B], [C] and [D]. You should decide on the best choice and mark the corresponding letter on Answer Sheet 2 with a single line through the centre.Passage OneQuestions 52 to 56 are based on the following passage.What’s the one word of advice a well-meaning professional would give to a recent college graduate? China? India? Brazil? How about trade?When the Commerce Department reported last week that the trade deficit in June approached $50 billion, it set off a new round of economic doomsaying. Imports, which soared to $200.3 billion in the month, are subtracted in the calculation of gross domestic product. The larger the trade deficit, the smaller the GDP. Should such imbalances continue, pessimists say, they could contribute to slower growth.But there’s anot her way of looking at the trade data. Over the past two years, the figures on imports and exports seem not to signal a double-dip recession — a renewed decline in the broad level of economic activity in the United States — but an economic expansion.The rising volume of trade — more goods and services shuttling in and out of the United States — is good news for many sectors. Companies engaged in shipping, trucking, rail freight, delivery, and logistics (物流) have all been reporting better than expected results. The rising numbers signify growing vitality in foreign markets — when we import more stuff, it puts more cash in the hands of people around the world, and U.S. exports are rising because more foreigners have the ability to buy the things we produce and market. The rising tide of trade is also good news for people who work in trade-sensitive businesses, especially those that produce commodities for which global demand sets the price — agricultural goods, mining, metals, oil.And while exports always seem to lag, U.S. companies are becoming more involved in the global economy with each passing month. General Motors sells as many cars in China as in America each month. While that may not do much for imports, it does help GM’s balance sheet — and hence makes the jobs of U.S.-based executives more stable.One great challenge for the U.S. economy is slack domestic consumer demand. Americans are paying down debt, saving more, and spending more carefully. That’s to be expected, given what we’ve been through. But there’s a bigger challenge. Can U.S.-based businesses, large and small, figure out how to get a piece of growing global demand? Unless you want to pick up and move to India, or Brazil, or China, the best way to do that is through trade. It may seem obvious, but it’s no longer enough simply to do business with our friends and neighbors here at home.Companies and individuals who don’t have a strategy to export more, or to get more involved in foreign markets, or to play a role in global trade, are shutting t hemselves out of the lion’s share of economic opportunity in our world.52. How do pessimists interpret the U.S. trade deficit in June?[A] It could lead to slower growth of the national economy.[B] It reflects Americans’ preference for imported goods.[C] It signifies a change in American economic structure.[D] It is the result of America’s growing focus on domestic market.53. What does the author say about the trade data of the past two years?[A] It indicates that economic activities in the U.S. have increased.[B] It reflects the fluctuations in the international market.[C] It shows that U.S. economy is slipping further into recession.[D] It signals decreasing domestic demand for goods and services.54. Who particularly benefit from the rising volume of trade?[A] People who have expertise in international trade.[B] Producers of agricultural goods and raw materials.[C] Consumers who favor imported goods and services.[D] Retailers dealing in foreign goods and services.55. What is one of the challenges facing the American economy?[A] Decreasing productivity. [B] People’s reluctance to spend.[C] Competition from overseas. [D] Slack trade activities.56. What is the author’s advice to U.S. companies and individuals?[A] To import more cheap goods from developing countries.[B] To be alert to fluctuations in foreign markets.[C] To increase their market share overseas.[D] To move their companies to where labor is cheaper.Passage TwoQuestions 57 to 61 are based on the following passage.A recurr ing criticism of the UK’s university sector is its perceived weakness in translating newknowledge into new products and services.Recently, the UK National Stem Cell Network warned the UK could lose its place among the world leaders in stem cell research unless adequate funding and legislation could be assured. We should take this concern seriously as universities are key in the national innovation system.However, we do have to challenge the unthinking complaint that the sector does not do enough in taking ideas to market. The most recent comparative data on the performance of universities and research institutions in Australia, Canada, USA and UK shows that, from a relatively weak starting position, the UK now leads on many indicators of commercialisation activity.When viewed at the national level, the policy interventions of the past decade have helped transform the performance of UK universities. Evidence suggests the UK’s position is much stronger than in the recent past and is still showing improvement. But national data masks the very large variation in the performance of individual universities. The evidence shows that a large number of universities have fallen off the back of the pack, a few perform strongly and the rest chase the leaders.This type of uneven distribution is not peculiar to the UK and is mirrored across other economies. In the UK, research is concentrated: less than 25% of universities receive 75% of the research funding. These same universities are also the institutions producing the greatest share of PhD graduates, science citations, patents and licence income. The effect of policies generating long-term resource concentration has also created a distinctive set of universities which are research-led and commercially active. It seems clear that the concentration of research and commercialisation work creates differences between universities.The core objective for universities which are research-led must be to maximise the impact of their research efforts. These universities should be generating the widest range of social, economic and environmental benefits. In return for the scale of investment, they should share their expertise in order to build greater confidence in the sector.Part of the economic recovery of the UK will be driven by the next generation of research commercialisation spilling out of our universities. There are three dozen universities in the UK which are actively engaged in advanced research training and commercialisation work.If there was a greater coordination of technology transfer offices within regions and a simultaneous investment in the scale and functions of our graduate schools, universities could, and should, play a key role in positioning the UK for the next growth cycle.57. What does the author think of UK universities in terms of commercialisation?[A] They have lost their leading position in many ways.[B] They fail to convert knowledge into money.[C] They do not regard it as their responsibility.[D] They still have a place among the world leaders.58. What does the author say about the national data on UK universities’ performance in commercialisation?[A] It does not rank UK universities in a scientific way.[B] It does not reflect the differences among universities.[C] It indicates their ineffective use of government resources.[D] It masks the fatal weaknesses of government policy.59. We can infer from Paragraph 5 that “policy interventions” (Line 1. Para. 4) refers to ______.[A] concentration of resources in a limited number of universities[B] government aid to non-research-oriented universities[C] compulsory cooperation between universities and industries[D] fair distribution of funding for universities and research institutions。

航运术语

英文术语英文全称中文解释aaaa always afloat 始终保持漂浮asf as following 依下列各项a/c acct account=charterer 账户acol after completion of loading 装货完毕后a/e accept/ecept 同意afmt after fixing main terms 固定主要条款之后air draft 水上高度a/o and ora/o and/or 和/或a/p additional premium 附加保险费aps on arrival pilot station 到达引航站a/r all risks 全险a/s account sale 销货账a/s after sight 远期付款aa always afloat 永远漂浮aa awiwl always afloat always aitnininstitute warranty limits保持漂浮在协会保证航行范围aar against all risks 针对所有风险abashirl abashirl 纲走aboshi aboshi 纲星abv above 上文abs american bureau of shipping 美国船级社abt aboutabt about 大约acc acceptance/accepted 接受accdg according to 根据acct accounter chrsacdg according 依据acol after completion of loadingacol after completion of loading 装货结束后add address/additionaladdcom address commission 回扣佣金adv advise 告知afmt after fixing main termsafmt after fixing main terms 固定主要条款之后afsp arrival first sea pilotag（=pg）arabian gulf （persian gulf）agt agent 代理人agts agentsagw all goes well 一切顺利agw/wp all going well/whether permitah antwerp/hamburgahl australian holk ladderahps arrival harbour pilot stationahps arrival harbour pilotstation到达港口引航站aims american institute ofmerchant shipping美国商船航运学会aiol aiol 相生akita akita 秋田all flgs abt/all dtls abtalt alternative 二中择一amagasaki amagasaki 尼崎amelog america logamt amoustamwelsh c/pore-americanized welshcoal charteranan anan 阿南anch anchorage 锚地ans answer 回答antham antwerp-hamburgaob as on boardaoh after office houraoh after office hours 工作时间外aomori aomori 青森ap additional premiumap all purposeap 装卸共用时间（锚位）ap additional premium 附加保险费aps arr pilot stationaps arrival pilot stationaps arrival pilot station 到达引航站ara amsterdam/rotterdam/antwerp rgearb y/a 1974 arbitration york antwerp rulearnd aroundarngd arrange 安排arr arrive 到达as explained on telasap as soon as possible 尽可能快地asba association of shipbrokersand agents， inc。

速度向量成像技术VVI临床应用研究进展

目前常用的心脏扭转指标
扭转率
Torsion
（单位距离内的扭转角度 /cm）
Rotation 心底自旋
扭转（ Twist）心尖与心底之间角度差
Rotation (心尖自旋）
心脏扭转运动的研究
• 我们应用Sequoia 512超声诊断仪，以 VVI技术观察了32名健康志愿者的左室扭转运动。结果发现32名健康志愿者: 左室扭转角度为6.10±2.93°，男性左室扭转角度为5.45±2.46°，女性左室扭转角度为7.04±3.31°，男女之间差异无统计学意义（P＞0.05）。
• 动脉粥样硬化斑块血管VVI特点：粥样斑块处运动速度、应变及应变率比无斑块处低；斑块基底部应变率比斑块表面低；动脉粥样硬化血管各壁存在运动不协调，斑块处达峰时间提前。
黄品同等以VVI技术对颈动脉运动特性的检测
正常颈动脉
有粥样斑块的颈动脉
胎儿心脏
• 该技术使胎儿心律失常的评价变得容易，其解剖M型可解决进行胎儿应变率成像时无法获取胎儿心电信号问题。对心律失常时心肌结构力学的变化、心功能等提供精确指标。
新近推出速度向量成像技术（Velocity Vector Imaging，VVI）
可用于：
研究心肌结构力学、分析节段心肌功能的新技术，
为测量心脏扭转运动、应变及应变率、心脏再同步化的评价提供了新的方法，使人们从一个新的视野重新认识心脏运动。
一、基本原理
VVI技术利用超声像素的空间相干、斑点追
左室扭转分析
左室扭转方向规定从心尖向心底部观察逆时针旋转为正方向，反之为负。我们的结果显示心底与心尖均为正占 34%，均为负占13％，心底正心尖负占 25％，心底负心尖正占28％，

TPO 1-24阅读词汇学生讲义汇总

n.沉淀物；冰雹；坠落；鲁莽
词
emerge
音标
[i'mə:dʒ]
词意
出现
词
Particle
音标
['pɑ:tikl]
词意
颗粒,质点
词
Grain
音标
[ɡrein]
词意
粮食谷粒
词
Pebble
音标
['pebl]
词意
卵石
词
Loose
音标
[lu:s]
词意
宽松的；散漫的，不精确的
词
unconsolidated
音标
词意
遭遇，偶然碰见
词
Permit
音标
[pə'mit]
词意
允许，许可
词
Objectify
音标
[əb'dʒektifai,ɔb-]
词意
使具体化使客观化
词根
Object
词
Anxiety
音标
[æŋ'zaiəti]
词意
焦虑
词
Fiction
音标
['fikʃən]
词意
小说；虚构，编造
词
Instinct
音标
['ɪnstɪŋ(k)t]
薄的；瘦的；稀薄的；微弱的
词
Tropic
音标
['trɔpik]
词意
热带的
词
Cessation
音标
[se'seiʃən]
词意
停止；中止
词
Play a role
音标
音标
[sə'fiʃənt]
词意

航运英语术语一览表

ATSDO
ALL TIME SAVED DISCHARGING ONLY
所有卸货港节省时间
ATSLO
ALL TIME SAVED LOADING ONLY
所有装货港节省时间
Atsuti
Atsuti
渥美
ATT
ATTENTION
注意
AUCT
AUCTION
拍卖
AUSSIE
AUSTRALIA
AUTHO
AUTHORITY
AG（=PG）
ARABIAN GULF （PERSIAN GULF）
AGT
AGENT
代理人
AGTS
AGENTS
AGW
ALL GOES WELL
一切顺利
AGW/WP
ALL GOING WELL/WHETHER PERMIT
AH
ANTWERP/HAMBURG
AHL
AUSTRALIAN HOLK LADDER
装货结束后
ADD
ADDRESS/ADDITIONAL
ADDCOM
ADDRESS COMMISSION
回扣佣金
ADV
ADVISE
告知
AFMT
AFTER FIXING MAIN TERMS
AFMT
AFTER FIXING MAIN TERMS
固定主要条款之后
AFSP
ARRIVAL FIRST SEA PILOT
AUTO
AUTOMOBILE
汽车
AWTS
ALL WORDING TIME SAVED
所有节省的工作时间
AWTSBE
ALL WORKING TIME SAVED BOTH ENDS

一些英文词的标准缩写

Budgetable Budget Balance Account Build Building Business Business Unit* Buy Buyer Calculate Calculated Calculation* Calendar* Call Campaign Campus Cancel Canceled Capacity Capitalization Card Career Carrier Cartridge Case Cash Catalog Category* Census Center Certificate Certification Change Changed Chapter Charge Chartfield Check Checked Citizen Citizenship City Class Clear Cleared CLEP Close Club COBRA* Code* Collect Collection College Column Combination Combine Command Comment Committee Company* Comparative* Competitor Complete Completion Compliance Component Composite Compensation Conditional Confidential Confirm
ALPH ALT ALMN AM ACT AMT* ANLS ANNL* ANON ANS APT APEL APP* APPL* APPT APRV AREA ARAY ARRS ASC ASGN ASSC ASMP ATHL ATCH ATMPT ATND ATTN ATTR ADT AUTH AUX AVL AVG ACG AWRD BAL* BNK BARG BAS BTCH BEF BEGN BOT BEN BID BILL BRS BRTH BRD BRK BUD The net value (balance) of an account The mean of two or more numbers Monetary value(s) "Ante Meridiem" (morning)

HCDP英文版最新版多选题

多选题1.Which of the following are characteristics of a high availability network?A Faults seldom occur.B Services can be quickly restored when a fault occurs.C Faults never occur.D Services can only be manually restored when a fault occurs.AB2.Which of the following statements about BFD control packets are true?A BFD control packet is encapsulated in a UDP packet for transmission.B BFD detection is not available in VRP 5.7C Echo packets use UDP destination port number 3784.D Echo packets use UDP destination port number 3785.ABC3.Which of the following statements about the BFD asynchronous mode are true?A The local system regularly send BFD control packets,and the remote system detects theBFD control packets sent from the local system.B The local system detects the BFD control packets sent by itself.C If one system does not receive any BFD packets from its peer within a detection period,itadvertises a session down event.D Each system confirms its connections with other systems in a particular method.After aBFD seeion is set up, BFD control packets are no longer sent .AC4.Which of the following statements about the BFD demand mode are true?A The local system regularly send BFD control packets,and the remote system detects theBFD control packets sent from the local systemB The local system detects the BFD control packets sent by itself.C If one system does not receive any BFD packets from its peer within a detection period,itadvertises a session down event.D Each system confirms its connections with other systems in a particular method.After aBFD seeion is set up, BFD control packets are no longer sent .BD5.Which of the following statements about the BFD echo function are true?A The local system sends a series of BFD Echo packets,and the remote system loops thepackets back through its forwarding channel.B If the local system does not receive several consecutive Echo packets,it advertises asession down event.C The echo function can work together with the asynchronous or demand detection mode.D The echo function can take the place of fault detection by sending BFD control packets. ABCD6.Which of the following statements about a smart link group are true?A Smart link group consists of a maximum of two interfaces,where there are twointerfaces,one is an active interface,and the other a standby interface.B Of the two interface in a smart link group,one is active,and the other is standby.C when an active interface goes down,the Smart link group automatically blocks it andchanges the status of the standby interface to active.D when an active interface recovers,the standby interface is blocked and traffic is switchedback to the active interface.ABC7.Which of the following statements about Flush packets in a smart link group are true?A A smart link group sends flush packets to instruct other devices to update the addresstable.B Flush packets use IEEE 802.3 encapsulation.C The destination MAC address of Fulsh packets is an unknown unicast address,which isused to distinguish protocols.D The destination MAC address of flush packets is a special multicast address,which is usedto distinguish protocols.ABC8.When links are switched in a smart link group, which of the following mechanisms can beused to refresh MAC and ARP entries?A MAC and ARP entries are refreshed automatically with respect to traffic.B The smart link group uses a new link to send flush packets.C MAC entries are refreshed after the aging time expires.D ARP entries are refreshed after the aging time expires.ABC9.Which of the following statements about link aggregation are true?A link aggregation binds a group of physical interfaces together as a logical interface toincrease the bandwidth and reliability.B Link aggregation complies with IEEE 802.3ah.C The logical link formed by bundling multiple physical links together is called a linkaggregation group (LAG) or a trunk.D Active and inactive interfaces exist in link aggregation,Active interfaces forward data,whereas inactive interfaces do not.ABCD10.Which of the following statements about link aggregation are true?A Link aggregation can be performed in manual load balancing or LACP mode.in manualloading balancing mode,LACP is disabled:in LACP mode,LACP is enabled.B In manual load balancing mode,all active member interfaces forward data and performload balancing.C In static LACP mode,the creation of the Eth-Trunk and the addition of member interfacesto the Eth-Trunk are perfaormed pared with link aggregation in manual load balancing mode,active interfaces in static LACP mode are seleted by sending LACP data units(LACPDUs).D Indynamic LACP mode,the creation of the Eth-Trunk,the addition of memberinterfaces,and the selection of active interfaces are performed based on LACP negotiation. ABCD11.Which of the following statements about LACP are true?A It complies with IEEE 802.3ad.B A device enabled with LACP exchanges link Aggregation Control protocol data Units(LACPDUs) with its peer.C Devices at both ends determine the active interface according to the interface priority ofthe active device.ABC12.Which of the following reliability designs are related to routers?A Reliability design of the system and hardwareB Reliability design of the softwareC Reliability test authenticationD Reliability design of the IP networkABCD13.Which of the following can speed up OSPF fast convergence?A Configuring dynamic BFD for OSPFB Adjusting the interval at which OSPF calculation is performedC Configuring the interval at which an LSA are retransmittedD Configuring the maximum number of external LSAs in the LSDBAB14.Which of the following statements about the reliability requirement level are true?A Faults seldom occur in the system software or hardware.B System functions are not affected by faults.C System functions are affected by faults but can rapidly recover.D System functions can be ensured by using redundancy design,switchover policy,and highsuccess rate in switchover.ABCD15.Which of the following are end-to-end link protection modes?A 1:1B M:NC N:1D 1+1ABD16.On a BGP/MPLS IPv4 VPN,OSPF,LDP,and static routes are configured.which of the followingprotocols need to be enabled with GR to achieve NSF on PEs?A OSPFB MPLS LDPC BGPD Static routesABC17.Which of the following statements about BFD are true?A It cannot be used to detect MPLS networks.B It provides low-load and short-duration detection for paths between adjacent forwardingengines.C It provides a unified mechanism for detecting all types of media and BFD-supportingprotocols.D It is a bidirectional detection mechanism.BCD18.Which of the following statements about the setup of a BFD session are true?A A BFD session can be set up in either static or dynamic mode.B A static BFD session is set up by manually configuring BFD session parameters anddelivering requests for setting up a BFD session. BFD session parameters include the local and remote discriminators.C A dynamic BFD session is set up by dynamically allocating local discriminators.D Static and dynamic BFD session are not differentiated.ABC19.Which of the following statements are correct regarding OSPF Router LSA?A Every router running OSPF must generate Router LSA.B In broadcast and NBMA network,only DROther generates Router LSA.C Router LSA describes link states of the router in area.D Router LSA is flooded in the whole AS.AC20.Which of the following statements are correct regarding Network LSA in OSPF network?A Network LSA is generated by ABR.B only the router which connects NBMA or Broadcast Network may generate network LSA.C DR uses network LSA to describe routers that have established adjacency relation with itin the network.D Network LSA is flooded in the whole AS.BC21.Which type of LSA is only used to calculate external route?A Type 1B Type 2C Type 3D Type 4E Type 5DE22.Which of the following are OSPF packet type?A LSAB LS requestC LSPD LS UpdateE LS ackBDE23.Which of the following elements together uniquely identify a LSA?A LS typeB Link state IDC Advertising RouterD LS Sequence numberABC24.Which of the following statements are correct regarding how OSPF detects old and duplicateLSAs?A The smaller the sequence number,the more recent the LSA,B The smaller the LS age,the more recent the LSA.C When router generates a new LSA at the first time,it will use 0x80000001 as thesequence number.D An LSA can be flushed from routing domain by setting its LSA age to Maxage.BCD25.Which of the following statements are correct regarding intra-area route calculation of OSPF?A Every OSPF router only uses one Router LSA to describe local active link state for onearea.B Every OSPF uses more than one Router LSA to describe local active link state for one area.C One Router LSA Only describes one linkD One Router LSA describes more than one linkAD26.In OSPF protocol,which of the following elements are used to describe one link?A Link IDB DataC TypeD MetricABCD27.In OSPF protocol,which of the following elements are used by network LSA to describebroadcast network segment or NBMA network segment?A LINK IDB Net maskC Attached Router listD MetricABC28.Which of the connection types that Router LSA can describe?A Point-to-pointB StubC transitD Virtual linkABCD29.In OSPF, which of the following statements are incorrect regarding Router LSA generated byRouter A?A In point-to-point link type, Data is set to the interface IP address of RouterA.B In TransNet link type,Data is set to the interface IP address of RouterA.C In StubNet link type,Data is set to the interface IP address of RouterA.D In Virtual link type,Data is set to the Router ID of RouterA.CD30.In OSPF protocol,which of the following elements are used by network LSA to describebroadcast network segment or NBMA network segment?A Link IDB Net maskC Attached Router listD MetricABC31.Which of the connection types that Router LSA can describe?A Point-to-pointB StubC TransitD Virtual linkABCD32.In OSPF area,RTA and RTB interconnect through FE interface.which of the followingcommands can be used to configure the link cost between RTA and RTB as 10?A Use commed ospf cost 10 on two routersB Use commed ospf cost 5 on two routersC Use commed bandwidth-reference 500 on two routers to change bandwidth-referencevalueD use command bandwidth-reference 1000 on two routers to change bandwidth-reference AD33.In OSPF protocol,which of the following statements are incorrect regarding link ID of RouterLSA?A in point-to-point link type,link ID is the neighbor’s interface IP address.B In TransNet link type,link ID is the network address of TransNet network segment.C In StubNet link type,link ID is the network address of Stub network.D In virtual link typemlink ID is the neighbor’s Router ID of virtual link.AB34.Which of the following statements are correct regarding how OSPF detects old and duplicateLSAs?A The smaller the sequence number,the more recent the LSA.B The smaller the LS age,the more recent the LSA.C When router generates a new LSA at the first time.it will use 0x80000001 as thesequence number.D An LSA can be flushed from routing domain by setting its LSA age to Maxage.BCD35.OSPF uses SPF algorithm to calculate SPF tree according to topology.which of the followingstatements are correct regarding SPF tree node?A The node on SPF tree indicates router and port.B There are two types of SPF tree node; Transit node and Stub node.C The router node on SPF tree is one type of Stub nodes.D The router node on SPF tree is one type of Transit nodes.BD36.What kind of the BGP attributes does AS-Path attribute belong to ?A MandatoryB TransitiveC OptionalD Non-transitiveAB37.Which of the following statements are correct regarding BGP attribute?A Till now,there are 16 BGP attributesB BGP attribute can be extended to 256 typesC Well-know discretionary attribute may not be included in each BGP update message,suchas Origin attributeD AS_PATH is an Optional Transitive attributeAB38.Which of the following statements belong to BGP COMMUNTY attribute?A NO_EXPORTB NO_ADVIERTISEC LOCAL_EXPORT_SUBCONFEDD NO_BROADCASTABC39.Which of the BGP attributes are Well-known mandatory attributes?A ORIGINB AS_PATHC NEXT_HOPD MEDE LOCAL_PREFF COMMUNITYABC40.Which of the attributes must exist in the BGP Update messages?A LOCAL_PREFB NEXT-HOPC ORIGIND AS_PATHBCD41.Which of the attributes may affect BGP Route Selection?A NEXT_HOPB AS_PATHC LOCAL_PREFD CLUSTER_IDABCD42.Which of the following can be used for BGP route selection?A ACLB IP-PREFIXC AS-PATH-FILTERD COMMUNITY-FILTERABCD43.Which of the following statements about comparison between ACL and IP-PREFIX are true?A Both ACL and IP-PREFIX can be used for route filteringB Both ACL and IP-PREFIX can be used for data packet filteringC ACL can be used for data packet filtering and route filtering,but IP-PREFIX can only beused for route filteringD IP-PREFIX can be used for data packet filtering and route filtering,but ACL can only beused for route filteringAC44.Which of the following statements about ACL type are true?A ACL consists of basic ACL,advanced ACL and interface-based ACLB ACL ranging from 2000 to 2999 belongs to advanced ACLC ACL ranging from 3000 to 3999 belongs to advanced ACLD Advanced ACL can be used to match either destination address or source addressACD45.Which of the following can only be used for BGP route selection?A ACLB IP-PREFIXC AS-PATH-FILTERD COMMUNITY-FILTERCD46.Which of the following statements about VLSM characteristics are true?A VLSM supports both IPv4 and IPv6B VLSM supports overlapped address ranges.C VLSM provides more proper route summarization information in the routing table.D VLSM allows a subnet to be divided into smaller subnets.CD47.Which of the following IP address are network addresses?A 64.104.3.7/28B 192.168.12.64/26C 192.135.12.191/26D 198.18.12.16/28BD48.What are the advantages of subnet division?A Isolating broadcast trafficB Improving network QosC Increasing the IP address usageD Improving network reliabilityAC49.Assume that the subnet mask is 255.255.255.248,which of the following addresses are validhost addresses?A 192.168.200.87B 196.123.142.190C 223.168.210.100D 220.100.100.154BCD50.Which of the following addresses can be used on a public network?A 172.30.0.1/16B 127.254.11.15/16C 172.15.12.7/16D 193.168.10.4/16CD51.Which of the following rules should a network administrator obey when the networkadministrator uses the VLSM technology to plan subnets?A A subnet is composed of all summarized routes.B A subnet can address a host or be further subnetted.C The update message of a routing protocol in use must carry subnet mask information.D The summarized networks must have the same high-order bit.BCD52.Which of the following statements about OSPF authentication are false?A Entering a password in cipher text is allowedB The ospf authentication-mode md5 1 huawei command and the ospfauthentication-mode md5 1 plain Huawei command have the same function.C If passwords are configured for both an area and an interface,the password configuredfor the area is used.D The ospf authentication-mode simple Huawei command and the ospfauthentication-mode simple plain Huawei command have the same function.BC53.Which of the following statements about route summary are true?A advertise is the default parameter of the abr-summary comman,IF neither advertise nornot-advertise is specified in the abr-summary command,advertise is used.B not-advertise is the default parameter of the abr-summary command,If neither advertisenor not-advertise is specified in the abr-summary command,not-advertise is used.C The abr-summary command is run in the OSPF viewD The asbr-summary command is run in the OSPF view.AD54.What are the OSPF message types?A HelloB Database DescriptionC Link state RequestD Link state UpdateE Link state AckABCDE55.What are possible causes for a failure in the establishment of an OSPF neighbor relationship?A Router IDs conflictB Area IDs are mismatchedC Network masks are inconsistentD Authentication types and authentication passwords are inconsistentABCD56.Which statements about OSPF packets are true?A Hello packets can be sent after OSPF is enabled on an interface.B LS Request packets are sent only after an adjacency is established.C LS Update packets contain detailed LSA information for LSDB synchronization.D LS Update packets are sent only after an adjacency is established.ABC57.Which of the following statements about state transition are true?A The neighbor state machine transitions from the loading state to the full state if aloadingdone event occursB The neighbor state machine transitions from the Exstart state to the Full state if aNegotiationdone event occursC The neighbor state machine transitions from the Exchange state to the full state if anExchangedone event occursD The neighbor state machine transitions from the Exchange state to the loading state if anExchangedone event occurs.ACD58.Which of the following statements are true?A The neighbor state machine can transition from the Down state to the attempt stateB The neighbor state machine can transition from the Down state to the init stateC The neighbor state machine can transition from the init state to the Exstart stateD The neighbor state machine can transition from the init state to the 2-way stateABCD59.Which of the following LSAs are flooded within a single area?A Router LSAB Network LSAC Summary LSAD AS External LSAABC60.Which of the following statements about an AS-External-LSA are true?A The Link State ID field specifies the network segment address for an advertiseddestination.B The Advertising Router field specifies the Router ID of an ASBR.C The Net mask field specifies the network mask of an advertised.D The link state ID and Advertising Router fields are used together to uniquely identify anAS-External-LSA.ABC61.Which of the following statements are true?A An LSDB uses a directed graph to show a network topology.The graph contains threeelements:routers,Stub networks,and transit network.B A broadcast network or an NBMA network,each having two or more routers,is a Transitnetwork.C The default value of bandwidth-reference is 10M.D The cost of the route from a Transit network to an attached router is 0.ABD62.Which of the following statements are false?A An ASBR-Summary-LSA describes the route to an ASBR and is flooded within an AS.B An ASE-LSA describes the route to an external AS and is flooded to an external ASC An AS-External-LSA does not belong to any specific area.D The metric of a Type-1 external route is the AS external metric only.ABD63.Which parameters are optional for configuring a BGP peer?A IP addressB DescriptionC PasswordD AS-numberBC64.Which types of packets are supported by BGP?A HelloB NotificationC UpdateD Route-refreshBCD65.Which methods can be used to import local routes to BGP?A Run the network commandB Receive routes from peersC Run the summary automatic commandD Run the import command.AD66.BGP is an inter-AS routing protocol,which statements about BGP are true?A BGP adopts a reliable transmission protocol.B BGP supports automatic peer discovery.C BGP supports incremental route update.D BGP supports various routing policies.ACD67.Which statements about prerequisites to establishing a BGP peer relationship are true?A BGP peers have been manually configured.B A TCP connection has been established between two neighboring routers.C BGP peers have exchanged routing information.D MD5 authentication has been configured on BGP peers.AB68.Which statements about BGP route advertisement are true?A ALL BGP routes learned from BGP peers are advertised to other BGP peers.B Only the routes learned from an IGP are advertised to other BGP peers.C By default,the routes learned from IBGP peers are not advertised to other IBGP peers.D Only the optimal routes are advertised to other BGP peers.CD69.Which of the following conditions must be met for importing routes to BGP by using thenetwork command?A The routes are optimal in the ip routing table.B The routes do not need to match the specified mask length.C The routes match the specified mask lengthD The routes are IGP routes.AC70.Which statements about the AS number range are true?A If 2-byte AS numbers are supported,a private AS number ranges from 32768 to 65535.B IF 2-byte AS numbers are supported,a private AS number ranges from 64512 to 65535.C IF 2-byte AS numbers are supported,an AS number ranges from 1 to 65535.D If 4-byte AS numbers are supported.a 4-byte AS number is in the X.Y format.Here”X”and“y” are integers ranging from 1 to 65535 and 0 to 65535 respectively.BCD71.A notification message with Error Code 2 indicates an error OPEN message.which of thefollowing error sub-codes can be contained in this OPEN message?A 1: indicates that the version number is not supported.B 2: indicates that the AS of the peer is incorrect.C 3: indicates that the BGP identifier is incorrect.D 4: indicates that the Optional parameters filed is not supported.ABCD72.Which parameters are carried in a BGP Open message?A Local AS numberB BGP IDC Keepalive timerD Holder timerE Current peer statusABD73.Which commands are relevant to a BGP route reflector?A peer reflect-clientB reflect between-clientsC reflector cluster-idD rr-filterABCD74.Which statements about the process of establishing a BGP peer relationship are true?A There may by two TCP connections during the establishment of the BGP peerrelationship.B IF two TCP connections are established between BGP peers,one connection functions asthe primary connection,and the other as the backup connection.C IF two TCP connections are established between BGP peers,one TCP connection is torndown.D IF there are multiple TCP connections between BGP peers,BGP keeps the TCP connectioninitiated by the peer with a greater BGP router ID.ACD75.Which statements about BGP route reflection are true?A IBGP peers must be fully connected in absence of a route reflector(RR),The BGP routereflection mechanism is introduced to lower the requirement.B After learning routes from a non-client,a route reflector(RR) advertises these routes to allclients.C After learning routes from a client,an RR advertises these routes to all clients andnon-clients.D After learning routes from an EBGP peer,an RR advertises these routes to all clients andnon-clients.ABCD76.In a route-policy,which BGP attributes can be invoked by if-match clauses?A Local-PreferenceB AS-PathC MEDD CommunityBCD77.In a route-policy,which BGP attributes can be used to define apply clauses?A Local-PreferenceB TagC OriginD AS-PathACD78.Which BGP attributes are optional in a BGP update packet?A OriginB NexthopC Local-PreferenceD MEDCD79.Which statements about BGP well-known mandatory attributes are true?A Well-known mandatory attributes must be identified by all BGP routers.B Well-known mandatory attributes must be transmitted between BGP peers.C Well-known mandatory attributes are optional in an Update packet,and can be carried inan Update packet as needed.D Well-known mandatory attributes must be carried in an Update packet.ABD80.in OSPF,which of the following statements are incorrect regarding Router LSA generated byRouter A?A In point-to-point link type,data is set to the interface IP address of RouterA.B In transNet link type, data is set to the interface IP address of RouterA.C In StubNet link type,data is set to the interface IP address of RouterA.D In Virtual link type, data is set to the Router ID of RouterA.CD81.which attributes are well-known community attributes?A NO_EXPORT (0xFFFFFF01)B NO_ADVERTISE(0xFFFFFF02)C NO_EXPORT_SUBCONFEDD AS(2Byte):Number(2Byte)ABC82.which statements about BGP route selection rules are true?A BGP first ignores routes with unreachable next hops.B A summarized route takes precedence over a non-summarized route.C EBGP routes take precedence over IBGP routes.D IF other conditions of routes are the same,the route with the shortest cluster_list ispreferred.ABCD83.which BGP attributes can be used to prevent routing loops?A originator_IDB AggregatorC Cluster_listD AS-PathACD84.which of the following BGP routing policies can be used to filter routes?A ip-prefixB route-policyC as-path-filerD community-filterABCD85.which attributes meet the following two conditions:(1)A BGP router (Router A)can choosewhether to carry this attribute in an update packet.(2) If a receiving router(Router B )cannot identify this attribute,this router can advertise this attribute to another BGP router (RouterC).Router C may be able to identify and use this attribute.A AggregatorB Local_prefC multi_exit_discD CommunityAD86.which of the following route selection tools can be used only in BGP?A Route-policyB IP-prefixC AS-path-filterD Community-filterCD87.which of the following routing protocols support import-route?A OSPFB RIPC BGPABC88.which of the following routes match this ACL filter? Acl number 2001 rule 0 permit source1.1.1.0 0.0.254.255A 1.1.1.1/32B 1.1.2.1/32C 1.1.3.1/32D 1.1.4.1/32AC89.which of the following route prefixes match this IP-prefix-filter? IP ip-prefix test index 10permit 10.0.0.0 16 greater-equal 24 less-equal 28A 10.0.1.0/23B 10.0.1.0/24C 10.0.1.0/25D 10.0.1.0/28BCD90.one route selection tool may have several Items defined,to which of following tools will thesystem automatically add a deny-any item following all the configured items?A ACLB IP-prefixC AS-path-filterD community-filterABCD91.which of the following methods are supported by OSPF for delivering default routes?A Delivery by an ABRB Delivery by an ASBRC Forcible deliveryD Non-forcible deliveryABCD92.which of the following scenarios can an AS-path-filter be used for?A Filtering the routes received from a BGP peer based on the as-path attributes of theroutes,for example,peer X.X.X.X as-path-filter importB Filtering the routes sent to a BGP peer based on the as-path attributes of the routes,forexample,peer X.X.X.X as-path-filter exportC Apply clauses in a route-policyD IF-match clauses in a route-policyABD93.which of the following protocols support default route advertisement by using commands?A RIPB OSPFC BGPABC94.which of the following as-path attributes match this AS-path-filter? Ip AS-path-filter 1permit 100$|400$A 100B 3100C 1234 1400D 300 400ABCD。

托福TPO8阅读真题Part2文本及题目答案

托福TPO8阅读真题Part2文本及题目答案托福TPO是我们托福阅读的重要参考资料，为了方便大家备考，下面小编给大家整理了托福TPO8阅读真题Part2文本及题目答案，希望大家喜欢。

托福TPO8阅读真题Part2Extinction of the DinosaursPaleozoic Era 334 to 248 million years agoMesozoic Era 245 to 65 million years ago-Triassic Period-Jurassic Period-Cretaceous PeriodCenozoic Era 65 million years ago to the presentPaleontologists have argued for a long time that the demise of the dinosaurs was caused by climatic alterations associated with slow changes in the positions of continents and seas resulting from plate tectonics. Off and on throughout the Cretaceous (the last period of the Mesozoic era, during which dinosaurs flourished), large shallow seas covered extensive areas of the continents. Data from diverse sources, including geochemical evidence preserved in seafloor sediments, indicate that the Late Cretaceous climate was milder than today's. The days were not too hot, nor the nights too cold. The summers were not too warm, nor the winters too frigid. The shallow seas on the continents probably buffered the temperature of the nearby air, keeping it relatively constant.At the end of the Cretaceous, the geological record shows that these seaways retreated from the continents back into the major ocean basins. No one knows why. Over a period of about 100,000 years, while the seas pulled back, climates around theworld became dramatically more extreme: warmer days, cooler nights; hotter summers, colder winters. Perhaps dinosaurs could not tolerate these extreme temperature changes and became extinct.If true, though, why did cold-blooded animals such as snakes, lizards, turtles, and crocodiles survive the freezing winters and torrid summers? These animals are at the mercy of the climate to maintain a livable body temperature. It's hard to understand why they would not be affected, whereas dinosaurs were left too crippled to cope, especially if, as some scientists believe, dinosaurs were warm-blooded. Critics also point out that the shallow seaways had retreated from and advanced on the continents numerous times during the Mesozoic, so why did the dinosaurs survive the climatic changes associated with the earlier fluctuations but not with this one? Although initially appealing, the hypothesis of a simple climatic change related to sea levels is insufficient to explain all the data.Dissatisfaction with conventional explanations for dinosaur extinctions led to a surprising observation that, in turn, has suggested a new hypothesis. Many plants and animals disappear abruptly from the fossil record as one moves from layers of rock documenting the end of the Cretaceous up into rocks representing the beginning of the Cenozoic (the era after the Mesozoic). Between the last layer of Cretaceous rock and the first layer of Cenozoic rock, there is often a thin layer of clay. Scientists felt that they could get an idea of how long the extinctions took by determining how long it took to deposit this one centimeter of clay and they thought they could determine the time it took to deposit the clay by determining the amount of the element iridium (Ir) it contained.Ir has not been common at Earth's since the very beginning of the planet's history. Because it usually exists in a metallic state, it was preferentially incorporated in Earth's core as the planet cooled and consolidated. Ir is found in high concentrations in some meteorites, in which the solar system's original chemical composition is preserved. Even today, microscopic meteorites continually bombard Earth, falling on both land and sea. By measuring how many of these meteorites fall to Earth over a given period of time, scientists can estimate how long it might have taken to deposit the observed amount of Ir in the boundary clay. These calculations suggest that a period of about one million years would have been required. However, other reliable evidence suggests that the deposition of the boundary clay could not have taken one million years. So the unusually high concentration of Ir seems to require a special explanation.In view of these facts, scientists hypothesized that a single large asteroid, about 10 to 15 kilometers across, collided with Earth, and the resulting fallout created the boundary clay. Their calculations show that the impact kicked up a dust cloud that cut off sunlight for several months, inhibiting photosynthesis in plants; decreased surface temperatures on continents to below freezing; caused extreme episodes of acid rain; and significantly raised long-term global temperatures through the greenhouse effect. This disruption of food chain and climate would have eradicated the dinosaurs and other organisms in less than fifty years.Paragraph 1: Paleontologists have argued for a long time that the demise of the dinosaurs was caused by climatic alterations associated with slow changes in the positions of continents and seas resulting from plate tectonics. Off and onthroughout the Cretaceous (the last period of the Mesozoic era, during which dinosaurs flourished), large shallow seas covered extensive areas of the continents. Data from diverse sources, including geochemical evidence preserved in seafloor sediments, indicate that the Late Cretaceous climate was milder than today's. The days were not too hot, nor the nights too cold. The summers were not too warm, nor the winters too frigid. The shallow seas on the continents probably buffered the temperature of the nearby air, keeping it relatively constant.托福TPO8阅读题目Part21. According to paragraph 1, which of the following is true of the Late Cretaceous climate?○Summers were very warm and winters were very cold.○Shallow seas on the continents caused frequent temperature changes.○The climate was very similar to today's climate.○The climate did not change dramatically from season to season.Paragraph 2: At the end of the Cretaceous, the geological record shows that these seaways retreated from the continents back into the major ocean basins. No one knows why. Over a period of about 100,000 years, while the seas pulled back, climates around the world became dramatically more extreme: warmer days, cooler nights; hotter summers, colder winters. Perhaps dinosaurs could not tolerate these extreme temperature changes and became extinct.2. Which of the following reasons is suggested in paragraph 2 for the extinction of the dinosaurs?○Changes in the lengths of the days and nights during the late Cretaceous period○Droughts caused by the movement of seaways back into the oceans○The change from mild to severe climates during the Late Cretaceous period○An extreme decrease in the average yearly temperature over 10,ooo yearsParagraph 3: If true, though, why did cold-blooded animals such as snakes, lizards, turtles, and crocodiles survive the freezing winters and torrid summers? These animals are at the mercy of the climate to maintain a livable body temperature. It's hard to understand why they would not be affected, whereas dinosaurs were left too crippled to cope, especially if, as some scientists believe, dinosaurs were warm-blooded. Critics also point out that the shallow seaways had retreated from and advanced on the continents numerous times during the Mesozoic, so why did the dinosaurs survive the climatic changes associated with the earlier fluctuations but not with this one? Although initially appealing, the hypothesis of a simple climatic change related to sea levels is insufficient to explain all the data.3. Why does the author mention the survival of "snakes, lizards, turtles, and crocodiles" in paragraph 3?○To argue that dinosaurs ma y have become extinct because they were not cold-blooded animals○To question the adequacy of the hypothesis that climatic change related to sea levels caused the extinction of the dinosaurs○To present examples of animals that could maintain a livable body temperature more easily than dinosaurs ○To support a hypothesis that these animals were not as sensitive to climate changes in the Cretaceous period as they aretoday4. The word "cope" in the passage is closest in meaning to○ adapt○ move○ continue○ compete5. According to paragraph 3, which of the following is true of changes in climate before the Cretaceous period and the effect of these changes on dinosaurs?○Climate changes associated with the movement of seaways before the Cretaceous period did not cause dinosaurs to become extinct.○Changes in climate before the Cretaceous period caused severe fluctuations in sea level, resulting in the extinction of the dinosaurs.○Frequent changes in climate before the Cretaceous period made dinosaurs better able to maintain a livable body temperature.○Before the Cretaceous period there were few changes in climate, and dinosaurs flourished.6.The word "fluctuations" in the passage is closest in meaning to○ extremes○ retreats○ periods○ variationsParagraph 4: Dissatisfaction with conventional explanations for dinosaur extinctions led to a surprising observation that, in turn, has suggested a new hypothesis. Many plants and animals disappear abruptly from the fossil record as one moves fromlayers of rock documenting the end of the Cretaceous up into rocks representing the beginning of the Cenozoic (the era after the Mesozoic). Between the last layer of Cretaceous rock and the first layer of Cenozoic rock, there is often a thin layer of clay. Scientists felt that they could get an idea of how long the extinctions took by determining how long it took to deposit this one centimeter of clay and they thought they could determine the time it took to deposit the clay by determining the amount of the element iridium (lr) it contained.7. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? In correct choices change the meaning in important ways or leave out essential information.○The fossil record suggests t hat there was an abrupt extinction of many plants and animals at the end of the Mesozoic era.○Few fossils of the Mesozoic era have survived in the rocks that mark the end of the Cretaceous.○Fossils from the Cretaceous period of the Mesozoic up to the beginning of the Cenozoic era have been removed from the layers of rock that surrounded them.○Plants and animals from the Mesozoic era were unable to survive in the Cenozoic era.Paragraph 4: Dissatisfaction with conventional explanations for dinosaur extinctions led to a surprising observation that, in turn, has suggested a new hypothesis. Many plants and animals disappear abruptly from the fossil record as one moves from layers of rock documenting the end of the Cretaceous up into rocks representing the beginning of the Cenozoic (the era after the Mesozoic). Between the last layer of Cretaceous rock and thefirst layer of Cenozoic rock, there is often a thin layer of clay. Scientists felt that they could get an idea of how long the extinctions took by determining how long it took to deposit this one centimeter of clay and they thought they could determine the time it took to deposit the clay by determining the amount of the element iridium (Ir) it contained.8. In paragraph 4, all the following questions are answered EXCEPT:○Why is there a layer of clay between the rocks of the Cretaceous and Cenozoic?○Why were scientists interested in determining how long it took to deposit the layer of clay at the end of the Cretaceous?○What was the effect of the surprisi ng observation scientists made?○Why did scientists want more information about the dinosaur extinctions at the end of the Cretaceous?Paragraph 5: Ir has not been common at Earth's since the very beginning of the planet's history. Because it usually exists in a metallic state, it was preferentially incorporated in Earth's core as the planet cooled and consolidated. Ir is found in high concentrations in some meteorites, in which the solar system's original chemical composition is preserved. Even today, microscopic meteorites continually bombard Earth, falling on both land and sea. By measuring how many of these meteorites fall to Earth over a given period of time, scientists can estimate how long it might have taken to deposit the observed amount of Ir in the boundary clay. These calculations suggest that a period of about one million years would have been required. However, other reliable evidence suggests that the deposition of the boundary clay could not have taken one million years. So theunusually high concentration of Ir seems to require a special explanation.9. The word "bombard" in the passage is closest in meaning to○ approach○ strike○ pass○ circle10. Paragraph 5 implies that a special explanation of Ir in the boundary clay is needed because○t he Ir in microscopic meteorites reaching Earth during the Cretaceous period would have been incorporated into Earth's core○the Ir in the boundary clay was deposited much more than a million years ago○the concentration of Ir in the boundary clay is higher than in microscopic meteorites○the amount of Ir in the boundary clay is too great to have come from microscopic meteorites during the time the boundary clay was depositedParagraph 6: In view of these facts, scientists hypothesized that a single large asteroid, about 10 to 15 kilometers across, collided with Earth, and the resulting fallout created the boundary clay. Their calculations show that the impact kicked up a dust cloud that cut off sunlight for several months, inhibiting photosynthesis in plants; decreased surface temperatures on continents to below freezing; caused extreme episodes of acid rain; and significantly raised long-term global temperatures through the greenhouse effect. This disruption of food chain and climate would have eradicated the dinosaurs and otherorganisms in less than fifty years.11. The word "disruption" in the passage is closest in meaning to○ exhaustion○ disturbance○ modification○ disappearance12. Paragraph 6 mentions all of the following effects of the hypothesized asteroid collision EXCEPT○ a large dust cloud that blocked sunlight○ an immediate drop in the surface temperatures of the continents○ an extreme decrease in rainfall on the continents○ a long-term increase in global temperaturesParagraph 5: Ir has not been common at Earth's since the very beginning of the planet's history. Because it usually exists in a metallic state, it was preferentially incorporated in Earth's core as the planet cooled and consolidated. Ir is found in high concentrations in some meteorites, in which the solar system's original chemical composition is preserved. Even today, microscopic meteorites continually bombard Earth, falling on both land and sea. By measuring how many of these meteorites fall to Earth over a given period of time, scientists can estimate how long it might have taken to deposit the observed amount of Ir in the boundary clay. ■ These calculations suggest that a period of about one million years would have been required. ■However, other reliable evidence suggests that the deposition of the boundary clay could not have taken one million years. ■So the unusually high concentration of Ir seems to require a special explanation. ■13. Look at the four squares [■] that indicate where the following sentence could be added to the passage.Consequently, the idea that the Ir in the boundary clay came from microscopic meteorites cannot be accepted.Where would the sentence best fit?14. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.For a long time scientists have argued that the extinction of the dinosaurs was related to climate change.●●●Answer choices○A simple climate change does not explain some important data related to the extinction of the dinosaurs at the end of the Cretaceous.○The retreat of the seaways at the end of the Cretaceous has not been fully explained.○The abruptness of extinctions at the end of the Cretaceous and the high concentration of Ir found in clay deposited at that time have fueled the development of a new hypothesis.○Extreme changes in daily and seasonal climates preceded the retreat of the seas back into the major ocean basins.○Some scientists hypothesize that the extinction of the dinosaurs resulted from the effects of an asteroid collision withEarth.○Boundary clay layers like the one between the Mesozoic and Cenozoic are used by scientists to determine the rate at which an extinct species declined托福TPO8阅读答案Part2参考答案：1. ○42. ○33. ○24. ○15. ○16. ○47. ○18.○19. ○210. ○411. ○212. ○313. ○314. A simple climate changeThe abruptness of extinctionsSome scientists hypothesize托福TPO8阅读翻译：Part2参考翻译：恐龙的灭绝很长时间以来，古生物学家们认为恐龙的灭亡是与因地质构造而引起的海洋和大陆位置变迁相关的气候变化所致。

化学专业术语词根词缀

造福人民群众。

重新上传份积分合理点的。

科技英语中的常见词根第二篇术语A1.(词头)无、缺[……希”a-或an-(于元音前)义为无、缺少或不]anaerobe厌氧菌[an-+aero-空气+“希”bios生命]an(a)emia贫血[an-+-emia血症]aseptic无菌的[a-+“希”sepsis腐烂，septikos致腐的]．atom原子[a-+“希”tomos分割]atrophy萎缩[a-+“希”~ophe营养+-y名词词尾]2.ab-，abs-(词头)脱离，离开l=……拉”ab-义为从，离开，在远处，在外，在m、p、v之前用a-，在c、q、t之前则为abs-]abnormal异常的[ab-+normal正常的]3.abio-(复合形)无生物[a-无+“希”bios生命]abiochemisty无机化学[abio-+chemisty化学]abiogenesis无生原说[abio-+genesis发生]abiotrophy营养不足，生活力缺乏[abio-+-trophy营养]4.acro-(复合形)尖端，肢端[“希”akron峰，顶点，最高点]acrocephalia尖头[acro-+cephalo-头+-ia状态]acrohyperhidrosis手足多汗[acro- +hyper-多+hidrosis出汗]acrophobia高处恐怖[acro-+-phobia恐怖]5.actino-(复合形)光线，射线[“希”aktis，所有格akfinos光线，光束]actinochemistry光化学[actino-+chemistry化学]actinogram x线照片[actino-+-gram描记图]actinomycetes放线菌属[acfino-+mycete霉菌]actinotherapy射线疗法[actino-+therapy治疗]6.ad- (词头)近，向[“拉”ad向着，对着，在近边，在上，增加等。

难治性复发性多发性骨髓瘤治疗策略ppt课件.ppt

复发时间如何对治疗选择产生影响？
High vs Standard Risk
High-risk: Patients with adverse cytogenetics, aggressive clinical features, short duration of response to prior therapy, or progression on current treatment Standard-risk: Those with absence of adverse cytogenetics, indolent clinical features, and prolonged response to previous therapy
一线治疗包括
基于IMiD的方案：CTD,MPT, RD 或 Rd
基于Bortezomib的方案：VMP或VD
基于Bortezomib的方案† Bortezomib+/-Dex Bortezomib/PLD * VTD * VCD PAD
基于IMiD的方案 Len/Dex * CRD Thal/Dex CTD
MM联合用药的理论机制
Anderson. Hematology , 2011:184–190
硼替佐米+蒽环类治疗复发/难治性MM疗效
Bortezomib regimen
Phase
n
CR + PR
CR + nCR
Reference
+ Doxil
III
303
52%
17%
Harousseau et al. J Clin Oncol 2007; 25(18S): Abstract 8002 (Oral Presentation)

农场上有很多羊吗英语作文

In the heart of the countryside,there lies a quaint farm that is home to a multitude of sheep.This farm is a testament to the rural lifestyle,where the bleating of the sheep is a constant reminder of the natural rhythm of life.The sheep are an integral part of the farms ecosystem,contributing to the landscape and the livelihood of the farmers.The farm is surrounded by lush green fields that provide an ideal grazing ground for the sheep.The fields are carefully managed to ensure that the grass is always fresh and nutritious,which is essential for the health and wellbeing of the flock.The farmers take great pride in maintaining the quality of the pasture,as it directly impacts the quality of the wool and meat produced by the sheep.The sheep on the farm are a mix of different breeds,each with their own unique characteristics.Some of the breeds include the Merino,known for its fine wool,the Suffolk,renowned for its meat,and the Jacob,which is prized for its distinctive horns and hardy nature.The diversity of the breeds allows the farmers to cater to different markets and ensures that the farm remains sustainable in the long run.The daily routine on the farm revolves around the care and management of the sheep.The farmers start their day early,checking on the flock and ensuring that they have access to clean water and food.They also monitor the health of the sheep,looking out for any signs of illness or injury.Regular shearing is an essential part of the process,as it helps to maintain the quality of the wool and keeps the sheep comfortable during the warmer months.In addition to the sheep,the farm is also home to other animals such as chickens,cows, and pigs.These animals coexist harmoniously,each contributing to the overall productivity of the farm.The chickens provide eggs and the cows supply milk,while the pigs are raised for meat.This diversity of livestock ensures that the farm is selfsufficient and can provide a variety of products to the local community.The farmers also engage in other agricultural activities,such as growing crops and tending to orchards.The produce from these activities is used to supplement the diet of the animals and is also sold at the local market.This helps to diversify the farms income and makes it more resilient to changes in the market.The farm is a hub of activity,with the sheep playing a central role in the daily operations. Their presence is a constant reminder of the importance of agriculture in sustaining rural communities.The farmers take great pride in their work,knowing that they are contributing to the preservation of a way of life that has been passed down through generations.In conclusion,the farm with its many sheep is a symbol of the rural lifestyle and the importance of agriculture in our society.The sheep,along with the other animals and crops,form the backbone of the farms operations,providing sustenance and income for the farmers.The farm is a testament to the hard work and dedication of the farmers,who strive to maintain the quality of their products and preserve the natural beauty of the countryside.。

投资学第7版Test Bank答案15

Multiple Choice Questions1. The term structure of interest rates is:A) The relationship between the rates of interest on all securities.B) The relationship between the interest rate on a security and its time to maturity.C) The relationship between the yield on a bond and its default rate.D) All of the above.E) None of the above.Answer: B Difficulty: EasyRationale: The term structure of interest rates is the relationship between two variables, years and yield to maturity (holding all else constant).2. The yield curve shows at any point in time:A) The relationship between the yield on a bond and the duration of the bond.B) The relationship between the coupon rate on a bond and time to maturity of thebond.C) The relationship between yield on a bond and the time to maturity on the bond.D) All of the above.E) None of the above.Answer: C Difficulty: Easy3. An inverted yield curve implies that:A) Long-term interest rates are lower than short-term interest rates.B) Long-term interest rates are higher than short-term interest rates.C) Long-term interest rates are the same as short-term interest rates.D) Intermediate term interest rates are higher than either short- or long-term interestrates.E) none of the above.Answer: A Difficulty: EasyRationale: The inverted, or downward sloping, yield curve is one in which short-term rates are higher than long-term rates. The inverted yield curve has been observedfrequently, although not as frequently as the upward sloping, or normal, yield curve.4. An upward sloping yield curve is a(n) _______ yield curve.A) normal.B) humped.C) inverted.D) flat.E) none of the above.Answer: A Difficulty: EasyRationale: The upward sloping yield curve is referred to as the normal yield curve, probably because, historically, the upward sloping yield curve is the shape that has been observed most frequently.5. According to the expectations hypothesis, a normal yield curve implies thatA) interest rates are expected to remain stable in the future.B) interest rates are expected to decline in the future.C) interest rates are expected to increase in the future.D) interest rates are expected to decline first, then increase.E) interest rates are expected to increase first, then decrease.Answer: C Difficulty: EasyRationale: An upward sloping yield curve is based on the expectation that short-term interest rates will increase.6. Which of the following is not proposed as an explanation for the term structure ofinterest rates?A) The expectations theory.B) The liquidity preference theory.C) The market segmentation theory.D) Modern portfolio theory.E) A, B, and C.Answer: D Difficulty: EasyRationale: A, B, and C are all theories that have been proposed to explain the term structure.7. The expectations theory of the term structure of interest rates states thatA) forward rates are determined by investors' expectations of future interest rates.B) forward rates exceed the expected future interest rates.C) yields on long- and short-maturity bonds are determined by the supply and demandfor the securities.D) all of the above.E) none of the above.Answer: A Difficulty: EasyRationale: The forward rate equals the market consensus expectation of future short interest rates.8. Which of the following theories state that the shape of the yield curve is essentiallydetermined by the supply and demands for long-and short-maturity bonds?A) Liquidity preference theory.B) Expectations theory.C) Market segmentation theory.D) All of the above.E) None of the above.Answer: C Difficulty: EasyRationale: Market segmentation theory states that the markets for different maturities are separate markets, and that interest rates at the different maturities are determined by the intersection of the respective supply and demand curves.9. According to the "liquidity preference" theory of the term structure of interest rates, theyield curve usually should be:A) inverted.B) normal.C) upward slopingD) A and B.E) B and C.Answer: E Difficulty: EasyRationale: According to the liquidity preference theory, investors would prefer to be liquid rather than illiquid. In order to accept a more illiquid investment, investors require a liquidity premium and the normal, or upward sloping, yield curve results.Use the following to answer questions 10-13:Suppose that all investors expect that interest rates for the 4 years will be as follows:10. What is the price of 3-year zero coupon bond with a par value of $1,000?A) $B) $C) $D) $E) none of the aboveAnswer: B Difficulty: ModerateRationale: $1,000 / = $11. If you have just purchased a 4-year zero coupon bond, what would be the expected rateof return on your investment in the first year if the implied forward rates stay the same?(Par value of the bond = $1,000)A) 5%B) 7%C) 9%D) 10%E) none of the aboveAnswer: A Difficulty: ModerateRationale: The forward interest rate given for the first year of the investment is given as 5% (see table above).12. What is the price of a 2-year maturity bond with a 10% coupon rate paid annually? (Parvalue = $1,000)A) $1,092B) $1,054C) $1,000D) $1,073E) none of the aboveAnswer: D Difficulty: ModerateRationale: []1/2 - 1 = 6%; FV = 1000, n = 2, PMT = 100, i = 6, PV = $1,13. What is the yield to maturity of a 3-year zero coupon bond?A) %B) %C) %D) %E) none of the aboveAnswer: C Difficulty: ModerateRationale: []1/3 - 1 = .Use the following to answer questions 14-16:The following is a list of prices for zero coupon bonds with different maturities and par value of $1,000.14. What is, according to the expectations theory, the expected forward rate in the thirdyear?A) %B) %C) %D) %E) none of the aboveAnswer: C Difficulty: ModerateRationale: / - 1 = 9%15. What is the yield to maturity on a 3-year zero coupon bond?A) %B) %C) %D) %E) none of the aboveAnswer: C Difficulty: ModerateRationale: (1000 / 1/3 -1 = %16. What is the price of a 4-year maturity bond with a 12% coupon rate paid annually? (Parvalue = $1,000)A) $B) $1,C) $1,D) $1,E) none of the aboveAnswer: D Difficulty: DifficultRationale: (1000 / 1/4 -1 = %; FV = 1000, PMT = 120, n = 4, i = , PV = $1,17. The market segmentation theory of the term structure of interest ratesA) theoretically can explain all shapes of yield curves.B) definitely holds in the "real world".C) assumes that markets for different maturities are separate markets.D) A and B.E) A and C.Answer: E Difficulty: EasyRationale: Although this theory is quite tidy theoretically, both investors and borrows will depart from their "preferred maturity habitats" if yields on alternative maturities are attractive enough.18. An upward sloping yield curveA) may be an indication that interest rates are expected to increase.B) may incorporate a liquidity premium.C) may reflect the confounding of the liquidity premium with interest rateexpectations.D) all of the above.E) none of the above.Answer: D Difficulty: EasyRationale: One of the problems of the most commonly used explanation of termstructure, the expectations hypothesis, is that it is difficult to separate out the liquidity premium from interest rate expectations.19. The "break-even" interest rate for year n that equates the return on an n-periodzero-coupon bond to that of an n-1-period zero-coupon bond rolled over into a one-year bond in year n is defined asA) the forward rate.B) the short rate.C) the yield to maturity.D) the discount rate.E) None of the above.Answer: A Difficulty: EasyRationale: The forward rate for year n, fn, is the "break-even" interest rate for year n that equates the return on an n-period zero- coupon bond to that of an n-1-periodzero-coupon bond rolled over into a one-year bond in year n.20. When computing yield to maturity, the implicit reinvestment assumption is that theinterest payments are reinvested at the:A) Coupon rate.B) Current yield.C) Yield to maturity at the time of the investment.D) Prevailing yield to maturity at the time interest payments are received.E) The average yield to maturity throughout the investment period.Answer: C Difficulty: ModerateRationale: In order to earn the yield to maturity quoted at the time of the investment, coupons must be reinvested at that rate.21. Which one of the following statements is true?A) The expectations hypothesis indicates a flat yield curve if anticipated futureshort-term rates exceed the current short-term rate.B) The basic conclusion of the expectations hypothesis is that the long-term rate isequal to the anticipated long-term rate.C) The liquidity preference hypothesis indicates that, all other things being equal,longer maturities will have lower yields.D) The segmentation hypothesis contends that borrows and lenders are constrained toparticular segments of the yield curve.E) None of the above.Answer: D Difficulty: ModerateRationale: A flat yield curve indicates expectations of existing rates. Expectations hypothesis states that the forward rate equals the market consensus of expectations of future short interest rates. The reverse of C is true.22. The concepts of spot and forward rates are most closely associated with which one ofthe following explanations of the term structure of interest rates.A) Segmented Market theoryB) Expectations HypothesisC) Preferred Habitat HypothesisD) Liquidity Premium theoryE) None of the aboveAnswer: B Difficulty: ModerateRationale: Only the expectations hypothesis is based on spot and forward rates. A andC assume separate markets for different maturities; liquidity premium assumes higheryields for longer maturities.Use the following to answer question 23:23. Given the bond described above, if interest were paid semi-annually (rather thanannually), and the bond continued to be priced at $850, the resulting effective annual yield to maturity would be:A) Less than 12%B) More than 12%C) 12%D) Cannot be determinedE) None of the aboveAnswer: B Difficulty: ModerateRationale: FV = 1000, PV = -850, PMT = 50, n = 40, i = (semi-annual); 2 - 1 = %.24. Interest rates might declineA) because real interest rates are expected to decline.B) because the inflation rate is expected to decline.C) because nominal interest rates are expected to increase.D) A and B.E) B and C.Answer: D Difficulty: EasyRationale: The nominal rate is comprised of the real interest rate plus the expectedinflation rate.25. Forward rates ____________ future short rates because ____________.A) are equal to; they are both extracted from yields to maturity.B) are equal to; they are perfect forecasts.C) differ from; they are imperfect forecasts.D) differ from; forward rates are estimated from dealer quotes while future short ratesare extracted from yields to maturity.E) are equal to; although they are estimated from different sources they both are usedby traders to make purchase decisions.Answer: C Difficulty: EasyRationale: Forward rates are the estimates of future short rates extracted from yields to maturity but they are not perfect forecasts because the future cannot be predicted with certainty; therefore they will usually differ.26. The pure yield curve can be estimatedA) by using zero-coupon bonds.B) by using coupon bonds if each coupon is treated as a separate "zero."C) by using corporate bonds with different risk ratings.D) by estimating liquidity premiums for different maturities.E) A and B.Answer: E Difficulty: ModerateRationale: The pure yield curve is calculated using zero coupon bonds, but coupon bonds may be used if each coupon is treated as a separate "zero."27. The on the run yield curve isA) a plot of yield as a function of maturity for zero-coupon bonds.B) a plot of yield as a function of maturity for recently issued coupon bonds trading ator near par.C) a plot of yield as a function of maturity for corporate bonds with different riskratings.D) a plot of liquidity premiums for different maturities.E) A and B.Answer: B Difficulty: Moderate28. The market segmentation and preferred habitat theories of term structureA) are identical.B) vary in that market segmentation is rarely accepted today.C) vary in that market segmentation maintains that borrowers and lenders will notdepart from their preferred maturities and preferred habitat maintains that marketparticipants will depart from preferred maturities if yields on other maturities areattractive enough.D) A and B.E) B and C.Answer: E Difficulty: ModerateRationale: Borrowers and lenders will depart from their preferred maturity habitats if yields are attractive enough; thus, the market segmentation hypothesis is no longerreadily accepted.29. The yield curveA) is a graphical depiction of term structure of interest rates.B) is usually depicted for U. S. Treasuries in order to hold risk constant acrossmaturities and yields.C) is usually depicted for corporate bonds of different ratings.D) A and B.E) A and C.Answer: D Difficulty: EasyRationale: The yield curve (yields vs. maturities, all else equal) is depicted for U. S.Treasuries more frequently than for corporate bonds, as the risk is constant acrossmaturities for Treasuries.Use the following to answer questions 30-32:30. What should the purchase price of a 2-year zero coupon bond be if it is purchased at thebeginning of year 2 and has face value of $1,000?A) $B) $C) $D) $E) $Answer: A Difficulty: DifficultRationale: $1,000 / [] = $31. What would the yield to maturity be on a four-year zero coupon bond purchased today?A) %B) %C) %D) %E) none of the above.Answer: C Difficulty: ModerateRationale: [ ]1/4 - 1 = %32. Calculate the price at the beginning of year 1 of a 10% annual coupon bond with facevalue $1,000 and 5 years to maturity.A) $1,105B) $1,132C) $1,179D) $1,150E) $1,119Answer: B Difficulty: DifficultRationale: i = [ ]1/5 - 1 = %; FV = 1000, PMT = 100, n = 5, i = , PV = $1,33. Given the yield on a 3 year zero-coupon bond is % and forward rates of % in year 1and % in year 2, what must be the forward rate in year 3?A) %B) %C) %D) %E) none of the above.Answer: B Difficulty: ModerateRationale: f3 = 3 / [ ] - 1 = %34. An inverted yield curve is oneA) with a hump in the middle.B) constructed by using convertible bonds.C) that is relatively flat.D) that plots the inverse relationship between bond prices and bond yields.E) that slopes downward.Answer: E Difficulty: EasyRationale: An inverted yield curve occurs when short-term rates are higher thanlong-term rates.35. Investors can use publicly available financial date to determine which of the following?I)the shape of the yield curveII)future short-term ratesIII)the direction the Dow indexes are headingIV)the actions to be taken by the Federal ReserveA) I and IIB) I and IIIC) I, II, and IIID) I, III, and IVE) I, II, III, and IVAnswer: A Difficulty: ModerateRationale: Only the shape of the yield curve and future inferred rates can be determined.The movement of the Dow Indexes and Federal Reserve policy are influenced by term structure but are determined by many other variables also.36. Which of the following combinations will result in a sharply increasing yield curve?A) increasing expected short rates and increasing liquidity premiumsB) decreasing expected short rates and increasing liquidity premiumsC) increasing expected short rates and decreasing liquidity premiumsD) increasing expected short rates and constant liquidity premiumsE) constant expected short rates and increasing liquidity premiumsAnswer: A Difficulty: ModerateRationale: Both of the forces will act to increase the slope of the yield curve.37. The yield curve is a component ofA) the Dow Jones Industrial Average.B) the consumer price index.C) the index of leading economic indicators.D) the producer price index.E) the inflation index.Answer: C Difficulty: EasyRationale: Since the yield curve is often used to forecast the business cycle, it is used as one of the leading economic indicators.38. The most recently issued Treasury securities are calledA) on the run.B) off the run.C) on the market.D) off the market.E) none of the above.Answer: A Difficulty: EasyUse the following to answer questions 39-42:Suppose that all investors expect that interest rates for the 4 years will be as follows:39. What is the price of 3-year zero coupon bond with a par value of $1,000?A) $B) $C) $D) $E) none of the aboveAnswer: A Difficulty: ModerateRationale: $1,000 / = $40. If you have just purchased a 4-year zero coupon bond, what would be the expected rateof return on your investment in the first year if the implied forward rates stay the same?(Par value of the bond = $1,000)A) 5%B) 3%C) 9%D) 10%E) none of the aboveAnswer: B Difficulty: ModerateRationale: The forward interest rate given for the first year of the investment is given as 3% (see table above).41. What is the price of a 2-year maturity bond with a 5% coupon rate paid annually? (Parvalue = $1,000)A) $1,B) $1,C) $1,D) $1,E) none of the aboveAnswer: C Difficulty: ModerateRationale: []1/2 - 1 = %; FV = 1000, n = 2, PMT = 50, i = , PV = $1,42. What is the yield to maturity of a 3-year zero coupon bond?A) %B) %C) %D) 4%E) none of the aboveAnswer: D Difficulty: ModerateRationale: []1/3 - 1 = 4%.Use the following to answer questions 43-46:The following is a list of prices for zero coupon bonds with different maturities and par value of $1,000.43. What is, according to the expectations theory, the expected forward rate in the thirdyear?A)B) %C) %D) %E) none of the aboveAnswer: B Difficulty: ModerateRationale: / - 1 = %44. What is the yield to maturity on a 3-year zero coupon bond?A) %B) %C) %D) %E) none of the aboveAnswer: D Difficulty: ModerateRationale: (1000 / 1/3 -1 = %45. What is the price of a 4-year maturity bond with a 10% coupon rate paid annually? (Parvalue = $1,000)A) $B) $1,C) $1,D) $1,E) none of the aboveAnswer: C Difficulty: DifficultRationale: (1000 / 1/4 -1 = %; FV = 1000, PMT = 100, n = 4, i = , PV = $1,46. You have purchased a 4-year maturity bond with a 9% coupon rate paid annually. Thebond has a par value of $1,000. What would the price of the bond be one year from now if the implied forward rates stay the same?A) $B) $1,C) $1,D) $1,E) none of the aboveAnswer: A Difficulty: DifficultRationale: / ]1/3 - = %; FV = 1000, PMT = 90, n = 3, i = , PV = $Use the following to answer question 47:47. Given the bond described above, if interest were paid semi-annually (rather thanannually), and the bond continued to be priced at $, the resulting effective annual yield to maturity would be:A) Less than 10%B) More than 10%C) 10%D) Cannot be determinedE) None of the aboveAnswer: B Difficulty: ModerateRationale: FV = 1000, PV = , PMT = 45, n = 36, i = (semi-annual); 2 - 1 = %.Use the following to answer questions 48-50:48. What should the purchase price of a 2-year zero coupon bond be if it is purchased at thebeginning of year 2 and has face value of $1,000?A) $B) $C) $D) $E) $Answer: D Difficulty: DifficultRationale: $1,000 / [] = $49. What would the yield to maturity be on a four-year zero coupon bond purchased today?A) %B) %C) %D) %E) none of the above.Answer: A Difficulty: ModerateRationale: [ ]1/4 - 1 = %50. Calculate the price at the beginning of year 1 of an 8% annual coupon bond with facevalue $1,000 and 5 years to maturity.A) $1,B) $1,C) $1,D) $1,E) $Answer: C Difficulty: DifficultRationale: i = [ ]1/5 - 1 = 6%; FV = 1000, PMT = 80, n = 5, i = 6, PV = $51. Given the yield on a 3 year zero-coupon bond is 7% and forward rates of 6% in year 1and % in year 2, what must be the forward rate in year 3?A) %B) %C) %D) %E) none of the above.Answer: C Difficulty: ModerateRationale: f3 = 3 / [ ] - 1 = %Use the following to answer questions 52-61:52. What should the purchase price of a 1-year zero coupon bond be if it is purchased todayand has face value of $1,000?A) $B) $C) $D) $E) $Answer: D Difficulty: DifficultRationale: $1,000 / = $53. What should the purchase price of a 2-year zero coupon bond be if it is purchased todayand has face value of $1,000?A) $B) $C) $D) $E) $Answer: B Difficulty: DifficultRationale: $1,000 / [] = $54. What should the purchase price of a 3-year zero coupon bond be if it is purchased todayand has face value of $1,000?A) $B) $C) $D) $E) $Answer: E Difficulty: DifficultRationale: $1,000 / [] = $55. What should the purchase price of a 4-year zero coupon bond be if it is purchased todayand has face value of $1,000?A) $B) $C) $D) $E) $Answer: B Difficulty: DifficultRationale: $1,000 / [] = $56. What should the purchase price of a 5-year zero coupon bond be if it is purchased todayand has face value of $1,000?A) $B) $C) $D) $E) $Answer: A Difficulty: DifficultRationale: $1,000 / [] = $57. What is the yield to maturity of a 1-year bond?A) %B) %C) %D) %E) %Answer: A Difficulty: ModerateRationale: % (given in table)58. What is the yield to maturity of a 5-year bond?A) %B) %C) %D) %E) %Answer: C Difficulty: ModerateRationale: []1/5 -1 = %59. What is the yield to maturity of a 4-year bond?A) %B) %C) %D) %E) %Answer: C Difficulty: ModerateRationale: []1/4 -1 = %60. What is the yield to maturity of a 3-year bond?A) %B) %C) %D) %E) %Answer: B Difficulty: ModerateRationale: []1/3 -1 = %61. What is the yield to maturity of a 2-year bond?A) %B) %C) %D) %E) %Answer: D Difficulty: ModerateRationale: []1/2 -1 = %Essay Questions62. Discuss the three theories of the term structure of interest rates. Include in yourdiscussion the differences in the theories, and the advantages/disadvantages of each.Difficulty: ModerateAnswer:The expectations hypothesis is the most commonly accepted theory of term structure.The theory states that the forward rate equals the market consensus expectation of future short-term rates. Thus, yield to maturity is determined solely by current and expected future one-period interest rates. An upward sloping, or normal, yield curve wouldindicate that investors anticipate an increase in interest rates. An inverted, or downward sloping, yield curve would indicate an expectation of decreased interest rates. Ahorizontal yield curve would indicate an expectation of no interest rate changes.The liquidity preference theory of term structure maintains that short-term investorsdominate the market; thus, in general, the forward rate exceeds the expected short-term rate. In other words, investors prefer to be liquid to illiquid, all else equal, and willdemand a liquidity premium in order to go long term. Thus, liquidity preference readily explains the upward sloping, or normal, yield curve. However, liquidity preferencedoes not readily explain other yield curve shapes.Market segmentation and preferred habitat theories indicate that the markets fordifferent maturity debt instruments are segmented. Market segmentation maintains that the rates for the different maturities are determined by the intersection of the supply and demand curves for the different maturity instruments. Market segmentation readilyexplains all shapes of yield curves. However, market segmentation is not observed in the real world. Investors and issuers will leave their preferred maturity habitats if yields are attractive enough on other maturities.The purpose of this question is to ascertain that students understand the variousexplanations (and deficiencies of these explanations) of term structure.63. Term structure of interest rates is the relationship between what variables? What isassumed about other variables? How is term structure of interest rates depictedgraphically?Difficulty: ModerateAnswer:Term structure of interest rates is the relationship between yield to maturity and term to maturity, all else equal. The "all else equal" refers to risk class. Term structure ofinterest rates is depicted graphically by the yield curve, which is usually a graph of .governments of different yields and different terms to maturity. The use of .governments allows one to examine the relationship between yield and maturity,holding risk constant. The yield curve depicts this relationship at one point in time only.This question is designed to ascertain that students understand the relationshipsinvolved in term structure, the restrictions on the relationships, and how therelationships are depicted graphically.64. Although the expectations of increases in future interest rates can result in an upwardsloping yield curve; an upward sloping yield curve does not in and of itself imply the expectations of higher future interest rates. Explain.Difficulty: ModerateAnswer:The effects of possible liquidity premiums confound any simple attempt to extractexpectation from the term structure. That is, the upward sloping yield curve may be due to expectations of interest rate increases, or due to the requirement of a liquiditypremium, or both. The liquidity premium could more than offset expectations ofdecreased interest rates, and an upward sloping yield would result.The purpose of this question is to assure that the student understands the confounding of the liquidity premium with the expectations hypothesis, and that the interpretations of term structure are not clear-cut.65. Explain what the following terms mean: spot rate, short rate, and forward rate. Whichof these is (are) observable today?Difficulty: ModerateAnswer:From the answer to Concept Check 2, on page 516: “The n-period spot rate is the yield to maturity on a zero-coupon bond with a maturity of n periods. The short rate forperiod n is the one-period interest rate that will prevail in period n. The forward rate for period n is the short rate th at would satisfy a “break-even condition” equating the total returns on two n-period investment strategies. The first strategy is an investment in an n-period zero-coupon bond. The second is an investment in an n-1 period zero-coupon bond “rolled over” i nto an investment in a one-period zero. Spot rates and forward rates are observable today, but because interest rates evolve with uncertainty, future short rates are not. In the special case in which there is no uncertainty in future interest rates, the forward rate calculated from the yield curve would equal the short rate that will prevail in that period.”This question checks whether the student understands the difference between each kind of rate.66. Answer the following questions that relate to bonds.• A 2-year zero-coupon bond is selling for $. What is the yield to maturity of this bond?•The price of a 1-year zero coupon bond is $. What is the yield to maturity of this bond?•Calculate the forward rate for the second year.•How can you construct a synthetic one-year forward loan (you are agreeing now to loan in one year)? State the strategy and show the corresponding cash flows.Assume that you can purchase and sell fractional portions of bonds. Show allcalculations and discuss the meaning of the transactions.Difficulty: Difficult。

2.Colonial America(殖民时期的美国文学)

全堕落mited atonement (有限
救赎，只有被上帝选中的人才能得到上帝的拯救)
Puritans’ clothing
II. American Puritanism
Features of American Puritan
idealist dream
• The first writings that we call American were the narratives and journals of the settlement.
Colonial America
I. Historical Background II. American Puritanism III. General Features IV. Literature of
William Bradford
• Of Plymouth Plantation Records 《普利茅斯种植园史》
• A masterful account of the separatist colony, the second permanent English settlement in Plymouth.
Puritans
advocated religious & moral principles
a group of religious people
I. Historical Background
Calvinists
a code of values a philosophy of life a point of view
Jamestown Colony
John Smith
I. Historical Background
2. People: native inhabitants: Indians Immigrants mostly from Europe: Spanish; Dutch;

尊重自然法则的英语作文

Respecting the laws of nature is an essential aspect of our existence on this planet. The natural world operates on a set of intricate and delicate balances that have been finetuned over millions of years.As humans,it is our responsibility to understand and respect these laws to ensure the sustainability of our environment and the wellbeing of all living creatures.Firstly,the law of conservation of energy is a fundamental principle that states energy cannot be created or destroyed,only transformed.This concept applies to our use of natural resources,such as fossil fuels,which release energy when burned but contribute to climate change.By respecting this law,we can focus on developing renewable energy sources like solar,wind,and hydroelectric power,which have a lower environmental impact.Secondly,the law of interdependence highlights the interconnectedness of all life forms within an ecosystem.Every organism plays a role in maintaining the balance of its environment.For example,bees are essential for pollination,which in turn supports plant growth and food production.By respecting this law,we can promote biodiversity and avoid the overuse of pesticides that can harm these vital pollinators.Thirdly,the law of adaptation emphasizes the importance of species evolving to survive in their environment.This process can be disrupted by human activities such as deforestation and pollution,which can lead to the loss of habitats and the extinction of species.Respecting this law means preserving natural habitats and minimizing our impact on the ecosystems we share with other species.Furthermore,the law of cause and effect reminds us that our actions have consequences. For instance,the excessive use of water can lead to droughts and water scarcity,affecting both human populations and wildlife.By respecting this law,we can implement sustainable water management practices and promote water conservation.Lastly,the law of limits teaches us that there are finite resources on our planet. Overconsumption and wasteful practices can deplete these resources,leading to environmental degradation and scarcity.Respecting this law involves adopting a more sustainable lifestyle,reducing waste,and promoting recycling and reuse.In conclusion,respecting the laws of nature is crucial for the preservation of our planet and the survival of all species.By understanding and adhering to these principles,we can work towards a more sustainable future and ensure the health of our environment for generations to come.。

我们要怎么驯服牛英语作文

我们要怎么驯服牛英语作文How to Tame a CowTaming a cow is not an easy task, but it can be done with patience and the right approach. Here are some steps to help you tame a cow.First of all, it's important to build trust with the cow. Spend time around it, approach it slowly and calmly, and avoid making sudden movements or loud noises that might startle it. Offer it food, such as fresh hay or grns, to associate your presence with something positive.Next, start handling the cow gently. Begin touching its back or sides softly, gradually increasing the duration and intensity of the contact. This helps the cow get used to your touch and bees more fortable with your presence.When leading the cow, use a gentle and consistent pressure. A halter and lead rope can be helpful, but make sure it fits properly and doesn't cause disfort. Use verbal cues in a soft and soothing tone to guide the cow's movements.Trning sessions should be short and frequent to avoid overwhelming the cow. Reward it with treats or prse when it responds positively to your mands or behaves as desired.It's also crucial to provide a safe and fortable environment for the cow. A clean and well-mntned enclosure, along with access to fresh water and proper shelter, will contribute to its sense of security and well-being.Remember, taming a cow takes time and effort. Each cow has its own personality, so the process may vary. But with kindness, consistency, and understanding, you can successfully tame a cow and establish a positive relationship with it.。

GR63标准讲解

temperature controlled environments
6 Sycamore Networks Company Confidential
Transportation and Handling Required tests
• GR-63-CORE
— Transportation Vibration-sine — Packaged drop — Un-packaged drop
Central Office Environment
• GR-63-CORE
24 Sycamore Networks Company Confidential
Operational Tests Setup
• Unit must be
configured to produce maximum heat load.
GR-63-CORE Altitude GR-63-
28 Sycamore Networks Company Confidential
Fire Resistance
• GR-63-CORE
— Setup requires a fully loaded chassis — Methane line burner replaces one circuit card — Smoke and gasses are analyzed for concentration of:
4 Sycamore Networks Company Confidential
Disasters
• Earthquakes • Fires
5 Sycamore Networks Company Confidential
Assumptions

英语事业单位试题及答案

英语事业单位试题及答案一、选择题（每题2分，共20分）1. Which of the following is NOT a fruit?A. AppleB. TomatoC. CarrotD. Banana2. The phrase "break the ice" means:A. To stop the ice from meltingB. To start a conversationC. To make the ice thickerD. To cool down a room3. The past tense of "begin" is:A. BeganB. BegunC. BegotD. Begging4. In the sentence "She is a _______ of her father's success," the correct word to fill in the blank is:A. beneficiaryB. participantC. spectatorD. contributor5. The expression "cost an arm and a leg" is used to describesomething that:A. Is very cheapB. Is very expensiveC. Has many partsD. Is very heavy6. The word "alibi" is used to describe:A. A place of interestB. An excuse for not being presentC. A legal documentD. A type of food7. The opposite of "agree" is:A. DisagreeB. AgreeC. LikeD. Prefer8. The word "pioneer" is most closely related to:A. A beginnerB. A followerC. A leaderD. A spectator9. The verb "to adapt" means:A. To addB. To changeC. To copyD. To remove10. The phrase "hit the books" is a slang term for:A. To play sportsB. To study hardC. To hit someoneD. To read for fun二、填空题（每题1分，共10分）11. The word "____" means "to make something more suitable for a particular purpose."Answer: modify12. "____" is the term used for a person who is very careful with money.Answer: miser13. "____" is the past participle of "lose."Answer: lost14. The phrase "____" is used to express that something is very easy.Answer: a piece of cake15. "____" is the term for a person who is skilled in many areas.Answer: polymath16. The word "____" is used to describe a person who is very talkative.Answer: chatterbox17. "____" is the term for a person who is always ready to help others.Answer: Samaritan18. The word "____" means "to make something more attractive or interesting."Answer: embellish19. "____" is the term for a person who is very cautious and careful.Answer: prudent20. The phrase "____" is used to describe a situation where something is done without much thought.Answer: on the spur of the moment三、阅读理解（每题2分，共20分）Read the following passage and answer the questions.Passage:In recent years, the use of renewable energy sources has become increasingly popular. Solar panels, wind turbines, and hydroelectric power plants are all examples of renewable energy technologies. These technologies harness energy from the sun, wind, and water, respectively. Renewable energy is considered environmentally friendly because it produceslittle to no greenhouse gas emissions. Moreover, renewable energy sources are sustainable, meaning they will not run out as long as the sun continues to shine, the wind continues to blow, and the water continues to flow.Questions:21. What are the examples of renewable energy technologiesmentioned in the passage?Answer: Solar panels, wind turbines, and hydroelectric power plants.22. From which natural elements do these technologies harness energy?Answer: The sun, wind, and water.23. Why is renewable energy considered environmentally friendly?Answer: It produces little to no greenhouse gas emissions.24. What does the term "sustainable" mean in the context ofthe passage?Answer: They will not run out as long as the natural elements continue to exist.25. What is the main idea of the passage?Answer: The increasing popularity and benefits of renewable energy sources.四、翻译题（每题5分，共10分）26. 将下列句子从英文翻译成中文。

疼痛与抑郁共病的炎症机制

疼痛与抑郁共病的炎症机制覃加敏;陆永经(综述);蔡伦(审校)【摘要】疼痛与抑郁共病在一些内科疾病患者身上很常见。

经研究发现炎症是抑郁与疼痛共病的可能机制。

这些机制包括细胞因子对神经元环境发挥直接作用与下调G蛋白耦联受体激酶2，激活色氨酸代谢酶（吲哚2，3-双加氧酶）产生有毒的犬尿素代谢产物而发挥间接作用。

文中就疼痛与抑郁共病的炎症机制作一综述。

%Comorbid depression and chronic pain are highly prevalent in individuals suffering from physical illness .Here, we critically examine that inflammation is the possible mechanism of comorbidity of pain and depression .These mechanisms include direct effects of cytokines on the neuronal environment or indirect effects via downregulation of G protein -coupled receptor kinase 2, activation of the tryptophan-degrading enzyme indoleamine 2,3-dioxygenase that generates toxic kynurenine metabolites .We review the role of in-flammation in the mechanism of the commorbidity of depression and pain .【期刊名称】《医学研究生学报》【年(卷),期】2015(000)008【总页数】4页(P893-896)【关键词】疼痛;抑郁;炎症【作者】覃加敏;陆永经(综述);蔡伦(审校)【作者单位】545002 柳州，广西柳州柳钢医院麻醉科;530001南宁，广西民族医院内科;530023 南宁，广西中医药大学第一附属医院神经内科【正文语种】中文【中图分类】R749.40 引言炎症过程是疼痛、抑郁的重要原因，持续的慢性炎症过程导致不断的疼痛和难以治愈的抑郁。

莫西沙星短程疗法治疗慢性阻塞性肺疾病急性加重期的疗效分析

莫西沙星短程疗法治疗慢性阻塞性肺疾病急性加重期的疗效分析陆徐峰;王静;胡志雄;周海英【摘要】目的比较莫西沙星短程及标准疗程对慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)急性加重期(acute exacerbation of COPD,AECOPD)的疗效.方法选择门诊的稳定期COPD患者在发生急性加重时随机进入莫西沙星短程治疗组(n=43)及标准治疗组(n=43).两组均采用莫西沙星每日口服400mg,试验组疗程为5天,对照组疗程为10天,疗程结束后继续随访6个月.对两组患者的临床疗效、细菌清除率、1秒用力呼气容积(forced expiratory volume in one second,FEV1)下降值及6个月内急性加重发生次数进行观察和比较.结果短程治疗组的临床效率、细菌清除率、FEV1下降值、6个月内急性加重发生次数及急性加重间隔时间与标准治疗组相似,差异无显著统计学意义(P＞0.05).结论口服莫西沙星短程疗法对AECOPD具有良好的治疗效果.%Objective To compare the effectiveness of moxifloxacin short-course therapy with standard-course therapy in acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods Outpatients with COPD during acute exacerbation in a stable condition were enrolled and randomized into moxifloxacin short-course group (n = 43,400 mg qd for 5 days) and standard-course group (n = 43,400 mg qd for 10 days). All patients were visited for 6 months after the therapy. We observed and compared the efficacy parameters including dinical efficacy,bacterial eradicationrate,forced expiratory volume in one second (FEV1) and the frequency of exacerbation in the next 6 months. Results Clinical efficacy, bacterialeradication rate FEVl and the frequency of exacerbation in the next 6 months were similar for the two groups (P>0.05). Conclusions Short-course treatment of moxifloxacin taken orally is effective in the therapy of AECOPD.【期刊名称】《复旦学报（医学版）》【年(卷),期】2011(038)006【总页数】4页(P534-537)【关键词】莫西沙星;短程疗法;慢性阻塞性肺疾病;急性加重期【作者】陆徐峰;王静;胡志雄;周海英【作者单位】复旦大学附属中山医院呼吸科上海200032;复旦大学附属金山医院呼吸内科上海200540;复旦大学附属金山医院呼吸内科上海200540;复旦大学附属金山医院呼吸内科上海200540;复旦大学附属金山医院呼吸内科上海200540【正文语种】中文【中图分类】R563.5慢性阻塞性肺疾病（chronic obstructive pul monary disease，COPD）是一种具有气流受限特征的疾病，气流受限不完全可逆、呈进行性发展，其病程可分为急性加重期（acute exacer bation of COPD，AECOPD）与稳定期。

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a r X i v :0705.1705v 1 [a s t r o -p h ] 11 M a y 2007Mon.Not.R.Astron.Soc.000,1–??(2007)Printed 1February 2008(MN L A T E X style ﬁle v2.2)On the nature of the short duration GRB 050906A.J.Levan 1⋆,N.R.Tanvir 2,P.Jakobsson 3,4,R.Chapman 3,J.Hjorth 4,R.S.Priddey 3,J.P.U Fynbo 4,K.Hurley 5,B.L.Jensen 4,R.Johnson 6,J.Gorosabel 7,A.J.Castro-Tirado 7,M.Jarvis 3,D.Watson 4,K.Wiersema 81Department of Physics,University of Warwick,Coventry,CV47AL,UK2Departmentof Physics and Astronomy,University of Leicester,Leicester,LE17RH,UK3Centre for Astrophysics Research,University of Hertfordshire,College Lane,Hatﬁeld,AL109AB,UK4Dark Cosmology Centre,Niels Bohr Institute,University of Copenhagen,Juliane Maries Vej 30,DK-2100Copenhagen,Denmark 5Oxford Astrophysics,Department of Physics,University of Oxford,Keble Road,Oxford,OX13RH,UK 6University of California at Berkeley,Space Sciences Laboratory,CA 94720-74507Instituto de Astroﬁsica de Andalucia,18008Granada,Spain8Astronomical Instituut ”Anton Pannekoek”,Kruislaan 403,1098SJ Amsterdam,NLAccepted 2007May 08.Received 2007May 03;in original form 2007March 12ABSTRACTWe present deep optical and infrared observations of the short duration GRB 050906.Although no X-ray or optical/IR afterglow was discovered to deep limits,the error circle of the GRB (as derived from the Swift BAT)is unusual in containing the rela-tively local starburst galaxy IC328.This makes GRB 050906a candidate burst from a soft-gamma repeater,similar to the giant ﬂare from SGR 1806-20.The probability ofchance alignment of a given BAT position with such a galaxy is small (∼<1%),althoughthe size of the error circle (2.6arcminute radius)is such that a higher z origin can’t be ruled out.Indeed,the error circle also includes a moderately rich galaxy cluster at z =0.43,which is a plausible location for the burst given the apparent preference that short GRBs have for regions of high mass density.No residual optical or infrared emission has been observed,either in the form of an afterglow or later time emission from any associated supernova-like event.We discuss the constraints these limits place on the progenitor of GRB 050906based on the expected optical signatures from both SGRs and merging compact object systems.Key words:Gamma-ray bursts:1INTRODUCTIONUntil recently the revolution of our knowledge of gamma-ray burst (GRB)sources was limited almost exclusively to those with durations of t 90>2s –so called long bursts (see e.g Meszaros 2006for a review).The discovery of after-glows of the long duration bursts enabled rapid progress by allowing the identiﬁcation of redshifts (e.g.Metzger et al.1997),star forming host galaxies (e.g.Conselice et al.2005;Wainwright et al.2005;Fruchter et al.2006)and ultimately unambiguous supernova signatures (eg.Hjorth et al.2003)–ﬁnally linking long-duration GRBs to the collapse of massive stars.Afterglows of the short-duration GRBs (S-GRBs)have⋆email:a.j.levan@,Based on observations made with ESO telescopes at the Paranal Observatory under pro-gramme ID 075.D-0261still only been discovered for relatively few bursts (e.g.Gehrels et al.2005;Bloom et al.2005;Hjorth et al.2005a,Fox et al.2005;Berger et al.2005;Soderberg et al.2006;Levan et al.2006a;Levan &Hjorth 2006).Nonetheless the afterglows (e.g.Hjorth et al.2005a;Fox et al.2005;Burrows et al.2006;Grupe et al.2006;Campana et al.2006),and the host galaxies which they select (e.g Gal-Yam et al.2005;Barthelmy et al.2005;Prochaska et al.2005;Gorosabel et al.2006)are apparently diﬀerent,at least on the average,to those of long-duration GRBs.Short GRBs seem to occur in galaxies of all types including those with a older stel-lar populations,although the statistical signiﬁcance of such associations is often fairly low (see e.g.Bloom et al.2007;Levan et al.2007).S-GRBs are typically located at larger distances from their host galaxy nuclei and are also less lumi-nous and at a lower mean redshift than long-duration bursts (cf.Jakobsson et al.2006),although at least one short-burst (GRB 060121;Levan et al.2006a;de Ugarte Postigo et al.c2007RAS2 A.J.Levan et al.2006)apparently originates from signiﬁcantly higher red-shift,and may point to the existence of a larger population of high redshift S-GRBs.These properties can naturally be explained as being due to the merger of a tight binary con-sisting of compact objects(neutron stars(NS)or black holes (BH))following energy and angular momentum dissipation via gravitational radiation(eg.Rosswog&Ramirez-Ruiz 2003;Rosswog,Ramirez-Ruiz&Davies2003;Davies,Levan &King2005),although this is by no means the only viable mechanism.However,while the properties described above are al-ready diverse they may well not represent the whole S-GRB population.The discovery of a massiveﬂare from soft gamma-ray repeater(SGR)1806-20(Hurley et al.2005; Palmer et al.2005)provided evidence that some fraction of the large sample of S-GRBs found by the Burst And Tran-sient Source Experiment(BATSE)could be explained by SGR giant-ﬂares in galaxies out to∼30−40Mpc,and potentially further with Swift.Furthermore a correlation of short bursts detected by BATSE with galaxies within the lo-cal universe(<100Mpc)reveals that a fraction(between10-25%)of short bursts originate from this nearby large-scale structure(Tanvir et al.2005).Plausible(but broad)lumi-nosity functions can accommodate both a moderate fraction of bursts in the local universe and a signiﬁcant fraction at z>0.2(Nakar et al.2006)even if they are from a single class of progenitor.Perhaps rather more likely is that two populations of short-bursts are being observed,those from SGR giantﬂares,and those due to other events,most likely NS-NS or NS-BH mergers.To date it has not been possible to identify with high conﬁdence the individual host galaxies of short bursts which may be due to SGR giantﬂares,due to the large error re-gions associated with BATSE bursts and the relative dearth of smaller error boxes from eg.the interplanetary network (IPN-Hurley et al.2002).Here we present optical observa-tions of theﬁeld of Swift-discovered GRB050906(Krimm et al.2005).The bright,nearby galaxy IC328lies within its positional error circle and makes a good case for a short GRB associated with an SGR giantﬂare.However,as we show,a higher redshift origin can’t be ruled out,and in par-ticular a bright galaxy cluster at z=0.43also overlaps the error circle and provides a viable alternative origin for the burst.2OBSER V ATIONSGRB050906was detected with the Swift satellite(Gehrels et al.2004)on2005September0610:32UT(day6.4389). The on-board reported location was RA=03h31m13s,Dec =-14◦37′30′′,with a positional accuracy of3′(Krimm et al.2005).As the burst was very faint it was not atﬁrst clear if a real GRB had been observed.However it was pointed out immediately that the error circle of GRB050906was unusual in containing a bright,low-redshift galaxy,IC328 (Levan&Tanvir2005),which is at a redshift of z=0.031,a distance of only≈130Mpc(Assuming a standardΛCDM cosmology withΩM=0.27,ΩΛ=0.73,H0=73km s−1 Mpc−1).A prompt slew was performed to the location of GRB 050906with observations with the X-ray telescope(XRT-Burrows et al.2005)beginning79s after the burst.These observations failed to locate any convincing X-ray afterglow (Pagani et al.2005).Subsequently the BAT localisation of GRB050906was reﬁned to RA=03h31m22s,Dec=-14◦39′00′′,with a2.6arcmin(90%)uncertainty(Parsons et al.2005).Its t90duration was128ms and the totalﬂuence in the15-150keV band was very low at7.0±3.2×10−9 ergs cm−2.No prompt observations were obtained with the UV/Optical telescope(UVOT,Roming et al.2005)since it was in safe mode at the time of the burst.Full details of the Swift observations of GRB050906are described in a separate paper(Hurley et al.in prep),which concludes that the burst would be surprisingly soft if from a SGR giantﬂare.However,since the properties of giantﬂares are rather poorly understood,it remains important to look at the other evidence for and against such an explanation in this particular case.Weﬁrst observed the error circle of GRB050906using the Wide Field Camera(WFCAM)on the United Kingdom Infrared Telescope(UKIRT)beginning at Sept6.51(UT), 1.7hours after the burst(a complete log is shown in Table 1).A K-band integration of40minutes was made.A sec-ond,similar exposure was obtained the following night(∼26hours after the burst).Deep optical observations were ac-quired at the ESO Very Large Telescope(VLT),covering the VRI bands(∼1800s in each band).Three epochs of observa-tions were obtained using the FORS1and FORS2imagers at21and140hours and18days after the burst.We also obtained deep,late time IR observations using VLT/ISAAC in J,H and K.Optical observations were processed through IRAF in the standard fashion.The UKIRT/WFCAM ob-servations were reduced via the ORAC-DR pipeline(Ca-vanagh et al.2003)and the VLT/ISAAC observations were processed with eclipse(Devillard1997).Cameron&Frail(2005)identiﬁed a single radio source within the initial burst error circle(although outside the reﬁned BAT source location),the position of this source is RA=03h31m11.8s,Dec=-14◦37′18.1′′.At this location our images reveal a very red point source(R−K=5.6). However,it did not exhibit any variability in the optical or IR and it is likely to be a background galaxy.Although the prompt XRT X-ray observations failed to locate any strong candidate for the afterglow of the burst,an inspection of the images did produce a possible faint coun-terpart(Fox et al.2005;Butler2006).However,its associ-ation with GRB050906,and even its reality remain highly uncertain.The reﬁned location of this candidate is RA= 03h31m15.28s,Dec=-14◦36′13.1′′.Weﬁnd no evidence for any variable point sources within this region,nor for any particular overdensity of galaxies within the large(15.7′′radius)localisation.A detailed inspection of the entire error region within our observations revealed no evidence for new sources by comparison to archival surveys,or between our own images taken at diﬀerent epochs.We estimate the limiting magni-tude of each individual frame by examining the signal-to-noise ratios for the photometry of many point sources:the resulting limiting magnitudes are shown in Table1.In order to search for a variable afterglow(which may be placed on top of a relatively bright host galaxy)we performed PSF-matched image subtractions of the diﬀerent epochs of imag-ing using the code of Alard&Lupton(1998).Each epochc 2007RAS,MNRAS000,1–??On the nature of the short duration GRB 0509063Figure 1.Finding chart for GRB 050906.North is up and east to the left.The GRB error circle of 5.2′diameter is shown.As can be seen the bright,low-redshift galaxy IC 328lies on the edge of this error circle,which would be an unlikely chance coincidence if it is not associated with the GRB.However,there are many other more distant galaxies clearly seen in the ﬁeld,including a galaxy cluster which,as discussed in the text,is also a viable location of the GRB.Figure 2shows an enlarged region about this cluster and the area shown is marked by the white box.of observations was subtracted from each other epoch ob-tained in the same ﬁlter.These subtractions yielded very clean residual images in the cases of using the same tele-scope and instrument,although larger residuals where ob-servations had to be matched from diﬀerent telescopes.To estimate the limiting magnitude of any variable sources we seeded each image with a number of false stars (which were added with the appropriate PSF for the image in which they are seeded)and then repeated the subtractions.The magni-tude of sources which can be recovered as residuals at >5σin the resulting diﬀerence images are also shown in Table 1.As the error circle of GRB 050906contains the bright nearby galaxy IC 328(and the companion galaxy IC 327is just outside the error circle)we separately estimate the lim-iting magnitude for any variable source within the galaxy.These limits are lower than for the ﬁeld in general since the bright cores of each galaxy leave large residuals in the sub-tracted images.Any source within 5′′of the centre of either galaxy would have to be R <20in order to be detected clearly in our residual images.Although this is relatively bright it should be noted that even a moderately faint su-pernova in IC 328(e.g.one with M V ∼−17at maximum),if unextinguished,would reach a peak about 2.5magnitudes brighter than this.In addition to IC 328and IC 327,visual inspection of our FORS images of GRB 050906revealed many more distant galaxies,including an overdensity of galaxies in the south west of the error circle.Although this clustering ex-tended both beyond the error circle and further beyond the ﬁeld of view of our FORS observations,we estimate that the greatest concentration lies at roughly RA =03h 31mFigure 2.A z =0.43cluster lying within the error circle of GRB 050906.The two galaxies marked A &B have spectroscopic redshifts,while the other galaxies exhibit similar colours and are likely to lie within the same cluster.17s ,Dec =-14◦41′25′′,although the distribution of galax-ies is not uniform and exhibits at least two (possibly more)regions of overdensity (see Figure 2).We obtained spectroscopy of two galaxies from this con-centration using Gemini South and GMOS on 2006January 26,with the G300V grating.The galaxies in question are marked in Figures 1&2.Spectra were reduced in the stan-dard fashion using the speciﬁc GMOS scripts within IRAF.Inspection of these spectra reveals strong absorption fea-tures which we attribute to Ca H &K,and H δat a redshift of z =0.43.3THE PROPERTIES OF IC 328IC 328is a bright K=11.4galaxy and its colours,and some-what disturbed morphology,are consistent with an actively star forming,late-type galaxy.Its observed B-band mag-nitude (B 0=14.9,M B =-20.7)is approximately L*and its R-K colour of ≈2.3is very blue,also indicative of ongo-ing star formation.IC 328was detected by IRAS in all four bands (10,25,60,100µm ).Converting from the observed 60µm ﬂux to a star formation rate assuming a relation of SF R =5.5∗(L 60/5.1×1030ergs /s /Hz)(Kennicutt 1998)results in a star formation rate for IC 328of ∼17M ⊙yr −1.Figure 3shows the SED of IC 328(see also Table 2)over-layed with several comparison spectra (standard Sc,M51and M82).An alternative means of estimating the star for-mation rates is to scale these template spectra such that they provide a reasonable ﬁt to the observed spectral en-ergy distribution of IC 328.Doing this with M51yields a star formation rate of ∼3M ⊙yr −1,signiﬁcantly lower than via the 60µm ﬂux,but consistent with the idea that much of the star formation in IC 328is dust-obscured,leading to the high fIR ﬂuxes.SGRs are commonly thought to be formed via the core-c2007RAS,MNRAS 000,1–??4 A.J.Levan et al.2005Sept6.5020.062160WFCAM/K20.219.5(WFCAM)2005Sept7.3330.891800FORS2/R26.625.9(FORS2)2005Sept7.3450.911800FORS2/V27.326.6(FORS2)2005Sept7.36700.931920FORS2/I25.224.5(FORS2)2005Sept7.510 1.693240WFCAM/K20.419.5(WFCAM)2005Sept12.333 5.891800FORS2/R26.425.9(FORS2)2005Sept12.344 5.901800FORS2/V27.126.6(FORS2)2005Sept12.357 5.921920FORS2/I25.026.6(FORS2)2005Sept25.27218.831800FORS1/R26.225.2(FORS2)2005Sept25.28018.841800FORS1/V26.525.7(FORS2)2005Sept25.29318.851800FORS1/I24.924.2(FORS2)2005Sept29.29422.86320ISAAC/K22.119.5(WFCAM)2005Sept29.34022.90280ISAAC/J23.1-2005Sept29.34622.91208ISAAC/H22.2-Filter IC328IC327referencesTable2.Optical/Infrared observations of IC328and IC327obtained from the literature as cited and via our VLT observations.The optical/nIR photometry has been corrected for foreground extinction following Schlegel et al.(1998).collapse of massive stars and thus would trace the star for-mation rate of a given galaxy,although they may also be produced via accretion induced collapse(AIC)of merging white dwarfs(Usov1992;Levan et al.2006b)and SGRs formed via this channel should trace the stellar mass den-sity.The IR luminosity of IC328implies that it is moder-ately massive:using the stellar mass estimation scheme of Mannucci et al.(2005)yields M∼1011M⊙.Thus IC328 appears in terms of mass to be similar to the Milky Way,and in terms of star formation rather more active than the MW by factors of several,and hence can be expected to harbour at least a similar number of SGRs.If originating from IC328the isotropic equivalent en-ergy of GRB050906would be E iso∼1.5×1046ergs in the 15-150keV range.This compares to a total energy release (>30keV)of E iso∼4×1046ergs for the giantﬂare from SGR1806-20(Hurley et al.2005).Galaxies such as IC328are rare in GRB error circles only a few arcminutes in diameter.To estimate the prob-ability of a chance alignment we simulated a large set of GRB positions placed randomly on the sky and subsequently searched for galaxies within3arcminutes of these positions (our galaxy catalogue was the complete IRAS PSCz cata-logue,which contains IC328and is thus a good catalogue to search for similar galaxies).In a total of50,000random bursts only135matches were found,allowing for the15% avoidance of the Galactic plane in the PSCz survey this im-plies a probability of selecting IR-bright galaxies such as IC328of only0.003.There are,of course,alternative ways this probability analysis could have been performed,for in-stance using optically selected galaxy catalogues.However we feel that our approach is suitably conservative(eg.we might have cut the PSCz sample to galaxies as bright as IC328or brighter),and therefore gives a useful indication of the low likelihood of a chance coincidence.We emphasise that this probability should not simply be regarded as an a posteriori calculation.Tanvir et al.(2005) had already predicted that a non-negligible proportion of short-duration bursts should be associated with low-redshift galaxies,so it is statistically reasonable,therefore,to specif-ically test the null-hypothesis that there is no such associ-ation.At the time of writing roughly a dozen short burstsc 2007RAS,MNRAS000,1–??On the nature of the short duration GRB 0509065Figure 3.The spectral energy distribution of IC 328.Overlayed with template spectra for an Sc galaxy (solid line),M51(dashed line)and M82(dotted line).The spectra have been normalised to the R-band ﬂux.Extrapolating from the M51template we thus obtain a star formation rate of 3M ⊙yr −1,somewhat lower than that that inferred from the 60µm ﬂux.have been observed by Swift ,and a similar number previ-ously well-localised by IPN and HETE-2/BeppoSAX (al-though those detected by the IPN have a signiﬁcantly dif-ferent selection function so comparing their properties with HETE-2/SXC and Swift bursts is non-trivial).In any event,based on our analysis above,we can say with some conﬁ-dence that the probability of a chance occurence of such a nearby and bright galaxy as IC 328in one or more of the HETE-2/SXC and Swift /BAT burst error regions is less than 10%.Further,although none of the other short bursts de-tected by Swift have plausible local hosts,the IPN has de-livered locations for two S-GRBs that may originate in very local galaxies.Firstly GRB 051103has an error box which overlaps the outskirts of both M81and M82(Fredericks et al.2006;Ofek et al.2006),while the recent GRB 070201has an error box which intersects the spiral arms of M31(Golenetskii et al.2007;Hurley et al.2007).These locations lend support to the results of Tanvir et al.(2005)that a frac-tion of short bursts should originate in the local universe,and give further credence to the suggestion that IC 328is the host galaxy of GRB 050906.However,it is also important to ask what is the prob-ability of ﬁnding IC 328at the position we do in the error circle if it is truly associated with the burst.Formally,only a small fraction of IC 328lies within the reﬁned BAT error cir-cle,which,although nominally 90%conﬁdence,are typically conservative (Fenimore,private communication),although this may not be the case for the very short and faint GRB 050906.To gauge the number of bursts which we might ex-pect tolie >2.5′from the BAT localisation we have plotted in Figure 4the oﬀset distribution between XRT and BAT positions for all bursts exhibiting afterglows to the XRT in the ﬁrst year of full Swift operations.This shows that,in fact,90%of the bursts occur within 110′′of the BAT locali-sation,and thus,even faint bursts like GRB 050906should rarely (∼2%of bursts)be at the radial separation of IC 328from the centre of the BAT error circle.Hence,while the association of GRB 050906with IC 328remains plausible,Figure 4.The oﬀset distribution between the reﬁned BAT lo-calisations and the positions of the X-ray afterglows of GRBs detected by Swift .GRBs have been plotted for the period of one full year of Swift operations,from 1April 2005-30March 2006(94bursts with X-ray afterglow locations).As can be seen the majority of Swift bursts lie relatively close to the reﬁned BAT position.Formally 67%lie within 62′′and 90%lie within 109′′.The probability of locating an afterglow greater than 160′′from the burst position is ∼2%,and is dominated by the two outliers,GRB 060109and GRB 060218.There is perhaps a slight trend towards larger oﬀsets for fainter bursts on the average.and would have been identiﬁed as the host galaxy by variousapproaches (e.g.that of Gal-Yam et al.2006),the location at the edge of the error circle does somewhat weaken the case for an association.Of course,were GRB 050906due to a low-luminosity NS-NS merger event within IC328(or even IC 327)then it may be expected to be at a large distance from its parent galaxy either because it took place in the halo (eg.a globular cluster),or having been ejected outside the main body of the galaxy by a natal supernova kick.A kick of 30kpc (e.g.similar to that inferred for GRB 050509B)would have led to an oﬀset of ∼1′,and could place GRB 050906relatively closer to the BAT localisation.Additionally the error circle contains a number of fainter (but still moderately bright)galaxies whose colours and physical sizes could well associate them with a group containing IC 328and IC 327.Several of these galaxies lie relatively close to the centre of the BAT error box.4OTHER GALAXIES WITHIN THE ERROR CIRCLEIn addition to IC328and the possibly associated galaxies de-scribed above,there are many more fainter galaxies which probably lie at a range of higher redshifts.The most notable structure is a relatively rich galaxy cluster which overlaps the southern part of the error circle,which,as discussed in section 2,is at z =0.43.Some,previously well-localisedc2007RAS,MNRAS 000,1–??6 A.J.Levan et al.short bursts have been found to lie in regions of high mass density(e.g.in elliptical galaxies or cluster environments-Gehrels et al.2005;Pedersen et al.2005;Bloom et al.2006), although the faint,and likely high redshift,host galaxies to GRB060121(Levan et al.2006a;de Ugarte Postigo et al.2006)and GRB060313(Hjorth et al.in prep)indicate this is not necessarily the case and that a signiﬁcant frac-tion of SGRBs may originate at higher redshift(Berger et al.2006a).Thus,it is certainly plausible that GRB050906 originated in this cluster.Its duration of128ms is compa-rable to that of GRB050509B and,at z=0.43,its inferred isotropic energy release would be E iso=(3.2±1.4)×1048 ergs,would also place it along with GRB050509B(t90= 40ms,E iso=1×1048ergs;Gehrels et al.2005)as the intrinsically faintest of the cosmological short GRBs seen to-date.5IMPLICATIONS FOR PROGENITOR MODELSThe leading contenders for the progenitors of short-duration GRBs are those which are the result of compact binary mergers(NS-NS,NS-BH and possibly WD-BH–see e.g. Lee&Ramirez-Ruiz for a review)and those resulting from giantﬂares from soft-gamma-repeaters.Observations of S-GRBs detected by Swift provide some support for the for-mer model,while the giantﬂare from SGR1806-20(Hurley et al.2005;Palmer et al.2005)provided renewed impetus to investigate SGRs as candidate progenitors.In particu-lar these may be responsible for the fraction of S-GRBs in the local universe reported by Tanvir et al.(2005),and for the two subsequently detected IPN bursts which may have originated from M81/82and M31.The most intense spike of the SGR1806-20event would have been detected by BATSE as a short-hard gamma-ray burst had it occured out to about30-40Mpc(Hurley et al.2005;Palmer et al.2005), and it would be positively surprising if some proportion of BATSE S-GRBs were not due to such events occurring in nearby galaxies.Most estimates of the volume average star formation rate in the local universe put it at about0.02 M⊙yr−1Mpc−3(eg.Iglesias-Paramo et al.2006).So in a sphere of radius100Mpc we would expect toﬁnd a total rate of star formation roughly20000times the current rate in the Milky Way.SGRs are thought to be young(and short-lived),highly-magnetised neutron stars,and so their number within a galaxy may reﬂect its star-formation rate(but see Levan et al2006b for a possible route to creating magnetars in old stellar populations via WD-WD mergers).Thus,even if an SGR1806-20-like event were only to occur in the MW on average once every two millenia,∼10per year should oc-cur within this volume.Of course,the SGR1806-20ﬂare itself might not have been quite luminous enough to have been detected to100Mpc,but equally,it is unlikely that this event was at the very peak of the luminosity function, and the rate of lower luminosityﬂares may be greater.We must bear in mind that the observed afterglows of many short-duration GRBs have been relatively faint in comparison to typical long bursts(Hjorth et al.2005a;Fox et al.2005;Berger et al.2005;Soderberg et al.2006;Levan et al.2006).Although some are relatively bright,especially in X-rays(e.g.050724Barthelmy et al.2005,Campana et al.2005;GRB051121Burrows et al.2006and GRB060313 Roming et al.2006),a fraction are very faint or undetected both in the optical(Hjorth et al.2005b;Bloom et al.2006; Castro-Tirado et al.2006)or X-ray(e.g.Mineo et al.2005; Page et al.2006;La Parola et al.2006).Similarly,SGRs ap-pear to produce little optical/IR emission during their giant ﬂares,although constraints are not strong.This is partly due to the Galactic SGRs being in the plane of the Milky Way and hence along dusty lines of sight,which would be less of an issue for an observer oriented more face-on to the Galactic plane.SGR giantﬂares may produce optical emission and in-deed mini-ﬁreball models can accurately represent the radio and X-ray emission following the giantﬂare of SGR1806-20.Being close to the galactic plane provides a consider-able challenge to optical observations,although a candidate faint counterpart to SGR1806-20has been identiﬁed from near-IR K-band observations;Kosugi et al.2005,Israel et al. 2005.However the extrapolation of the expected SGR X-ray ﬂux into the optical waveband and the subsequent extrap-olation out to the distance of IC328falls below the detec-tion limits of our observations,especially given(i)SGRs are likely to be located close to the nucleus of the galaxy where our limits are least constraining,and(ii)we infer a high proportion of star formation in IC328is dust obscured.The SGR scenario is not the only possibility for this burst,since it is plausible that another progenitor system created the GRB either in IC328or a more distant galaxy. Indeed,the error box of GRB050906also appears to con-tain a high redshift cluster,an environment in which several short-duration GRBs have been found(e.g.Pedersen et al. 2005;Gal-Yam et al.2005;Berger et al.2007).We thus can-not rule out a burst originating from a galaxy associated with this cluster and consider below the implications for short bursts located in either IC328or the higher-z cluster.The principle alternative model is that of NS-NS merg-ers.These might also be expected to result in bright though relatively short lived optical emission due to the production of heavy elements during the mergers(e.g.Li&Paczynski 1998)–so called mini-SN or macro-novae(MN).These tran-sients can reach absolute magnitudes comparable to those of SNe,although typically last for a much shorter duration, peaking only a day or so after the merger(although the pre-cise behaviour depends on the nuclear yields in the merger itself which are only poorly understood;but see Rosswog et al.2000).In Figure5we show the limits on any residual emission within the GRB050906error circle.We also over-plot the SN Ic supernova SN2002ap at the distance of IC 328(z=0.03).We do not overplot the predicted magnitudes for any MN emission since the behaviour of such transients is only known from theory as none have been directly observed. However,canonical parameters thought to be associated with NS-NS mergers(e.g.Kulkarni2005)would predict that they would reach peakﬂuxes of∼0.1µJy at z=0.2,or severalµJy(R∼22)when extrapolated to the distance of IC328.The models also predict that they will reach this maximum on a timescale of hours to days past the explosion, and can therefore be searched for in our deep optical imag-ing1,6and19days post burst.Although previous S-GRBs have not shown any sign of MN emission(e.g.Hjorth et al. 2005a,b;Fox et al.2005;Bloom et al.2006),these bursts layc 2007RAS,MNRAS000,1–??。