Phenomenological study of the double radiative decay $B -Kgammagamma$
Linear sigma model at finite temperature
2 is the order of this transition, is it first–order with latent heat, or second–order, or maybe a crossover between the A. The potential at one–loop 27 phases? Lattice calculations suggest that when we consider two massless quarks, the transition is second order B. One loop mass correction 27 and the same suggest other approaches based on effective models. If we consider three massless flavours of quarks, C. The Keldysh contour 28 the transition is probably first–order [3, 6]. The aim of this work is to study the chiral phase transition. D. The pion self–energy graphs 28 1. The pion self–energy graph with one thermal pion28 Chiral symmetry breaking is a necessary ingredient for low energy hadron physics, since unbroken chiral symmetry results in massless baryons, without parity doubled 2. The pion
学术现象英语作文范文
学术现象英语作文范文Title: Academic Phenomena: A Discussion。
Academic phenomena are diverse and multifaceted, reflecting the intricate dynamics within the scholarly community. From groundbreaking discoveries to persistent challenges, these phenomena shape the landscape of knowledge production and dissemination. In this essay, we will explore various academic phenomena and their implications.One notable academic phenomenon is the replication crisis. In recent years, numerous studies across various disciplines have failed to replicate previous findings, raising concerns about the reliability and validity of research outcomes. This phenomenon highlights the importance of rigorous research methods and transparent reporting practices in ensuring the credibility of scientific knowledge.Another significant academic phenomenon is interdisciplinary research. With the increasingly complex nature of contemporary issues, scholars are increasingly collaborating across disciplinary boundaries to address multifaceted challenges. This phenomenon fosters innovation and allows for a more comprehensive understanding of complex phenomena by integrating insights from diverse fields.Moreover, the rise of open access publishing is a notable academic phenomenon. Traditionally, access to scholarly publications has been restricted by paywalls, limiting the dissemination of knowledge. However, the open access movement seeks to make research freely available to the public, thereby democratizing access to information and promoting greater global collaboration among researchers.Academic plagiarism is another prevalent phenomenonthat poses ethical and intellectual challenges within the scholarly community. With the ease of access to digital resources, instances of plagiarism have become more widespread, undermining the integrity of academic research.Addressing this phenomenon requires a concerted effort to promote academic integrity and educate researchers about ethical research practices.Furthermore, the phenomenon of academic inequality persists within the scholarly community, with disparities in resources, opportunities, and representation among different demographic groups. This phenomenon underscores the need for inclusive policies and initiatives to address systemic barriers and promote diversity and equity in academia.Additionally, the phenomenon of citation cartels highlights the complex dynamics of scholarly communication and evaluation. In some cases, researchers may engage in reciprocal citation practices to artificially inflate their citation counts, influencing academic rankings and funding decisions. Addressing this phenomenon requires greater transparency and accountability in citation practices.Overall, academic phenomena encompass a wide range of dynamics and challenges within the scholarly community. Byunderstanding and addressing these phenomena, we can foster a more robust and equitable academic environment conducive to knowledge creation and dissemination.。
科学现象和蕴含的科学知识
科学现象和蕴含的科学知识英文回答:Scientific phenomena are observable events or processes that occur in the natural world. They can be physical, chemical, biological, or geological in nature. The study of scientific phenomena has led to the development of a vast body of scientific knowledge, which includes theories, laws, and principles that explain how the natural world works.Some of the most important scientific phenomena include:The law of gravity: This law states that all objects with mass attract each other with a force proportional to their masses and inversely proportional to the square ofthe distance between them.The laws of thermodynamics: These laws describe the behavior of heat and energy in closed systems.The theory of evolution: This theory explains how species change over time through the process of natural selection.The laws of electromagnetism: These laws describe the interactions between electric and magnetic fields.The quantum theory: This theory describes the behavior of matter at the atomic and subatomic level.These are just a few of the many scientific phenomena that have been studied and explained by scientists. The study of scientific phenomena has led to a greater understanding of the natural world and has made possible many technological advancements, such as the development of computers, airplanes, and medical treatments.中文回答:科学现象是指在自然界中发生的、可观察的事件或过程。
reader-response-theory
• 5 the ideal reader • Proposed by J. Culler • Someone who has possessed , or rather
internalized ,the literary conventions , the mastery of which would enable him to perform literary readings acceptable to other readers, for such conventions constitute the very institution of literature itself.
“horizon of expectations,” “the set of cultural ,ethical, and literary expectations of a work’s readers in the historical moment of its appearance.
7/15/2024
The messenger of the gods
A theory that sees history as a living dialogue between past , present and future ,and seeks patiently to remove obstacles to this endless mutual communication.
7/15ቤተ መጻሕፍቲ ባይዱ2024
The implied reader
• Against these “limitations“,Iser’s concept of the reader stands as a good contrast.
phenomenological study -回复
phenomenological study -回复什么是现象学研究?现象学研究是一种哲学研究方法,旨在描述和解释人类的经验和现实世界的本质。
它关注个体的主观体验和意义,强调经验的真实性和主观性。
现象学研究通过反思、描述和解释人类的直接经验,试图揭示现实世界的本质及其和主体的关系。
在这种研究中,研究者旨在去除预设的概念和解释,直接从经验本身出发,并通过反思和解释来理解个体的意义构建和经验。
现象学研究的方法和步骤:1. 定义研究问题:在进行现象学研究之前,首先需要明确研究的问题和目的。
这可以是关于某一特定经验的本质或某一主题的描述和解释。
2. 设计研究方法:现象学研究通常采用质性研究方法,如深度访谈、观察和分析。
研究者应根据研究问题和目的选择适当的方法。
3. 收集数据:根据研究方法的选择,研究者进行数据的收集。
这可能包括面对面的访谈,观察参与者的行为,收集书面材料等。
4. 描述和分析数据:在这一步骤中,研究者将对收集到的数据进行整理、分类和分类,并提取有关主题和意义的信息。
这可能涉及编码、归纳和分析数据。
5. 解释结果:通过反思和解释数据,研究者将试图理解个体的意义构建和经验。
这将包括对数据中的模式、主题和关联的识别和解释。
6. 发表研究结果:最后,研究者将准备研究报告或论文,将结果与已有的理论和研究进行对比,并与学术界和相关领域分享研究的发现。
现象学研究的优势和局限性:现象学研究的优势在于其关注个体的主观体验和意义,可以提供深入的理解和洞察力。
它能够揭示现实世界的多样性和复杂性,以及个体对此的理解和经验。
此外,现象学研究方法强调经验的真实性和亲身体验,可以避免理论性假设的干扰,直接从经验本身获得信息。
然而,现象学研究也存在局限性。
由于其侧重于个体的主观体验,结果的可泛化性有限。
此外,现象学研究通常使用小样本,难以代表整个人群或社会。
这可能导致在相同问题上出现不同的结果。
总结:现象学研究是一种描述和解释人类经验和现实世界的哲学研究方法。
安宁疗护高级实践护士核心能力指标体系的构建
Human Resource安宁疗护高级实践护士核心能力指标体系的构建赵艺媛陆宇皓王云国仁秀杨红杨飕[摘要]目的:构建安宁疗护专业高级实践护士的核心能力指标体系。
方法:通过文献回顾,根据专家协调小组意见,自行设计专家咨询问卷,对全国7个省份15所医院从事临终护理实践、护理管理、姑息医疗以及从事院校安宁疗护教育4个领域的23名资深专家进行两轮德尔菲专家咨询。
结果:构建的安宁疗护高级实践护士的核心能力指标体系包括沟通及合作能力、临床实践能力、专业发展能力、文化和灵性照护能力、伦理与法律相关能力、教育教学能力、系统资源管理能力、循证护理及科研能力共8个方面31个二级指标。
结论:明确了安宁疗护高级实践护士应具备的核心能力,为培养安宁疗护领域高级实践护士提供依据。
[关键词]安宁疗护;高级实践护士;核心能力;德尔菲法[中图分类号]R47[DOI]10.3969/j.issn.l672-1756.2021.02.022The research in core competencies of Hospice Advanced Practice Nurse/ZHAO Yiyuan,LU Yuhan,WANG Yun,GUO Renxiu,YANG Hong,YANG Yang//Department of Head and Neck Surgery,Beijing Cancer Hospital and Beijing Institute for Cancer Research,100142,China III Chinese Nursing Management-2021,21⑵:268-273[Abstract]Objective:To construct the core competencies of Hospice Advanced Practice Nurse(APN).Methods:Two rounds of Delphi consultation questionnaires were sent to23experts who were from15departments in7provinces and cities.They were experienced in areas of clinical hospice nursing,nursing administration,hospice medicine and nursing education.Results:The core competencies of Hospice Advanced Practice Nurse were communication and collaboration, clinical practice,professional development,ethical and cultural care,system resource management,evidence-based nursing and nursing research.Conclusion:This research ascertains the core competencies that Hospice APN should have,and applies basis to train APN in hospice specialty.[Keywords]hospice care;Advanced Practice Nurse;core competencies;Delphi method基金项目:北京大学护理学院教育教学研究课题重点立项项目(2017NER04Z)作者单位:北京大学肿瘤医院暨北京市肿瘤防治研究所头颈外科,100142(赵艺媛);护理部(陆宇皓,杨红);中西医暨老年医学科(王云);消化内科(国仁秀);乳腺癌预防和治疗中心(杨她)作者简介:赵艺媛,硕士,副主任护师,护士长通信作者:陆宇賭,硕士,主任护师,护理部主任,E-mailJu**************118]吴奇云,程念开,沈霞娟.重症监护室护士视角下临终患者需求的质性研究.现代临床护理,2017,16(2):47-51.[19]Velarde-Garcia JF,Luengo-gonzalez R.Gonzalez-hervias R,et al.Facing death inthe intensive care unit.A phenomenologicalstudy of nurses'experiences.ContempNurse,2016,52(1):1-12.[20]Yu HU,Chan S.Nurses response todeath and dying in an intensive care unit:a qualitative study.Journal of ClinicalNursing,2010,19(7/8):1167-1169.[21]Mu PF,Tseng YM,Wang CC,et al.Nurses'experiences in cnd-of-life care in the PICU:a qualitative systematic review.NursingScience Quarterly,2019,32(1):12-22.[22]Azoulay E,Pochard F,Kentish-BarnesN,et al.Risk of Post-Traumatic StressSymptoms in family members of IntensiveCare Unit patients.Am J Respir Crit CareMed,2005,171(9):987-994.[2引熊莺,许跚文,张力,等.重症监护室临终关怀病房的设置:11例临终患者的护理体会冲国临床护理,2018,10(6):505507.[24]Wang T,Molassiotis A,Chung BPM,et al.Current research status of palliative care inMainland China.Journal of Palliative Care,2018,33(4):215-241.[25|刘霖,徐燕,袁长蓉.影响肿瘤姑息护理培训内容制定的因素分析•护理学报,2008,15(5):1-3.[26]Mengjie L,Houxiu Z,Changbi L,et al.End-of-life decision-making experiencesand influencing factors reported byIntensive Care Unit medical and nursingstaff members in southwestern China:aqualitative study.Journal of Hospice&Palliative Nursing,2015,17(6):544-550.[27]Siffleet J,Williams AM,Rapley P,et al.Delivering best care and maintainingemotional wellbeing in the intensive careunit:the perspective of experienced nurses.Applied Nursing Research,2015,28(4):305-引0.[28]程人佳,徐国帅,张庆红,等.重症监护室死亡患者默哀仪式的实施及医护人员体验的研究.护理学杂志,2018,33(22):57-60.[29]杨凤姣,陈欢,王海燕,等.我国临终关怀面临的突出问题及解决措施•中国医学伦理学,2019,32(12):1562—1565.[30]崔媛媛.构建我国预先医疗指示制度研究.北京:北京中医药大学,2017.[收稿日期:2020-02-09][修回日期:2020-06-30](编辑:孙蕊英文编辑:程丽)268Chinese Nursing Management Vol.21,No.2,February15,2021Human Resource安宁疗护是指由医务人员为终末期患者提供的全方位的照护,包括生理、心理、精神和社会支持,目标是帮助终末期患者舒适、平静、有尊严地离世"7,其服务对象包括了患者及其家庭。
科学精神作文
科学精神作文英文回答:The scientific method is a systematic and logical approach to the study of natural phenomena. It involves making observations, forming hypotheses, testing hypotheses, and drawing conclusions. The scientific method is essential to the progress of science, as it allows scientists tobuild upon the work of others and to make new discoveries.One of the most important aspects of the scientific method is the ability to make objective observations. This means that scientists must be able to observe the world without bias or preconceptions. They must also be able to record their observations accurately and objectively.Once scientists have made observations, they can beginto form hypotheses. A hypothesis is a tentative explanation for a phenomenon. Hypotheses must be testable, meaning that they can be supported or refuted through experimentation.The next step in the scientific method is to test the hypothesis. This involves designing and conducting an experiment. The experiment should be designed to test the hypothesis in a controlled manner. The results of the experiment can then be used to support or refute the hypothesis.If the results of the experiment support the hypothesis, then the scientist can draw a conclusion. The conclusion should be a statement of the relationship between the variables that were studied in the experiment.The scientific method is a powerful tool for understanding the natural world. It is a process that is based on observation, experimentation, and logical reasoning. The scientific method has led to many important discoveries, and it continues to be an essential tool for the progress of science.中文回答:科学方法是研究自然现象的一种系统合理的方法。
人本治疗法
人本治疗法人本治疗法1 导言人本治疗法(Person-dentered Therapy)又名当事人中心治疗法(Client-centered Therapy)的创始人为美国心理学家卡尔·罗杰士( Carl Rogers 1902—1987)。
罗杰士自1940年开始建立此疗法的基本概念和治疗方式。
此疗法充分反映出罗杰士的个人体验和理想。
罗杰士生于一个父母管教非常严格的清教基督徒家庭。
父母高度强调刻苦、忍耐、自我约束和崇高的道德标准,引致早期的罗杰士内心常有强烈的压迫感、自信心低落、孤寂、与其他人的关系疏离,不敢与人坦诚透露内心的意愿,因为怕被家人批评为贪婪。
故此,罗杰士创造此治疗法是刻意希望帮助协助人释放内心的枷锁,开阔自己的自由感,重拾本身活泼的动力,忠于自己和尊重自己。
此疗法亦深受罗杰士的兴趣所影响,罗杰士曾攻读农务科,非常喜爱大自然和栽培植物。
他认为人的成长好比植物的成长——最重要的是周围有适当栽培的条件;故此,他所订立的一些基本条件(core conditions)亦成为此治疗法的精髓。
基于此治疗法很着重对生命的投入和体验,以及对人的尊崇,它被视为“存在—人道主义派”的主流,与强调人是潜意识被控制的心理分析派、强调人是被环境控制的行为治疗派分庭抗礼,从而成为辅导界的第三势力。
人本治疗法的历史发展在五十多年的发展历史中,人本治疗法经历过不少的改变。
罗杰氏和他的跟随者一直作出这方面的研究和临床实验,不断修正治疗的理论和方式,务求使它更适合时代的需求。
大致上来说,人本治疗法的发展可分为以下四个阶段(Corey,1986a)一第一阶段(一九四零至一九五零年)罗杰氏于一九四二年所作的书《辅导与心理治疗》(Counselingand Psycherapy)奠定了这治疗法的基本概念。
当时它常被称为非指引式辅导(non-directive therapy),因为罗杰氏强调辅导员要避免表露个人的看法和意愿,要尽量减低自己对当事人的影响,免致妨碍当事人的自然成长;所以,当时的治疗法提倡辅导员接受当事人,与他建立一个融洽、宽容和不带批评性(non-judgmental)的气氛,以及信赖当事人能以他的内在资源来协助自己。
Field quantization in inhomogeneous anisotropic dielectrics with spatio-temporal dispersion
a r X i v :q u a n t -p h /0702010v 2 16 F eb 2007Field quantization in inhomogeneous anisotropic dielectrics with spatio-temporal dispersionL G Suttorp Instituut voor Theoretische Fysica,Universiteit van Amsterdam,Valckenierstraat 65,1018XE Amsterdam,The Netherlands Abstract.A quantum damped-polariton model is constructed for an inhomogeneous anisotropic linear dielectric with arbitrary dispersion in space and time.The model Hamiltonian is completely diagonalized by determining the creation and annihilation operators for the fundamental polariton modes as specific linear combinations of the basic dynamical variables.Explicit expressions are derived for the time-dependent operators describing the electromagnetic field,the dielectric polarization and the noise term in the latter.It is shown how to identify bath variables that generate the dissipative dynamics of the medium.PACS numbers:42.50.Nn,71.36.+c,03.70.+k Submitted to:J.Phys.A:Math.Gen.1.IntroductionQuantization of the electromagneticfield in a linear dielectric medium is a nontrivial task for various reasons.First of all,since the response of a dielectric to externalfields is frequency-dependent in general,temporal dispersion should be taken into account.The well-known Kramers-Kronig relation implies that dispersion is necessarily accompanied by dissipation,so that the quantization procedure has to describe an electromagneticfield that is subject to damping.Furthermore,since the transverse and the longitudinal parts of the electromagneticfield play a different role in the dynamics,the quantization scheme should treat these parts separately. For inhomogeneous and spatially dispersive media this leads to complications in the quantization procedure,which further increase in the presence of anisotropy.When the losses in a specific range of frequencies are small,temporal dispersion can be neglected.Field quantization in an inhomogeneous isotropic dielectric medium without spatio-temporal dispersion has been accomplished by employing a generalized transverse gauge,which depends on the dielectric constant[1]–[6].A phenomenological scheme forfield quantization in lossy dielectrics has been formulated on the basis of thefluctuation-dissipation theorem[7]–[10].By adding a fluctuating noise term to the Maxwell equations and postulating specific commutation relations for the operator associated with the noise,one arrives at a quantization procedure that has been quite successful in describing the electromagneticfield in lossy dielectrics.An equivalent description in terms of auxiliaryfields has been given as well[11,12],while a related formalism has been presented recently[13].However, all of these quantization schemes have the drawback that the precise physical nature of the noise term is not obvious,since its connection to the basic dynamical variables of the system is left unspecified.As a consequence,the status of the commutation relations for the noise operator is that of a postulate.A justification of the above phenomenological quantization scheme has been sought by adopting a suitable model for lossy dielectrics.To that end use has been made of an extended version of the Hopfield polariton model[14]in which damping effects are accounted for by adding a dynamical coupling to a bath environment. Huttner and Barnett[15,16]were thefirst to employ such a damped-polariton model in order to achievefield quantization for a lossy dielectric.Their treatment,which is confined to a spatially homogeneous medium,yields an explicit expression for the noise term as a linear combination of the canonical variables of the model.In a later development,an alternative formulation of the quantization procedure in terms of path integrals has been given[17],while Laplace transformations have been used to simplify the original formalism[18].More recently,the effects of spatial inhomogeneities in the medium have been incorporated by solving an inhomogeneous version of the damped-polariton model[19]–[21].In this way a full understanding of the phenomenological quantization scheme has been reached,at least for those dielectrics that can be represented by the damped-polariton models mentioned above.The latter proviso implies a limitation in various ways.First,one would like to include in a general model not only the effects of spatial inhomogeneity,but also those of spatial dispersion.Furthermore,it would be desirable to incorporate the consequences of spatial anisotropy,so that the theory encompasses crystalline media as well.Finally,while treating temporal dispersion and the associated damping,we would like to refrain from introducing a bath environment in the Hamiltonian from the start.Instead,we wish to formulate the Hamiltonian interms of a full set of material variables,from which the dielectric polarization emerges by a suitable projection.In this way we will be able to account for any temporal dispersion that is compatible with a few fundamental principles like causality and net dielectric loss.For a homogeneous isotropic dielectric without spatial dispersion such an approach has been suggested before[16,22].Recently,several attempts have been made to remove some of the limitations that are inherent to the earlier treatments.In[23]the effects of spatial dispersion are considered in a path-integral formalism for a model that is a generalization of that of the original Huttner-Barnett approach.The discussion is confined to homogeneous dielectrics and to leading orders in the wavenumber,so that an analysis of the effects of arbitrary spatial dispersion in an inhomogeneous medium is out of reach.In [24]crystalline media have been discussed in the framework of a damped-polariton model with an anisotropic tensorial bath coupling.A complete diagonalization of the model along the lines of[15,16]turned out to face difficulties due to the tensorial complexity,so that the full dynamics of the model is not presented.Both spatial dispersion and anisotropy are incorporated in the quantization scheme discussed in [25].Use is made of a Langevin approach in which a damping term of a specific form is introduced.The commutation relations for the noise operator are postulated,as in the phenomenological quantization scheme.Finally,several treatments have appeared in which a dielectric model is formulated while avoiding the explicit introduction of a bath[26,27].However,a complete expression for the noise polarization operator in terms of the basic dynamical variables of the model is not presented in these papers.A direct proof of the algebraic properties of the latter operator is not furnished either.In the present paper,we shall show how the damped-polariton model can be generalized in such a way that all of the above restrictions are removed.As we shall see,our general model describes the quantization and the time evolution of the electromagneticfield in an inhomogeneous anisotropic lossy dielectric with arbitrary spatio-temporal dispersion.A crucial step in arriving at our goals will be the complete diagonalization of the Hamiltonian.It will lead to explicit expressions for the operators describing the electromagneticfield and the dielectric polarization,and for the noise contribution contained in the latter.In this way the commutation relations for the noise operator will be derived rigorously from our general model,instead of being postulated along the lines of the phenomenological scheme.Finally,we shall make contact with previous treatments by showing how to construct a bath that generates damping phenomena in the dynamical evolution of the model.2.Model HamiltonianIn this section we shall construct the general form of the Hamiltonian for a polariton model describing an anisotropic inhomogeneous dispersive dielectric.The result, which we shall obtain by starting from a few general principles,will contain several coefficients that can be chosen at will.As we shall see in a subsequent section,these coefficients can be adjusted in such a way that the susceptibility gets the appropriate form for any causal lossy dielectric that we would like to describe.The Hamiltonian of the electromagneticfield is taken to have the standard form:H f= d r 12µ0[∇∧A(r)]2 (1) with the Hermitian vector potential A(r)and its associated Hermitian canonicalmomentumΠ(r).We use the Coulomb gauge∇·A=0.In this gauge bothΠand A are transverse.The canonical commutation relations read[Π(r),A(r′)]=−i¯hδT(r−r′),[Π(r),Π(r′)]=0,[A(r),A(r′)]=0(2) where the transverse delta function is defined asδT(r)=Iδ(r)+∇∇(4πr)−1,with I the unit tensor.The Hamiltonian of the dielectric material medium is supposed to have the general formH m=¯h d r ∞0dωωC†m(r,ω)·C m(r,ω)(3) with the standard commutation relations for the creation and annihilation operators: [C m(r,ω),C†m(r′,ω′)]=Iδ(r−r′)δ(ω−ω′),[C m(r,ω),C m(r′,ω′)]=0.(4) The medium operators commute with thefield operators.The material creation and annihilation operators are assumed to form a complete set describing all material degrees of freedom.Hence,any material dynamical variable, for instance the dielectric polarization density,can be expressed in terms of these operators.For a linear dielectric medium,the Hermitian polarization density is a linear combination of the medium operators,which has the general form:P(r)=−i¯h d r′ ∞0dω′C m(r′,ω′)·T(r′,r,ω′)+h.c.(5) The complex tensorial coefficient T appearing in this expression will be determined later on,when the dielectric susceptibility is properly identified.On a par with P we define its associated canonical momentum density W,again as a linear combination of the medium operatorsW(r)=− d r′ ∞0dω′ω′C m(r′,ω′)·S(r′,r,ω′)+h.c.(6) with a new complex tensorial coefficient S that is closely related to T,as we shall see below.For future convenience we inserted a factorω′in the integrand and a minus sign in front of the integral.As W and P are a canonical pair,they must satisfy the standard commutation relations[W(r),P(r′)]=−i¯h Iδ(r−r′),[W(r),W(r′)]=0,[P(r),P(r′)]=0.(7)Hence,the coefficients S and T have to fulfill the requirements:d r′′ ∞0dω′′˜T(r′′,r,ω′′)·T∗(r′′,r′,ω′′)−c.c.=0(8)d r′′ ∞0dω′′ω′′˜S(r′′,r,ω′′)·T∗(r′′,r′,ω′′)+c.c.=Iδ(r−r′)(9)d r′′ ∞0dω′′ω′′2˜S(r′′,r,ω′′)·S∗(r′′,r′,ω′′)−c.c.=0(10)where the tilde denotes the transpose of a tensor and the asterisk the complex conjugate.Furthermore,the Hamiltonian should contain terms describing the interaction between thefield and the medium.Two contributions can be distinguished:a transverse part and a longitudinal part.In a minimal-coupling scheme,which we shall adopt here,the transverse part is a bilinear expression involving the transversevector potential A and the canonical momentum density W.To ensure compatibility with Maxwell’s equations an expression quadratic in A should be present as well,as we shall see in the following.For dielectrics with spatial dispersion both expressions are non-local.The general form of the transverse contribution to the interaction Hamiltonian isH i=−¯h d r d r′W(r)·F1(r,r′)·A(r′)+1d r d r′∇·P(r)∇′·P(r′)2ε0 d r{[P(r)]L}2=Π(r,t)(13)ε0˙Π(r,t)=1ε0 d r′T∗(r,r′,ω)·[P(r′,t)]L′(15) where all operators now depend on time.The subscript L′denotes the longitudinal part with respect to r′.The time derivative of the polarization density follows by combining(5)and(15):˙P(r,t)=−¯h d r′ ∞0dω′ω′C m(r′,ω′,t)·T(r′,r,ω′)−¯h d r′ d r′′ d r′′′ ∞0dω′ω′˜T(r′,r,ω′)·S∗(r′,r′′,ω′)·F1(r′′,r′′′)·A(r′′′,t)¯h−iEliminatingΠfrom(13)and(14)wefind an inhomogeneous wave equation for the vector potential∆A(r,t)−12ε0[Π(r)]2+12¯h d r d r′A(r)·F(r,r′)·A(r′)+1The complex tensorial coefficient T can be chosen freely.It has to satisfy two constraints,thefirst of which has been written already in(8).The second one follows by substituting(20)in(10):d r′′ ∞0dω′′ω′′2˜T(r′′,r,ω′′)·T∗(r′′,r′,ω′′)−c.c.=0.(22)Finally,insertion of(20)in(9)leads to the equalityd r′′ ∞0dω′′ω′′˜T(r′′,r,ω′′)·T∗(r′′,r′,ω′′)+c.c.=F(r,r′).(23)This relation defines the real tensor F in terms of T.It shows that F(r,r′)satisfies the symmetry property˜F(r,r′)=F(r′,r),as we know already from the way F2occurs in (11).As an integral kernel the tensor F(r,r′)is positive-definite.This is established by taking the scalar products of(23)with real vectors v(r)and v(r′),and integrating over r and r′.The result is positive for any choice of v.As a consequence,the inverse of F is well defined.The polarization density is given by(5),while the canonical momentum density reads according to(6)with(20):W(r)=− d r′ d r′′ ∞0dω′ω′C m(r′,ω′)·T(r′,r′′,ω′)·F−1(r′′,r)+h.c.(24) where the right-hand side contains the inverse of F.The Hamiltonian(21)has been constructed by starting from general forms for its parts H f,H m,H i and H es and requiring consistency with Maxwell’s equations.It may be related to a Lagrange formalism,as is shown in Appendix A.In the following we shall investigate the dynamics of the model defined by(21). As the Hamiltonian is quadratic in the dynamical variables it is possible to accomplish a complete diagonalization.This will be the subject of the next section.3.Diagonalization of the HamiltonianWe wish tofind a diagonal representation of the Hamiltonian(21)in the formH=¯h d r ∞0dωωC†(r,ω)·C(r,ω).(25) The creation and annihilation operators satisfy the standard commutation relations of the form(4).They are linear combinations of the dynamical variables in(21): C(r,ω)= d r′ f1(r,r′,ω)·A(r′)+f2(r,r′,ω)·Π(r′)+ ∞0dω′ f3(r,r′,ω,ω′)·C m(r′,ω′)+f4(r,r′,ω,ω′)·C†m(r′,ω′) (26) with as-yet unknown tensorial coefficients f i,thefirst two of which are taken to be transverse in their second argument.To determine f i we use Fano’s method[28]:we evaluate the commutator[C(r,ω),H]and equate the result to¯hωC(r,ω).Comparing the contributions involving the various canonical operators we arrive at the four equationsii ε0 d r ′′ d r ′′′ ∞0dω′′{f 3(r ,r ′′,ω,ω′′)·[T ∗(r ′′,r ′′′,ω′′)]L ′′′+f 4(r ,r ′′,ω,ω′′)·[T (r ′′,r ′′′,ω′′)]L ′′′}·˜T (r ′,r ′′′,ω′)=ωf 3(r ,r ′,ω,ω′)(29)−i ¯h ω′ d r ′′f 2(r ,r ′′,ω)·˜T∗(r ′,r ′′,ω′)−ω′f 4(r ,r ′,ω,ω′)−¯h c 2d r ′′T ∗(r ,r ′′,ω)·[G (r ′′,r ′,ω−i 0)]T ′(31)f 2(r ,r ′,ω)=i µ0ω d r ′′T ∗(r ,r ′′,ω)·[G (r ′′,r ′,ω−i 0)]T ′(32)f 3(r ,r ′,ω,ω′)=I δ(r −r ′)δ(ω−ω′)−µ0¯h ω d r ′′ d r ′′′T ∗(r ,r ′′,ω)·[G (r ′′,r ′′′,ω−i 0)]T ′′′·˜T(r ′,r ′′′,ω′)+µ0¯h ω2ω+ω′d r ′′ d r ′′′T ∗(r ,r ′′,ω)·G (r ′′,r ′′′,ω−i 0)·˜T ∗(r ′,r ′′′,ω′).(34)The Green function G (r ,r ′,z )occurring in these expressions is defined as the solution of the differential equation:− G (r ,r ′,z )×←−∇′ ×←−∇′+z 2c2 d r ′′G (r ,r ′′,z )·χ(r ′′,r ′,z )=I δ(r −r ′)(35)The spatial derivative operator ∇′acts to the left on the argument r ′of G (r ,r ′,z ).According to this inhomogeneous wave equation the Green function determines the propagation of waves through a medium that is characterized by a tensor χ(r ,r ′,z).The latter plays the role of a non-local anisotropic susceptibility,as will become clear in the next section.It is defined in terms of T and its complex conjugate asχ(r,r′,z)≡¯hω−z˜T(r′′,r,ω)·T∗(r′′,r′,ω)+1ε0 d r′′˜T(r′′,r,ω)·T∗(r′′,r′,ω)(39) for positiveωand byχ(r,r′,ω+i0)−χ(r,r′,ω−i0)=−2πi¯h2πi ∞−∞dω1ε0F(r,r′)(43)∞−∞dωω2[χ(r,r′,ω+i0)−χ(r,r′,ω−i0)]=0.(44)Incidentally,we remark that for large|z|the asymptotic behaviour ofχfollows from (41)with(42)–(44)asχ(r,r′,z)≃−¯hz2+O 1c2G(r,r′,z)+ z2The medium operator C m (r ,ω)is a linear combination of the diagonalizing operator and its Hermitian conjugate:C m (r ,ω)= d r ′ ∞0dω′ ˜f ∗3(r ′,r ,ω′,ω)·C (r ′,ω′)−˜f 4(r ′,r ,ω′,ω)·C †(r ′,ω′) (53)asfollowsbytaking the inverse of (26).Substituting (33)–(34)and inserting the result in (5)we get after some algebraP (r ,t )=i ¯h c 2 d r′ d r ′′ ∞0dωω2[G (r ,r ′,ω+i 0)]L ·˜T(r ′′,r ′,ω)·C (r ′′,ω)e −i ωt +h .c .(55)From the Maxwell equation ∇·(ε0E +P )=0it follows that the left-hand side is proportional to the longitudinal part [E (r ,t )]L of the electric field.The ensuing expression for the latter is analogous to (52),so that we arrive at the following result for the complete electric field:E (r ,t )=i µ0¯h d r ′ d r ′′ ∞0dωω2G (r ,r ′,ω+i 0)·˜T(r ′′,r ′,ω)·C (r ′′,ω)e −i ωt +h .c .(56)Inspection of (54)shows that the polarization consists of two terms.The first term is proportional to the electric field,at least in Fourier space and after taking a spatial convolution integral.The proportionality factor is χ(r ,r ′,ω),which plays the role of a susceptibility tensor,as we anticipated in the previous section.The second term in (54)is not related to the electric field.It represents a noise polarization density P n (r ,t )defined as P n (r ,t )=−i ¯h d r ′ ∞0dω˜T (r ′,r ,ω)·C (r ′,ω)e −i ωt +h .c .(57)that has to be present so as to yield a quantization scheme in which the validity of the canonical commutation relations in the presence of dissipation is guaranteed.Introducing the Fourier transform P n (r ,ω)via P n (r ,t )= ∞dωP n (r ,ω)e −i ωt +h .c .(58)and its counterparts E (r ,ω)and P (r ,ω),we get from (54)with (56):P (r ,ω)= d r ′χ(r ,r ′,ω+i 0)·E (r ′,ω)+P n (r ,ω).(59)The Fourier-transformed noise polarization density is proportional to the diagonalizing operator:P n (r ,ω)=−i ¯h d r ′˜T(r ′,r ,ω)·C (r ′,ω).(60)as follows from (57)and(58).As wehavegot now an explicit expression for P n (r ,ω)we can derive its commutation relation.By employing (39)we obtain:P n (r ,ω),P †n(r ′,ω′) =−i ¯h ε0c 2 d r′ d r ′′ ∞0dωω2χ(r ,r ′,ω+i 0)·G (r ′,r ′′,ω+i 0)·P n (r ′′,ω)e −i ωt+ ∞0dωP n (r ,ω)e −i ωt +h .c .(64)By adding (62)and (64)we get an expression for the dielectric displacement D (r ,t ).Upon using (47)we may write it as D (r ,t )=− d r ′ ∞0dω∇×[∇×G (r ,r ′,ω+i 0)]·P n (r ′,ω)e −i ωt +h .c .(65)Clearly,the dielectric displacement is purely paring with (63)we find that Maxwell’s equation ∇×B (r ,t )=µ0∂D (r ,t )/∂t is satisfied.It is instructive to return to the time-dependent representation of the linear constitutive relation (59):P (r ,t )= d r ′ t−∞dt ′χ(r ,r ′,t −t ′)·E (r ′,t ′)+P n (r ,t )(66)with the time-dependent susceptibility tensor defined by writing:χ(r ,r ′,ω+i 0)= ∞0dt χ(r ,r ′,t )e i ωt .(67)The convolution integral in the first term of (66),which expresses the causal response of the medium,depends on the electric field at all times t ′preceding t and at all positions r ′,whereas the second contribution is the noise term,which in classical theory does not appear.Sometimes [26]a different splitting of the various contributions to the polarization density is proposed,by writing an equation of the general form of (66)in which the response term covers only a limited range of values of t ′,for instance t ′∈[0,t ]for t >0.In such a formulation the convolution integral does not represent the full causal response of the medium,so that part of the response is hidden in the second term.As a consequence,the latter is no longer a pure noise term,so that it cannot be omitted in the classical version of the theory.The above expressions for the fields and the polarization density in terms of the Fourier-transformed noise polarization density satisfying the commutation relations (61)are the central results in the present formalism for field quantization in inhomogeneous anisotropic dielectric media with spatio-temporal dispersion.Although we are describing dissipative media,it has not been necessary to explicitlyintroduce a bath,as is commonly done in the context of damped-polariton treatments [15,16,19,20].In the next section,we shall show how a bath may be identified in the present model.5.Bath degrees of freedomIn the Hamiltonian(21)the dielectric medium is described by the operators C m(r,ω) and C†m(r,ω).The polarization density P(r)and its canonical conjugate W(r)are given in(5)and(24)as suitable linear combinations of the medium operators C m and C†m.Since the latter depend on the continuous variableω,they describe many more degrees of freedom than P and W.The extra degrees of freedom can be taken together to define a so-called‘bath’,which is independent of P and W.Although the name might suggest otherwise,the bath as introduced in this way is part of the medium itself,and not some external environment.Its role is to account for the dissipative effects in the dispersive medium,which may arise for instance through a leak of energy by heat production.In the following we shall identify the operators associated to the bath.Subsequently,we shall show how the Hamiltonian can be rewritten so as to give an explicit description of the coupling between the polarization and the bath.In this way,we will be able to compare our model to its counterparts in previous papers [15,16,19,20].The bath will be described by operators C b(r,ω)and C†b (r,ω)satisfying the usualcommutation relations.These bath operators are linear combinations of the medium operators:C b(r,ω)= d r′ ∞0dω′ H1(r,r′,ω,ω′)·C m(r′,ω′)+H2(r,r′,ω,ω′)·C†m(r′,ω′) (68) with tensor coefficients H i that will be determined presently.Since the bath variables are by definition independent of both P(r′)and W(r′)for all r′,they have to commute with the latter.With the use of(5)and(24)we get from these commutation relations the following conditions:d r′′ ∞0dω′′[H1(r,r′′,ω,ω′′)·T∗(r′′,r′,ω′′)+H2(r,r′′,ω,ω′′)·T(r′′,r′,ω′′)]=0(69)d r′′ ∞0ω′′ω′′[H1(r,r′′,ω,ω′′)·T∗(r′′,r′,ω′′)−H2(r,r′′,ω,ω′′)·T(r′′,r′,ω′′)]=0.(70)To determine H i we start from the following Ansatz:H1(r,r′,ω,ω′)= d r′′ δ(ω−ω′)h1(r,r′′,ω)+1ω+ω′h2(r,r′′,ω)·˜T∗(r′,r′′,ω′)(72) with new tensor coefficients h i.Substituting these expressions in(69)–(70)and using (36)and(39),wefind that both of these conditions are simultaneously satisfied whenh 1and h 2are related as d r ′′h 2(r ,r ′′,ω)·χ(r ′′,r ′,ω+i 0)==12i d r ′′ d r ′′′h 1(r ,r ′′,ω)·[χ(r ′′,r ′′′,ω+i 0)−χ(r ′′,r ′′′,ω−i 0)]·˜h ∗1(r ′,r ′′′,ω)==π¯h ε0d r ′′T ∗(r ,r ′′,ω)·χ−1(r ′′,r ′,ω+i 0).(76)It should be noted that the coefficients h i are determined up to a unitary transformation.This freedom,which is available to H i as well,corresponds to a natural arbitrariness in the choice of the bath operators themselves.As the bath operators have been identified now,we can rewrite the Hamiltonian so as to clarify their role in the dynamics of our model.To that end we have to eliminate the medium operators C m in favor of the bath operators C b .Employing(5),(24)and (68)we can write the medium operators as:C m (r ,ω)= d r ′T ∗(r ,r ′,ω)· i 2ε0[Π(r )]2+12πi ¯h 2 d r d r ′ d r ′′ d r ′′′P (r )·F −1(r ,r ′)· ∞0dωω3[χ(r ′,r ′′,ω+i 0)−χ(r ′,r ′′,ω−i 0)] ·F −1(r ′′,r ′′′)·P (r ′′′)+12¯hd r d r ′W (r )·F (r ,r ′)·W (r ′)−¯h d r d r ′W (r )·F (r ,r ′)·A (r ′)+1i¯h −causality and positive-definiteness of the dissipative energy loss.Incidentally,it may be remarked that amplifying dielectric media,which have been treated in the context of the phenomenological quantization scheme as well[10,29],are not covered by the present damped-polariton model.To describe media with a sustained gain,e.g.a laser above threshold,one has to incorporate a driving mechanism in the Hamiltonian, which accounts for the ongoing input of energy that is indispensable for a stationary gain.As we have shown,the time evolution of the dynamical variables forfield and matter can be determined completely by deriving the operators that diagonalize the Hamiltonian.The diagonalizing operators are closely related to the noise part of the polarization density,which plays an important role in the phenomenological quantization scheme.The proof of the commutation properties of the noise polarization density follows from its relation to the diagonalizing operators.In setting up our model Hamiltonian we have avoided to introduce a bath environment from the beginning.The subsequent formalism could be developed without ever discussing such a bath.Nevertheless,one may be interested in an analysis of the complete set of degrees of freedom of the dielectric medium in our model.If that analysis is carried out,onefinds,as we have seen above,that specific combinations of medium variables can be associated to what may be called a bath.The coupling of the polarization to this bath can be held responsible for the dissipative losses that characterize a dispersive dielectric.AcknowledgmentsI would like to thank dr.A.J.van Wonderen for numerous discussions and critical comments.Appendix grangian formulationIn this appendix we shall show how the Hamiltonian(21)can be related to a Lagrange formalism.We start by postulating the following Lagrangian for an anisotropic linear dielectric with spatio-temporal dispersion that interacts with the electromagneticfield: L= d r 12µ0[∇∧A(r)]2+12ε0 d r{[P(r)]L}2.(A.1) Here A(r)is the transverse vector potential and Q m(r,ω)are material coordinates depending on position and frequency.The polarization density P(r)is taken to be an anisotropic and non-local linear combination of these material coordinates of the form P(r)= d r′ ∞0dω′Q m(r′,ω′)·T0(r′,r,ω′)(A.2) with a real tensor coefficient T0(r,r′,ω).One easily verifies that the Lagrangian equations have the form1∆A(r,t)−¨Q m (r ,ω,t )+ω2Q m (r ,ω,t )= d r T 0(r ,r ′,ω)·E (r ′,t )(A.4)with the electric field given as E (r ,t )=−˙A (r ,t )−(1/ε0)[P (r ,t )]L .The first Lagrangian differential equation is consistent with Maxwell’s equation,as it should.The second Lagrangian equation shows that the material coordinates are harmonic variables that are driven by the electric field in an anisotropic and non-local way.Introducing the momenta Π(r )and P m (r ,ω)associated to A and Q m asΠ(r )=ε0˙A (r )(A.5)P m (r ,ω)=˙Q m (r ,ω)+ d r ′T 0(r ,r ′,ω)·A (r ′)(A.6)we obtain the Hamiltonian corresponding to (A.1)in the standard fashion.The result is:H = d r 12µ0[∇∧A (r )]2+12 d r d r ′ d r ′′ ∞dωA (r )·˜T 0(r ′,r ,ω)·T 0(r ′,r ′′,ω)·A (r ′′)+12 1/2d r ′ C m (r ′,ω)·U (r ′,r ,ω)+C †m (r ′,ω)·U ∗(r ′,r ,ω) (A.8)Q m (r ,ω)=i ¯hAppendix B.Evaluation of the tensorial coefficients f i In thisappendix wewill showhowtheequations (27-30)can be solved.We start by using (27)to eliminate f 1from (28).As a result we obtain the differential equation:∆′f 2(r ,r ′,ω)+ω2ε0 d r′′ d r ′′′ d r ′′′′ ∞0dω′′{f 3(r ,r ′′,ω,ω′′)·[T ∗(r ′′,r ′′′,ω′′)]L ′′′+f 4(r ,r ′′,ω,ω′′)·[T (r ′′,r ′′′,ω′′)]L ′′′}·˜T(r ′′′′,r ′′′,ω′)·T ∗(r ′′′′,r ′,ω′)=0.(B.2)A similar relation is obtained by multiplying (30)by T (r ′,r ′′′′,ω′)and integrating over r ′:−i ¯h ω′ d r ′′ d r ′′′f 2(r ,r ′′,ω)·˜T∗(r ′′′,r ,′′,ω′)·T (r ′′′,r ′,ω′)−(ω+ω′) d r ′′f 4(r ,r ′′,ω,ω′)·T (r ′′,r ′,ω′)−¯h c 2f 2(r ,r ′,ω)−i µ0ωd r ′′ ∞0dω′′{f 3(r ,r ′′,ω,ω′′)·[T ∗(r ′′,r ′,ω′′)]T ′+f 4(r ,r ′′,ω,ω′′)·[T (r ′′,r ′,ω′′)]T ′}=0.(B.5)Here we used the transversality of f 2(r ,r ′,ω)in its second argument to write the first term as a repeated vector product,with the spatial derivative operator ∇′acting to the left on theargument r ′of thefunction f 2(r ,r ′,ω).The integral in (B.5)contains the transverse parts of T and T ∗only.A more natural form of the differential equation,with the full tensors T and T ∗,is obtained by introducing instead of f 2a new tensor g defined as:g (r ,r ′,ω)≡i ωf 2(r ,r ′,ω)−1c 2g (r ,r ′,ω)+µ0ω2d r ′′ ∞0dω′′[f 3(r ,r ′′,ω,ω′′)·T ∗(r ′′,r ′,ω′′)+f 4(r ,r ′′,ω,ω′′)·T (r ′′,r ′,ω′′)]=0.(B.7)The integral contribution still depends on f 3and f 4,so that the differential equation is not yet in closed form.However,we may rewrite the integral in such a way that its relation to g becomes obvious.This can be achieved with the help of the identity: d r ′′ ∞0dω′′[f 3(r ,r ′′,ω,ω′′)·T ∗(r ′′,r ′,ω′′)+f 4(r ,r ′′,ω,ω′′)·T (r ′′,r ′,ω′′)]==ε0 d r ′′g (r ,r ′′,ω)·χ(r ′′,r ′,ω−i 0)+s (r ,r ′,ω).(B.8)which contains a tensor s (r ,r ′,ω)that arises while avoiding a pole in the complex frequency plane,as we shall see below.Furthermore the right-hand side contains the susceptibility tensor χthat has been defined in (36).In (B.8)the frequency is chosen to be in the lower half of the complex plane just below the real axis.Correspondingly,the term −i 0is an infinitesimally small number on the negative imaginary axis.To prove (B.8)we divide (B.2)by ω′−ω+i 0,with i 0an infinitesimally small imaginary number.The result is:−i ¯h ω′ε01ω+ω′ d r ′′ d r ′′′f 2(r ,r ′′,ω)·˜T∗(r ′′′,r ′′,ω′)·T (r ′′′,r ′,ω′)。
浅谈人性化护理
浅谈人性化护理摘要:随着医学的发展,护理形成自身的发展体系并成为一门举足轻重的学科。
随着医疗重心的转变,社会对人文关怀的需求越来越高。
当代护士不仅仅需要掌握常规的护理操作,还需满足病人的心理需求,以下我们将探讨帕特森和兹德拉德的框架,并浅谈其结构和对关怀理论发展的影响。
关键词人文化护理理论帕特森护理是人类之间的一种经历,作为护士,我们有责任追寻并重申人文主义特征。
护理早已将其实践重点从这些较早的定义转移到其他领域,而不是使用药物或外科手术,并且治疗性康复是这些“补救措施”在疾病治疗中的应用[1]。
Paterson和Zderad 提出的人本主义理论被视为描述性理论,他们与其他理论家一起提出请注意护士与患者之间关系的力量[2]。
这里我们将浅谈Paterson和Zderad 的人本主义理论的理及其临床应用。
1 Paterson和Zderad的概念1.1存在主义苏珊·克莱曼认为存在主义是护士对自己的处境以及相对于身处世界并与他人一起参与项目所做出的选择表示立场并承担责任[3]。
人类的生存的根本:是个人存在和参与不断变化和潜在威胁的世界的经验。
每个具有自我意识的个体都根据与他人以及整个世界的整体中的自我体验来理解。
一个人意识到自我是一个有思想的人,他有希望、信念、恐惧、欲望,寻找目的和意义可以决定一个人行动的意志。
从单一变换的角度来看如果单独或抽象地看待存在的概念就没有意义。
只能从过去、现在的经验整体过程中对特定个体的影响来观察每个人都会因实现自己的必要选择自由,每个人会因不了解自己的选择权而感到焦虑或不适。
焦虑和恐惧通常是人类状态的特征,源于持续的对抗过程,充满了可能性和决策的需要并伴有责任。
沃森将这种单一的转化过程描述为基本的努力并继续提出“每个人都在思想,身体和灵魂之间寻求一种和谐感从而进一步整合,增强和实践真实的自我。
杜威为我们对理解增加了一个维度,从这个角度来看努力可以看作是保持和谐与不和谐之间的张力以及将两者视为自然的一部分或被接受的努力并成为过程。
医护英语水平考试(METS)四级样题试卷及答案
I LISTENING
Part 1
Questions 1 – 10
Questions 1-5 Choose the correct answer, A, B or C.
1 What is a stroke? A It is a loss of blood flow in the brain. B It is a loss of blood flow in the heart. C It is a loss of blood flow in the extremities.
Physical examination: (18) __________ abdomen and icteric sclerae Personal history: no contact with toxic chemicals or clear-water streams, heavy (19) __________ intake of five years’ duration
situation in a couple of other countries
Subjects of the research people under 18 should be excluded focus on men who were in (32) _______________ people who didn‘t have jobs and employed women as a separate (33)
Problems encountered in collecting data a person shopping in town decided to (37) _______________ when it came to the
作文 现象与本质
作文现象与本质英文回答:Phenomena and essence are two fundamental concepts in philosophy and science. A phenomenon is something that is observed or experienced, while an essence is the underlying nature or reality of something. The relationship between phenomena and essence is complex and has been debated by philosophers for centuries.One view is that phenomena are simply appearances,while essence is the true reality. This view is often associated with Plato, who believed that the world of phenomena is a mere shadow of the real world of Forms. Another view is that phenomena and essence are two sides of the same coin. This view is often associated with Aristotle, who believed that phenomena are the manifestation of essence.The relationship between phenomena and essence is alsoimportant in science. Scientists often study phenomena in order to understand the underlying essence of things. For example, a scientist might study the phenomenon of gravity in order to understand the essence of gravity.The distinction between phenomena and essence is not always clear-cut. In some cases, it may be difficult to determine whether something is a phenomenon or an essence. For example, the color of an object is a phenomenon, but the chemical composition of the object is an essence.The relationship between phenomena and essence is a complex and fascinating one. It is a topic that has been debated by philosophers and scientists for centuries, and it is still a topic of active research today.中文回答:现象与本质是哲学和科学中的两个基本概念。
严重的偏科现象的英语作文
严重的偏科现象的英语作文In recent years, the phenomenon of subject bias has become increasingly serious in education systems around the world. Subject bias refers to the tendency of students to excel in certain subjects while struggling in others, leading to an imbalance in their overall academic performance. This issue has significant implications not only for individual students but also for society as a whole.One of the main causes of subject bias is the differing interests and strengths among students. Many students naturally gravitate toward subjects they find enjoyable or intuitive, such as mathematics or literature, while neglecting others like science or foreign languages. This preference can result in a lack of motivation to study subjects that they perceive as difficult or uninteresting.Another contributing factor is the educational system itself. Often, schools place a heavy emphasis on core subjects such as math and science, which can lead students to prioritize these areas over others. Additionally, standardized testing often focuses onspecific subjects, putting further pressure on students to perform well in these areas, rather than fostering a well-rounded education.The consequences of subject bias can be detrimental. Students who excel in certain subjects may receive more encouragement and support, while those who struggle may feel discouraged and disengaged. This can lead to a lack of confidence and a narrow skill set, limiting future educational and career opportunities. Furthermore, a society that values only certain subjects may miss out on the diverse talents and perspectives that individuals with varied strengths can offer.To address the issue of subject bias, several measures can be taken. First, educators should strive to create a more balanced curriculum that values all subjects equally. This includes integrating interdisciplinary approaches that demonstrate the connections between different fields of study. Second, schools should provide additional support for students who struggle in certain subjects, helping them build confidence and skills in areas where they may feel less competent. Finally, fostering a culture of curiosityand exploration can encourage students to engage with a wider range of subjects, allowing them to discover new interests and strengths.In conclusion, the phenomenon of subject bias in education is a significant concern that requires attention from educators, parents, and policymakers. By promoting a more balanced and inclusive approach to learning, we can help students develop into well-rounded individuals, equipped with the diverse skills needed to succeed in an increasingly complex world.中文翻译:近年来,偏科现象在全球教育体系中变得越来越严重。
现象学胡塞尔 英文
现象学胡塞尔英文English: Phenomenology, as developed by Husserl, is a philosophical method that focuses on the study of consciousness and the structures of experience. Husserl aimed to describe phenomena just as they appear, without making any assumptions about their underlying causes or metaphysical implications. He believed that by studying the pure essence of consciousness and experience, we can gain a deeper understanding of the world and our place within it. Husserl's method involves a process of "bracketing" or "epoche," where the philosopher suspends judgment and sets aside any preconceived notions in order to directly attend to the phenomenon at hand. This method allows for a rigorous examination of the structures of consciousness and intentionality, leading to the uncovering of the essential features of experience.中文翻译: 胡塞尔所发展的现象学是一种哲学方法,专注于研究意识和经验的结构。
现象批判英语作文模板
现象批判英语作文模板Phenomenology of Perception。
English Answer:Phenomenology of Perception: A Philosophical Foundation for Psychology。
Phenomenology, a philosophical movement developed by Edmund Husserl in the early 20th century, offers a rigorous and insightful approach to the study of subjective experience. By focusing on the intentional structure of consciousness, phenomenology attempts to elucidate the fundamental nature of perception, consciousness, and the relationship between mind and world.Husserl's phenomenological method involves a process of "bracketing" or "epoché", in which the philosopher suspends judgment and biases to access the pure, unmediated experience of consciousness. This allows for a detailedexamination of the essential structures of experience, such as intentionality, time-consciousness, and the intersubjective nature of human existence.In the realm of perception, phenomenology sheds light on the relationship between the experiencing subject and the perceived object. Husserl argued that perception is not a passive reception of external stimuli, but an active process of meaning-making. The perceiver brings their own subjective interpretations and expectations to the experience, shaping the way they perceive the world.One of the key concepts in phenomenology of perception is the notion of "horizons of perception." These horizons refer to the broader context in which perception occurs, including the perceiver's past experiences, beliefs, and cultural background. These horizons influence the way we perceive objects and events, providing a framework for understanding and making sense of the world.Another important aspect of phenomenology of perception is its emphasis on the role of the body. Husserl arguedthat the body is not merely a passive container for the mind, but an active participant in perception. The body provides the perceiver with a unique perspective and enables them to engage with the world in a meaningful way.Contributions to Psychology。
英语作文 现象法模板
英语作文现象法模板英文回答:Introduction。
Phenomenology, a philosophical approach that emerged in the early 20th century, offers a unique perspective on understanding the world and our experiences within it. Phenomenologists argue that consciousness is the starting point for all understanding, and that by carefully examining and describing our own experiences, we can gain insights into the nature of reality itself. This approach has been applied to a wide range of fields, including psychology, sociology, and philosophy.Core Principles of Phenomenology。
The core principles of phenomenology include:Intentionality: Consciousness is always directedtowards something. We are always aware of the world around us, even if we are not consciously thinking about it.Objectivity and Subjectivity: Phenomenology seeks to bridge the gap between objectivity and subjectivity. It recognizes that our experiences are both subjective and objective, and that both perspectives are essential for understanding the world.Reduction: Phenomenology seeks to reduce our experiences to their essential components. By breaking down our experiences into their smallest parts, we can better understand how they are constructed.Epoche: Phenomenology involves an "epoche," or a bracketing of our assumptions and beliefs. By setting aside our preconceptions, we can more clearly see the world as it is.Methods of Phenomenological Research。
现象学及其效应英语
现象学及其效应英语English Answer:1. Introduction.Phenomenology is a philosophical and psychological movement that emphasizes the first-person perspective and the importance of lived experience. It is based on the idea that all knowledge is rooted in our own subjective experiences and that we can only understand the world through our own perceptions.2. Phenomenological Method.The phenomenological method involves bracketing all assumptions about the world and focusing on the immediate and unmediated experience of things. This is done by suspending judgment and simply describing the things we experience in the moment.3. Phenomenological Reduction.Phenomenological reduction is a process of bracketing or suspending all beliefs and assumptions about the worldin order to get to the pure essence of things. This can be done by imagining a "phenomenological epoché," in which we put all of our beliefs and assumptions in parentheses and simply focus on the things themselves.4. The Phenomenological Subject.The phenomenological subject is the first-person perspective that is the source of all experience. This is not a fixed or unchanging self, but rather a fluid andever-changing stream of consciousness.5. The Phenomenological World.The phenomenological world is the world as it is experienced by the subject. This is not an objective world that exists independently of the subject, but rather a world that is constituted by the subject's own experiences.6. The Phenomenological Attitude.The phenomenological attitude is an attitude of openness and curiosity towards the world. This attitude involves letting go of all preconceived notions and simply experiencing the world as it is.7. Phenomenology in Psychology.Phenomenology has had a significant impact on psychology, leading to the development of qualitative research methods such as phenomenological interviewing and participant observation. These methods allow researchers to gain a deeper understanding of the subjective experiences of individuals.8. Phenomenology in Philosophy.Phenomenology has also been a major influence on philosophy, leading to the development of new philosophical approaches such as existentialism and hermeneutics. Theseapproaches emphasize the importance of the human experience and the need for understanding the world from the perspective of the individual.9. Phenomenology in Other Fields.Phenomenology has also had an impact on other fields such as sociology, anthropology, and literary criticism. In these fields, phenomenology has been used to gain a deeper understanding of the subjective experiences of individuals and the ways in which these experiences shape the social world.10. Conclusion.Phenomenology is a powerful philosophical and psychological approach that has had a significant impact on a wide range of fields. It is a method for understanding the world from the first-person perspective and for gaining a deeper understanding of the subjective experiences of individuals.Chinese Answer:1. 介绍。
如何理解科学是把双刃剑英语作文
如何理解科学是把双刃剑英语作文Title: Understanding Science as a Double-edged SwordScience has been hailed as the beacon of human progress and innovation, leading to groundbreaking discoveries and advancements in various fields. From improving healthcare and nutrition to exploring outer space, the impact of science on society cannot be overstated. However, it is important to recognize that science is a double-edged sword, capable of both positive and negative consequences.On the one hand, science has revolutionized our lives in countless ways. Advancements in medicine have led to longer life expectancy and better quality of life for millions of people around the world. Vaccines, antibiotics, and surgical procedures have eradicated diseases that were once deadly and untreatable. In addition, technology and engineering have enabled us to travel to the moon, communicate across continents in an instant, and access virtually limitless information at our fingertips.Furthermore, scientific research has shed light on the mysteries of the universe and deepened our understanding of the natural world. The discoveries of evolution, genetics, and the laws of physics have transformed our perception of life and theuniverse. By studying the cosmos, we have learned about the origins of the universe and our place in it.However, science also has the potential to be used for harm. The same technology that has improved our lives can also be weaponized and used for destructive purposes. Nuclear weapons, biological warfare, and cyber attacks are all examples of how science and technology can be misused to cause harm and destruction. Moreover, the pursuit of scientific knowledge can sometimes lead to unintended consequences, such as environmental degradation, climate change, and the depletion of natural resources.In addition, scientific advancements have raised ethical and moral dilemmas that society must grapple with. Issues such as genetic engineering, artificial intelligence, and cloning raise questions about the limits of scientific progress and the implications for humanity. For example, the ability to manipulate genes and create designer babies raises concerns about the potential for eugenics and discrimination based on genetics.Ultimately, it is up to society to harness the power of science for the greater good and to mitigate its potential risks. This requires a responsible approach to scientific research and innovation that considers the ethical, social, and environmentalimplications of new technologies. By promoting scientific literacy, critical thinking, and ethical standards, we can ensure that science remains a force for progress and enlightenment.In conclusion, science is a double-edged sword that has the power to transform society for the better or for the worse. By understanding the potential benefits and risks of scientific advancements, we can navigate the complexities of the modern world and ensure that science serves the greater good. As we continue to push the boundaries of knowledge and innovation, let us be mindful of the responsibilities that come with wielding this powerful tool.。
实验现象研究作文英语
实验现象研究作文英语Title: Exploring Experimental Phenomena: An English Essay。
Introduction:In the realm of scientific inquiry, experimental phenomena serve as the bedrock upon which theories arebuilt and tested. Through rigorous observation, experimentation, and analysis, researchers unravel the mysteries of the natural world. In this essay, we delveinto the significance of studying experimental phenomena, its methodologies, and the insights gained through such investigations.Understanding Experimental Phenomena:Experimental phenomena encompass a wide array of observable events that occur under controlled conditions in scientific experiments. These phenomena often challengeexisting theories or raise intriguing questions about the underlying mechanisms governing various processes. By studying these phenomena, scientists aim to elucidate fundamental principles and expand our understanding of the universe.Methodologies in Investigating Experimental Phenomena:The investigation of experimental phenomena relies on systematic methodologies designed to minimize bias and ensure the reliability of results. Experimental designsvary depending on the nature of the phenomenon under study, but they typically involve the formulation of hypotheses,the design of experiments, data collection, and statistical analysis.One commonly used approach is the controlled experiment, where researchers manipulate independent variables while controlling extraneous factors to observe their effects on dependent variables. This method allows for causalinference and helps establish relationships between variables.Another approach involves observational studies, where researchers observe and analyze naturally occurring phenomena without intervening or manipulating variables. While observational studies are valuable for exploring correlations and patterns, they may lack the control of variables inherent in controlled experiments.Insights Gained from Studying Experimental Phenomena:Studying experimental phenomena yields invaluable insights into the workings of the natural world and fosters scientific advancements across various disciplines. Through experimentation, scientists have uncovered principles governing chemical reactions, biological processes, physical phenomena, and psychological phenomena, among others.For instance, the phenomenon of quantum entanglement, where particles become correlated in such a way that the state of one particle instantaneously influences the state of another, has revolutionized our understanding of quantummechanics. This phenomenon has profound implications for fields such as quantum computing and cryptography.Similarly, the study of genetic mutations and their effects on organisms has provided crucial insights into heredity, evolution, and disease. By manipulating genes and observing resulting phenotypic changes, scientists have been able to unravel the genetic basis of numerous traits and disorders.Moreover, investigations into social phenomena, such as conformity and obedience, have shed light on human behavior and societal dynamics. Through carefully designed experiments, researchers have elucidated the factors influencing individual and group behavior, contributing to the fields of psychology, sociology, and organizational behavior.Conclusion:In conclusion, the study of experimental phenomena constitutes a cornerstone of scientific inquiry, drivingdiscovery and innovation across disciplines. By employing rigorous methodologies and fostering curiosity, researchers uncover the mysteries of the universe and advance human knowledge. Through continued exploration and experimentation, we continue to unravel the complexities of nature and unlock the secrets of the cosmos.。
Phenomenology
PhenomenologyPhenomenology is the study of structures of consciousness as experienced from the first-person point of view. The central structure of an experience is its intentionality, its being directed toward something, as it is an experience of or about some object. An experience is directed toward an object by virtue of its content or meaning (which represents the object) together with appropriate enabling conditions.现象学是对从第一人称角度所体验的意识结构的研究。
体验的中心结构是它的意向性,它总是指向某物,当它是一个体验或关于某一客体。
一个体验直接指向一个对象是由于它的内容或意义(代表这个物体)加上适当的授权条件。
Phenomenology as a discipline is distinct from but related to other key disciplines in philosophy,such as ontology, epistemology, logic, and ethics. Phenomenology has been practiced in various guises for centuries, but it came into its own in the early 20th century in the works of Husserl,Heidegger, Sartre, Merleau-Ponty and others. Phenomenological issues of intentionality,consciousness, qualia, and first-person perspective have been prominent in recent philosophy of mind.现象学区别于但又与其它哲学的学科相联系,例如本体论,认识论,逻辑学和伦理学。
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Phenomenological study of the double radiative decay B → K γγ
PoS(HEP2005)277
Gudrun Hiller
Institut für Physik, Universität Dortmund, D-44221 Dortmund, Germany E-mail: ghiller@physik.uni-dortmund.de
PoS(HEP2005)277
∗ where λt = VtbVts and p(p′ ) represents the momentum of the b(s)-quark. We denote by k1 , k2 µν µν the 4-momenta and by ε (k1,2 ) the polarization vectors of the photons. The tensors W2 and W7 exhibit the contribution of the four-fermion operators O1,2 ≃ (sγµ Lc)(cγ µ Lb) and the photon dipole ¯ ¯ operator O7 ∼ sσµν F µν Rb, respectively, and are given together with the loop function κc in [1]. ¯ In this work we consider the exclusive B → K γγ decay. Since its matrix element induced by O7 is non-local, it is difficult to estimate model-independently. Previous works [3,4] used here solely vector meson dominance models. Instead, we use OPE techniques, which allow to i make the matrix element local in a specific kinematic region by choosing appropriate photon energies and then ii express the matrix element in terms of known form factors. Specifically, we demand both the internal s- and b-quarks to be far off-shell, with virtualities of order mb . For example, if both photons have energies mb /3, then the intermediate propagators of the 1PR diagrams (Qs )2 = 1,2 √ (p′ + k2,1 )2 and (Qb )2 = −((p − k1,2 )2 − m2 ) equal mb / 3 and mb 2/3, respectively. Then we 1,2 b integrate out large scales of order mb . We construct the vertices in the effective theory out of a bottom heavy HQET quark hv and a strange collinear SCET quark χ [5,6]. Here, v = pB /mB and a light-like vector n = pK /EK , where EK , pK denotes the energy, 4-momentum of the kaon. Hence, we perform an OPE in ΛQCD /Q, where Q = {mb , EK , Qs,b , q2 } and q2 = (k1 + k2 )2 . 1,2 For the lowest order matching onto the b → sγγ amplitude, we obtain after using the equations of motion the following dimension 8 operators [1]
A. Salim Safir∗
CERN, Department of Physics, Theory Unit, CH-1211 Geneva 23, Switzerland E-mail: safir@mail.cern.ch Using the operator product expansion (OPE) technique, we study the rare double radiative decay B → K γγ in the Standard Model (SM) and beyond. We estimate the short-distance (SD) contribution to the decay amplitude in a region of the phase space which is around the point where all decay products have energy ∼ mb /3 in the rest frame of the B-meson. At lowest order in 1/mb , the B → K γγ matrix element is then expressed in terms of the usual B → K form factors known from semileptonic rare decays. The integrated SD branching ratio in the SM in the OPE region turns out to be ∆B(B → K γγ )OPE ≃ 1 × 10−9. We work out the di-photon invariant mass distriSM bution with and without the resonant background through B → K{ηc , χc0 } → K γγ . In the SM, the
mb ¯ χσµν σαβ Rhv F1αβ F2µν , 4
µν αβ ¯ − 2imb χσµν Rhv F1 F2 vα nβ ,
˜ ¯ χγ µ Lhv F1αβ Dα F2 β µ + (1 ↔ 2)
˜ where Fµν = 1/2εµναβ F αβ and Wilson lines are understood in χ . The B → K γγ matrix elements are then obtained from tree level matching of the QCD onto the SCET currents [5,7,8] as ¯ K(n)|χ hv |B(v) = 2EK ζ (EK ), ¯ K(n)|χσµν hv |B(v) = −2iEK ζ (EK ) vµ nν − vν nµ , (2)
International Europhysics Conference on High Energy Physics July 21st - 27th 2005 Lisboa, Portugal
∗ Speaker.
c Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.
resonance contribution is dominant in the region of phase space where the OPE is valid. On the other hand, the present experimental upper limit on Bs → τ + τ − decays, leaves considerable room for New Physics (NP) in the one-particle-irreducible contribution to B → K γγ decays. In this case, we find that the SD B → K γγ branching ratio can be enhanced by one order of magnitude with respect to its SM value and the SD contribution can lie outside of the resonance pe(v) = 2EK ζ (EK )nµ ,
¯ K(n)|χσµν γ5 hv |B(v) = −2EK ζ (EK )εµναβ vα nβ ,
where the form factor ζ (EK ) can be identified with the QCD form factor in the usual parametrization, as ζ = f+ . It is the only form factor remaining in the symmetry limit, known e.g. from studies in B → Kℓ+ ℓ− decays. Analytical formulae for the B → K γγ amplitude from the OPE are given in [1]. An additional contribution to B → K γγ beyond the OPE is photon radiation off the spectator. It is either kinematically excluded (soft gluons between active quarks and spectator) or suppressed 277 / 2