a r X i v :h e p -p h /0509254v 2 20 J u n 2006
SHEP-05-07February 2,2008
Weak e?ects in proton beam asymmetries
at polarised RHIC and beyond
S.Moretti,M.R.Nolten and D.A.Ross
School of Physics and Astronomy,University of Southampton
High?eld,Southampton SO171BJ,UK
Abstract
We report on a calculation of the full one-loop weak corrections through the order α2S αW to parton-parton scattering in all possible channels at the Relativistic Heavy Ion Collider (RHIC)running with polarised pp beams (RHIC-Spin).This study extends the analysis previously carried out for the case of 2→2subprocesses with two external gluons,by including all possible four-quark modes with and without an external gluon.The addi-tional contributions due to the new four-quarks processes are extremely large,of order 50to 100%(of either sign),not only in the case of parity-violating beam asymmetries but also for the parity-conserving ones and (although to a more limited extent)the total cross section.Such O (α2S αW )e?ects on the CP-violating observables would be an as-tounding 5times larger for the case of the LHC with polarised beams –which has been discussed as one of the possible upgrades of the CERN machine –whereas they would be much reduced for the case of the CP-conserving ones as well as the cross section.
Keywords:Electroweak physics,Parity violation,Polarised pp scattering,RHIC
The purely weak component of Electro-Weak(EW)interactions is responsible for inducing parity-violating e?ects in jet observables,detectable through asymmetries in the cross section, which are often regarded as an indication of physics beyond the Standard Model(SM)[1]. These e?ects are further enhanced if polarisation of the incoming beams is exploited,like at the BNL machine mentioned in the abstract[2,3].There have also been some discussions [4,5]on the idea of polarising the proton beams at the Large Hadron Collider(LHC)as one of the possible upgrades of the CERN machine,though no proposal has been put forward yet.At either machine,comparison of theoretical predictions involving parity-violation with experimental data can be used as a powerful tool for con?rming or disproving the existence of some beyond the SM scenarios,such as those involving right-handed weak currents[6], contact interactions[7]and/or new massive gauge bosons[8,9,10].
In view of all this,it becomes of crucial importance to assess the quantitative relevance of weak e?ects entering via O(α2SαW)the?fteen possible2→2partonic subprocesses responsible for jet production in hadronic collisions1,namely:
gg→qˉq(1)
qˉq→gg(2)
qg→qg(3)
ˉq g→ˉq g(4)
qq→qq(5)
ˉqˉq→ˉqˉq(6)
qQ→qQ(same generation)(7)
ˉqˉQ→ˉqˉQ(same generation)(8)
qQ→qQ(di?erent generation)(9)
ˉqˉQ→ˉqˉQ(di?erent generation)(10)
qˉq→qˉq(11)
qˉq→QˉQ(same generation)(12)
qˉq→QˉQ(di?erent generation)(13)
qˉQ→qˉQ(same generation)(14)
qˉQ→qˉQ(di?erent generation),(15) with q and Q referring to quarks of di?erent?avours,limited to u-,d-,s-,c-and b-type(all taken as massless).While the?rst four processes(with external gluons)were already computed in Ref.[3],the eleven four-quark processes are new to this study2.Besides,these four-quark processes can be(soft and collinear)infrared divergent,so that gluon bremsstrahlung e?ects ought to be evaluated to obtain a?nite cross section at the considered order.In addition,for completeness,we have also included the non-divergent2→3subprocesses
qg→qqˉq(16)
ˉq g→ˉqˉq q(17)
qg→qQˉQ(same generation)(18)
ˉq g→ˉqˉQQ(same generation).(19)
√
By recalling that at the typical RHIC-Spin energies(e.g.,
s=14TeV),gluon-induced processes are largely dominant,particularly at low Bjorken?x. As for what concerns the processes with external gluons,it is worth noticing that no CP-violation occurs at tree-level,so that O(α2SαW)is the?rst non-trivial order at which parity violation is manifest.Regarding four-quark processes,the following should be noted.Parity-violating contributions to channels(5)–(15)are induced already at tree-level,through O(α2EW). Besides,all four-quark channels also exist through the CP-violating O(αSαEW)[11],although subprocesses(9),(10),(13)and(15)only receive Cabibbo-Kobayashi-Maskawa(CKM)sup-pressed contributions at this accuracy(i.e.,they mainly proceed via CP-conserving O(α2S) interactions).Furthermore,notice in general that through O(α2SαW)there are many more diagrams available for channels(1)–(15)than via O(α2S)or indeed O(αSαEW)and O(α2EW). Therefore,in terms of parton luminosity,simple combinatorics and power counting,one should expect the impact of O(α2SαW)terms to be large,certainly in parity-violating observables and possibly in parity-conserving ones as well.This is what we set out to test in this paper3for the case of RHIC and LHC.(See Refs.[12,13]for an account of these e?ects at Tevatron.) Before proceeding further we ought to clarify at this stage that we have only computed purely weak e?ects at one-loop level through O(α2SαW),while in the case of tree-level processes via O(αSαEW)and O(α2EW)also the Electro-Magnetic(EM)contributions are included(and so are the interference e?ects between the two).This is why we are referring in this paper to the purely weak terms by adopting the symbolαW,while reserving the notationαEW for the full EW corrections.Here then,we will haveαW≡αEM/sin2θW(withαEM the Electro-Magnetic(EM)coupling constant andθW the weak mixing angle)whileαEW will refer to the appropriate composition of QED and weak e?ects as dictated by the SM dynamics.
We have not computed one-loop EM e?ects for two reasons.Firstly,their computation would be technically very challenging,because the photon in the loop can become infrared(i.e., soft and collinear)divergent,thus requiring also the inclusion of photon bremsstrahlung e?ects, other than of gluon radiation.Secondly,O(α2SαEM)terms(in the above spirit,αEM signi?es here only the contribution of purely EM interactions)would carry no parity-violating e?ects and their contribution to parity-conserving observables would anyway be overwhelmed by the well known O(α3S)terms[14](see also[15,16]).However,notice that we are not including these next-to-leading order(NLO)QCD corrections either,as we are mainly interested in parity-violating beam asymmetries.
Since we are considering weak corrections that may be identi?ed via their induced parity-violating e?ects and since we wish to apply our results to the case of polarised proton beams,it is convenient to work in terms of helicity Matrix Elements(MEs).Here,we de?ne the helicity
amplitudes by using the formalism discussed in Ref.[17].At one-loop level such helicity amplitudes acquire higher order corrections from:(i)self-energy insertions on the fermions and gauge bosons;(ii)vertex corrections and(iii)box diagrams.The expressions for each of the corresponding one-loop amplitudes have been calculated using FORM[18]and checked by an independent program based on FeynCalc[19].Internal gauge invariance tests have also been performed.The full expressions for the contributions from these graphs are however too lengthy to be reproduced here.
As already mentioned,infrared divergences occur when the virtual or real(bremsstrahlung) gluon is either soft or collinear with the emitting parton and these have been dealt with by using the formalism of Ref.[20],whereby corresponding dipole terms are subtracted from the bremsstrahlung contributions in order to render the phase space integral free of infrared divergences.The integrations over the gluon phase space of these dipole terms were performed analytically in d-dimensions,yielding pole terms which cancelled explicitly against those of the virtual graphs.There remains a divergence from the initial state collinear con?guration, which is absorbed into the scale dependence of the Parton Distribution Functions(PDFs)and must be matched to the scale at which these PDFs are extracted.Recall that the remnant initial state collinear divergence at O(αS)is absorbed by the LO Q2dependence of the PDFs. Therefore,to O(α2SαW),it is su?cient,for the purpose of matching these divergences,to consider the LO PDFs.It is also consistent to use the values of the runningαS obtained form the one-loopβ-function.In order to display the corrections due to genuine weak interactions the same PDFs and strong coupling are used in the LO and NLO observables.
The self-energy and vertex correction graphs contain ultraviolet divergences that have been subtracted here by using the‘modi?ed’Dimensional Reduction(
DR,as opposed to the more usual‘modi?ed’Minimal Subtraction (
DR scheme whereas the EM coupling,αEM,has been taken to be1/128at the above subtraction point.The one exception to this renormalisation scheme has been the case of the self-energy insertions on external fermion lines,which have been subtracted on mass-shell,so that the external fermion?elds create or destroy particle states with the correct normalisation
The top quark entering the loops in reactions with external b’s has been assumed to have mass m t=175GeV and widthΓt=1.55GeV.The Z mass used was M Z=91.19GeV and was related to the W-mass,M W,via the SM formula M W=M Z cosθW,where sin2θW=0.232. (Corresponding widths wereΓZ=2.5GeV andΓW=2.08GeV.)For the strong coupling constant,αS,we have used the one-loop expression withΛ(n f=4)
Figure1:The dependence of the cross section as well as of the beam asymmetries on the jet
transverse energy at tree-level(large frames)and the size of the one-loop weak corrections(small
√
frames),at the two RHIC-Spin energies
s=200and500GeV are also given.
A P V dσ≡dσ???dσ++.(20) The?rst is parity-conserving while the last two are parity-violating4.
Figs.1shows the size of the O(α2SαW)e?ects relatively to the well known LO results, the latter being de?ned as the sum of all O(α2S),O(αSαEW)and O(α2EW)contributions,for the case of RHIC,for two reference energies.Both the di?erential cross section and the above beam asymmetries are plotted,each as a function of the jet transverse energy.The
O(α2SαW)corrections are already very large at cross section level,by reaching?5(?9)%at √
s=300(600)GeV.In the case of both A L and A P V,in regions away from the threshold at E T≈M W/4(where resonance e?ects emerge),there is no local maximum for positive or negative corrections,as both grow monotonically to the level of+100%(at low E T)and?50 to?70%(at high E T and with increasing collider energy).All such e?ects should comfortably
be observable at RHIC,for the customary values of integrated luminosity,of200and800pb?1,√
in correspondence of
4In the numerical analysis which follows we will assume100%polarisation of the beams.
Figure2:The dependence of the cross section as well as of the beam asymmetries on the jet transverse energy at tree-level(large frames)and the size of the one-loop weak corrections(small
√
frames),at the LHC energy
s=14TeV),the O(α2SαW) corrections to the total cross section as well as the CP-conserving asymmetry are reasonably under control.In fact,they grow monotonically and reach the≈?3%and≈4%at the kinematic limit of the jet transverse energy(as de?ned by the PDFs),respectively.However, it is debatable as to whether these e?ects can actually be disentangled,as we expect systematic experimental uncertainties to be of the same order.Away from the threshold at E T≈M W/2, O(α2SαW)e?ects onto the parity-violating asymmetries are instead enormous,as they yield a K-factor increasing from?2to?4.5,as E T varies from80to500GeV.Despite the absolute value of the CP-violating asymmetries is rather small in the above interval,the huge LHC luminosity(10fb?1per year should be feasible for,say,a70%polarisation per beam[23]) would render the above higher order corrections manifest.
It is intriguing to understand the di?erent behaviours of the O(α2SαW)e?ects depending on the observable and the collider being considered.To this end,we have presented in Tabs.1–2 the contributions to the E T dependent cross section of subprocesses(1)–(15)through O(α2SαW) separately,at both RHIC-Spin and LHC.The purpose of these tables is to illustrate that the leading partonic composition of the O(α2SαW)corrections is markedly di?erent at the two machines.While at RHIC the key role is played by subprocess(7),at the LHC the conspicuous rise of the gluon-luminosity enhances in turn the yield of channel(3)to a level comparable
to that of mode(7)5.(The hierarchy among the subprocesses seen in Tabs.1–2,for?xed jet transverse energy,is characteristic across most of the available E T range at both colliders.) The O(α2SαW)corrections are particularly large for subprocesses(7)–(8)and(12),mainly in virtue of the large combinatorics involved at loop level(as intimated earlier),with respect to the LO case.
Table1:The contributions of subprocesses(1)–(15)to orderα2SαW with respect to the full LO
√
result for the total cross section at RHIC-Spin,at E T=70GeV for
s=600GeV.Here,we have paired together the channels with identical Feynman diagram topology.We use GSA as PDFs andμ=E T/2as factorisation/renormalisation scale.Column(a)is the percentage contribution from the O(α2SαW)corrections,column(b)is the percentage correction to the tree-level partonic subprocess and column(c)is the percentage contribution at the tree-level of that partonic subprocess to the di?erential cross section at the relevant E T.
√s=600GeV Subprocess
(a)(c)(a)(c)
gg→gg 1.35 1.17
0.0267–0.179
(2) 4.72E-050.188–0.0003310.184
–0.0589–0.264
(5)–(6)–0.41146.1–1.4247.1
–6.64–14.7
(9)–(10)0.0003930.718–0.006020.711
–0.252–0.714
(12)0.006640.06130.01460.0571
1.23 1.17
(14)0.0406 1.280.0282 1.25
0.0491–0.803
qq′→QQ′orˉqˉq′→ˉQˉQ′0.007100.0148 Total–1.94–5.11
The di?erent behaviours seen in Figs.1–2can easily be interpreted in terms of the LO contributions.In this respect,as already mentioned,Tabs.1–2clearly make the point that the jet phenomenology at RHIC-Spin is dominated by subprocesses initiated by quarks only while at the LHC gluons-induced channels are generally predominant.At RHIC energies,LO pro-duction through orderα2S is dominated by channel(5)whereas at the LHC the overwhelmingly dominantα2S channels are gg→gg(which is not subject to O(α2SαW)corrections,as already mentioned)and subprocess(3).Besides,channel(5)through O(α2S)is mainly concentrated
Table2:The contributions of subprocesses(1)–(15)to orderα2SαW with respect to the full LO
√
result for the total cross section at LHC,at E T=300GeV for
s=14TeV
(a)(c)
gg→gg41.9
–1.25
(2)–0.003860.228
–0.711
(5)–(6)–0.112 1.70
–17.3
(9)–(10)–0.03300.926
–1.85
(12)0.04660.0540
–1.50
(14)0.0131 1.196
–2.64
qq′→QQ′orˉqˉq′→ˉQˉQ′0.0221
Total–1.075
at low E T while with growing E T the O(αSαEW)and–particularly–O(α2EW)terms gain in relative importance.Furthermore,O(α2S)terms entering channel(5)do not contribute, obviously,to the parity-violating asymmetries.Therefore,it should not be surprising to see at RHIC-Spin that our corrections are very large in the case of the latter,where the LO term is O(αSαEW),respect to which the corrections computed here are suppressed only by one power ofαS.We attribute instead the size of the O(α2SαW)e?ects on the cross section and the parity-conserving asymmetry again to the fact that through O(α2SαW)there are many more diagrams available for such channels than via O(α2S)or indeed O(αSαEW)and O(α2EW).As for the LHC,the fact that gg→gg and subprocess(3)vastly dominates through O(α2S)the dσ/dE T distribution explains why O(α2SαW)corrections are limited to the percent level.In A LL,which has no gg→gg component,O(α2SαW)e?ects become somewhat more visible in comparison.
Furthermore,in the case of the LHC,one should note the monotonic rise of the corrections with increasing jet transverse energy,for all observables studied,which can be attributed to the so-called Sudakov(leading)logarithms[24,25]of the formαW log2(E2T/M2W),which appear
in the presence of higher order weak corrections.These‘double logarithms’are due to a lack
of cancellation of infrared(both soft and collinear)virtual and real emission in higher order contributions due to W-exchange,arising from a violation of the Bloch-Nordsieck theorem
occurring in non-Abelian theories.(In fact,if events with real Z radiation are vetoed in the jet sample,αW log2(E T/M2Z)terms would also a?ect the corrections[12].)Clearly,at LHC energies,E T can be very large,thus probing the kinematic regime of these logarithmic
e?ects,which instead a?ected RHIC only very https://www.doczj.com/doc/1610838381.html,bine then the e?ects of such large logarithms with the fact that A L and A P V receive no pure QCD contributions,and one can
explain the enormous(and increasing with E T)O(α2SαW)corrections to these two observables. In fact,recall that another way of viewing the O(α2SαW)terms computed here is as?rst order QCD corrections to the O(αSαW)terms,which are the leading order contributions to A L and
A P V.From this perspective then,the large results reported here can be understood as large O(αS)corrections.Furthermore,also recall here the following two aspects,already mentioned. Firstly,there are several partonic processes which are CKM suppressed at O(αSαEW)but
which occur without CKM suppression at O(α2SαW).Secondly,processes involving external gluons and weak interactions occur for the?rst time at O(α2SαW).
As one of the purposes of polarised colliders is to measure polarised structure functions, in the ultimate attempt to reconstruct the proton spin,it is of some relevance to see how the O(α2SαW)results obtained so far for GSA compare against GRSV-STN.This is done
in Figs.3–4,where we have also adopted the di?erent choiceμ=E cm(E T)as factorisa-
√
tion/renormalisation scale,i.e.,the centre-of-mass energy at parton level
s=200and500GeV,is straightforward.As expected,these results do not di?er
dramatically from those obtained for300and600GeV,respectively.Fig.1also shows the size of the corrections at these two additional energies,for our usual observables and default choice of PDFs and factorisation/renormalisation scale.For the purpose of emulating the e?ects of O(αSα2W)terms at whichever collider and energy,we make available our code on request.
Figure3:The dependence of the corrections to the cross section as well as the beam asymmetries on the jet transverse energy for two sets of PDFs,GSA and GRSV-STN,at the two RHIC-Spin energies
√
Figure4:The dependence of the corrections to the cross section as well as the beam asymme-tries on the jet transverse energy for two sets of PDFs,GSA and GRSV-STN,at the LHC energy
√
[17]E.Maina,S.Moretti and D.A.Ross,JHEP0304(2003)056.
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503].
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[23]A.De Roeck,private communication.
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[26]S.Moretti and D.A.Ross,in progress.
…Back to Sleep?: Why Are 2,500 U.S. Babies Still Dying of SIDS Each Year? ‘用背部睡觉’：为什么美国每年都有2500个婴儿死于婴儿猝死综合症 Putting babies on their back to sleep has dramatically reduced the number of SIDS deaths, but thousands of babies still die each year. A look at the key risk factors. 让婴儿用背部睡觉戏剧性的减少了婴儿猝死综合症的死亡数量，但每年还是有上千数量的婴儿死亡。这有一种对于关键的风险因素的看法。 There?s no doubt that the Back to Sleep campaign launched in 1994 to get parents to stop putting babies to sleep on their tummies has been a success. In the 1970s and 1980s, the rate of infant deaths per 1,000 live births was 1.5; it?s now 0.5. 无需置疑的是，1994年发起的用背部睡觉的运动，旨在阻止父母让婴儿用肚子睡觉是成功的。在20世纪70到80年代，婴儿死亡率为每一千名安全出生婴儿中有1.5，现在是0.5。 Within a generation, most babies are now put to bed on their backs, and yet 2,500 U.S. infants still die each year in the U.S. Researchers trying to understand why have noticed a curious byproduct of the trend toward back-sleeping: as fewer babies were being put to sleep on their bellies, more babies were documented engaging in other pediatric no-nos — sleeping with their parents, for example — which is another risk factor for SIDS. 在一代人中，大部分婴儿现在都用背部放在床上，但美国每年依然有2500个婴儿死亡。研究员正试图弄明白为什么人们会注意到用背部睡觉这种趋势的奇怪的副产品：越来越少的婴儿用腹部睡觉，越来越多的婴儿被证明参与到了一些儿科禁止的事情中——例如，和父母一起睡——这是婴儿猝死综合症的另一个风险因素。 A study published Monday in the journal Pediatrics takes a look at how risk factors for SIDS have evolved over the years. In an analysis of the 954 babies who died suddenly and unexpectedly in San Diego County between 1991 and 2008 — 568 of these deaths were attributed to SIDS — researchers found that
大学生毕业晚会主持词 A：青春是一曲荡气回肠的歌，三年前我们怀着彩色梦想走进了鄂大，三年中我们有过欢笑，流过泪水，经历磨炼，得到成长 B：三年后的今天，我们在这里重温青春过往，因为明天就将各奔天涯。也正因为此，今夜，我们承载了太多的祝福与惦念，寄托了太多的关怀与企盼。 C：今晚，让我们再一次重温，那些感动过我们的人和事：灯火通明的教学楼里用功的身影，篮球场上捍卫集体尊严的男儿霸气，满是欢声笑语的宿舍边不着边际的闲谈…… D：又一个三年轮回之后，在同样微凉的夏夜，你是否会记起校园里的梧桐树，你是否会记起日记本里的书签，那些五彩缤纷的日子？ A：无数个三年之后，你们的思念是否会有增无减？在你成长的岁月里，在你闯荡社会的每一天，是否会有那么几个瞬间让你渴望回到过去 B：让我们静静享受一下挑战，在日复一日与时间的赛跑中，你会变得更加坚强，更加神采奕奕！又一个青春之旅从今晚启航，又一个光阴的故事在今晚讲述 C：亲爱的同窗，不要带着离别的愁绪，因为明天又是一个新的起点，因为我们相信再次相逢，我们还是一首动人的歌！D：很高兴今天能有这个机会同大家相聚一堂，共叙离别。就让今天铭刻在我们心间，让母校留住我们的风采！ A：今天，我们也非常荣幸的请到了…… B：下面让我们用热烈的掌声有请……上台讲话 结束语A：欢快的舞蹈表达不尽我们对母校的敬意 B：热情的赞歌唱不尽我们对母校的一腔深情
C：流火的六月，我们将带着恩师的叮咛，怀着必胜的信心，走向新的征程 D：绚烂的七月，我们将载着母校的祝愿，带着亲人的希望，向着新的征程扬帆起航A：老师们，同学们，欢送10级毕业生联欢晚会合：到此结束 A李：毕业，是一个沉重的动词； 刘：毕业，是一个让人一生难忘的名词； 李：毕业，是感动时流泪的形容词； 刘：毕业，是当我们以后孤寂时候，带着微笑和遗憾去回想时的副词； 李：毕业，是我们夜半梦醒，触碰不到而无限感伤的虚词。 刘：若干年后，假如我们还能够想起那段时光，也许这不属于难忘，也不属于永远，而仅仅是一段记录了成长经历的回忆。 李：尊敬的各位领导老师 刘：亲爱的各位同学们 合：大家晚上好！ 李：很荣幸和大家相聚在这激情如火的六月，在这充满忧伤的六月！ 刘：很高兴和大家相聚在“放心去飞，20年后再相聚—毕业晚会”现场！ 李：我是李扬 刘：我是刘伟清 李：今天晚会现场非常荣幸的邀请到院系的各位领导和老师们。 刘：让我们首先欢迎…… 李：灿烂的星空曾经铭刻你我的笑容
2012年1月4日星期三 雌激素是新的“利他林”吗？ ——性激素能让一部分女性思维敏捷，却也让一部分迟钝 大考即将来临？无法集中注意力？尝试一点雌激素吧。 加州大学伯克利分校的神经系统科学家在最近的一项研究中报道称，女性生理周期中的荷尔蒙波动可能会如咖啡因、甲基苯丙胺或最常见的兴奋剂利他林一样影响其大脑。 近年来的研究表明，工作记忆（短期信息处理能力）是依赖于化学物质多巴胺的。事实上，像利他林这样的药物可以模仿多巴胺帮助人们集中注意力。在老鼠身上的研究显示，雌激素似乎可以诱发多巴胺的释放。但是伯克利这次的新研究是首次把认识能力和人的雌激素水平联系起来，这也就解释了为什么有些女性会在她们生理周期的不同时间点有着或好或坏的认识能力。 这只研究团队对24名健康女性进行了检测。通过基因测试，她们中有些天然多巴胺水平高，而有些天然低。不出所料，多巴胺水平低的女性对于处理复杂的工作记忆问题有困难，比如将一串五个数字反着背出来。但当测试在排卵期中进行，雌激素水平最高时（一般是月经期的10~12天后）这些女性的表现显著改善，有大约10%的进步。令人惊讶的是，多巴胺水平天然高的女性处理复杂问题的能力，却在排卵期中雌激素水平最高的时候有很明显的下降。 根据组织此次研究的Ph.D Emily Jacobs说，脑中的多巴胺是“classic Goldilacks scenario”。对于多巴胺水平最低的25%女性来说，在月经期多巴胺水平的增加会增强她们的认识能力，而对于多巴胺水平最高的25%女性来说，月经期多巴胺水平的增加可能会使她们的多巴胺水平超过一个上限，从而减弱她们的认识能力。而剩下的50%女性都处在这两类女性水平之间，不在研究的范围内。 这项研究有着重大的意义。Jacob说，像咖啡因、利他林这种诱发多巴胺释放的药物对于特定时期的女性是无效，甚至是损害性的。而且，她还希望提醒科学家们注意，在研究脑部疾病时，男女大脑虽然天赋相同但是并不完全一样。 Jacob说，这之间有很大区别，只有我们能知道他们在正常状态下的区别，我们才能预测他们在疾病状态下的区别。 毁约——脑扫描揭示誓言什么时候会不被遵守 新郎说“我愿意”而又和别人有一腿的时候，他脑中发生了什么？朋友承诺还钱却一直不还，他的脑中又发生了什么？一项最新研究显示，毁约是一项很复杂的神经生物学事件。而且脑扫描可以在毁约发生前预测出谁将要毁约。 瑞士苏黎世大学的科学家运用核磁共振技术把大脑比喻成了一场投资游戏。投资者必须决定是否承诺与受托者分享利益。如果投资，会使得账户中的资金增加，但如果受托者选择不分享，结果也会是投资者受损失。几乎所有投资者都说会把钱给受托者，但最后并不会所有人都守约。 通过核磁共振的扫描，研究者可以在他们有机会毁约前预测出他们会不会毁约。毁约者脑部的一些区域的活动会更加活跃，包括分管在压抑诚实回应时自我控制的前额皮质层，和标志
英语翻译 Unit 1Book 3. 中国传统节日以中国的农历为依据。农历年的岁首称为春 节，俗称“过年”，有祈年等多种习俗，是中国人民最隆重的传统节日， 象征团结兴旺。其他主要的节日有元宵节、清明节、端午节、七夕节、 中秋节、重阳节、冬至节、腊八节等等。各个节日都有其来源讲究和风 俗习惯。农历节日与农历中的二十四节气不同。农历节日是中华民族凝 聚力和生命力的体现 Traditional Chinese festivals are usually fixed to the Lunar calendar. January 1st on the lu Seventh Festival, the Mid-Autumn Festival, the Double- Ninth Festival, the Winter Solstice, and the Eight Day of the Twelfth Lunar Month, etc. Ea Lunar calendar. They embody China's cohesion and vitality. Unit 3Book3. 中国古代四大艺术“琴棋书画” 的画特指国画。其绘画形式 是用毛笔蘸水、墨、颜料作画于绢、帛、宣纸之上，古代称之为水墨丹 青。为区别于西方的油画而称之为“中国画”，简称“国画”。其题材有人 物、山水、花鸟等。技法可分为工笔和写意。国画的艺术特质在于“笔 墨”，强调以形写神，画尽意在。国画在艺术创作上反映了中化民族的 审美意识和情趣。 The four art forms in ancient China are guqin, chess, penmanship, and painting. And paint painting.” In order to distinguish it from Western oil-paintings, the Chinese people term their works “traditional Chinese painting” ( hand brushwork. The artistic characteristics lie in “the writing brush and ink.” Chinese pai 5. 中国石窟 中国石窟组要反映的是佛教文化艺术。敦煌莫高窟、大同云冈石窟、洛 阳龙门石窟、天水麦积山石窟，号称中国四大石窟艺术景观。佛教石窟 随山雕凿、彩绘，形象生动自然，将崇尚美与世俗情融为一体，把天然 造化与人工创造有机结合，是由建筑、绘画、雕塑等组成的博大精深、 绚丽夺目的综合艺术殿堂。其艺术成就为世界瞩目，已成为重要的世界 文化遗产。 Chinese Grottoes Chinese grottoes mainly reflect the art of Buddhist culture. In China， there are four major art landscape of grottoes:the Mogao Grottoes at Dunhuang, the Yungang Grottoes at Datong, the Longmen Grottoes at Luoyang, and the Maijishan Grottoes at Tianshui. Carved and painted on mountains, the Buddhist grottoes mingle both sublimity and secular feelings together, presenting us a vivid and natural appearance. They embody the systematic combination of both the exceptional artistry of great nature and the extremely fine craftsmanship of mankind. The Chinese Buddhist Grottoes are regarded
圭亚那盆地地层时代中英文对照 Cainozoic 新生界 Tertiary 第三纪 Pleistocene 第三纪更新世 Miocene 第三纪中新世 Lower Miocene 第三纪下中新世 Oligocene 第三纪渐新世 Eocene 第三纪始新世 Middle Eocene第三纪中始新世 Lower Eocene第三纪下始新世 Paleocene 第三纪古新世、古近系 Cretaceous 白垩纪 Senonian 森诺阶 Campanian 坎帕阶 Santonian 桑托阶 Coniacian 科尼亚克阶（晚白垩纪第三期）Turonian 白垩纪土仑阶（晚白垩纪第二期）Cenomanian 森诺曼阶 Albian 阿尔比阶 Aptian 阿普第阶 Barremian 巴列姆阶 Precambrian 前寒武纪地层
Cainozoic 新生界 Quaternary 第四系Quaternary period 第四纪Paleocene 第三纪古新世、古近系 Mesozoic中生界 Cretaceous 白垩系 Jurassic 侏罗系 Triassic 三叠系 LateTriassicepoch 晚三叠世 Paleozoic 古生界 Permian 二叠系 LatePermianepoch Early Permian 早二叠世 Carboniferous 石炭系石炭纪 Late Carboniferous Devonian 泥盆系泥盆纪upperDevonionseries 上泥盆统 siluric 志留系Silurian 志留纪 Ordovician 奥陶系奥陶纪 Cambrian 寒武系寒武纪 Proterozoic era 元古代
湘艺版五年级音乐《长白山下的歌谣》 教学设计 《长白山下的歌谣》教学设计 教材版本：湘艺版音乐教材 教学对象：五年级上期 一、教学案例： （一）题：《长白山下的歌谣》音乐综合 （二）教材版本：湘版新标实验教材 （三）年级：五年级 （四）教具准备：钢琴、AI、打击乐器、朝鲜族服饰、长鼓、金达莱花。 （五）教学目标： ①、认知目标：认真听赏朝鲜民歌《道拉基》，学习三拍子节奏特点。 ②、能力目标：通过小组合作学习（设计身势节奏、用长鼓为歌曲伴奏、即兴歌舞等形式）培养学生的创新能力、合作能力，体验朝鲜族民歌的韵律。 ③、情感目标：通过感受性学习歌曲《金达莱花开朵朵红》，了解朝鲜族人民勤劳淳朴、团结互助、热情好客、能歌善舞的优良传统与民族风情。 （六）设计思路： 五十六个民族五十六枝花，生活在吉林省长白山脚下的
朝鲜族，其歌舞有着独特的节奏韵律。湘版新标实验教材五年级上册第八单元题为：《长白山下的歌谣》，它引起了我的研究兴趣。本单元的教育主题为：用民族音乐激发学生的爱国情感，实现多元文化的交流。即：通过音乐去感受民族文化，进而去了解民族文化；反之，通过文化，我们才可以去体验民族音乐，整体地去认识民族音乐。本时选用听赏《桔梗谣》和演唱歌曲《金达莱花开朵朵红》这两部分内容，教学设计的基本思路是：使学生通过多种形式听、唱“长白山下的歌谣”，深刻体验民族音乐“原生态”的美，以及其歌舞文化、思想内涵；在师生平等互动的学习氛围里，通过实践创作、对歌曲的再表现等形式，激发学生热爱民族音乐、热爱我们伟大祖国的情感。 堂教学中我以“新程”为指导思想，对教学设计进行了一些新的尝试。以下结合自己教学实践中的堂教学个案，和大家共同评析与探讨。 （七）教学过程 ᠄ 导入新过程：即“看风景”。 、AI播放《大长今》影片，背景音乐:《大长今》的主题曲《希望》。 （学生起立，跟随老师自由律动。） 师：刚才同学们听到的旋律出自？
第12页 0903060136 梁潇 0903060137 黄浩 0901014108 黄瑞尧 5.3性能分析 通信开销：在和平时期，验证和密钥协商协议的要求只有三路之间的网状路由器和网络用户和双向沟通网络用户之间。这是最低的通信回合要实现相互认证，因此，和平招致降低认证延迟。此外，通过设计，和平带来最低的额外因为它们可能对网络用户的通信开销如掌上电脑和智能手机进行的移动客户端比其他笔记本电脑访问无线网状网。这些移动客户端要少得多强大相比，网状路由器考虑到他们的沟通能力。在消息（M.1），（M.1），（M.2），网络用户只需要发送一组签名履行认证功能。作为我们立足本集团上签字的变化计划[8]中提出，签名的包括两个G的元素五个元素的Z带够。当使用[19]中描述的曲线，可以首要采取p到170位并使用G组1，其中每个元素是171位。因此，总群签名的长度为1192位或149字节。有了这些参数，安全性是大致相同作为一个标准的1024位RSA签名，这是128个字节[8]。也就是说，群签名的长度几乎是作为一个标准的RSA-1024的签名相同。 计算开销：在和平，最昂贵的计算操作的签名生成和验证。签名生成需要两个同构的应用中。同构计算，需要大约同时，作为一个在G1幂（使用快速计算的轨迹图）[8]。因此，签名生成需要约八幂（或multiexponentiations）和两个双线性映射计算。验证签名需要六个幂和3+2|网址|双线性映射计算。按照设计，和平采用会话认证的不对称对称的混合方法，降低计算成本。网络实体（Mesh 路由器和网络用户）执行昂贵的组签名操作相互验证，只有当建立一个新的会话，所有同一会话的后续数据交换是通过高效的基于MAC的方法进行验证。 更具体地说，和平需要进行相互认证，为建立一个新的会话时，执行一个签名生成和签名验证的网络用户。由此可以看出，签名验证的实际成本计算取决于一致资源定址器的大小，而签名的发电成本是固定的。和平可以主动控制的一致资源定址器的大小。此外，可以采取一种更为有效的吊销检查算法，其运行的时间是一致资源定址器的独立[8]中描述了对用户的隐私有点牺牲。这种技术可以进一步带来的总成本六幂和5个双线性映射计算的签名验证。另一方面，和平需要一个网状路由器进行相互认证其覆盖范围内的每个网络用户每每灯塔消息不同的会议和标志定期播出。 存储开销：在和平中，网络用户可以携带资源约束的普及设备，如掌上电脑和智能手机访问的无线网状网。因此，存储每个网络用户的开销应该是负担得起的现代普及设备。在我们的计划显示说明，在和平中的每个网络用户需要存储两个信息：他的小组的私钥及相关系统参数。该组的私钥为每个用户包含1组元素的G1和2个Z元素。如果我们首要选择p到170位，并使用G组1每个组171位的元素，每个组私钥用户只需消耗511位的内存，这是微不足道的现代普及设备。大多数的内存消耗部分是系统参数，其中可能包括代码来形容双线性组（G
Era of Big Data is a woman's age; women in the gene can accumulate and deal with big data/ women are born to accumulate and deal with big data. Many men and children, in fact, have been wondering about this special ability of women. Like, as a child, just as soon as you entered the house your Mother said immediately in a suspicious tone: “Liu zhijun, you didn’t do well in the exam today, did you.” Another example, you just have a glance at the mobile phone, your wife laughs: “Does Er gou the next door ask you to play games?” One more ex ample, when you close the door and make a phone call, your girlfriend will cry: “Who are shot in bed?” They are sometimes right, sometimes wrong. However, On the whole, the accuracy rate is higher than chance level. When they are wrong, men would sneer women always give way to foolish fancies; when they are right, men would say women are sensitive animal maybe with more acute sensory organs. Anyway, that is a guess. It has already scared man that overall accuracy rate is higher than the random level. In order to adapt to this point, the male also developed a very strong skills against reconnaissance. This part is beyond the scope of this article, so no more details about it. Some studies, such as Hanna Holmes’s paper, have indi cated that the white matter of the female’s brain is higher than that of the male. So they have very strong imagination of connecting things together. Some recent studies have shown that women are better than men in the "date" memory. That is the reason why they are able to remember all the birthdays, anniversaries, and even some of the great day of unimportant friends. No matter whether these results are true or not, I am afraid that this is not women's most outstanding ability. Women's most remarkable ability is a long-term tracking of some seemingly unimportant data to form their own baseline and pattern. Once the patterns of these data points are significantly different from the baseline she is familiar with, she knows something unusual. In their daily life, women do not consider the difference between causality and correlation. They believe in the principle: "There must be something wrong out of something unusual." People who talk about big data often take Lin Biao as an example. Lin Biao recorded some detailed and unimportant data after a battle. Such as seized guns, the proportion of rifles and pistols, the age levels of war prisoners, seized grain, whether they are sorghum or millet, etc., all of which were unavoidably recorded in the book. Others laughed at him. But later, he determined where the enemy headquarters were according to these data. What women do is almost the same. A girl A has a secret crush on boy B, but she usually doesn’t contact him directly. Two days later, I asked her if she wanted to ask him to have dinner together. She said he was playing. I wondered “how do you know that?” She said that boy B usually is on the line Gmail at 8:00 am, away status at8:30am, for he goes out to buy coffee and breakfast, on line again at 9:00am, busy status, for he is at work, away again at12:30am for lunch, on line for whole evenings, maybe for reading or playing games. His buddy C is on line at10:00 am, still online till 2:00am next day. He is a boy who gets up late and stays up late. His buddy D is on line for the most of the day. However, the most important pattern is that there are 2-3 days per week, during which they would be offline or away for 3-4 hours together. Conclusion: they are playing together.
大学毕业晚会主持词四人 四个主持人主持的大学毕业晚会应该怎么说主持词呢下面小编跟大家分享几篇大学毕业晚会主持词，以供参考! 大学毕业晚会主持词一 1.节奏引领时尚，余音环绕广场，新鲜的韵律，高难度的声响，一样为您缔造不一样的完美想象，下面请欣赏来自07音乐班的xxx为您带来的《》相信会给您带来意外的惊喜。 2.铃声清脆鼓铿锵，天山铃舞尽展情，来自天山的自然是蝶飞花影动，美丽各不同，那就让我们停下脚步，一饱眼福，欣赏由xxx为我们带来的舞蹈《天山铃舞》 3. 军中有歌，歌才动情，军旅里飞来一只熟悉的百灵，不错下面就由请xxx为大家献上一首耳熟能详的老歌，《军中飞来一只百灵》 4.炫酷才叫时尚，八零后心之向往，相信大家都一样，需要个性张扬。今天我们特意请来了城市建设学院的武状元优秀团队，为大家献上一段充满活力的XXX，感谢他们的到来，大家掌声欢迎! 5.相信大家都看过一部曾经风靡一时的电影，那是周杰伦曾经推出的一部年度巨献《不能说的秘密》.里面的四手联弹一定给大家留下了不可磨灭的深刻印象，旋律依旧在脑中回响。不过经典一样可以复制，精彩一样能够粘贴，下面给大家带来的这个惊喜，可谓是非常具有特色，一样是所见
不多，机会难得。下面请欣赏xxxx为大家带来的，钢琴四手连弹《军队进行曲》 6.幽幽云水意.漫漫古典情. 诗情画境的晕染为我们带来流动的娴静。请大家随着动人的舞蹈穿越书法的妙境，伴随优雅的琴韵体会超越喧嚣的古韵墨香。下面请欣赏xxx为您带来的xxxx 7.四年的岁月流光见证了你我在辽东学院的欢欣成长，相信由很多即将走出校园的同学都想倾诉衷肠，下面我们就请出来自05对外汉语的毕业生代表xxx听听她如何表达。 8.当你离开的时候，我送走你的只有沉默。当你离开我的时候，我绝不会把泪滴落。这是金达莱花的歌词大意，相信朝鲜族金达莱花的舞姿会像歌词一样优美，让人回味。下面请欣赏xxxx金达莱花。 9.是谁带来远古的呼唤，是谁留下千年的期盼，这首歌自打年初就开始被人重新无数次的翻唱，不过下面的歌曲，同样青藏高原的演唱，绝对会给您用实力带来不一样。由请xxxx 10.因为有爱，我们才牵手，因为有爱，我们才会风雨同舟。与身边爱自己的人共同牵手，一同遨游，幸福生活才能没有尽头。下面欣赏牵手。 11. 我对你的敬仰之情,如滔滔江水,连绵不绝;又如黄河之水,一发不可收拾;相信大家对电影《月光宝盒》中这一
对翻译的科学性和艺术性的思考 关键词: 翻译;科学性;艺术性 摘要: 翻译是科学还是艺术历来是译学家们争论的焦点。西方译学家奈达博士在60 年代曾有过建立翻译科学的设想,试图用语言学的理论和方法来说明翻译问题,但未能取得成功。而后,到了90 年代他则断言:翻译不是科学,而是艺术。笔者就奈达博士由科学论向艺术论的转变,对翻译的性质进行了理性思考:翻译中对“忠实”目标的追求体现了翻译的科学精神,而为实现“忠实”又离不开艺术创造,因此科学性和艺术性贯穿于翻译活动的全过程,二者互为补充,缺一不可。 Philosophic Thinking of the Science and the Art of Translating ———on Nida’s“Toward a Science of Translating” ZHANG Rui - qing1 ,ZHANG Hui - qing2 (1. The School of Foreigh L anguages , S hanxi University , Taiyuan , China ; 2. English Department , Northern China Engineering Institute , Taiyuan , China) Key words : t ranslation ;science ;art ;faithfulness. Abstract : What is t ranslating ? Is it science or art ? This has long been one of the focal cont roversies among t ranslatologist s. Dr. Eugene A. Nida attempted to establish a science of t ranslating by applying linguistic theories and approaches to t ranslating problems in the 1960s ,but failed. In the 1990s he claimed conversely that t ranslating was not science ,but skills. His shift prompt s the author of this essay to draw the couclusion that ,in the process of t ranslating ,the pursuit of faithfulness to the original reveals the scientific approach of t ranslators ,but to attain faithfulness , artistic creation plays an immeasurable role in good t ranslations. “翻译科学”是一门“研究翻译的科学”。怎样才能构成科学? 首先必须要有客观规律正如金堤先生所说:“艺术与科学之争的焦点是一个实质性的问题。翻译这一活动究竟是否受客观规律的支配? 如果受客观规律的支配,那么既然我们现在还没有完全认识这些规律,我们就必须用科学的方法加以研究,而如果这一活动主要靠独创,谈不到什么规律,那么我们只能把它当作一门艺术。”因此,翻译是科学还是艺术关键就在于其是否具有客观规律。我们在翻译活动中没有探索到客观规律之前,是无法断定翻译是科学的。西方译论家并没有主张建立“翻译科学” ,在他们的译论中,也不用“翻译科学”一词。在西方大学课程中,只有“翻译理论” ,或“翻译研究”,或“翻译学”。唯一用过“翻译科学”一词的,只有奈达博士。60年代,他在“Toward a Science of Translating”一书中指出,翻译是科学也是艺术,并试图用乔姆斯基的转换生成语法的原理,通过深层结构的分析,探索语际转换的客观规律,从而建立翻译科学。但这一尝试未能取得成功,语际转换的规律也未能找到。此后,他在1991 年发表的《翻译:可能与不可能》一文中说,我们不能使翻译成为一门科学,出色的翻译是创造性的艺术。可见奈达由科学派转向了艺术派,并从此放弃了建立翻译科学的设想。1998 年,他在答《外国语》记者问时,又重申了这一论点,认为翻译不可能成为科学。 一翻译科学论的困惑 寻求支配翻译活动的客观规律是历代译学家们孜孜以求的奋斗目标,困扰了几代译学家。只有到了现代,有了现代语言学的基础,才有可能打出翻译科学论的旗号,将侧重点放在科学的基点上。然而,，奈达为何一度认为翻译是科学也是艺术,而后来又说翻译不是科学只是艺术呢?翻译的科学论之所以陷入矛盾,其根源在于翻译对象所涉及的媒介———语言———本身所具有的特性———任意性特征。这种特性决定了科学无法完成其使命,因而即使很不情愿也不得不转而求助于艺术。首先,大多数人已经接受的一个事实是:虽然科学力图把文本语言中的意义一点一滴地落实,但语言却总是拒绝把它的全部意义交出来。事实上,现代批评
从翻译的时代到直译的时代 ) ) ) 基于贝尔曼视域之上的本雅明 华东师范大学袁筱一 提要: 自2 0 世纪80 年代翻译理论研究出现/ 文化转向0 以来, 本雅明的5译者的任务6几乎被所有翻译 理论研究者奉为/ 圣经0 。本雅明究竟在5译者的任务6 中如何触及翻译的本质问题的? 他又是基于怎样的/ 形 而上0 的语言观来谈论翻译的本质? 法国哲学家、翻译家安托万# 贝尔曼( An t oi n e Berman ) 所著的5 翻译的时 代6 对本雅明做出了完整、丰富同时又深入的解读。本文旨在依据5 翻译的时代6 所提供的理论视域, 指出本雅 明对传统翻译观的三个/ 颠覆0 , 并试图对5 译者的任务6 中所针对的翻译本质问题、可译性问题和直译问题有 所澄清。 关键词: 本雅明, 5 译者的任务6 , 贝尔曼, 5 翻译的时代6 , 翻译的本质 引言 在5沃尔特#本雅明或走向革命批评6中, 伊格 尔顿一开始就下了这样的判断: / 过去二十年的一 大显著标志乃是逐渐发现了沃尔特#本雅明, 其实 这并不令人惊诧。0( 伊格尔顿, 200 5: 3) 此话不错, 因为伊格尔顿的著作成书在198 1 年, 的确是解构 主义的大师和/ 后主0 们对本雅明顶礼膜拜的时 候。 兴于20 世纪50、60 年代的西方翻译理论研 究在经历了一段语言学途径的艰难历程之后, 也 在80 年代和哲学、文学批评一起发现了本雅明 ) ) ) 当然是因为本雅明那一篇自80 年代起几乎 就被奉为经典的5译者的任务6。我们在5译者的 任务6几乎可以找到翻译理论研究自80 年代起热 衷的所有语汇: 差异、欲求、碎片,作为本雅明译 波德莱尔5恶之花6的序言, 发表于1923 年的5译 者的任务6篇幅不长, 但晦涩难懂到让诸多大师们 无法放弃的程度: 这其中包括德里达、保罗# 德曼、 雅各布斯, 也包括为本文提供理解本雅明的理论 视域的安托万#贝尔曼( A nto i n e Be r man) 。 我们当然可以问, 在距离5译者的任务6初次 发表已经将近一个世纪的今天) ) ) 即便是距重新 / 发现0 本雅明也已经过去了将近半个世纪) ) ) 我 们还有什么必要再对5译者的任务6发生那么大的 兴趣? 甚至还要将它放在贝尔曼的视域中提出讨 论? 如果说中国的翻译理论研究在进入21 世纪 以后也毫不犹豫地以谈论/ 差异0 、/ 欲求0 、/ 碎片0 为乐趣, 我们可能) ) ) 鉴于本雅明在中国的研究
经典翻译段落（一） 科学对人体节奏有新发现 你有没有患过时差综合症，即由于长时间坐喷气飞机环球飞行跨越过很多时区而感到疲倦和沮丧?你有没有像北欧国家的很多人一样患过冬季忧郁症，即由于在阴郁的12月和1月老是看到冬日阴沉灰暗的天空而感到郁闷?也许一点点光就能解决你的问题——而且只需要照射你皮肤上一小块地方。实际上，美国科学家已竭尽全力进行研究——用光照射受试者的膝盖后部，试验光在提神方面的作用。 对付时差综合症和冬季忧郁症的东西可能是荷尔蒙褪黑激素。已知荷尔蒙褪黑激素能调节人体节奏。它于夜幕降临时分泌，可用于帮助治疗时差综合症和睡眠紊乱。冬天光线昏暗、白昼时间短，人们褪黑激素分泌较少，据说这就是许多人在天气昏暗时普遍有这种感觉(即冬季忧郁)的原因。 许多年来，专家们一直在试验用光治疗时差综合症和季节性情绪失调(“冬季忧郁证”)。他们建议患者坐在模仿太阳光自然波长的灯光前，以恢复褪黑激素。1996年，哈佛大学医学院的戴安娜·波文及其同事发现即使是昏暗的台灯也可以起到同样的作用。 动物和人接触光都会引起体内复杂的反应。纽约一个大学的研究小组说他们发现光照射在皮肤上会重新调整体内的生物钟。他们选择了胭窝做试验是因为那儿容易接触到而且远离眼睛，许多科学家认为那个部位决定着人体节奏的周期。 Scientists Shed New Light On The Body's Rhythms Have you ever suffered from jet-lag, the fatigue and depression that comes from long hours spent in a jet aircraft traveling across the world over many time zones? Or like many people in northern European countries, have you ever suffered the dark depression of winter blues, the feelings of gloom that comes from facing the somber December and January winter days under dark, cloudy skies? Maybe all you need is a little light -- and merely on a small patch of your skin. In fact, in experiments investigating the effect of light in raising our spirits, American scientists have done all their research using light played on the back of the subjects' knees. What could be a key to jet-lag and winter blues is the hormone melatonin, which is known to regulate body rhythms. It is secreted as night falls and it can be used to help to overcome jet-lag and some sleep disorders. The low level of melatonin we experience in winter when light is dull and daylight hours are shorter is said to be cause of that common feeling many people get in dull weather -- winter depression. For years experts have experimented with treating jet-lag and seasonal affective disorder ("winter depression") with light. They
精彩的大学毕业晚会主持词示范文格式本推荐 Ａ：青春是一曲荡气回肠的歌，三年前我们怀着彩色梦想走进了鄂大，三年中我们有过欢笑，流过泪水，经历磨炼，得到成长Ｂ：三年后的今天，我们在这里重温青春过往，因为明天就将各奔天涯。也正因为此，今夜，我们承载了太多的祝福与惦念，寄托了太多的关心与企盼。 Ｃ：今晚，让我们再一次重温，那些感动过我们的人和事：灯火通明的教学楼里用功的身影，篮球场上保卫集体尊严的男儿霸气，满是欢声笑语的宿舍边不着边际的闲谈…… Ｄ：又一个三年轮回之后，在同样微凉的夏夜，你是否会记起校园里的梧桐树，你是否会记起日记本里的书签，那些五彩缤纷的日子? Ａ：无数个三年之后，你们的思念是否会有增无减?在你成长的岁月里，在你闯荡社会的每一天，是否会有那么几个霎时让你渴望回到过去 Ｂ：让我们静静享受一下挑战，在日复一日与时间的赛跑中，你会变得更加坚强，更加神采奕奕!又一个青春之旅从今晚启航，又一个光阴的故事在今晚讲述 Ｃ：亲爱的同窗，不要带着离别的愁绪，因为明天又是一个新的起点，因为我们相信再次相逢，我们还是一首动人的歌!Ｄ：很快乐今天能有这个时机同大家相聚一堂，共叙离别。就让今天铭刻在我们心间，让母校留住我们的风采!
Ａ：今天，我们也非常荣幸的请到了…… Ｂ：下面让我们用热烈的掌声有请……上台讲话 结束语Ａ：愉快的舞蹈表达不尽我们对母校的敬意 Ｂ：热情的赞歌唱不尽我们对母校的一腔深情 Ｃ：流火的六月，我们将带着恩师的叮咛，怀着必胜的信心，走向新的征程 Ｄ：绚烂的七月，我们将载着母校的祝愿，带着亲人的希望，向着新的征程扬帆起航 Ａ：教师们，同学们，欢送10级毕业生联欢晚会合：到此结束Ａ李：毕业，是一个沉重的动词; 刘：毕业，是一个让人一生难忘的名词; 李：毕业，是感动时流泪的形容词; 刘：毕业，是当我们以后孤寂时候，带着浅笑和遗憾去回想时的副词; 李：毕业，是我们夜半梦醒，触碰不到而无限感伤的虚词。 刘：若干年后，假设我们还能够想起那段时光，也许这不属于难忘，也不属于永远，而仅仅是一段记录了成长经历的回忆。 李：尊敬的各位领导教师 刘：亲爱的各位同学们 合：大家晚上好! 李：很荣幸和大家相聚在这激情如火的六月，在这充满忧伤的六月!