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StandardmuseumpracticecanwashawayDNA. 1.Washing,brushingandvarnishingfossils—allstandardconservationtreatmentsusedbymanyfossilhuntersandmuseumcuratorsalike—vastlyreducesthechancesofrecoveringancientDNA. 2.Instead,excavatorsshouldbehandlingatleastsomeoftheirbountywithgloves,andfreezingsamplesastheyarefound,dirtandall,concludesapaperintheProceedingsoftheNationalAcademyofSciencestoday. 3.AlthoughmanypalaeontologistsknowanecdotallythatthisisthebestwaytouptheoddsofextractinggoodDNA,Eva-MariaGeigloftheJacquesMonodInstituteinParis,France,andhercolleagueshavenowshownjusthowimportantconservationpracticescanbe.Thisinformation,theysay,needstobehammeredhomeamongthepeoplewhoareactuallyoutinthefielddiggingupbones. 4.Geiglandhercolleagueslookedat3,200-year-oldfossilbonesbelongingtoasingleindividualofanextinctcattlespecies,calledanaurochs.ThefossilsweredugupatasiteinFranceattwodifferenttimes—eitherin1947,andstoredinamuseumcollection,orin2004,andconservedinsterileconditionsat-20oC. 5.Theteam'sattemptstoextractDNAfromthe1947bonesallfailed.Thenewlyexcavatedfossils,however,allyieldedDNA. 6.Becausetheboneshadbeenburiedforthesameamountoftime,andinthesameconditions,theconservationmethodhadtobetoblamesaysGeigl."AsmuchDNAwasdegradedinthese57yearsasinthe3,200yearsbefore,"shesays. Washin,washout 7.Becausemanypalaeontologistsbasetheirworkontheshapeoffossilsalone,theirmethodsofconservationarenotdesignedtopreserveDNA,Geiglexplains. 8.Thebiggestproblemishowtheyarecleaned.Fossilsareoftenwashedtogetheron-siteinalargebath,whichcanallowwater—andcontaminantsintheformofcontemporaryDNA—topermeateintotheporousbones."NotonlyistheauthenticDNAgettingwashedout,butcontaminationisgettingwashedin,"saysGeigl. 9.MostancientDNAspecialistsknowthisalready,saysHendrikPoinar,anevolutionarygeneticistatMcMasterUniversityinOntario,Canada.Butthatdoesn'tmeanthatbestpracticehasbecomewidespreadamongthosewhoactuallyfindthefossils. 10.GettingholdoffossilsthathavebeenpreservedwiththeirDNAinmindreliesoncloserelationshipsbetweenlab-basedgeneticistsandtheexcavators,sayspalaeogeneticistSvantePbooftheMaxPlanckInstituteforEvolutionaryAnthropologyinLeipzig,Germany.Andthatonlyoccursinexceptionalcases,hesays. 11.Pbo'steam,whichhasbeensequencingNeanderthalDNA,continuallyfacestheseproblems."WhenyouwanttostudyancienthumanandNeanderthalremains,there'sabigissueofcontaminationwithcontemporaryhumanDNA,"hesays. 12.Thisdoesn'tmeanthatallmuseumspecimensarefatallyflawed,notesPbo.TheNeanderthalfossilsthatwererecentlysequencedinhisownlab,forexample,hadbeenpartofamuseumcollectiontreatedinthetraditionalway.ButPboiskeentoseesamplesoffossilsfromeverymajorfindpreservedinlinewithGeigl'srecommendations—justincase. Warmandwet 13.Geiglherselfbelievesthat,withcooperationbetweenbenchandfieldresearchers,preservingfossilsproperlycouldopenupavenuesofdiscoverythathavelongbeenassumedclosed. 14.Muchhumanculturaldevelopmenttookplaceintemperateregions.DNAdoesnotsurvivewellinwarmenvironmentsinthefirstplace,andcanvanishwhenfossilsarewashedandtreated.Forthisreason,Geiglsays,mostancientDNAstudieshavebeendoneonpermafrostsamples,suchasthewoollymammoth,oronremainsshelteredfromtheelementsincoldcaves—includingcavebearandNeanderthalfossils. 15.Betterconservationmethods,andafocusonfreshfossils,couldboostDNAextractionfrommoredelicatespecimens,saysGeigl.Andthatcouldshedmorelightonthestoryofhumanevolution. (640wordsnature) Glossary Palaeontologists古生物学家 Aurochs欧洲野牛 Neanderthal(人类学)尼安德特人,旧石器时代的古人类。 Permafrost(地理)永冻层 Questions1-6 AnswerthefollowingquestionsbyusingNOMORETHANTHREEWORDSforeachanswer. 1.Howdidpeopletraditionallytreatfossils? 2.WhatsuggestionsdoGeiglandhercolleaguesgiveonwhatshouldbedonewhenfossilsarefound? 3.Whatproblemsmaybeposediffossilbonesarewashedon-site?NameONE. 4.WhatcharacteristicdofossilboneshavetomakethemsusceptibletobecontaminatedwithcontemporaryDNAwhentheyarewashed? 5.Whatcouldbebetterunderstoodwhenconservationtreatmentsareimproved? 6.Thepassagementionedseveralanimalspeciesstudiedbyresearchers.Howmanyofthemarementioned? Questions7-11 Dothefollowingstatementsagreewiththeinformationgiveninthepassage?PleasewriteTRUEifthestatementagreeswiththewriterFALSEifthestatementdoesnotagreewiththewriterNOTGIVENifthereisnoinformationaboutthisinthepassage. 7.IntheirpaperpublishedintheProceedingsoftheNationalAcademyofSciences,GeiglandhercolleagueshaveshownwhatconservationpracticesshouldbefollowedtopreserveancientDNA. 8.ThefossilbonesthatGeiglandhercolleaguesstudiedareallfromthesameaurochs. 9.Geneticistsdon'thavetoworkonsite. 10.OnlynewlyexcavatedfossilbonesusingnewconservationmethodssuggestedbyGeiglandhercolleaguescontainancientDNA. 11.Paaboisstillworriedaboutthepotentialproblemscausedbytreatmentsoffossilsintraditionalway. Questions12-13 CompletethefollowingthestatementsbychoosingletterA-Dforeachanswer. 12.“Thisinformation”inparagraph3indicates: [A]ItiscriticaltofollowproperpracticesinpreservingancientDNA. [B]ThebestwayofgettinggoodDNAistohandlefossilswithgloves. [C]Fossilhuntersshouldwearhome-madehammerswhilediggingupbones. [D]Manypalaeontologistsknowhowoneshoulddointreatingfossils. 13.ThestudyconductedbyGeiglandhercolleaguessuggests: [A]thefactthatancientDNAcannotberecoveredfromfossilbonesexcavatedinthepast. [B]thecorrelationbetweentheamountofburyingtimeandthatoftherecoveredDNA. [C]thepaceatwhichDNAdegrades. [D]thecorrelationbetweenconservationpracticesanddegradationofDNA.
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Don'twashthosefossils!

StandardmuseumpracticecanwashawayDNA.

1.Washing,brushingandvarnishingfossils—allstandardconservationtreatmentsusedbymanyfossilhuntersandmuseumcuratorsalike—vastlyreducesthechancesofrecoveringancientDNA.

2.Instead,excavatorsshouldbehandlingatleastsomeoftheirbountywithgloves,andfreezingsamplesastheyarefound,dirtandall,concludesapaperintheProceedingsoftheNationalAcademyofSciencestoday.

3.AlthoughmanypalaeontologistsknowanecdotallythatthisisthebestwaytouptheoddsofextractinggoodDNA,Eva-MariaGeigloftheJacquesMonodInstituteinParis,France,andhercolleagueshavenowshownjusthowimportantconservationpracticescanbe.Thisinformation,theysay,needstobehammeredhomeamongthepeoplewhoareactuallyoutinthefielddiggingupbones.

4.Geiglandhercolleagueslookedat3,200-year-oldfossilbonesbelongingtoasingleindividualofanextinctcattlespecies,calledanaurochs.ThefossilsweredugupatasiteinFranceattwodifferenttimes—eitherin1947,andstoredinamuseumcollection,orin2004,andconservedinsterileconditionsat-20oC.

5.Theteam'sattemptstoextractDNAfromthe1947bonesallfailed.Thenewlyexcavatedfossils,however,allyieldedDNA.

6.Becausetheboneshadbeenburiedforthesameamountoftime,andinthesameconditions,theconservationmethodhadtobetoblamesaysGeigl."AsmuchDNAwasdegradedinthese57yearsasinthe3,200yearsbefore,"shesays.

Washin,washout

7.Becausemanypalaeontologistsbasetheirworkontheshapeoffossilsalone,theirmethodsofconservationarenotdesignedtopreserveDNA,Geiglexplains.

8.Thebiggestproblemishowtheyarecleaned.Fossilsareoftenwashedtogetheron-siteinalargebath,whichcanallowwater—andcontaminantsintheformofcontemporaryDNA—topermeateintotheporousbones."NotonlyistheauthenticDNAgettingwashedout,butcontaminationisgettingwashedin,"saysGeigl.

9.MostancientDNAspecialistsknowthisalready,saysHendrikPoinar,anevolutionarygeneticistatMcMasterUniversityinOntario,Canada.Butthatdoesn'tmeanthatbestpracticehasbecomewidespreadamongthosewhoactuallyfindthefossils.

10.GettingholdoffossilsthathavebeenpreservedwiththeirDNAinmindreliesoncloserelationshipsbetweenlab-basedgeneticistsandtheexcavators,sayspalaeogeneticistSvantePbooftheMaxPlanckInstituteforEvolutionaryAnthropologyinLeipzig,Germany.Andthatonlyoccursinexceptionalcases,hesays.

11.Pbo'steam,whichhasbeensequencingNeanderthalDNA,continuallyfacestheseproblems."WhenyouwanttostudyancienthumanandNeanderthalremains,there'sabigissueofcontaminationwithcontemporaryhumanDNA,"hesays.

12.Thisdoesn'tmeanthatallmuseumspecimensarefatallyflawed,notesPbo.TheNeanderthalfossilsthatwererecentlysequencedinhisownlab,forexample,hadbeenpartofamuseumcollectiontreatedinthetraditionalway.ButPboiskeentoseesamplesoffossilsfromeverymajorfindpreservedinlinewithGeigl'srecommendations—justincase.

Warmandwet

13.Geiglherselfbelievesthat,withcooperationbetweenbenchandfieldresearchers,preservingfossilsproperlycouldopenupavenuesofdiscoverythathavelongbeenassumedclosed.

14.Muchhumanculturaldevelopmenttookplaceintemperateregions.DNAdoesnotsurvivewellinwarmenvironmentsinthefirstplace,andcanvanishwhenfossilsarewashedandtreated.Forthisreason,Geiglsays,mostancientDNAstudieshavebeendoneonpermafrostsamples,suchasthewoollymammoth,oronremainsshelteredfromtheelementsincoldcaves—includingcavebearandNeanderthalfossils.

15.Betterconservationmethods,andafocusonfreshfossils,couldboostDNAextractionfrommoredelicatespecimens,saysGeigl.Andthatcouldshedmorelightonthestoryofhumanevolution.

(640wordsnature)

Glossary

Palaeontologists古生物学家

Aurochs欧洲野牛

Neanderthal(人类学)尼安德特人,旧石器时代的古人类。

Permafrost(地理)永冻层

Questions1-6

AnswerthefollowingquestionsbyusingNOMORETHANTHREEWORDSforeachanswer.

1.Howdidpeopletraditionallytreatfossils?

2.WhatsuggestionsdoGeiglandhercolleaguesgiveonwhatshouldbedonewhenfossilsarefound?

3.Whatproblemsmaybeposediffossilbonesarewashedon-site?NameONE.

4.WhatcharacteristicdofossilboneshavetomakethemsusceptibletobecontaminatedwithcontemporaryDNAwhentheyarewashed?

5.Whatcouldbebetterunderstoodwhenconservationtreatmentsareimproved?

6.Thepassagementionedseveralanimalspeciesstudiedbyresearchers.Howmanyofthemarementioned?

Questions7-11

Dothefollowingstatementsagreewiththeinformationgiveninthepassage?PleasewriteTRUEifthestatementagreeswiththewriterFALSEifthestatementdoesnotagreewiththewriterNOTGIVENifthereisnoinformationaboutthisinthepassage.

7.IntheirpaperpublishedintheProceedingsoftheNationalAcademyofSciences,GeiglandhercolleagueshaveshownwhatconservationpracticesshouldbefollowedtopreserveancientDNA.

8.ThefossilbonesthatGeiglandhercolleaguesstudiedareallfromthesameaurochs.

9.Geneticistsdon'thavetoworkonsite.

10.OnlynewlyexcavatedfossilbonesusingnewconservationmethodssuggestedbyGeiglandhercolleaguescontainancientDNA.

11.Paaboisstillworriedaboutthepotentialproblemscausedbytreatmentsoffossilsintraditionalway.

Questions12-13

CompletethefollowingthestatementsbychoosingletterA-Dforeachanswer.

12.“Thisinformation”inparagraph3indicates:

[A]ItiscriticaltofollowproperpracticesinpreservingancientDNA.

[B]ThebestwayofgettinggoodDNAistohandlefossilswithgloves.

[C]Fossilhuntersshouldwearhome-madehammerswhilediggingupbones.

[D]Manypalaeontologistsknowhowoneshoulddointreatingfossils.

13.ThestudyconductedbyGeiglandhercolleaguessuggests:

[A]thefactthatancientDNAcannotberecoveredfromfossilbonesexcavatedinthepast.

[B]thecorrelationbetweentheamountofburyingtimeandthatoftherecoveredDNA.

[C]thepaceatwhichDNAdegrades.

[D]thecorrelationbetweenconservationpracticesanddegradationofDNA.

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正确答案:

1.washing, brushing, varnishing 见第一段。

2.handling with gloves / freezing samples ( any one of the two ) 见第二段。

3.losing authentic DNA / being contaminated / contamination ( any one of the three) 见第八段“Not only is the authentic DNA getting washed out, but contamination is getting washed in”(答being contaminated或 contamination比较保险)

4.they are porous porous 的意思是多孔的。见第八段“...which can allow water — and contaminants in the form of contemporary DNA — to permeate into the porous bones.”

5.human evolution 见第十五段。其中“shed light on sth”的意思是使某事显得非常清楚,使人了解某事。

6.4 分别为第四段的“an extinct cattle species, called an aurochs”,即欧洲野牛,已经绝迹;第十一段“Neanderthal”, 是人类学用语,尼安德特人,旧石器时代的古人类;第十四段“woolly mammoth”和“cave bear”,其中mammoth是猛犸,一种古哺乳动物。

7.T 见第二段。

8.T 见第四段“Geigl and her colleagues looked at 3,200-year-old fossil bones belonging to a single individual of an extinct cattle species, called an aurochs.”即他们研究的骨化石是一头欧洲野牛身上的。

9.NG

10.F 见第十二段第一、二句话。

11.T 见第十二段末句“But P bo is keen to see samples of fossils from every major find preserved in line with Geigl's recommendations — just in case.”意即为保险起见,Paabo还是非常希望见到用Geigl建议的方法保存的化石样本。“just in case” 的意思是以防万一,就是Paabo对用传统保存处理的化石不放心的意思。

12.A 见第三段。This information就是前一句中“...just how important conservation practices can be”(to preserve good DNA)。“be hammered”之中hammer一词的意思是不断重复强调。

13.D 面信息。需要理解文章各处关于Geigl和她的同事所作的研究。

答案解析:

暂无解析

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How a Frenchman is reviving McDonald’s in Europe

A. When Denis Hennequin took over as the European boss of McDonald’s in January 2004, the world’s biggest restaurant chain was showing signs of recovery in America and Australia, but sales in Europe were sluggish or declining. One exception was France, where Mr Hennequin had done a sterling job as head of the group’s French subsidiary to sell more Big Macs to his compatriots. His task was to replicate this success in all 41 of the European countries where anti-globalisers’ favourite enemy operates.

B. So far Mr Hennequin is doing well. Last year European sales increased by 5.8% and the number of customers by 3.4%, the best annual results in nearly 15 years. Europe accounted for 36% of the group’s profits and for 28% of its sales. December was an especially good month as customers took to seasonal menu offerings in France and Britain, and to a promotion in Germany based on the game of Monopoly.

C. Mr Hennequin’s recipe for revival is to be more open about his company’s operations, to be “locally relevant”, and to improve the experience of visiting his 6,400 restaurants. McDonald’s is blamed for making people fat, exploiting workers, treating animals cruelly, polluting the environment and simply for being American. Mr Hennequin says he wants to engage in a dialogue with the public to address these concerns.

D. He introduced “open door” visitor days in each country which became hugely popular. In Poland alone some 50,000 visitors came to McDonald’s through the visitors’ programme last year. The Nutrition Information Initiative, launched last year, put detailed labels on McDonald’s packaging with data on calories, protein, fat, carbohydrates and salt content. The details are also printed on tray-liners.

E. Mr Hennequin also wants people to know that “McJobs”, the low-paid menial jobs at McDonald’s restaurants, are much better than people think. But some of his efforts have backfired: last year he sparked a controversy with the introduction of a “McPassport” that allows McDonald’s employees to work anywhere in the European Union. Politicians accused the firm of a ploy to make cheap labour from eastern Europe more easily available to McDonald’s managers across the continent.

F. To stay in touch with local needs and preferences, McDonald’s employs local bosses as much as possible. A Russian is running McDonald’s in Russia, though a Serb is in charge of Germany. The group buys mainly from local suppliers. Four-fifths of its supplies in France come from local farmers, for example. (Some of the French farmers who campaigned against the company in the late 1990s subsequently discovered that it was, in fact, buying their produce.) And it hires celebrities such as Heidi Klum, a German model, as local brand ambassadors.

G. In his previous job Mr Hennequin established a “design studio” in France to spruce up his company’s drab restaurants and adapt the interior to local tastes. The studio is now masterminding improvements everywhere in Europe. He also set up a “food studio”, where cooks devise new recipes in response to local trends.

H. Given France’s reputation as the most anti-American country in Europe, it seems odd that McDonald’s revival in Europe is being led by a Frenchman, using ideas cooked up in the French market. But France is in fact the company’s most profitable market after America. The market where McDonald’s is weakest in Europe is not France, but Britain.

I. “Fixing Britain should be his priority,” says David Palmer, a restaurant analyst at UBS. Almost two-thirds of the 1,214 McDonald’s restaurants in Britain are company-owned, compared with 40% in Europe and 15% in America. The company suffers from the volatility of sales at its own restaurants, but can rely on steady income from franchisees. So it should sell as many underperforming outlets as possible, says Mr Palmer.

J. M.Mark Wiltamuth, an analyst at Morgan Stanley, estimates that European company-owned restaurants’ margins will increase slightly to 16.4% in 2007. This is still less than in the late 1990s and below America’s 18-19% today. But it is much better than before Mr Hennequin’s reign. He is already being tipped as the first European candidate for the group’s top job in Illinois. Nobody would call that a McJob.

Notes to Reading Passage 1

1.sterling高质量的

e.g. He has many sterling qualities. 他身上有许多优秀的品质。

2. menial 不体面的, 乏味的(工作、职业)

3. spruce up打扮整齐、漂亮、装饰

4. mastermind指挥、谋划(一个计划或活动)

e.g. The police know who masterminded the robbery.警察知道是谁策划了那次抢劫。

5. underperform表现不佳表现出低于标准的工作水平、企业出现亏本

Questions 1-6

Do the following statements reflect the claims of the writer in Reading Passage 1?

Write your answer in Boxes 1-6 on your answer sheet.

TRUE if the statement reflects the claims of the writer

FALSE if the statement contradicts the claims of the writer

NOT GIVEN if it is impossible to say what the writer thinks about this

1. McDonald was showing the sign of recovery in all European countries except France after Denis Hennequin took office as the boss of Euro-markets.

2. Starting from last year, detailed labels are put on McDonald’s packaging and detailed information is also printed on tray-liners.

3. France is said to be the most anti-American country in Europe, but the ideas of the “open door” visiting days and “McPassport” are invented in the French market.

4. Britain possesses the weakest McDonald market among European countries and approximately 1214 McDonald’s restaurants are company-owned.

5. According to David Palmer, a restaurant analyst at UBS, David Hennequin should treat the problem about McDonald in Britain as the most important thing.

6. David Palmer suggested that the management of McDonalod in Italy should sell as many its outlets which lose money in business as possible for revival.

Questions 7-10

Choose the appropriate letters A-D and write them in boxes 7-10 on your answe sheet.

7. The word “sterling” in line 3 of Paragraph A means__________.

A. difficult

B. menial

C. terrible

D. excellent

8. Which of the following statements on the accusation of MacDonald is NOT TRUE?

A. It tends to make people fat.

B. Its operations are very vague.

C. It tends to exploit workers.

D. It tends to treat animals cruelly.

9. Which of the following measures taken by Denis Hennequin produced undesired result?

A. “Food Studio” scheme.

B. “Open Door” visitor days.

C. The “McPassport” scheme.

D. The Nutrition Information Initiative.

10. What did Denis Hennequin do so as to respond to local trends?

A. set up a “Food Studio” .

B. established a “Design Studio”.

C. hired celebrities as local brand ambassadors.

D. employed local bosses as much as possible.

Questions 11-14

Complete each of the following statements (Questions 11-14) with words or number taken from Reading Passage 1.

Write NO MORE THAN THREE WORDS for each answer.

Write your answers in boxes 11-14 on your answer sheet.

11. After January 2004, McDonald was making improvement following a period of slump in America and Australia, but sales in Europe were ………………………….

12. Business of McDonald in France and Britain was particularly good in December since customers took to ……………………………..

13. Compared with other countries, France is McDonald’s ………………………. next to America.

14. ……………………. of McDonald’s restaurants in America are companied–owned and the figure is much lower than that in Britain.

1There'sadimmerswitchinsidethesunthatcausesitsbrightnesstoriseandfallontimescalesofaround100,000years-exactlythesameperiodasbetweeniceagesonEarth.Sosaysaphysicistwhohascreatedacomputermodelofourstar'score.

2RobertEhrlichofGeorgeMasonUniversityinFairfax,Virginia,modelledtheeffectoftemperaturefluctuationsinthesun'sinterior.Accordingtothestandardview,thetemperatureofthesun'scoreisheldconstantbytheopposingpressuresofgravityandnuclearfusion.However,Ehrlichbelievedthatslightvariationsshouldbepossible.

3HetookashisstartingpointtheworkofAttilaGrandpierreoftheKonkolyObservatoryoftheHungarianAcademyofSciences.In2005,Grandpierreandacollaborator,Gáborágoston,calculatedthatmagneticfieldsinthesun'scorecouldproducesmallinstabilitiesinthesolarplasma.Theseinstabilitieswouldinducelocalisedoscillationsintemperature.

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5ThesetwotimescalesareinstantlyrecognisabletoanyonefamiliarwithEarth'siceages:forthepastmillionyears,iceageshaveoccurredroughlyevery100,000years.Beforethat,theyoccurredroughlyevery41,000years.

6MostscientistsbelievethattheiceagesaretheresultofsubtlechangesinEarth'sorbit,knownastheMilankovitchcycles.OnesuchcycledescribesthewayEarth'sorbitgraduallychangesshapefromacircletoaslightellipseandbackagainroughlyevery100,000years.ThetheorysaysthisalterstheamountofsolarradiationthatEarthreceives,triggeringtheiceages.However,apersistentproblemwiththistheoryhasbeenitsinabilitytoexplainwhytheiceageschangedfrequencyamillionyearsago.

7"InMilankovitch,thereiscertainlynogoodideawhythefrequencyshouldchangefromonetoanother,"saysNeilEdwards,aclimatologistattheOpenUniversityinMiltonKeynes,UK.NoristhetransitionproblemtheonlyonetheMilankovitchtheoryfaces.EhrlichandothercriticsclaimthatthetemperaturevariationscausedbyMilankovitchcyclesaresimplynotbigenoughtodriveiceages.

8However,EdwardsbelievesthesmallchangesinsolarheatingproducedbyMilankovitchcyclesarethenamplifiedbyfeedbackmechanismsonEarth.Forexample,ifseaicebeginstoformbecauseofaslightcooling,carbondioxidethatwouldotherwisehavefounditswayintotheatmosphereaspartofthecarboncycleislockedintotheice.ThatweakensthegreenhouseeffectandEarthgrowsevencolder.

9AccordingtoEdwards,thereisnolackofsuchmechanisms."Ifyouaddtheireffectstogether,thereismorethanenoughfeedbacktomakeMilankovitchwork,"hesays."Theproblemnowisidentifyingwhichmechanismsareatwork."ThisiswhyscientistslikeEdwardsarenotyetreadytogiveuponthecurrenttheory."Milankovitchcyclesgiveusiceagesroughlywhenweobservethemtohappen.Wecancalculatewhereweareinthecycleandcompareitwithobservation,"hesays."Ican'tseeanywayoftesting[Ehrlich's]ideatoseewhereweareinthetemperatureoscillation."

10Ehrlichconcedesthis."Ifthereisawaytotestthistheoryonthesun,Ican'tthinkofonethatispractical,"hesays.That'sbecausevariationover41,000to100,000yearsistoogradualtobeobserved.However,theremaybeawaytotestitinotherstars:reddwarfs.Theircoresaremuchsmallerthanthatofthesun,andsoEhrlichbelievesthattheoscillationperiodscouldbeshortenoughtobeobserved.Hehasyettocalculatethepreciseperiodortheextentofvariationinbrightnesstobeexpected.

11NigelWeiss,asolarphysicistattheUniversityofCambridge,isfarfromconvinced.HedescribesEhrlich'sclaimsas"utterlyimplausible".EhrlichcountersthatWeiss'sopinionisbasedonthestandardsolarmodel,whichfailstotakeintoaccountthemagneticinstabilitiesthatcausethetemperaturefluctuations.

Questions1-4

CompleteeachofthefollowingstatementswithOneorTwonamesofthescientistsfromtheboxbelow.

WritetheappropriatelettersA-Einboxes1-4onyouranswersheet.

A.AttilaGrandpierre

B.Gáborágoston

C.NeilEdwards

D.NigelWeiss

E.RobertEhrlich

1....claimsthereadimmerswitchinsidethesunthatcausesitsbrightnesstoriseandfallinperiodsaslongasthosebetweeniceagesonEarth.

2....calculatedthattheinternalsolarmagneticfieldscouldproduceinstabilitiesinthesolarplasma.

3....holdsthatMilankovitchcyclescaninducechangesinsolarheatingonEarthandthechangesareamplifiedonEarth.

4....doesn'tbelieveinEhrlich'sviewpointsatall.

Questions5-9

Dothefollowingstatementsagreewiththeinformationgiveninthereadingpassage?

Inboxes5-9onyouranswersheetwrite

TRUEifthestatementistrueaccordingtothepassage

FALSEifthestatementisfalseaccordingtothepassage

NOTGIVENiftheinformationisnotgiveninthepassage

5.Theiceageschangedfrequencyfrom100,000to41,000yearsamillionyearsago.

6.ThesoleproblemthattheMilankovitchtheorycannotsolveistoexplainwhytheiceagefrequencyshouldshiftfromonetoanother.

7.Carbondioxidecanbelockedartificiallyintoseaicetoeliminatethegreenhouseeffect.

8.SomescientistsarenotreadytogiveuptheMilankovitchtheorythoughtheyhaven'tfiguredoutwhichmechanismsamplifythechangesinsolarheating.

9.BothEdwardsandEhrlichbelievethatthereisnopracticalwaytotestwhenthesolartemperatureoscillationbeginsandwhenends.

Questions10-14

Completethenotesbelow.

ChooseonesuitablewordfromtheReadingPassageaboveforeachanswer.

Writeyouranswersinboxes10-14onyouranswersheet.

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2 Robert Ehrlich of George Mason University in Fairfax, Virginia, modelled the effect of temperature fluctuations in the sun's interior. According to the standard view, the temperature of the sun's core is held constant by the opposing pressures of gravity and nuclear fusion. However, Ehrlich believed that slight variations should be possible.

3 He took as his starting point the work of Attila Grandpierre of the Konkoly Observatory of the Hungarian Academy of Sciences. In 2005, Grandpierre and a collaborator, Gábor ágoston, calculated that magnetic fields in the sun's core could produce small instabilities in the solar plasma. These instabilities would induce localised oscillations in temperature.

4 Ehrlich's model shows that whilst most of these oscillations cancel each other out, some reinforce one another and become long-lived temperature variations. The favoured frequencies allow the sun's core temperature to oscillate around its average temperature of 13.6 million kelvin in cycles lasting either 100,000 or 41,000 years. Ehrlich says that random interactions within the sun's magnetic field could flip the fluctuations from one cycle length to the other.

5 These two timescales are instantly recognisable to anyone familiar with Earth's ice ages: for the past million years, ice ages have occurred roughly every 100,000 years. Before that, they occurred roughly every 41,000 years.

6 Most scientists believe that the ice ages are the result of subtle changes in Earth's orbit, known as the Milankovitch cycles. One such cycle describes the way Earth's orbit gradually changes shape from a circle to a slight ellipse and back again roughly every 100,000 years. The theory says this alters the amount of solar radiation that Earth receives, triggering the ice ages. However, a persistent problem with this theory has been its inability to explain why the ice ages changed frequency a million years ago.

7 "In Milankovitch, there is certainly no good idea why the frequency should change from one to another," says Neil Edwards, a climatologist at the Open University in Milton Keynes, UK. Nor is the transition problem the only one the Milankovitch theory faces. Ehrlich and other critics claim that the temperature variations caused by Milankovitch cycles are simply not big enough to drive ice ages.

8 However, Edwards believes the small changes in solar heating produced by Milankovitch cycles are then amplified by feedback mechanisms on Earth. For example, if sea ice begins to form because of a slight cooling, carbon dioxide that would otherwise have found its way into the atmosphere as part of the carbon cycle is locked into the ice. That weakens the greenhouse effect and Earth grows even colder.

9 According to Edwards, there is no lack of such mechanisms. "If you add their effects together, there is more than enough feedback to make Milankovitch work," he says. "The problem now is identifying which mechanisms are at work." This is why scientists like Edwards are not yet ready to give up on the current theory. "Milankovitch cycles give us ice ages roughly when we observe them to happen. We can calculate where we are in the cycle and compare it with observation," he says. "I can't see any way of testing [Ehrlich's] idea to see where we are in the temperature oscillation."

10 Ehrlich concedes this. "If there is a way to test this theory on the sun, I can't think of one that is practical," he says. That's because variation over 41,000 to 100,000 years is too gradual to be observed. However, there may be a way to test it in other stars: red dwarfs. Their cores are much smaller than that of the sun, and so Ehrlich believes that the oscillation periods could be short enough to be observed. He has yet to calculate the precise period or the extent of variation in brightness to be expected.

11 Nigel Weiss, a solar physicist at the University of Cambridge, is far from convinced. He describes Ehrlich's claims as "utterly implausible". Ehrlich counters that Weiss's opinion is based on the standard solar model, which fails to take into account the magnetic instabilities that cause the temperature fluctuations.

Questions 1-4

Complete each of the following statements with One or Two names of the scientists from the box below.

Write the appropriate letters A-E in boxes 1-4 on your answer sheet.

A. Attila Grandpierre

B. Gábor ágoston

C. Neil Edwards

D. Nigel Weiss

E. Robert Ehrlich

1. ...claims there a dimmer switch inside the sun that causes its brightness to rise and fall in periods as long as those between ice ages on Earth.

2. ...calculated that the internal solar magnetic fields could produce instabilities in the solar plasma.

3. ...holds that Milankovitch cycles can induce changes in solar heating on Earth and the changes are amplified on Earth.

4. ...doesn't believe in Ehrlich's viewpoints at all.

Questions 5-9

Do the following statements agree with the information given in the reading passage?

In boxes 5-9 on your answer sheet write

TRUE if the statement is true according to the passage

FALSE if the statement is false according to the passage

NOT GIVEN if the information is not given in the passage

5. The ice ages changed frequency from 100,000 to 41,000 years a million years ago.

6. The sole problem that the Milankovitch theory can not solve is to explain why the ice age frequency should shift from one to another.

7. Carbon dioxide can be locked artificially into sea ice to eliminate the greenhouse effect.

8. Some scientists are not ready to give up the Milankovitch theory though they haven't figured out which mechanisms amplify the changes in solar heating.

9. Both Edwards and Ehrlich believe that there is no practical way to test when the solar temperature oscillation begins and when ends.

Questions 10-14

Complete the notes below.

Choose one suitable word from the Reading Passage above for each answer.

Write your answers in boxes 10-14 on your answer sheet.

The standard view assumes that the opposing pressures of gravity and nuclear fusions hold the temperature ...10...in the sun's interior, but the slight changes in the earth's ...11... alter the temperature on the earth and cause ice ages every 100,000 years. A British scientist, however, challenges this view by claiming that the internal solar magnetic ...12... can induce the temperature oscillations in the sun's interior. The sun's core temperature oscillates around its average temperature in ...13... lasting either 100,000 or 41,000 years. And the ...14... interactions within the sun's magnetic field could flip the fluctuations from one cycle length to the other, which explains why the ice ages changed frequency a million years ago.

new weapon to fight cancer

1. British scientists are preparing to launch trials of a radical new way to fight cancer, which kills tumours by infecting them with viruses like the common cold.

2. If successful, virus therapy could eventually form a third pillar alongside radiotherapy and chemotherapy in the standard arsenal against cancer, while avoiding some of the debilitating side-effects.

3. Leonard Seymour, a professor of gene therapy at Oxford University, who has been working on the virus therapy with colleagues in London and the US, will lead the trials later this year. Cancer Research UK said yesterday that it was excited by the potential of Prof Seymour’s pioneering techniques.

4. One of the country’s leading geneticists, Prof Seymour has been working with viruses that kill cancer cells directly, while avoiding harm to healthy tissue. "In principle, you’ve got something which could be many times more effective than regular chemotherapy," he said.

5. Cancer-killing viruses exploit the fact that cancer cells suppress the body’s local immune system. "If a cancer doesn’t do that, the immune system wipes it out. If you can get a virus into a tumour, viruses find them a very good place to be because there’s no immune system to stop them replicating. You can regard it as the cancer’s Achilles’ heel."

6. Only a small amount of the virus needs to get to the cancer. "They replicate, you get a million copies in each cell and the cell bursts and they infect the tumour cells adjacent and repeat the process," said Prof Seymour.

7. Preliminary research on mice shows that the viruses work well on tumours resistant to standard cancer drugs. "It’s an interesting possibility that they may have an advantage in killing drug-resistant tumours, which could be quite different to anything we’ve had before."

8. Researchers have known for some time that viruses can kill tumour cells and some aspects of the work have already been published in scientific journals. American scientists have previously injected viruses directly into tumours but this technique will not work if the cancer is inaccessible or has spread throughout the body.

9. Prof Seymour’s innovative solution is to mask the virus from the body’s immune system, effectively allowing the viruses to do what chemotherapy drugs do - spread through the blood and reach tumours wherever they are. The big hurdle has always been to find a way to deliver viruses to tumours via the bloodstream without the body’s immune system destroying them on the way.

10. "What we’ve done is make chemical modifications to the virus to put a polymer coat around it - it’s a stealth virus when you inject it," he said.

11. After the stealth virus infects the tumour, it replicates, but the copies do not have the chemical modifications. If they escape from the tumour, the copies will be quickly recognised and mopped up by the body’s immune system.

12. The therapy would be especially useful for secondary cancers, called metastases, which sometimes spread around the body after the first tumour appears. "There’s an awful statistic of patients in the west ... with malignant cancers; 75% of them go on to die from metastases," said Prof Seymour.

13. Two viruses are likely to be examined in the first clinical trials: adenovirus, which normally causes a cold-like illness, and vaccinia, which causes cowpox and is also used in the vaccine against smallpox. For safety reasons, both will be disabled to make them less pathogenic in the trial, but Prof Seymour said he eventually hopes to use natural viruses.

14. The first trials will use uncoated adenovirus and vaccinia and will be delivered locally to liver tumours, in order to establish whether the treatment is safe in humans and what dose of virus will be needed. Several more years of trials will be needed, eventually also on the polymer-coated viruses, before the therapy can be considered for use in the NHS. Though the approach will be examined at first for cancers that do not respond to conventional treatments, Prof Seymour hopes that one day it might be applied to all cancers.

Questions 1-6

Do the following statements agree with the information given in the reading passage? For questions 1-6 write

TRUE if the statement agrees with the information

FALSE if the statement contradicts the information

NOT GIVEN if there is no information on this in the passage

1.Virus therapy, if successful, has an advantage in eliminating side-effects.

2.Cancer Research UK is quite hopeful about Professor Seymour’s work on the virus therapy.

3.Virus can kill cancer cells and stop them from growing again.

4.Cancer’s Achilles’ heel refers to the fact that virus may stay safely in a tumor and replicate.

5.To infect the cancer cells, a good deal of viruses should be injected into the tumor.

6.Researches on animals indicate that virus could be used as a new way to treat drug-resistant tumors.

Question 7-9

Based on the reading passage, choose the appropriate letter from A-D for each answer.

7.Information about researches on viruses killing tumor cells can be found

(A) on TV

(B) in magazines

(C) on internet

(D) in newspapers

8.To treat tumors spreading out in body, researchers try to

(A) change the body’ immune system

(B) inject chemotherapy drugs into bloodstream.

(C) increase the amount of injection

(D) disguise the viruses on the way to tumors.

9.When the chemical modified virus in tumor replicates, the copies

(A) will soon escape from the tumor and spread out.

(B) will be wiped out by the body’s immune system.

(C) will be immediately recognized by the researchers.

(D) will eventually stop the tumor from spreading out.

Questions 10-13

Complete the sentences below. Choose your answers from the list of words. You can only use each word once.

NB There are more words in the list than spaces so you will not use them all.

In the first clinical trials, scientists will try to ……10…… adenovirus and vaccinia, so both the viruses will be less pathogenic than the ……11…….These uncoated viruses will be applied directly to certain areas to confirm safety on human beings and the right ……12…… needed. The experiments will firstly be ……13……to the treatment of certain cancers

Felicity Lawrence

Thursday December 28, 2006

The Guardian

1. Consumers are to be presented with two rival new year advertising campaigns as the Food Standards Agency goes public in its battle with the industry over the labelling of unhealthy foods.

2. The Guardian has learned that the FSA will launch a series of 10-second television adverts in January telling shoppers how to follow a red, amber and green traffic light labelling system on the front of food packs, which is designed to tackle Britain’s obesity epidemic.

3. The campaign is a direct response to a concerted attempt by leading food manufacturers and retailers, including Kellogg’s and Tesco, to derail the system. The industry fears that traffic lights would demonise entire categories of foods and could seriously damage the market for those that are fatty, salty or high in sugar.

4. The UK market for breakfast cereals is worth £1.27bn a year and the manufacturers fear it will be severely dented if red light labels are put on packaging drawing attention to the fact that the majority are high in salt and/or sugar.

5. The industry is planning a major marketing campaign for a competing labelling system which avoids colour-coding in favour of information about the percentage of "guideline daily amounts" (GDAs) of fat, salt and sugar contained in their products.

6. The battle for the nation’s diet comes as new rules on television advertising come into force in January which will bar adverts for unhealthy foods from commercial breaks during programmes aimed at children. Sources at the TV regulators are braced for a legal challenge from the industry and have described the lobbying efforts to block any new ad ban or colour-coded labelling as "the most ferocious we’ve ever experienced".

7. Ofcom’s chief executive, Ed Richards, said: "We are prepared to face up to any legal action from the industry, but we very much hope it will not be necessary." The FSA said it was expecting an onslaught from the industry in January. Senior FSA officials said the manufacturers’ efforts to undermine its proposals on labelling could threaten the agency’s credibility.

8. Terrence Collis, FSA director of communications, dismissed claims that the proposals were not based on science. "We have some of the most respected scientists in Europe, both within the FSA and in our independent advisory committees. It is unjustified and nonsensical to attack the FSA’s scientific reputation and to try to undermine its credibility."

9. The FSA is understood to have briefed its ad agency, United, before Christmas, and will aim to air ads that are "non-confrontational, humorous and factual" as a counterweight to industry’s efforts about the same time. The agency, however, will have a tiny fraction of the budget available to the industry.

10. Gavin Neath, chairman of Unilever UK and president of the Food and Drink Federation, has said that the industry has made enormous progress but could not accept red "stop" signs on its food.

11. Alastair Sykes, chief executive of Nestlé UK, said that under the FSA proposals all his company’s confectionery and most of its cereals would score a red. "Are we saying people shouldn’t eat confectionery? We’re driven by consumers and what they want, and much of what we do has been to make our products healthier," he said.

12. Chris Wermann, director of communications at Kellogg’s, said: "In principle we could never accept traffic light labelling."

13. The rival labelling scheme introduced by Kellogg’s, Danone, Unilever, Nestlé, Kraft and Tesco and now favoured by 21 manufacturers, uses an industry-devised system based on identifying GDAs of key nutrients. Tesco says it has tested both traffic lights and GDA labels in its stores and that the latter increased sales of healthier foods.

14. But the FSA said it could not live with this GDA system alone because it was "not scientific" or easy for shoppers to understand at a glance.

Questions 1-6

Answer the questions below using NO MORE THAN THREE WORDS from the passage for each answer.

1. When will instructions be given on reading the color-coded labels?

2. Where can customers find the red light labels?

3. What problem is the FSA trying to handle with the labeling system?

4. Which product sells well but may not be healthy?

5. What information, according to the manufacturers, can be labeled on products?

6. What can not be advertised during children’s programmes?

Questions 7-13

Use the information in the text to match the people (listed A-E) with the opinions (listed 7-13) below. Write the appropriate letter (A-E) for questions 1-7.

NB You may use any letter more than once.

A Ed Richard

B Terrence Collis

C Gavin Neath

D Alastair Sykes

E Chris Wermann

7. Generally we will not agree to use the red light labels.

8. It is unreasonable to doubt if FSA is trustworthy.

9. We are trying to meet our consumers’ needs.

10. The food industry has been improving greatly.

11. The color-coded labeling system is scientific.

12. Our products will be labeled unhealthy by the FSA.

13. We are ready to confront the manufacturers.

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