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For many people today, reading is no longer relaxation. In (51) a job or advancing in one, the abi...
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Intelligentcardoorclampsupwhendanger’saboutAccidentscausedbycardoorsbeingopenedintothepathofoncomingvehiclesorcyclistsarecommonincities.Buttheseincidentscouldbecomeathingofthepastifdoorsthatreacttopotentialimpactscatchon.ThecreativeideaofMichaelGrafatBMWandMichaelStrolz’steamattheTechnicalUniversityofMunichthehaptic-technologythatgivestactilefeedback-doorscouldcutbothroadinjuriesandrepairbillstheysay.Thecurrentprototypelookslikeanormalcardoorbutanextrametalbarrunsthroughitscentreandconnectstothecar’sframebetweenthehinges.Innormalmodethebarmovesfreelyanddoesn’taffectthedoor’smovement.Howeverifsensorsdetectanearbyobstacleatthesametimeasanaccelerometerdetectsanattempttoopenthedoorthedoor’sswingisrestrictedbyalinearmotorattachedtothebar.Topassonmoreinformationtotheusertheamountofdoorresistanceisinproportiontotheproximityofanobject-forexampleyoumightswingadoorhalfwayopenwithoutproblemsbeforeitgetsstifferasitnearsalamppost.Thecurrentprototypeusessupersonicsensorstospotdangersbutbecausetheyhavealimitedfieldofviewthenextversionwillusecamerasthatcanspan180°saysStrolz.Thenwewillbeabletosensethecompleteworkspaceofthedooranddetectpeoplewalkingbythecarorcyclingtowardsithesays.Reactionsfrom16volunteerswhotriedthenewdooratBMW’sMunichresearchcentrehavebeenencouragingtheteamtoldarecentconferenceonhapticsinSaltLakeCityUtah.ThetechnologyismatureenoughthatacarfactorycouldbepumpingitoutincarswithinayearsaysStrolz.Thebasicmechanismislikeonealreadyfeaturedinsomecars-forexampletaxiswithautomaticpassengerdoors.HoweverBMWisyettomakeanydecisiononwhethertorollitout.Whatbenefitscanthenewtechnologypossiblybringaccordingtothepassage
Inrecentyearsanewfarmingrevolutionhasbegunonethatinvolvesthemanipulationoflifeatafundamentallevel—thegene.Thestudyofgeneticshas51anewindustrycalledbiotcehnology.Asthenamesuggestsit52biologyandmoderntechnologythroughsuchtechniquesasgeneticengineering.Someofthenewbiotechcompaniesspecializeinagricultureandareworkingfeverishlyto53seedsthatgiveahighyieldthat54diseasesdroughtandfrostandthatreducetheneedforhazardouschemicalsIfsuchgoalscouldbeachieveditwouldbemost55.Butsomehaveraisedconcernsaboutgeneticallyengineeredcrops.Innaturegeneticdiversityiscreatedwithincertain56.Arosecanbecrossedwithadifferentkindofrosebutarosewillnevercrosswithapotato.Geneticengineering57usuallyinvolvestakinggenesfromonespeciesandinsertingthemintoanotherinanattempttotransferadesiredcharacteristic.Thiscouldmeanforexampleselectingagenewhichleadstotheproductionofachemicalwithanti-freeze58fromanarticfishandinsertingitintoapotatoorstrawberrytomakeitfrostresistantinessencethenbiotechnologyallowshumansto59thegeneticwallsthatseparatespecies.Justlikethegreenrevolution60somecallthegenerevolutioncontributestotheproblemofgeneticuniformity-somesayevenmoreso61geneticistscanemploytechniquessuchascloningand62culture培养andprocessesthatproduceperfectly63copies.Concernsabouttheerosionofbiodiversitythereforeremain.Geneticallyalteredplantshoweverraisenew64suchastheeffectsthattheymayhaveonusandtheenvironment.Wearetlyingblindlyintoaneweraofagriculturalbiotechnologywithhighhopesfewconstraintsandlittleideaofthepotential65saidsciencewriterJeremyRifkin.
1.TheGreatWallofChinaWallsandwallbuildinghaveplayedaveryimportantroleinChineseculture.Thesepeoplefromthedimmistsofprehistoryhavebeenwall-conscious;fromtheNeolithicperiod新石器时代-whenramparts防御土墙ofpoundedearthwereused-totheCommunistRevolutionwallswereanessentialpartofanyvillage.46ThenameforcityinChinesech’engmeanswallandoverthesewalledcitiesvillageshousesandtemplespresidesthegodofwallsandmountswhosedutieswereandstillaretoprotectandberesponsibleforthewelfareoftheinhabitants.47HoweveritisindeedacommonmistaketoperceivetheGreatWallasasinglearchitecturalstructureanditwouldalsobeerroneoustoassumethatitwasbuiltduringasingledynasty.Forthebuildingofthewallspannedthevariousdynastiesandeachofthesedynastiessomehowcontributedtotherefurbishingandtheconstructionofawallwhosefoundationshadbeenlaidmanycenturiesago.48Especiallythreeofthesestates:theCh’intheChaoandtheYencorrespondingrespectivelytothemodemprovincesofShensiShanziandHopeioverandabovebuildingwallsthatsurroundedtheirkingdomsalsolaidthefoundationsonwhichCh’inShihHuangDiwouldbuildhisfirstcontinuousGreatWall.49Throughoutthecenturiesmanysettlementswereestablishedalongthenewborder.Thegarrison驻军troopswereinstructedtoreclaimwastelandandtoplantcropsonitroadsandcanalswerebuilttomentionjustafewoftheworkscarriedout.50BuildersgarrisonsartisansfarmersandpeasantsleftbehindatrailofobjectsincludinginscribedtabletshouseholdarticlesandwrittenworkwhichhavebecomeextremelyvaluablearchaeologicalevidencetothestudyofdefenseinstitutionsoftheGreatWallandtheeverydaylifeofthesepeoplewholivedanddiedalongthewall.A.Notonlytownsandvillages;thehousesandthetempleswithinthemweresomehowwalledandthehousesalsohadnowindowsoverlookingthestreetthusgivingthefeelingofwanderingaroundahugemaze迷宫.B.Alltheseundertakingsgreatlyhelpedtoincreasethecountry’stradeandculturalexchangeswithmanyremoteareasandalsowiththesoutherncentralandwesternpartsofAsia-theformationoftheSilkRoute.C.Thusagreatandextremelylaborioustasksuchasconstructingawallwhichwassupposedtorunthroughoutthecountrymustnothaveseemedsuchanabsurdity谬论.D.TheconstructionoftheGreatWallisresponsibleforalargenumberofdeathsandavastamountofdestructioninvariousplaces.E.ItwasduringthefourthandthirdcenturyB.C.thateachwarringstatestartedbuildingwallstoprotecttheirkingdomsbothagainstoneanotherandagainstthenorthernnomads游牧民.F.TherolethattheGreatWallplayedinthegrowthofChineseeconomywasanimportanton
Inrecentyearsanewfarmingrevolutionhasbegunonethatinvolvesthemanipulationoflifeatafundamentallevel—thegene.Thestudyofgeneticshas51anewindustrycalledbiotcehnology.Asthenamesuggestsit52biologyandmoderntechnologythroughsuchtechniquesasgeneticengineering.Someofthenewbiotechcompaniesspecializeinagricultureandareworkingfeverishlyto53seedsthatgiveahighyieldthat54diseasesdroughtandfrostandthatreducetheneedforhazardouschemicalsIfsuchgoalscouldbeachieveditwouldbemost55.Butsomehaveraisedconcernsaboutgeneticallyengineeredcrops.Innaturegeneticdiversityiscreatedwithincertain56.Arosecanbecrossedwithadifferentkindofrosebutarosewillnevercrosswithapotato.Geneticengineering57usuallyinvolvestakinggenesfromonespeciesandinsertingthemintoanotherinanattempttotransferadesiredcharacteristic.Thiscouldmeanforexampleselectingagenewhichleadstotheproductionofachemicalwithanti-freeze58fromanarticfishandinsertingitintoapotatoorstrawberrytomakeitfrostresistantinessencethenbiotechnologyallowshumansto59thegeneticwallsthatseparatespecies.Justlikethegreenrevolution60somecallthegenerevolutioncontributestotheproblemofgeneticuniformity-somesayevenmoreso61geneticistscanemploytechniquessuchascloningand62culture培养andprocessesthatproduceperfectly63copies.Concernsabouttheerosionofbiodiversitythereforeremain.Geneticallyalteredplantshoweverraisenew64suchastheeffectsthattheymayhaveonusandtheenvironment.Wearetlyingblindlyintoaneweraofagriculturalbiotechnologywithhighhopesfewconstraintsandlittleideaofthepotential65saidsciencewriterJeremyRifkin.
Theprojectwascompletedontimebecausethecooperationbetweenthetwocompames.
Theseprogrammesareofimmenseimportancetotheyoungstudents.
2.SpaceJunkCosmos2251wasanordinarysatellitedesignedtotransmitsignalsacrossthevastRussianlandmass.Launchedin1993itwouldappearevery90minutesorsooverthenorthernskiesrelayelectronicblipsofinformationamonganetworkofsatellitesandgroundstationslikeahockeyplayerpassingthepuckanddisappearoverthesouthernhorizon.Iridium33launchedforMotorolain1997didsomethingsimilarthoughittookaslightlydifferentorbitthatbroughtitclosesttoEarthduringitspassoverNorthAmerica.Foryearsthetwosatellitescircledtheplanetmindingtheirownbusinessnevercomingwithinathousandkilometersofoneanother.ThensomethinghappenedtoCosmos.Itmayhavesprungasmallleak;perhapsitstruckatinyasteroidorapieceofdebris.NobodyknowsforsurebutforonereasonoranotherCosmosdriftedoffcourse.T.S.KelsoanaeronauticsexpertatAnalyticalGraphicswhichprovidessatellite-trackingservicestoNASAnoticedthattheorbitsofCosmosandIridiumwerebringingthetwosatellitesclosertoeachotherallthetime.InFebruaryheissuedawarningthattheywouldpasswithinakilometerofoneanothertiewasright.OnFeb.10MotorolalosttrackofIridium’ssignal.OverthenextfewdaysKelsoandotherssurmisedthatwhatmanyhadfearedforyearshadfinallycometopass:twointactsatelliteshadcollidedheadon.Theconsequencesgofarbeyondmerelythelossoftwopiecesofproperty.Eachsatelliteweighedmorethanhalfametrictonandwasmovingat7.5kilometerspersecond.Theresultingexplosionwascatastrophicgeneratingamassivecloudofcosmicdebris—perhapsl00000piecesofjunkbiggerthanonecentimeterindiameterestimatesDavidWrightaspaceexpertattheUnionofConcernedScientists.Inonestroketheaccidentincreasedbynearlyathirdthenumberofstrayobjectsinthecrucial700-to-900-kilometerhandknownaslowEarthorbitLEO.Thejunkcloudwilleventuallydispersearoundtheentireplanetlikeashroud.Theeventservedasawake-upcalltospaceplanners.Insuranceratesforthe$18billionworthofactivecommercialsatellitesnowinorbithavetickedupwardsby10to20percentsincetheaccident.Governmentstoohavegrowntorelyonnetworksofsatellitestogatherintelligencedirectweaponssystemsforecastclimateandweatherchangesmonitoragricultureandoperatecommunicationsandnavigationsystems.Expertscalculatethatdebriswillnowstrikeoneofthe900activesatellitesinLEOeverytwoorthreeyears.Forthefirsttimejunkisthesinglebiggestriskfactortoequipmentinsomeorbits.AmongtheorbitalthreatsaretwoformerSovietnuclearreactors.EventheInternationalSpaceStationmayonedaybeatriskasdebrisslowlydescendstoits350-kilometerorbit.Cosmos2251andIridium33arecommercialsatelliteswhosharethesameorbit.
Inrecentyearsanewfarmingrevolutionhasbegunonethatinvolvesthemanipulationoflifeatafundamentallevel—thegene.Thestudyofgeneticshas51anewindustrycalledbiotcehnology.Asthenamesuggestsit52biologyandmoderntechnologythroughsuchtechniquesasgeneticengineering.Someofthenewbiotechcompaniesspecializeinagricultureandareworkingfeverishlyto53seedsthatgiveahighyieldthat54diseasesdroughtandfrostandthatreducetheneedforhazardouschemicalsIfsuchgoalscouldbeachieveditwouldbemost55.Butsomehaveraisedconcernsaboutgeneticallyengineeredcrops.Innaturegeneticdiversityiscreatedwithincertain56.Arosecanbecrossedwithadifferentkindofrosebutarosewillnevercrosswithapotato.Geneticengineering57usuallyinvolvestakinggenesfromonespeciesandinsertingthemintoanotherinanattempttotransferadesiredcharacteristic.Thiscouldmeanforexampleselectingagenewhichleadstotheproductionofachemicalwithanti-freeze58fromanarticfishandinsertingitintoapotatoorstrawberrytomakeitfrostresistantinessencethenbiotechnologyallowshumansto59thegeneticwallsthatseparatespecies.Justlikethegreenrevolution60somecallthegenerevolutioncontributestotheproblemofgeneticuniformity-somesayevenmoreso61geneticistscanemploytechniquessuchascloningand62culture培养andprocessesthatproduceperfectly63copies.Concernsabouttheerosionofbiodiversitythereforeremain.Geneticallyalteredplantshoweverraisenew64suchastheeffectsthattheymayhaveonusandtheenvironment.Wearetlyingblindlyintoaneweraofagriculturalbiotechnologywithhighhopesfewconstraintsandlittleideaofthepotential65saidsciencewriterJeremyRifkin.
Don’tTreatAnimalsasFurryTest-tubesMostofusagreethatthereisamoralobligationtominimizethesufferingofanycaptiveanimals.Inadditiontherearenumerousself-servingreasonswhyweshouldrespectthewelfareofourcaptivecompanions.Howevertheimpactofpooranimalwelfareonthequalityofanimalsciencealwaysconcernsascientistthemost.Rodents灵长类动物makeupover80%oftheanimalsusedinscientificproceduresandmostarekeptinsmallbarrencages.Suchhousingisknowntoconstrainnormaldevelopmentaffectingthestructureandfunctionofadultrodentbrains.Theserodentsmayspend50%ofwakinghoursperformingrepetitiveactivitieswithoutapparentpurpose.Thisabnormalbehaviorislikelytoreflectwhatisgoingoninsidethebody.AsethnologistHannoWfirbeloftheJustusLiebigUniversityofGiessenGermanyputsitThepointthattheenvironmentmightchangebehaviorbutitdoesn’tchangebiologyisridiculous.Everybehaviorhasaphysiologicalbackground.Ifwelfareaffectsbehaviorandthereforebiologyitwillaffectscientificoutcomes.Aslongaswecontinuetotreatexperimentalanimalsassimplefurrytest-tubesignoringtheirabilitiesandneedsweendangerthequalityoftheworkwedowiththem.SohowcanweimprovelifeforotherspecieswhenwecannotexperienceitastheydoWe’dbetterasktheanimals.Askthemwhattheyneedandwhatcausesthemsufferingthroughcarefullydesignedpreferencetestsandin-depthbehaviouralresearch.Scientistshavealreadybegunthistaskandhavebeentoldsomeimportantandunexpectedfactsbytheirstudysubjects.Byconsistentlyself-medicatingwithpainkillersbroilerchickens嫩鸡havetoldusthattheyareinchronicpain.Bymovingabarriertwicetheirsizemink水貂havetoldusthatwaterbathsarethemostimportantenrichmentforthem.Byonlystoppingtheirfruitlessstereotypicdiggingincertaincircumstancesgerbils沙鼠havetoldusthattheyneedtobeabletosleepintunnelednest-boxes.Bybehavingnormallyagainstarlingshavetoldusthattheyneedhighfrequencylightbulbs.Whatarescientistsmostconcernedaboutaccordingtothefirstparagraph
Halfofworld’sprimatesfaceextinctionAlmost50%oftheworld’s634primate灵长类动物speciesfaceextinctionaccordingtoareportfromtheInternationalUnionfortheConservationofNature.Habitatlossisamajorcausebutmanymonkeysandapesarebeinghuntedtoextinctionforfoodespeciallyinforestsofsouth-eastAsia.It’scheapertogointotheforestandkillamonkeythantoraiseachickensaysJean-ChristopheriedeputyheadoftheIUCN’sspeciesprogrammeandaco—authorofthereport.We’veraisedconcernsforyearsaboutprimatesbeingindangerbutnowwehavesoliddatatoshowthesituationisfarmoreseverethanweimaginedsaysRussellMittermeierpresidentofConservationInternationalwhichco-fundedthestudy.TheareasmostatriskareinVietnamandCambodiawhere90%ofspeciesarebeingdriventoextinctionbydemandformonkeymeatandbabymonkeysaspets.Mostacutelyaffectedaremedium-sizedmonkeyssuchasgibbons长臂猿leafmonkeysandlangurswhichareeasyforhunterstotrackdownandkillbecauseoftheirsizeandthenoisetheymake.InSouthAmerica.spidermonkeysandcapuchinmonkeys卷尾猴havebeenhithardest.InAfricaredcolobusmonkeysarenowcriticallyendangered.Elevenofthe13speciesassessedwerelistedascriticallyendangeredorendangered.Twomayalreadybeextinct.AmongtheAfricanspeciesthegreatapessuchasgorillas大猩猩andbonoboshavealwaystendedtograbthelimelightandeventhoughtthey’redeeplythreateneditissmallerprimatessuchastheredcolobusthatcoulddieoutfirstsaysRichardWranghampresidentoftheInternationalPrimatologicalSociety.HugepoliticaleffortsareneedednowtoreversetheimpendinglossesofthreatenedspeciessaysVid.What’sneededisnationallegislationtoprotectbiodiversitycreationofprotectedareaswithdedicatedstaffcrackdownsoncorruptionandcaptivebreedingprogrammeshesays.Butitwillbedifficulttohaltandreversethedamagedonebyhabitatdestructionandthehunters.Oncehabitatisgoneanimalshavenowheretogo.Alsokillingprimatesrapidlydepletespopulationsbecausetheyhavefeweryoungthanmanyothermammalsandtakemuchlongertobreedandraisefamilies.90%ofthespeciesinVietnamandCambodiaarebeingdriventoextinctionbecause
Inrecentyearsanewfarmingrevolutionhasbegunonethatinvolvesthemanipulationoflifeatafundamentallevel—thegene.Thestudyofgeneticshas51anewindustrycalledbiotcehnology.Asthenamesuggestsit52biologyandmoderntechnologythroughsuchtechniquesasgeneticengineering.Someofthenewbiotechcompaniesspecializeinagricultureandareworkingfeverishlyto53seedsthatgiveahighyieldthat54diseasesdroughtandfrostandthatreducetheneedforhazardouschemicalsIfsuchgoalscouldbeachieveditwouldbemost55.Butsomehaveraisedconcernsaboutgeneticallyengineeredcrops.Innaturegeneticdiversityiscreatedwithincertain56.Arosecanbecrossedwithadifferentkindofrosebutarosewillnevercrosswithapotato.Geneticengineering57usuallyinvolvestakinggenesfromonespeciesandinsertingthemintoanotherinanattempttotransferadesiredcharacteristic.Thiscouldmeanforexampleselectingagenewhichleadstotheproductionofachemicalwithanti-freeze58fromanarticfishandinsertingitintoapotatoorstrawberrytomakeitfrostresistantinessencethenbiotechnologyallowshumansto59thegeneticwallsthatseparatespecies.Justlikethegreenrevolution60somecallthegenerevolutioncontributestotheproblemofgeneticuniformity-somesayevenmoreso61geneticistscanemploytechniquessuchascloningand62culture培养andprocessesthatproduceperfectly63copies.Concernsabouttheerosionofbiodiversitythereforeremain.Geneticallyalteredplantshoweverraisenew64suchastheeffectsthattheymayhaveonusandtheenvironment.Wearetlyingblindlyintoaneweraofagriculturalbiotechnologywithhighhopesfewconstraintsandlittleideaofthepotential65saidsciencewriterJeremyRifkin.
Inrecentyearsanewfarmingrevolutionhasbegunonethatinvolvesthemanipulationoflifeatafundamentallevel—thegene.Thestudyofgeneticshas51anewindustrycalledbiotcehnology.Asthenamesuggestsit52biologyandmoderntechnologythroughsuchtechniquesasgeneticengineering.Someofthenewbiotechcompaniesspecializeinagricultureandareworkingfeverishlyto53seedsthatgiveahighyieldthat54diseasesdroughtandfrostandthatreducetheneedforhazardouschemicalsIfsuchgoalscouldbeachieveditwouldbemost55.Butsomehaveraisedconcernsaboutgeneticallyengineeredcrops.Innaturegeneticdiversityiscreatedwithincertain56.Arosecanbecrossedwithadifferentkindofrosebutarosewillnevercrosswithapotato.Geneticengineering57usuallyinvolvestakinggenesfromonespeciesandinsertingthemintoanotherinanattempttotransferadesiredcharacteristic.Thiscouldmeanforexampleselectingagenewhichleadstotheproductionofachemicalwithanti-freeze58fromanarticfishandinsertingitintoapotatoorstrawberrytomakeitfrostresistantinessencethenbiotechnologyallowshumansto59thegeneticwallsthatseparatespecies.Justlikethegreenrevolution60somecallthegenerevolutioncontributestotheproblemofgeneticuniformity-somesayevenmoreso61geneticistscanemploytechniquessuchascloningand62culture培养andprocessesthatproduceperfectly63copies.Concernsabouttheerosionofbiodiversitythereforeremain.Geneticallyalteredplantshoweverraisenew64suchastheeffectsthattheymayhaveonusandtheenvironment.Wearetlyingblindlyintoaneweraofagriculturalbiotechnologywithhighhopesfewconstraintsandlittleideaofthepotential65saidsciencewriterJeremyRifkin.
Agreatdealhasbeendonetobetterthesituation
Halfofworld’sprimatesfaceextinctionAlmost50%oftheworld’s634primate灵长类动物speciesfaceextinctionaccordingtoareportfromtheInternationalUnionfortheConservationofNature.Habitatlossisamajorcausebutmanymonkeysandapesarebeinghuntedtoextinctionforfoodespeciallyinforestsofsouth-eastAsia.It’scheapertogointotheforestandkillamonkeythantoraiseachickensaysJean-ChristopheriedeputyheadoftheIUCN’sspeciesprogrammeandaco—authorofthereport.We’veraisedconcernsforyearsaboutprimatesbeingindangerbutnowwehavesoliddatatoshowthesituationisfarmoreseverethanweimaginedsaysRussellMittermeierpresidentofConservationInternationalwhichco-fundedthestudy.TheareasmostatriskareinVietnamandCambodiawhere90%ofspeciesarebeingdriventoextinctionbydemandformonkeymeatandbabymonkeysaspets.Mostacutelyaffectedaremedium-sizedmonkeyssuchasgibbons长臂猿leafmonkeysandlangurswhichareeasyforhunterstotrackdownandkillbecauseoftheirsizeandthenoisetheymake.InSouthAmerica.spidermonkeysandcapuchinmonkeys卷尾猴havebeenhithardest.InAfricaredcolobusmonkeysarenowcriticallyendangered.Elevenofthe13speciesassessedwerelistedascriticallyendangeredorendangered.Twomayalreadybeextinct.AmongtheAfricanspeciesthegreatapessuchasgorillas大猩猩andbonoboshavealwaystendedtograbthelimelightandeventhoughtthey’redeeplythreateneditissmallerprimatessuchastheredcolobusthatcoulddieoutfirstsaysRichardWranghampresidentoftheInternationalPrimatologicalSociety.HugepoliticaleffortsareneedednowtoreversetheimpendinglossesofthreatenedspeciessaysVid.What’sneededisnationallegislationtoprotectbiodiversitycreationofprotectedareaswithdedicatedstaffcrackdownsoncorruptionandcaptivebreedingprogrammeshesays.Butitwillbedifficulttohaltandreversethedamagedonebyhabitatdestructionandthehunters.Oncehabitatisgoneanimalshavenowheretogo.Alsokillingprimatesrapidlydepletespopulationsbecausetheyhavefeweryoungthanmanyothermammalsandtakemuchlongertobreedandraisefamilies.WhichofthefollowingisnotaneffortsuggestedbyViétoreducethethreattospecies
1.TheGreatWallofChinaWallsandwallbuildinghaveplayedaveryimportantroleinChineseculture.Thesepeoplefromthedimmistsofprehistoryhavebeenwall-conscious;fromtheNeolithicperiod新石器时代-whenramparts防御土墙ofpoundedearthwereused-totheCommunistRevolutionwallswereanessentialpartofanyvillage.46ThenameforcityinChinesech’engmeanswallandoverthesewalledcitiesvillageshousesandtemplespresidesthegodofwallsandmountswhosedutieswereandstillaretoprotectandberesponsibleforthewelfareoftheinhabitants.47HoweveritisindeedacommonmistaketoperceivetheGreatWallasasinglearchitecturalstructureanditwouldalsobeerroneoustoassumethatitwasbuiltduringasingledynasty.Forthebuildingofthewallspannedthevariousdynastiesandeachofthesedynastiessomehowcontributedtotherefurbishingandtheconstructionofawallwhosefoundationshadbeenlaidmanycenturiesago.48Especiallythreeofthesestates:theCh’intheChaoandtheYencorrespondingrespectivelytothemodemprovincesofShensiShanziandHopeioverandabovebuildingwallsthatsurroundedtheirkingdomsalsolaidthefoundationsonwhichCh’inShihHuangDiwouldbuildhisfirstcontinuousGreatWall.49Throughoutthecenturiesmanysettlementswereestablishedalongthenewborder.Thegarrison驻军troopswereinstructedtoreclaimwastelandandtoplantcropsonitroadsandcanalswerebuilttomentionjustafewoftheworkscarriedout.50BuildersgarrisonsartisansfarmersandpeasantsleftbehindatrailofobjectsincludinginscribedtabletshouseholdarticlesandwrittenworkwhichhavebecomeextremelyvaluablearchaeologicalevidencetothestudyofdefenseinstitutionsoftheGreatWallandtheeverydaylifeofthesepeoplewholivedanddiedalongthewall.A.Notonlytownsandvillages;thehousesandthetempleswithinthemweresomehowwalledandthehousesalsohadnowindowsoverlookingthestreetthusgivingthefeelingofwanderingaroundahugemaze迷宫.B.Alltheseundertakingsgreatlyhelpedtoincreasethecountry’stradeandculturalexchangeswithmanyremoteareasandalsowiththesoutherncentralandwesternpartsofAsia-theformationoftheSilkRoute.C.Thusagreatandextremelylaborioustasksuchasconstructingawallwhichwassupposedtorunthroughoutthecountrymustnothaveseemedsuchanabsurdity谬论.D.TheconstructionoftheGreatWallisresponsibleforalargenumberofdeathsandavastamountofdestructioninvariousplaces.E.ItwasduringthefourthandthirdcenturyB.C.thateachwarringstatestartedbuildingwallstoprotecttheirkingdomsbothagainstoneanotherandagainstthenorthernnomads游牧民.F.TherolethattheGreatWallplayedinthegrowthofChineseeconomywasanimportanton
Inrecentyearsanewfarmingrevolutionhasbegunonethatinvolvesthemanipulationoflifeatafundamentallevel—thegene.Thestudyofgeneticshas51anewindustrycalledbiotcehnology.Asthenamesuggestsit52biologyandmoderntechnologythroughsuchtechniquesasgeneticengineering.Someofthenewbiotechcompaniesspecializeinagricultureandareworkingfeverishlyto53seedsthatgiveahighyieldthat54diseasesdroughtandfrostandthatreducetheneedforhazardouschemicalsIfsuchgoalscouldbeachieveditwouldbemost55.Butsomehaveraisedconcernsaboutgeneticallyengineeredcrops.Innaturegeneticdiversityiscreatedwithincertain56.Arosecanbecrossedwithadifferentkindofrosebutarosewillnevercrosswithapotato.Geneticengineering57usuallyinvolvestakinggenesfromonespeciesandinsertingthemintoanotherinanattempttotransferadesiredcharacteristic.Thiscouldmeanforexampleselectingagenewhichleadstotheproductionofachemicalwithanti-freeze58fromanarticfishandinsertingitintoapotatoorstrawberrytomakeitfrostresistantinessencethenbiotechnologyallowshumansto59thegeneticwallsthatseparatespecies.Justlikethegreenrevolution60somecallthegenerevolutioncontributestotheproblemofgeneticuniformity-somesayevenmoreso61geneticistscanemploytechniquessuchascloningand62culture培养andprocessesthatproduceperfectly63copies.Concernsabouttheerosionofbiodiversitythereforeremain.Geneticallyalteredplantshoweverraisenew64suchastheeffectsthattheymayhaveonusandtheenvironment.Wearetlyingblindlyintoaneweraofagriculturalbiotechnologywithhighhopesfewconstraintsandlittleideaofthepotential65saidsciencewriterJeremyRifkin.
Don’tTreatAnimalsasFurryTest-tubesMostofusagreethatthereisamoralobligationtominimizethesufferingofanycaptiveanimals.Inadditiontherearenumerousself-servingreasonswhyweshouldrespectthewelfareofourcaptivecompanions.Howevertheimpactofpooranimalwelfareonthequalityofanimalsciencealwaysconcernsascientistthemost.Rodents灵长类动物makeupover80%oftheanimalsusedinscientificproceduresandmostarekeptinsmallbarrencages.Suchhousingisknowntoconstrainnormaldevelopmentaffectingthestructureandfunctionofadultrodentbrains.Theserodentsmayspend50%ofwakinghoursperformingrepetitiveactivitieswithoutapparentpurpose.Thisabnormalbehaviorislikelytoreflectwhatisgoingoninsidethebody.AsethnologistHannoWfirbeloftheJustusLiebigUniversityofGiessenGermanyputsitThepointthattheenvironmentmightchangebehaviorbutitdoesn’tchangebiologyisridiculous.Everybehaviorhasaphysiologicalbackground.Ifwelfareaffectsbehaviorandthereforebiologyitwillaffectscientificoutcomes.Aslongaswecontinuetotreatexperimentalanimalsassimplefurrytest-tubesignoringtheirabilitiesandneedsweendangerthequalityoftheworkwedowiththem.SohowcanweimprovelifeforotherspecieswhenwecannotexperienceitastheydoWe’dbetterasktheanimals.Askthemwhattheyneedandwhatcausesthemsufferingthroughcarefullydesignedpreferencetestsandin-depthbehaviouralresearch.Scientistshavealreadybegunthistaskandhavebeentoldsomeimportantandunexpectedfactsbytheirstudysubjects.Byconsistentlyself-medicatingwithpainkillersbroilerchickens嫩鸡havetoldusthattheyareinchronicpain.Bymovingabarriertwicetheirsizemink水貂havetoldusthatwaterbathsarethemostimportantenrichmentforthem.Byonlystoppingtheirfruitlessstereotypicdiggingincertaincircumstancesgerbils沙鼠havetoldusthattheyneedtobeabletosleepintunnelednest-boxes.Bybehavingnormallyagainstarlingshavetoldusthattheyneedhighfrequencylightbulbs.Whichofthefollowingistrueaboutscientists’discoveryaboutanimals’needsandsufferings
A.AShortHistoryofNamingHurricanesB.HarnessingtheHurricaneEnergyC.DifficultyinForecastingtheCourseofaHurricaneD.HugeEnergyStoredinaHurricaneE.ForecastingaHurricaneThroughSatelliteWatchingF.DifferentNamesfortheSameThingsParagraph2______.
A.AShortHistoryofNamingHurricanesB.HarnessingtheHurricaneEnergyC.DifficultyinForecastingtheCourseofaHurricaneD.HugeEnergyStoredinaHurricaneE.ForecastingaHurricaneThroughSatelliteWatchingF.DifferentNamesfortheSameThingsParagraph5______.
2.SpaceJunkCosmos2251wasanordinarysatellitedesignedtotransmitsignalsacrossthevastRussianlandmass.Launchedin1993itwouldappearevery90minutesorsooverthenorthernskiesrelayelectronicblipsofinformationamonganetworkofsatellitesandgroundstationslikeahockeyplayerpassingthepuckanddisappearoverthesouthernhorizon.Iridium33launchedforMotorolain1997didsomethingsimilarthoughittookaslightlydifferentorbitthatbroughtitclosesttoEarthduringitspassoverNorthAmerica.Foryearsthetwosatellitescircledtheplanetmindingtheirownbusinessnevercomingwithinathousandkilometersofoneanother.ThensomethinghappenedtoCosmos.Itmayhavesprungasmallleak;perhapsitstruckatinyasteroidorapieceofdebris.NobodyknowsforsurebutforonereasonoranotherCosmosdriftedoffcourse.T.S.KelsoanaeronauticsexpertatAnalyticalGraphicswhichprovidessatellite-trackingservicestoNASAnoticedthattheorbitsofCosmosandIridiumwerebringingthetwosatellitesclosertoeachotherallthetime.InFebruaryheissuedawarningthattheywouldpasswithinakilometerofoneanothertiewasright.OnFeb.10MotorolalosttrackofIridium’ssignal.OverthenextfewdaysKelsoandotherssurmisedthatwhatmanyhadfearedforyearshadfinallycometopass:twointactsatelliteshadcollidedheadon.Theconsequencesgofarbeyondmerelythelossoftwopiecesofproperty.Eachsatelliteweighedmorethanhalfametrictonandwasmovingat7.5kilometerspersecond.Theresultingexplosionwascatastrophicgeneratingamassivecloudofcosmicdebris—perhapsl00000piecesofjunkbiggerthanonecentimeterindiameterestimatesDavidWrightaspaceexpertattheUnionofConcernedScientists.Inonestroketheaccidentincreasedbynearlyathirdthenumberofstrayobjectsinthecrucial700-to-900-kilometerhandknownaslowEarthorbitLEO.Thejunkcloudwilleventuallydispersearoundtheentireplanetlikeashroud.Theeventservedasawake-upcalltospaceplanners.Insuranceratesforthe$18billionworthofactivecommercialsatellitesnowinorbithavetickedupwardsby10to20percentsincetheaccident.Governmentstoohavegrowntorelyonnetworksofsatellitestogatherintelligencedirectweaponssystemsforecastclimateandweatherchangesmonitoragricultureandoperatecommunicationsandnavigationsystems.Expertscalculatethatdebriswillnowstrikeoneofthe900activesatellitesinLEOeverytwoorthreeyears.Forthefirsttimejunkisthesinglebiggestriskfactortoequipmentinsomeorbits.AmongtheorbitalthreatsaretwoformerSovietnuclearreactors.EventheInternationalSpaceStationmayonedaybeatriskasdebrisslowlydescendstoits350-kilometerorbit.T.S.KelsofoundthatCosmosandIridiumwerecomingtoeachother.
2.SpaceJunkCosmos2251wasanordinarysatellitedesignedtotransmitsignalsacrossthevastRussianlandmass.Launchedin1993itwouldappearevery90minutesorsooverthenorthernskiesrelayelectronicblipsofinformationamonganetworkofsatellitesandgroundstationslikeahockeyplayerpassingthepuckanddisappearoverthesouthernhorizon.Iridium33launchedforMotorolain1997didsomethingsimilarthoughittookaslightlydifferentorbitthatbroughtitclosesttoEarthduringitspassoverNorthAmerica.Foryearsthetwosatellitescircledtheplanetmindingtheirownbusinessnevercomingwithinathousandkilometersofoneanother.ThensomethinghappenedtoCosmos.Itmayhavesprungasmallleak;perhapsitstruckatinyasteroidorapieceofdebris.NobodyknowsforsurebutforonereasonoranotherCosmosdriftedoffcourse.T.S.KelsoanaeronauticsexpertatAnalyticalGraphicswhichprovidessatellite-trackingservicestoNASAnoticedthattheorbitsofCosmosandIridiumwerebringingthetwosatellitesclosertoeachotherallthetime.InFebruaryheissuedawarningthattheywouldpasswithinakilometerofoneanothertiewasright.OnFeb.10MotorolalosttrackofIridium’ssignal.OverthenextfewdaysKelsoandotherssurmisedthatwhatmanyhadfearedforyearshadfinallycometopass:twointactsatelliteshadcollidedheadon.Theconsequencesgofarbeyondmerelythelossoftwopiecesofproperty.Eachsatelliteweighedmorethanhalfametrictonandwasmovingat7.5kilometerspersecond.Theresultingexplosionwascatastrophicgeneratingamassivecloudofcosmicdebris—perhapsl00000piecesofjunkbiggerthanonecentimeterindiameterestimatesDavidWrightaspaceexpertattheUnionofConcernedScientists.Inonestroketheaccidentincreasedbynearlyathirdthenumberofstrayobjectsinthecrucial700-to-900-kilometerhandknownaslowEarthorbitLEO.Thejunkcloudwilleventuallydispersearoundtheentireplanetlikeashroud.Theeventservedasawake-upcalltospaceplanners.Insuranceratesforthe$18billionworthofactivecommercialsatellitesnowinorbithavetickedupwardsby10to20percentsincetheaccident.Governmentstoohavegrowntorelyonnetworksofsatellitestogatherintelligencedirectweaponssystemsforecastclimateandweatherchangesmonitoragricultureandoperatecommunicationsandnavigationsystems.Expertscalculatethatdebriswillnowstrikeoneofthe900activesatellitesinLEOeverytwoorthreeyears.Forthefirsttimejunkisthesinglebiggestriskfactortoequipmentinsomeorbits.AmongtheorbitalthreatsaretwoformerSovietnuclearreactors.EventheInternationalSpaceStationmayonedaybeatriskasdebrisslowlydescendstoits350-kilometerorbit.Junkhasbecomethesinglebiggestthreattoequipmentinallorbits.
Thelittleboycan'tdiscriminatetherightthingfromthewrongone.
Inrecentyearsanewfarmingrevolutionhasbegunonethatinvolvesthemanipulationoflifeatafundamentallevel—thegene.Thestudyofgeneticshas51anewindustrycalledbiotcehnology.Asthenamesuggestsit52biologyandmoderntechnologythroughsuchtechniquesasgeneticengineering.Someofthenewbiotechcompaniesspecializeinagricultureandareworkingfeverishlyto53seedsthatgiveahighyieldthat54diseasesdroughtandfrostandthatreducetheneedforhazardouschemicalsIfsuchgoalscouldbeachieveditwouldbemost55.Butsomehaveraisedconcernsaboutgeneticallyengineeredcrops.Innaturegeneticdiversityiscreatedwithincertain56.Arosecanbecrossedwithadifferentkindofrosebutarosewillnevercrosswithapotato.Geneticengineering57usuallyinvolvestakinggenesfromonespeciesandinsertingthemintoanotherinanattempttotransferadesiredcharacteristic.Thiscouldmeanforexampleselectingagenewhichleadstotheproductionofachemicalwithanti-freeze58fromanarticfishandinsertingitintoapotatoorstrawberrytomakeitfrostresistantinessencethenbiotechnologyallowshumansto59thegeneticwallsthatseparatespecies.Justlikethegreenrevolution60somecallthegenerevolutioncontributestotheproblemofgeneticuniformity-somesayevenmoreso61geneticistscanemploytechniquessuchascloningand62culture培养andprocessesthatproduceperfectly63copies.Concernsabouttheerosionofbiodiversitythereforeremain.Geneticallyalteredplantshoweverraisenew64suchastheeffectsthattheymayhaveonusandtheenvironment.Wearetlyingblindlyintoaneweraofagriculturalbiotechnologywithhighhopesfewconstraintsandlittleideaofthepotential65saidsciencewriterJeremyRifkin.
Theydecidedtoabandonthesavingplanafterdiscussion.
Wecangetinadequatemoneyforournewproject.
Inrecentyearsanewfarmingrevolutionhasbegunonethatinvolvesthemanipulationoflifeatafundamentallevel—thegene.Thestudyofgeneticshas51anewindustrycalledbiotcehnology.Asthenamesuggestsit52biologyandmoderntechnologythroughsuchtechniquesasgeneticengineering.Someofthenewbiotechcompaniesspecializeinagricultureandareworkingfeverishlyto53seedsthatgiveahighyieldthat54diseasesdroughtandfrostandthatreducetheneedforhazardouschemicalsIfsuchgoalscouldbeachieveditwouldbemost55.Butsomehaveraisedconcernsaboutgeneticallyengineeredcrops.Innaturegeneticdiversityiscreatedwithincertain56.Arosecanbecrossedwithadifferentkindofrosebutarosewillnevercrosswithapotato.Geneticengineering57usuallyinvolvestakinggenesfromonespeciesandinsertingthemintoanotherinanattempttotransferadesiredcharacteristic.Thiscouldmeanforexampleselectingagenewhichleadstotheproductionofachemicalwithanti-freeze58fromanarticfishandinsertingitintoapotatoorstrawberrytomakeitfrostresistantinessencethenbiotechnologyallowshumansto59thegeneticwallsthatseparatespecies.Justlikethegreenrevolution60somecallthegenerevolutioncontributestotheproblemofgeneticuniformity-somesayevenmoreso61geneticistscanemploytechniquessuchascloningand62culture培养andprocessesthatproduceperfectly63copies.Concernsabouttheerosionofbiodiversitythereforeremain.Geneticallyalteredplantshoweverraisenew64suchastheeffectsthattheymayhaveonusandtheenvironment.Wearetlyingblindlyintoaneweraofagriculturalbiotechnologywithhighhopesfewconstraintsandlittleideaofthepotential65saidsciencewriterJeremyRifkin.
Don’tTreatAnimalsasFurryTest-tubesMostofusagreethatthereisamoralobligationtominimizethesufferingofanycaptiveanimals.Inadditiontherearenumerousself-servingreasonswhyweshouldrespectthewelfareofourcaptivecompanions.Howevertheimpactofpooranimalwelfareonthequalityofanimalsciencealwaysconcernsascientistthemost.Rodents灵长类动物makeupover80%oftheanimalsusedinscientificproceduresandmostarekeptinsmallbarrencages.Suchhousingisknowntoconstrainnormaldevelopmentaffectingthestructureandfunctionofadultrodentbrains.Theserodentsmayspend50%ofwakinghoursperformingrepetitiveactivitieswithoutapparentpurpose.Thisabnormalbehaviorislikelytoreflectwhatisgoingoninsidethebody.AsethnologistHannoWfirbeloftheJustusLiebigUniversityofGiessenGermanyputsitThepointthattheenvironmentmightchangebehaviorbutitdoesn’tchangebiologyisridiculous.Everybehaviorhasaphysiologicalbackground.Ifwelfareaffectsbehaviorandthereforebiologyitwillaffectscientificoutcomes.Aslongaswecontinuetotreatexperimentalanimalsassimplefurrytest-tubesignoringtheirabilitiesandneedsweendangerthequalityoftheworkwedowiththem.SohowcanweimprovelifeforotherspecieswhenwecannotexperienceitastheydoWe’dbetterasktheanimals.Askthemwhattheyneedandwhatcausesthemsufferingthroughcarefullydesignedpreferencetestsandin-depthbehaviouralresearch.Scientistshavealreadybegunthistaskandhavebeentoldsomeimportantandunexpectedfactsbytheirstudysubjects.Byconsistentlyself-medicatingwithpainkillersbroilerchickens嫩鸡havetoldusthattheyareinchronicpain.Bymovingabarriertwicetheirsizemink水貂havetoldusthatwaterbathsarethemostimportantenrichmentforthem.Byonlystoppingtheirfruitlessstereotypicdiggingincertaincircumstancesgerbils沙鼠havetoldusthattheyneedtobeabletosleepintunnelednest-boxes.Bybehavingnormallyagainstarlingshavetoldusthattheyneedhighfrequencylightbulbs.Whatistheauthor’sattitudetowardsthewaymostexperimentalanimalsaretreated
Intelligentcardoorclampsupwhendanger’saboutAccidentscausedbycardoorsbeingopenedintothepathofoncomingvehiclesorcyclistsarecommonincities.Buttheseincidentscouldbecomeathingofthepastifdoorsthatreacttopotentialimpactscatchon.ThecreativeideaofMichaelGrafatBMWandMichaelStrolz’steamattheTechnicalUniversityofMunichthehaptic-technologythatgivestactilefeedback-doorscouldcutbothroadinjuriesandrepairbillstheysay.Thecurrentprototypelookslikeanormalcardoorbutanextrametalbarrunsthroughitscentreandconnectstothecar’sframebetweenthehinges.Innormalmodethebarmovesfreelyanddoesn’taffectthedoor’smovement.Howeverifsensorsdetectanearbyobstacleatthesametimeasanaccelerometerdetectsanattempttoopenthedoorthedoor’sswingisrestrictedbyalinearmotorattachedtothebar.Topassonmoreinformationtotheusertheamountofdoorresistanceisinproportiontotheproximityofanobject-forexampleyoumightswingadoorhalfwayopenwithoutproblemsbeforeitgetsstifferasitnearsalamppost.Thecurrentprototypeusessupersonicsensorstospotdangersbutbecausetheyhavealimitedfieldofviewthenextversionwillusecamerasthatcanspan180°saysStrolz.Thenwewillbeabletosensethecompleteworkspaceofthedooranddetectpeoplewalkingbythecarorcyclingtowardsithesays.Reactionsfrom16volunteerswhotriedthenewdooratBMW’sMunichresearchcentrehavebeenencouragingtheteamtoldarecentconferenceonhapticsinSaltLakeCityUtah.ThetechnologyismatureenoughthatacarfactorycouldbepumpingitoutincarswithinayearsaysStrolz.Thebasicmechanismislikeonealreadyfeaturedinsomecars-forexampletaxiswithautomaticpassengerdoors.HoweverBMWisyettomakeanydecisiononwhethertorollitout.HowdidthevolunteerswhotriedthenewdooratBMWrespondtoit
2.SpaceJunkCosmos2251wasanordinarysatellitedesignedtotransmitsignalsacrossthevastRussianlandmass.Launchedin1993itwouldappearevery90minutesorsooverthenorthernskiesrelayelectronicblipsofinformationamonganetworkofsatellitesandgroundstationslikeahockeyplayerpassingthepuckanddisappearoverthesouthernhorizon.Iridium33launchedforMotorolain1997didsomethingsimilarthoughittookaslightlydifferentorbitthatbroughtitclosesttoEarthduringitspassoverNorthAmerica.Foryearsthetwosatellitescircledtheplanetmindingtheirownbusinessnevercomingwithinathousandkilometersofoneanother.ThensomethinghappenedtoCosmos.Itmayhavesprungasmallleak;perhapsitstruckatinyasteroidorapieceofdebris.NobodyknowsforsurebutforonereasonoranotherCosmosdriftedoffcourse.T.S.KelsoanaeronauticsexpertatAnalyticalGraphicswhichprovidessatellite-trackingservicestoNASAnoticedthattheorbitsofCosmosandIridiumwerebringingthetwosatellitesclosertoeachotherallthetime.InFebruaryheissuedawarningthattheywouldpasswithinakilometerofoneanothertiewasright.OnFeb.10MotorolalosttrackofIridium’ssignal.OverthenextfewdaysKelsoandotherssurmisedthatwhatmanyhadfearedforyearshadfinallycometopass:twointactsatelliteshadcollidedheadon.Theconsequencesgofarbeyondmerelythelossoftwopiecesofproperty.Eachsatelliteweighedmorethanhalfametrictonandwasmovingat7.5kilometerspersecond.Theresultingexplosionwascatastrophicgeneratingamassivecloudofcosmicdebris—perhapsl00000piecesofjunkbiggerthanonecentimeterindiameterestimatesDavidWrightaspaceexpertattheUnionofConcernedScientists.Inonestroketheaccidentincreasedbynearlyathirdthenumberofstrayobjectsinthecrucial700-to-900-kilometerhandknownaslowEarthorbitLEO.Thejunkcloudwilleventuallydispersearoundtheentireplanetlikeashroud.Theeventservedasawake-upcalltospaceplanners.Insuranceratesforthe$18billionworthofactivecommercialsatellitesnowinorbithavetickedupwardsby10to20percentsincetheaccident.Governmentstoohavegrowntorelyonnetworksofsatellitestogatherintelligencedirectweaponssystemsforecastclimateandweatherchangesmonitoragricultureandoperatecommunicationsandnavigationsystems.Expertscalculatethatdebriswillnowstrikeoneofthe900activesatellitesinLEOeverytwoorthreeyears.Forthefirsttimejunkisthesinglebiggestriskfactortoequipmentinsomeorbits.AmongtheorbitalthreatsaretwoformerSovietnuclearreactors.EventheInternationalSpaceStationmayonedaybeatriskasdebrisslowlydescendstoits350-kilometerorbit.Thejunkcloudwillmainlydisperseinthe700-to-900-kilometerbandknownasLEO.
Thelectureissodullthathecan'tfocushisattentiononit
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