summary例子和问题详解.docx

summary例子和问题详解.docx

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summary例子和问题详解

TheDevelopmentofWriting

Fewpeoplewoulddisagreewiththebeliefthatprimitivemanlearnedtospeaklongbeforehedevelopedasystemofwriting.Butwhilehisearlyspokenlanguagemayhavebeennothingmorethanafewsounds,earlymancouldtransmitmessagesacrossdistancesbymeansofsignalsfromdrums,smokeandfire.Itwasprobablyadesiretorecordmessagesthatledtothedevelopmentofalphabets.Forearlyman,whocouldspeakandwhocouldsendmessages,couldnotputthosemessagesintopermanentform.Thedesiretohavepermanentrecordsmaynotbeeasilyunderstoodintoday’sworldwhereelectronicsciencehasmadediskandtaperecordingscommonplace.Ifearlymanwantedtoleaverecordsofpasteventstoremindhimofgoodtimesandbad,hehadtodependonhismemory,andonprimitivemarkingssuchaspilesofstones,cuttingsonsticks,etc.Thelimitationsofthissystemledearlymantoturntorockdrawingsfortheexpressionofsophisticatedideas.Thisformofwritingdependedonpicturestoconveyideas,andalthoughmoreadvancedthanpreviousdevelopments,itwasstilltoolimitedformantobeentirelysatisfied.Manfinallywasabletodevelopasystemofpicturewritingthatassociatedsymbolsandsound.Thissystem,whichwasoriginatedbytheearlySumeriansandtheEgyptiansmorethan3,000B.C.,isbasedonthesameprinciplethatwesuetodayinmostworldalphabets.Itwasabout1,000B.C.thatthePhoenicianstookthecomplicatedpicturealphabetsoftheEgyptiansandsimplifiedthenintoabout30symbols,eachonestandingforaconsonantsound.Finally,theancientGreeks,about800B.C.,refinedthisPhoenicianalphabetandaddedsignsforvowelsounds.ThealphabetusedinEnglish,andinmanyotherworldlanguages,iscalledtheRomanalphabetbecauseitwasdevelopedbytheRomanswhohadtakenmostofitfromanotherItalicpeople,theEtruscan,who,intheirturn,hadlearneditfromtheancientGreeks.LettersonancientmonumentsinRomeprovethattheRomanalphabet,thesamealphabetusedtoday,hadbeenperfectedbyA.D.114.

SecrettoLongevityLiesinGenes,StudyFinds

TueJun11,5:

16PMET

byMaggieFox,HealthandSciencesCorrespondent

WASHINGTON（Reuters）Wanttolivetobe100?

Pickoldgrandparents.It’sanoldirony,butresearcherssaidonTuesdaytheyhadshownthisisremarkablytruewhenitcomestosurvivingintooldage,andtheybelieveaclusterofjustafewgenesmayberesponsible.Theyhavesetupacompanythatstudiescentenarianstoseeifthegenericsecrettolivingalongandhealthylifemayresultindrugsthatcanpreventthediseasesofaging,suchasAlzheimer’sandheartdisease."Itisn’treallythatobvious,"Dr.ThomasPerls,wholedthestudy,saidinatelephoneinterview."Itisn’toldagethatrunsinfamilies.It’sexceptionaloldagethatrunsinfamilies.Wethinkthismaybeahandfulofgenesthatcouldbeplayingreallysubstantialrolesintheabilitytogettoveryoldage,muchofitingoodhealth."

Perl’steamatHarvardUniversityandBethIsraelDeaconessMedicalSchoolstudied444families,includingmorethan2,000relativesofpeoplewholiveto100.DemographerJohnWilmothoftheUniversityofCaliforniaBerkeleycomparedthisdatatothe1900censusandtheSocialSecurityAdministrationdatabase."Femalesiblingshaddeathratesatallagesataboutone-halfthenationallevel,"theywroteintheirreport,publishedinthisweekissueoftheProceedingsoftheNationalAcademyofSciences."Malesiblingsofcentenarianswereatleast17timesaslikelytoattainage100themselves,whilefemalesiblingswereatleasteighttimesaslikely."Perlsisnotinterestedinextendinglifeatanycost.

WHOWANTSTOGETTHATOLD,ANYWAY?

"Peoplemightthink,whowantstoliveto100anyway?

becausepeoplegettheideathattheolderyouget,thesickeryouget."Buthisstudyfoundjusttheopposite."YoucangetAlzheimer,stroke,cancerinyour60sand70sandexpecttoliveanother30,40years."EarlierworkhasshownmanyofthesepeoplesharesimilaritiesintheirDNA,especiallyonchromosome4.Perlshopeshiscompany,Centagenetix（http:

/.centagenetix.）canhomeinontheimportantgenesandperhapsmakediscoveriesthatwillleadtodrugsthatcanstaveoffdisease.

"Discoveringthesegeneswillleadtounderstandingthebiochemicalpathwaysthatthosegenesaffect,"hesaid."Myhopeisthatthatwouldhelpalotofotherpeopleagemoreslowlyanddelayand,mygoodnessevenescape,somethinglikeAlzheimer."

Whichgenesyoudonothavemaybeasimportantasthoseyoudo,Perlssaid.Forinstance,hefoundthe100-year-oldswereveryunlikelytohaveaversionofagenecalledAPOE-4,whichisassociatedwithhighcholesterolandAlzheimer.Environmentdidnotseemtobetooimportanttothosewholivedtobe100.CensusBureaudatashowedtheyweremorelikelytobepoorandpoorlyeducated?

somethingnotusuallyassociatedwitholdage.

Butformostofus,environmentandbehavioriskey."Ithinktheaveragesetofgenesgetsustoourmid-tolate-80s,"saidPerls,ageriatricianwhonowworksatBostonMedicalCenter."IbasethisontwinstudiesandonSeventhDayAdventists,whohavealifeexpectancyof87years,whodoeverythingright。

Theysmoke,theyarelean,theyarevegetarian,theyexerciseandasaresulttheylive10yearslongerthantherestofus.Thatbasicallytellsuswhatourgenesarecapableof.Buttolivetheextra15,20yearsbeyondthat,Isuspectgenesareplayingagreaterrole."

SoThatNobodyHasToGoToSchoolIfTheyDon'tWant

byTobyRogerSipher

AdeclineinstandardizedtestscoresisbutthemostrecentindicatorthatAmericaneducationisintrouble.

Onereasonforthecrisisisthatpresentmandatory-attendancelawsforcemanytoattendschoolwhohavenowishtobethere.SuchchildrenhavelittledesiretolearnandaresoantagonistictoschoolthatneithertheynormorehighlymotivatedstudentsreceivethequalityeducationthatisthebirthrightofeveryAmerican.

Thesolutiontothisproblemissimple:

Abolishcompulsory-attendancelawsandallowonlythosewhoarecommittedtogettinganeducationtoattend.

Thiswillnotendpubliceducation.Contrarytoconventionalbelief,legislatorsenactedcompulsory-attendancelawstolegalizewhatalreadyexisted.WilliamLandesandLewisSolomon,economists,foundlittleevidencethatmandatory-attendancelawsincreasedthenumberofchildreninschool.Theyfound,too,thatschoolsystemshavenevereffectivelyenforcedsuchlaws,usuallybecauseoftheexpenseinvolved.

Thereisnocontradictionbetweentheassertionthatcompulsoryattendancehashadlittleeffectonthenumberofchildrenattendingschoolandtheargumentthatrepealwouldbeapositivesteptowardimprovingeducation.Mostparentswantahighschooleducationfortheirchildren.Unfortunately,compulsoryattendancehamperstheabilityofpublicschoolofficialstoenforcelegitimateeducationalanddisciplinarypoliciesandtherebymaketheeducationagoodone.

Privateschoolshavenosuchproblem.Theycanfailordismissstudents,knowingsuchstudentscanattendpublicschool.Withoutcompulsoryattendance,publicschoolswouldbefreertoouststudentswhoseacademicorpersonalbehaviorunderminestheeducationalmissionoftheinstitution.

Hasnotthenobleexperimentofaformaleducationforeveryonefailed?

Whilewepayhomagetothehomily,"Youcanleadahorsetowaterbutyoucan'tmakehimdrink,"wehavepretendeditisnottrueineducation.

Askhighschoolteachersifrecalcitrantstudentslearnanythingofvalue.Askteachersifthesestudentsdoanyhomework.Quitethecontrary,thesestudentsknowtheywillbepassedfromgradetogradeuntiltheyareoldenoughtoquitoruntil,asismorelikely,theyreceiveahighschooldiploma.Atthepointwhenstudentscouldlegallyquit,mostchoosetoremainsincetheyknowtheyarelikelytobeallowedtograduatewhethertheydoacceptableworkornot.

Abolitionofarchaicattendancelawswouldproduceenormousdividends.

First,itwouldalerteveryonethatschoolisaseriousplacewhereonegoestolearn.Schoolsareneitherday-carecentersnorindoorstreetcorners.Youngpeoplewhoresistlearningshouldstayaway;indeed,anendtocompulsoryschoolingwouldrequirethemtostayaway.

Second,studentsopposedtolearningwouldnotbeabletopollutetheeducationalatmosphereforthosewhowanttolearn.Teacherscouldstoppolicingrecalcitrantstudentsandstarteducating.

Third,gradeswouldshowwhattheyaresupposedto:

howwellastudentislearning.Parentscouldagainreadreportcardsandknowiftheirchildrenweremakingprogress.

Fourth,publicesteemforschoolswouldincrease.PeoplewouldstopregardingthemaswaystationsforadolescentsandstartthinkingofthemasinstitutionsforeducatingAmerica'syouth.

Fifth,elementaryschoolswouldchangebecausestudentswouldfindoutearlytheyhadbetterlearnsomethingorriskflunkingoutlater.Elementaryteacherswouldnolongerhavetopasstheirfailuresontojuniorhighandhighschool.

Sixth,thecostofenforcingcompulsoryeducationwouldbeeliminated.Despiteenforcementefforts,nearly15percentoftheschool-agechildreninourlargestcitiesarealmostpermanentlyabsentfromschool.

Communitiescouldusethesesavingstosupportinstitutionstodealwithyoungpeoplenotinschool.If,inthelongrun,theseinstitutionsprovemorecostly,atleastwewouldnotconfusetheirmissionwiththatofschools.

Schoolsshouldbeforeducation.Atpresent,theyareonlytangentiallyso.Theyhaveattemptedtoserveanall-encompassingsocialfunction,tryingtobeallthingstoallpeople.Inthepr