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Polygenicinheritanceisusedtorefertotheinheritanceofquantitativetraits,traitswhichareinfluencedbymultiple
genes,notjustone.Inadditiontoinvolvingmultiplegenes,polygenicinheritancealsolooksattheroleofenvironment
insomeone'sdevelopment.Oneeasilyunderstoodexampleofpolygenicinheritanceisheight.Peoplearenotjustshort
or tall; they have a variety of heights which run along a spectrum. Furthermore, height is also influenced by
environment; someonebornwith tall genes could become shortdue tomalnutrition or illness, for example,while
someonebornwithshortgenescouldbecometallthroughgenetictherapy
SolarPanels:basicelement puresilicon;Whensiliconisstrippedofallimpurities,itmakesaidealneutralplatformfor
thetransmissionofelectrons;Solarpanelsarecreatedbycombiningsiliconwithotherelementsthatdohavepositive
ornegativechargeseg:P;Whenthenegativeplatesofsolarcellsarepointedataproperangletothesun,photons
bombardthesilicon/phosphorusatoms.Eventually,the9thelectron,whichwantstobefreeanyway,isknockedoffthe
outerring.Thiselectrondoesn'tremainfreeforlong,sincethepositivesilicon/boronplatedrawsitintotheopenspot
onitsownouterband.Asthesun'sphotonsbreakoffmoreelectrons,electricityisgenerated.
Nitrile gloves are a type of disposable glove made of synthetic rubber. They contain no latex proteins and offer
excellentresistancetowearandtears.
Nitrileglovesaremorepunctureresistantthanmanyothertypesofrubberglovesandcanbeusedtooffersuperiorresistance
to
many
types
of
chemicals.
oftenconsideredtobeoneofthethestrongesttypesofdisposablegloveandaregenerallysafeforpeoplewhoareallergictolatex.
popularfortheirhighdegreeofflexibilityandsuperiorsolventresistance. resistanttomanyoils&someacids=>makesagoodchoiceformanymanufacturingenvironments. usedintheemergencymedicalservicefields,suchasbyparamedics.Cybernetictheoryhasfourcomponents:variety,circularity,processandobservation.
Varietyrelatestotheinformationandcommunication/controltheoriesandemphasizeschoices. Circularityignoresconceptsofhierarchyinsystems,favoringamorelevelplayingfield. Processlooksatfeedbackloopsandinvolvesregulationswithinsystems. Observationinvolvesdecisionmakingandhowwecomputeconclusions.DNAfingerprintingisawayofidentifyingaspecificindividual;alsoknownasgeneticfingerprintingorDNAprofiling
usedbothforidentifyingpaternityormaternityandforidentifyingcriminalsorvictims. discussionofusingitasasortofpersonalidentifieraswell,althoughviabilityofthisisdebatable. DNAfingerprintingusesaspecifictypeofDNAsequence,knownasamicrosatellite,tomake identificationmuch
easier.
Microsatellites are short pieces of DNA which repeat many times in a given person's DNA. In a given area,microsatellites
tend
to
be
highly
variable,
making
them
ideal
for
DNA
fingerprinting.
By
comparing
anumber
of
microsatellitesinagivenarea,onecanidentifyapersonrelativelyeasily.
sections of DNA used in DNA fingerprinting, although highly variable, are passed down from parents to theirchildren
usefulinthecaseofidentifyingvictimsbecauseevenincaseswherethebodymaybedisfiguredpastidentification,andteethorotheridentifyingfeaturesmaybedestroyed,allittakesisasinglecellforpositiveidentification
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Stemcellresearch
is a relatively new technology that takes primitive human cells and develops them intomost any of the 220varietiesofcellsinthehumanbody,includingbloodcellsandbraincells.
Somescientistsandresearchershavegreathopeforthisresearchanditsabilitytouncovertreatmentsandpossiblyevencuresforsomeoftheworstdiseases includingheartdisease,diabetes,andneurodegenerativediseases like
Alzheimer'sandParkinson's.
givesrisetofearofhumancloningandseriousconcernsovertheethicsofconductingscientificresearchon,whichincludesthedestructionof,humanembryos.
Types:Humanstemcellsprimarilycomefromembryosoradulttissue.Embryonicstemcellscanbecreatedsolelyforthepurposeofstemcellresearchortheycanbetheleftoverfromotherprocesses,suchasfromIVF.
Adultstemcellscanbeharvested fromadult tissuewithminor, ifany,harm to theadult.Embryonicstemcells,however,aresaidtobegenerallyeasiertoextractthantheadultstemcells,andembryonicstemcellsaresaidto
havemoreusesthantheiradultcounterparts.
Plasmonics
Plasmons are density waves of electrons, created when light hits the surface of a metal under precisecircumstances.
These
density
waves
are
generated
at
optical
frequencies,
and
are
very
small
and
rapid.
They
can
theoretically encode a lot of information,more thanwhat's possible for conventional electronics. Plamonics is
thoughttoembodythestrongestpointsofbothopticalandelectronicdatatransfer,allowingthefasttransmission
ofinformationoververysmallwires.
Plasmonics,sometimescalled"lightonawire,"wouldallowthetransmissionofdataatopticalfrequenciesalongthesurfaceofatinymetalwire,despitethefactthatthedatatravelsintheformofelectrondensitydistributions
ratherthanphotons.
main limitationtoplasmonicstoday isthatplasmonstendtodissipateafteronlyafewmillimeters,makingthemtooshortlivedtoserveasabasisforcomputerchips
Forsendingdataoverlongerdistances,techneedsimprovement needmaterialwithalowrefractiveindex,ideallynegative.
no
natural
material
with
ve;
so
nanostructured
materials
must
be
used
to
fabricate
effective
plasmonic
devices.hence,plasmonicsisfrequentlyassociatedwithnanotech
Plasmonicwiresmayactashighbandwidthfreewaysacrossthebusiestareasofthesiliconchip used in biosensors: When a particular protein or DNA molecule rests on the surface of a plasmoncarrying
metallicmaterial,itleavesitscharacteristicsignatureintheangleatwhichitreflectstheenergy.
Carbonfiber
isthecommonnameusedtorefertoplastic(typicallyepoxy)reinforcedbyagraphitetextile. isknownalternativelyascarbonfiberreinforcedplasticorcarbonfibercomposite. Expensivebuthighweighttostrengthratio;verydifficulttobreak; Introducingcarbonnanotubes into the fiber iscurrently in researchstages,andmayoffer improved ratiosof10
timesorgreateraspaceagematerial
employedinhighqualitycars,boats,bicycles,andplanes,includingpopularFormulaOneracecars. oldbridgesmaybesparedfromdestructionandrebuildingthroughsimplecarbonfiberreinforcements,whichare
comparativelycheaper.
Gforcereferstoeithertheforceofgravityonaparticularcelestialbodyortheforceofaccelerationanywhere.Gforce
ismeasureding'swhere1g=9.8m/s2
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Magnetron: Typicallyusedinmicrowaveovens,amagnetronisatubethatutilizeselectricalandmagneticcurrentsin
ordertocreateanintenseheatoutput.
Wormholeisahypotheticalspacetimetopology,a"shortcut"thatwouldallowtravelbetweentwopointsatapparently
fasterthanlightspeeds.Inreality,movementthroughawormholewouldnotbefasterthanlight,butrathermovingat
normalspeedthroughfoldedspace.
Kevlarisanextremelystrongmaterialthatderivesitsstrengthfromitsweave.Itiswovenliketinyspiderwebs.islight,
itis
the
premium
choice
for
bulletproof
vests.
use
in
shelters
for
protection
against
tornadoes.
can
deflect
large
materialsatspeedsofupto250mph
Compositematerials for construction, engineering, andother similar applications are formedby combining twoor
morematerials insuchawaythattheconstituentsofthecompositematerialsarestilldistinguishable,andnot fully
blended.Eg:concrete;usetwoconstituents:abinderormatrixandareinforcement
GenomicDNA
is the DNA that holds the complete set of genetic data for an organism. spans 46 chromosomes; providing acompletesetofgeneticinformationincludingcodingDNAwhichleadstotheexpressionofgenetictraits,andnon
codingDNA
which
does
not
have
this
function.
The genomic DNA of humans has been sequenced as part of the Human Genome Project, with the goal ofeventuallylearningaboutthespecificfunctionsofvariousareasofthegenome.
Beingabletolocatespecificgenesandotherinformationcouldbeusefulfordiagnosisandeventualtreatmentofgeneticconditions.
AgeostationaryorbitisoneinwhichthespeedatwhichasatelliteorbitstheEarthcoincideswiththespeedthatthe
Earthturnsandatthesamelatitude,specificallyzero,thelatitudeoftheequator.Geostationaryobjectsinorbitmust
beatacertaindistanceabovetheEarthtoremaininthesamepositionrelativetotheEarth'ssurface.
Since
the
only
geostationary
orbit
for
the
Earth
is
in
a
plane
with
the
equator
at
35,786
kilometers,
there
is
only
one
circlearoundtheworldwheretheseconditionsoccur.Thismeansthatgeostationary'realestate'isfinite.
Ageosynchronous orbitisoneinwhichthesatelliteissynchronizedwiththeEarth'srotation,buttheorbitistiltedwith
respecttotheplaneoftheequator.Asatelliteinageosynchronousorbitwillwanderupanddowninlatitude,although
itwillstayoverthesamelineoflongitude.geostationaryorbitisasubsetofallpossiblegeosynchronousorbits.
LowearthorbitisonlyslightlyabovetheEarth,byouterspacestandards,200 2000km(124 1240miles)inaltitude.
Below 124 miles, orbits rapidly degrade, causing surface impact, and above 1,240miles or even less, the Earth's
radiationbeltsdamageelectronicequipment,necessitatingspecialshielding.Theregion from1,243milesaltitudeto
geostationaryorbitisknownasMediumEarthOrbit.Lowearthorbit,mediumearthorbit,andgeostationaryorbitare
knownas
LEO,
MEO,
and
GSO
respectively.
Eg:
International
Space
Station,
fluctuates
between
320
km
and
347
km
abovethesurface.makingabout17orbitsperday;MostproposalsforspacehotelsareplacedinLEO
Humoralimmunityisatypeofimmunitywhichisconferredthroughthereleaseofantibodieswhichareusedtotarget
cells fordestructionby thebodywhen these cells are viewed aspotentiallydangerous.This typeof immunity is a
complementtocellularimmunity,inwhichcellsreleasetoxinstokillunwantedinvaders,orattacktheinvadersdirectly
tokillthem.
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CentralDogmaofmolecularbiology
isthatinformationinbiologicalsystemsonlyflowsinonedirection:fromDNAtoRNAtoproteins
DNA istranscribedtoRNAwhich istranslatedtoprotein.Protein isneverbacktranslatedtoRNAorDNA;andexcept
forretroviruses,DNAisnevercreatedfromRNA.Furthermore,DNAisneverdirectlytranslatedtoprotein.
DNA isthe longtermhardcopyofthegeneticmaterial;bywayofanalogyitissimilartoinformationstoredonacomputer'sharddiskdrive.DNAisverystableandinert
RNA is a temporary intermediary betweenDNA and the proteinmaking factories, theribosomes.RNAcouldbecompared to informationstored inacache. It isunstableand
lackssecondarystructure.SomeRNAhasenzymaticactivity.
Proteinscouldbeviewedastheprogramsofthecell(tocompleteouranalogy).Theyarethephysicalrepresentationoftheabstractinformationcontainedwithinthegenome.Proteinsvarygreatlyintheir
activityandhalflife.proteinstheycome inallshapesandsizes.Forexample,collagen isaubiquitousproteinthat
makesupalmostallofyourbodiesmainstructuraltissue
Geneticdrift
isamechanismofevolutionthatoccursbyrandomchanceratherthannaturalselection. Ingeneticdrift,apopulationexperiencesachange in the frequencyofagivenallele,promptedby random luck
ratherthananeedforadaptation.Thisdiffersfromnaturalselection,inwhichallelicfrequencyisalteredbasedon
thefittestgenessurvivingtoreproduceandtheweakergenesdyingoff.
Geneticdrifttendstobeaphenomenonamongstsmallerpopulations,whilenaturalselectionholdsswayinlargerpopulations.
Bioavailability isa termusedby severalbranchesofscientificstudy todescribe thewaychemicalsareabsorbedby
humansand
other
animals.
A
bioavailability
measurement
of
amedication,
when
it
reaches
circulation
in
the
body,
describesaspectslikeabsorbencyandhalflife.Itcanevaluatemedicationdeliveryaswell.
Atransgenicorganismisanorganismwhichhasbeenmodifiedwithgeneticmaterialfromanotherspecies.Thegenetic
modificationisaccomplishedbyinsertingDNAintoanembryowiththeassistanceofavirus,aplasmid,oragenegun.
Theembryo isallowed todevelop,and thematureorganismwillexpress theDNAwhichhasbeen inserted into its
genome. Transgenic organisms can also pass the modification on to future generations by breeding with other
membersofthesamespecies.Uses:developmentofgeneticallymodifiedcrops;sometimesarerenderedsterilesothat
theycannotinterbreed,forthepurposeofprotectingpatentsandtopreventtransgenicorganismsfromcrossbreeding
withwild relatives;used in scientific research eg transgenicmice;Mice can bemodifiedwith humanDNA for the
purposeoftestingmedicaltreatmentsandseeinghowtheymightbehaveinahuman.
StringTheory,sometimescalledtheTheoryofEverything, isthoughtbysometobetheunifyingfieldtheoryEinstein
sought before his death. String theory is the first mathematically sound theory that reconciles the world of the
infinitesimallysmall,withtheworldweknowatlarge.ItunitesEinsteinsTheoryofRelativitywithquantumphysicsand
offersapotentialexplanationfortheBigBang.thestrengthofstringtheoryisthatitaccountsforallfourknownforces
in one elegant theory. These fundamental forces are gravity; the strong and weak nuclear forces; and
electromagnetism.
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Bioleaching
usesbacterialmicroorganisms toextractpreciousmetals,suchasgold, fromore inwhich it isembedded.Asanalternativetosmeltingorroasting,minersusebioleachingwhentherearelowerconcentrationsofmetalinoreand
theyneedanefficient,environmentallyresponsiblemethod.Thebacteriafeedsonnutrients inminerals,thereby
separatingthemetalthatleavestheorganism'ssystem;thenthemetalcanbecollectedinasolution.
usedtorecovercopper,zinc,lead,arsenic,antimony,nickel,molybdenum,gold,silver,andcobalt. Bioleachingcaninvolvenumerousferrousironandsulfuroxidizingbacteria,includingAcidithiobacillusferrooxidans
andAcidithiobacillus(formerlyknownasThiobacillus).
Asageneralprinciple,Fe3+ionsareusedtooxidizetheore.Thisstepisentirelyindependentofmicrobes.Theroleof thebacteria is the furtheroxidationof theore,butmore importantly also the regenerationof the chemical
oxidantFe3+fromFe2+
Experiments have shown that two fungal strains (Aspergillus niger, Penicillium simplicissimum) were able tomobilizeCuandSnby65%,andAl,Ni,Pb,andZnbymorethan95%.
Ads:Economical (simplerand therefore cheaper tooperate),Envirofriendly > lessemissions andhencehigherprofitbydecreasingcostofabatement
Disads:process isveryslowcompared tosmelting> lessprofits;Toxicchemicalsaresometimesproduced in theprocess.
Sulfuric
acid
and
H+
ions
which
have
been
formed
can
leak
into
the
ground
turning
it
acidic
Magneticstorm,
alsoknownasageomagneticstorm,isadisturbanceintheEarth'smagneticfieldcausedbycoronalmassejections(CMEs)orsolarflaresfromtheSun.
Amagneticstormusuallybeginsbetween24and36hoursafterthesolarevent,whenashockwaveofsolarwindreachestheEarth'sionosphere.thentypicallylasts24to48hours,thoughsomemaylastaslongasdays.
Theeffectsofamagnetic storm includedisruptionof communicationsandnavigation systems, intenseauroras,damagetosatellites,andduringthemostextremestorms,inducedcurrentsinpowerlinesandpipelinesthatresult
inpoweroutagesandcorrosion.
RecombinantDNA(rDNA)
is a type ofDNA that is artificially created by inserting a strand ormore ofDNA into a different set of DNA.RecombinantDNA isused ingeneticmodificationtocreatecompletelyneworganismsbyaddingartificialbitsor
bitsofDNAfromotherorganismstoanexistingcreature.
usedtointroduceveryspecificfeaturesintocrops,bacteria,andanimals,usuallytomakethemmorebeneficialtohumans,althoughsometimessimplyasademonstrationofatechnique,orsometimesasanartisticstatement.
uses :tomakecropsdroughtresistant,tocreatenewvaccines,suchas thenewestHepatitisBvaccine,tomakecropsnaturallypestresistant,andtheinfamousGloFish,whichwerezebrafishthatweremadefluorescent.
DifferentTypesofRecombinantDNATechnology
1. bacterialtransformation it involvesencouragingaspeciallypreparedbacterialcellto take inapieceof foreignDNA and incorporate itdirectly into thebacterial genome.E. coli areoftenused as thehosts for thismethod,
becausetheyareeasytogrowandreproducequickly.
2. Nonbacterialtransformation almost identicaltobacterialtransformation,except thatbacteriaarenotusedashostcells.iscommonlyusedineukaryoticcells,likeyeastorplantcells.Thistypeoftransformationcanbedoneby
shootingDNAfragmentsattachedtotinypelletsdirectly intocellnuclei,orby injectingDNA intocellnucleiwith
microscopicneedles
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3. phage introduction,which involvesusingspecific typesofviruses,calledphages, to inject foreignDNA intohostcells. Viruses can carry either singlestranded or doublestrandedDNA, so they can be used to replace single
strandedDNAatspecificlocations.
Nanorobotsaretheoreticalmicroscopicdevicesmeasuredonthescaleofnanometers.
Nanomedicine'snanorobotsaresotinythattheycaneasilytraversethehumanbody.Scientistsreporttheexteriorofananorobotwilllikelybeconstructedofcarbonatomsinadiamondoidstructurebecauseofitsinertproperties
andstrength.
Super
smooth
surfaces
will
lessen
the
likelihood
of
triggering
the
body's
immune
system,
allowing
the
nanorobotstogoabouttheirbusinessunimpeded.Glucoseornaturalbodysugarsandoxygenmightbeasource
forpropulsion,andthenanorobotwillhaveotherbiochemicalormolecularpartsdependingonitstask.
Molecularnanotechnology (MNT), theumbrellascienceofnanomedicine,envisionsnanorobotsmanufactured innanofactoriesnolargerthantheaveragedesktopprinter.Thenanofactorieswouldusenanoscaletoolscapableof
constructingnanorobotstoexactingspecifications.
Biological magnification, or biomagnifications/bioamplification, explains why a substance appears in higher
concentrations inorganismshigher inagiven foodchain than inorganisms lower ina foodchain.Thishappenscoz
creatureshighupinthefoodchainfeedoncreaturesthatarelowerinthefoodchainandabsorbthesubstancesfrom
theorganisms
they
consume
in
addition
to
the
substances
they
directly
absorb
from
the
environment.
Biomagnification
ofDDThasbeenstudiedcozofdetrimentaleffectontheenvironmentandonhumanandanimalhealth
Somaticmutationisageneticmutationwhichoccursinasomaticcellafterconception.Thesemutationscanleadtoa
varietyofmedicalissues.
canbeidentifiedbyexaminingthegeneticmaterialinaquestionablecellandcomparingittoacellfromelsewhereinthebody;theDNAinthetwocellswillbedifferent,despitethefactthatitisnotsupposedtobe
Therearetwotypesofcells:somaticcellsandgermcells.Germcellseventuallygiverisetogametes,whilesomaticcellsgiverisetoeverythingelse.Ifasomaticmutationoccursinutero,allofthecellsdescendedfromthesomatic
cellwill carry themutation. This results in a situation called geneticmosaicism, inwhich some of the cells in
someone'sbodyhaveDNAwhichisdifferentfromothercells.
Somaticmutationscannotbeinherited,becausetheydonotinvolvethegermcells.Parabensareagroupofchemicalcompoundswhicharewidelyusedaspreservatives,especiallyincosmetics.
arealsoutilizedbythepharmaceuticalindustry,andtheysometimesappearasfoodadditivesaswell. controversy,duetoconsumerconcernsabouttheirsafety, someproductsparabenfree areestersofparahydroxybenzoicacid concentrationofparabensincosmeticsisverylow,oftenlessthan1%; Healthconcerns primarilyfocusedontheirpotentialtoactlikeestrogencompoundsinthebody Butylparaben isusedasanantifungalpreservativeinvariouscosmeticproducts.Green engineering is the process and design of products that conserve natural resources, and impact the natural
environmentaslittleaspossible.Thetermisoftenappliedtohousing,butitcanbeusedforautomobiles,lightsorany
othersortofsystemordevicethatrequiresengineering,andincorporatessoundenvironmentalprinciples.
Biophotonsareweakemissionsoflightradiatedfromthecellsofalllivingthings.Plants,animalsandhumansgenerate
upto100photonspersecond,per1sq.centimeterofsurfacearea.Proponentsofalternativemedicineseeapossible
connectionbetweenbiophotonsandnaturalhealingtechniques.
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Molecularnanotechnology("MNT") isananticipatedmanufacturingtechnologythatwouldallowprecisecontroland
positionalassemblyofmoleculesizedbuildingblocksthroughtheuseofnanoscalemanipulatorarms.Ifwehadmany
millions or billions of suchmolecularscale arms,we could program them towork together to createmacroscale
productsbuiltfromindividualmoleculesa"bottomupmanufacturing"technique,asopposedtotheusualtechnique
ofcuttingawaymaterialuntilyouhaveacompletedcomponentorproduct"topdownmanufacturing".
Rigormortis isaconditionthatbeginstodevelop inthebodyafterdeathtakesplace.Essentially,theactionofrigor
mortisistobeginaprocesswherethemusclesinthebodybegintostiffen.Inmostsituations,thecorpsewillbeginto
undergotheprocessofrigormortisatroughlythreehoursafterdeathtakesplaceandwillcontinuetoexperiencethe
musclestiffeningforanywherefromthirtysixtoseventytwohours.
AfurlongisaunitofmeasureintheUKandtheUS, translatestoaneighthofamile,660feet,or220yards
Cryogenics isthestudyoftheproductionofextremelycoldtemperatures.Cryogenicshasawidenumberofpotential
andactualapplications, ranging from temperingmetals so that theywillbemoredurable to improving the toneof
musicalinstruments.
Whenmetalsare frozen cryogenically, the strengthof theirmolecular structure can increase, causing themetalitselftobestrongerandmoredurable.Manyhighendmetalproductsmaybesubjectedtocryogenicsaspartof
thetemperingprocess.
alsousedinthepreparationofspecializedmedications,andinpreservationofawiderangeofmaterials. Cryogenicfuelsarealsopopularforrocketsandshuttles. cryogenic preservation known as cryonics Humans and other animals can be deep frozen under controlled
conditionsinthehopesthatmedicaladvanceswillallowthemtoberesuscitatedatsomepointinthefuture
Coldfusionisablankettermforanynuclearfusionreactionthatoccurssubstantiallybelownormaltemperatures,but
ismostoftenusedtodescribea lowtemperaturereactionthatcanbeachievedusingrelativelynormalexperimental
conditions.Deuterium(ahydrogen isotope) ismostoften lookedatasthebestpotentialsourceofcoldfusionbased
energy.Itisreadilyavailable,haslittlewaste,andproducesgreatamountsofenergy
Neodymium magnets are the greatest of the rareearth magnets. Neodymium is the most powerful permanent
magneticmaterialofwhichwearecurrentlyaware.Affordable;usedquitefrequentlyinindustryandamonghobbyists
anddabblers.Forexample,everycomputerharddrivehasasmallneodymiummagnetwhichhelpsdirecttheneedle
thatreadsdata.Theycanalsobefound inhighendspeakersandscienceclassroomsaroundtheworld.downsides
magneticfieldlosessomeintensitywhentemperaturesaretoohigh;
LightDetection andRanging (LIDAR) is a technology that utilizes lasers todetermine the distance to an objector
surface. It isused inavarietyof industries, includingatmosphericphysics,geology, forestry,oceanography,and law
enforcement.LIDAR issimilartoradar,but it incorporates laserpulsesratherthanradiowaves.canalsobeused for
creatingthree
dimensional
topographical
maps
and
surveys
of
geographical
regions;
can
also
be
used
to
analyze
the
ocean floorand todeterminecanopyheightsandbiomassmeasurements. Italsohasapplications inseismologyand
hasbeenusedinstudiesofuplift,faultlines,andothergeologicalfeatures.
UsesofRadar
1. Detectionandsearchradar:suchasthe"earlywarningradar,"which isusedfor longrangedetectionofobjects,andTargetAcquisition (TA)RadarSystems,used to locatesurfacetoairmissiles (SAM).Thesetypesofradarare
frequentlyusedinthemilitaryandincoastalsurveillance,aswellasfordetectingcarspeedduringhighwaypatrol
2. Missileguidancesystemsareradarusedtolocatethetargetofamissile.Thisisoftenpresentinmilitaryaircraft.
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3. Radarforbiologicalresearch:birdandinsectradarareusedfrequentlybyscientiststotrackthemigrationpatternsofanimals.totrackthepresenceofbirds,especiallyvultures,nearlaunchingpads.
4. Airtrafficcontrolandnavigationradar:usedbyairportstoensurethesafetyofplanes,thistypeofradardetectstheproximityofanaircraftandidentifiestheidentityandaltitudeoftheplane.
5. Weathersensingradarsystems:mostlyusedtomeasureandlocateprecipitation;measurewinddirection&speedELISAmethodisatestwhichisusedinimmunologyandotherscientificfieldstodetectantibodiesandantigens.ELISA
standsforenzymelinkedimmunosorbentassay,whichreferstothefactthatantibodiescoupledtoenzymesareused
todetermine the resultsof the test.ELISAusesenzymeswhich reactwithantibodies to formcoloredproducts.The
developmentofcolor inanELISAtest indicatesapositiveresult.test isusedtodetectthepresenceofantibodiesto
infectiousdiseasessuchasHIV,hepatitis,andothers.
Smartgridisanelectricalgridwhichhasbeendigitizedsothatavarietyofdigitalmeasurescanbeusedtocontroland
operate the grid. The goal of installing a smart grid is to meet energy demands intelligently, promoting energy
efficiencyinadditiontocreatingamorereliablesourceofenergywhichisalsolessexpensive.
Seafloorspreading isaconstantgeologicphenomenonandaprimarydriverofcontinentaldrift.Theprocessbegins
whenthecrustisheatedfrombeneathbyupwellinginthemantle,sometimescalledamantleplume.Thecrustalong
thelength
of
the
rift
is
heated
by
the
underlying
mantle,
becoming
more
plastic
and
less
dense.
The
crust
rises,
creating
abroaddomeandwideningtherift.
LODscore(standsforlogarithmoftheodds)isarepresentationofthe likelihoodofa linkagebetweentwogenetic
traits.IftheLODscoreishigh,itmeansthatthetraitsarecloselylinked,andthereforeusuallyinheritedtogether.Asa
generalrule,iftheLODscoreis3orhigher,itmeansthatthereisahighprobabilityofgeneticlinkage
Opticalcamouflageisahypotheticaltypeofactivecamouflagecurrentlyonlyinaveryprimitivestageofdevelopment.
The idea is relatively straightforward: to create the illusionof invisibilityby covering anobjectwith something that
projectsthescenedirectlybehindthatobject.Creatingcompleteopticalcamouflageacrossthevisible lightspectrum
would require a coating or suit covered in tiny cameras and projectors,programmed to gather visual data from a
multitudeof
different
angles
and
project
the
gathered
images
outwards
in
an
equally
large
number
of
different
directionstogivetheillusionofinvisibilityfromallangles.
Ariftvalleyisageographicfeaturecausedwhenonearmofatriplejunctionbetweentectonicplates"fails"(i.e.,stops
spreading)and leavesa remnantcanyonlikestructure. largest riftvalley in theworld is theGreatRiftValley inEast
Africa.Alloftheworld's largestfreshwater lakesare inriftvalleys, includingLakeBaikal inRussia(theworld's largest
lakebyvolume,holding20%oftheworld'sfreshwater),LakeTanganyikainAfrica(secondlargestlake),LakeSuperior
intheUnitedStates(thirdlargest),andanumberofothers.Someriftvalleysarestillgeologicallyactive,butmostare
dormant.
Quantum
dot
is
a
particle
having
an
approximate
size
of
one
nanometer
which
has
the
display
properties
of
a
semiconductor.
Working:keytothequantumdotisintheelectrons.Electronsoccupyoneoftwobandsinamaterialscrystal.Byprovidingtheproperstimuli,anelectron,orperhapsmorethanone,canbeencouragedtomovefromonebandto
theother.Asitmovesfromonebandtotheother,itcreatesahole,whichispositivelycharged.Together,thehole
andtheelectronarereferredtoasanexciton.Normally,electronandthehole intheexcitonkeeptheirdistance
fromeachother.However, ifthecrystal isreduced insize, itcrowdsthisgap.Oncethathappens, itchangesthe
crystals ability to absorb and emit energy. At this point, the quantum dot is created. Different colors can be
obtainedbyreducingorincreasingthesizeofthequantumdot.
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Applications:MultiplequantumdotscanbeusedasLEDsinsigndisplays,cellstainingforlifescienceobservation,even inks that can aid in spotting counterfeits. Another security application that could soon be realized is
luminescentdust,whichcouldbeusedtotracktrespassersinrestrictedareas.mayalsobeusedtotransmitdata
DifferentTypesofWastewaterTreatmentTechnology
1. Aerobic wastewater treatment technology involves the use of good bacteria. The bacteria destroy harmfulmicroorganismsandintheprocessgiveoffbothcarbondioxideandwateraswasteproducts.
2. Microfiltrationorsyntheticmembranesbased: essentiallyfilterswhicharedesignedsmallenoughtocatchevenminusculemicroorganisms,thusremovingthem fromthewater.Multipletimesdonetoensureproper filtration.
generallyusedincombinationwithdecontaminatingchemicalslikeClwhichareremovedlater
3. Denitrificationusesmethanoltopurifywaterbyencouragingthegrowthofcertainbacteriawhichgiveoffcarbon.Thecarbonthenneutralizesorremovesnitratesfromthewater.Nitratescanbeharmfulforhumanconsumption
andhavebeenlinkedtoahostofhealthproblems,likecancer.
4. Ozone based: A generator produces ozone containing bubbles that are percolated throughout the watercontinuouslyoverasetperiodoftime,thusneutralizinganddecontaminatingit.
Bioprinting isanewareaof researchandengineering that involvesprintingdevices thatdepositbiologicalmaterial.
Thelong
term
goal
is
that
the
technology
could
be
used
to
create
replacement
organs
or
even
entire
organisms
from
rawbiologicalmaterials.
GeothermaldrillingisaprocesswherebyheatistakenfromtheEarthandusedinaproductivewayforenergyneeds.
Theheatcanbeuseddirectly forsomeneedssuchasspaceheating,butthe truevalue forthemassmarketcomes
fromthatheat'sabilitytobeconvertedtoother forms.Electricalgeneration isoneofthemostcommonreasons for
geothermaldrillingonanindustrialscale.
Forebayisahumanmadepoolofwaterinfrontofalargerbodyofwaterwhichmaybenaturalorengineered.
actasabufferzoneduringfloodingandstormsurges; trapsedimentanddebris.Thiskeepsthelargerbodyofwatercleanerandclearer; actasanaturalhabitattofish,waterfowl,aquaticplants,andothermembersofthenaturalworld; canalsobeusedinwetlandsmanagementandrestoration,inwhichcasethegoalisusuallytomaintainorrestorea
wetlandforfloodcontrolandenvironmentalreasonswiththeassistanceoftheforebay.
Genomics is the study of the collective genetic material in an organism. This scientific discipline is focused on
sequencingtheDNA inanorganismtoformacompletepicture,andthen identifyingspecificgenes inthatsequence
whichcouldbeofinterest.
Proteomics is the study of all the proteins thatmake up an organism. Proteomics doesn'tjust study the proteins
themselves,butalsothewaythey interact,thechangesthattheyundergo,andtheeffectsthattheyhavewithinthe
organism.Thesizeandcomplexityofthehumanproteome ispartofwhatmakesproteomicsaverycomplexscience.
there a huge number of proteins in the human proteome, about 400,000; these proteins also occur in different
locationswithinthebodyatdifferentstagesinaperson'slife,andcanchangewithinasinglecell
Opticalcomputingisacomputingtechnologyintheresearchandtheorystage.Theideawouldbetomakeacomputer
thatreliesentirelyonlight(photons)insteadofelectricity(electrons)todocomputing.
Theappealofopticalcomputersislimited,becausewithshortdistances,theyrequiremorepowerthanelectroniccomputerstodothesamecomputation.primarilyuseslaserstosendsignals.
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couldproducecomputerstensofthousandsoftimesfasterthantoday'scomputers,because lightcantravelthatmuch faster than electric current; could be used in large supercomputers to send data more efficiently than
electronics.
Planet X is a hypothetical planet that has been searched for throughout the years by many astronomers. While
searchingforPlanetX,astronomersfoundPluto,andXenaorEris,allclassifiednowasdwarfplanets
Smartdust isa termused todescribegroupsofverysmall robotswhichmaybeused formonitoringanddetection.
Currently,the
scale
of
smartdust
is
rather
small,
with
single
sensors
the
size
of
adeck
of
playing
cards,
but
the
hope
is
toeventuallyhaverobotsassmallasaspeckofdust. Individualsensorsofsmartdustareoftenreferredtoasmotes
becauseoftheirsmallsize.ThesedevicesarealsoknownasMEMS,whichstandsformicroelectromechanicalsensors.
mayeventuallybeusedtomonitortrafficandbetterdirectit,toaccompanysoldiersandalertthemtoanypoisonsor
dangerous biological substances in the air, to follow people around and track their activities, to track defects in
productsastheycomeoffofanassemblyline,andeventoenterhumanbodiesandcheckforphysiologicalproblems.
DNAelectrophoresis isamethodusedtosortDNAmoleculesbylength.PiecesofDNAaresuspendedinatrayofgel
andsubjectedtoanelectric field,whichcausesthemtomigratetowardoneendofthetray.TheDNAseparatesout
intobands,withthedistancefromtheelectrodecorrespondingto lengthofthestrand.Thetechniqueplaysarole in
identifyinggenesfordiagnosingdiseaseandforotherformsofgeneticresearch.
Carbonsequestrationreferstoeffortstocaptureexcesscarbondioxidefromtheatmosphere,condenseit,andstoreit
insomebenignway.
Carboncaptureandstorage(CCSD)technologiesare implemented insome limitedway inmanyfossil fuelpowerplants.technologyforcapturingisaheadofthetechnologyforstoring,whichisjuststartingtobeexplored
mostprimitiveformwouldbetosimplyplantmoretrees.moresophisticatedversion artificialphotosynthesis; AfterCO2isgathered,ithastobedisposedof.Currentapproachesinvolveinjectingitintothegroundorpumping
itto1000mdeepwatersatthebottomofthesea,whereitformslarge"lakes"thattaketimetodissipate
cyborgisanorganismwithbothartificialandorganiccomponents.
Althoughtheaverageprosthesisdoesnotfallwithinthedefinitionofcyborgtechnology,aprostheticdevicewhichemployssensorsto replicateapersonsnaturalgait,suchasaCLegsystem, isconsideredamoderndaycyborg
application.
development of RFID tag prolific cyborg application microchip implanted in a human being or animal topotentiallystoreinformation.
controversial application involves the utilization of insects and animals in the military for tactical combatpurposes.Eg: DARPA, has begun to explore the possibility of implanting insects with pupal data sensors for
surveillancepurposes,aswellasimplantingsharkswithsimilarcyborgsensorstodetectexplosivesunderwater.
Biopolymerisanyorganicpolymer.Biopolymershavebeenaroundforbillionsofyearslongerthansyntheticpolymers
likeplastics.Wellknownbiopolymersincludestarch,proteinsandpeptides,DNA,andRNA.
Bioinformaticsisafieldwhichusescomputerstostoreandanalyzemolecularbiologicalinformation.
Using this information in adigital format,bioinformatics can then solveproblemsofmolecularbiology,predictstructures,andevensimulatemacromolecules.
MainbranchesincludeGenomics,Proteomics,Computeraideddrugdesigning,biodatabase,dataminingetc
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most wellknown application of bioinformatics is sequence analysis. In sequence analysis, DNA sequences ofvariousorganismsarestored indatabases foreasy retrievalandcomparison.ThewellreportedHumanGenome
Projectisanexampleofsequenceanalysisbioinformatics.
otherapplications:predictingentireproteinstrands,learninghowgenesexpressthemselvesinvariousspecies,andbuildingcomplexmodelsofentirecells.
Positronemissionisabyproductofatypeofradioactivedecayknownasbetaplusdecay.
positronemissiontomography(PET): isotopesknowntoproducepositronemissionsare introducedtothebodyand followedastheymovethroughthebodyandproducegammarays. Isotopeswithshorthalf liveswhichwill
notcausedamagetothebodyareselectedsothatthePETscanwillnotbedangerous,andtheimagingstudymay
becombinedwithotherimagingtechniquessuchasMRItogetacompletepicture
PETscansallowdoctorstoimagefunctionsofthebody,perhapsmostnotablyinthebrain. Thescanisnotinvasive,providinganappealingalternativetosurgeryBiomimetics,sometimesknownasbionicsorbiomimicry,istheartoftakingnaturaladaptivestrategiesusedbyplants
or animals and translating them into engineering designs that can be used to implement products or tools. Some
unmanned aerial vehicles (UAVs) simulate variousaspectsof insectsused in flying and clinging towalls.Radar and
sonarallegedly
imitate
the
echolocation
faculties
of
bats.
An
artificial
pacemaker
mimics
acollection
of
organic
pacemakercellslocatednexttotheheart.
Xeroxcopier,genericallyknownasaphotocopier,essentiallyworkson theprinciplesof staticelectricity.Document
viewedasnothingmorethanblackorwhitespaces.Beneaththetransparentglasstray liesaflatbeltorrounddrum
calledaphotoreceptor.Thesurfaceofthisphotoreceptorismadefromspecialmaterialswhichcanbenegativelyand
positivelycharged indifferentareasatthesametime;"paints"thephotoreceptordrumorbeltwithstaticelectricity,
creatingapatchofpositivelychargedimagesofletterssurroundedbynegativelychargedareasthatwillremainwhite.
Nanobesarebizarre filamentary structures found in some rocks.Nanobesmustnotbeconfusedwithnanobacteria,
anothertypeofsupersmallcontroversialpossibleclassoflife.Thedifferenceisthatnanobacteriaaresaidtohavecell
walls,whereasnanobesarewalllessfilamentarystructures.
Trihalomethanesareagroupofchemicalsthatincludechloroformandstructurallyrelatedcompounds.Someareused
industriallyasrefrigerantsandsolvents.Thetermisgenerallyappliedtoasubsetofthesecompoundsthatarepossible
carcinogenicbyproductsofthechlorinationofwater.
Electronicmicroscope isa scientific instrument thatusesabeamofhighly chargedelectrons toexamineobjectsat
closerange.worksthesamewayastheopticalmicroscope.Theonlydifferenceistheelectronmicroscopedoesn'tuse
light; instead abeamof focused electrons areused to create the imageof the specimen.This also gives scientists
informationabouttheobject'sstructureandcomposition.
ArtificialPhotosynthesis: Researchers reliedontheHondaFujishimaeffect,whichwasdiscovered in1953anduses
titaniumdioxideasaphotocatalyst.Aphotocatalystacceleratesprocessesrelatingtolightand,inthiscase,energy.
producedtwodifferentresults:photoelectrochemicalcellsanddyesensitizedsolarcells. Photoelectrochemical cells, also referred to as PECs, use the electric currentofwater to createhydrogen and
oxygeninaprocesscalledelectrolysis.Electricitycanthenbestoredinthehydrogen,whichisanenergycarrier,
andtheenergycanbeusedlater,suchasinbatteries.
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dyesensitizedsolarcell,alsocalledaGraetzelcell.cellsuseasemiconductortocollectenergy,usuallysilicon.Indyesensitizedcells,thesemiconductorisusedtotransportthecollectedenergy,andthephotoelectrons,orenergy
particles,areseparatedandharnessedusingspecialdyes.
nootropic coinedtodescribeasubstancethatpositivelyaffectedbrainfunction.Althoughnootropicsarefrequently
referredtoassmartdrugs,notallofthesesubstancesaresynthesizedchemicaldrugs.Somenootropicsarevitamins,
minerals,orherbsthatenhancecognition.
Heliostatsare
scientific
instruments
that
use
amirror
to
reflect
the
light
of
the
sun
in
aspecific
direction.
Since
the
positionofthesuninrelationtotheEarthchangesthroughouttheday,mostheliostatshavesomesortofmechanism
builtintotrackthismovement.
Scramjet(SupersonicCombustionRamjet)usesatmosphericoxygenasanoxidizer,bypassingtheneedforanonboard
oxidizercompletely.Alargescoopatthefrontofthecrafttakesinair,whileonboardsystemsisolateoxygenfromthe
air,compressit,andintroduceittoastreamoffuelwhichthenusestheoxygentocombustandproducethrust.Fora
scramjetto intakesufficientoxygenforselfsustainingflight, itmustalreadybemovingatsupersonicspeeds.Forthis
reason,ascramjetmustbecoupledtoaconventionalrocketatthebeginningofitsflight.
Heat islandeffect,alsoreferredtoastheurbanheat islandeffect, isaneffectwheretheaveragetemperatureofan
area ishigherthannearbyruralareas.Theprimarycauseoftheheat islandeffect istheconversionofspace intoan
urbanenvironment thatabsorbsmoresunlightandstores it in large thermalmasses.Asecondarycauseoftheheat
islandeffect iswasteheatgeneratedbymassiveusesofenergy.Theheat islandeffecthasan impactnotonlyonthe
city itself,butalsoonnearbyareasdownwind,whichgenerallyseebetween10%and30%moreannualrainfallthan
areasupwind.
leastcompressiblematerialknown,withabulkmodulusof491gigapascals(GPa)isaggregateddiamondnanorods.get
theirstrengthfromthefamoussp2bond;areevendenserthanpurediamond;
Epigenetics isatermwhichisusedtodescribesituations inwhichgenesexpressthemselvesdifferently,althoughthe
underlyingDNA
is
the
same.
For
example,
ifacalico
cat
is
cloned,
the
clone
will
not
look
physically
identical,
despite
the
factthattheirgeneticcodeisthesame.Thisisbecausetheexpressionofgenesisinfluencedbyepigenetics.
SupercontinentcycleisageologiccyclewheretheEarth'scontinentsalternativelymergeintoasinglesupercontinent,
split intonumerouscontinents,thenmergeagain.Thecycle isestimatedtobe300 500millionyears long.Previous
supercontinentshaveincludedPangaea,whichformed250millionyearsago,Gondwanaland,whichformedabout600
millionyearsagoetc
Krmn line is the internationaldefinition for theedgeof space. It is located100 km (62miles) above theEarth's
surface,aroundwheretheAuroraBorealisforms.
GulfStream
is
an
ocean
current
that
runs
through
the
Atlantic
Ocean.
Although
it
starts
out
extremely
warm
in
its
southernreaches,temperaturedropsandsalinity increasesas itflowsnorth.Evenwiththedrop intemperature,the
GulfStreamisbelievedtoincreasethetemperaturesofthecoastalregionsofScotland,Ireland,England,andNorway.
Renownedforitssizeandwarmingcapabilities,theGulfStreamisalsonotableforitsincrediblespeed.
Genegunisadeviceusedinbiolistictransfection,aprocessusedtointroducegeneticmaterialtocellsthroughtheuse
oftinyDNAcoatedparticles firedathighvelocity intoaclusterofcells.Genegunsareused in laboratorysettingsto
conductresearch,developnewproducts,andtagsamplesofmaterials.
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genegunorabiolisticparticledeliverysystem,isadeviceforinjectingcellswithgeneticinformation.ThepayloadisanelementalparticleofaheavymetalcoatedwithplasmidDNA.Thistechniqueisoftensimplyreferredtoas
bioballisticsorbiolistics.
Usingagenegun,aresearchercanintroducenewDNAtoforceacelltoproduceproteinsitwasn'tmakingbefore.Genegunshavebeenusedextensively inthegeneticmodificationofcropsto introducegeneswhichmakecrops
more resistant todrought, increase thenutritionalvalueof crops,orallowherbicides tobeused safelyaround
crops.Genegunshavealsobeenusedexperimentallytodelivergeneticvaccines,andtointroduceDNAintoanimal
cellsfor
the
purpose
of
tagging
them
for
microscopy
or
for
genetic
engineering
of
such
cells.
Flywheelsareawayofstoringenergyintherotationalmomentum(kineticenergy)oflargewheelssealedinavacuum.
They areused as awayof storing and releasing large amountsof electrical energy, and although theirmethodof
storageisnonchemical,arraysofflywheelsaresometimescalledbatteries.
Yellowcake,knownasU3O8 tochemists, isaproductobtainedby treatinguraniumore.Rawuraniumoredoesnot
usuallycontainveryhighconcentrationsofthisusefulmineral,so itmustberefinedtopurify itandconcentratethe
uranium.Theproductionofyellowcakeisonestepintherefineryprocess.
Orogeny is amountainbuilding event caused by extreme volcanism (as in theDeccan Traps) ormovement of the
tectonicplates,
large
slabs
of
rock
that
make
up
the
Earth's
crust.
The
plates
float
on
top
of
aplastic,
superheated
mantle,madeofpartiallymeltedrock.Asthematerialinthemantlecirculates,thetectonicplatesslowlymovearound
ontop,creatingdifferentcontinentalarrangementsovertensorhundredsofmillionsofyears.
OneofthemostfamousandrecognizableistheHimalayanorogeny,whichoccurredaround55millionyearsago,when
the subcontinentof India collidedwith the Eurasian Platewhilemovingnorth. These twoplates pressing together
causedthecreationofgreatmountainrangesattheboundary,knowntodayastheHimalayas
Proteinengineering isamethodthatcanbeusedtodevelopnewtypesofproteins.Thisfieldofscience isrelatively
new,andoriginalwaysofcombiningproteinelementscontinuetobestudiedanddiscoveredbyresearchers.Thistype
ofengineeringallowsmaterialswithspecificstrengthsorfeaturestobedeveloped.
Geneflow isthetransferofalleles,variousformsofagenecodingforspecifictraits,betweendistinctpopulationsof
individuals. This can increase genetic diversity in some cases, and decrease it in others, depending on the
circumstances. Itoccursbothwithinpopulationsof the same species andpopulationsofdifferent species, in some
cases.
radiativeforcing: Inthecontextofclimatechange,amorespecificdefinitionofradiativeforcingagreeduponby
theIPCCistheextenttowhichafactoralterstheenergybalanceinthetroposphere.
Earth receivesenergy from theSun,mostly in the formof light, someofwhich isabsorbedandwarms theplanet,
causingittoradiateenergyintheformofheat,orinfraredradiation,andresultinginabalancebetweenincomingand
outgoingenergy.Variousfactorsaffecttheamountofsunlightabsorbedandtherateatwhichenergyisradiatedbythe
Earth.Whenthesefactorsremainconstantoveraperiod,theenergyflowscanbeexpectedtosettleintoequilibriumat
aparticular average annual temperature,with the same amountofenergy goingout as coming in. If anyof these
factorschange,itmightresultinamismatchbetweenincomingandoutgoingenergy,leadingtoanoverallincreaseor
decrease inglobalaveragetemperatures.Ageneraldefinitionofradiativeforcing isthedegreeofchange,positiveor
negative,tothisbalance,anditisnormallyexpressedinWattspersquaremeter(W/m2).
Conjugated antibodies are laboratorymanufactured compounds made up of antibodies combined with dyes,
chemicals,orproteins.Theseantibodycombinationsareusedforresearch,testing,andmedicaltreatment.
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Asynoptic chartprovides informationabout climate conditionsacrossa largearea,bigenough toencompassmost
majorweathersystems.SuchchartsareusefulnotjustformeteorologyonEarth,butalsofordepictionsofmagnetic
fieldsandotherphenomenaontheSunandothercelestialbodies.
Stemcelldifferentiation isaprocesswhereanunspecializedstemcelldevelops intoaparticulartypeoftissue, likea
matureredbloodcell.Thisoccursatallstagesof life,fromveryearlyembryonicdevelopment intoadulthood,asthe
bodyneedsaconstantsupplyofnewspecializedcellstofunction.
Severalfactorsareinvolvedincellulardifferentiation,incenvironmental&biologicaltriggersforvariouscelltypes Thenumberofdifferentkindsofcellsastemcellcanmatureintoarereflectedbyitspotency. totipotentcellcandevelop intoanykindofcellatmaturity.Suchcellsarefound intheearlyblastocystphasesof
embryonicdevelopment,wheneverycellneedstobeabletogiverisetoavarietyofcellsforanembryotodevelop
Asembryonicdevelopmentprogresses,thestemcellsbecomepluripotentinnature,withtheabilitytodivergeintoavarietyofcelltypes,butnotall.
Agenomemap isavisualdiagram that representsanorganismscompletegenetic structure.Manypeopleconfuse
genomewithgenes,butthedifferenceisthatthegenesarejustonepartofthegenome,whichistheentirestructure
consistingofothercomponentssuchasthedeoxyribonucleicacid(DNA)andribonucleicacid(RNA).
Gene targeting is theuseof genetic recombination technology to alter genetic sequences inembryonic stem cells.
Afterascientistaltersthegenome, it ispossibleto introducethecellstoadevelopingembryo inaprocedurecalled
embryonicinjection.
Aflooddamoperatesaspartofafloodcontrolsystemtoprotectcommunitiesfromuncontrolledfloodwaters.Such
damsdonotcreatereservoirstostorewaterforuseinthefuture,nordotheygeneratehydroelectricpower.Theycan
beinstalledbygovernmentagenciesandcommunities,andaresubjecttoregulationforsafety.
In genetics, certaingenemutationsare capableof causingdisease.Sometimes,everybodywith amutationdisplays
symptomsof that disease, and sometimes,only some of the people carrying themutation display symptoms. The
proportionof
people
who
show
symptoms
from
the
mutation
is
called
the
penetrance
of
the
gene.
Gneissisacommontypeofsurfacerockcomposedofdifferentmineralsandisclassifiedasmetamorphic.Oneofthe
mostcommonfeaturesofgneissrockisthatithasabandedorstripedinternalstructure,whichisusuallytheresultof
alternatinglayersofdarkandlightsilicatecompoundsthatmakeitup.
Dimethylol dimethyl hydantoin (DMDM hydantoin), is a common preservative ingredient found in cosmetics
production,constructionmaterials,andhouseholdproducts.Thechemicalcompoundistypicallyaddedtoproductsin
minute quantities as an antimicrobial agent. Certain consumer advocates fear that when combined with other
chemicals,thesubstancemaycausecancer.
Genesilencing
is
the
process
of
"turning
off"
agene,
thereby
preventing
it
from
expressing
in
the
form
of
protein
productionorotherformsofexpression.Thisprocesshappensnaturallyinmanycasesforthepurposeofregulatingthe
expression of genes and preventing potential damage from viruses.Gene silencing is also an important laboratory
technique,asdisablingageneisahighlyeffectivewayofdeterminingthepurposeofthatgene.
Geneexpressionoccurswhendeoxyribonucleicacid(DNA)isconvertedtoribonucleicacid(RNA)throughaprocesscalledtranscription.TheRNAisthenconvertedtoproteins,theprimaryfunctionalunitsincellsthatareinvolvedin
almostallcellularprocesses,throughaprocesscalledtranslation.
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Genesilencingcanoccuratatranscriptionaloraposttranscriptional level,meaningthat itcan interferewiththeprocessoftranscriptionorwithsome laterprocessthat leadstogeneexpression.Thegene itself isnotaffected,
butthevariousstepsthatleaduptoexpressionarenotallowedtoruntocompletion.
One transcriptional gene silencingprocess is referred to asDNAmethylation.Methylation involves attaching amethylgroup to certainpointson anucleicacid strandand can,basedon the circumstances,have avarietyof
differenteffects,someofwhichpreventtranscription.
RNA interference, or RNAi, is a common method of posttranscriptional gene silencing. In RNAi, small RNAmolecules
enter
into
aprotein
complex
that
cleaves
specific
RNA
strands,
preventing
them
from
being
translated
to
protein,therebypreventinggeneexpression.
Red biotechnology is a branch of biotechnology that deals specifically with human health care and methods of
treatment through the development ofmedicines such as antibiotics. The field can also involve research into the
manipulationofgenesthroughgermlineengineeringattheembryonicstageorgenetherapyinadultpatients.
Blue biotechnology is confined to the marine environment, while green biotechnology is focused on agricultural
applications.Whitebiotechnologyhasan industrialbase that involvesorganicenzymesand theprocesses that they
facilitate,andgraybiotechnologyhasasimilarbasis,wherecellsandnaturalorganismsareusedtocreatesynthetic
compounds.
Longshoredrift istheanaturalprocessdescribingacurrentthatoftenmovesmostlyparalleltoabeach'sshoreline.
mainproblemwith longshoredriftrelatestotheremovalofsandfromoneplaceandthedepositionof it inanother.
oneofthemostcommonpractices istobuildawallthatextendsfromtheshorelineintotheoceanatanangleof90
degreesinrelationtotheshoreline.Thishelpsbreakupthecurrentandstopsthedriftfromtakingplace.
Geosyntheticsaremanufacturedpolymericproductsusedwithmaterials suchas stoneor soilaspartofmanmade
projects, such as buildings or roads. These products or materials can be used, often in conjunction with natural
materials, for a vast variety of purposes. Geotextiles, for instance, can be used to separate or filter soil, and
geomembranesareoftenusedasimpermeablelinersforpondsorothermanmadebodiesofwater.
Adeepspaceprobe isaspacecraftdronethatmakesaonewaytrip intodeepspacetocollectscientific information
and broadcast it back to Earth. examples include the Pioneer and Voyager spacecrafts. Lithiumthionyl chloride
batteriesarecommonlyusedindeepspacemissionsaswellasroverslikethoselandedonMars.Thebatterieshavea
verylargestoragecapacity.
Probiotic bacteria, often called friendly bacteria, are livingmicroorganisms similar to those found in the human
digestive tract. Theynaturally occur in some foods andbeverages, such as fermented cheese and certain typesof
yogurt,andcanbeproducedseparatelyasdietarysupplements.Probioticbacteriaarealsousedincomplementaryand
alternativemedicinetoaidwithdigestivedisorders.B.acidophilus,lacticacidbacteriatypicallyfoundindairyproducts,
couldprolonglifebypreventingfoulinginthelargeintestine.
Western blot antibodies are large Yshaped proteins, or immunoglobulins, produced to use in the Western blot
immunoassay,atesttodetectanassociatedproteininatissueculture.
Aquantumwell isused to confine electrons at specific energy levels.Quantumwells consistof an extremely thin
semiconductorwith a smallband gap, restingbetweenmaterialwith a largerband gap.They are extremely small,
usuallybetween1and20nanometers.Theyaremostoftenusedinlaserdiodesandinfraredimaging.
Transmissionelectronmicroscopy (TEM) isan imaging technology inwhichelectronbeamspass throughverythinly
sectionedspecimens.Astheelectronsaretransmittedthroughthespecimenandinteractwithitsstructure,animage
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resolvesthatismagnifiedandfocusedontoanimagingmedium,suchasphotographicfilmorafluorescentscreen,or
capturedbyaspecialCCDcamera.
Aquantumwire isacableorawire,oftensimilar infunctiontocopperwire,butmadewithnanotubesofaspecific
element,usuallycarbon.Quantumwiresareusuallyconductors,butmayalsobemadeasinsulatorsorsemiconductors.
Thesewiresareidealforelectricalwiringfunctionsandforuseonspacecraftsbecausetheyaresmallerandlighterthan
theirmetalcounterparts.
Biometricstechnology
is
used
to
take
measurements
of
the
human
body,
generally
focusing
on
things
that
can
serve
to
uniquelyidentify individuals.usedinthefieldsoflawenforcementandsecurity.fingerprints,geneticsignatureoreye
structure.Othertypesmeasurelessphysiologicallyunique,butstillverydistinctive,aspects,suchasvoiceorgait.
Nanocomposite is amanmadematerialdesigned forenhancedperformance in anynumberofunique applications:
structural, functionalorcosmetic.Aswithothercomposites, thenanocomposite includesabasemedium,ormatrix,
composedofplastic,metalorceramiccombinedwithnanoparticlesinsuspension.
Fingerprintdusting isaprocedureusedbypoliceofficersatcrimescenes inanattemptto identifysuspects.Dusting
powder over commonly touched surfaces, or surfaces that are particularly relevant to the crime, in order to find
fingerprintsmighthelpofficersfigureoutwhoisresponsibleforacrime.
Powdersusedinfingerprintdustingcanvarybutaregenerallymineralbasedwithalowreactivity. Ridgesinhumanskinareresponsiblefortheexistenceoffingerprints.Naturaloilsintheskinmakethefingerpads
act somewhat like a stamp when they touch a surface. These oils create an outline of the unique ridges on
whatever surface a person touches, resulting in a fingerprint. Fingerprint dusting powder sticks to the oils,
highlightingthepatternoftheridgesandrevealingthefingerprint.
Fingerprintliftingistheprocessofsecuringcopiesoffingerprintsthatareleftatacrimescene. Acommonlyusedstrategyinliftinglatentprintsinvolvesusingcyanoacrylateester placingtheobject intoacontrolledenvironment.Asthecyanoacrylateesterisheated, itbeginstoreleasefumes.
Overaperiodof severalhours,exposure to the fumeswillcause theprints tobecome readilyvisible,making it
easiertophotographtheprintsbeforeanyattemptstocopytheprintsontoanothermediumaremade.
Powdersworkwellonsmoothsurfaces,whiletheuseofcyanoacrylateesterorevenproductslikesilvernitratearemoreeffectivewithsurfacesthatareribbedorotherwisenotsmooth.
Tectonicplates
arelarge,disconnectedchunksoftheEarth'scrust,floatingonthemantlebelow,composedofsoftmagma. varygreatlyinthicknessdependingonwhethertheyareoceanic(about5km)orcontinental(about50km). Continental crust generally consists of lighter rocks,while oceanic crust consists of heavier rocks. =>when an
oceanictectonicplatecollideswithcontinental,itcertaintoslipunder,orbesubductedby,thecontinentalplate.
3maintypesofplateboundaries,describedintermsofthewaythattectonicplatesmoverelativetoeachother1. transformboundaries,whereplatesgrindparalleltoeachother,2. divergentboundaries,whereplatesaremovingapart,and3. convergentboundaries,whereplatespressintoandsometimesundereachother.
These plate boundaries result in faults, rift valleys, oceanic ridges, oceanic trenches, mountains, island arcs,subductionzones,volcanoes,andothergeologicphenomena.
"Nanofabrication" refers to the fabricationof structureswith feature sizesmeasured in thenanometers,especially
below20nanometersonaside.Currenttechnologymostlypermitsnanofabricationonlyinatwodimensionalsense.
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Amajor subsetof currentnanofabrication are the technologies that fallunder thepurviewofnanolithography,whichbasicallyjustmeans"nanoscalewriting"andimpliesa2dimensionalresult.
In anticipation of running up against physical limitswith photolithography, computer companieshave investedbillionsofdollars inresearchfornextgeneration lithographytechniques.These includexray lithography(feature
sizes of 15 nm),double patterning (using a lowerresolution approach but patterning the same surface twice),
electronbeamdirectwritelithography(EBDW),extremeultravioletlithography,nanoimprintlithography,scanning
probelithography(whichcanmanipulateindividualatoms),andatomicforcemicroscopenanolithography.
Moreadvancedapproachestonanofabricationaremolecularselfassembly,whichhasbeendemonstratedinthelabhundredsoftimes,orpositionalmechanosynthesis,whichisattheearliestresearchstages.Bothareattempts
totakenanofabricationintothe3Drealm,whichwouldtrulyunlockitstechnologicalpower.
Reversegeneticsisanapproachtogeneticsresearchwhichtakesanunknowngeneticsequenceandattemptstofigure
out thephenotypewithwhich it isassociated.This is incontrastwithclassicalgenetics, inwhich researchers takea
knownphenotype,suchasstripesonacat,andtrytodeterminewhichgeneorgenescausethephenotypetoappear.
Labonachipdevices
more formallyknownas"MicroTotalAnalysisSystems" (TAS)aremicrofluidicsbasedsystemswhich integratemultiple
laboratory
type
capabilities
on
asingle
chip
only
afew
centimeters
in
size.
usesarerealtimepolymerasechainreactions(usedtoamplifysmallDNAstrandsintomoremanageablesamples),immunoassays,whichdiagnosediseasesbasedon antigen/antibodypresence,dielectrophoresis,used todetect
certaincelltypes,andbloodsamplepreparation,suchastheextractionofDNAfromredbloodcells.
LabonachipresearchcanbeconsideredasubsetofMEMS(microelectromechanicalsystems)Genetherapyisawayofinsertinggenesintoapatient'scellsandreplacingthepreexistingalleles,orgenevariants,to
performsometherapeuticfunction. Ithasbeenusedthus farprimarilytoreplacemutantdefectivegenes,oralleles,
withnormalalleles,butcouldintheorybeusedtoeditthehumangenomearbitrarily.Ifgenetherapywereappliedto
reproductivecellsinthegonads(thegermline),thesegeneticchangeswouldbeheritable.Thisprocesshasneverbeen
performed,but
it
has
aname:
germline
genetic
engineering.
RareEarthhypothesis claims that theEarth is rare,and that fewplanets can support complex life.TheRareEarth
hypothesisstandsincontrasttotheprincipleofmediocrity,whichassumesthattheEarthmustbeatypicalplanet,as
thereshouldbenothingspecialabouthumanityortheEarth.
Nanopaperisacuttingedgevarietyofpaperwithastrengthof214megapascals(MPa),greaterthan130MPaofcast
ironandapproachingthatofstructuralsteel(250MPa).Typicalpaperhasastrengthof1MPa.Thecellulosefibersin
nanopaperwereproducedbymakingasludgeofcellulose,similartothewaynormalpaperismade,butthenfurther
breaking itdownusingenzymes,mechanicalgrinding,andchemicaltreatmentwithcarboxymethanol.Theresultare
fibers1000timessmallerthanthefibersintypicalpaper.
JunkDNAisDNAwhichdoesnotappeartohaveanydiscerniblefunction.However,thetermjunkisabitmisleading,
asresearchonjunkDNAhassuggestedthatitmayactuallyplayanimportantroleintheevolutionaryhistoryandlives
ofmanyorganisms.Ratherthanjunk,thisDNAmayinfactbestoredforacriticalreason,andresearchershavestarted
exploring it. Some people refer it as noncodingDNA, referencing the fact that it does not code proteinswhich
express in thehostorganism'sphenotype.Whateveryoucall it, thepercentageofjunkDNA in thegenome isoften
quitehigh.Inhumans eg:95%ofthegenomeiscomposedofnoncodingDNA.
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InternationalSpaceStation(ISS)
isaresearchfacilityinlowEarthorbit,orbitingatanaltitudebetween320km(199mi)to345km(214mi). When completed in late 2011, the ISS will consist of sixteen pressurised modules (like small rooms) with a
combinedvolumeofaround1,000cubicmetres
hasbeencontinuouslystaffedsince2November2000;expectedtoremaininoperationuntilatleast2020 serves as a research laboratory that has a microgravity environment in which crews conduct experiments in
biology,
human
biology,
physics,
astronomy
and
meteorology
Operated as ajointprojectbetween the fiveparticipant space agenciesNASA,Russian Federal SpaceAgency(RKA),theJapanAerospaceExplorationAgency(JAXA),theCanadianSpaceAgency(CSA),andESA
Somemodulesare:Zarya(1st),Kibo,Destiny,Unity,Harmony,Tranquility,Columbus,Leonardo(latest,2011) largestroboticarmontheISS,Canadarm2weighs1,800kilogramsandisusedtodockandmanipulatespacecraft
andmodulesontheUSOS,andholdcrewmembersandequipmentduringEVA's.
Photovoltaic(PV)arrayspowertheISS;stationusesrechargeablenickelhydrogenbatteries(NiH2)forcontinuouspowerduringthe35minutesofevery90minuteorbitthatitiseclipsedbytheEarth.
ISS Environmental Control and Life Support System (ECLSS) provides or controls atmospheric pressure, firedetectionandsuppression,oxygenlevels,wastemanagementandwatersupply.
Spacedebrisobjectsaretrackedremotelyfromtheground,andthestationcrewcanbenotifiedofmanyobjectswith sufficient size to cause damage on impact. This allows for a Debris AvoidanceManoeuvre (DAM) to be
conducted,whichusesthrusterstoalterthestation'sorbitalaltitude,avoidingdebris
HorizontalGeneTransfer
or lateral gene transfer; genetic material is transmitted between organisms that arenotparent and offspring.Instead,thetwoorganismsareusuallyunrelated,andareoftenofdifferentspecies.
most commonway inwhich singlecelledorganisms,bacteria inparticular,acquirenewgeneticmaterial.allowsbacterialspeciestomaintaindiversity.threewaysinwhichbacteriacanexchangegeneticmaterialhorizontally.
TransformationisaprocessinwhichbacteriaingestnakedDNAorRNAmoleculesandexpressthemwithinthecell. Intransduction,geneticmaterialistransferredbybacteriophages,whicharevirusesthatinfectbacteria. bacterialconjugation,inwhichgeneticmaterial,oftenplasmids,istransferredviaintercellularcontact.Islandgigantismisabiologicalphenomenonwhereanimalsthatliveonisolatedislandstendtogrowlargerbecauseof
alackofpredatorsandcompetitionwhichwouldotherwisebepresentonthemainland.Ratherthanbeingcausedbya
novelselectionpressure,asisthoughttobethecasewiththecomplementaryphenomenonofislanddwarfism,island
gigantismiscausedbytheremovalofconstraints.Theresultareorganismsthatswelltoponderoussizes.Therearethe
famousGiantTortoises,foundontheSeychellesandGalpagosIslands.
Petroleumispredominantlycomprisedofvarioushydrocarbonsingas,liquid,orsolidstates.Crudeoilandnaturalgas
aremembers
of
this
group.
One
hydrocarbon
in
crude
oil
is
paraffin,
which
is
commonly
known
in
food
preservation.
During the refining process, various temperatures yield different products, and the temperature atwhich thewax
beginstoemergeinthefueloroilisknownasthecloudpoint.
SuperEarthisatypeofextrasolarplanet(exoplanet)moremassivethantheEarthbutlessmassivethanagasgiantlike
Jupiteror Saturn.The concept is relativelynew (2003). Scientificpapers variouslydefine a SuperEarth as aplanet
betweenoneandtenEarthmasses,orasaplanetbetween5and10Earthmasses
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SETI,or theSearch forExtraTerrestrial Intelligence, isaprojectwhichaims todetectextraterrestrial intelligent life.
SETI primarily uses radio telescopes to search for extraterrestrial signals, although optical telescopes and other
methodshavebeenproposed.
Casimireffectreferstothetinyattractiveforcethatappearsbetweentwounchargedplatesinavacuum.ThisCasimir
forceisonlymeasurablewhentheplatesareextremelyclosetogether.Casimireffectreferstothetinyattractiveforce
thatappearsbetweentwounchargedplates inavacuum.ThisCasimir force isonlymeasurablewhentheplatesare
extremelyclosetogether
fumaroleisaholeintheEarth'scrustwhichventsgases.Fumarolesareusuallyfoundaroundareasofvolcanicactivity,
althoughtheycanappearanywhere.Ifenoughgroundwaterispresent,theventmayturnintoahotspring,creatinga
supplyofbubblingnaturallyhotwaterwhichisheatedbytheescapinggases.
Swarmrobotics isanapproachtoroboticsthatemphasizesmanysimplerobots insteadofasinglecomplexrobot.A
robotswarmhasmuchincommonwithanantcolonyorswarmofbees.Noindividualinthegroupisveryintelligentor
complex,butcombined, they canperformdifficult tasks.Swarm roboticshasbeenanexperimental field,butmany
practicalapplicationshavebeenproposed.
humiditymap isamapwhichprovideshumidityvaluesforaregion,usuallyexpressed intermsofrelativehumidity.
Suchmapscanbeusefulinawidevarietyofapplications.Theyareoftengeneratedbygovernmentagencies,although
weatherforecastingcompaniesandprivateorganizationsmayalsogeneratetheirownhumiditymaps.
Anarcticfrontisaboundarybetweenanarcticairmassandapolarairmass.Thisboundarytendstoexistmoreorless
continuallyinnorthernlatitudes,althoughitwillchangelocationasseasonalweatherpatternsareexpressed.
Molecularmedicine involvesapplyingknowledgeaboutthemolecularbasisofdiseaseandhownewclinicalpractices
canbebroughttobear.It includespractices,suchas interventionsonthecellularand/orDNA level includinggenetic
and cellular therapies, and incorporating new understanding, such as those that have grown out of studying the
posttranslationalmodificationofproteins. Itoftenmakesreferencetosuchspecialtiesasgenomics,proteomics,and
bioinformatics.
transgene is a section of genetic material from one organism which appears in the DNA of another organism.
Depending on a number of factors, the transgenemay fail to express, may express in away different from that
observed intheoriginalorganism,ormayexpress intheneworganism inexactlythesameway itdid intheoriginal
one.Ageneisidentifiedasatransgenewhenithasbeensequencedinonespeciesandlateridentifiedinanother.
Siderealtimereferstothe lengthofdaysandothermeasurementsoftimewithrespecttostarsotherthanoursun.
Whereasasolarday lasts24hours,asiderealday isaboutfourminutesshorter.Ineveryday life,solartime isalways
used,butastronomersoftenfinditusefultousesiderealtimewhenexpressingtheapparentmovementofstarsinthe
sky,asobservedfromearth
Inthenucleus,genesaresectionsofDNAthatcodeforspecificproteins inthecell.This isreferredtoasthegenetic
code.AlloftheDNAisnotincludedaspartofthegeneticcode.TherearelengthsofDNA,calledintrons,whichdonot
codeforproteins.ThepartsoftheDNAformthegeneticcodearecalledexons.
Jatropha is a genus of plants, trees, and shrubs native to South America and the Caribbean uses: ranging from
compoundswhichcanbeusedasvegetabledyestooilswhichcanbeutilizedintheproductionofbiofuelsespbiodiesel
Tribology,a science that studieshow frictionand lubricationwork together,hasbeenused sinceancient times.By
understandingfrictionand lubrication,atribologist isbetterabletoreducethecorrosionofnumerousmachinesand
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products.Therearefourthingsthatatribologistmuststudytopreventwearandtear:abrasion,erosion,corrosionand
adhesion.
MEMS stands for Micro ElectroMechanical Systems, referring to functional machine systems with components
measuredinmicrometers.MEMSisoftenviewedasasteppingstonebetweenconventionalmacroscalemachineryand
futuristicnanomachinery.
modernMEMSfabricationtechniquesarelargelybaseduponthesametechnologyusedtomanufactureintegratedcircuits,
that
is,
film
deposition
techniques
which
employ
photolithography.
Mostoftenmentioned in conjunctionwithMEMS is the ideaof a "labonachip," adevice thatprocesses tinysamplesofachemicalandreturnsusefulresults.
MEMSare fabricated inoneof twoways:either throughsurfacemicromachining, inwhich successive layersofmaterial are deposited on a surface and then etched to shape, or through bulk micromachining, where the
substrateitselfisetchedtoproduceafinalproduct.
Surface micromachining is most common because it builds on the advances of integrated circuits.Variousmicroscalegears,pumps,sensors,pipes,andactuatorshavebeenfabricated
ExamplesofmoderndayMEMSuseincludeinkjetprinters,accelerometersinautomobiles,pressuresensors,highprecisionoptics,microfluidics,monitoringofindividualneurons,controlsystems,andmicroscopy.
Eugenicsisasocialmovementwhichinvolvesmanipulatinghumangeneticinheritancetobringoutthetraitswhichare
believedtobebest.Eugenicshasbeenusedhistoricallyasanargumentformandatorysterilizationandavarietyof
other policieswhich have been targeted at the lessermembers of the societywith the goal of eliminating their
geneticheritagefromthegenepool.
Activegalacticnucleusisasmallregion,betweenabout1and100lightyearsindiameter,atthecenterofagalaxythat
emitsprodigiousamountsofradiationoversomeoralloftheelectromagneticspectrum,fromtheshortestgammarays
tothe longestradiowaves.Activegalacticnucleiareamongthemostenergeticphenomena intheuniverse,beating
outevensupernovaeintermsofluminosity.
Inertial confinement fusion (ICF) is a method of achieving nuclear fusion by quickly compressing and heating a
material.Thisprocessisusuallydonewithhighpoweredlasers,whichareallfocusedontoasmallpellettorapidlyheat
itup.Theintenseheatingvaporizesthematerialinsidethepellet,creatingashockwavewhichishotanddenseenough
to cause thematerial to fuse.Thebasic ingredientsof an ICFpelletaredeuteriumand tritium.The fusion reaction
between deuterium and tritium is much easier to achieve than any other reaction, and so a powerproducing
deuterium/tritiumreactoristheprimarygoalofmodernfusionresearch.
Cosmic dust is a substance which is found throughout the Universe. It consists of small grains of material and
aggregatesofsuchgrains,withacompositionwhichcanvaryradically,dependingonthecircumstances inwhichthe
dustisformed.
Nutrigenomics isacombinationofnutritionandgenomics.describesafieldwhich isconcernedwiththerelationship
betweendietandgeneexpression.Nutrigenomic research investigatesquestions suchashow food influencesgene
expression,andhowgenesinfluencethewayindividualsabsorbandmetabolizedifferenttypesofnutrients.
Lagrangepointsarestablegravitationalpointsinspacewhereanobjectcouldbeplacedanditwouldremainatafixed
positionwith respect toabodyorbiting theSun, suchas theEarth.Everyorbitingplanethas five Lagrangepoints.
Earth'sLagrangepointsarecalledL1,L2,L3,L4,andL5.Lagrangepointsoften feature indiscussionsaboutspaceor
sciencefictionbecausetheywouldbeideallocationstobuildspacestations.
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Photonicsisabroadfieldofstudythatinvolvestheresearchandapplicationoflightinallofitsmanyforms.Thefieldis
notonlyinterestedinthevisiblelightspectrum;ultravioletlightandinfraredlightareveryimportantaswell.Thefield
ofphotonicswasoriginallyaimedatapplying light to tasks thatcouldpreviouslyonlybesolved throughelectronics,
suchastelecommunications.Themodernfieldseekstocontinuethisendeavorandtoexpanduponitbysearchingfor
any and all applications for light. Photonics draws from and contributes to several other fields, such as quantum
electronicsandmodernoptics.
usedinmanydifferentindustries,rangingfromconsumerelectronicstorobotics. BarcodescannersandDVDreadersarebothlightbasedtechnologies. Inmedicine,lightintheformoflasersisusedforeyesightcorrectionandtattooremovalaswell. Militaryapplicationsincludethedetectionofinfraredlighttoexposeheatsourcesinthedark.Someapplicationsof
photonicsareusedentirelyforentertainment;theseincludelasershowsandholographicart.
XSeed4000isthelargestbuildingeverfullyenvisionedanddesigned.Itis4kmtall(13,123feet),witha6kmbase.X
Seed4000wasdesignedbyTaiseiConstructionCorporation
W54NuclearWarhead:isthesmallestnuclearwarheadtobedeployedbytheUnitedStatesandthesmallestknown
nuclearwarhead ingeneral. It is similar in size toacomputerprinter,withadiameterof27cm,about40cm ,and
weighingslightly
over
23
kg
Atokamakisatoroidal(doughnutshaped)magneticplasmaconfinementdevice,theleadingcandidateforproducing
magneticfusionenergy.
tokamakischaracterizedbytheuseoftheplasmacurrenttogeneratethehelicalcomponentofthemagneticfieldnecessary for stable equilibria. This can be compared to another toroidal magnetic confinement device, the
stellarator, inwhich allof the confiningmagnetic fields areproducedbyexternal coilsand there isanegligible
currentflowingthroughtheplasma.
Whydoughnutshaped?Thedistinctiveshapeofthefusionreactorisnecessarybecauseofaparticularpropertyofadoughnutthatasphere(forexample)doesnothave.Essentialytheproblemisthehairyballtheorem.Ifasphere
hashairgrowingoutofitthenitisimpossibletocombitsothatnohairsticksup.Howeverahairydoughnutcanbe
socombed.This is importantbecausea fusionreactor isahairydoughnutwiththehairbeingthemagnetic field
lines.Astrandofhairthatisstandingonendwouldbeaninstabilityinthereactor.
FarnsworthHirsch fusor is a device for generating nuclear fusion reactions. FarnsworthHirsch fusors use strong
electric fields to contain the fusionplasma,unlike themore common tokamak design,whichusesmagnetic fields.
Farnsworthfusorsaregenerallyquitesimpletobuild,andnumerousamateurshavebuilttheirown,oftenfromspare
parts.basicprinciplebehindtheFarnsworthfusor,inertialelectrostaticconfinement(IEC),wasfirstnoticedintelevision
vacuumtubes.
Higgsparticles,
also
known
as
the
Higgs
Boson,
are
units
that
have
been
theorized
in
particle
physics
but,
as
of
yet,
havenotbeenproventoexist.TheyaresometimesreferredtoastheGodParticlebecausetheyarethoughttobeall
aroundus,yetnearlyundetectable.ThesearesomeofthesametraitspeopleassociatewithGod,thusthereasonfor
thename.Higgsparticles are thought to exist in a field known as theHiggs field. In general,Higgsparticles could
explainwhatgivesmattertomass,andthuscomposestheuniverse.
Oneofthechallengesofcancertreatmentishowtodestroymalignanttumorswithoutdamaginghealthycells.Anew
methodthatshowsgreatpromiseforaccomplishingthisemploystheuseofasuicidegene.Asuicidegene isagene
whichwillcauseacelltokillitselfthroughapoptosis,orprogrammedcelldeath(PCD).PCDisaseriesofbiochemical
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eventswhich cause the cellmembrane to dissolve, the cell to shrink, and the nucleus andDNA to fragment. The
processalsoprovidesforthebodyscleanupofthecellulardebris.
2methodsofsuicidegenetherapy: Genedirectedenzymeprodrugtherapy,virusdirectedenzymeprodrug Genedirectedenzymeprodrug therapy (GDEPT)usesagene taken from thecancercelland thenmodifiedwith
othergenestoformenzymesthatareharmlesstohealthycells.Thisforeignenzymeisinsertedintothetumorcells
whereitreleasesaprodrug,whichisasmallmoleculeharmlesstohealthycells,butdestructivetocancerouscells.
Themodifiedsuicidegeneconvertsthenontoxicprodrugintoacytotoxicsubstance.
virusdirectedenzymeprodrugtherapy:usesavirus,suchaherpessimplexorcoldvirus,asthecarrier,orvector,todeliverthemodifiedgenestothecancercells.AstudybeingconductedbyMethodistNeurological Institute in
Texaswillbeusingherpesvirustodeliverthesuicidegenestobraintumors.ThepatientswillbegivenValtrex,a
drugusedtotreattheherpesvirus.Thesuicidegenesareexpectedtobreakdownthetumorcellstosuchadegree,
thanwhenthedrugtreatstheherpescarrier,thecellshouldbedestroyed.
Suicidegenetherapyisnotnecessarilyexpectedtocompletelyeliminatetheneedforchemotherapyandradiationtreatment for all cancerous tumors. The damage inflicted upon the tumor cells, however, makes them more
susceptible to the chemoor radiation.Thisapproachhasalreadyproveneffectiveagainstprostateandbladder
cancers.Theapplicationofsuicidegenetherapyisbeingexpandedtoseveralotherformsofcanceraswell.
"Mitochondrial Eve" is the name given by scientists to the woman who is the matrilineal most recent common
ancestor of all living humans. That means that all living humans have mitochondrial DNA derived from hers.
MitochondrialEveisthoughttobeawomanthatlivedineasternAfricaabout140,000yearsago.
gravitationallensisanastronomicalphenomenonobservedwhenamassiveobject,likeaclusterofgalaxiesorablack
hole,bends light fromaverydistant lightsource,suchasaquasar (youngandbrightgalaxy).Thisoccursdue tothe
gravitationalwarpingofspacetime firstdescribedbyAlbertEinstein inhisgeneral theoryof relativity.Gravitational
lensingcancausedistantquasarstoappearinlocationswheretheydon'treallyexist.
Tacticalnuclearweaponsarerelativelylowyieldnuclearweaponsintendedtobeusedonthebattlefieldinwar.Thisis
incontrast
to
strategic
nuclear
weapons,
which
are
designed
to
target
large
cities
and
military
facilities.
AugmentedReality(AR)referstocomputerresearchthataimstoproduceinformationsystemsthatmergerealworld
informationseamlesslywithdigitalinformation.
The science of genetics focuseson genes as the units of heredity, andhow that information is transmitted.At an
entirely different level, genomics focuses on the entire genomeof an organism,which comprises allof its genetic
information.The fieldofgenomics isdivided intoseveralcategories, including functionalandcomparativegenomics.
While functional genomics is concerned mainly with how genes and the genome function in a given organism,
comparativegenomicsfocusesoncomparinggenomesfromdifferentspecies.
Atsunami,
or
tidal
wave,
is
created
when
asubstantial
volume
of
water
in
the
oceans
is
displaced,
resulting
in
awave
front which eventually reaches human coastal settlements. A tsunami can be caused by an earthquake, volcanic
eruption, landslide ormeteorite impact, though earthquakes are by far themost common cause.While a normal
tsunamitakenaloneisaquiteimpressive,uniqueevents(massivelandslidesorasteroidimpacts)cantriggertsunamis
solargeanddifferentfromtheirsmallercounterpartsthattheyhavebeencalledsupertsunamis,ormegatsunamis,for
thepurposeofclassifyingthemseparately.
Wastevegetableoil (WVO) isvegetableoilwhich is leftover fromotheruses,most typicallyuses in the restaurant
industry,suchasdeepfryers.ThereareanumberofapplicationsforWVO,rangingfromrenderingitforuseinanimal
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feedtoprocessing itsothat itcanbeused inalternativefuelvehicles.processthevegetableoilforuse incosmetics,
animalfood,andotherproducts.
Ocean thermalenergy conversion, sometimes referred toasOTEC, isa formof renewableenergy thatutilizes the
differenceinoceantemperatureatvariousdepthsandconvertsittoaheatengine.Theheatengineconvertsthisheat
energytoamechanicaloutput.
3typesofOTECsystemsincludeclosed,open,andhybrid. Theclosedcyclesystemusesaliquidthathasaverylowboilingpointtomoveaturbinetocreateelectricity.Thisis
accomplishedbysendingwarmoceansurfacewaterthroughaheatexchangerwherethefluidisvaporized.When
the vaporexpands, itmoves the generator.Coldoceanwater,drawn atmuchdeeperdepth, is sent through a
differentheatexchanger,whichthenreducesthevaporbacktoliquidform.
Anopencyclesystemuseswaterfromtheoceanthatistheclosesttotheequator,sinceitistypicallythewarmest.Warmoceanwaterthat isplaced insideofa lowpressurecontainerwillbegintoboil.Asthesteamexpandsand
leavesthelowpressurecontainer,thesaltremains.Thesteampowersalowpressureenginethatisattachedtoa
devicethatcreateselectricity.Itisturnedbacktoliquidformbyexposingittocoldtemperaturescreatedbyocean
waterfromalowerdepth.
Thehybridsystemcombinescomponentsofthe firsttwomethods.Warmoceanwater ispulled intoacontainerwhereitisturnedintosteam.Thesteamthenturnsalowboilingpointliquidintovapor,whichpowersaturbineto
createelectricity.
Scanningtunnelingmicroscope(STM) isan innovativetypeofmicroscopewhich, insteadofusingreflecting light like
conventionalopticalmicroscopes,usesquantumtunnelingbetweenasampleandaprobetiptoimagethesurface.The
resolutionsachievedbyanSTMcanbeashighas0.1nmlateralresolutionand0.01nmdepthresolution.Thisisafew
timeshigherthantheresolutionsachievableusingthebestelectronmicroscopes.
SpaceShipTwo isa spaceplanedeveloped inajointventurebetween theVirginGrou