A desiccatorthat's

unbreakableand

beautiful . . .

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Wii Vt %tt (i ii I'cLIi tl W In I III !

oI(l it IfP, Lii I icii- lii" tor miss \I iL II Li iii ri(i Ii ).uSS'. (5It5

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Ss 1 -t',i 2ff 5 0 a (J ci ' 17lii sa'5'youL re ili. \sk souir LabwortorsSuLpps D)eu Lir for ouir new' C(t,i-ol4 or S\ ito Dept. 2 1(43, Na tI4Lrw

1 .ahbsare Dt)sisioni, Rochester YN.'4(0-2.

NALGENE LABWARE DIVISION

NAL-LGECircle No. 96 on) Reciders' Service Card

iluect a11l oi- nliost of thlC cost Is) i%rliai'2sLhscriptiOIi rates. Somiie are org;ails ofsc,icIetiC,s thaIt has"eIVcoC iitahle'pr)IiCli-cat.lton I-eserv es. Perhaps ill ctlort to

oht.iai direct sOlhSicdes> m1is he the' Illost

1l i ieht hC a1dniniIStiCdlChs 1sVecIIac:ii1iiiittie of ttle Naltiooll AC,itdceiiof SciCe1"s. Suidies on .10 onltinninL'baIiss I1f ise 10lo II'tlCOIie11 li i\ci nlnllent. nLit ats 't11n Clni >c'ItecV mci-..rti C sOlile' ot thlc t(Iorindauonls nneht}l bet5 ifI (-tie o ltco liriLte to tli.iltait[I tfleCjilitlsl\ o1aid lailtiti ot'f A nl iIcricncie'ntific pLhifi.ltioil.

H sioor (RcNU.ni1)lstI)' I h1'" 1i'/t ,of \ (il 0/0,l5>}( olln l/bc ( onl .itNc Nr cid 1(I-)))

TIhe Iiiiversitv in Manvi Mirrors

C. \\ et ( IL 1C1IrlImaI1 has1 take ii theopliort hLu ItS tli S ICS\iC\\ ot I h/ ( '/O.Cd( aporonon. .:icii .i .i.ih II

( o(ft4 1 'lh.. p. f64) to driag lhis Oss II

sr0n1 ipbo\ tt) SaLti hr- ( iate. D)CeSitC hlis05 CrisitliftericCd[ieCr'eCCeS tO h)Lit tiC-

ii'[ets. hil'lai moList ofS this pronloWince1-mlcii ts 1-1is finl.l *rllestiOnl W'\hat is .1

lil[i CeritSIt\ iS CCertajIll theC iiiOSt impor-tailnt CoLIe'stiol to alsk. 1il di ual alsS\ eCrs\rrill raii"e hirim lalioratOrv-lihlrars C0ii-cept of (lctachedl epermilelltltiol anda"Ccti'c cicit'vitv tot e ihidaoesrt}r v ofcollectiv t insrI e'lilellt in controsversialissuLes o1 tie niomiienm. Alsoi. the pictUrcsOt thIle iell strLideiit-tealcher relationshlips ill s aIrs from 0otie shoiws inz a harshmaIster-alilprelltice airraTiiyemnit to oniein ws hich teacher andirl studelt are nlcpict-Cr1 atS SolI IrOthler-S engage1'£Cd il a111 ill-teiIsC ililiriiV inltto the Uiltimiiate IlcallinizLit eSeiS[X'tlilC.

\Wliatev S siotis des elop t'ir thticIealLitIi'e'SitV. ho\sseser, Valst aiiioriitS it'Sripiirt itI loltie atirland inlsodill ireiicedeli. C oncerninc, this p)Oillt, ChLirci-ialtil alilicar-S tO lieUnrea,istic. WVe situIp-Is canl int irnore the fcelinics of' the'iltajorits of the electorate.' T[ic clec-toratc hlsset tot liecCOnsiMiCCe thlalt LIuli-crsities p(oSeC nSLli\iIe Insight tiLto their

LiSS \s itlii IeSS. Ulltil sLICli a das ar-ris es. hoth lLblic anItd pris atC nIvis ersi-ties I List tCeilpre- dcelisiim s\ ii morethai JLst a (cYrlciC nca,ss;mareness oft' prilblicopinioiL. Hy p crisy tieed not resLilt. Theclcctorlate ha. lon- aco adjuLsted to the4ceineranlfaicIt that strdLents atnci tprol'cs-soers dIo tiit ac.ree xs itII nian or. ill theeclctorates niind, silost ot tthe cLirreiitpolitical. moral, arnd reliciOLls Cons ic-iziniis. lie clectoratese ill tiscer adjuist.

Now-from Tracerlab

Cytidine Diphosphocholine-1,2-" C chloride

O-Phospho-DL-Serine3YC0-Phosphoethanolamine-l ,2-1 C

Phosphorylcholine-1,2- C chloride

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Phosphatidyl L-Serine3Y3 C

Phosphatidylcholine-1,2- 'C Chloride

and tor otherreliable radioactivecompounds, nuclides,

sources and accessoriesWrite for Catalog 70

-the complete source

n TRACERLABA D vision of

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Circle No. 88 on Readcrs' Service Ccard

S IE-N(I Vol 1(64

however, to having these cherished be-liefs treated with insolence. Nihilists aremaking the most of this fact. In addi-tion, well-meaning students and falcultyhave too often confused the lofty con-cept of freedom of expression with free-dom to give pointless, or even perni-cious. insult and offense. To me. "per-forming in a manner which pleases themajority of the electorate" does notmean conforming to popular whims or

beliefs, but it does mean approachingour task with dignity and understanding.

STANLEY N. DAVISDepart-tment of Geoloov,University of Missouri,Coltinbia 65201

PULSE in the City of the Future

In his article "Science and the city:The question of authority" (28 Feb..p. 902). Carroll has presented a com-prehensive picture of the Departmentof Housing and Urban Developmentresearch activities. Also his reference67 alluded to "HUD's most substantialtechnological study to date." the NewSystems Study of Urban Transporta-tion which is summarized in a HUDpublication "Tomorrow's Transporta-tion" (May 1968). Among the new

technological developments suggestedin the study is the Public Urban Lo-cator Service (PULSE). a system whichcan automatically and rapidly reportthe location of many moving objects(people. vehicles, or goods). whereverthey might be. to a central point wherethey can be rerouted if necessary to

meet an emergency or changed require-ments. This svstem could improve thefunctions of police operations, publictransit. ambulance service, fire con-

trol, and movements of goods. to namea few.PULSE is being developed under

HUD leadership, assisted by the de-partments of JuLstice, Post Office, Health,Educationi, and WVelfare, and Transpor-tation, the Federal CommlLunicationsCommission. and private industry: andit is hoped that it can be tested in thenear future. This is an exsample of anuLrban utility which can jointly serve theneeds of municipal agencies, commer-cial interests, and private individualsand illustrates the value of HUD re-search in nonhoulsing areas.

STEP-HEN J. KAHNEDepartmnent of Electrical Engineering,Uniiversity of Minniiesota,Minnzeapolis 55455

23 MAY 1969

,. drawn by Durrum

Mutntlemoglobin

I

E-4<0- '/ WHICH IV)

)O ms

CONIMUTAN

Normal Hem-loglobiin

REMOGLOBINPAINS THEIT SUBUNIT?

,R 1'(> .11C 1Y jl NoEY F-. .L'I I IN .NAN) l:l i S if l;1IN :'(' 'I iIF

- wDURRUMPr'Circe No 30on Roder' Srvic Cor 90

.:i:.;.:..,."'

TINIE -

Even a minor molecular rearrangement can have a dramatic effecton chemical activity. These profiles"" recorded by a Durrum-Gibson Stopped-Flow Spectrophotometer reveal a 40-fold differ-ence in azide-hemoglobin reaction rates. One reaction is withnormal hemoglobin, the other with a mutant containing alpha-chain tyrosine residues in place of the usual proximal histidines.

Equilibrium constants would not have hinted at this difference;only kinetic tests with the Durrum-Gibson instrument permit theuse of this new technique for classifying mutant types.

The Stopped-Flow Spectrophotometer is a versatile, general-purpose system that is widely used to determine the kineticcharacteristics of reactions with half-times in the 5-millisecondto 50-second range. A temperature-jump accessory is availablefor studies involving even faster reactions, down to 10 micro-seconds or less. The accessory is uniquely designed to allowcombination T-Jump/stopped-flow studies of pseudo-equilibriumreactions.For complete information on the D-100 Series Stopped-FlowSpectrophotometer and its applications, contact.. DurrumInstrument Corporation, 3950 Fabian Way, Palo Alto,California 94303, Phone (415) 321-6302.

P"I.s.-

Circle No. 30 on Readers' Service Card 90)7

ItIJAViOXYG RAPH

Developed in collaboration with Dr. S. Kuby of the EnzymeInstitute, University of Wisconsin, Madison.

EUROPEAN Manufacturing Branch:C111son Medical Electronics (FRANCE)

X 9, Rue Gambetta - 95 - ViFliers-Leel, France

IN V\ !( )

-Nirclor- ofl Keciders Serveice Card

77=..:-40.l," :0.:1"'M.t--

f "I

If you have to service time-sharers

while running batch.

Get one Sigma.Most maclhines canln't lhandle both. A few fake it bytreating batclh like a time-sharing terminal, so itgets worked on a few milliseconds at a time.

Sigma 5 and 7 handle both, concurrently. Ournew BTM software allocates core memory andtime for effective batch time-sharing. But if allyour 38 time-slharer-s aren't time-slhai-ing, BTMautomatically takes up the slack to speed batclprocessing.

As a result, batch runs smootlhly at central site,or from remote batclh terminals. BTM even letstime-sharers have access to the batclh job streamfor greater computing power anid flexibility.

If batch i.sn't running fast enougah for you, ter-minal users can be garacefully dismissecd from the

system so all available time and memory can begiven to batch. Without stopping the system ordumping files just to change modes.

But just because Sigma uses half its mind forbatch and hialf for time-sharing, don't expect hialf-witted programs. There's a long list of conver-sational languages and services such as SDSBasic, Fortran IV H, and Symbol, which are com-patible for batch operations. Plus powerful batchprocessors like SDS Fortran IV, SDS Cobol 65,FMPS, SL- 1,Manage and others.

This sotIIuds like a promise oftlhingas to coImle. It isn't. We'll SOScoime to your office aind demoin- Scientific Data Systems,strate it. Now. El Segundo, California

Circle No. 32 on Reoders' Service Card910 SCIENCE, VOL. 164

I'll I I I II 1WvA

J

We've taken the fuss out of Electrophoresis.

No miore floppy str ips. Mylar backed acetatemakes strips firm, easy to handle.No miore pipetting. Nesw striper* uses capillaryaction to make sample take-up automatic.No miore variable applicationis. Built-in guideprovides in-chamber application. Sample posi-tion, quantity and alignment always the same.No mizore jury-rigging-no magnets, clips, tails,sponges or outriggers. Simply mount strips inprepositioned slots and stripe.No mnore fishing or finger dipping. Transfer

rack permits hands-off batch processinithrough entire cycle.No miore chemiical preparations. Just empty prepackaged containers into appropriate proceschamber.Our point of viev is that we've taken the fusout of the head-end of Electrophoresis. Try iand let us know your point of view.This head-end combined with our Densicord ia complete system and assures reproduciblresults regardless of operator fatigue.

'Patent applied I

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