..FluoresceinAntibody*Techniques

Fluoroscein Isothiocyanate (FIC) fluorescent antibodytechniques have proven valuable in the diagnosis of vari-ous communicable diseases, polio, rabies and typhoid,the identification of antigens, microorganisms and as aresearch tool in probing the mechanisms of antibodyformation and cytochemical studies on the distributionof homologous proteins in tissues and organs.

Previously, however, investigators usinig the fluorescentantibody technique have been annoyed witlh non-specificgreen fluorescence of certain tissue or with non-specificuptake of fluorescein conjugate.

Recently, a cotunterstaining procedure for use in con-junction with FIC lhas been reported by Hall and Hanson(1). This method utilizes aluminum chelates of dihydroxyazo dyes.Now, NBCo offers the entire group of azo dyes in

convenient kit form: (An assortment of 5 grams each ofthe listed counter stains for S6.25.)Flazo OrangeSuLperchrome Blue B ExtraDiamond Red ECB.- Extra Conc.Diamond Black

NUTRIBIOCHE.CORPCj 21010 Miles Ave.

24 DECEMBER 196-5

T

OFCle

Pontachrome Blue Black ZFPontachrome Violet SWAcid AlizarinFluorescent LabelingFor the convenience of laboratories desiring a completeinitial stock, NBCo offers an assortment of one each ofthe following biochemicals in 100 mg. ampuls at $12.50.5 Dimethyl Amiino-l Napthalenie Sulfonyl Chloride onCelite 10'1Fluorescein Isothiocvanate oni Celite 10%'Rhod.amine B Isothiocvanate on Celite 10%JoRosaminle B 4' lsothiocvanate on Celite 10%G}Fluorescein Amine (Fraction I or II)F'luorescein IsothiocyanateRhodamine B IsothiocyanateRosamine B 4' Isothiocvanate5 Dimethyl Amino-l-Naptlhalene-l Sulfonyl Cl (DNS)Phone collect, 216-662-0212 (U.S.A. only.) NBCo guar-

antees shipment withinl 60 minutes of your call, one-daydelivery anywhere in the continental U.S.A., 80 hoursanywhere in the world. Send for our free catalog con-taining more than 3000 items.

'IONAL /) As reported in Chem. & EngX News (Sept. 10, 1962). The litera-

* A Cture references should not be inter-

Lpreted as either an endorsement or)disapproval of the biochemicals by

2ATION tle cited investigator.-veland, Ohio 44128

1663

-ontrol and coninlLunicaitioni theory, wheth-cr in the machine or in the animal. h! thename CNvhcr/ctic.v, wlich w-e for-nii fl-omiithe Greek p,jiep'i-Tq1 0o .stt'ecElO/. Inchloosing this term, we wish to recognizethat the first significant paiperi on feed-bhackmelcianisms is an aIrticle on governors.hich was puiblisdleci hb Cler k Mavwell in868 [Proc Roy Soc. ( Loldon ) March 5.

1 868 I. and that ('o ,cr1Or is deri'.ed fr-omi aI atit com tipt ion of XrlepiE-q7T?7. We alsow ish to r-Cfel to the flCt that the steeni'rengines of a shlip ate indeed onie of theearliest aind best deeeloped tot ms of feed-

ackli imieclianislnis.

aI vn' writers. G-eek ats well asFrench. French as well as Itahlian. musth1.aV e uSCe the word, since it appear tobe a comimion '.ordimearn ning the steers-m.a n's art. and that phrase. while qUainttoday, muLst have been as comilmonly

C alling DLIco I)owo or Kodlak Ko(dakcalled tor milore imitgination and com-

mei-cial savvv and were genuIinelycoined, not merely borrowved. BLut whatdill'erence does it make'? WZortds after

ll II re, as Henrv Ward Bleecher salidl,'pegs to hang ideas oni." Antd \Wienerand his circle certainly succeecded indoing, that.

KI NNFt1 J. WVARD9 if() /rt/li Sherilda Roal.Ltlke For,t'c, IIlilioi.'

Looking Ahead

III .-t^i-OLing 'oi g;reater sLIpport of(gcrontologv. Rohert R. Kohni (ILetters.5 Nov.. p. 685) sav s. -'Aging processesarc . oft m11or1e personal concernto uIs thn. tfor example. mantle-drill-ing oor the sp.ace program...... Andrightl\ so.

According to a story popuilar- inGermany (East and West) duiring theI 950's, Gottwald was checking thebUdget one dayv, and the dillorg withhis advisers wenit aiboLIt a.s follows:

"Whait's this'? An addition of 1 00.-0)()0 marks for the grade schools'? No.

Denied. An addition of 500.000 imarksflo- the advanced schools? No. deniecd."

His advisers handed himl the nexthatch. and he continuLecd:

"An increase of 300.000i)mairks forpl.a grounds and parks'? No. Denied.

"Another 50)000() marks for li-braries?' No. No. No."Add 150(00() mairks for children's

hospitals and Iying-in homes? Denied."So it went. He cuIt every depart-

mental budcget uintil he came to theone for prisons.

"What's this'? No increase for pris-24 DECEMBER 1965

otis'? The samne budget as for last?ear? No. Doutble it' Allocate at least

a million marks for prison hospitals.librairies, and recreation centers. AnddouIhIC the operating buLdget."One of' hlis IaLdvisers renmonstrated.

"BLit Sil. N'OLI have cuIt all the otherinstitutiont s particulIkrlV the schools.Now whv do x'OuI increase the hUdgetsfor- the prisons'?"

Got twalId stared at hiiii mieLaningflIlysfor- aI minu11tLte. then explaiined. "We' e

been to school.''As the mniL sal s. wc can all expect

to be ag,ed. Shaill we stint the plansfor improiring thalt condlition?

F. C. DXI45)'9 C('urmberlmIr ,A cti,,c,

Messages from an Elder Scientist

In his article on the developmiientof the chenriistrr of solution.s ( "Orterfroml chaos." 22 Oct.. p. 441 ) JoelHildebrand delineates the clifference he-tween a trtLe scientist andi a niere prac-titionier. The one has schoolecd himiiself'to underst.and: the other has devotedhis academic life to learning all therecipes. He-e is anmessace so vital to

a beginning scientist that he hardlyrdare disregard it.The airticle carries also. bv exariiple

rather thlan precept, a niessage abLouteflective coriinLinicatiori aimonig scien-tists. It is replete with exiimples of coiii-niunication at its best. Consider thisstatement froiii his discuIssion of scien-tific prediction: "The odds are ex-trernelv high for predicting an eclipse,

. near zero for the tilile when JohnDoe will die." He nii-ht have writtenit this way: "Prediction of an eclipsecan be acconiplished with an extrenielvhigh degree of acCuracv. bLIt it shoLitdbe noted that the probability factorchanges considerably in the case ofpredicting the time at which life ceasesfor a hUmran being." NattUrally, thenee tfor izood coniniunication becoiiiesnLich niore iniperative when ain elderscietitist is trying to teach a Vouingerone. The stulfied-shirt approach to sci-ence writing never itispired .anvone. Yethow manyN elder scientists continuIe toexpo ind their ideas in a writing st'sielike thaLt of' a mlaster's thesis.

WARD W. KONK;l.AgriCLIltUral Science Review,U.S. lJepairtl)1e(1t of A gricldtitre.Wad/tii-toli. D.C. 20250

pH electrode

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I667

Extending the capabilities of research equipmentThe Tandem Research Group has made notableprogress in the past year. Significant experimentalresults from the program are:

1. 250 mA high-brightness positive ion beam froman expanded-plasma source operating at 38 kv,

2. 270 ,A analyzed beam of H,-- ions out of theResearch Tandem with 320 pA H injection andwater-vapor stripping.3. 2.0 aA analyzed dc beam of He ions. The pre-vious maximum current routinely available hasbeen 0.1 8LA with the EN source.

Doubly Charged Components are now available for converting 3, 4 and nitrogen have also been produced with the newHelium Ions and 5 MeV machines to produce He' ions at higher kit installed in a 3 MeV Van de Graaff. Beam ener-

energies. Specifications: 30..A at 5.0 MeV; 10 aA gies from 5.04 MeV to 9.8 MeV and beam currentsat 7.0 MeV; 5 aA at 10.3 MeV. More than double from 0.1 to 10 1A were observed. For details on thethis current performance has been demonstrated new HE kit and experimental results, write forbut with some loss in stability and reliability. Technic<l Note 13.Multiple-charge states (2, 3 and 4) of neon, oxygen

Optical When arn energetic beam of Ions is passed throughSpectroscopy of a thin foil, the charge state of the ion may change,Excited Atomic either up or down. The emitted particles may beleft in states of electronic excitation from which

States visible light is subsequently emitted during de-excitation. The emitted light spectrum is charac-teristic of the excited ion. When particle beams ofapproximately 0.4 JA or more are used, the lightis sufficiently intense for spectroscopic analysis.

The refinement and application of this techniquepromises to be of major importance in the theory ofatomic structure, in measuring hot plasma tempera-tures, and in acting for the means of energy loss in

fastfsinfa m nsi ana sre. Pehp mosA riltrogen beam, 0.8 ,A at 2 MeV, passes from right tofast fission fragments in an absorber. Perhaps most L

importantly, it will help determine the relative left through a carbon foil approximately 9,,g/cm2 th:ck.abundance of the elements in the sun and other of astronomical objects and the nature of thestars, which is the basis for theory of stellar evolu- stellar energy. For further details, ask for Tech-tion, the origin of the chemical elements, the age nical Note -10.

Intense Ion The ICT-500 keV positive ion accelerator now beingBeams at 500 kv built by High Voltage Engineering operates at ener-

gies from 100 to 500 keV dc and pulsed. In per-formance tests, the machine has produced analyzedion beam currents from 4 mA at 100 keV to 10 mAfrom 300 to 500 keV. 10 mA dc positive ion beamcurrents of HI, H2, and DI have been produced at atarget located 6 feet from the end of the accelera-tion tube. Beam diameter is 15 millimeters maxi-mum for all particles over the entire energy range.Previous experience with a similar machine of 300keV maximum energy showed 15 mA of d2 anda 3 centimeter beam diameter. The ICT 500 posi-tive ion accelerator is designed for dc and pulsed\operation in the nanosecond and microsecondrange with a minimum pulse length of 2 nsec. ata repetition rate of 2.5 Mc s. Puilse content is 1 mAprotons and 0.7 mA deutrons. 4

The high-brightness, intense ion beam produced byThe particle source utilized with the ICT-500 po- the ICT-500 accelerator is eminently suited fortive ion accelerator is an expanded plasma type laboratory production of 14 MeV neutrons for cross-which has produced 70 mA total beam at 500 kv. section measurements dosimetry studies weapons

effect simulation and special low-density targetexperiments.

For detailed information, write to Technical Sales, High Voltage EngineeringCorp., Burlington, Mass. or HVE (Europa) N. V. Amersfoort, The Netherlands.Subsidiaries: Electronized Chemicals Corporation, Ion Physics Corporation.ARC(D Division, Walnut Creek, California.

I(.68

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