I VIBRATIONISOLATIONTABLES

Whether you realize it or not, the per-formance of sensitive instruments isadversely affected by vibration. Photo-micrography, metrology, holography,laser equipment and micromeasuringdevices, are but a few of the areaswhich demand a far steadier environ-ment than is available in most instal-lations. Don't blame the instrument or

its operator for errors.0 Check intoEPOI's anti-vibration system. Its revo-lutionary design isolates 90-98% ofthe environmental vibrations. Call orwrite for our brochure--the facts maysurprise you.Nikon Inc., a division of Ehrenreich Photo-Optical Industries, Inc., 623 Stew-art Ave., Garden City, N.Y. 11530 r(516) 248-5200. Telex: 967806 a

arthropods, although interesting initialstudies on an apparent genetic variabil-ity in responses of mouse strains tothe louse Polyplax were presented bythe staff of the Rocky Mountain Labo-ratory.The immune response of guinea pigs

to the cat flea (Ctenocephalides felis)has provided a basis for understandingthe responses to other blood-suckingarthropods with a discrete period of hostcontact; examples are mosquitoes, blackflies, and biting midges. The response,which progresses from initial nonre-activity through delayed dermal hyper-sensitivity to immediate hypersensitiv-ity and finally to nonreactivity, ismediated by a hapten of low molecularweight, which requires conjugation withskin collagen before it becomes im-munogenic. Each phase of the hostreaction may influence the ability of anarthropod-transmitted pathogen to be-come established. Thus, in a delayedhypersensitivity response to flea salivaryhapten, the mononuclear cell infiltratemay provide a milieu that favorsgrowth of the plague bacillus. In animmediate response, scratching and rub-bing induced by pruritis may assistentry of disease agents, as in Chagasdisease, or microvascular dilation maypermit easier access for organisms tothe systemic circulation.

In the case of arthropods with long-term host contact, such as ticks, hostresponses directly or indirectly rejectthe vector, although the mechanismsare poorly understood. Notwithstand-ing, these responses are important indisease transmission, especially withagents (for instance, Babesia and Thei-leria) that proliferate and reach theinfective stage in the salivary glandsduring engorgement of the tick. Withimmune hosts, the stage of tick devel-opment required for disease transmis-sion may not be reached.

Discussion of such topics identifiedfuture research areas with public healthimportance. With respect to the arthro-pod, study is needed of genetic variabil-ity in vector capacity. Techniques suchas isoenzyme analysis were suggestedto measure population heterozygosity inspecies in which conventional geneticanalysis is not feasible. A closer studyof arboviruses in mosquitoes (for exam-ple, genetic variation in the response ofAedes triserialis to the agent causingCalifornia encephalitis) or studies ofPlasmodiurn species in Anopheles wouldbe profitable. Greater emphasis is re-quired on tick physiology, especially theneurosecretory and hermonal systems.

o- 1t

P I TT S BU R G H* LO N Do N * F RA N K F U RT

Circle No. 83 on Reader's Service Card

CYTO LOG ISTS:now prepare more slidesin less time, with less fluid

The Shandon Cyto-Centrifuge employs aunique cell concentrating and distributingtechnique permitting you to prepare alarge quantity of microscope slides usinga smaller amount of human blood plasma,synovial fluid, peritoneal exudates, semi-nal or other body fluids. Centrifugation and slide preparation are per-formed simultaneously, which eliminates prior centrifugation and savesyou time. Improved head design ensures safety when working withpathogenic organisms.

The Shandon Cyto-Centrifuge produces a monolayer of cells and doesnot damage individual cell structure. Also, processed slides can berapidly scanned using a preset high power objective without adjust-ment between slides. Get the full story on the Cyto-Centrifuge and otherquality scientific tools . . . write Shandon Southern Instruments, Inc.,515 Broad Street, Sewickley, Pa. 15143 (Pittsburgh District).

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1154 Circle No. 81 on Readers' Service Card SCIENCE, VOL. 176

A special need is the isolation andchemical and neurophysiological char-acterization of tick toxin. With respectto the host's response to arthropodbites, delineation of the classes and sub-classes of immunoglobulins in the im-mediate hypersensitivity reactions is re-quired, as is the differentiation betweendelayed, cell-mediated hypersensitivityand basophil cell responses. Oral secre-tions of arthropods need to be isolatedand characterized immunologically andpharmacologically. A closer study ofthe cell types and tissue reactions at thebite site is required and physiologicalstudies of the microvascular changesat this site and the adjacent area arewarranted.

Such research would add to an un-derstanding of the infection process insystems of arthropod vector, parasite,and host. Novel measures for diseasecontrol might result through, for ex-ample, desensitization of hosts to ar-thropod bites, immunization againstticks or mites, and genetic manipulationof vectors. Multidisciplinary approachesare needed to these research problemsthrough active collaboration of differ-ent scientists, especially of entomolo-gists, insect physiologists, biochemists,geneticists, immunologists, microbiolo-gists, or parasitologists. In view of themany unexplained significant differ-ences in annual and regional occur-rences of vector-borne infections, sev-eral systems of host, vector, and infec-tious agent require attention and re-search.

E. J. L. SOULSBYWILLIAM R. HARVEY

School of Veterinary Medicine,University of Pennsylvania,Philadelphia 19104, andDepartnment of Biology, TempleUniversity, Philadelphia 19122

Spontaneously Hypertensive Rat

A seminar on the spontaneously hy-pertensive rat was sponsored jointly bythe National Science Foundation andthe Japanese Society for Promotion ofScience. The seminar was held in Kyoto,Japan, from 18 to 22 October 1971.In addition to the participants fromJapan and the United States, the semi-nar was also attended by observers fromCzechoslovakia, New Zealand, Sweden,Switzerland, Yugoslavia, and West Ger-many.

Genetic strains of hypertensive ani-mals offer certain advantages as experi-9 JUNE 1972

The simple,sure-shot

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eliminating guesswork. Readings provide accurate, fail-proof exposuresettings that make picture taking through the microscope a snap.

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amplifier produces undistorted images that are the identical shape ofyour specimen. Compare it to any other system you've ever used and see

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Circle No. 43 on Readers' Service Card llSS

mental models of hypertension, as thehypertension develops without the in-tervention of either surgery or othermanipulatory practices. By selectivebreeding, a colony of spontaneously hy-pertensive rats was developed in thelaboratory of Professor Kozo Okamoto,Department of Pathology, Kyoto Uni-versity, School of Medicine, Kyoto,Japan. With the cooperation of Pro-fessor Okamoto, a colony was estab-lished at the National Institutes ofHealth in 1966, under the supervisionof Dr. Carl Hansen. From that initialcolony in Bethesda, Maryland, therenow exist some 40 groups throughoutthe United States that have establishedcolonies of these hypertensive rats.Colonies exist in many other countriesas well.The basic questions posed at the

seminar concerned the pathogenesis ofthe hypertension in these animails andthe questions of whether the progres-sive hypertension that is seen with in-creasing age and the course of histo-pathology that ensues is similar to thatof essential hypertension in man. Alarge proportion of the papers and dis-cussion was centered on the sympatheticnervous system and the renin-angio-tension system to determine whetherthey were implicated in the hyperten-sion. A number of groups reportedthat, if anything, these systems exhibitedreduced activity as a compensatorymechanism for the hypertension. Thus,the spontaneously hypertensive rat ap-pears to be an excellent model of hu-man essential hypertension in that thehypertension has a hereditary compo-nent, and does not appear to ibe ofprimary renal or simple neurogenicorigin.

Studies were also reported on theuse of these animals to evaluate thetherapeutic efficacy of antihypertensiveagents. Despite the availability of manyanimal models to evaluate hypotensivedrugs, the action of many of the com-monly used antihypertensive,drugs werefirst observed in man. In general, itwas found that the spontaneously hy-pertensive rat appears to be a sensitiveexperimental model for evaluating anti-hypertensive drugs. Studies on two newand interesting drugs, fusaric acid andoudenone, were presented.

Another point repeatedly brought outwas that the sequelae of the hyperten-sion in the spontaneously hypertensiverat resemble those seen in essentialhypertension. These include the cerebraldamage, arteriosclerosis, and cardiachypertrophy. These changes did not oc-cur in animals in which the pressure was

Circle No. 82 on Readers' Service Card

kept from rising by treatment withantihypertensive drugs.

These animals offer an opportunityto answer critical questions in regardto the problem of huuman essential hy-pertension. Furthermore, the fact thatthey are now generally available makesit possiible to compare the results ofinvestigators in different laboratories.

SIDNEY UDENFRIENDSYDNEY SPECTOR

Roche Institute of Molecular Biology,Nutley, New Jersey 07110

Forthcoming Events

July

1-7. International Assoc. of MedicalLabs., 10th congr., Vienna, Austria.(Mrs. I. Hertz, Verband dipl und technAssistentinnen, Spitalgasse 4, 1090 Vienna)

2-5. Environmental Acoustics, 2ndsymp., London, England. (Meetings Of-ficer, Inst. of Physics, 47 Belgrave Sq.,London SWIX 8QX)

2-6. International Congr. of PhysicalMedicine, 6th, Barcelona, Spain. (J. S.Garcia Alsina, IFPM, Ravella 4, Barce-lona 6)

2-7. Environment, 36th annual conf.,Natl. Environmental Health Assoc., NewYork, N.Y. (N. Pohlit, NEHA, 1600Pennsylvania Ave., Denver, Colo. 80203)

3-6. Shell Structures and Climatic In-fluences, Intern. Assoc. for Shell Struc-tures, Calgary, Alta., Canada. (P. G.Glcckner, Dept. of Civil Engineering,Univ. of Calgary, Calgary 44)

5-8. Shock Tube Symp., 8th intern.,London, England. (Symp. Secretary, Dept.of Aeronautics, Imperial College, PrinceConsort Rd., London, S.W. 7)

6-8. RF Plasma Heating, AmericanPhysical Soc., Lubbock Tex. (M. 0. Hag-ler, Dept. of Electrical Engineering, TexasTech Univ., Lubbock 79409)

9-12. Molecular Beams, 4th intern.symp., Cannes, France. (F. M. Devienne,Laboratoire de Physique Moleculaire desHautes Energies, B.P.2 (06), Peymeinade,France)

9-14. American Malacological Union,Galveston, Tex. (A. S. Merrill, BiologicalLab., Natl. Marine Fisheries Service, Ox-ford, Md. 21654)

9-14. Power Engineering Soc., SanFrancisco, Calif. (Meetings Officer, Inst.of Electrical and Electronics Engineers,Inc., 345 E. 47 St., New York 10017)

9-14. Public Transportation in UrbanAreas, Engineering Foundation, Henniker,N.H. (EF, 345 E. 47 St., New York10017)

10-12. DNA Synthesis in vitro, 2ndannual Steenbock symp., Madison, Wis.(Mrs. M. Parker, Dept. of Biochemistry,420 Henry Mall, Univ. of Wisconsin,Madison 53706)

10-14. Coastal Engineering, intern.conf., American Soc. of Civil Engineers,Vancouver, B.C., Canada. (H. R. Hands,ASCE, 345 E. 47 St., New York 10017)

SCIENCE, VOL. 176

superior convenience,reliability and versatility tomeet the precise needs orthe life science researcher

Packard's 7400 Series Gas Chromatographs offer exceptional Aflexibility to permit the selection of an instrument tailored to yourspecific research application. Sensitive enough for analyses atpicrogram levels, yet fully capable of preparative separations,the 7400's are designed for maximum reliability and operator

convenience. Computer circuitry controls the automatic door forrapid oven cooling and precise equilibration at the digitally

set initial temperature-only one of the many exclusive features.Both analog and digital temperature programmers are available.

Write for complete information-request Bulletin 1058D.

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Circle No. 61 on Readers' Service Card

Thepurewatermachine.Introducing Aquella,TMCarborundum's simple way ofproducing ultrapure water that'svirus-free.The Carborundum water-purificationappliance, developed initially fortissue culture research with thetechnological assistance of BaylorCollege of Medicine, is now availablefor use in hospitals and clinicallaboratories-pharmaceutical,electronic, and industrial applications.

Requiring minimal maintenance,the self-contained unit can bequickly transported and installed toprovide a source of biopure water.A series of unique depth filters

in combination with reverse osmosis,ion exchange, and ultrafinemembrane filtration

9 JUNE 1972

produces a virus-free outputwater which exceeds 8megohmcentimeters in aproperly operated andmaintained unit.Send the coupon now and

learn all the facts.TAAquella is a trademark ofThe Carborundum Company

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* X:- ;: FREE¢* e TRIAL

See for yourself why Holtzman Rats are specifiedby more laboratories each year. They're the resultof modern techniques in caesarian derivation, par-tial inbreeding, nutrition and animal husbandry.All Holtzman Rats are air-shipped in close weightand age groups. Safe arrival and satisfactory qual-ity guaranteed. Extra rats included in every orderFor your free trial supply, just fill out and mailcoupon. Let us prove what we say.

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i Circle No. 103 on Readers Service Cord

KLETT-SUMMERSON TEST KIT

For more information, request Bulletin A-206

The LAB APPARATUS Co.18901 Cranwood Parkway * Cleveland, Ohio 44128 U.S.A.

Formerly a Division of The Chemical Rubber Co.

Circle No. 101 on Readers' Service Card

Product Newsfrom Amersham/Searle

AN IODINE-125 THAT ALWAYSIODINATES PROTEINS EFFICIENTLY.Iodine-125, from Amersham/Searle, is the highestquality and the most reliable available for labellingof proteins, and will always efficiently iodinate pro-teins. Improvements in the production, isolation,and purification have produced this new high levelof performance and new lower prices.IODINE-125Iodide, carrier free, in NaOH so-lution, pH8-1 1 free from reduc-ing agent, contains <1% "26I80-140mCi/ml for protein iodi-nation. Packaging: 'Microflex'vials.

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10-14. Interaction of Radioactive Coit-taminents with the Constituents of theMarine Envronment, Seattle, Wash. (J.H. Kane, Div. of Technical Information,U.S. Atomic Energy Commission, Wash-ington, D.C. 20545)

10-14. Rarefied Gas Dynamics, 8thintern. symp., Stanford, Calif. (K. Ka-ramcheti, Dept. of Aeronautics and Astro-nautics, Stanford Univ., Stanford 94305)

11-14. Society of Nuclear Medicine,Boston, Mass. (Mrs. M. Glos, SNM, 211E. 43 St., New York 10017)

11-15. National Soc. of ProfessionalEngineers, Denver, Colo. (P. H. Robbins,NSPE, 2029 K St., NW, Washington, D.C.20006)

12-15. International Soc. of ClinicalLab. Technologists, St. Louis, Mo. (D.Bier Birenbaum, ISCLT, 805 AmbassadorBldg., St. Louis, Mo. 63101)

16-19. American Assoc. for ClinicalImmunology and Allergy, Seattle, Wash.(S. H. Jaros, AACIA, 9705 Louis Dr.,Omaha, Neb. 68114)

16-20. American Veterinary MedicalAssoc., New Orleans, La. (M. R. Clarkson,AVMZ, 600 S. Michigan Ave., Chicago,Ill. 60605)

16-21. International Soc. of Hemta-tology, intern. congr., Saio Paulo, Brazil.(World Federation of Hemophilia, Suite806, 1420 St. Mattieu, Montreal 108, P.Q.,Canada)

16-28. Technology and the People, Inst.on Man and Science, Rensselaerville, N.Y.(G. A. Enk, IMS, Rensselaerville 12147)

17-20. International Symp. on SexEducation. Tel Aviv, Israel. (E. Chigier,P.O. Box 16271, Tel Aviv, Israel)

17-21. Electron Probe Analysis Soc. ofAmerica, 7th natl. conf., San Francisco,Calif. (C. G. Cleaver, General ElectricCo., Vallecitos Nuclear Center, Bldg. 105,Pleasanton, Calif. 94566)

17-22. American Medical Technolo-gists, Philadelphia, Pa. (C. B. Dziekonski,AMT, 710 Higgins Rd., Park Ridge, Ill.60068)

18-21. Cyclotron Conf., 6th intern.,Vancouver, B.C., Canada. (N. Brearley,Univ. of British Columbia. Vancouver 8)

18-21. Hormones, the Brain, and Be-havior, 3rd intern. symp., Intern. Soc. ofPsychoneuroendocrinology, London, Eng-land. (R. P. Michael, Inst. of Psychiatry,De Crespigny Park, Denmark Hill, Lon-don SE5 8AF)

19-21. Defects in Semiconductors, in-tern. conf., Reading, England. (MeetingsOfficer, Inst. of Physics, 47 Belgrave Sq.,London S.W.1, England)

19-22. Calorimetry Conf., 27th, ParkCity, Utah. (J. M. Sturtevant, Dept. ofChemistry, Yale Univ., New Haven, Conn.06520)

20-22. Modern Instrumental Methodsin Natural Products Research, AmericanSoc. of Pharmacognosy, Columbus, Ohio.(J. E. Robbers, School of Pharmacy andPharmacal Science, Purdue Univ., Lafay-ette, Ind. 47907)

23-28. Control Strategies for PowerSystems, Engineering Foundation, SouthBerwick, Maine. (EF, 345 E. 47 St., NewYork 10017)

23-28. Illuminating Engineering Soc.,Tulsa, Okla. (P. C. Ringgold, IES, 345E. 47 St., New York 10017)9 JUNE 1972

23-28. Pharmacology and the Futureof Man, 5th intern. congr., AmericanSoc. for Pharmacology and ExperimentalTherapeutics, San Francisco, Calif. (E. B.Cook, ASPET, 9650 Rockville Pike,Bethesda, Md. 20014)

24-29. Foetal and Neonatal Physiology,Sir Joseph Barcroft Centenary Symp.,Physiological Soc., Cambridge, England.(P. W. Nathanielsz, SJBCS, PhysiologicalLab., Cambridge, England)

24-30. Angiology, 8th intern. congr.,Rio de Janeiro, Brazil. (D. F. M. Bunce,Dept. of Physiology, College of Osteo-pathic Medicine and Surgery, Sixth atCenter, Des Moines, Iowa 50309)

26-29. American Dairy Science As-soc., Blacksburg, Va. (C. Cruse, ADSA,425 Illinois Bldg., 113 N. Neil St.,Champaign, Ill. 61820)

26--31. Inter-American Meeting ofNeuroradiology, Rio de Janeiro, Brazil.(A. Tomax Rezende, Caixa Postal 9031,ZC-02, Rio de Janeiro, Gb)

27-29. Extra-Corporeal Technology,10th intern. conf., New York, N.Y. (E. C.Berger, American Soc. of Extra-CorporealTechnology, Inc., 287 E. 6 St., St. Paul,Minn. 55101)

27-29. Intracranial Pressure, 1st intern.symp., Hannover, Germany. (M. Brock,Neurochirurgische Klinik, MedizinischeHcchschule Hannover, 3 Hannover-Klee-feld, Roderbruchstrasse 101, Germany)

29-5. Technology and Human Future,19th annual, Inst. on Religion in an Ageof Science, Star Island, N.H. (F. Nesbett,219 Harvard St., Brookline, Mass. 02146)

30-2. American Soc. of Animal Science,Blacksburg, Va. (G. P. Lofgreen, Im-perial Valley Field Sta., 1004 E. HoltonRd., El Centro, Calif. 92243)

30-3. Crystal Growth, 2nd natl. conf.,American Assoc. for Crystal Growth,Princeton, N.J. (D. Richman, RCA Labs.,David Sarncff Research Center, Princetoni,08540)

30-3. Society for Cryobiology, 9th an-nual, Washington, D.C. (D. M. Robinson,Red Cross Blood Research Lab., 9312 OldGeorgetown Rd., Bethesda, Md. 20014)

30-3. National Dental Assoc., NewOrleans, La. (NDA, P.O. Box 197, Char-lottesville, Va. 22902)

30-4. International Organization forMedical Physics, 3rd, Goteborg, Sweden.(R. Kadefors, Dept. of Applied Electron-ics, Chalmers Univ. of Technology, 40220 Goteborg)

31-4. Emergency Medical Services,American Paramedical Inst., Honolulu,Hawaii. (J. Galbreth, API, P.O. Box4496, Honolulu 96813)

31-4. Use of Nuclear Techniques inthe Basic Metal Industries, Intern. AtomicEnergy Agency, Helsinki, Finland. (J. H.Kane, Div. of Technical Information,Atomic Energy Commission, Washington,D.C. 20545)

August

2-4. Applications of X-ray Analysis,21st conf., Denver, Colo. (C. 0. Ruud,Metallurgy and Materials Science Div.,Denver Research Inst., Univ. of Denver,Denver 80210)

4-7. Poultry Science Assoc., Columbus,Ohio. (C. B. Ryan, Texas A&M Univ.,College Station 77843)

IOnRCliniFugeeVernitron enters the lab with Lourdes ModellOR Clini-fuge.Now there's no need to sacrifice quality foreconomy.The refrigerated 1OR Clini-fuge com-bines both. With features like 4 litre capacity...horizontal...angle...continuous flow system atspeeds to 5,000 RPM; optional high speed at-tachment to 17,500 RPM. An autotransformerfor accurate speed control. A temperature con-troller. Refrigeration and centrifuge masterswitches with pilot lights plus an electro-dynam-ic brake switch. 0-120 minute timer with auto-matic "hold" position. Continuous readingelectric tachometer. Heavy steel plate to pro-tect your operator. Easy-reach control panelfor all instrumentation.To bring Vernitron into your laboratory, writefor our clinical laboratory literature or contactyour local dealer...today. And you, too, willpraise the Lourdes.

r Vernitron Medical Products, Inc.Empire Blvd. & Terminal Lane, Carlstadt, N.J. 07072

Circle No. 80 on Readers' Service Card

1159

46F

ANVA

4

A digital approachSingle-photon counting, a highly sensi-tive technique which actually samplesindividual quanta of light, is generallyacknowledged to be the best method ofmeasuring very low light levels. NowOrtec has applied this technique to thefield of nanosecond flIjorescence spec-troscopy. The Ortec Model 9200 Nano-second Fluorescence Spectrometer usesa short duration optical light pulse to

excite the sample and measures thedecaying fluorescence intensity as a

function of time over several decades.Our system offers sensitivity and accu-

racy increased by orders of magnitudecompared to existing analytical tech-niques. This new system is alreadyproducing outstanding results in studiesof chemical reaction rates, molecularstructure, and molecular conformationchanges.

Improved data reductionA multichannel analyzer records eachdetected fluorescence photon against a

time base for immediate CRT display or

Teletype printout of the spectrum. Datais manipulated and stored in a digital,

computer-compatible mode. A computerinterface can thus be incorporated tofacilitate reduction of complex data.The 9200 system will measure both

single and multiple decay components.Multiple components are clearly repre-sented on the spectrum and easily read.(The spectrum above shows the straightline response of a sample having a singlelifetime.)

Sensitivity is better than 1 ppb quininesulfate in sulfuric acid. Linearity is typ-ically better than 1%.

System componentsThe exact system configuration will de-pend on the user's particular require-ments, but the basic system consistsof a nanosecond light pulser, samplechamber including photomultiplier, multi-channel analyzer, and associated elec-tronics. The entire system is designedaround NIM-standard modules for en-hanced flexibility, reliability, and easeof servicing.

Data sheet on requestIf you'd like more information on theOrtec Model 9200 Nanosecond Fluore-scence Spectrometer, we'd be happy tosend you a data sheet that tells all aboutit. Just write or call Ortec Incorporated,110 Midland Road, Oak Ridge. Tern.37830. Phone: (615) 482-4411.

In Europe: Ortec Ltd., Dallow Road, Luton,Bedfordshire. Phone: LUton 27557. Ortec GmbH,8 Munchen 13, Frankfurter Ring 81, West Ger-many. Phone: (0811) 359-1001.

EG G ri J

Circle No. 42 on Readers' Service Card

a

04011

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t

ltt

13 18. Engineers' Role in Today's So-ciet Engineer ing FoLind.ition, Hennikec-,N.H. (EF Confs.. United EngineeringCenter. 345 F. 47 St.. Ncs Yorki 10017)

1-/ 18. Improvinig Inidoor Alir Quality.SCIt-'NF.'E, V01 t17

6-9. Soil Conservationi Soc. of America,Poi-tland, Ore. (H. W. Pritchard, 7515NE Ankeny Rd., Ankeny, Iowa 50021)

6-10. Americ.an Phytopathological Soc..NMexico City, Mexico. (R. J. Green, Jr..Dept. of Botany and Plant Pathology,PuLrduLe Univ., Lafayette, Ind. 47907)

7-9. Anatomic Pathology of Fish, Reg-istry of Comparative Palthology and Univ.of Wisconsin Sea Grant Program, Wash-ington, D.C. (G. Migaki, CompairativeP,athology Branch, Armed Forces Inst. ofPathology, Washington. D.C. 20395)

7-9. Atmospheric Radiation, AmericanMleteorologicail Soc., Fort Collins, Colo.ANIS. 45 Beacon St., Boston, Mass.)7-10. Amer-ican Health Congr., jointly

by American Hospital Assoc., CatholicHospital Assoc., American Nuirsing HomeAssoc., and Health Indutstries Assoc.,Chicago, Ill. (G. F. SchuLyler, AHC, 840N. Lake Shore Dr., Chicago 60611)

7-I1. Atomic Physics, 3rd intern. conf..Boulder, Colo. (S. J. Smith, Joint Inst.for Lalb. Astrophysics, Univ. of Colorado.Boulder 8t)302)7- 11. Engineering in Mlediciine-Auto-

iniatic Cytology. Fngineering Foundation,Saxtons River, Vt. (FF Confs., UnitedEngineering Center, 345 E. 47 St., NesA'or-k 10017)7- 11. Fundamenitals of Transport Phe-

tioomenia in Porous NMedia, 2nd syimip., In-tern. Assoc. for Hydraulic Research andIntern. Soc. of Soil Science, Guelph, Ont.,Canadal. (D. E. Elrick, Dept. of SoilScicuelk. Univ. (f (Ctielph, (GLclph)

7- 14. Biophysics Congr., 4th intern.,Iinterni. Union for PuLre and Applied Bio-physics. Moscosw, U.S.S.R. ( L. P. Kayu-shill. I'1ofsoyL1zna'tya 7, Moscow)

9 I I Cry ogenic Enginieeriing Conf..Bioullder. Colo. ( L. K. Arimstrong. Nal-tjional BUr e.au. of Sttndirds, Boulder-

03(-) (-)211. Reindeer/Caribou S 11p.. 1st in1-

terl a.. Inst. of Arctic Biology alnd AlaskaC ooperative Wildlife Research Unit, FIair-banks, Alaska. (R. G. White, IAB. Unix.of A\lalka. Fairbanks 99701 )

10-17. International Geographical Un-ion., 2nd intern. congr.. Montreal. P.Q..C anadla. (I. K. Frt ser. IGU. P.O. Box972, (Otta ,. Ont., Clanada

1- /3. Mlarine Technology Soc., Wash-inulton. D.C. (R. W. Niblock, NITS, Suite412, 17'() MX St.. NW, Washington, D.C.20 0) 6 )

12. Amierican Soc. of Naturalists. NliM -

icapolis. Nlinn. ( Miss J. B. Spofford.Dept. of Biology, Univ. of Chicago.C hicaielo. I11. 60637)

/ -- 17. Biology of the Seal, intcrn.sxnmp.. Intcrn. Couincil foi the Explorationof thc Seca Intern. Commission for thcNorth est Atlalntic Fisheries, ,indl Intern.13ii(,I(ical Progri n1nmc. (LCIlph. Ollt..C .lnadtal. ( K. Ronald. College of Biolog-hiil Sciences. Univ. of Giic'lph. Ctielph.Ofnt.)

/3 -17. Bionietric Soc.. Eastern NorthAmeri can Region. NMontreal. P.Q.. Canad;a.(IF. B. Calidy, Biomletric Unit, 337 WarrenIt-kll. Cornell Univ., Ithaca, N.Y. 14850)

Engineering Foundation, South Berwick,Maine. (EF Confs., United EngineeringCenter, 345 E. 47 St., New York 10017)

13-19. International Congr. of Psy-chology, 20th, Tokyo, Japan. (ScienceCouncil of Japan, 22-34 Roppongi 7chome Minato-ku, Tokyo 106)

14-16. Association for ComputingMachinery, Boston, Mass. (C. Giltner,Lincoln Lab., Massachusetts Inst. of Tech-nology, P.O. Box 73, Lexington 02173)

14-17. Biometric Soc., Western NorthAmerican Region, Montreal, P.Q., Canada(J. W. Kuzma, Dept. of Biostatistics, LomaLinda Univ., Loma Linda, Calif. 92354)

14-17. American Statistical Assoc.,Montreal, P.Q., Canada. (J. W. Lehman,ASA, 806 15th St., NW, Washington,D.C. 20005)

14-18. Australian and New ZealandAssoc. for the Advancement of Science,44th cong., Sydney, Australia. (Mrs. D.Stretton, Dept. of Physiology, Univ. ofQueensland, St. Lucia 4067, Brisbane,Australia)

14-18. Symposium on Cosmochemistry,Intern. Assoc. of Geochemistry andCosmochemistry, Cambridge, Mass. (A.G. W. Cameron, Belfer Graduate Schoolof Science, Yeshiva Univ., AmsterdamAve. and 186 St., New York 10033)

14-18. American Ornithologists' Union,Grand Forks, N.D. (R. C. Banks, Birdand Mammal Labs., National Museum ofNatural History, Washington, D.C. 20560)

14-18. Physics and Chemistry of Ice,intern. symp., Royal Soc. of Canada, Ot-tawa, Ont., Canada. (M. K. Ward, Na-tional Research Council, Ottawa KIAOR6)

14-18. Social Science and Medicine, 3rdintern. conf., Elsinore, Denmark. (P. J.M. McEwan, Center for Social Research,Univ. of Sussex, Falmer, Brighton, BN I9QN, Sussex, England)

15-17. Science and Policy in the North,23rd Alaska science conf., Alaska Div.,American Assoc. for the Advancement ofScience, Fairbanks. (G. S. Harrison, Inst.of Social, Economic and Government Re-search, Univ. of Alaska, College 99701)

15-17. Society for the Study of Amphib-ians and Reptiles (15th annual) andHerpetologists League, Lake Texoma,Okla. (V. H. Hutchinson, Dept. ofZoology, Univ. of Oklahoma, Norman73069)

15-18. American Astronomical Soc.,East Lansing, Mich. (H. M. Gurin, AAS,211 FitzRandolph Rd., Princeton, N.J.08540)

15-18. Primatology, 4th intern. congr.,Intern. Primatological Soc., Portland, Ore.(W. Montagna, Oregon Regional PrimateResearch Center, 505 NW 185 Ave.,Beaverton 97005)

15-25. International Cartographic As-soc., 4th general assembly, Montreal,P.Q., Canada. (B. Timmermans, PublicRelations and Information Services, Dept.of Energy, Mines, and Resources, Ottawa,Ont., Canada)

16-18. Radiationless Processes in Gas-Phase Molecules, intern. conf., Boulder,Colo. (W. C. Lineberger, Joint Inst. forLaboratory Astrophysics, Univ. of Colo-rado, Boulder 80302)

16-19. Strontium Metabolism, 2nd in-tern. conf., Glasgow, Scotland. (J. M. A.9 JUNE 1972

W- -[s-- z

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make sure you lookinto this M-7 ZoomStereomicroscope.1

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Molecular weight!Molecular weight estimations by Nakos and Mortenson1.) Bio-Rad

gBio-Rad's SDS- offers highly purified and testedusing reagents for SDS-acryla-Acrylamide Gel mida gel electropho-0Electrophoresis resis: acrylamide,Bis, SDS, TEMED,Rapid and accurate A-am m o n i u mpolypeptide mo- -p e r s u I f a t elecular weight 2-mercapto-estimationscan ethanol andbe achieved Coomassie-with the SDS- -5 brilliant blueacrylamide -R-250. Pur-gel electro- chase themphoresis singly or intechnique. the SDSThe key is a Acrylamidepotent pro- Kit which-tein denatur- c o n t a i n sant and solu- representa-bilizing agent, tive quantitiesSDS (sodium 'tof each rea-dodecyl sulfate) - gent. Like toIt binds to pro- know more abotteins to cancel dif Bio-Rad's prod-ferences in intrinsic . .- ucts for gel elec-charge and converts 0 trophoresis? Write fortheir shape to rod-like Price List X with sixparticles whose lengths pages devoted to reagents,vary uniquely with their pro- materials and apparatus for thistein molecular weight. (See example rapidly growing technique.

'Nakos, G. and Mortenson, L., Biochemistry 10, 455 (1971).

- I Kd44'4te032nd & Griffin Ave., Richmond, CA 94804, Phone (415) 234-4130

Also in: Rockville Centre, N. Y.; St. Albans, England; Milano; MunichCircle No. 84 on Readers' Service Card

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KONTRONDIAPACKEquilibrium dialysis systemThe Diapack is a new equilibrium dialysis systemthat both simplifies and speeds up the handlingand accurate determination of binding parameters 4(association constants -K; thermodynamicsincluding free energy - AGO, enthalpy - AHO,entropy changes - AS0; binding sites - n) aswell as interactions between low molecular ligandsand biopolymers. Because the Diapack is easy touse and speeds up analysis, it gives you moreaccurate results. The system is optimized in allparameters to allow equilibrium dialysis studieswithin two to five hours in multiple numbers ofcells. Three cell options are available . . . macro,semi-micro and micro. All cell units are machinedfrom Teflon to eliminate absorption. Five equal-sized cells comprise one column. Up to fourcolumns or 20 cells may be mounted in thesystem's rotation unit. Membranes are of .025mmregenerated cellulose. Cells are simple toassemble, load or withdraw. Direct transfer ofsamples to appropriate analytical equipment foranalysis is easily accomplished.

KONTRONBox 702, Princeton, New Jersey 08540

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in Europe, contact Kontron-Technik A.G., CH-8031, Zurich, Switzerland.

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1162

Lenihan, Dept. of Clinical Physics andBioengineering, Western Regional HospitalBoard, 11 W. Graham St., Glasgow G49LF)

17-19. American Acad. of ClinicalToxicology, Chicago, Ill. (E. G. Com-stock, AACT, P.O. Box 2565, Houston,Tex. 77001)

17-22. Jaw Tumors/Baro Pathology,Intern. Soc. of Geographical Pathology,11th conf., Newcastle upon Tyne, Eng-land. (I. Rannie, Sutherland DentalSchool, Newcastle upon Tyne)

20-22. American Acad. of PhysicalMedicine and Rehabilitation, Denver,Colo. (C. C. Herold, AAPMR, 30 N.Michigan Ave., Chicago, Ill. 60602)

20-23. Food-Drugs from the Sea, 3rdconf., Kingston, R.I. (E. Miller, Hoffmann-La Roche, Inc., Nutley, N.J.)

20-25. American Assoc. of ClinicalChemists, Cincinnati, Ohio. (D. A. H.Roethal, AACC, 1155 16th St., NW,Washington, D.C. 20006)

20-25. Combustion, 14th intern. symp.,Combustion Inst., University Park, Pa.(CI, 986 Union Trust Bldg., Pittsburgh,Pa. 15219)

20-25. Federation of European Bio-chemical Socs., 8th annual, Amsterdam,Netherlands. (FEBS-BIOCHEM 72, RAIGebouw N.V., Europaplein 8, Amsterdam)

20-26. Low Temperature Physics, 13thintern. conf., Intern. Union of Pure andApplied Physics, Boulder, Colo. (D. G.McDonald, National Bureau of Standards,Boulder 80302)

21-23. Polymer Characterization, 2ndintern. symp., Battelle Memorial Inst.,Seattle, Wash. (F. A. Sliemers, Battelle,505 King Ave., Columbus, Ohio 43201)

21-24. International Assoc. of Milk,Food and Environmental Sanitarians, 59thannual, Milwaukee, Wis. (H. H. Thomas-son, IAMFE, Shelbyville, Ind. 46176)

21-25. Cloud Physics, intern. conf.,American Meteorological Soc., London,England. (AMS, 45 Beacon St., Boston,Mass.)

21-25. Extended Atmospheres and Cir-cumstellar Matter in Spectroscopic BinarySystems, Intern. Astronomical Union, Vic-toria, B.C., Canada. (K. 0. Wright,Dominion Astrophysical Observatory, R.R.7, Victoria)

21-25. Histochemistry and Cytochem.istry, 4th intern. congr., Kyoto, Japan. (K.Ogawa, Dept. of Anatomy, Kansai Medi-cal School, Moriguchi, Osaka, Japan)

21-25. International Conf. on Hydro-gen Bonding, Chemical Inst. of Canada,Ottawa, Ont. (M. K. Ward, Div. of Chem-istry, National Research Council of Can-ada, Ottawa KIA OR6)

21-25. Liquid Crystal, 4th intern. conf.,Kent, Ohio. (G. H. Brown, Liquid CrystalInst., Kent State Univ., Kent 44240)

21-25. International Congr. on Photo-biology, 6th, Bochum, Germany. (H. Tron-nier, Universitats-Hautklinik, D-7400Tubingen, Germany)

21-25. Science of Catalysis, 5th intern.congr., North American Catalysis Soc.,Miami Beach, Fla. (V. Haensel, UniversalOil Products Co., 30 Algonquin Rd., DesPlaines, Ill. 60016)

21-25. Underwater Physiology, 5thsymp., Undersea Medical Soc., Freeport,British Bahamas. (C. J. Lambertsen, Inst.

SCIENCE, VOL. 176

THREEfor the price of

TWOPurchase any two of the five symposium volumes listed above the line, and send yourpayment with your order and you may select any one of the titles listed below theline tree.

ARID LANDS IN TRANSITION

Scientists from 14 countries assess the changing conditions, the potential for develop-ment and possible solutions to problems of development of arid regions in 15 coun-tries around the world.Edited by Harold E. Dregne. 524 pages. 120 illustrations. 5 maps. Index. Retailprice: $15.75. AAAS member price: $13.50. ISBN 087168-090-4.

FOLK SONG STYLE AND CULTURE

Song style and dance style here become psycho-cultural indicators and, for the firsttime, the social and cultural import of the expressive act is firmly established. atruly staggering amount of data." Archives of General Psychiatry.Edited by Alan Lomax. 384 pages. 80 illustrations. 87 tables. Folk song text sources.Film sources. Bibliography. Index. Retail price: $16.75. AAAS member price: $14.50.ISBN 087168-088-2.

GROUND LEVEL CLIMATOLOGYTwenty papers dealing generally with the theme of weather and agriculture (includingforestry), and specifically with the climate closely surrounding plants and animals... the microclimate.Edited by Robert H. Shaw. 408 pages. 144 illustrations. Bibliography. Index. Retailprice: $12.50. AAAS member price: $10.50. ISBN 087168-086-6.

AGRICULTURE AND THE QUALITY OF OUR ENVIRONMENT

Basically concerned with the problem of how environmental quality affects agriculture,and how agriculture affects the quality of the environment. It identifies the part whichscience must play in solving environmental pollution problems.Edited by N. C. Brady. 476 pages. Bibliography. Author and subject indexes. Retailprice: $13.50. AAAS member price: $11.50. ISBN 087168-085-8.

GERM PLASM RESOURCESTwenty-five papers explore this subject according to origin of germ plasm, develop-mental programs, new approaches to uses and perpetuation, and protection of plantand animal germ plasm.Edited by Ralph E. Hodgson. 394 pages. 59 illustrations. Bibliography. Index. Retailprice: $9.75. AAAS member price: $8.50. ISBN 087168-066-1.

SCIENCE IN JAPANLeading Japanese scientists discuss the organization of research in their country andreview fundamental research in mathematics, biology, chemistry, physics, sociology,and psychology, as well as applied research in agriculture and other fields.Edited by Arthur H. Livermore. 496 pages. 165 illustrations. Bibliography. IndexISBN 087168-079-3.

SYSTEMS OF UNITS: NATIONAL AND INTERNATIONAL ASPECTS

Designed to focus attention on the growing problems of international usages of differentsystems.Edited by Carl F. Kayan. 308 pages. Index. Bibliography. ISBN 087168-057-2.

SYMPOSIUM ON BASIC RESEARCHLeading scientists and administrators examine many aspects of basic research. Itsimportance to society, the conditions that best foster it, and the need to developfavorable public opinion toward it.Edited by Dael Wolfle. 328 pages. ISBN 087168-056-4.

CIVIL DEFENSE

"The important consensus produced at this symposium is that the public should makethe decision on civil defense, and should be better informed in order to make a wisedecision."Edited by Henry Eyring. 144 pages. Paperbound. ISBN 087168-082-3.

Please send me the following items: Price:

Member E Non-member O

Name

Address

City State Zip

AMERICAN ASSOCIATION for theA ADVANCEMENT ot SCIENCE Mail to:

A A 1515 Massachusetts Avenue, N.W. Dept. AHWashington, D. C. 20005

PUReCULTURESNow a Reality!

With the NBS Ecologen, you can now growup to four pure and separate cultures in asingle mixed culture system. The Ecologenpermits interacting cells to grow in pureculture, while the metabolites of each pop-ulation diffuse freely through filters to influ-ence cell physiology, growth, and productyield. Because each individual culture re-mains homogeneous, cell growth variablesare easily observed. The Ecologen simu-lates the natural environment by producingmany of the variations found in nature. It isideal for use in studies of soils, water, oralcavities, digestive tracts, etc.

=Ik Ask for Booklet E 4OS/672

NEW BRUNSWICK SCIENTIFIC CO., INC.1130 SOMERSET ST.,NEW BRUNSWICK, N. J. 08903 201.846-4600

3 With NBS, Advanced Technology is a Way of LifeCircle No. 60 on Readers' Service Card

9 JUNE 1972 1163

NEW FROM DUCHLERAuto DENISI*FLOW®

lor density gradientsThe Auto Densi-Flow is ideal fordepositing generated gradientsor in the automatic withdrawal ofcentrifuged samples. It eliminatesthe need to push up the formedgradient with a heavy solutionwhich might cause diffusion ofbands and a spoiled experiment.This new automated instrumentalso deposits a generated grad-ient in a linear fashion into allcommercially available centri-fuge tubes.Additional advantages are: speedof operation; elimination of pierc-ing of centrifuge tubes andcompatibility with all types ofcentrifuge tubes without the needfor adapters. Write today forcomplete information on theAuto Densi-Flow-the moderntool for density gradient work.

Request Bulletin S2-5160ABUCHLER INSTRUMENTS DIV.NUCLEAR-CHICAGO CORP.A SUBSIDIARY OF GO.DlSEARLE I& co

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Circle No. 85 on Readers' Service Card

for Environmental Medicine, Univ. ofPennsylvania, Philadelphia, Pa. 19104)

21-26. Theoretical and Applied Me-chanics, 13th intern. congr., Moscow,U.S.S.R. (G. K Mikhailov, LeningradskiiProspekt 7, Moscow A-40)

21-30. International Geological Congr.,24th, Montreal, P.Q., Canada. (Secretary-General, 24th Intern. Geological Congr.,601 Booth St., Ottawa 4, Ont., Canada)

22-26. International Soc. on Throm-bosis and Haemostasis, 3rd congr., Wash-ington, D.C. (H. R. Roberts, Box 630,Chapel Hill, N.C. 27514)

22-30. International Congr. of Ento-mology, 14th, Canberra, Australia. (C. N.Smithers, Australian Museum, CollegeSt., Sydney 2000)

23-25. Aspects of Biological Gerontol-ogy, 2nd annual Rocky Mountain symp.on aging, Fort Collins, Colo. (Office ofConferences and Institutes, Room 178,Student Center, Colorado State Univ.,Fort Collins 80521)

23-25. Chemical Education Conf., Div.of Chemical Education, American Chem-ical Soc., South Hadley, Mass. (Miss A. J.Harrison, Dept. of Chemistry, Mt. Hol-yoke College, South Hadley 01075)

23-25. American Congr. of Rehabilita-tion Medicine, Denver, Colo. (C. C.Herold, ACRM, 30 N. Michigan Ave.,Chicago, Ill. 60602)25-27. Rural Sociological Soc., Baton

Rouge, La. (H. M. Sauer, Dept. of RuralSociology, South Dakota State Univ.,Brookings 57006)

27. Genetics Soc. of America, Minne-apolis, Minn. (M. W. Shaw, Room 523,Dept. of Biology, M. D. Anderson Hos-pital and Tumor Inst., Houston, Tex.77025)

27-30. American Inst. of Chemical En-gineers, 73rd natl., Minneapolis, Minn.(AICE, 345 E. 47 St., New York 10017)

27-1. American Inst. of Biological Sci-ences, Minneapolis, Minn. (J. R. Olive,AIBS, 3900 Wisconsin Ave., NW, Wash-ington, D.C. 20016)

27-1. American Chemical Soc., NewYork, N.Y. (F. T. Wall, ACS, 1155 16thSt., NW, Washington, D.C. 20036)

27-1. General and Molecular Genetics,Genetics Soc. of America, 41st annual,Minneapolis, Minn. (P. Snustad, Dept. ofGenetics, 301 Snyder Hall, Univ. ofMinnesota, St. Paul 55101)

27-1. American Soc. for HorticulturalScience, St. Paul, Minn. (C. Blackwell,ASHS, P.O. Box 109, 914 Main St., St.Joseph, Mich. 49085)

27-1. Society for Industrial Microbiol-ogy, St. Paul, Minn. (W. M. Stark, LillyResearch Labs., Eli Lilly & Co., Indian-apolis, Ind. 46206)

27-1. American Physiological Soc., Uni-versity Park, Pa. (R. G. Daggs, APS, 9650Rockville Pike, Bethesda, Md. 20014)

27-1. American Soc. of Plant Physiolo-gists, Minneapolis, Minn. (W. H. Klein,Smithsonian Radiation Biology Lab., 12441Parklawn Dr., Rockville, Md. 20852)

27-1. American Soc. of Plant Taxon-omists, Minneapolis, Minn. (D. M. Porter,Missouri Botanical Garden, 2315 TowerGrove Ave., St. Louis 63110)

27-1. Society of Protozoologists, Min-neapolis, Minn. (D. M. Hammond, Zool-ogy Dept., Utah State Univ., Logan 84321)

27-1. World Congr. of RehabilitationInternational, 12th intern., Sydney, Aus-tralia. (Rehabilitation International, 219E. 44 St., New York 10017)

27-1. Society for the Study of Evolu-tion, Minneapolis, Minn. (D. L. Jameson,Dept. of Biology, Univ. of Houston,Houston, Tex. 77004)

27-1. American Soc. of Zoologists,Minneapolis, Minn. (G. Sprugel, Jr., Illi-nois Natural History Survey, 179 NaturalResources Bldg., Urbana 61801)

27-2. International Soc. of Electro-chemistry, 23rd congr., Stockholm, Swe-den. (G. Wranglen, Royal Inst. of Tech-nology, 100 44 Stockholm 70)

27-2. Transfusion Congr., AnericanAssoc. of Blood Banks and Intern. Soc.of Blood Transfusions, Washington, D.C.(AABB, Suite 401, 915 19th St., NW,Washington, DC. 20006)

28. American Fern Soc., Minneapolis,Minn. (R. L. Hauke, Dept. of Botany,Univ. of Rhode Island, Kingston 02881)

28-29. Use of Tracers to Study Hetero-geneous Catalysis, intern. conf., New YorkAcad. of Sciences, New York, N.Y. (W.Likely, NYAS, 2 E. 63 St., New York10021)28-30. Mathematical Assoc. of Amer-

ica, Hanover, N.H. (H. Adler, Dept. ofMathematics, Univ. of California, Davis95616)

28-31. American Sociological Assoc.,New Orleans, La. (N. J. Demerath, ASA,1001 Connecticut Ave., NW, Washington,D.C. 20036)

28-1. Advances in Microbial Engineer-ing, 1st intern. symp., Marianske La'zne,Czechoslovakia. (Microbiological Inst.,Czechoslovak Acad. of Sciences, Bude-jovicka' 1083, Prague 4)

28-1. Biochemistry of Lipids, 15thintern. conf., The Hague, Netherlands.(B. H. Tritten, Unilever Research, P.O.Box 114, Vlaardingen, Netherlands)

28-1. Cybernetic Modeling of AdaptiveOrganizations, Science Committee, NorthAtlantic Treaty Organization, Porto, Por-tugal. (D. Howland, College of Admin-istrative Science, Ohio State Univ., 1775S. College Rd., Columbus 43210)

28-1. Electron Microscopy Soc. ofAmerica, Los Angeles, Calif. (G. C.Cocks, Olin Hall, Cornell Univ., Ithaca,N.Y. 14850)

28-2. Antibiotics: Biosynthesis andFunction, EUCHEM conf., Aarhus, Den-mark. (J. Hedegaard, Dept. of Microbiol-ogy, Polytechnical Univ., DK 2800Lyngby, Copenhagen, Denmark)

28-3. Phycological Soc. of America,Minneapolis, Minn. (Miss P. L. Walne,Dept. of Botany, Univ. of Tennessee,Knoxville 37916)

29-1. Discharges and Electrical Insula-tion in Vacuum, 5th intern. symp., Poz-nan, Poland. (A. S. Denholm, EnergySciences Inc., 111 Terrace Hall Ave.,Burlington, Mass. 01803)

30-2. Status of Physicians and Para-medical Staff, intern. conf., Bratislava,Czechoslovakia. (Czechoslovak MedicalSoc., Michiewiczova 18, Bratislava)

31-3. High-Resolution Infrared Spectro-scopy, 2nd intern., Prague, Czechoslovakia.(Inst. of Physical Chemistry, CzechoslovakAcad. of Sciences, Maichova 7, Prague)

SCIENCE, VOL. 176

--..0

RESEARCH DIRECTORSBIOLOGICAL STATIONS

Salaries to $29,700Fisheries Research Board of CanadaDepartment of the EnvironmentSt. Andrews, New BrunswickSt. John's, Newfoundland

Two senior research managers are required: one todirect the St. Andrews' Biological Station and theother to direct the St. John's Biological Station.Research at the St. Andrews' Station is aimedat improving the management and harvesting ofcommercial and recreational fisheries and on theaquatic environment with particular emphasis on qual-ity assessment and control.The research programs of the St. John's Station areconcerned with stocks that are presently or potentiallyimportant to fisheries in the Northwest Atlantic area,with special emphasis on the fisheries in the New-foundland area.Applicants should possess university graduation, pref-erably at the Doctorate level, and extensive researchexperience in a discipline related to the research pro-gram. In addition they should possess evidence ofability to provide leadership in managing a programof the scope indicated.Knowledge of the English language is essential.

Applications and further information can be obtainedby writing to:

BIO-PHYSICAL SCIENCES PROGRAM,PUBLIC SERVICE COMMISSION OF CANADA,OTTAWA, ONTARIO. KlA OM7

Please quote reference number 72-1151 in all correspondence.

9 JUNE 1972

PharmacologistOr

PhysiologicalPsychologist

An immediate opening exists at our Groton, Con-necticut Research Center for a pharmacologist toperform general CNS pharmacology with an op-portunity for limited conditioning research.

The successful candidate will possess a doctorallevel degree in pharmacology, physiological psy-chology or a closely related field and experiencein drug research. The applicant should be capableof dealing professionally with scientists fromdiverse disciplines.

Those interested should send their resume, inconfidence, to Mr. C. T. Kagel, Personnel Man-ager, Pfizer Central Research Division, EasternPoint Road, Groton, Conn. 06340.

An equal opportunity employer MIF

PRODUCT SAFETYThis is an opportunity for an ambitious, alert scientistwith managerial potential to make a solid contributionto Armour-Dial, Inc. in an area of growing importance.The ideal candidate will have a Ph.D., with experiencein toxicology, clinical testing or related areas. Ex-perience in a consumer product company, commercialtesting facility or a related organization actively work-ing in this field will prove useful.The right candidate will spearhead activities of a smallbut highly important group, with responsibility fordesigning and overseeing product safety and clinicaltesting programs at our Chicago based research lab-oratories. You will compile New Drug Applications andother government registrations for presentation tovarious agencies.You will be able to set standards, anticipate problemsand communicate the meaning of your tests to topmanagement and to government regulatory agencies.The compensation package is excellent. Opportunityfor further growtn in management responsibility isopen. Reply in confidence with resume and full salaryhistory to:

Wanita ZarumbaGreyhound TowersPhoenix, Arizona 85077

B ARMOUR-DIAL,INC.

An Equal Opportunity Employer (M/F)

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Write today for samples of Time Microscope Slide labelsand other Time Products for the laboratory. We will alsoprovide the name of your nearest dealer.NOTE: NEW ADDRESS. We have recently moved Into newfacilities; enlarged and automated to serve you better.

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Mliromiaologist Ph D. 2 years:'i exprieI Le ittcImt\ S a x0 in'l scC rlitd tClInical resati r' .a

ccciii miii otxxptt.ilvxce nixel lhmict' xx riting.lix & N iXI . r "' _I C)I| C! ittI' i: Ik t tI ?)t)t) }III ) 4 3-_'29

Pthlarnacologist, Ph.lD.. I'2 years' experieLlce inl-cludP3iv ari ;:a1rcscar t, clinical research. and17CL:ll;ItOs. :ornpli.anlce. an dbhiomedical writing.Br5Y, 1aL; ;C I F CE. X

IIE FACULIT 0F BIOLOG't NI'ERSIW OF HFIDELBERGCHAIR OF NLIUROBIOLOGY

ltit1 -im,rsity tlit, ISrLstitAlel tt IIC%N C11,11il o!\ciroiolicxx iItici Oohliit l 0Ih L.x,y anid i cpi ltionfl .ircirn x td ront

" Witii ppersonxsx tll quialificationxs miid rexeit^chiilli II.,inM11 t ,of nmderil Nlcrobioilox

A\pplic.itiOlls iClcllteiilO .lirric i, vxit.tic Idl iI-tno, 'icti0ns itOlci hib. t toto tniversitatHeidelherg, 69 lleidelberg 1, Grahengasse 1, \e5t(GermxInv. xc iorc l; Jin P12

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ICIIII)Cl .Aturc'>. Fori dcuttilk Or .ipplILat.liols \'writc' to}Prof. It. ILiudemann. 665 HobIlurg, 11.II. iol.luxtitul. '5 ext Germans.

BIOICIlIx'5MS11 pR ,wt(..doctixlid poxxitrolu t Rii. 1iii cii ii ticnihutic xxit' lvmiphtioxetx irxet-cr prc-

jxulx5c"tit)ici x.iIn ii qit lii xlix tuu() SCudL w-l lixlxxiJi xiii lid, txio rctirirtiecs toi Dr. T. H.Ji. D)ixision ot Biochenmistry. U nixersits Station.BlIs 3944. U nixsrsits of V555 oinulw. I aramie5% s omiing 820I70.

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I.

CHEMIST/PHARMACISTFEMALE/MALE

PharmaceuticalDevelopment

Position in our International Phormnceuticolp & D loboratory ct our Corporote ResearchCenter in Bloomfield for a Ph.D. Phormocistor Phormaceutical Chemist with experience inthe development of all types of phormaceu-ticol products, especially in solid forms &siiodern techniques of cooting tablets.for further information & consideration pleosedirect a resume of your quolificotions to

RESEARCH PERSONNEL

SCHERINGCORPORATION

60 ORANGE ST.BLOOMFIELD, N.J. 07003

Appiicants of all racesore encouraged to apply

ParetnnnI I |||!||||||||||||||||f||||||1jPOSMONS OPEN 0"11

P A HOLOGIS1. ExLp riencec itll It i icl tIIL'i i,0if (liac-tioxix .iiid research ii kidticx dicsf',ec ioli rac prietxe mcdical sc hool ili Is.txt ( list

1 P'isitittl ;itId x.tl.irx iLc',eii iic till..2, , if9NC I

AixoIspe iAJIic i Ixperimental Inimunologist-(Oncolo-gist \1 1) or Ph.1) ltii ;re- prixVtl li cii.Lcshootl ontt h Est (- oiisi. Sa.'i.r. ici1d , ii .

iB ON.tithie Bus 262 SCIF\( I-

PHARMl-ACOLOGIS I

-\iiti)itc,itixitxl .ite lniel cttit .) t tt>'i1 1

ApiItt lt1rofc sot I 13t cietnlicr pi rt Icxlit xxilth eto.iithcfiitionix ill the t,encral area ott 1:i,I

it tlt ioii.tel5 -tonxictsitogs iXii i.11th tcx tcudrinlilo-xxxtwocl hbe lelpfhil. I) ittCscx hctit

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italt tx Cliairman, Department of BiochemicalI'llharnmaclogy, School of Pharmacy, State I nliver-sits of Ness York at Butffalo. Buiffalo. Nes rYork14214.

f'OSTDOCTORAI, RESEARCH ASSOCIATE

, ol l itoch.r,11ciitl-rtri oatio it x lxccllcTit f.tcilities .ind stipend for to 2 years

kcpix to: Dr. William 0. SalivarBiology DepartmentMlarquette UniversityNilwaukee, Wisconsin 53233

D1P.PRTMENT OF PSYCHOLOGY).D)ALHOUSIE U N'i ERSI TI,HALIFAX, NOV:% SCOTIA

x* ISh t0 oinottOLICe ili,it xc 1licaV MI 0piiiii- tliti pitisition of Departmenital Chairmian [hi

p xitxixo .iitax sceiril att ractivefx Ittitrcw flii xniitttxxiiiitltcrestcd in hothi trictn, a rdescircht in:xxi iac iet ic x rtting: (i llerc ic 2t1 fiiil-tiinit

x cit}titoists iln e depaitnicnt. aIhii ts art.ictixc hsict process rescarch program (iii liiiI)1 l ltit ij ho(uLSed iti a flxxa in nilit litf.x,ciclces cottiplt\x xwhich ox rlookis lh;. AtlainrtiOcciti frorn the Halifax peninlsula .ind xwltilciicontain,s teaching anid rcscarchi facilities ott a patx tith tix in North Americi. (iii) The chairnitit(if tic (ieparttictit ilx is ttli iixSt1t11cc Of' .i fIttlirtinie idrnitnistrator, (ix) The salatat itel c onititonol tic position tire neoti.hcic We' .iri iwter-siexIt xoiiic0tic x Ito hiis deriltisi attcd iihl(itnt - iheificld of y.cncral expcrinicntal psxchoiog%, Iilier-eiteld parties shouIld applx to Chairman. SelectionCommittee, Department of Psi chologs, DallhousieIt niversitv, Halifax, Nosa Sco'tia.

Hliil UFELLOWSHIP 1POS 1 DOCTORAL FELLOW^ SHIP IN

RFSE.AiRCH ON SPERMATOGENFSIS1 xi- or threc-yxar appointtncntit for rcccro

l'it [) xii tereisitx in tinxNitcxiiittxn2 itoriiiion.lnlroitixxixil sxpcrlil.mtoc.cnesisx tillcic li rllti.

d0trinte xx niatogencsitx Begitiitt l ticxihiiSeit ci ciirric ltitil itae, inludcirdviteilnici of rc ci

icest o Pl'rofessor Irsing B. Fritz, Bantinig andBest Department of Ml1edical Research, LUniver-sits of Toronto. 112 Collegte Street. Toronito 101.Ontario. Canada.

The Market PlaceC,... . I."

.Ri,i-EE*S IExNCE. VC()t .Vi~