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SYSTEMS

COVERThe protective action of the wild-type p53 gene helpsto suppress tumors in humans. However, the p53 geneis the most commonly mutated gene in human cancer,and these mutations may actively promote tumorgrowth. The purple dots indicate some of the many

tumor types that may carry p53 mutations, includingbrain, esophagus, lung, breast, liver, prostate, andcolon. See Editorial, page 1953, Molecule of the Yeararticle, page 1958, and Perspective, page 1980. [Illus-tration: K. Sutliff and C. Faber Smith]

A Simple Kinetic Model of Polymer 2010Adsorption and Desorption

J. F. Douglas, H. E. Johnson, S. Granick

Molecular Light Emission Induced by 2012Inelastic Electron TunnelingE. Flaxer, 0. Sneh, 0. Cheshnovsky

Fabrication of Conducting Polymer r 2014InterconnectsC. L. Curtis, J. E. Ritchie, M. J. Sailor

Stable Isotope Enrichment in Paleowaters 2016of the Southeast Atlantic Coastal Plain,United StatesL. N. Plummer

Evidence of the Growth Plate and the O 2020Growth of Long Bones in Juvenile DinosaursC. Barreto, R. M. Albrecht, D. E. Bjorling,J. R. Homer, N. J. Wilsman

Mantle Plume Helium in Submarine 2023Basalts from the Galapagos PlatformD. W. Graham, D. M. Christie, K. S. Harpp,J. E. Lupton

Crystal Structure of the Repetitive 2027Segments of SpectrinY. Yan, E. Winograd, A. Viel, T. Cronin,S. C. Harrison, D. Branton

A Covalent Enzyme-Substrate 2030Intermediate with Saccharide Distortionin a Mutant T4 LysozymeR. Kuroki, L. H. Weaver, B. W. Matthews

Chromosome Condensation in Xenopus 2033Mitotic Extracts Without Histone HiK. Ohsumi, C. Katagiri, T. Kishimoto

Role of U6 snRNA in 5' Splice Site P 2035SelectionS. Kandels-Lewis and B. Seraphin

Connexin Mutations in X-Linked 2039Charcot-Marie-Tooth Disease

J. Bergoffen, S. S. Scherer, S. Wang, M. 0. Scott,L. J. Bone, D. L. Paul, K. Chen, M. W. Lensch,P. F. Chance, K. H. Fischbeck

Perceptual Organization and theJudgment of BrightnessE. H. Adelson

2042

T Cell Activation Antigen, CD26, as F. 2045a Cofactor for Entry of HIV in CD4+ CellsC. Callebaut, B. Krust, E. Jacotot, A. G.Hovanessian

Distinct Roles for Cyclin-DependentKinases in Cell Cycle ControlS. van den Heuvel and E. Harlow

2050

Receptive Field Reorganization in Dorsal 2054Column Nuclei During Temporary DenervationM. J. Pettit and H. D. Schwark

WT1-Mediated Growth Suppression 2057of Wilms Tumor Cells Expressing a WT1Splicing VariantD. A. Haber, S. Park, S. Maheswaran, C. Englert,G. G. Re, D. J. Hazen-Martin, D. A. Sens,A. J. Garvin

Peptide Translocation by Variants of the 2059Transporter Associated with AntigenProcessingM.-T. Heemels, T. N. M. Schumacher, K.Wonigeit, H. L. Ploegh

TECHNICAL COMMENTSMale Sexual Orientation and Genetic 2063EvidenceN. Risch, E. Squires-Wheeler, B. J. B. Keats;D. H. Hamer, S. Hu, V. Magnuson, N. Hu,A. M. L. Pattatucci

AAAS Board of Directors muininuinuinuinmininmuininininmuumin p Indicates accompanying feature ----- IEUEE'

F. Sherwood RowlandRetiring President,Chairman

Eloise E. ClarkPresident

Francisco J. AyalaPresident-elect

Robert A. FroschFlorence P. HaseltineWilliam A. Lester, Jr.

Alan SchriesheimJean'ne M. ShreeveChang-Lin TienWarren M. WashingtonNancy S. Wexler

William T. GoldenTreasurer

Richard S. NicholsonExecutive Officer

* SCIENCE (ISSN 0036-8075) is published weekly on Friday, exceptthe last week in December, by the American Association for the Ad-vancement of Science, 1333 H Street, NW, Washington, DC 20005. Sec-ond-class postage (publication No. 484460) paid at Washington, DC, and addi-tional mailing offices. Copyright 1993 by the American Association for theAdvancement of Science. The title SCIENCE is a registered trademark of theAAAS. Domestic individual membership and subscription (51 issues): $87 ($47allocated tosubscription). Domestic institutional subscription (51 issues): $205.Foreign postage extra: Mexico, Caribbean (surface mail) $50; other coun-tries (air assist delivery) $95. First class, airmail, student and emeritus rateson request. Canadian rateswith GSTavailable upon request, GST#125488122.Change of address: allow 6 weeks, giving old and new addresses and 11-digit

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SCIENCE * VOL. 262 * 24 DECEMBER 1993

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EDITORIAL

Molecule of the YearSome molecules are good guys, some are bad guys, and some become bad because they fail intheir functions. The molecule p53 is a good guy when it is functioning correctly. The specificcellular roles of p53 appear to be varied. It has a role in transcription (the first biochemicalstep in "reading" DNA), in cell cycle control (the steps leading to cell growth), and in manyother metabolic functions. It is a tumor suppressor in that it halts abnormal growth in normalcells and thus prevents cancer. However, a small change in p53, a mutation of one of its 393amino acids, can eliminate the surveillance capability of the protein and allow a cancer togrow. So a mutated p53 is frequently as bad as no p53 at all.

As in most practical outcomes derived from basic research, the implications of tumorsuppressors gradually permeated the consciousness of researchers in cell metabolism. Thus,the realization that p53 was one of those molecules was a seed that fell on fertile soil. Theexcitement generated by it and its fellow tumor suppressors is reaching a crescendo withexhilarating possibilities for prevention and cure of cancer. Therefore, we have chosen p53 asMolecule of the Year for 1993. (The nine runners-up for Molecule of the Year are describedon page 1959 in this issue; p53 is described further there and in a Perspective on page 1978.)

About 50 percent of all human cancers contain a mutation in p53, so hopes are highthat the molecule will provide new insights into treating the disease. Curing cancer andcuring a bacterial disease are very different problems. A bacterium has a different metabolismfrom that of a human cell, so scientists can target a metabolic pathway that kills the bacte-rium but has no human counterpart. Because cancer cells are simply human cells that growtoo well, a drug that kills cancer cells usually kills or weakens normal cells. We need to findthe pathway in cancer cells that's gone wrong and try to target it. The p53 protein is part of afundamental pathway in human cell growth, and finding p53's function allows scientists todevelop strategies for the diagnosis, prevention, and cure of cancers resulting from p53 defi-ciencies. For example, in the future, misshapen molecules caused by mutations in the genemay be brought back to the right shape by a drug that binds to the mutant p53 and pushes themutant back into the shape of the normal molecule. Another possible approach is geneticallyengineering the correct p53 molecule back into the cells in which a deficient p53 is unable toact in its tumor suppressor role. Identification of mutations in oncogenes may also haveprognostic value. Not all tumors contain a p53 mutation, but those that do are associatedwith a less favorable prognosis. Knowledge of a patient's p53 status could help determinewhich treatments would be most beneficial. The p53 protein is also identified with a processof programmed cell death that may be important in killing cancer cells, and further under-standing of this process provides hope for cancer therapy.

The great excitement in this field and the understanding that has already been ob-tained are typical of basic research. A rather innocuous molecule is shown to play a key rolein a basic body function. No possible clarification of its important role could have beenobtained without the background knowledge of biochemistry, cell biology, and genetics thatwas also the product of basic research. "Basic" research does not mean "no practical value"research, nor does it mean research with no goal in mind. The basic approach proceeds froman understanding that cancer results from uncontrolled growth, and therefore an understand-ing of what controls cell growth will ultimately lead to clues on ways to control cancer. Soonthe diagnostic opportunities that basic research has made available will enable clinicians todiagnose certain cancers at a stage early enough for effective intervention to take place.Therapeutic drugs are likely to follow. The finding of p53 and genetic markers for cancermeans that early detection can save lives now by known methods such as surgery and byproviding the opportunity for new drugs in the future.

Thus, p53 and its fellow tumor suppressors are generating an excitement that suggestsprevention now and hope for a cure of a terrible killer in the not-too-distant future. In thisendeavor the 1993 Molecule of the Year is certain to play a major role.

Daniel E. Koshland Jr.

SCIENCE * VOL. 262 * 24 DECEMBER 1993 1 953

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Published by the American Association for the Advance-ment of Science (AAAS), Science serves its readers as aforum for the presentation and discussion of important is-sues related to the advancement of science, including thepresentation of minority or conflicting points of view, ratherthan by publishing only material on which a consensus hasbeen reached. Accordingly, all articles published in Sci-ence-including editorials, news and comment, and bookreviews-are signed and reflect the individual views of theauthors and not official points of view adopted by the AAASor the institutions with which the authors are affiliated.

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1954

Elimination of Scholarships

Jay Hegde (Letters, 29 Oct., p. 637) assertsthat science students "enter graduate schoolfor the wrong reasons" when they seek"wholesale tuition waivers and stipends." Theimplication is that students, with their sightsset only on the big bucks they'll rake in asgraduate students, disregard that they may beunemployed after receiving their doctoratebecause of the lack of professional-level posi-tions. Anyone who has gone through gradu-ate school on a tuition waiver and stipendknows that big bucks it ain't, so that isunlikely to be the major reason someonechooses to continue his or her education.

There are a number of reasons why elimi-nation of scholarships is not in the bestinterest of scientists and the future of science.For one, eliminating scholarships would elim-inate students who come from low-incomefamilies. Second, scholarships provide an in-centive for all undergraduate students to com-pete and do their best. In addition to financialretum, scholarships bring prestige and affordstudents the opportunity to focus on academicendeavors either unencumbered or in con-junction with research-related jobs. Finally,departments that offer attractive scholarshipsare able to woo outstanding students whohave varied talents and interests. A pub-lished, summa cum laude biology student whoalso has a flair for chemistry may get an offerfrom the chemistry department that would behard to pass up.

Regardless of the number of students whocould not or chose not to pursue science dueto the elimination of scholarships, if the aimof science education is to secure the bestinterest of future scientists and the future ofscience, then the goal should be to gain thebroadest spectrum of talented science stu-dents. This is because, of course, a broad baseof input tends to stimulate innovation. Schol-arships are certainly one means to that end.

Sue Ann LewandowskiLumcon Library,

Louisiana Universities Marine Consortium,8124 Highway 56, Chauvin, LA 70344

The reduction or elimination of stipends andtuition waivers would have two immediateand counterproductive effects: it wouldgreatly bias the applicant pool toward thosefrom wealthy families, just at a time whenrecruitment efforts need to be broadened. Itwould also necessitate even larger under-graduate laboratory sections (absent suffi-cient teaching assistants), also just when the

SCIENCE * VOL. 262 * 24 DECEMBER 1993

quality of science education is being chal-lenged by classes that are too large.

I know of no evidence that the paltrysubsidies our graduate students receive arean incentive sufficient to encourage enter-ing graduate schools "for the wrong rea-son." Doctors and lawyers, unlike mostscientists, can usually manage to pay offloans accumulated during their studies. Idoubt a zoology graduate student wouldeven find a bank foolhardy enough to makea tuition loan.

Peter H. KlopferDepartment of Zoology,

Duke University,Durham, NC 27708-0325

m

Women in Biomedicine

With regard to the Random Samples item"Women in biomedicine: Still slugging it out"(29 Oct., p. 650), we are pleased to see theissue of women in science being directly ad-dressed, both by the Howard Hughes MedicalInstitute and in Science. However, we wouldlike to mention several additional points thatwe addressed in our discussion and place someof the quotes into context.

As women at various stages of our scien-tific careers, we think it is useful to talkabout the problems that women often face,the factors in our own lives that have helpedus overcome some of them, and potentialsolutions to those that we are still strugglingwith. We believe both positive and negativeexperiences should be included if such adialogue is to be of any value. Because thepositive aspects of our discussion were notreported in the Random Samples piece, ourcomments appeared to have a negative tonethat did not accurately reflect our feelings.We are particularly concerned about how

our comments about having children wereconveyed. Many women either drop out ofor do not pursue academic positions becauseof the difficulty in combining such a de-manding profession with the responsibilitiesof caring for young children. This conflict isnot a problem unique to science or to wom-en. Our purpose was to discuss ways toameliorate the problem, not to suggest thatwomen in science would "be well advised toforget about babies." We suggested (as havemany others) that the scientific establish-ment should recognize and respect the factthat people who have committed themselvesto caring for a dependent family member

LETTERSm

may experience a temporary loss in produc-tivity. Both universities and granting agen-cies need to find ways to offset this.

Another important area that was dis-cussed was that of mentors. All of us inde-pendently noted the role our mothers playedin supporting us in our career decisions andin setting an example for us to follow early inlife. We also talked about the crucial rolethat past and present mentors, both maleand female, have had in teaching us how tobe effective scientists, encouraging us tocontinue on and actively helping us to ad-vance. We cannot emphasize enough theimportance of these individuals in shapingour paths and the debt that we owe them.

Laura l. DavisHoward Hughes Medical Institute,

Department of Genetics,Duke University Medical Center,

Durham, NC 27710Ann Marie WhiteWhitehead Institute,

9 Cambridge Center, Cambridge, MA 02142

a

Bottleneck in Human Evolution andthe Toba Eruption

Ann Gibbons' Research News article "Pleis-tocene population explosions" (1 Oct., p. 27)discusses an apparent bottleneck in humanevolution in the period before about 50,000years ago and a possible link to climate cool-ing related to the massive Toba volcaniceruption in Sumatra 73,500 years ago. In arecent study of the possible effects of the Tobaeruption (1), we calculated that climate cool-ing for 1 or 2 years after the eruption couldhave been quite severe, representing "volcan-ic winter" conditions similar to those pro-posed in scenarios of nuclear winter followinga major nuclear exchange (2). Land temper-atures in the latitude zone from 300 to 700Nmay have ranged from about 50 to 150C colderthan normal, with widespread hard freezes inmid-latitudes and very low summer tempera-tures. Hemispheric temperature decreases of30 to 50C may have persisted for several years.Increased snow cover and sea ice and per-turbed sea-surface temperatures could haveled to longer term (decadal) cooling.

The Toba eruption occurred at a prom-inent transition from warm to cold climatesin the last glacial cycle, at a time of abruptice-sheet growth and sea-level fall andwhen Milankovitch insolation parameterswere such as to favor the growth of North-em Hemisphere ice sheets. Because climatecooling was already under way when Tobaerupted, it may be that sea-level fall relatedto the cooling had some role in triggeringthe eruption from an unstable magmachamber (1, 3). Calculations suggest thatthe brief cooling related to the dust and

aerosols from the Toba eruption may havebeen a contributing factor in the rapidclimatic switch.

Toba was apparently the largest explosiveeruption of the last few 100,000 years and itmay have been connected to a possibly uniqueLate Pleistocene bottleneck in human evolu-tion. More accurate dating of the eruption,and a record of its short-term effects on cli-mate could come from the detailed archive ofthe newly drilled GISP2 and GRIP ice coresin Greenland.

Michael R. RampinoDepartment of Earth System Science,

New York University,New York, NY 10003, and

NASA, Goddard Institute for Space Studies,2880 Broadway, New York, NY 10025

Stephen SelfDepartment of Geology and Geophysics,

School of Ocean and Earth Scienceand Technology,

University of Hawaii at Manoa,Honolulu, HI 96822

References

1. M. R. Rampino and S. Self, Nature 359, 50 (1992).2. R. P. Turco, 0. B. Toon, T. P. Ackerman, J. B.

Pollack, C. Sagan, Science 247, 166 (1990).3. M. R. Rampino and S. Self, Quat. Res. 40, 269

(1993).

The Baucus Bill

The ScienceScope item regarding proposedlegislation (the Baucus Bill) to protect fossilvertebrates on federal lands (15 Oct., p.

323) is a somewhat downbeat recitation ofthe situation. In fact, neither commercialnor amateur collectors can legally collectfossil vertebrates from federal lands at thepresent time. Thus, commercial collectorswho take fossils from federal lands are al-ready (would not be "put") "on the wrong

side of the law." The Baucus Bill recognizesthe valuable contributions made in the pastby amateur collectors and attempts, for thefirst time, to develop ways in which theamateurs can apply for a permit to collectfossils. As already in effect with permits toscientific or academic institutions, the per-

mits would specify that an arrangement hadbeen made to curate the scientifically sig-nificant specimens with a suitable institu-tion where they would be conserved (alongwith associated contextural data) for thecitizens of the United States.

Regardless of what museums or institu-tions may think is the case, none actually"has title" to the federal fossils under itsjurisdiction, and the Baucus Bill empha-sizes that any person collecting fossil verte-brates from federal land has responsibilityfor stewarding these fossils on behalf of the

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general public. Only by protecting fossilvertebrates from loss to our public domaincan we ensure that the vital informationlocked within them will be investigated bythe academicians who are trained to do so.

Michael 0. WoodburneSociety of Vertebrate Paleontology, and

Department of Earth Sciences,University of California,

Riverside, CA 92521-0423

a

Ice Man's Fungi:Discussion Rekindled

I write in response to the letters of HorstSeidler (18 Dec. 1992, p. 1868) andMichael Grant and Norris Denman (9Apr. 1993, pp. 146 and 147) concerningthe fungi found with the ice man. Onlyone of the two pieces of polypore has beenidentified so far as Piptoporus betulinus (1).This species contains the antibacterial"polyporenic acid C" (2), not, as Seidlersuggests, agaric acid. The latter is a typicalproduct of Laricifomes officinalis, anothernonagaric fungus "endowed with the mostastonishing medicinal virtues" (3) thatwas used in folk medicine, even by theancient Greeks and Romans (4).

Grant's creative statement that the Ty-rolean man was "well equipped for collect-ing insects or sharpening knives" deservesto be completed. The fruiting bodies of P.betulinus were also used for the manufac-ture of drawing charcoal (5), whereas anAustralian podiatrician reports havingpacked it behind ingrowing toenails with"excellent results" (8).

As to the question of whether or notthe ice man used the birch polypore "asfire-starting tinder," an additional thirdfungal material reveals more information:among the equipment found in his leatherbag (including several flint objects) was alarge amount of mysterious black stuff. Atfirst it was thought to be part of a prehis-toric repair kit (8), but this black stuff hasnow been clearly identified as "classicaltinder." It consists of loosely interwovencontext hyphae of the "true tinder brack-et" (Fomes fomentarius) still containingtraces of pyrite (9). The tissue does notshow the compactness of the native fungaltrama. It gives the impression of havingbeen treated mechanically in some way.Consequently, we have to assume that thetwo other pieces of polypore, each mount-ed separately on a leather strap, servedsome purpose other than making fire.

Reinhold P6derInstitut fur Mikrobiologie,

Leopold-Franzen~s- Universiit,dtA-6020 Innsbruck, Austria

SCIENCE * VOL. 262 * 24 DECEMBER 1993

References

1. R. P6der, U. Peintner, T. Pumpel, Bericht uber dasInternationale Symposium "Der Mann im Eis-EinFund aus der Steinzeit Tirols, " Innsbruck, Austria, 3to 5 June 1992, K. Spindler, Ed. (Veroffentlichungender Universitat Innsbruck, 1992), vol. 187, pp. 313-319.

2. J. H. Birkinshaw, E. N. Morgan, P. K. Findlay,Biochem. J. 50, 509 (1952).

3. A. H. R. Buller, Trans. Brit. Mycol. Soc. 5, 21 (1914).4. R. A. Blanchette, B. D. Compton, N. Y. Turner, R.

L. Gilbertson, Mycologia 84, 119 (1992).5. A. S. Bondartsev, The Potyporaceae of the Europe-

an USSR and Caucasia, E. Rabinovitz, Ed. (Keter,Jerusalem, 1971), p. 266.

6. R. N. Hilton, Mycologist 21, 121 (1987).7. A. Lippert and K. Spindler, Archeol. Osterr. 2, 11

(1991).8. F. Sauter and H. Stachelberger, Bericht uber das

Intermationale Symposium "Der Mann im Eis-inFund aus der Steinzeit Tirols, " Innsbruck, Austria, 3to 5 June 1992, K. Spindler, Ed. (vol. 187, Veroffentli-chungen der Universitat Innsbruck, 1992), pp. 442-453; R. Poder, T. Pumpel, U. Peintner, Der Mann imEis, K. Spindler, Ed., vol. 2, in press.

a

Manson Crater Extinctions

Richard Kerr (Research News, 29 Oct., p.659) exonerates the cometary impact thatproduced the Manson Crater in Iowa (andwas formerly suspected of having causedthe extinction of the dinosaurs) of "globalmayhem." However, it may well haveproduced mayhem on a subcontinentalscale. The Manson impact-generated tsu-nami deposit [Crow Creek Member, PierreShale (1)] separates strata containing as-semblages characteristic of different NorthAmerican marine vertebrate "ages" (Nio-braran and Navesinkan) with their dis-tinctive mosasaurs (2). Vertebrate remainsin continental strata, deposited along thewestern border of the Cretaceous interiorseaway shortly before and after the Man-son tsunami, also belong to separate NorthAmerican land mammal "ages" (Aquilanand Judithian) and reflect genus-levelchanges in crocodiles, dinosaurs, andmammals (3). It seems likely that localvertebrate faunas were badly disturbed bythe Manson impact and that taxa whichwere exterminated were replaced by immi-grants from beyond North America. Moreproblematic is the finding that post-Man-son survivors from the subcontinent bor-dering the eastern edge of the seaway showabundance patterns differing from those oftheir western contemporaries (4), perhapsbecause Asian/western immigrants wereblocked by the seaway.A study of the paleontological record

associated with the Manson crater will helpto reveal the lethal effects of bolide impactsof differing energies.

Dale A. RussellCanadian Museum of Nature,

Post Office Box 3443, Station "D,"Ottawa, Ontario KIP 6P4, Canada

References

1 G. A. Izett et al., Science 262, 729 (1993).2. D. A. Russell, Yale Univ., Peabody Mus. Nat. Hist.

Bull. 23, 210 (1967); Tyrrell. Mus. Palaeontol.Occas. Pap. 4 (1988).

3. J. R. Horner, Montana Geol. Soc. 1984 Field Conf(1984); J. A. Lillegraven and M. C. McKenna, Am.Mus. Novitates 2840 (1986); X. C. Wu and D. B.Brinkman, J. Vertebr. Paleontol. 13, 153 (1993).

4. B. S. Grandstaff and D. C. Parris, J. Vertebr.Paleontol. 13 (no. 3, Suppl.), 38 (1993).

a

Language and Math

Items such as 'Language may give Chinesean edge in math' (Random Samples, 29Oct., p. 651) lend respectability to lin-guistically and scientifically unsound spec-ulation. Chinese children, it is hypothe-sized are better at math because the wordsfor the numerals are shorter than they arein English. Language has nothing to dowith it. As a psycholinguist who special-izes in Chinese, I must point out thatRussian and Japanese children's mathscores knock the socks off those of U.S.children. Yet their numerals are muchlonger than in English ("one, two, three,four, five, six" in Russian are pronounced"adin, dva, tri, chyetiri, pyat, shest" and inJapanese, "iti, ni, san, si, go, roku"). In addi-

tion, Chinese has no grammar for singular orplural; one says the equivalent of "Mimihave three pen." If language affected arith-metic, Chinese children should do worse,not better.

Mary S. ErbaughCenter for Asian and Pacific Studies,

University of Oregon, Eugene, OR 97403

Corrections and Clarifications

Note 29 on page 1175 of the report "Lack of Nregions in antigen receptor variable region genesof TdT-deficient lymphocytes" by T. Komori etal. (27 Aug., p. 1 171) should have included theinformation that the murine TdT clone used inthat study was obtained from N. R. Landau, asdescribed in a 1987 paper by N. R. Landau, D.G. Schatz, M. Rosa, and D. Baltimore [Mol.Cell. Biol. 7, 3237 (1987)1 (reference 13 of thereport by Komori et al.).

Note 21 on page 1178 of the report "Micelacking TdT: Mature animals with an imma-ture lymphocyte repertoire" by S. Gilfillan etal. (27 Aug., p. 1175) should have includedthe information that the cDNA sequence ofmouse TdT was initially obtained by theauthors from the European Molecular BiologyLaboratory (accession number X04123), givenin a 1986 paper by 0. Koiwai, T. Yokota, T.Kageyama, T. Hirose, S. Yoshida, and K.Arai [Nucleic Acids Res. 14, 5777 (1986)].

Organic, Inorganic, Crystals, Zeolites,Biochemistry/ Student, Researcher,Lecturer, etc.

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otide used for mutagenesis was 5-GCA AGTTMAGG TAC AGC TAT GCA GCC TAC G-3'.

40. N. Bilgin, J. I. Lee, H.-y. Zhu, R. Dalbey, G. vonHeijne, EMBO J. 9, 2717 (1990).

41. M. T. Black, J. G. R. Munn, A. E. Allsop, Biomed.J. 282, 539 (1992).

42. J. L. San Millan, D. Boyd, R. Dalbey, W. Wickner,J. Beckwith, J. Bacteriol. 171, 5536 (1989).

43. G. S. Shelness, L. Lin, C. V. Nicchitta, J. Biol.Chem. 268, 5201 (1993).

44. E. A. Evans, R. Gilmore, G. Blobel, J. Cell Biol. 83,581 (1986).

45. R. K. Baker and M. 0. Lively, Biochemistry 26,8561 (1987).

46. J. T. YaDeau, C. Klein, G. Blobel, Proc. Nati.Acad. Sci. U.S.A. 88, 517 (1991).

47. E. A. Evans, G. S. Shelness, G. Blobel, J. Biol.Chem. 103, 291 (1986).

48. G. Greenburg, G. S. Shelness, G. Blobel, ibid.264, 15762 (1989).

49. G. Shelness and G. Blobel, ibid. 265,9512 (1990).50. G. Hortin and 1. Boime, Cell 24, 453 (1981).51. Media and general methods. YP and minimal

media were prepared as described (60). Cellswere grown in YP medium containing 2 percentgalactose (YP contained galactose in place ofglucose to avoid glucose repression of synthesis

of mitochondrial proteins), or 2 percent ethanoland 2 percent glycerol (YPEG) as carbon sourc-es. The SDS-PAGE analyses were performed on10 to 15 percent polyacrylamide gels. Immuno-logical detection of proteins after immunoblottingwas performed by enhanced chemiluminesence(Amersham).

52. B. C. Hann and P. Walter, Cell 67, 131 (1991).53. P. B. Wolfe, W. Wickner, J. M. Goodman, J. Biol.

Chem. 258,12073 (1983).54. P. Bohni, R. J. Deshaies, R. Schekman, J. Cell

Biol. 106, 1035 (1988).55. K. Kohrer and H. Domdey, Methods Enzymol.

194, 398 (1991).56. J. S. Cox, C. E. Shamu, P. Walter, Cell 73, 1197

(1993).57. G. M. Church and W. Gilbert, Proc. Nati. Acad.

SO., U.S.A. 81, 1991 (1984).58. A minor band present in mitochondria derived

from JN1 74(Aimp2) and JN1 74[plIMP2(S42A)-HA] cells that co-migrates with mature cy-tochrome cl is likely nonspecifically detected bythe antiserum cytochrome cl used in these stud-ies. We cannot rule out the possibility that theband represents a small amount of i-cytochromec, that has been proteolyzed by other proteases.It is unlikely, however, that this form accounts for

the PET+ phenotype of JN1\74[plIMP2(S42A)-HA]cells, because a similar amount is present inJN1 74(Aimp2) cells which are pet-.

59. R. S. Sikorski and P. Hieter, Genetics 122, 19(1989).

60. F. Sherman, J. B. Hicks, G. R. Fink, Methods inYeast Genetics (Cold Spring Harbor Laboratory,Cold Spring Harbor, NY, 1986).

61. T. Stearns, Stanford University.62. R. Rothstein, Columbia University.63. The following reagents were provided as follows:

antibodies to F1p-ATPase (M. P. Yaffe, Depart-ment of Biology, University of California, SanDiego), antibodies to cytochrome b2 and cy-tochrome cl (W. Neupert, University of Munich,Munich), antibodies to a-ketoglutarate dehydro-genase, to Impi p, and to cytochrome c (G.Schatz, Biocenter, Basel).

64. We thank R. Fletterick, T. Powers, C. Shamu, andK. Yamamoto for comments on the manuscript.Supported by a postdoctoral fellowship from theAmerican Heart Association (J.N.); an NIH grant(T.D.F.), and grants from the University of Califor-nia Academic Senate, the Alfred P. Sloan Foun-dation and NIH (P.W.).

20 August 1993; accepted 15 November 1993

AAAS-Newcomb Cleveland Prize

To Be Awarded for a Report, Research Article, or

an Article Published in Science

TheAAAS-Newcomb Cleveland Prize is awardedto the author of an outstanding paper published inScience. The value of the prize is $5000; the winneralso receives a bronze medal. The current competitionperiod began with the 4 June 1993 issue and endswith the issue of 27 May 1994.

Reports, Research Articles, and Articles that in-clude original research data, theories, or synthesesand are fundamental contributions to basic knowl-edge or technical achievements of far-reaching con-sequence are eligible for consideration for the prize.The paper must be a first-time publication of the au-thor's own work. Reference to pertinent earlier workby the author may be included to give perspective.

Throughout the competition period, readers are

invited to nominate papers appearing in the Re-ports, Research Articles, or Articles sections. Nomi-nations must be typed, and the following infor-mation provided: the title of the paper, issue inwhich it was published, author's name, and abrief statement of justification for nomination.Nominations should be submitted to the AAAS-Newcomb Cleveland Prize, AAAS, Room 924,1333 H Street, NW, Washington, DC 20005, andmust be received on or before 30 June 1994. Finalselection will rest with a panel of distinguishedscientists appointed by the editor of Science.

The award will be presented at the 1995 AAASannual meeting. In cases of multiple authorship, theprize will be divided equally between or among theauthors.

SCIENCE * VOL. 262 * 24 DECEMBER 1993

-1-1,

2004

The initial chapter, by George Redei, is afascinating account of past Arabidopsis re-search (including the author's difficulty inpublishing some of his original studies onArabidopsis mutants). The technical chap-ters on transformation using Agrobacterium,the establishment of linkage maps, genomemapping, analysis of proteins, and plant-pathogen interactions are interesting andclearly written, giving a context for theprotocols. The protocols themselves are pre-sented in such a useful way that postdoctoralstaff and graduate students rushed to take myreview copy of the book to use for oursoybean research. I believe the volume willbe valuable as well to those studying otherplant species. In it we have a book thatbelongs on the desk of every molecular plantscientist. -Peter M. Gresshoff, University ofTennessee

The Maize Handbook. MICHAEL FREELINGand VIRGINIA WALBOT, Eds. Springer-Verlag,New York, 1993. xxvi, 759 pp., illus., + plate.$79 or £55. Springer Laboratory.

"In modern times, the view that otherscientists are cooperators rather than com-petitors is unusual," write the editors ofthis volume, "but it is a key part of themaize community of scholars." Producedin this spirit, The Maize Handbook "repre-sents the collective efforts of the maizeresearch community to enumerate the keysteps of standard procedures and to dissem-

2072

inate these protocols for the commongood," including that of those workingwith other higher plants to which theprocedures may be applicable. In all, 129authors have contributed 133 items to theenterprise. The volume opens with ninebrief contributions setting forth the basicsof maize development and morphology.Another ten papers under the headingCell Biology deal mainly with techniquesrelated to microscopy, rather than withcellular processes per se. The remaining640 pages of the text are given over to theprotocols, among which are interspersedsome not strictly methodological discus-sions of various features of maize such asthe anthocyanin gene system. Of theitems in this part of the book 63 arecategorized as genetics, 37 as molecularbiology, and 14 as cell culture. In lengththey range from one page (for instance,Birchler on ring chromosomes) to 17(Chang and Neuffer on chromosome be-havior during microsporogenesis). Illustra-tions include a 10'/2-page table of recipro-cal translocations between A chromo-somes (Coe) and a color plate showingresults of gene tagging involving Ac andDs transposable elements (Dellaporta andMoreno). Reference lists are appended tothe individual contributions, and a 34-page subject index is included at the endof the book. In the preface the editorsprovide as other aids to the reader infor-mation about the Maize Genetics Cooper-ation Newsletter and a list of other booksthat should be in a "robust" library of thesubject.

-Katherine Livingston

SCIENCE * VOL. 262 * 24 DECEMBER 1993

Books ReceivedThe Analysis of Natural Waters. T. R. Crompton.

Oxford University Press, New York, 1933. 2 vols. Vol.1, Complex-Formation Preconcentration Techniques.xii, 216 pp., illus. $52.50. Vol. 2, Direct Preconcentra-tion Techniques. xii, 249 pp., illus. $60.

And Yet It Moves. Strange Systems and SubtleQuestions in Physics. Mark P. Silverman. CambridgeUniversity Press, New York, 1993. xviii, 266 pp., illus.$49.95; paper, $24.95.

Applications of Environment-Behavior Re-search. Case Studies and Analysis. Paul D. Cherulnik.Cambridge University Press, New York, 1993. xiv, 342pp., illus. $64.95; paper, $24.95. Cambridge Series inEnvironment and Behavior.

Biology. Exploring Life. Gil Brum, Larry McKane,and Gerry Karp. 2nd ed. Wiley, New York, 1994.Variously paged, illus. $58.95.

Biology of Salmonella. Felipe Cabello et at., Eds.Plenum, New York, 1993. xii, 470 pp., illus. $115.NATO Advanced Science Institutes Series A, vol. 245.From an institute, Portorosa, Italy, May 1992.

The Biophilia Hypothesis. Stephen R. Kellert andEdward 0. Wilson, Eds. Island Press, Washington,DC, 1993. viii, 484 pp., illus. $27.50.

California's Changing Landscapes. Diversityand Conservation of California Vegetation. MichaelBarbour et al. California Native Plant Society, Sacra-mento, CA, 1993. x, 246 pp., illus. Paper, $24.95.

Capillary Electrophoresis of Small Moleculesand lons. Petr Jandik and Gunther Bonn. VCH, NewYork, 1993. x, 298 pp., illus. $65.

Catalytic Asymmetric Synthesis. lwao Ojima,Ed. VCH, New York, 1993. xiv, 476 pp., illus. $110.

Data Analysis for the Chemical Sciences. AGuide to Statistical Techniques. Richard C. Graham.VCH, New York, 1993. xx, 536 pp., illus. $65.

Digital Woes. Why We Should Not Depend on Soft-ware. Lauren Ruth Wiener. Addison-Wesley, Reading,MA, 1993. xx, 245 pp., illus. $22.95.

Dissociative Recombination. Theory, Experi-ment, and Applications. Bertrand R. Rowe, J. Brian A.Mitchell, and Andr6 Canosa, Eds. Plenum, New York,1993. x, 282 pp., illus. $95. NATO Advanced ScienceInstitutes Series B, vol. 313. From a workshop, SaintJacut de la Mer, Brittany, France, May 1992.

The Ecology of Commerce. A Declaration ofSustainability. Paul Hawken. HarperBusiness, NewYork, 1993. xviii, 250 pp. $23.

80 Years of Hashimoto Disease. Shigenobu Na-gataki, Toru Mori, and Kanji Torizuka, Eds. ExcerptaMedica (Elsevier Science), Amsterdam, 1993. xxvi,721 pp., illus. $237.25 or Dfl. 415. From a symposium,Fukuoka, Japan, Dec. 1992.

The Encyclopedia of Mental Health. Ada P. Kahnand Jan Fawcett. Facts on File, New York, 1993. xii,464 pp. $45.

The Engineer in the Garden. Genes and Genet-ics. From the Idea of Heredity to the Creation of Life.Colin Tudge. Cape, London, 1993. xii, 398 pp. £17.99.

Epidermal Growth Factors and Cytokines. Tho-mas A. Luger and Thomas Schwarz, Eds. Dekker,New York, 1993. xviii, 486 pp., illus. $165. ClinicalDermatology, 10.

Field Guide to Coastal Wetland Plants of theSoutheastern United States. Ralph W. Tiner. AbigailRorer, illustrator. University of Massachusetts Press,Amherst, 1993. xiv, 328 pp. + plates. $50; paper,$17.95.

Flora of North America. North of Mexico. NancyR. Morin, Convening Ed. Oxford University Press, NewYork, 1993. Vol. 1, Introduction. xxii, 372 pp., illus. Vol.2, Pteridophytes and Gymnosperms. xvi, 475 pp.,illus. Each. vol., $75.

G. I. Budker. Reflections and Remembrances.Boris N. Breizman and James W. Van Dam, Eds.American Institute of Physics, New York, 1993. xviii,364 pp. + plates. $45. Translated from the Russianedition (1988).

Games of Life. Explorations in Ecology, Evolution,and Behaviour. Karl Sigmund. Oxford UniversityPress, New York, 1993. viii, 244 pp., illus. $49.95;paper, $17.95.

Gene Conservation and Exploitation. J. Perry

Vignettes: Around the CampusesThe University of Arizona is a real Ken and Barbie kind of place, with frats andsororities and lots of beautiful people.

-Chris Langton, as quoted by M. Mitchell Waldrop in Complexity:The Emerging Science at the Edge of Order and Chaos (Simon and Schuster)

A visitor ... accustomed to the look and traffic patterns of major universities mightfind the grounds of the MIT campus remarkably underpopulated. Responsiblepeople can speedskate over the sidewalks and do.

-Fred Hapgood, in Up the Infinite Corridor:MIT and the Technical Imagination (Addison-Wesley)

I don't like it here in Palo Alto.... I am in the academic demimonde. am an editorand manager for a marginal publisher of doctoral dissertations languishing be-cause they're too specialized or because they fall outside the desiderata of theregular university presses.

-The sometime-anthropologist main character inNorman Rush's novel Mating (Knopf, 1991; Vintage paperback)

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Gustafson, R. Appels, and P. Raven, Eds. Plenum,New York, 1993. x, 224 pp., illus. $69.50. StadlerGenetics Symposia Series. From a symposium, Co-lumbia, MO, Sept. 1991.

Genome Maps and Neurological Disorders. KayE. Davies and Shirley M. Tilghman, Eds. Cold SpringHarbor Laboratory Press, Cold Spring Harbor, NY,1993. viii, 125 pp., illus. $49. Genome Analysis, vol. 6.

HPLC Detection. Newer Methods. Gabor Patonay,Ed. VCH, New York, 1993. xii, 236 pp., illus. $95.

Human Feelings. Explorations in Affect Develop-ment and Meaning. Steven L. Ablon et al., Eds.Analytic Press, Hillsdale, NJ, 1993. xxii, 431 pp., illus.$45.

Humans as Components of Ecosystems. TheEcology of Subtle Human Effects and Populated Ar-eas. Mark J. McDonnell and Steward T. A. Pickett,Eds. Springer-Verlag, New York, 1993. xxii, 364 pp.,illus. $49. From a conference, 1991.

Integrated Public Lands Management. Principlesand Applications to National Forests, Parks, WildlifeRefuges, and BLM Lands. John B. Loomis. ColumbiaUniversity Press, New York, 1993. xxiv, 474 pp., illus.$50.

Intelligent Behavior in Animals and Robots.David McFarland and Thomas Bosser. MIT Press,Cambridge, MA, 1993. xiv, 308 pp., illus. $39.95.Complex Adaptive Systems.

Introduction to Computer Performance Analy-sis with Mathematica. Arnold 0. Allen. AP Profes-sional (Academic), Cambridge, MA, 1993. xx, 356 pp.,illus., + diskette. $49.95.

Introduction to Mathematical Philosophy. Ber-trand Russell. Dover, New York, 1993. viii, 208 pp.,illus. Paper, $6.95. Reprint, 1920 ed.

Keeping All the Pieces. Perspectives on NaturalHistory and the Environment. Whit Gibbons. Smithson-ian Institution Press, Washington, DC, 1993. xxii, 182pp. Paper, $16.95 or £10.95.

Kepler. Max Caspar. Dover, New York, 1993. 441pp. Paper, $10.95. Translated from the German edi-tion (1948) by C. Doris Hellman. Augmented reprint,1959 ed.

Kinetic Theory of Living Pattern. Lionel G. Har-rison. Cambridge University Press, New York, 1993.xx, 354 pp., illus. $69.95. Developmental and CellBiology Series, 28.

The Language of Colloid and Interface Science.A Dictionary of Terms. Laurier L. Schramm. AmericanChemical Society, Washington, DC, 1993. xii, 195 pp.$69.95; paper, $39.95. ACS Professional ReferenceBook.

Lasers and Optical Fibers in Medicine. AbrahamKatzir. Academic, San Diego, CA, 1993. xx, 317 pp.,illus. $85. Physical Techniques in Biology and Medicine.

Life History Invariants. Some Explorations ofSymmetry in Evolutionary Ecology. Eric L. Charnov.Oxford University Press, New York, 1993. xvi, 167 pp.,illus. $37.50; paper, $19.95. Oxford Series in Ecologyand Evolution.

Ufe into Art. Isadora Duncan and Her World.Dor6e Duncan, Carol Prati, and Cynthia Splatt, Eds.Norton, New York, 1993. 199 pp., illus. $40.

The Literature of Animal Science and Health.Wallace C. Olsen, Ed. Cornell University Press, Ithaca,NY, 1993. viii, 404 pp., illus. $79.95. Literature of theAgricultural Sciences.

Magnetism and Basalts. C. Radhakrishnamurty.Geological Society of India, Bangalore, 1993. xvi, 208pp., illus. Paper, $30 or Rs 250. Memoir 26.

The Maple Handbook. Darren Redfern. Springer-Verlag, New York, 1993. vi, 497 pp., illus. Spiral bound,$29.

Mastering C Pointers. Tools for ProgrammingPower. Robert J. Traister. 2nd ed. AP Professional(Academic), Cambridge, MA, 1993. xii, 163 pp. +diskette. Paper, $35.95.

Mathematical Theory of Oil and Gas Recovery.With Applications to Ex-USSR Oil and Gas Fields. PavelBedrikovetsky. Gren Rowan, Ed. Kluwer, Norwell, MA,1993. xx, 575 pp., illus. $199 or £129 or Dfl. 325.Petroleum Engineering and Development Studies, vol. 4.Translated from the Russian by Ruth Loshak.

Mathematics for Ooerations Research. W. H.Marlow. Dover, New York, 1993. xviii, 483 pp., illus.Paper, $12.95. Dover Books on Advanced Mathemat-ics. Revised reprint, 1978 ed.

Maya Cosmos. Three Thousand Years on theShaman's Path. David Freidel, Linda Schele, and JoyParker. Justin Kerr and MacDuff Everton, photogra-phers. Morrow, New York, 1993. 543 pp., illus., +plates. $30.

Medicaid Financing Crisis. Balancing Responsi-bilities, Priorities, and Dollars. Diane Rowland, JudithFeder, and Alina Salganicoff, Eds. American Associa-tion for the Advancement of Science, Washington, DC,1993. xvi, 222 pp., illus. Paper, $22.95; to AAASmembers, $18.35. AAAS Publication, no. 93-04S.

Memory Search by a Memorist. Charles P.Thompson, Thaddeus M. Cowan, and Jerome Frie-man. Erlbaum, Hillsdale, NJ, 1993. xiv, 156 pp., illus.$39.95.

The Neurobiology of Neural Networks. DanielGardner, Ed. MIT Press, Cambridge, MA, 1993. xiv,227 pp., illus. $45. Computational Neuroscience.

The Neuropsychology of Attention. Ronald A.Cohen with Yvonne A. Sparling-Cohen and Brian F.O'Donnell. Plenum, New York, 1993. xx, 545 pp., illus.$75. Critical Issues in Neuropsychology.

New Concepts in the Pathogenesis of NIDDM.Claes Goran Ostenson, Suad Efendi6, and MladenVranic, Eds. Plenum, New York, 1993. x, 316 pp., illus.$79.50. Advances in Experimental Medicine and Biolo-gy, vol. 334. From a symposium, Stockholm, Sept. 1992.

New Frontiers in Cancer Causation. Olav HilmarIversen, Ed. Taylor and Francis, Philadelphia, 1993.xxiv, 444 pp., illus. $75. From a conference, Oslo, Aug.1992.

Ocean. Photographs from the World's GreatestUnderwater Photographers. Boyce Thorne-Miller. Col-lins, San Francisco, 1993. 240 pp., illus. $45.

Operation Epsilon. The Farm Hall Transcripts.Institute of Physics, Bristol, U.K., and University ofCalifornia Press, Berkeley, 1993. x, 313 pp., illus. $30.

Optics in Astronomy. J. V. Wall, Ed. CambridgeUniversity Press, New York, 1993. xii, 288 pp., illus.$59.95. From a conference, Cambridge, U.K., Sept.1991.

Organic Geochemistry. Principles and Applica-tions. Michael H. Engel and Stephen A. Macko, Eds.Plenum, New York, 1993. xxiv, 861 pp., illus. $79.50.Topics in Geobiology, vol. 11.

The Origins of Modern Humans. Roger Lewin.Scientific American Library (HPHLP), New York, 1993(distributor, Freeman, New York). xii, 204 pp., illus.$32.95.

Our Earliest Ancestors. Bjorn Kurt6n. Viking Nys-trom, illustrator. Columbia University Press, New York,1993. xii, 158 pp. $19.95. Translated from the Swedishby Erik J. Friis.

A Practical Guide to Human Cancer Genetics. S.V. Hodgson and E. R. Maher. Cambridge UniversityPress, New York, 1993. xviii, 240 pp., illus. $79.95;paper, $34.95.

The Preocular Tear Film. Janos Feh6r. Akad6miaiKiad6, Budapest, 1993. 142 pp., illus. Paper, $30.Pathophysiology of the Eye, vol. 1.

Quantitative Assessment in Epilepsy Care. Har-ry Meinardi et al., Eds. Plenum, New York, 1993. viii,214 pp., illus. $69.50. NATO Advanced Science Insti-tutes Series A, vol. 255. From a workshop, Porto,Portugal, April, 1992.

Quantitative Particle Physics. Maurice L6vy et al.,Eds. Plenum, New York, 1993. x, 434 pp., illus. $120.NATO Advanced Science Institutes Series B, vol. 311.From an institute, Carg6se, France, July 1992.

Random Walks in Biology. Howard C. Berg. 2nded. Princeton University Press, Princeton, NJ, 1993.xii, 152 pp., illus. Paper, $12.95.

Receptors. Models for Binding, Trafficking, andSignaling. Douglas A. Lauffenburger and Jenifer J.Linderman. Oxford University Press, New York, 1993.x, 365 pp., illus. $69.95.

Reporting Experimental Data. Selected Reprints.Howard J. White, Jr., Ed. American Chemical Society,Washington, DC, 1993. x, 365 pp., illus. $89.95.

Representations and Characters of Groups.Gordon James and Martin Liebeck. Cambridge Uni-versity Press, New York, 1993. x, 419 pp., illus. $69.95;paper, $29.95.

Resources of Near-Earth Space. John S. Lewis,Mildred S. Matthews, and Mary L. Guerrieri, Eds.University of Arizona Press, Tucson, 1993. x, 977 pp.,

SCIENCE * VOL. 262 * 24 DECEMBER 1993

illus. $75. Space Science Series.Saltmarsh Ecology. Paul Adam. Cambridge Uni-

versity Press, New York, 1993. xii, 461 pp., illus.Paper, $37.95. Cambridge Studies in Ecology.

Scanning Tunneling Microscopy and Spectros-copy. Theory, Techniques, and Applications. Dawn A.Bonnell, Ed. VCH, New York, 1993. xiv, 436 pp., illus.$125.

Semiconductor Interfaces, Microstructures andDevices. Properties and Applications. Zhe ChuanFeng, Ed. Institute of Physics, Philadelphia, 1993. xiv,293 pp., illus. $134 or £67.50. Based on a meeting,March 1991.

Structure Determination by X-Ray Crystallogra-phy. M. F. C. Ladd and R. A. Palmer. 3rd ed. Plenum,New York, 1993. xxvi, 586 pp., illus. $59.50.

Subcellular Biochemistry. Vol. 21, EndoplasmicReticulum. N. Borgese and J. R. Harris, Eds. Plenum,New York, 1993. xxiv, 358 pp., illus. $89.50.

Superconductivity. The Next Revolution? Gian-franco Vidali. Cambridge University Press, New York,1993. xii, 165 pp., illus. $49.95; paper, $17.95.

Thermodynamics of Chaotic Systems. An Intro-duction. Christian Beck and Friedrich Schlogl. Cam-bridge University Press, New York, 1993. xx, 286 pp.,illus. $64.95. Cambridge Nonlinear Science Series, 4.

Thermodynamics of Irreversible Processes.Bernard H. Lavenda. Dover, New York, 1993. xvi, 182pp. Paper, $7.95. Reprint, 1978 ed.

Thinking About Biology. An Invitation to CurrentTheoretical Biology. Wilfred D. Stein and Francisco J.Varela, Eds. Addison-Wesley, Reading, MA, 1993. xiv,330 pp., illus., + plates. $41.95; paper, $26.95. SantaFe Institute Studies in the Sciences of Complexity.Lecture Notes, vol. 3.

Tiger-Wallahs. Encounters with the Men WhoTried to Save the Greatest of the Great Cats. GeoffreyC. Ward with Diane Raines Ward. HarperCollins, NewYork, 1993. xii, 175 pp., illus. $35.

Toxic Risks. Science, Regulation, and Perception.Ronald E. Gots. Lewis, Boca Raton, FL, 1993. x, 277pp., illus. $49.95.

Translational Regulation of Gene Expression 2.Joseph llan, Ed. Plenum, New York, 1993. xxiv, 493pp., illus. $95.

Transport and Thermal Properties of f-ElectronSystems. G. Oomi, H. Fujii, and T. Fujita, Eds. Plenum,New York, 1993. x, 311 pp., illus. $89.50. From aworkshop, Hiroshima, Japan, Aug. 1992.

Understanding Aphasia. Harold Goodglass. Ac-ademic, San Diego, CA, 1993. xii, 297 pp., illus.$54.95. Foundations of Neuropsychology.

The Unnatural Nature of Science. Lewis Wolpert.Faber and Faber, London, 1993. xiv, 191 pp. Paper,£6.99. Reprint, 1992 ed.

The Virtual Community. Homesteading on theElectronic Frontier. Howard Rheingold. Addison-Wes-ley, Reading, MA, 1993. x, 325 pp. $22.95.

Visual BASIC for DOS. Building Scientific andTechnical Applications. James W. Cooper. Wiley, NewYork, 1993. xxii, 401 pp., illus. Paper, $34.95.

We Have Never Been Modern. Bruno Latour.Harvard University Press, Cambridge, MA, 1993. x,157 pp., illus. $29.95; paper, $12.95. Translated fromthe French edition (1991) by Catherine Porter.

Weed Seeds of the Great Plains. A Handbook forIdentification. Linda W. Davis. Published for the Coop-erative Extension Service, Kansas State University byUniversity Press of Kansas, Lawrence, 1993. vi, 145pp., illus., + plates. $25. Agricultural Experiment Sta-tion contribution no. 92-125-B.

Who Speaks for Tokyo Bay? Blair T. Bower andKatsuki Takao, Eds. Balkema, Brookfield, VT, 1993.xiv, 141 pp., illus. $55 or Dfl. 95. Coastal WatersSeries, 3.

Why Zebras Don't Get Ulcers. A Guide to Stress,Stress-Related Diseases, and Coping. Robert M. Sa-polsky. Freeman, New York, 1993. xiv, 368 pp., illus.$21.95.

World of Fairs. The Century-of-Progress Exposi-tions. Robert W. Rydell. University of Chicago Press,Chicago, 1993. x, 269 pp., illus. $49.95; paper,$1 6.95.

The World of the Celts. Simon James. Thamesand Hudson, New York, 1993 (distributor, Norton, NewYork). 192 pp., illus. $29.95.

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