PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA

Officers BRUCE ALBERTS, President of the JACK HALPERN, Vice President Academy PETER H. RAVEN, Home Secretary F. SHERWOOD ROWLAND, Foreign Secretary MILDRED S. DRESSELHAUS, Treasurer

Editor-in-Chief NICHOLAS R. COZZARELLI

Editorial Board PETER J. BICKEL JACK HALPERN PAUL R. SCHIMMEL of the MICHAEL T. CLEGG ERIC R. KANDEL STUART L. SCHREIBER Proceedings MARSHALL H. COHEN RICHARD A. LERNER CARLA J. SHATZ STANLEY N. COHEN HARVEY F. LODISH CHRISTOPHER A. SIMS MAX D. COOPER PHIL W. MAJERUS ALLAN C. SPRADLING JAMES E. DARNELL, JR. ARNO G. MOTULSKY LARRY R. SQUIRE IGOR B. DAWID RONALD L. PHILLIPS CHARLES F. STEVENS HERMAN N. EISEN TOM POLLARD JOANNE STUBBE RAYMOND L. ERIKSON STANLEY B. PRUSINER KARL K. TUREKIAN RONALD M. EVANS CHARLES RADDING IRVING L. WEISSMAN NINA FEDOROFF GIAN-CARLO ROTA SHERMAN M. WEISSMAN CHARLES FEFFERMAN DAVID D. SABATINI PETER G. WOLYNES JOSEPH L. GOLDSTEIN GOTTFRIED SCHATZ

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'997 J4wards

0 . i/ftor Ol/1/iFl4atloNse

( / he National Academy of Sciences presents a number of awards-spanning a range of scientific disciplines-to recognize contributions to science. The awards to be presented in 1997 are described on the following pages; nominations, which should be submitted on a copy of the form on page vii, will be accepted through September 1, 1996. For further information, contact the Academy at (202) 334-2444 (Internet: [email protected]; WWW: http://www.nas.edu/nas).

* John 1. Carty Award * NAS Award for Behavioral Research for the Advancement of Science Relevant to the Prevention of Nuclear War (anthropology) * NAS Public Welfare Medal * NAS Award for Chemistry in * NAS Award for Scientific Reviewing Service to Society (evolutionary biology) * Henry Draper Medal * G. M. Smith Medal (astronomical physics) (phycology) * Gibbs Brothers Medal * 1. Lawrence Smith Medal (naval architecture) (meteoric bodies) * NAS Award for Initiatives in Research * Troland Research Awards (psychology) (condensed matter physics) * Selman A. Waksman Award * Richard Lounsbery Award in Microbiology (biology and medicine) * Charles Doolittle Walcott Medal (pre- * NAS Award in Molecular Biology Cambrian and Cambrian life and history)

iii John J. Carty Award for the Gibbs Brothers Medal Advancement of Science Medal and prize of $5,000 awarded every two years for -Established by the AT&T Company 0outstanding contributions in the field of naval archi- i0 f0 ~tecture and marine engineering. Established bygift of Medal and prize of $25,000 awarded&every three years tecturand m ine engineering. Estbsh for noteworthy and distinguished accomplishments in W any field of science within the charter of the Academy; Recipients: the 1997 field is anthropology. 1965 Frederick Henry Todd 1967 Alfred Adolf Heinrich Kiel 1970 Henry A. Schade NAS Award for Chemistry 1974 Phillip Eisenberg in Service to Society 1976 John Charles Niedermair 1979 Matthew G. Forrest -Established E. I.dui Pont de Nemburs & by -EstablisdCbmpanyby E. .1988 Leslie A. Harlander Prize of $20,000 awarded every two years for contribu- 1991 Bruce G. Collipp tions to chemistry, either in fundamental science or its 1993 Olin J. Stephens 11 application, that clearly satisfy a: societal need. The 1995 Owen H. Oakley 1995 award was given to an industrial chemist. The 1997 award will be given to a chemist from an academic, government, or nonprofit organization. NAS Award for Initiatives in Research by AT&T Bell Laboratories in honor of Recipients: William-Established0. Baker 1991 viauimirInnHaensei I,ll , 1993 Harold S. Johnston Prize of $15,000 awarded annually to recognize innova- 1995 P. Roy Vagelos tive young scientists and to encourage research likely to lead toward new capabilities for human benefit. The award is to be given to a citizen of the United States, Henry Draper Medal preferably no older than 35 years of age. The 1997 award will be given in condensed matter physics. Medal and prize of $10,000 awarded every four years for investigations in astronomical physics. Established through the Draper Fund by gift of Mrs. Henry Draper. Richard Lounsbery-Award First presented in 1886. Medal and prize of $50,000 awarded annually. Given in Recent recipients: alternate years to American and French scientists in 1971 S. Chandrasekhar recognition of extraordinary scientific achievement in 1974 Lyman Spitzer, Jr. biology and medicine, the award is intended to stimu- 1977 Arno Penzias late research and to encourage reciprocal scientific Robert W. Wilson exchanges between the United States and France. A 1980 W. W. Morgan further sum of $20,000 is provided to visit a laboratory 1985 Joseph H. Taylor, Jr. or research institution in France (if the recipient is 1989 Riccardo Giovanelli American) or in the United States (if the recipient is Martha P. Haynes French). American recipients are invited to lecture at a 1993 Ralph A. Alpher scientific meeting of the Academy. Established by Robert Herman Vera Lounsbery in memory of her husband, Richard

iv Lounsbery. The 1997 award will be given to an 1990 Elizabeth H. Blackburn American scientist. 1991 Steven L. McKnight Robert Tjian Recipients: 1992 Bruce S. Baker 1979 Michael S. Brown Thomas W. Cline Joseph L. Goldstein 1993 Peter S. Kim 1980 Frangois Morel 1994 Gerald F. Joyce 1981 Philip Leder Jack W. Szostak 1982 Pierre Chambon 1995 Daniel E. Gottschling Jean Pierre Changeux 1996 Michael S. Levine 1983 Giinter Blobel 1984 Maxime Schwartz 1985 Martin Gellert Thomas Maniatis NAS Award for Behavioral Research 1986 Andre Capron Relevant to the Prevention Jacques Glowinski of Nuclear War 1987 Alfred G. Gilman Martin Rodbell Prize of $15,000 awarded approximately every three 1988 Fran§ois Cuzin years to recognize basic research in any field of cogni- 1989 Richard Axel tive or behavioral science that has employed rigorous 1990 Jean Rosa formal or empirical methods, optimally a combination 1991 Marc W. Kirschner of these, to advance our understanding of problems or Harold Weintraub issues relating to the risk of nuclear war. Established 1992 Philippe Ascher by gift of William K. and Katherine W. Estes. Henri Korn 1993 Stanley B. Prusiner Recipients: Bert 1990 Robert Axelrod Vogelstein 1993 1994 Jean Louis Mandel Thomas C. Schelling 1995 Douglas A. Melton 1996 Daniel Louvard Jacques Pouysseur NAS Public Welfare Medal Medal awarded annually by the Council of the Academy in recognition of distinguished contributions NAS Award in Molecular Biology in the application of science to the public welfare. The -Supported by the Monsanto Company award was initially supported by the Marcellus Hartley Medal and prize of $20,000 presented annually for Fund. First nresented in 1914. recent notable discovery in molecular biology by a young scientist who is a citizen of the United States. Recent recipients: The award was supported by the U.S. Steel (now USX) 1980 Walter Sullivan Foundation from 1961 to 1988. 1981 Russell E. Train 1982 Paul G. Rogers Recent recipients: 1983 Mina Rees 1980 Phillip A. Sharp 1984 Theodore Hesburgh 1981 Ronald W. Davis 1985 I. I. Rabi Gerald R. Fink 1986 William D. Carey 1982 Joan A. Steitz 1987 Dale E. Corson 1983 James C. Wang 1988 John E. Sawyer 1984 Geoffrey M. Cooper 1989 David Packard Robert A. Weinberg 1990 C. Everett Koop 1985 Gerald M. Rubin 1991 Victor F. Weisskopf Allan C. Spradling 1992 Philip H. Abelson 1986 Robert G. Roeder 1993 Jerome B. Wiesner 1987 Thomas R. Cech 1994 Carl E. Sagan 1988 H. Robert Horvitz 1995 Harold Amos 1989 Kiyoshi Mizuuchi 1996 William T. Golden

v NAS Award for Scientific Reviewing Established by the bequest of Leonard T. Troland.

-Established by Annual Reviews, Inc. and the Institute Recipients: for Scientific Information in honor of J. Murray Luck

Prize of $5,000 awarded annually for excellence in sci- 1985 Keith D. White Ratcliff entific reviewing published anywhere. The field of the 1986 Roger award rotates among the biological, physical, and 1987 Laurence T. Maloney social sciences; the 1997 field is evolutionary biology. BrianuA.dWaselln ; 1988L0tEiric. Knudsen : 0;fLt:f0 ;; ; 1989 loan T. Cacioppo 1990 Robert Desimone Gilbert Morgan Smith Medal 1991 Daniel L. Schacter

awarded three Medal and prize of $15,000 every years 1992 SMartha Farah for excellence in published research on marine or 1993 Steven Pinker Established the Helen P. freshwater algae. through Donaldd. Hoffmand Smith Fund. David G. Lavond 1995 Michael S. Fanselow Recipients: Robert M. Nosofsky 1979 William R. Taylor 1996 Joseph E. Steinmetz 1982 Luigi Provasoli Steven G. Yantis 1985 Richard C. Starr 1988 Ruth Sager 1991 Jean-David Rochaix Selman A. Waksman Award 1994 Elisabeth Gantt in Microbiology Prize of $5,000 awarded biennially for excellence in the J. Lawrence Smith Medal field of microbiology. Contributed by the Foundation for Microbiology. First presented in 1968. Medal and prize of $20,000 awarded every three years for investigations of meteoric bodies. Established Recent recipients: through the Smith Fund by gift of Mrs. Sarah Julia 1980 Julius Adler Smith. First presented in 1888. 1982 Irwin C. Gunsalus 1984 Purnell W. Choppin Recent recipients: 1986 Harland G. Wood 1971 Edward Anders 1989 Bernard D. Davis 1973 Clair C. Patterson 1991 Melvin I. Simon 1976 John A. Wood 1993 Boris Magasanik 1979 Ralph B. Baldwin 1995 Ralph S. Wolfe 1985 Gerald J. Wasserburg 1988 Alastair G. W. Cameron 1991 Robert M. Walker Charles Doolittle Walcott Medal 1994 Donald E. Brownlee Medal and prize of $2,000 awarded not more often than once every five years to stimulate research in pre- Troland Research Awards Cambrian and Cambrian life and history. Established through the Walcott Fund by gift of Mrs. Mary Vaux Two awards of $35,000 each awarded annually to young Walcott. First presented in 1934. investigators (age 40 or younger) to recognize unusual achievement and further empirical research in psychol- Recent recipients: ogy regarding the relationships of consciousness and 1972 Elso S. Barghoorn the physical world. Funds are to be used by the 1977 Preston Cloud awardee for research within the broad spectrum of 1982 Martin F. Glaessner experimental psychology, including, for example, the 1987 Andrew H. Knoll topics of sensation, perception, motivation, emotion, Simon Conway Morris learning, memory, cognition, language, and action. 1992 Stefan Bengtson

vi LSLA I. Si *!IA

NATIONAL ACADEMY OF SCIENCES AWARDS 1997

NAME OF AWARD:

Nomination Form (Please type or print) Please provide the following supporting material with this form: - the candidate's curriculum vitae - a one- to two-page summary of the candidate's achievements - a selected bibliography of no more than twelve items

1. CANDIDATE'S NAME: Last First M.I. Date of Birth Citizenship

2. ADDITIONAL CANDIDATE(S) FOR JOINT NOMINATION (Please answer 1-4 on a separate sheet for each):

3. POSITION AND AFFILIATION (include complete mailing address and telephone number):

4. HOME ADDRESS (include complete mailing address and telephone number):

PROPOSED CITATION (25-word statement of scientific contribution meriting this award: "For his/her/their ...

NOMINATOR (include name, title, organization, address, and telephone number):

Nominator's Signature

SUPPORTING LETTERS ARE BEING REQUESTED FROM THE FOLLOWING INDIVIDUALS (optional):

(1) (4) (2) (5) (3) (6)

All nomination form(s), summary of accomplishments, selected bibliography, and supporting letters must be received no later than September 1, 1996.

Mail to: National Academy of Sciences Telephone: (202) 334-2444 Office of the Home Secretary, Room 185 FAX: (202) 334-2153 2101 Constitution Avenue, NW Internet: [email protected] Washington, DC 20418

vii =~A~!I I

Alexander Agassiz Medal NAS Award for the Industrial Medal and prize of $6,000 awarded every three years for Application of Science an original contribution in the science of oceanogra- Prize of $25,000 awarded every three years for original phy. Last presented in 1995. scientific work of intrinsic scientific importance and with significant, beneficial applications in industry. Arctowski Medal Established by the IBM Corporation in honor of Ralph Medal and prize of $20,000, plus $60,000 to an institu- E. Gomory. Last presented in 1996. tion of the recipient's choice, awarded approximately every three years for studies in solar physics and solar- NAS Award in Mathematics terrestrial relationships. Last presented in 1996. Prize of $5,000 awarded every four years for excellence of research in the mathematical sciences published Comstock Prize within the past ten years. Established by the American Prize of $20,000 awarded every three years for a most Mathematical Society in commemoration of its centen- important discovery or investigation in electricity, mag- nial. Last presented in 1996. netism, or radiant energy; to be given to a resident of North America. Last presented in 1995. NAS Award in the Neurosciences Medal and prize of $15,000 awarded approximately Arthur L. Day Prize and Lectureship every three years for extraordinary contributions to Prize of $20,000 awarded approximately every three progress in the fields of neuroscience, including neuro- years to a scientist making new contributions to the chemistry, neurophysiology, neuropharmacology, physics of the earth whose four to six lectures would developmental neuroscience, neuroanatomy, and prove a solid, timely, and useful addition to the knowl- behavioral and clinical neuroscience. Established by edge and literature in the field. Last presented in 1996. the Fidia Research Foundation. Last presented in 1994. Daniel Giraud Elliot Medal Medal and prize of $5,000 awarded every three to five Robertson Memorial Lecture of the years for meritorious work in zoology or paleontology. National Academy of Sciences Last in 1996. presented Prize of $7,500 awarded every three years to a distin- guished scientist from anywhere in the world. The Jessie Stevenson Kovelenko Medal recipient is invited to lecture on his or her work and its Medal and prize awarded approximately every three international aspects. Last presented in 1996. years for important contributions to the medical sci- ences. Last presented in 1994. Mary Clark Thompson Medal Medal and prize of $7,500 awarded every three to five NAS Award in Aeronautical years for most important service to geology and pale- Engineering ontology. Last presented in 1995. Prize of $15,000 awarded once every five years for excel- lence in the field of aeronautical engineering. Last G. K. Warren Prize presented in 1995. Prize of $6,000 awarded approximately every four years for noteworthy and distinguished accomplishment in NAS Award in Applied Mathematics fluviatile geology and closely related aspects of the and Numerical Analysis geological sciences. Last presented in 1994. Prize of $10,000 awarded every three years for out- standing work in applied mathematics and numerical James Craig Watson Medal analysis by a candidate whose research has been car- Medal and prize of $15,000 awarded approximately ried out in institutions located in North America. every three years for contributions to the science of Established by the IBM Corporation. Last presented in astronomy. Last presented in 1994. 1995.

viii AUTHOR INDEX, JUNE 25, 1996

Abdel-Malek, S. 6326 Chorin, A. J. 6749 Flores-Rozas, H. 6521 Aderem, A. 6275 Choudhary, A. 6786 Flynn, L. M. 6393 Akoulitchev, S. 6488 Chow, S. A. 6326 Ford, M. J. 6291 Alewijnse, A. E. 6802 Clark, A. J. 6659 Forsberg, E. 6594 Alexianu, M. E. 6796 Clark, D. 6464 Franceschi, C. 6458 Altland, K. 6302 Clark, T. G. 6825 Francois, D. 6458 Anderson, C. J. 6814 Clegg, C. H. 6605 Frohlich, L. 6594 Anderson, M. J. 6665 Clore, G. M. 6846 Fujii, Y. 6236 Appel, S. H. 6796 Cockcroft, S. 6589 Fujikawa, K. 6258 Aranson, I. 6382, 6382 Cohen, Y. 6338 Fulton, A. M. 6399 Aszodi, A. 6594 Colbert, M. C. 6258 Fumihito, A. 6792 Ault, K. T. 6415 Collier, M. L. 6343 Furman-Haran, E. 6247 Bacher, A. 6431 Collins, J. L. 6687 Furukawa, K. 6753 Bachman, E. S. 6808 Colom, L. V. 6796 Gadgil, M. 6387 Back, K. 6841 Conejero, V. 6332 Galbreath, E. J. 6361 Baergen, R. N. 6704 Connett, J. M. 6814 Gallily, T. 6470 Baggiolini, M. 6682 Cossarizza, A. 6458 Ganem, D. 6641 Bankaitis, V. 6589 Cowland, J. B. 6454 Garcia-Cardefia, G. 6448 Barenblatt, G. I. 6749 Crowe, J. H. 6835 Garen, A. 6280 Barger, S. W. 6753 Crowe, L. M. 6835 Garrett, C. L. 6297 Baumann, P. 6726 Cruz, S. S. 6286 Ge, H. 6482 Behringer, R. R. 6361 Cunningham, E. 6589 Geary, Y. 6343 Ben-Sasson, S. A. 6470 Danton, M. J. S. 6258 Gee, M. A. 6552 Bernstein, S. L. 6410 Darnell, J. E., Jr. 6221 Ghilardi, N. 6231 Bian, Z. 6562 Davidson, E. H. 6759 Ghirlando, R. 6846 Bidochka, M. J. 6349 Davie, E. W. 6258 Gibbs, E. 6482 Biemann, K. 6626 Davis, S. R. 6698 Gilman, A. G. 6621 Birger, Y. 6371 Dawson, T. M. 6770 Goeddel, D. V. 6721 Birren, B. W. 6297 Dawson, V. L. 6770 Gojobori, T. 6792 Bister, K. 6635 Dean, F. B. 6521 Goodman, M. 6510 Bjorklund, A. 6355 Dean, W. L. 6371 Goto, N. K. 6676 Blanc, E. M. 6753 Deber, C. M. 6676 Graham, E. 6659 Blatzinger, P. 6302 Degani, H. 6247 Greene, M. I. 6252 Blauw, J. 6802 Degen, J. L. 6258 Gregg, R. G. 6361 Blobel, G. 6572 Delaney, C. L. 6361 Grobgeld, D. 6247 Blumberg, B. S. 6542 DeLong, E. F. 6241 Gronenborn, A. M. 6846 Borregaard, N. 6454 Denzel, K. 6302 Grota, K. 6291 Borst, P. 6743 Der, C. J. 6665 Gu, G. 6577 Boukamp, P. 6476 Derenyi, I. 6775 Gumucio, D. L. 6510 Bowers, F. S. 6653 Dessauer, C. W. 6621 Guo, L.-W. 6814 Bradfield, C. A. 6731 Dickerson, H. W. 6825 Ha, T. 6264 Brady, J. 6377 Din, N. 6314 Haig, D. 6547 Brahamsha, B. 6504 Dirksen, M.-L. 6415 Hajimohammadreza, I. 6687 Brennan, P. J. 6252 Dobie, K. W. 6659 Hammar, M. 6562 Brenner, M. 6361 Dow, W. C. 6610 Hampton, G. M. 6704 Brenner, M. B. 6567 Drapkin, R. 6488 Hanin, L. G. 6671 Brindle, K. M. 6399 Drenckhahn, D. 6631 Hanson, J. M. 6425 Brumblay, H. G. 6693 Drummond, J. T. 6443 Hao, Y. 6610 Brun, Y. V. 6314 Dube, P. 6764 Harle-Bachor, C. 6476 Bugge, T. H. 6258 Duckett, D. R. 6443 Harriman, A. 6610 Bugos, R. C. 6320 Duncan, S. A. 6275 Hart, P. 6343 Buroker-Kilgore, M. 6687 Dunham, I. 6297 Hartwig, W. C. 6405 Cai, J. 6521 Ebendal, T. 6355 Hatanaka, M. 6687 Cai, X. 6280 Edelmann, W. 6225 Hays, L. M. 6835 Calafat, J. 6454 Edman, L. 6710 Hays, S. J. 6687 Caldwell, G. A. 6577 Ehrlich, S. D. 6647 Heim, M. H. 6231 Cameron, R. A. 6759 Eisenreich, W. 6431 Hemmi, G. W. 6610 Canceill, D. 6647 Eisner, M. 6494, 6499 Herndier, B. 6641 Caner, H. 6687 Eisner, T. 6494, 6499 Higgins, D. W. 6780 Carmel, G. 6308 Ekblom, P. 6594 Hinds, P. W., II 6425 Cartelle, C. 6405 Emiliani, S. 6377 Hirsch, E. 6594 Cavenee, W. K. 6704 Enderle, T. 6264 Ho, B.-K. 6796 Cepek, K. L. 6567 Endo, T. 6792 Hofer, D. 6631 Chak, K.-F. 6437 Essex, M. 6693 Holmback, K. 6258 Chalfie, M. 6577 Evers, R. 6743 Horowitz, B. 6343 Cham, C. M. 6393 Fantes, J. A. 6659 Hsieh, C.-C. 6693 Chang, S. 6275 Farese, R. V., Jr. 6393 Hsieh, S.-Y. 6437 Chapman, S. 6286 Fasching, C. L. 6665 Hsu, D. K. 6737 Chappell, J. 6841 Fassler, R. 6594 Hsuan, J. 6589 Chemla, D. S. 6264 Feeney, R. E. 6835 Hume, J. R. 6343 Chen, J. 6275 Felsenfeld, G. 6846 Hurwitz, J. 6482, 6521 Cheng, X. 6308 Fergus, A. 6687 Huszar, D. 6393 Chitnis, P. R. 6338 Finkelstein, J. 6521 Hutchinson, C. R. 6600 Chiu, C.-h. 6510 Fischer, W. 6355 Hylands, P. J. 6431 Chiu, S. Y. 6361 Fischle, W. 6377 Ikeda, T. P. 6527 Cho, H. 6488 Fishell, G. 6275 Imokawa, Y. 6819 Choi, S.-S. 6297 Flick, M. J. 6258 Jackson, S. P. 6726

xv AUTHOR INDEX, JUNE 25, 1996

Jamrich, M. 6415 Mayer, K. H. 6693 Rabinowitz, J. E. 6421 Jenne, D. E. 6302 Mazumdar, M. 6552 Rachev, S. T. 6671 Jia, Q. 6326 Meinwald, J. 6494, 6499 Radu, A. 6572 Jones, S. A. 6682 Meireles, C. 6510 Rakhmilevich, A. L. 6291 Joshi, L. 6349 Mencia, M. 6616 Ransick, A. 6759 Joshi, N. V. 6387 Menhard, B. 6431 Raser, K. J. 6687 Jung, K.-H. 6557 Mercier, J.-C. 6698 Razin, A. 6371 Kang, H.-L. 6297 Merino, A. 6583 Reardon, J. T. 6443, 6482 Kanno, R. 6516 Messing, A. 6361 Reddy, J. K. 6731 Kantengwa, S. 6458 Mets, U. 6710 Reik, W. 6371 Kelly, J. F. 6753 Meyer, M. 6594 Reinberg, D. 6488, 6583 Kempner, E. 6410 Mikami, A. 6552 Reinecke, M. G. 6326 Kern, S. 6704 Miller, R. A. 6610 Rengen, M. R. 6753 Kieber-Emmons, T. 6252 Minai, L. 6338 Riggs, A. D. 6371 Kim, U.-J. 6297 Mink, S. 6635 Rigler, R. 6710 Kimbrough, T. G. 6605 Mitra, A. 6780 Rimm, D. L. 6567 Kindt, T. J. 6653 Miyake, T. 6792 Roach, B. 6494, 6499 Kirzhner, V. M. 6532 Miyazaki, K. 6819 Roberts, A. G. 6286 Klempnauer, K.-H. 6635 Modrich, P. 6443 Roberts, D. W. 6349 Kombrinck, K. W. 6258 Mody, T. D. 6610 Roberts, I. M. 6286 Kondo, N. 6792 Mohamed, A. H. 6796 Robinson, M. A. 6653 Konopka, J. B. 6764 Molinski, T. F. 6241 Robinson, W. E., Jr. 6326 Korenberg, J. R. 6297 Monsalve, M. 6616 Rogers, B. E. 6814 Korol, A. B. 6532 Morita, T. 6236 Rojo, F. 6616 Koseki, H. 6516 Mornet, C. 6743 Roovers, E. 6802 Ku, W.-Y. 6437 Moroianu, J. 6572 Roth, G. S. 6753 Kucherlapati, R. 6225 Murali, R. 6252 Rothe, M. 6721 Kuret, J. 6308 Murchie, A. I. H. 6443 Ruland, S. 6393 Kustu, S. 6527 Mutschler, B. 6635 Rutin, J. 6269 Lan, M. S. 6367 Nadir, E. 6470 Rutishauser, U. 6421 Langenberg, W. G. 6780 Nakao, K. 6236 Safo, M. K. 6437 Larson, A. A. 6704 Nath, R. 6687 St. Leger, R. J. 6349 Lathe, R. 6659 Nathans, D. 6716 Sakumi, K. 6236 Le Cabec, V. 6454 Navas, P. A. 6605 Salas, M. 6616 Ledvina, P. S. 6786 Nechushtai, R. 6338 Salvioli, S. 6458 Lee, K. S. 6687 Nevo, E. 6532 Sampaio, I. 6510 Lee, M. 6659 Nie, H. 6780 Sancar, A. 6443, 6482 Lee, T.-H. 6693 Normark, S. 6562 Sato, K. Y. 6665 Lepourry, L. 6698 Norton, E. J. 6605 Scharko, A. M. 6425 Le Roy, G. 6488 Notkins, A. L. 6367 Schinkel, A. H. 6743 Leurs, R. 6802 Nowak, M. A. 6542 Schmidt, J. V. 6731 Levesque, P. C. 6343 Obermaier, B. 6302 Schneider, H. 6510 Levi, D. M. 6830 O'Donnell, M. 6521 Schneider, M. P. C. 6510 Levine, H. 6382, 6382 Ogletree, D. F. 6264 Schnitzer, J. E. 6448 Leyden, J. J. 6626 Oh, P. 6448 Schwarz, S. W. 6814 L'Huillier, P. J. 6698 Ohno, S. 6792 Seage, G. 6693 Li, E. 6464 Okano, H. J. 6275 Sekiguchi, M. 6236 Li, S.-C. 6676 Olave, I. 6583 Selvin, P. R. 6264 Lilley, D. M. J. 6443 Oliver, A. E. 6835 Sengupta, D. N. 6780 Lin, T.-L. 6825 Omichinski, J. G. 6846 Serrano, F. 6796 Linke, R. P. 6302 Oparka, K. J. 6286 Sessa, W. C. 6448 Liu, F.-T. 6737 Ott, M. 6377 Sessler, J. L. 6610 Liu, J. 6448 Pan, Z.-Q. 6482 Shauger, A. E. 6527 Loring, J. F. 6393 Paras, P., Jr. 6377 Sheldon, J. G. 6399 Lunney, E. A. 6687 Patil, S. 6387 Shemer, R. 6371 Ma, D. 6583 Pauza, C. D. 6425 Shen, B. 6600 McCabe, D. 6291 Payne, R. J. H. 6542 Shingu, R. 6792 McCall, M. A. 6361 Pearce, R. A. 6361 Shizuya, H. 6297 McClay, D. R. 6808 Pedone, P. V. 6846 Siegel, B. A. 6814 McClenaghan, M. 6659 Perlman, S. B. 6425 Silverman, R. H. 6780 Mackay, C. R. 6682 Pessac, B. 6269 Simon, M. C. 6731 McLane, M. F. 6693 Peterson, K. R. 6605 Simon, M. I. 6228, 6297 Maclaren, N. K. 6367 Philpott, G. W. 6814 Skoda, R. C. 6231 Magnuson, T. 6421 Pierotti, V. 6393 Slightom, J. L. 6510 Maher, J. F. 6716 Plattner, R. 6665 Smedley, S. R. 6494, 6499 Maki, M. 6687 Polat, U. 6830 Smink, L. J. 6297 Makino, Y. 6516 Polla, B. S. 6458 Smit, M. J. 6802 Marcoux, F. W. 6687 Posner, A. 6687 Snyder, S. H. 6770 Margalit, H. 6470 Preston, C. M. 6241 Soderstrom, S. 6355 Margalit, R. 6247 Preti, G. 6626 Sommers, R. L. 6704 Margarit, S. M. 6764 Prior, D. A. M. 6286 Sondel, P. M. 6291 Mark, R. J. 6753 Probert, A. W., Jr. 6687 Song, H. Y. 6721 Marsac, C. 6458 Puschel, B. 6631 Soulier, S. 6698 Martinez-Serrano, A. 6355 Qin, S. 6682 Spielman, A. I. 6626 Martinoia, E. 6743 Qing, F. 6610 Springbett, A. 6659 Matsushiro, A. 6236 Quardokus, E. 6314 Spudich, J. L. 6557 Mattson, M. P. 6753 Quiocho, F. A. 6786 Stamatoyannopoulos, G. 6605 xvi AUTHOR INDEX, JUNE 25, 1996

Stanbridge, E. J. 6665 Van De Vrede, Y. 6802 Xia, Y. 6770 Stanley, S. L., Jr 6464 Van Lint, C. 6377 Xiao, Q. 6258 Stein, J. L. 6228 Van Nieuw Amerongen, G. P. 6802 Xu, R.-M. 6308 Stinnakre, M.-G. 6698 Veniant, M. M. 6393 Yakovlev, A. Y. 6671 Stoffel, R. 6231 Vera, P. 6332 Yamamoto, H. Y. 6320 Stokowski, R. S. 6393 Verdin, E. 6377 Yan, D. 6527 Su, G. H.-T. 6731 Vermeulen, R. C. 6846 Yang, N.-S. 6291 Sun, W. H. 6291 Vicsek, T. 6775 Yang; R.-Y. 6737 Swigart, P. 6589 Vilotte, J.-L. 6698 Yao, N. 6786 Takada, M. 6792 Vogt, E. 6743 Ye, Q. 6687 Takano, E. 6687 Vowels, B. R. 6626 Yong, T.-S. 6464 Tan, S. K. 6589 Wang, H. 6641 Yoshimura, Y. 6236 Taniguchi, M. 6516 Wang, K. K. W. 6687 Yoshizato, K. 6819 Timmerman, H. 6802 Wang, W.-K. 6693 Young, D. K. 6494, 6499 Tominaga, Y. 6236 Warth, J. D. 6343 Young, S. G. 6393 Tommasini, R. 6743 Wasserfall, C. 6367 Young, S. W. 6610 Tornero, P. 6332 Weiskirchen, R. 6635 Yuan, H. S. 6437 Traber, M. 6393 Weiss, S. 6264 Yuen, P.-w. 6687 Trisler, D. 6269 Welch, M. J. 6814 Zaman, G. J. R. 6743 Truong, T. V. 6382, 6382 Werner, S. 6594 Zaphiropoulos, P. G. 6536 Tsimring, L. 6382, 6382 Whisnant, R. E. 6621 Zeng, C. 6626 Tsodikov, A. D. 6671 Wiestner, A. 6231 Zenk, M. H. 6431 Tsuzuki, T. 6236 Williams, K. A. 6676 Zhang, C. L. 6361 Turner, J. 6291 Williams, S.-P. 6399 Zhao, T. M. 6653 Uchiyama, K. 6819 Winter, P. 6302 Zhong, W. 6641 Uhlmann, F. 6521 Witte, D. P. 6258 Ziegler, S. 6231 Uno, H. 6425 Wolf, M. 6682 Zinn, K. R. 6814 Vallee, R. B. 6552 Wu, K. Y. 6241 Zweier, J. L. 6770

xvii The Proceedings of the National Academy of Sciences (PNAS) is seeking a managing editor and a business operations manager.

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