22 



NOTICE; The project that is the subject of this repon was approved by the Governing Board of the 

 National Research Council, whose members are drawn from the councils of the National Academy of 

 Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the 

 committee responsible for the report were chosen for their special competences and with regard for 

 appropriate balance. 



This repon has been reviewed by a group other than the authors according to procedures 

 approved by a Repon Review Committee consisting of members of the National Academi,' of Sciences, the 

 National Academy of Engineering, and the Institute of Medicine. 



The National Academy of Sciences is a private, nonprofit, self-perpetuating socien- of distin- 

 guished scholars engaged in scientific and engineering research, dedicated to the furtherance of science 

 and technology' and to their use for the general welfare. Upon the authorit>' of the chaner granted to it b> 

 the Congress in 1863. the Academy has a mandate that requires it to advise the federal government on 

 scientific and technical maners. Dr Bruce Alberts is president of the National Academ>- of Sciences. 



The National Academy of Engineering was established in 1964, under the chaner of the National 

 Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its admini^- 

 tration and in the selection of its members, sharing with the National Academy of Sciences the responsibil- 

 if)' for advising the federal government. The National Academy of Engineering also sponsors engineering 

 programs aimed at meeting national needs, encourages education and research, and recognizes the 

 superior achievements of engineers. Dr Harold Liebowitz is president of the National Academy of 

 Engineering. 



The Institute of Medicine was established in 1970 by the National Academy of Sciences to 

 secure the services of eminent members of appropriate professions in the examination of policy matters 

 pertaining to the health of the public. The Institute acts under the responsibilin' given to the National 

 Academy of Sciences by its congressional charter to be an adviser to the federal government and. upon its 

 own initiative, to identifi,' issues of medical care, research, and education. Dr Kenneth I. Shine is presi- 

 dent of the Institute of Medicine. 



The National Research Council was established by the National Academy of Sciences in 1916 to 

 associate the broad communin- of science and technology with the Academy's purposes of furthering 

 knowledge and advising the federal government. Functioning in accordance with general policies 

 determined by the Academy, the Council has become the principal operating agency of both the National 

 Academy of Sciences and the National Academy of Engineering in providing services to the government, 

 the public, and the scientific and engineering communities. The Council is administered jointly by both 

 Academies and the Institute of Medicine. Dr Bruce Alberts and Dr. Harold Liebowitz are chairman and 

 vice chairman, respectively, of the National Research Council. 



Support for this project was provided by the Department of Defense (under Contract No. 

 N00014-95-C-0314), the National Institutes of Health (under Contract No. N01-OD-+-2139,Task Order =4), 

 the National Science Foundation (under Grant No. OPS-9528889), and the Basic Science Fund of the 

 National Academy of Sciences. Any opinions, findings, and conclusions or recommendations expressed in 

 this material are those of the authors and do not necessarily reflect the views of the National Science 

 Foundation. 



Librar>' of Congress Catalog Card Number 95-71602 

 International Standard Book Number 0-309-05347-1 



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