GENERAL INFORMATION

The guidelines below describe our manuscript selection, review, and publication process. Please follow these guidelines in preparing your manuscript to ensure speedy handling by our editorial offices.

General articles should include a note giving the authors' names, titles, and addresses; an abstract (50 to 100 words); an introduction that outlines for the general reader the main point of the article; and brief subheadings to indicate the main ideas. The reference list should not be exhaustive; a maximum of 50 references is suggested.

RESEARCH ARTICLES(up to 4000 words total or four printed pages) are expected to contain new data representing a major breakthrough in a field. The article should include an author note, abstract, introduction, and sections with brief subheadings.

A maximum of 40 references is suggested.

FIGURES AND TABLES TOGETHER WITH THEIR LEGENDS SHOULD OCCUPY ABOUT ONE PRINTED PAGE FOR GENERAL ARTICLES AND RESEARCH ARTICLES.

REPORTS (up to 2500 words total or three printed pages) are expected to contain important research results. Addresses for all authors should be listed on the title page and the corresponding author should be indicated by an asterisk. Reports should include an abstract (no more than 100 words) and an introductory paragraph. A maximum of 30 references is suggested. FIGURES AND TABLES TOGETHER WITH THEIR LEGENDS SHOULD OCCUPY NO MORE THAN THREE-QUARTERS OF A PRINTED PAGE.

POLICY FORUM (up to 2000 words total or two printed pages) provides a platform to present discussions of policy issues relevant to science.

PERSPECTIVES briefly analyze recent research and the impact of new developments on future investigations, rather than present new results and hypotheses, and should not primarily discuss the author's own work. Perspectives are limited to between one and two printed pages.

LETTERS are selected for their pertinence to material published in SCiENCE or because they discuss problems of general interest to scientists. Letters about material published in SCiENCE may

MANUSCRIPT PREPARATION

Use double-spacing throughout the text, tables, figure legends, and references and notes, and leave margins of at least 2.5 centimeters. Put your name on each page and number the pages starting with the title page.

TITLES AND SUBHEADINGS should be descriptive clauses, not complete sentences or questions. The maximum length is 102 characters and spaces for general articles, and 98 characters and spaces for research articles and reports.

ABSTRACTS should explain to the general reader why the research was undertaken and why the results should be viewed as important. The abstract should convey the paper's main point and outline the results or conclusions.

TEXT. A brief introduction describing the paper's significance should be intelligible to readers in different disciplines. Technical terms should be defined. All tables and figures should be cited in numerical order.

FIGURES AND TABLES should be submitted on separate pages from the text. For each figure submit four high-quality prints, laser prints, or original drawings no larger than 22 by 28 centimeters (8 1/2 by 11 inches). On the back of every figure write the first author's name and the figure number and indicate the correct orientation.

Photocopies of figures are not acceptable; transparencies, slides, or negatives cannot be used because they cannot be sent to reviewers. Papers that include a large number of figures or tables and a small amount of text may present layout problems. In preparing the manuscript, try to maintain sufficient text to wrap around the figures.

On acceptance of a paper, authors requesting the use of color will be required to pay $650 for the first color figure and $450 for each additional figure or figure part to help defray costs relating to publishing color. There will be an additional charge for color figures in the reprints.

COVER ILLUSTRATION suggestions may be included with the manuscript. Submit prints, not slides, negatives, or transparencies. After an image is chosen for use on the cover, a positive transparency will be required.

INFORMED CONSENT. Investigations on humans must include a statement indicating that informed consent was obtained after the nature and possible consequences of the studies were explained.

ANIMAL WELFARE. Authors using experimental animals must include a statement that their care was in accordance with institutional guidelines. For animals subjected to invasive procedures, include the anesthetic, analgesic, and tranquilizing agents used, as well as the amounts and frequency of administration.

UNCERTAINTIES AND REPRODUCIBILITY. Evidence that the results are reproducible and the conditions under which this reproducibility (replication) was obtained should be explicitly stated. The effect of limitations in experimental conditions on generalizability of results should be discussed. Uncertainties should be stated in terms of variation expected in independent repetitions of the experiments; they should include an allowance for possible systematic error arising from inadequacies in the assumed model and other known sources of possible bias. Probabilities from statistical tests of significance should not replace the reporting of results and associated uncertainties.

PERMISSIONS TO REPRINT illustrations or tables from other publications must be obtained in writing by the author. The written permission must include complete citation from the copyright owner (usually the publisher) to reprint such illustrations in SCiENCE. Papers are not sent to the printer until copies of all permission letters have been received.

COPYRIGHT law requires that we obtain copyright transfer from authors of each paper published in SCiENCE. Copyright forms are sent to all authors prior to acceptance and must be signed and returned to the Washington, D.C., editorial office immediately. U.S. government employees sign the section of the form stating exemption from copyright laws. Alterations to or substitutions for our form are not acceptable. correct errors, provide support or agreement, or offer different points of view, clarifications, or additional information. Personal remarks about an author are inappropriate. Letters may be reviewed. Those selected for publication are intended to reflect the range of opinions received. The author of the paper in question is usually given an opportunity to reply. All letters are acknowledged by postcard; authors are notified if their letters are to be published. Preference is given to short letters (250-500 words). Letters accepted for publication are frequently edited and shortened in consultation with the author.

TECHNICAL COMMENTS (up to 500 words) may criticize articles or reports published in SCiENCE within the previous 6 months or may offer useful additional information. Minor issues should be resolved by private correspondence. The authors of the original paper are asked for an opinion of the comment and are given an opportunity to reply in the same issue if the comment is published. Comments and replies are subject to the usual reviewing and editing procedures. Priority disputes may undergo extensive review and are published only when action is recommended.

BOOK REVIEW selections are made by the editors. Instructions and length specifications accompany items to be reviewed when they are sent to the reviewers, who are chosen by the editors.

CHECKLIST FOR SUBMISSION

Manuscripts should be addressed to the

Editor-in-Chief, SCiENCE,

1333 H Street, NW, Washington, DC 20005

or to the

Senior editor, European Office

Thomas House

George IV St., Cambridge CB21NH, UK.

Submit four copies together with a letter giving:

the names and telephone numbers of the authors, and the fax number and electronic mail address of the corresponding author.

the title of the paper and a statement of its main point.

the names, addresses (including electronic mail addresses), telephone and fax numbers, and fields of interest of four to six persons outside your institution who are qualified to referee the paper. Also, please include any information needed to ensure a fair review process and to avoid potential conflicts of interest.

the names of colleagues who have reviewed the paper.

the total number of words (including text, references, and figure and table legends) in the manuscript.

a statement regarding whether any of the material has been published or is under consideration for publication elsewhere.

Also include with your manuscript:

any paper of yours that is in press or under consideration elsewhere and includes information that would be helpful in evaluating the work submitted to SCiENCE.

written permission from any author whose work is cited as a personal communication, unpublished work, or work in press but is not an author of your manuscript.

for manuscripts based on crystallographic data, two copies of the coordinates.

any information about the authors' professional and financial affiliations that may be perceived to have biased the presentation.

CONDITIONS OF ACCEPTANCE

When a paper is accepted for publication in SCiENCE, it is understood that any materials and methods necessary to verify the conclusions of the experiments reported will be made available to other investigators under appropriate conditions.

archival data sets (such as sequence and crystallographic data) will be offered for deposit to the appropriate data bank and the identifier code will be sent to SCiENCE for inclusion in the published manuscript (coordinates should be released no later than 1 year after publication).

the author or authors agree to transfer copyright of the paper to SCiENCE; and the paper will remain a privileged document and will not be released to the press or the public before publication.

if there is a need in exceptional cases to publicize data in advance of publication, the AAAS Office of Communications (202-326-6440) must be consulted.

MANUSCRIPT PREPARATION

Use double-spacing throughout the text, tables, figure legends, and references and notes, and leave margins of at least 2.5 centimeters. Put your name on each page and number the pages starting with the title page.

TITLES AND SUBHEADINGS should be descriptive clauses, not complete sentences or questions. The maximum length is 102 characters and spaces for general articles, and 98 characters and spaces for research articles and reports.

ABSTRACTS should explain to the general reader why the research was undertaken and why the results should be viewed as important. The abstract should convey the paper's main point and outline the results or conclusions.

TEXT. A brief introduction describing the paper's significance should be intelligible to readers in different disciplines. Technical terms should be defined. All tables and figures should be cited in numerical order.

FIGURES AND TABLES should be submitted on separate pages from the text. For each figure submit four high-quality prints, laser prints, or original drawings no larger than 22 by 28 centimeters (8 1/2 by 11 inches). On the back of every figure write the first author's name and the figure number and indicate the correct orientation.

Photocopies of figures are not acceptable; transparencies, slides, or negatives cannot be used because they cannot be sent to reviewers. Papers that include a large number of figures or tables and a small amount of text may present layout problems. In preparing the manuscript, try to maintain sufficient text to wrap around the figures.

On acceptance of a paper, authors requesting the use of color will be required to pay $650 for the first color figure and $450 for each additional figure or figure part to help defray costs relating to publishing color. There will be an additional charge for color figures in the reprints.

COVER ILLUSTRATION suggestions may be included with the manuscript. Submit prints, not slides, negatives, or transparencies. After an image is chosen for use on the cover, a positive transparency will be required.

INFORMED CONSENT. Investigations on humans must include a statement indicating that informed consent was obtained after the nature and possible consequences of the studies were explained.

ANIMAL WELFARE. Authors using experimental animals must include a statement that their care was in accordance with institutional guidelines. For animals subjected to invasive procedures, include the anesthetic, analgesic, and tranquilizing agents used, as well as the amounts and frequency of administration.

UNCERTAINTIES AND REPRODUCIBILITY. Evidence that the results are reproducible and the conditions under which this reproducibility (replication) was obtained should be explicitly stated. The effect of limitations in experimental conditions on generalizability of results should be discussed. Uncertainties should be stated in terms of variation expected in independent repetitions of the experiments; they should include an allowance for possible systematic error arising from inadequacies in the assumed model and other known sources of possible bias. Probabilities from statistical tests of significance should not replace the reporting of results and associated uncertainties.

PERMISSIONS TO REPRINT illustrations or tables from other publications must be obtained in writing by the author. The written permission must include complete citation from the copyright owner (usually the publisher) to reprint such illustrations in SCiENCE. Papers are not sent to the printer until copies of all permission letters have been received.

COPYRIGHT law requires that we obtain copyright transfer from authors of each paper published in SCiENCE. Copyright forms are sent to all authors prior to acceptance and must be signed and returned to the Washington, D.C., editorial office immediately. U.S. government employees sign the section of the form stating exemption from copyright laws. Alterations to or substitutions for our form are not acceptable.

MANUSCRIPT REVIEW AND SELECTION

Before being reviewed in depth, most papers are rated for their interest and overall suitability by members of the Board of Reviewing Editors. Papers submitted in disciplines for which there is no appropriate member of the Board of Reviewing Editors may be screened by editorial staff in consultation with outside experts. Papers that are not highly rated are mailed back to the authors within about 2 weeks; the title page and abstract from one copy are retained for our files.

Approximately 35% of submitted papers are reviewed in depth by two or more outside referees. Reviewers are telephoned prior to being sent a paper and are expected to decline to review if they are not qualified or if there is a possible conflict of interest. Reviewers are expected to return their comments within 2 weeks and are instructed that the manuscript is a privileged document that is not to be disseminated or exploited. It is the policy of SCiENCE that reviewers are kept anonymous.

During the review process, the author may be required to submit to SCiENCE any computer programs by which the results presented in the manuscript were obtained if such programs are essential to replicating the data and are requested by a reviewer or editor.

When the review process is complete, the manuscript and reviewers' comments are discussed by the editors at a weekly meeting. Manuscripts are evaluated in terms of their technical merit as well as their merit in relation to other papers that are or have been considered.

In selecting papers for publication, the editors give preference to those of novelty and general significance that are well written, well organized, and intelligible to scientists in different disciplines. An attempt is made to balance the subject matter in all sections of SCiENCE. Membership in the AAAS is not a factor in selection.

Authors are notified of acceptance, rejection, or need for revision, usually within 8 to 10 weeks. Accepted papers are edited to improve accuracy and clarity and to bring them within the specified length limits.

Papers cannot be resubmitted over a disagreement on interest level or relative merit. If the author can demonstrate that a paper was rejected on the basis of serious reviewer error, resubmission will be considered.

PRINTING AND PUBLICATION

PROOFS AND REPRINTS. One set of proofs and an order blank for reprints are sent to the authors. All corrections should be marked on the author proof.

SCHEDULING. Papers are scheduled for publication after SCiENCE has received corrected proofs. Papers with tables or figures that present problems in layout, or with cover pictures, or that exceed the length limits may be subject to delay.

SCiENCE STYLE

ACKNOWLEDGEMENTS, including funding information, should be gathered into a brief statement at the end of the references and notes and will be edited to conform to SCiENCE style.

EQUATIONS AND FORMULAS should be typed with quadruple-spacing if they are to be set off from the text. Define all symbols and number all equations.

FIGURES. Most figures will be printed at a width of 5.9 cm (2.3 inches or 1 column) or 12.2 cm (4.8 inches or 2 columns). Some illustrations (for example, bar graphs, simple line graphs, and gels) may be reduced to a smaller width. Symbols and lettering should be large enough to be legible after reduction. Composite figures should be labeled A,B,C,.... If mounting is necessary, use cardboard.

LEGENDS should be typed double-spaced in numerical order on a separate page. No single legend should be longer than one page. Nomenclature, abbreviations, symbols, and units used in a figure should match those used in the text. The figure title should be given as the first line of the legend.

LINE DRAWINGS should be labeled on the ordinate and abscissa with the parameter or variable being measured, the units of measure, and the scale. Scales with large or small numbers should be presented as powers of 10. Definitions of symbols should usually appear in the figure legend and not in the figure. Simple symbols (circles, squares, triangles, and diamonds, solid or open) will best survive reduction.

Avoid the use of light lines and screen shading. Instead use black and white hatched and cross-hatched designs for emphasis. Authors who prefer to sumbit their figures electronically may supply images in the following formats: TIFF, GIF, PICT, or PICT2. (After acceptance of a paper, the author will receive a manuscript checklist with more specific information about electronic artwork.).

HALFTONES, such as electron micrographs, should be submitted as high-quality prints or originals (do not send irreplaceable artwork). If possible, use scale bars in place of, or in addition to, magnifications. In GELS, the lanes should be numbered and identified by number in the figure legend.

For COLOR ART please provide a positive slide, if possible, and a print or laser proof. Indicate positioning, lettering, and cropping limits on the print. For composite figures, send the original composite board rather than a print if the quality of the original is much better than that of the print. Do not send irreplaceable work.

LETTERING in Helvetica font is preferable. Use boldface type for axis labels and for the labels A,B,C,... in composite figures; use italic type only as it would be used in the text (for example, for variables and genes). The first letter of each entry should be uppercase; otherwise, use uppercase letters as they would be used in the text (for example, for acronyms). Avoid wide variation in type size within a single figure. In the printed version of the figure, letters should be about 7 point (2 mm) high.

SEQUENCES may be reduced considerably, so make sure the typeface in the original is clear. There should be about 130 characters (including spaces) per line for a sequence occupying the full width of the printed page and about 84 characters per line for a sequence occupying two columns.

REFERENCES AND NOTES are numbered in the order in which they are cited, first through the text and then through the table and figure legends. List a reference only one time. References that are always cited together may be grouped under a single number. Reference to unpublished data should be given a number in the text and placed, in correct sequence, in the references and notes. Use conventional abbreviations for well-known journals; provide complete titles for other journals. Do not use op. cit.

SYMBOLS, ABBREVIATIONS, AND ACRONYMS should be defined the first time they are used.

TABLES should supplement, not duplicate, the text. They should be numbered in the order of their citation in the text. Each table should be generated on a separate page with its legend double-spaced above the table. The first sentence of the legend should be a brief descriptive title. Three horizontal lines are used in tables: at the top and bottom of the table and between the column headings and the table body. Vertical lines are not used between the columns.

Every vertical column should have a heading consisting of a title with the unit of measure in parentheses. Units should not change within a column. Centered headings of the body of the table can be used to break the entries into groups (See the section on lettering for use of italic type and uppercase letters.)

Footnotes should contain information relevant to specific entries or parts of the table.

Units of measure are given in metric. If measurements were made in English units, give metric equivalents.

General Information for Submitting Electronic Figures and Covers

The figures published in SCiENCE are re-lettered to ensure consistent editorial style. Therefore it is very important that the figures you submit are accessible to our staff artists. Our art department is in a Macintosh environment. We use the following s oftware packages: Freehand (version 3.0 or later), Illustrator (version 3.0 or later) and Photoshop (version 2.0 or later). We can also accept figures in these formats (in descending order of preference): TIFF, GIF, PICT or PICT2 and Mac-accessible postsc ript. Providing figures in the above formats will facilitate the timely production of your figures. If you'd like to submit your figures or covers electronically, please read Saving & Naming Files.

Saving & Naming Files

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