STEM

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  DOAJ (Directory of Open Access Journals)

  Internet Archive Scholar  Tutorial

ArXiv.org (Cornell University Library)
Offers open access to research papers in physics, mathematics, computer science, quantitative biology, quantitative finance, statistics, electrical engineering and systems science, and economics. Coverage goes back to 1991.

National Academies Press
Provides full-text ebooks in several fields of science and science policy, published by the National Academies of Sciences, Engineering, and Medicine.

OSTI.GOV (U.S. Department of Energy Office of Scientific and Technical Information)
Presents over 70 years of research results from DOE and its predecessor agencies. Research results include journal articles/accepted manuscripts and related metadata; technical reports; scientific research datasets and collections; scientific software; patents; conference and workshop papers; books and theses; and multimedia. Some research is not currently available to the general public. Look for “This content will become publicly available on” in the left column.

bioRxiv (Cold Spring Harbor Laboratory)
Offers free access to unpublished preprints in the life sciences. Pronounced "bio-archive." Articles are not peer-reviewed and edited before being posted online. An article may be posted prior to, or concurrently with, submission to a journal but should not be posted if it has already been published.

BioMed Central
Search for articles in freely accessible biology and biomedical journals.

PubMed  Tutorial
Offers indexing of journal articles and books in all areas of biomedicine. Worldwide coverage with an emphasis on English-language peer-reviewed journals. Maintained by the U.S. National Library of Medicine. This index is free to search, but only some of the articles listed are freely available to non-subscribers.

PubMed Central
Free digital archive of biomedical and life sciences journal literature from the National Institutes of Health. This database provides a subset of the content listed in PubMed (above), but every article in PubMed Central is freely available.

Virginia Henderson Global Nursing e-Repository
Contains journal articles, research reports, datasets, dissertations, conference papers, and learning objects covering all areas of nursing. Works included are both published and unpublished. Open access; provided by the Honor Society of Nursing, Sigma Theta Tau International.

MedlinePlus
MedlinePlus brings together authoritative information from NLM, the National Institutes of Health (NIH), and other government agencies and health-related organizations. Provides articles on various diseases, symptoms, drugs and procedures, as well as interactive health tutorials, research news, local resources, directories of hospitals and physicians, clinical trials and links to PubMed for journal citations.

National Center for Health Statistics
Web portal for U.S. public health statistics and surveys.