A group of 150 American universities and scientific organisations has written to President Donald Trump to protest his executive order on visas and immigration.

The ban prevents people from Iraq, Iran, Syria, Somalia, Sudan, Libya, and Yemen from entering the US for 90 days. People from the seven predominantly Muslim countries holding US visas and green cards have been turned away from flights to the US and detained in US airports.

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The scientific organisations wrote that the ban has "profound implications for diplomatic, humanitarian, and national security interests, in part because of the negative impact on US science and engineering capacity".

The signatories include the largest scientific learned society in the US, the American Association for the Advancement of Science, as well as universities including Harvard, the California Institute of Technology and Trump's alma mater, the University of Pennsylvania.

"Scientific progress depends on openness, transparency, and the free flow of ideas and people, and these principles have helped the United States attract and richly benefit from international scientific talent," the letter reads (see in full below).

"Our nation has a history of embracing refugees and immigrants from across the planet," said Kevin B Marvel, executive officer of the American Astronomical Society, in a statement.

"Closing our borders to people from certain countries and certain ethnic or religious backgrounds recalls some of our darkest days and goes against our national principles."

The AAS stated that the societies also sent copies of the letter to Senate Majority Leader Mitch McConnell, Senate Democratic Leader Charles Schumer, House Speaker Paul Ryan, and House Democratic Leader Nancy Pelosi.

Protesting Trump
People in the UK protesting the US' immigration ban Jack Taylor/Getty Images

Hundreds of scientists have already been affected by the ban, such as Samira Asgari, a medical researcher studying tuberculosis, who had accepted a job at Brigham and Women's Hospital in Boston. She was told by a US consulate at Frankfurt Airport that "it's the US government who issues the visa, and if they change their mind, the visa isn't valid," The Atlantic reported.

"The exchange of ideas, collaboration, networking between scientists of different countries is essential and vital for the advancement of science," Mehrdad Hariri, a Canadian-Iranian and president of the Canadian Science Policy Center, told Vox. "When this is banned or diminished, it has a really drastic effect on scientific research. It's a bad day for science in the US and globally."

John Holdren, former president Barack Obama's science adviser, has called the ban "an abomination", Nature reported.

Protesting Trump
A sign carried at the 21 January women's march against Trump in Austin, Texas. Steve Rainwater / Flickr

The letter in full

Dear President Trump,

The January 27, 2017, White House Executive Order on visas and immigration has profound implications for diplomatic, humanitarian, and national security interests, in part because of the negative impact on US science and engineering capacity.

The undersigned organizations — representing a broad spectrum of professional scientific, engineering and education societies, national associations, and universities — are deeply concerned that this Executive Order will have a negative impact on the ability of scientists and engineers in industry and academia to enter, or leave from and return to, the United States. This will reduce US science and engineering output to the detriment of America and Americans.

Scientific progress depends on openness, transparency, and the free flow of ideas and people, and these principles have helped the United States attract and richly benefit from international scientific talent. From the Apollo program and exploring the far reaches of the universe, to advancing biomedical research for curing diseases and harnessing science to build a thriving high-tech sector, the United States is considered a leader in science, education and innovation. In order to remain the world leader in advancing scientific knowledge and innovations, the US science and technology enterprise must continue to capitalize on the international and multicultural environment within which it operates.

The Executive Order will discourage many of the best and brightest international students, scholars, engineers and scientists from studying and working, attending academic and scientific conferences, or seeking to build new businesses in the United States. Implementation of this policy will compromise the United States' ability to attract international scientific talent and maintain scientific and economic leadership.

Today, we urge the Administration to rescind the Executive Order and we stand ready to assist you in crafting an immigration and visa policy that advances US prosperity and ensures strong borders while staying true to foundational American principles as a nation of immigrants.

Sincerely,

American Association for the Advancement of Science
AACC International
Academy for Eating Disorders
Academy for Radiology & Biomedical Imaging Research
Acoustical Society of America
Academy of Criminal Justice Sciences
American Academy of Forensic Sciences
American Anthropological Association
American Association of Colleges of Pharmacy
American Association for Dental Research
American Association of Geographers
American Association of Immunologists
American Association of Pharmaceutical Scientists
American Association of Physics Teachers
American Association for Public Opinion Research
American Association for the Study of Liver Diseases
American Astronomical Society
American Brain Coalition
American Chemical Society
American College of Neuropsychopharmacology
American Dental Association
American Dental Education Association
American Educational Research Association
American Geophysical Union
American Geosciences Institute
American Institute of Biological Sciences
American Institute of Aeronautics and Astronautics
American Institute of Chemical Engineers
American Institute of Physics
American Mathematical Society
American Meteorological Society
American Ornithological Society
American Physical Society
American Physiological Society
American Phytopathological Society
American Political Science Association
American Psychological Association
American Public Health Association
American Society of Agricultural and Biological Engineers
American Society of Agronomy
American Society of Animal Science
American Society of Association Executives
American Society for Biochemistry and Molecular Biology
American Society of Clinical Psychopharmacology
American Society for Horticultural Science
American Society for Microbiology
American Society of Naturalists
American Society for Pharmacology and Experimental Therapeutics
American Society of Plant Biologists
American Society of Plant Taxonomists
American Society of Tropical Medicine and Hygiene
American Sociological Association
American Statistical Association
Archeological Institute of America
Associated Universities, Inc.
Association for Behavior Analysis International
Association of Research Libraries
Association of American Medical Colleges
Association of American Universities
Association of Independent Research Institutes
Association for Psychological Science
Association for Research in Vision and Ophthalmology
Association of Schools and Colleges of Optometry
Association for the Sciences of Limnology and Oceanography
Association of Southeastern Biologists
Association for Women in Mathematics
Behavior Genetics Association
Biophysical Society
Boston University
Botanical Society of America
Brown University
California Institute of Technology
Cognitive Science Society
Columbia University in the City of New York
Computing Research Association
Consortium for Ocean Leadership
Consortium of Social Science Associations
Controlled Release Society
Council of Graduate Schools
Council on Social Work Education
Crop Science Society of America
Duke University
Earthquake Engineering Research Institute
Ecological Society of America
Entomological Society of America
Federation of Associations in Behavioral and Brain Sciences
Foundation for Science and Disability
Geological Society of America
Genetics Society of America
Harvard University
Human Factors and Ergonomics Society
Institute of Food Technologists
International Association for Dental Research
International Society for Computational Biology
Johns Hopkins University
Law and Society Association
Linguistic Society of America
Materials Research Society
Mathematical Association of America
Michigan State University
Microscopy Society of America
Midwest Political Science Association
National Association of Biology Teachers
National Communication Association
National Organization of Gay & Lesbian Scientists & Technical Professionals (NOGLSTP)
Natural Science Collections Alliance
National Science Teachers Association
Oklahoma Academy of Science
Optical Society of America
Organization for the Study of Sex Differences
Ornithological Council
Paleontological Society
Population Association of America
Princeton University
Research!America
Rutgers, The State University of New Jersey
Seismological Society of America
Society for American Archaeology
Society for Behavioral Neuroendocrinology
Society for Computers in Psychology
Society for Economic Botany
Society of Experimental Social Psychology
Society of General Internal Medicine
Society for Industrial and Applied Mathematics
Society for Mathematical Psychology
Society of Multivariate Experimental Psychology
Society for Neuroscience
Society for Personality and Social Psychology
Society for the Psychological Study of Social Issues
Society for Social Studies of Science
Society for Social Work and Research
Society for the Study of Evolution
Society for the Study of Reproduction
Society of Systematic Biologists
Society of Toxicology
Soil Science Society of America
Stanford University
Stony Brook University
The American Phytopathological Society
The Gerontological Society of America
The Endocrine Society
The Michael J. Fox Foundation
United States Pharmacopeial Convention
University of California System
University of Cincinnati
University of Iowa
University of Pennsylvania
Vanderbilt University
Vision Sciences Society
Washington University in St. Louis
Yale University

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