All-Polish Youth demonstrated against Jewish medical students operating on Christian cadavers. The medical faculties caved in, and Jewish students were supplied with Jewish cadavers. Polish radicals then demanded segregation of Jewish students, first asking for "voluntary" segregation and when this was refused attacking Jewish students. Following violent demonstrations by Polish radicals, in 1937-8 most Polish universities introduced segregation. By 1939, most Polish institutes of higher learning implemented a numerus clausus system. USSR Certain scientific and educational institutions in the USSR, such as the MSU Faculty of Mechanics and Mathematics implemented anti-Jewish restrictions in the second half of the XX century under the guise of numerus clausus. Officially claimed to help promote enrollment of applicants belonging to ethnic minorities underrepresented in Soviet science, such as Yakuts, this policy was effectively used to discriminate Jewish applicants . According to Edward Frenkel , this led to a creation of a strong mathematical community in the advanced mathematics department of Gubkin Russian State University of Oil and Gas, which as a consequence was to a significant degree comprised of Jewish students denied entry to the Moscow State University. North America Between 1918 and the 1950s a number of private universities and medical schools in the United States introduced numerus clausus policies limiting admissions of students based on their religion or race to certain percentages within the college population. Many minority groups were negatively impacted by these policies; one of the groups affected was Jewish applicants, whose admission to some New England- and New York City-area liberal arts colleges fell significantly between the late 1910s and the mid-1930s. For instance, the admission to Harvard University during that period fell from 27.6% to 17.1% and in Columbia University from 32.7% to 14.6%. Corresponding quotas were introduced in the medical and dental schools resulting during the 1930s in the decline of Jewish students: e.g. in Cornell University School of Medicine from 40% in 1918–22 to 3.57% in 1940–41, in Boston University Medical School from 48.4% in 1929–30 to 12.5% in 1934–35. At Yale University, Dean Milton Winternitz's instructions to the admissions office regarding ethnic quotas were very specific: "Never admit more than five Jews, take only two Italian Catholics, and take no blacks at all." During this period, a notable exception among U. S. medical schools was the medical school of Middlesex University, which had no quotas and many Jewish faculty members and students; school officials believed