Svetlov, Pavel Grigorevich

Born on August 28 ( September 9 ), 1892 (according to other sources on August 29 ( September 10 ), 1892 ^[2] ) in the village of Ushaki (now the Tosno District of the Leningrad Region ). His father, Grigory Ivanovich Svetlov, was a Master of Veterinary Sciences, his mother was Maria Petrovna Svetlova (nee Tkachenko) ^[3] .

He studied at the Tsarskoye Selo Imperial Nicholas Gymnasium , from which he graduated in 1910 with a silver medal. Entered the St. Petersburg University in the natural department of the Faculty of Physics and Mathematics, specialized in the Department of Invertebrate Zoology under the guidance of P. P. Ivanov and D. M. Fedotov ^[3] . He worked at the Sevastopol and Murmansk biological stations, studied marine fauna ^[1] . Thesis was devoted to the structure of tideman calfs of sea ​​stars . However, it was not possible to continue scientific research: after graduating from the university in 1915, Pavel Grigorievich was mobilized , graduated from an officer's school and was sent to the Caucasus front of the First World War ^[3] .

After the October Revolution, Svetlov found himself in Perm , where in December 1917 he became an assistant at the department of invertebrate zoology at Perm University , headed by D. M. Fedotov . Soon the first scientific articles on embryology appeared in the press ^[3] . Together with other teachers during the retreat Kolchak was evacuated to the University of Tomsk (1919-1920) ^[4] .

In the autumn of 1925, Pavel Svetlov, at the invitation of Academician N. V. Nasonov, returned to Leningrad , where he conducted a series of experimental works on embryonic regeneration at the Special Zoological Laboratory of the USSR Academy of Sciences ^[1] . Conducted a study of the effects of external factors such as ionizing radiation , poisons , etc., which became the prerequisite for creating a theory of critical periods in the development of mammals . He married Natalya Sergeyevna Svetlova ^[3] .

In 1933, Pavel Svetlov was arrested, but later released and continued to work in the same place. But in March 1935, he and his wife were deported to Kazan for 5 years. Being in exile continued research. March 7, 1938, was arrested on charges of "slandering the Soviet regime and defeatism." During the investigation, he was kept in the Butyrskaya prison , until he was released on May 23, 1940, for lack of evidence of the charge. In 1940–1941 he worked in Tomsk , after which he returned to Leningrad ^[3] .

From 1944 he headed the department of animal genetics and the laboratory of embryology of the biological faculty of the Leningrad University , became a professor . He continued research work ^[1] . In 1945, he became head of the embryology cabinet of the Institute of Obstetrics and Gynecology of the Academy of Medical Sciences of the USSR, which he headed until 1956 ^[3] .

In 1946, Pavel G. was elected a corresponding member of the Academy of Medical Sciences of the USSR ^[1] .

In 1947 he graduated and put into print the book "Fundamentals of mechanics developed", which, however, was published only decades later. After the August 1948 session of VASNIHL , when the persecution of scientific schools related to genetics began , a number of employees of the Faculty of Biology were dismissed, including Pavel Svetlov. The department was closed, the book collection was scattered ^[1] . Like many other scientists, Svetlov had to publicly repent of his imaginary mistakes ^[3] .

Professor V.M. Karasik, professor of the Pediatric Medical Institute , recalled ^[5] in his diary:

“And poor Pavel Grigoryevich, who, having gone to the second conference, uttered so much there that, probably, he himself was sick then and, probably, he didn’t understand what he said there. Yes, what was he to do? Probably, he was not even thinking about himself, but about his wife and daughter ... ”

In the late 1940s, Pavel Grigorievich worked at the All-Union Institute of Experimental Medicine (VIEM) of the Academy of Medical Sciences of the USSR. In the study of embryology at the Institute of Obstetrics and Gynecology, Academy of Medical Sciences of the USSR, together with G. F. Korsakova, he conducted a series of studies on the experimental embryology of mammals ^[3] . At the same time, the name of Svetlov continued to appear in various kinds of denunciations, where he was accused either of Zionism or of morganism ^{[6] [7]} . The principled position of Svetlov and a number of other scientists of the institute in relation to the theory of O. B. Lepeshinskaya led to the closure in 1950 of the department of general morphology and the cessation of many studies on the problems of cytology , histology and embryology ^[8]

At the time of the Khrushchev thaw , the laboratory of IEM embryology was restored, which was headed by Svetlov in 1956, and where he continued experiments to study the influence of environmental environmental factors on the development of embryos ^[1] .

From 1966 to 1974, Svetlov worked as a scientific consultant at the Institute of Cytology, Academy of Medical Sciences of the USSR.

In 1968, Professor P. G. Svetlov, Corresponding Member of the Academy of Medical Sciences of the USSR, together with Professor N. L. Garmasheva and Academician of the Academy of Medical Sciences of the USSR L. S. Persianinov received the State Prize for a series of works on “Antenatal prevention of fetal morbidity and perinatal mortality” ^{[3 ]} .

Svetlov also dealt a lot with issues of popularization and the history of science, issues of scientific education. He wrote articles for the Big Medical Encyclopedia ^[3] . Of interest is his long-term correspondence with a prominent scientist A. A. Lyubishchev ^[9] , published several times ^[2] .

Date of death of the scientist - July 7, 1974 (obituaries in memory of Pavel Grigorievich Svetlov. - Arch. Anat., 1974, v. 67, issue 11, p. 117. 7. In memory of P. G. Svetlov. - Cytology, 1975, t. 17, No. 5, pp. 595-597).

In total, Pavel Svetlov is the author of more than 140 scientific works on comparative, experimental and pathological embryology, problems of regeneration, systematics, ecology, genetics, and the history of science.

The first works of Svetlov appeared were published in the early 1920s; these were articles on the embryology of malleech worms that quickly brought fame to Svetlov ^[3] .

In the second half of the 1920s and early 1930s, Svetlov conducted a series of experimental work on embryonic regeneration . Conducted a study of the effects of external factors such as ionizing radiation , poisons , etc., which became the prerequisite for creating a theory of critical periods in the development of mammals ^[3] .

In 1943-1950, he conducted various experiments to explain the differences in sex sensitivity to starvation and various damaging influences, taking up this topic to study the reasons for the fact that during the siege of Leningrad, male mortality was noticeably higher than that of women. Svetlov found that such differences are found in the properties of the protoplasm of the cells of the male and female bodies ^[3] .

In the second half of the 1950s, Svetlov was engaged in various experiments to study the influence of environmental factors on the development of embryos of laboratory animals. These experiments allowed him to make a number of important generalizations, the most important of which is the theory of critical periods of development, important for both biology and medicine. The theory was based on understanding from the point of view of genetics, cytology, biochemistry and physiology of reactive processes of a variety of information on the problem of reactions of a developing organism accumulated in various experiments ^[10] . One of theoretically substantiated conclusions from this theory on model experiments is the fact that the conditions in which grandmothers were pregnant may influence the appearance and expression of inherited traits in the grandchild's generation ^[3] .

A further continuation of the research and development of the theory was the embryological substantiation of Svetlov's need to protect the early period of the human's womb life (1961), leading to the conclusion that it was necessary to revise the principles of pregnancy protection ^{[3] [1]} .

According to P. G. Svetlov, the development of an organism is a reactive process consisting of a chain of physiological reactions, in each of which the stimulus and the reacting system can be distinguished, and the basic principle of development is dependent development based on the correlative connection between parts of the developing organism ^[11]

The book Physiology (Mechanics) of Development, which did not see the light in 1948, was published after Svetlov’s death, in 1978 ^[11] .

• Belousov L.V. A few words about Pavel Grigorievich Svetlov // Ontogenesis. - 1992. - № 6 . - p . 683-684 .
• Blyakher L. Ya. Pavel Grigorievich Svetlov: On the 80th anniversary of his birth // Ontogenesis. - 1972. - № 5 . - p . 529-530 .
• Zavarzin A.A., Korsakova G.F., Levin V.L., et al. Pavel G. Svetlov // Cytology. - 1972. - № 9 . - p . 1194-1200 .
• Dondua A. K., Zavarzin A. A., Korsakova G. F., et al. In memory of P. G. Svetlova // Tsitologiya. - 1975. - № 5 . - p . 595-597 .
• Pavel G. Svetlov // Arch. anatomy, histology and embryology. - 1972. - № 8 . - pp . 125-127 .
• Schmidt G. A., Knorre A. G. Pavel Grigorievich Svetlov: (To the 70th anniversary of his birth) // Arch. anatomy, histology and embryology. - 1962. - T. 43 , No. 9 . - p . 123-128 .
• Zhinkin L.N. Pavel Grigorievich Svetlov: (On the 70th anniversary of his birth). - Cytology, 1962. - Vol . 4 , No. 4 . - p . 468-470 .