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631.
EI Megargee 《Canadian Metallurgical Quarterly》1977,5(3):289-298
This study investigated the relation of population size, amount of personal space, and population density to the incidence of disruptive behavior over a 3-year period in a correctional institution for male youthful offenders. Population size was significantly correlated with the number but not the rate of disciplinary violations. The total amount of personal space and the index of population density were significantly correlated with both the number and the rate of violations. A post hoc analysis showed that the incidence of uncomfortably hot days had no relation to disruptive behavior. These results are contrasted with laboratory data on human crowding reporting no relation between population density and behavior pathology. It is suggested that the chronic high density explored in the present field study differs from temporarily crowded conditions produced in laboratory research on human crowding. 相似文献
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A. B. Avakyan S. P. Ovchinnikova L. N. Shapiro V. A. Sharapov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1980,14(11):1161-1167
Conclusions During the journal's 50-yr existence, it has shed light on a broad circle of problems associated with water management. As it developed and new problems were put forth by construction practice, the subject matter of papers was expanded, and many questions received a more profound and comprehensive coverage.In the modern stage of the development of our country's water-conservation construction, the journal should, together with traditional problems, focus more attention on questions of territorial flow redistribution, measures for protecting water resources from depletion and pollution, and measures for increasing the effectiveness of both reservoirs and natural water bodies due to their engineering layout; in all cases, the ecological and economic aspects of problems associated with water management should receive broader coverage.Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 11, pp. 36–39, November, 1981. 相似文献
636.
Mars G. Sharapov Ruslan G. Goncharov Svetlana B. Parfenyuk Olga V. Glushkova Vladimir I. Novoselov 《International journal of molecular sciences》2022,23(23)
Peroxiredoxin 6 (Prdx6) is a multifunctional eukaryotic antioxidant enzyme. Mammalian Prdx6 possesses peroxidase activity against a wide range of organic and inorganic hydroperoxides, as well as exhibits phospholipase A2 (aiPLA2) activity, which plays an important role in the reduction of oxidized phospholipids and cell membrane remodeling. Exogenous Prdx6 has recently been shown to be able to penetrate inside the cell. We hypothesized that this entry may be due to the phospholipase activity of Prdx6. Experiments using exogenous Prdx6 in three cell lines (3T3, A549, RAW 264.7) demonstrated that it is the phospholipase activity that promotes its penetration into the cell. Overoxidation of Prdx6 led to a suppression of the peroxidase activity and a 3-to-4-fold growth of aiPLA2, which enhanced the efficiency of its transmembrane transport into the cells by up to 15 times. A mutant form of Prdx6-S32A with an inactivated phospholipase center turned out to be unable to enter the cells in both the reduced and oxidized state of the peroxidase active center. Previously, we have shown that exogenous Prdx6 has a significant radioprotective action. However, the role of phospholipase activity in the radioprotective effects of Prdx6 remained unstudied. Trials with the mutant Prdx6-S32A form, with the use of a total irradiation model in mice, showed a nearly 50% reduction of the radioprotective effect upon aiPLA2 loss. Such a significant decrease in the radioprotective action may be due to the inability of Prdx6-S32A to penetrate animal cells, which prevents its reduction by the natural intracellular reducing agent glutathione S-transferase (πGST) and lowers the efficiency of elimination of peroxides formed from the effect of ionizing radiation. Thus, phospholipase activity may play an important role in the reduction of oxidized Prdx6 and manifestation of its antioxidant properties. 相似文献