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841.
Spandan Pathak Prateek Verma Sumit K. Ram Supratim Sengupta 《Proceedings. Biological sciences / The Royal Society》2020,287(1941)
Societies rely on individual contributions to sustain public goods that benefit the entire community. Several mechanisms, that specify how individuals change their decisions based on past experiences, have been proposed to explain how altruists are not outcompeted by selfish counterparts. A key aspect of such strategy updates involves a comparison of an individual''s latest payoff with that of a random neighbour. In reality, both the economic and social milieu often shapes cooperative behaviour. We propose a new decision heuristic, where the propensity of an individual to cooperate depends on the local strategy environment in which she is embedded as well as her wealth relative to that of her neighbours. Our decision-making model allows cooperation to be sustained and also explains the results of recent experiments on social dilemmas in dynamic networks. Final cooperation levels depend only on the extent to which the strategy environment influences altruistic behaviour but are largely unaffected by network restructuring. However, the extent of wealth inequality in the community is affected by a subtle interplay between the environmental influence on a person''s decision to contribute and the likelihood of reshaping social ties, with wealth-inequality levels rising with increasing likelihood of network restructuring in some situations. 相似文献
842.
Presence of retrovirus in the B95-8 Epstein-Barr virus-producing cell line from different sources 总被引:1,自引:0,他引:1
Joseph J. Tumilowicz Gary E. Gallick James L. East Sen Pathak John J. Trentin Ralph B. Arlinghaus 《In vitro cellular & developmental biology. Plant》1984,20(6):486-492
Summary The B95-8 cell line, a widely used source of highly transforming Epstein-Barr virus (EBV), obtained from the laboratory of
origin, harbored an infectious retrovirus. This retrovirus generally resembled the Type D retroviruses structurally and developmentally
and like the Type D retroviruses preferred Mg2+ to Mn2+ in its RNA-directed DNA polymerase reaction. Evidence for the presence of retrovirus was found in B95-8 cultures from two
other sources within the United States, either by assay for polymerase or by electron microscopy. Comparison of two B95-8
cell lines showed cytogenetic differences as well as differences in retroviral activities. The results suggest that any B95-8
culture should be tested for the presence of retrovirus before its use as a source of EBV.
This research was supported through the National Research and Demonstration Center (HL-17269-07) awarded to Baylor College
of Medicine by the National Heart, Lung, and Blood Institute, Bethesda, MD, by RD-125 from the American Cancer Society, by
K06 CA14219, CA16781, CA25465, and CA16672 from the National Cancer Institute, Bethesda, MD, and by G-429 from the Robert
A. Welch Foundation. G. E. G. was supported by Public Health Service training Grant CA-09299. 相似文献
843.
Crude metabolites of 21 of 60 fungal cultures isolated from some of the common cereals collected from different parts of India were found to be toxic. Of these toxin-producing fungi, 79% caused hepatic pathology of varying severity in mice. Serum glutamate pyruvate transaminase values and blood urea nitrogen were found to be high in such experimental animals. 相似文献
844.
Dubey Sarvesh Kumar Kumar Anil Pandey Amritanshu Pathak Amit Srivastava S. K. 《Plasmonics (Norwell, Mass.)》2022,17(3):1279-1291
Plasmonics - In this work, we theoretically study the plasmonic behavior of Ag and Au with a hyperbolic metamaterial (HMM) and propose a numerical simulation of a D-shaped surface plasmon resonance... 相似文献
845.
846.
Haiyan Wang Yongyong Yan Janak L. Pathak Wei Hong Jing Zeng Dongyang Qian Binwei Hao Haiqing Li Jinlan Gu Richard T. Jaspers Gang Wu Ming Shao Gongyong Peng Haifeng Lan 《Journal of cellular and molecular medicine》2023,27(4):515-528
Due to the lack of effective treatments, osteoarthritis (OA) remains a challenge for clinicians. Quercetin, a bioflavonoid, has shown potent anti-inflammatory effects. However, its effect on preventing OA progression and the underlying mechanisms are still unclear. In this study, Sprague–Dawley male rats were divided into five groups: control group, OA group (monosodium iodoacetate intra-articular injection), and three quercetin-treated groups. Quercetin-treated groups were treated with intragastric quercetin once a day for 28 days. Gross observation and histopathological analysis showed cartilage degradation and matrix loss in the OA group. High-dose quercetin-group joints showed failure in OA progression. High-dose quercetin inhibited the OA-induced expression of MMP-3, MMP-13, ADAMTS4, and ADAMTS5 and promoted the OA-reduced expression of aggrecan and collagen II. Levels of most inflammatory cytokines and growth factors tested in synovial fluid and serum were upregulated in the OA group and these increases were reversed by high-dose quercetin. Similarly, subchondral trabecular bone was degraded in the OA group and this effect was reversed in the high-dose quercetin group. Our findings indicate that quercetin has a protective effect against OA development and progression possibly via maintaining the inflammatory cascade homeostasis. Therefore, quercetin could be a potential therapeutic agent to prevent OA progression in risk groups. 相似文献
847.
848.
The distribution of constitutive heterochromatin and nucleolus organizer regions (NOR's) in somatic as well as in meiotic chromosomes of Bos taurus, Bos banteng, Bison bison, and their hybrids are analyzed. C-bands are present in the centromeric regions of every autosome. The X chromosome does not show a distinct C-band in the centromeric region, whereas the Y chromosome contains an appreciable amount of C-band material. In somatic metaphases, NOR's are present on the telomeric ends of five pairs of autosomes. During pachytene, five autosomal bivalents contain NOR's on their terminal ends. Meiotic preparations made from sterile bulls did not contain stages beyond the degenerating pachytene, which are C-banding, more frequently showed clustering of heterochromatin than did the pachytene stage in normal bulls. 相似文献
849.
The chromosomes of the Asian mice, Mus fulvidiventris (booduga?), are typical of the Mus in general, viz., 40 telocentric chromosomes. The centromeric heterochromatin does not fluoresce brightly. The G band pattern of the euchromatin is the same as that of M. musculus. The diploid number of M. dunni is also 40, but each autosome possesses a short, heterochromatic second arm. The X chromosome is a long submetacentric, whose entire short arm and the terminal segment of the long arm are heterochromatic. The Y is a long telocentric and is heterochromatic. The G band pattern of the long arms of M. dunni involved only the addition of C bands. Mus dunni and M. booduga are sympatric in many localities in India, but they can be separated by karyological and subtle morphological differences. 相似文献
850.
Conservatism in the arrangement of genetic material in rodents 总被引:6,自引:0,他引:6