The sex ratio of white births was consistently higher than that for nonwhite births--a finding which is consistent with earlier studies. Part of the racial differences can perhaps be explained by differences in socioeconomic environment. For the moment, the differential white-nonwhite sex ratio ...
After institutional review board approval, a questionnaire was uploaded on SurveyMonkey and sent to anesthesia providers through their program coordinators in United States (US) to complete the survey. The current US national total-population sex ratio is 0.97 male (s)/female with an at-birth sex...
Background: The expected ratio of male to female births is generally believed to be 1.05, also described as the male proportion of 0.515. Objectives: We describe trends in sex ratio at birth and in fetal deaths in the United States, in African Americans and in whites, and in Japan, two ...
In , dams that conceive in their postpartum oestrus and then lose their firstborn litter bias the sex ratio of the litter toward females in utero. The present study identifies the source of litter sex ratio bias in these postpartum pregnant non-lactating dams. The female bias arises first th...
关键词: Annual increment Clonal growth Microsatellites Populus euphratica Oliv. Resource allocation Sex ratio DOI: 10.1007/s00468-012-0828-y 被引量: 32 年份: 2013 收藏 引用 批量引用 报错 分享 全部来源 求助全文 Springer 参考文献 引证文献
In the United States a low urban sex ratio has been attributed to industrialization and the consequent demand for female labor in urban centers. Japanese cities, however, have not attracted a disproportionately female population in spite of heavy industrialization. On the other hand, Philippine cities...
Sex ratio theory predicts that, if prevailing ecological or social circumstances differentially influence the fitness benefits of offspring of each sex, pa... R. G. NAGER, P. MONAGHAN,R Griffiths,D. C. HOUSTON - 《Proceedings of the National Academy of Sciences of the United States of America...
Neither sex-ratio nor gender differences in depression were found, similar to the pattern found among university students. No demographic variable was correlated significantly with depression. The present findings are considered in terms of methodological differences between studies. It is concluded that ...
The impact of T-ACASI was more pronounced (odds ratio = 2.5) for residents of locales that have historically been less tolerant of same-gender sexual behaviors and for respondents in households with children (odds ratio = 3.0). 展开
This resource allocation then leads to split sex ratios depending on the amount of resources available to a bumblebee colony: colonies under low resource conditions will show a male–biased investment ratio, whereas colonies under high resource conditions allocate more resources towards females. However...