Results 11 to 20 of about 1,243,825 (262)
Widespread sex ratio polymorphism in Caenorhabditis nematodes
Royal Society Open Science, 2023 Although equal sex ratio is ubiquitous and represents an equilibrium in evolutionary theory, biased sex ratios are predicted for certain local conditions. Cases of sex ratio bias have been mostly reported for single species, but little is known about its
Yun Huang +7 more
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European Journal of Human Genetics, 2004 Two recent papers suggest distorted sex and transmission ratios associated with BRCA1 mutations. If real, these would provide novel insights into the normal biological function of this gene and have implications for genetic epidemiologic methods used to estimate penetrance.
Jeffery P, Struewing +4 more
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Economic stress affects the human sex ratio: A retest of the Trivers–Willard hypothesis in Poland
Anthropological Review, 2023 This paper contributes to the verification of the Trivers–Willard hypothesis (TWH). Based on the TWH, observed sex (male-to-female) ratio at birth in a population is presumed to decline when parents experience economic stress.
Artur Mikulec +2 more
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Determinants of child sex ratio in West and South Districts of Tripura, India
Indian Journal of Public Health, 2017 Background: Indian census 2011 has detected declined child sex ratio in the West and South districts of Tripura State. Objectives: To find out the sex ratio at birth and to identify the factors affecting child sex ratio in west and south districts of ...
Himadri Bhattacharjya, Subrata Baidya
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On the optimal sex ratio. [PDF]
Proceedings of the National Academy of Sciences, 1983 The equilibrium structures for various multiallele sex-determining genetic models of panmictic populations with sex expression depending on the genotypes of either the zygote or a parent are described. Even-sex-ratio equilibrium surfaces can exist apart from equilibrium points having coincident male and female allelic frequency sets.
Karlin, Samuel, Lessard, Sabin
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Human sex ratio at amniocentesis and at birth in Taiwan
Taiwanese Journal of Obstetrics & Gynecology, 2012 Objectives: An increase in the proportion of male-to-female live births has raised concerns in Taiwan. Disclosure of fetal sex during prenatal screening is not allowed by the Taiwan government.
I-Wen Lee +3 more
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Climate influences fledgling sex ratio and sex-specific dispersal in a seabird. [PDF]
PLoS ONE, 2013 Climate influences the dynamics of natural populations by direct effects over habitat quality but also modulating the phenotypic responses of organisms' life-history traits. These responses may be different in males and females, particularly in dimorphic
Alvaro Barros +2 more
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Reproduction, 1974 Sex ratios have been the subject of numerous investigations, particularly in studies with humans. In general, however, the literature relating to sex ratio in sheep is limited (Chapman & Lush, 1932; Henning, 1939; Rasmussen, 1940; Karam, 1957). Population studies have generally been based on an expected sex ratio of 0·5, and any ...
K M, Napier, P D, Mullaney
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EVALUATION OF SEMEN SEX RATIO IN COOLED AND FROZEN SEMEN STRAWS BY REAL-TIME PCR [PDF]
Basrah Journal of Veterinary Research, 2016 The study was demonstrated on quantitative evaluation of SRY and ZFX gene of (120) semenstraws from 10 Holliston bull (60) straws in cooling state 5C° and 60 straws after deep freezingin liquid nitrogen) .
Baqer Ja’fer. Hassan +2 more
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Factors Determining Decline in Sex Ratio in Kuwaiti Population [PDF]
المجلة المصرية للسکـان وتنظيم الأسرة, 1985 Census data of kuwait show that the sex ratio among kuwaiti nationals has been declining. This paper examines the influence of varimus factors on sex ratio.
Mostafa El-Shalakani
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