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Effects of semen sexing kits (HeiferplusTM and BullplusTM) supplemented to frozen-thawed bull semen on pregnancy rates,foetal sex ratios and selected reproductive parameters in cows
Heiferplus Bullplus foetal sex pregnancy rate cow
2015/7/28
It has been claimed that artificial insemination (AI) of cows with frozen-thawed semen treated with commercially produced kits, HeiferplusTM (HP, in favour of female gender) and BullplusTM (BP, in fav...
Sex ratios at sexual maturity and longevity: Evidence from Swedish register data
longevity mortality sex ratios
2014/11/25
Background: This study tests the recently proposed hypothesis that the contextual sex ratio at sexual maturity is related to longevity. Previous empirical research in the United States has shown that ...
Sex ratios at sexual maturity and longevity: Evidence from Swedish register data
longevity mortality sex ratios
2014/11/25
Background: This study tests the recently proposed hypothesis that the contextual sex ratio at sexual maturity is related to longevity. Previous empirical research in the United States has shown that ...
Could changes in reported sex ratios at birth during China's 1958-1961 famine support the adaptive sex ratio adjustment hypothesis?
China famine sex ratio at birth
2014/11/25
Background: The adaptive sex ratio adjustment hypothesis suggests that when mothers are in poor conditions the sex ratio of their offspring will be biased towards females. Major famines provide opport...
Does predation control adult sex ratios and longevities in marine pelagic copepods?
predation contro adult sex ratios longevities marine pelagic copepods
2014/4/16
We assess the causes of adult sex ratio skew in marine pelagic copepods by examining changes in these ratios between the juveniles and adults, sexual differences in juvenile stage durations, and morta...
Masculine sex ratios, population age structure and the potential spread of HIV in China
AIDS/HIV China migration modelling sex ratios sexual behavior
2010/1/29
There is much speculation regarding the contribution of China’s changing demography to the spread of HIV/AIDS. We employ a bio-behavioral macrosimulation model of the heterosexual spread of HIV/AIDS t...
Sex ratios at birth in populations of Eastern and Southern Africa
Sex ratios birth Southern Africa
2009/9/14
Sex ratios at birth in populations of Eastern and Southern Africa.
THE COMPETITIVE SAVING MOTIVE: EVIDENCE FROM RISING SEX RATIOS AND SAVINGS RATES IN CHINA
THE COMPETITIVE SAVING MOTIVE EVIDENCE FROM RISING SEX RATIOS SAVINGS RATES IN CHINA
2014/3/12
While the high savings rate in China has global impact, existing explanations are incomplete. This paper proposes a competitive saving motive as a new explanation: as the country experiences a rising ...
Working Late: Do Workplace Sex Ratios Affect Partnership Formation and Dissolution?
Working Late Workplace Sex Ratios Partnership Formation
2016/3/7
In this paper, I analyze the association between workplace sex ratios and partnership formation and dissolution. I find that the risk of dissolution increases with the fraction of coworkers of the opp...
How Do Sex Ratios Affect Marriage and Labor Markets? Evidence from America's Second Generation
Household and family models immigration family structure
2013/10/18
Sex ratios, i.e., relative numbers of men and women, can affect marriage prospects, labor force participation, and other social and economic variables. But the observed association between sex ratios ...