Female birds have been shown to have a remarkable degree of control over the sex ratio of the offspring they produce. However, it remains poorly understood how these skews are achieved. Female condition, and consequent variation in circulating hormones, provides a plausible mechanistic link between offspring sex biases and the environmental and social stresses commonly invoked to explain adapti...

Introduction: The present study aimed to investigate the relationship between early maladaptive schemas and sexual self-esteem in female sex workers. Materials and Methods: In this descriptive-correlational study conducted in February 2015, 108 female sex workers residing in Toos women's care center in Mashhad were selected through convenience sampling method. For data collection, Young Early M...

Sex allocation theory for simultaneous hermaphrodites has focused primarily on the effects of sperm competition, but the role of mate choice has so far been neglected. We present a model to study the coevolution of cryptic female choice and sex allocation in simultaneous hermaphrodites. We show that the mechanism of cryptic female choice has a strong effect on the evolutionary outcome: if indiv...

BACKGROUND: The nurse-doctor relationship is historically one of female nurse deference to male physician authority. We investigated the effects of physicians' sex on female nurses' behaviour. METHODS: Nurses at an urban, university based hospital completed one of two forms of a vignette-based survey in January, 2000. Each survey included four clinical scenarios. In form 1 of the questionnaire ...

Simulation models of insects encountering sex pheromone with or without mass trapping in which the searching sex is either male (moths and many insect species) or female (some true bugs, beetles, and flies) were developed. The searching sex moved as a correlated random walk, while the opposite sex remained stationary (calling) and released an attractive sex pheromone. The searching sex was caug...

The female condom is an effective new contraceptive method that can reduce HIV transmission. This study examines use of the female condom after 1 year of its mass marketing and compares this with use of the male condom. It is based on exit interviews conducted among a random sample of male and female customers visiting outlets that sell the female condom. Compared with reported use of the male ...

To investigate whether offspring sex ratio at birth (SRB) was associated with maternal breast cancer risk, the present case-control study and a meta-analysis of literature were done. A total of 389 female breast cancer patients who had at least one offspring participated in the study. From general population 356 healthy female were selected as a control group. Control subjects were frequency ma...