introduction lamb production is the largest part of income in sheep industry. therefore, the mortality rate of lambs is a key factor in profit of the sheep breeding. mortality rate of lambs (or lamb mortality rate) in different breeds of sheep under different climatic conditions is varying from 15% to 50% and an average of 9% to 20% has been reported. survival rate is a combination trait that i...

background and aims: air pollution is one of the health problems worldwide. previous epidemiological studies have investigated the impacts of air pollution on respiratory and cardiovascular diseases. the aim of this study was to determine the associations between air pollution levels and different health indicators among world countries. methods: this ecological study was performed in 2013 by u...

Background: The purpose of this study was to evaluate the effect of prophylactic vaginal progesterone in decreasing preterm birth rate and neonatal complications in a high-risk population. Materials and Methods: A randomized, double-blind, placebo- controlled study included 100 high-risk singleton pregnancies( prior preterm birth,short cervix,uterine malformations and large intramural uterine m...

The United States has a high teenage birth rate relative to other developed countries. Children of teenagers experience more difficult childhoods than children born to other mothers, and hence may be more likely to commit crimes subsequently. I assess to what extent international patterns in teen birth rates can explain why the United States had the highest crime rates of developed countries in...

BACKGROUND Socio-economic conditions can affect the secondary sex ratio in humans. Mothers under good environmental conditions are predicted to increase the birth rates of sons according to the Trivers-Willard hypothesis (TWH). This study analyzed the effects of ownership and non-ownership of dwellings on the sex ratio at birth (SRB) on a Ugandan sample. METHODOLOGY/PRINCIPAL FINDINGS Our inv...

Pregnancy and childbearing rates for teenagers remain high in the United States despite well-documented associated adverse health, social, and economic consequences for many of these teenagers and their children. In 1990, approximately 835,000 (10%) teenagers aged 15-19 years became pregnant and either gave birth or had an abortion (CDC, unpublished data, 1995); an estimated 95% of such pregnan...

An increased birth rate occurred in Aberfan during the five years after the disaster there in 1966. It was not confined to the bereaved parents.

This paper is motivated by the following simple question: how does diffusion affect the competition outcomes of two competing species that are identical in all respects other than their strategies on how they spatially distribute their birth rates. This may provide us with insights into how species learn to compete in a relatively stable setting, which in turn may point out species evolution di...