Mutations in daf-2 and age-1 cause a dramatic increase in longevity as well as developmental arrest at the dauer diapause stage in Caenorhabditis elegans. daf-2 and age-1 encode components of an insulin-like signaling pathway. Both daf-2 and age-1 act at a similar point in the genetic epistasis pathway for dauer arrest and longevity and regulate the activity of the daf-16 gene. Mutations in daf...

In every developed country, the economic transition from pre-industrial stagnation to modern growth was accompanied by a demographic transition from high to low fertility. Even though the overall pattern is repeated, there are large cross-country variations in the timing and speed of the demographic transition. What accounts for falling fertility during the transition to growth? To answer this ...

Soil fertility and nutrient-related plant functional traits are in general only moderately related, hindering the progress in trait-based prediction models of vegetation patterns. Although the relationships may have been obscured by suboptimal choices in how soil fertility is expressed, there has never been a systematic investigation into the suitability of fertility measures. This study, there...

1. Understanding how density-dependent and independent processes influence demographic parameters, and hence regulate population size, is fundamental within population ecology. We investigated density dependence in growth rate and fecundity in a recovering population of a semicolonial raptor, the osprey Pandion haliaetus [Linnaeus, 1758], using 31 years of count and demographic data in Corsica....

F atherhood is an important issue to young men surviving cancer as fertility may be impaired by treatment. A number of strategies to preserve fertility are available to adolescent males. Wide variation in practice for adolescent male fertility preservation has previously been shown in North America. No defining data for the UK are available. In the UK, these activities are regulated by the Huma...

Reproductive efficiency is an important aspect of dairy cattle production. To improve it in high yielding dairy cattle, a thorough understanding of the physiology of fertility and the reproductive physiological implications of the increasing metabolic demands associated with increasing production levels is essential. In this respect, the present paper focuses on the neuro-endocrine regulation o...

S-type cytoplasmic male sterility (CMS-S) is the largest group among the three major types of CMS in maize. CMS-S exhibits fertility instability as a partial fertility restoration in a specific nuclear genetic background, which impedes its commercial application in hybrid breeding programs. The fertility instability phenomenon of CMS-S is controlled by several minor quantitative trait locus (QT...

Increased capability for milk production has been associated with a decline in fertility of lactating cows. Nutritional requirements increase rapidly with milk production after calving and result in negative energy balance (NEBAL). NEBAL delays the time of first ovulation through inhibition of LH pulse frequency and low levels of blood glucose, insulin and insulin-like growth factor-I (IGF-I) t...