Bongaarts and Feeney offer alternatives to period life expectancy with a set of demographic measures equivalent to each other under a Proportionality Assumption. Under this assumption, we show that the measures are given by exponentially weighted moving averages of earlier values of period life expectancy. They are indices of mortality conditions in the recent past. The period life expectancy i...

Mammalian sperm mitochondrial sheath harbors a number of enzymes that are involved in release of energy via oxidative phosphorilation of ATP. The present study was designed to detect the effect of differential sperm mitochondrial activity on the fertility potential and the association of sperm mitochondrial activity index (SMAI) with the sperm motility parameters for cryopreserved semen samples...

Introductions of high yielding inorganic fertilizer are not cheap and leave behind a large amount of dry matter for disposal. Thus there is a need to utilize these plant residues to save fertilizers and maintain a satisfactory level of soil fertility. Hence, with the view of in-situ manuring as well as to recycle the agricultural residue, pot experiments were conducted to study the effect of wh...

The presence of distinct morphological markers in monosomics is important for selection and maintenance of the monosomic plants in subsequent generations and for a well-targeted chromosome substitutions. Here we present cytological and morphological features of the cotton (Gossypium hirsutum L.) monosomic lines developed in Uzbekistan, and their identification by means of translocation tests. W...

We evaluate the use of signature fatty acids and direct hyphal counts as tools to detect and quantify arbuscular mycorrhizal (AM) and saprotrophic fungal (SF) biomass in three Hawaiian soils along a natural soil fertility gradient. Phospholipids16:1u5c and 18:2u6,9c were used as an index of AM and saprotrophic fungal biomass, respectively. Both phospholipid analysis and hyphal length indicated ...

Genetic lesions causing human male infertility are manifold. Besides gross chromosomal aneuploidies and rearrangements, microdeletions and single gene defects can interfere with male fertility. Male fertility is not only dependent on genes controlling the male germ line but also on genes of the networks functional for male gonad development and male somatic development, respectively. It is popu...

Cover crops are essential in agricultural management and especially in organic farming for protecting the soil from erosion, competing with weeds, preventing evaporative losses and improving soil quality and fertility. The choice of cover crop species is crucial in achieving the highest level of weed suppression and soil fertility enhancement. Cover crop systems with rye or mixtures of legumes ...

Composite indices of site moisture and fertility regimes, site variables, and individual tree species were tested for their relationship with site productivity on forest survey plots in the southern Appalachian Mountains. Mew annual basal area increment was significantly associated with the fertility index and site variables including elevation, slope gradient, and stand merchantable size. Four...

Background The obesity pandemic has grown to concerning proportions in recent years, not only in the Western World, but in developing countries as well. The corresponding decrease in male fertility and fecundity may be explained in parallel to obesity. Obesity in men is associated with infertility in numerous studies. MaterialsAndMethods In this review article, electronic searches were undertak...

BACKGROUND Changes in the state of energy balance owing to changes in physical activity may affect the reproductive system. We evaluated the association between physical activity (PA) and fertility and parity in healthy women. METHODS A population-based health survey (HUNT 1) was conducted during 1984-1986 in Nord-Trøndelag county, Norway, with follow-up from 1995 to 1997 (HUNT 2). The study ...