SUMMARY. Daisy is a Soil-Plant-Atmosphere system model designed to simulate water balance, heat balance, solute balance and crop production in agro-ecosystems subjected to various management strategies. The water balance model comprises a surface water balance and a soil water balance. The surface water includes a model for snow accumulation and melting, a model for interception, through-fall, ...

In both ecology and fish-cultivation, a knowledge of the efficiency with which food is converted into growth is of considerable importance. Conversion to growth, however, is but one aspect of the balance of nutrients in general, and it is therefore appropriate to consider the whole of this balance, and to do so with particular reference to selected constituents of living matter, the turnover an...

The answers to many agronomic questions can only be obtained from long-term experiments in which the evolution of responses to experimental treatments can be observed for several years. In this paper, we describe our experience in designing and running an experiment set up to study changes in the nitrogen balance associated with a continual rotation of summer and winter crops grown on a Tokomar...

four west african dwarf (wad) grower bucks averaging 6 kg in weight and aged between 5-6 months of age were used in a digestive trial to determine the intake and digestibility of raw or processed pigeon pea seed meal based diets. the diets designated rpbd, spbd, tpbd and bpbd were formulated from cassava peel, palm kernel cake, brewers dry grain, bone meal and common salt to contain 15% of raw,...

To explore whether nitrogen retention can differ on an isonitrogenous diet by changing when protein is consumed, we performed a short-term study in older individuals (64.5 ± 2.0 years) performing daily exercise while in energy balance. Participants consumed an isonitrogenous-isocaloric diet with the timing of a protein or carbohydrate beverage after exercise (protein after exercise [PRO], carbo...

OBJECTIVE To compare methods for assessing changes in body composition during gonadal hormone replacement therapy in a group of HIV-positive men with AIDS wasting syndrome. DESIGN The study included a 21-day, double-blind, randomized, placebo-controlled inpatient intervention and a 12-week open-label intervention. The inpatient intervention included 18 men who were confined to a metabolic war...

To evaluate the nitrogen pollution load in an aquifer, a water and nitrogen balance analysis was conducted over a thirty-five year period at five yearly intervals. First, we established a two-horizon model comprising a channel/soil horizon, and an aquifer horizon, with exchange of water between the aquifer and river. The nitrogen balance was estimated from the product of nitrogen concentration ...

BACKGROUND The protein equivalent of nitrogen appearance is an indirect index commonly used to assess dietary protein intake in patients on CAPD. Moreover it has been suggested that the ratio between nitrogen appearance and dietary nitrogen intake (fractional urea synthesis) can predict nitrogen balance in uraemic patients. Several formulae to directly calculate the protein equivalent of nitrog...

Postoperative nitrogen balance was monitored in twelve patients undergoing hysterectomy under either epidural analgesia or general anaesthesia. The mean cumulative five-day nitrogen losses were significantly lower after epidural analgesia than after general anaesthesia. Nitrogen sparing presumably results from inhibiting the stress-induced release of catabolic hormones, since epidural analgesia...

Nitrogen balance in agroecosystems provides a quantitative framework of N inputs and outputs and retention in the soil that examines the sustainability of agricultural productivity and soil and environmental quality. Nitrogen inputs include N additions from manures and fertilizers, atmospheric depositions including wet and dry depositions, irrigation water, and biological N fixation. Nitrogen o...