limitations of water and nitrogen in soil usually restrict plant growth. the objective of this study was to evaluate the effects of different amounts of supplemental irrigation at different growth stages and application of different rates of nitrogen fertilizer on grain yield and water productivity of wheat cultivars. a field experiment was conducted in the agricultural research station of shah...

Wages and Productivity Growth in a Dynamic Monopoly* This Paper studies the intertemporal problem of a monopolistic firm that engages in productivity-enhancing innovations to reduce its labour costs. If the level of wages is sufficiently low, the firm’s rate of productivity growth approaches the rate of wage growth and eventually the firm reaches a steady state where its unit labour cost remain...

Productivity It is within the framework of productivity that bryophytes are often considered unimportant as components of the ecosystem. As Martin and Adamson (2001) have pointed out, the photosynthetic capacity of mosses is generally considered to be much lower than that of the tracheophytes. However, they contend that this may be a misleading conclusion based on the method of calculating rate...

This theoretical study reports on the impact of perceived indoor air quality for productivity loss in air-conditioned office buildings. A new derivation of productivity calculation model based on pollution loads and contaminant removal effectiveness is applied and the effect of the improved ventilation efficiency on productivity is estimated. The findings show that the proportion dissatisfied i...

Mild hypothermia condition in mammalian cell culture technology has been one of the main focuses of research for the development of breeding strategies to maximize productivity of these production systems. Despite the large number of studies that show positive effects of mild hypothermia on specific productivity of r-proteins, no experimental approach has addressed the indirect effect of lower ...

BACKGROUND AND OBJECTIVES: Bioenergy is a phenomenon that has attracted humans’ attention for about a century. The desirable biological properties of chlorella sp.microalgae have turned it to one of the most ideal options for the production of biodiesel. However, the economic issues must be taken into account in its industrial scale production. The present study aims t...

The dynamic properties of the optimal growth model are examined, based on a one good and two factor-labor and capital--model with a labor-surplus economy due to a fixed wage rate. If the average capital productivity is higher than the time discount rate which is assumed to be larger than the population growth rate, then the economy reaches the full employment stationary state in a finite amount...

The productivity of enzyme fermentations depends critically on maintaining a high oxygen transfer rate to satisfy the optimal oxygen demand of the microorganism for product formation. Among the several factors that affect oxygen transfer rates in a fermentor are the air flow rate and agitation. The production of a-amylase by Bacillus amyloliquefaciens was performed in 600-mL and 5-litre ferment...

Labour market imperfections are one of the leading causes of economic backwardness that result in under utilization of labour, the most important input in production process. Labour markets are shallow in subsistence agricultural economies which causes problem in determining the wage rate. The household production function provides an alternative to estimating the shadow wage rate such that it ...