We examine the colour structure and charged particle yield for both the tt̄ signal and the irreducible background processes contributing to e+e− → bb̄W+W− production close to the tt̄ threshold. The charged particle multiplicity for the various components of the cross section is computed as a function of several kinematic variables. Our study may have important implications for recently proposed st...

three grass species, agropyron desertorum (agde) and agropyron elongatum (agel) and recently, bromus tomentellus (brto) are mainly used for range improvement as mixed seeding in semi-arid areas of iran. because there is little information about management of these grasses, this study was conducted at the sisab research station in northern iran to evaluate their responses to grazing management a...

abstract lowland rice (oryza sativa l.) in south asia is under stress, as nitrogen removals by crops are higher than their replenishment through fertilizers. limited information is available on optimizing nitrogen dose in lowland rice to turn out higher yield. the present investigation aimed to optimize nitrogen fertilization and it’s response to the growth and yield of lowland rice. we evaluat...

The aim of the paper is to address the issue of operational improvements in manufacturing firms, especially when yield losses result in a significant increase of the production cost. In a multistage production environment the firm must decide which production stage(s) should receive more “attention” in order to minimize the overall cost incurred from yield losses. Yield variability is a factor ...

a model of the iranian wheat market is specified and fitted to data from 1981-2008. severaldiagnostic tests were employed in the analysis to determine the specification of the model. despitethe simplicity of the model and data problems, an examination of the econometric model leads toseveral conclusions with possible important policy implications for the wheat economy in iran.the general result...

stem reserve remobilization is very important to keep the grain yield in wheat under terminal drought but the importance of this mechanism is unclear under terminal salinity. in this research stem reserve remobilization under terminal salinity were studied in greenhouse on four genotypes no14 and no49, different in remobilization, and bam as salt-tolerant and ghods as salt-sensitive cultivars. ...

drought stress is a major factor limiting crop production. investigation of physiological characteristics related to drought tolerance and crop production may be useful in selecting drought tolerant cultivars as well as in improving crop yield. two drought tolerant (azar2 & back cross roshan) and two drought susceptible (marvdast & shiraz) cultivars were investigated in both greenhouse and fiel...

Fruit waste extract was selected as the sole substrate for carotenoid production and the effect of parameters like pH, temperature and agitation have been studied. A two-step simple sequential strategy was employed for the optimization of carotenoid production by Rhodotorula rubra. In the first step, one factor at a time was employed to evaluate the impact of pH on carotenoid production. Th...

Estimation of genetic trends is necessary to monitor and evaluate selection programs. The objective of this study was to estimate the genetic trends for milk yield in Iranian Holsteins cows using random regression test day model. Data set was consisted of 743205 test-day records from 1991 to 2008, which were collected by the Animal Breeding Centre of Iran. Breeding, environmental and phenotypic...