background: sediments are inseparable fractions of wetland ecosystems that work as a his-torical archive in the process of recording heavy metal aggregation changes. this study was carried out for assessing co, ni, and zn in sediment samples of mighan wetland using geo-accumulation index in 2013. methods:the sediment samples were taken from 11 stations. the samples were subjected to bulk digest...

the purpose of this study was the introduction of seed accumulation index as a new approach in the evaluation of soil seed bank consistency in the populus caspica in noor reserved forest park. sampling were made above ground vegetation at peak vegetation cover during june 2010 by systematic- selective method. soil samples were collected during late june, late november and early february by hamm...

abstract- olive (olea europaea l.) is one of the most valuable and widespread fruit trees in iran. salt stress-induced changes in membrane stability, photosynthesis and antioxidant enzyme activity were examined on four olive cultivars (dakal, shiraz, zard and amigdalifolia) by emphasizing the correlation between measured parameters and ion (k+, na+) accumulation. plants were subjected to four s...

providing healthy food and protecting sources from pollution has been one of the concerns of human societies and decision – making centers so that protecting food from pollution, detecting sources of pollution and measuring them become important. because of nutritive and political significance of grape in this area, extensive use of leaf and fruit of this plant, developing urban areas around gr...

this research was done in hydroponic environment in greenhouse at 3 stages (vegetative, flowering and full product) in 5 concentrations of cd (0.1, 0.3, 0.9, 2.7, and 10 mm) for investigating physiological and biological effects. this study revealed that the increase of cd concentration in understudy treatments causes the 49% reduction of sugar solution in 10 mm treatment. on the other hand, th...

Several descriptions of basically one transformation technique, viz. accumulation, are compared. Their basis, viz. the associativity and the existence of a neutral element inherent in a monoid, is identiied.

Two dysgenic models of declining general intelligence have been proposed. The first posits that since the Industrial Revolution those with low g have had a reproductive advantage over those with high g. The secondposits that relaxed purifying selection against deleteriousmutations inmodernpopulations has led to g declining due to mutation accumulation. Here, a meta-analytic estimate of the decl...

We study the spectrum of a periodic self-adjoint operator on the axis perturbed by a small localized nonself-adjoint operator. It is shown that the continuous spectrum is independent of the perturbation, the residual spectrum is empty, and the point spectrum has no finite accumulation points. We address the existence of the embedded eigenvalues. We establish the necessary and sufficient conditi...

We studied the importance of selection and constraint in determining the limits of adaptive radiation and the consequences of adaptive radiation in an experimental system. We propagated four replicate lines of the bacterium Pseudomonas fluorescens derived from a single ancestral clone in 95 environments, where growth was limited by the availability of a single carbon source for 1,000 generation...

We propose a model in which economic relations and institutions in advanced and less developed economies di er as these societies have access to di erent amounts of information. This lack of information makes it hard to give the right incentives to managers and entrepreneurs. We argue that di erences in the amount of information arise because of the di erences in the scale of activities in rich...