For 41 chemicals there exist both reasonable data on carcinogenic potency in experimental animals and also a defined Permissible Exposure Level (PEL), which is the upper limit of legally permissible chronic occupational exposure for U.S. workers. These 41 agents are ranked by an index that compares the permitted chronic human exposure to the chronic dose rate that induces tumors in 50% of labor...

Background: This study was performed to evaluate the levels of heavy metals in the livers and kidneys of cattle, sheep and goats from a mining region in the west of Iran. Methods: In this cross-sectional study, 90 samples were collected from the livers and kidneys of cattle (n=30), sheep (n=30) and goats (n=30) from a slaughterhouse in Hamedan City, western Iran. Lead, cadmium, manganese, zi...

Much work in contemporary bioethics defends a broadly liberal view of human reproduction. I shall take this view to comprise (but not to be exhausted by) the following four claims. First, it is permissible both to reproduce and not to reproduce, either by traditional means or by means of assisted reproductive techniques such as IVF and genetic screening. Second, it is permissible either to repr...

It seems that if abortion is permissible, then stem cell research must be as well: it involves the death of a less significant thing (an embryo rather than a fetus) for a greater good (lives saved rather than nine months of physical imposition avoided). However, I argue in this essay that this natural thought is mistaken. In particular, on the assumption that embryos and fetuses have the full m...

The purpose of this study is to investigate the impact of trade credit in the inventory system. It explores an inventory system with noninstantaneous replenishment under conditions of permissible delay in payments. In practice, the supplier allows a certain fixed credit period to settle the account for stimulating retailer’s demand. Besides, the supplier can offer cash discount to encourage ret...

In this paper, a model is developed to determine retailer's inventory policy under two-level trade credit system. It is assumed that the retailer has a powerful position so that he can obtain the full trade credit offered by supplier whereas customer can obtain just the partial trade credit from the retailer. The proposed model also allows fully backlogged shortages. This robust Mathematical mo...

In this paper, two kinds of fuzzy approaches are proposed for not only multiobjective stochastic linear programming problems, but also multiobjective fuzzy random linear programming problems through a probability maximization model. In a probability maximization model, it is necessary for the decision maker to specify permissible values of objective functions in advance, which have a great infl...