background: in vitro fertilization (ivf) and intra cytoplasmic sperm injection (icsi) are recognized as established and increasingly successful forms of treatment for infertility, yet significant numbers of couples discontinue treatment without achieving a live birth. this study aims to identify major factors that influence the decision to discontinue ivf/icsi treatments. materials and methods:...

Every manufacturer is confronted with the problem of finding the most economical quantity to manufacture in putting through an order. This is a general problem and admits of a general solution, and, however much it may be advisable to exercise judgment in a particular case, such exercise of judgment will be assisted by a knowledge of the general solution. The writer has seen the practical worki...

economists look at the entrepreneurship from the prospective of profitability, investment, risk, and insight supporting the economical development but it seems that, in modern societies, entrepreneurship`s function is beyond the economical bounds. according to the stage and importance of entrepreneurship which is known as the society’s economic and culture evolution engine, it is necessary to d...

A cover of a hypergraph is a collection of edges whose union contains all vertices. Let H = (V, E) be a k-uniform, D-regular hypergraph on n vertices, in which no two vertices are contained in more than o(D/e log D) edges as D tends to infinity. Our results include that if k = o(log D), then there is a cover of (1 + o(1))n/k edges, extending the known result that this holds for fixed k. On the ...