Optimizing Supply Decisions in a B2B Exchange Environment

The advent of the Internet is reshaping the landscape of B2B commerce in a significant manner. Emerging e-marketplaces are offering firms an opportunity to optimize their supply chain decisions across a variety of sourcing scenarios. In this paper, we have specifically focused on decision-making for systematic sourcing of make-to-order (MTO) items. We minimize sourcing and purchasing costs in the presence of fixed costs, shared capacity constraints, and volume-based discounts for bundles of items. We consider a private-exchange that facilitates collaborative sourcing and enables a buyer firm to aggregate demand across different units to gain savings from volume-based discounts on individual items or groups of items, avoiding the duplication of tooling investments, and reducing setup costs. Due to the computational complexity of this problem, we develop a heuristic procedure based on Lagrangian relaxation technique to solve the problem. The computational results show that the procedure is effective under a variety of scenarios

Testosterone inhibits the growth of prostate cancer xenografts in nude mice

Abstract Background Traditional beliefs of androgen’s stimulating effects on the growth of prostate cancer (PCa) have been challenged in recent years. Our previous in vitro study indicated that physiological normal levels of androgens inhibited the proliferation of PCa cells. In this in vivo study, the ability of testosterone (T) to inhibit PCa growth was assessed by testing the tumor incidence rate and tumor growth rate of PCa xenografts on nude mice. Methods Different serum testosterone levels were manipulated in male nude/nude athymic mice by orchiectomy or inserting different dosages of T pellets subcutaneously. PCa cells were injected subcutaneously to nude mice and tumor incidence rate and tumor growth rate of PCa xenografts were tested. Results The data demonstrated that low levels of serum T resulted in the highest PCa incidence rate (50%). This PCa incidence rate in mice with low T levels was significantly higher than that in mice treated with higher doses of T (24%, P < 0.01) and mice that underwent orchiectomy (8%, P < 0.001). Mice that had low serum T levels had the shortest tumor volume doubling time (112 h). This doubling time was significantly shorter than that in the high dose 5 mg T arm (158 h, P < 0.001) and in the orchiectomy arm (468 h, P < 0.001). Conclusion These results indicated that low T levels are optimal for PCa cell growth. Castrate T levels, as seen after orchiectomy, are not sufficient to support PCa cell growth. Higher levels of serum T inhibited PCa cell growth

Laparoscopic Nephron-sparing Treatment of Upper Pole Infundibular Obstruction due to Fraley's Syndrome

Fraley's syndrome results from a rare anatomic variant of the renal vasculature leading to compression of the upper pole infundibulum, caliectasis, hematuria, and flank pain. To date there have been few reported cases in which this condition was treated using a minimally invasive approach. Here, we report a case in which a patient with Fraley's syndrome was successfully treated by performing a laparoscopic YV-infundibulo-pyeloplasty with vasculopexy of a posterior segmental renal artery. Minimally invasive collecting system reconstruction without vascular clamping is feasible, potentially less destructive and offers significant advantages in terms of intraoperative visualization and perioperative patient morbidity

Wireless Sensor Networks

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