Fraunhofer Society

About: Fraunhofer Society is a government organization based out in Munich, Germany. It is known for research contribution in the topics: Laser & Silicon. The organization has 24736 authors who have published 40168 publications receiving 820894 citations.

Evidence for the existence of two forms of membrane tumor necrosis factor: an integral protein and a molecule attached to its receptor.

Abstract: Plasma membranes were isolated from thioglycolate-induced peritoneal mouse macrophages and tested directly in a 51Cr-release assay against WEHI 164 tumor cells. These membranes showed anti-TNF antibody inhibitable killing of the TNF-sensitive tumor cell line, indicating that membrane-associated TNF is present on mouse macrophages. In order to elucidate whether membrane TNF is an integral protein or a molecule attached to a receptor, cells and plasma membranes were treated with low pH buffer. A partial reduction in TNF activity was observed which could be restored by incubation with exogenous TNF. In a Western blot analysis the integral membrane TNF could be identified as the 26-kDa molecule on activated mouse macrophages. These results indicate that both forms of membrane-associated TNF exist on macrophages and are responsible for cell-mediated cytotoxicity against TNF-alpha-sensitive targets.

Carbon-Based Anodes for Lithium Sulfur Full Cells with High Cycle Stability

Abstract: The lithium sulfur battery system has been studied since the late 1970s and has seen renewed interest in recent years. However, even after three decades of intensive research, prolonged cycling can only be achieved when a large excess of electrolyte and lithium is used. Here, for the first time, a balanced and stable lithium sulfur full cell is demonstrated with silicon–carbon as well as all-carbon anodes. More than 1000 cycles, a specific capacity up to 1470 mAh g−1 sulfur (720 mAh g−1 cathode), and a high coulombic efficiency of over 99% even with a low amount of electrolyte are achieved. The alternative anodes do not suffer from electrolyte depletion, which is found to be the main cause of cell failure when using metallic lithium anodes.

Efficient Coupling into Polymer Waveguides by Gratings

Abstract: Investigations of highly efficient grating couplers for polymer slab and strip waveguides fabricated by electron-beam lithography are reported A maximum input efficiency of 67% is achieved The electron-beam direct-writing technique allows one to replicate the original gratings into polymer substrates by embossing An all-polymeric optical chip with efficient grating couplers is demonstrated Waveguide grating couplers with blazed profile and variable grating depth are investigated Thus, the intensity distribution of the outcoupled light is matched to a Gaussian-like profile A focusing blazed grating that couples the light with an efficiency of 42% into a polymer strip waveguide is reported A curvature correction of the grating lines allows one to improve the focusing properties

A multi-stage stochastic supply network design problem with financial decisions and risk management

Abstract: In this paper, a multi-period supply chain network design problem is addressed. Several aspects of practical relevance are considered such as those related with the financial decisions that must be accounted for by a company managing a supply chain. The decisions to be made comprise the location of the facilities, the flow of commodities and the investments to make in alternative activities to those directly related with the supply chain design. Uncertainty is assumed for demand and interest rates, which is described by a set of scenarios. Therefore, for the entire planning horizon, a tree of scenarios is built. A target is set for the return on investment and the risk of falling below it is measured and accounted for. The service level is also measured and included in the objective function. The problem is formulated as a multi-stage stochastic mixed-integer linear programming problem. The goal is to maximize the total financial benefit. An alternative formulation which is based upon the paths in the scenario tree is also proposed. A methodology for measuring the value of the stochastic solution in this problem is discussed. Computational tests using randomly generated data are presented showing that the stochastic approach is worth considering in these types of problems.