ParaGraph: Graph editor support for parallel programming environments

We report here on a graph editor, ParaGraph, that supports massively parallel programming. It provides a flexible mechanism for the concise specification of families of annotated graphs, addressing the problems of user annotation and scale independent graph manipulation. ParaGraph currently serves as the basis for tools supporting communication abstractions in program specification and debugging. Its foundation in an extended form of aggregate rewriting graph grammars makes its adaptation to other parallel programming environments straightforward.The Parallel Programming Environments Project at the University of Massachusetts is supported by the Office of Naval Research under Contract N000014-84-K-0647 and by the National Science Foundation under Grants DCR-8500332 and CCR-8712410.     

Psychologists in state mental hospitals: Problems and recommendations.

Psychology as a discipline has contributed significantly to the development of new treatment methods for severe behavior problems such as those found in the chronically mentally ill. Nevertheless, there are relatively few psychologists practicing in state mental hospitals, and it is difficult to attract and retain young qualified psychologists in these settings. The current article examines some of the more common problems that psychologists face in state facilities, with specific focus on organizational, physician-related, and staff-related issues. Recommendations are provided on ways to cope with problems in these three areas. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Influence of Serum and Hypoxia on Incorporation of [14C]-d-Glucose or [14C]-l-Glutamine into Lipids and Lactate in Murine Glioblastoma Cells

Glucose and glutamine are essential energy metabolites for brain tumor growth and survival under both normoxic and hypoxic conditions. Both metabolites can contribute their carbons to lipid biosynthesis. We used uniformly labeled [¹⁴C]‐U‐d ‐glucose and [¹⁴C]‐U‐l ‐glutamine to examine the profile of de novo lipid biosynthesis in the VM‐M3 murine glioblastoma cells. The major lipids synthesized included phosphatidylcholine (PtdCho), phosphatidylethanolamine (EtnGpl), phosphatidylinositol (PtdIns), phosphatidylserine (PtdSer), sphingomyelin (CerP Cho), bis(monoacylglycero)phosphate (BMP)/phosphatidic acid (PtdOH), cholesterol (C), cardiolipin (Ptd₂Gro), and gangliosides. Endogenous lipid synthesis, using either glucose or glutamine, was greater in media without fetal bovine serum (FBS) than in media containing 10 % FBS under normoxia. De novo lipid synthesis was greater using glucose carbons than glutamine carbons under normoxia. The reverse was observed for most lipids under hypoxia suggesting an attenuation of glucose entering the TCA cycle. Lactate was produced largely from glucose carbons with minimal lactate derived from glutamine under either normoxia or hypoxia. Accumulation of triacylglycerols (TAG), containing mostly saturated and mono‐unsaturated fatty acids, was observed under hypoxia using carbons from either glucose or glutamine. The data show that the incorporation of labeled glucose and glutamine into most synthesized lipids was dependent on the type of growth environment, and that the VM‐M3 glioblastoma cells could acquire lipids, especially cholesterol, from the external environment for growth and proliferation.     

A multiple relay‐based medium access control protocol in multirate wireless ad hoc networks with multiple beam antennas

The advanced technique of multiple beam antennas is recently considered in wireless networks to improve the system throughput by increasing spatial reuse, reducing collisions, and avoiding co‐channel interference. The usage of multiple beam antennas is similar to the concept of Space Division Multiple Access (SDMA), while each beam can be treated as a data channel. Wireless networks can increase the total throughput and decrease the transmission latency if the physical layer of a mobile node can support multirate capability. Multirate wireless networks incurs the anomaly problem, because low data rate hosts may influence the original performance of high data rate hosts. In this work, each node fits out multiple beam antennas with multirate capability, and a node can either simultaneously transmit or receive multiple data on multiple beams. Observe that the transmitting or receiving operation does not happen at the same time. In this paper, we propose a multiple relay‐based medium access control (MAC) protocol to improve the throughput for low data rate hosts. Our MAC protocol exploits multiple relay nodes and helps the source and the destination to create more than one data channel to significantly reduce the transmission latency. Observe that low data rate links with long‐distance transmission latencies are distributed by multiple relay nodes, hence the anomaly problem can be significantly alleviated. In addition, the ACK synchronization problem is solved to avoid the condition that source nodes do not receive ACKs from destination nodes. An adjustment operation is presented to reduce unnecessary relay nodes during the fragment burst period. Finally, simulation results illustrate that our multiple relay‐based MAC protocol can achieve high throughput and low transmission latency. Copyright © 2009 John Wiley & Sons, Ltd.     

含N、K的羧甲基纤维素类吸水剂的制备及性能研究

以过硫酸钾为引发剂,以N,N-亚甲基双丙烯酰胺为交联剂,用羧甲基纤维素与丙烯酸、丙烯酸钠、丙烯酸钾进行自由基接枝共聚,再以氨水中和所得接枝共聚物,制备了不同含氮量的吸水树脂。研究了原料配比及氨水中和度对吸水率的影响。结果表明:在羧甲基纤维素:丙烯酸=1:10,交联剂:引发剂:羧甲基纤维素=1:3:200的条件下,聚合物的吸水性能随体系中丙烯酸中和度的提高而变强;用氨水中和制得的聚合物的吸水性能以中和度为80%时最强,吸去离子水可达563.5g/g、自来水232.5g/g、0.9%的生理盐水100.5g/g、人工尿54.5 g/g,具有相当好的耐盐性和实用性。     

防霉型木地板的工艺特点与防霉剂的选择

概述了防霉型木地板的工艺特点和木质材料用防霉剂的选择原则及防霉作用原理。     

Effect of storage parameters on freeze‐dried kefir grains

The purpose of this study was to use freeze‐drying to preserve microbial activity while extending the shelf life of kefir grains and to determine the best storage temperature. Freeze‐dried kefir grains were lyophilised and were later stored in a multilayer plastic film with a moisture barrier for 90 days at varying temperatures. Microbial activity continued until the 60^th day of storage at 4 °C. PCR analysis was performed to determine Lactobacillus kefiranofaciens as an indicator kefir micro‐organism. It was concluded that the conservation of kefir grains by freeze‐drying protects the natural embedded microbiota; therefore, both the shelf life of kefir grains and the consumption of natural kefir increase.     

Visual enhancement of underwater images using Empirical Mode Decomposition

Most underwater vehicles are nowadays equipped with vision sensors. However, it is very likely that underwater images captured using optic cameras have poor visual quality due to lighting conditions in real-life applications. In such cases it is useful to apply image enhancement methods to increase visual quality of the images as well as enhance interpretability and visibility. In this paper, an Empirical Mode Decomposition (EMD) based underwater image enhancement algorithm is presented for this purpose. In the proposed approach, initially each spectral component of an underwater image is decomposed into Intrinsic Mode Functions (IMFs) using EMD. Then the enhanced image is constructed by combining the IMFs of spectral channels with different weights in order to obtain an enhanced image with increased visual quality. The weight estimation process is carried out automatically using a genetic algorithm that computes the weights of IMFs so as to optimize the sum of the entropy and average gradient of the reconstructed image. It is shown that the proposed approach provides superior results compared to conventional methods such as contrast stretching and histogram equalizing.