LP-BM5 virus causes changes in lactic dehydrogenase and oxygen radical production in splenocytes of C57BL/6J mice

The LP-BM5 murine leukemia virus causes acquired immunodeficiency syndrome in C57BL/6J mice (MAIDS), similar to that of AIDS in humans. The objective of this study was to determine the effect of LP-BM5 viral infection on cellular activation and membrane integrity of splenocytes. Oxidative burst in splenocytes in response to exposure to PMA (20 microg/ml) was significantly higher (p<.02) in infected than in control mice at two weeks post-infection using luminol-enhanced chemiluminescence. By 13 weeks post-infection superoxide anion production in infected mice was significantly lower when compared to controls coinciding with decreased proliferative response to mitogens. The extent of cell membrane damage as indicated by lactic dehydrogenase (LDH) activity in serum was significantly higher in infected than in control mice (p<.001). The results from this study suggests that LP-BM5 virus causes an initial stimulation of cellular activity followed by a decreased cell activation characterized by decreased proliferation of splenocytes and decreased oxygen radical production. Decreased cell membrane integrity indicated by increased LDH activity may partly be responsible for these changes.     

GABA and glutamate levels in the substantia nigra reticulata following repetitive cerebral ischemia in gerbils

Repetitive cerebral ischemia produces more severe damage than a similar single duration insult. We have previously shown that, in gerbils, damage in the substantia nigra reticulata (SNr) is seen with repetitive insults rather than a single insult. We have also shown that there is a progressive decrease in the extracellular GABA in the striatum in the days preceding such damage, speculating that a loss of GABA may be in part responsible for this damage. This study evaluates the GABA levels in the SNr in animals exposed to repetitive ischemic insults. Each animal received a total of three ischemic insults of 3-min duration at hourly intervals. In vivo microdialysis was carried out to analyze the GABA and glutamate dialysate levels on Days 1, 3, 5, 7, and 14 following the ischemic insult. In the control and treated (ischemic) animals, there was a significant increase in the GABA levels with the introduction of nipecotic acid on Days 1, 3, 5, and 14. However, on Day 7 there was a significant attenuation in the GABA response to nipecotic acid in the treated animals in comparison to the controls. The glutamate levels in the treated animals were similar to the control animals on Days 1, 3, 5, and 7. However, on Day 14 the glutamate levels were significantly lower than on previous days. Our experiments for the first time measure extracellular glutamate and GABA responses in the SNr in animals exposed to repetitive ischemic insults. Our experiments show that there is a significant decrease in the GABA concentrations at a time when ischemic damage is developing in this region. This confirms our hypothesis that a decrease in GABA may be one factor contributing to neuronal damage during the period following repetitive ischemic insults. Further, the rebound increase in GABA levels on Day 14 with a concomitant fall in glutamate levels would indicate that reparative processes are still active in the 2 weeks following the insult.     

Multi-indicator Active Queue Management Method

A considerable number of applications are running over IP networks. This increased the contention on the network resource, which ultimately results in congestion. Active queue management (AQM) aims to reduce the serious consequences of network congestion in the router buffer and its negative effects on network performance. AQM methods implement different techniques in accordance with congestion indicators, such as queue length and average queue length. The performance of the network is evaluated using delay, loss, and throughput. The gap between congestion indicators and network performance measurements leads to the decline in network performance. In this study, delay and loss predictions are used as congestion indicators in a novel stochastic approach for AQM. The proposed method estimates the congestion in the router buffer and then uses the indicators to calculate the dropping probability, which is responsible for managing the router buffer. The experimental results, based on two sets of experiments, have shown that the proposed method outperformed the existing benchmark algorithms including RED, ERED and BLUE algorithms. For instance, in the first experiment, the proposed method resides in the third-place in terms of delay when compared to the benchmark algorithms. In addition, the proposed method outperformed the benchmark algorithms in terms of packet loss, packet dropping, and packet retransmission. Overall, the proposed method outperformed the benchmark algorithms because it preserves packet loss while maintaining reasonable queuing delay.     

Prevention of deposition and agglomeration of particles in suspensions used for direct absorption of concentrated solar radiation

In direct absorption of solar radiation for industrial purposes, by micron-size graphite particles suspended in nitrogen gas, agglomeration and deposition of these particles are the major problems. This paper discusses two methods for limitation of agglomeration and deposition. The first is to create a thermal repulsion force between the suspension and the surface to keep the particles away. The second is the surface coating of the particles with a very thin silicon-base layer of molecular order.

Theoretical calculations showed that the first method required an impracticably high temperature gradient. The second method reduced the risk of deposition by about five times while negligible change occurred in the size distribution of the particles.     

Home Automation Using Augmented Reality (HAAR)

Wireless Personal Communications - The development of Smart Home Controllers has seen rapid growth in recent years, especially for smart devices, that can utilize the Internet of Things (IoT)....     

A rule‐based approach to detect and prevent inconsistency in the domain‐engineering process

A medium‐sized domain‐engineering process can contain thousands of features that all have constraint dependency rules between them. Therefore, the validation of the content of domain‐engineering process is vital to produce high‐quality software products. However, it is not feasible to do this manually. This paper aims to improve the quality of the software products generated by the domain‐engineering process by ensuring the validity of the results of that process. We propose rules for two operations: inconsistency detection and inconsistency prevention. We introduce first‐order logic (FOL) rules to detect three types of inconsistency and prevent the direct inconsistency in the domain‐engineering process. Developing FOL rules to detect and prevent inconsistency in the domain‐engineering process directly without the need to the configuration process is our main contribution. We performed some experiments to test the scalability and applicability of our approach on domain‐engineered software product lines containing 1000 assets to 20000 assets. The results show that our approach is scalable and could be utilized to improve the domain‐engineering process.     

Dejittering in the transport of MPEG-2 and MPEG-4 video

When multimedia information is transported over a packet-switched network, the quality of presentation can be degraded due to network delay variation or jitter. This paper presents a dejittering scheme that can be used in the transport of MPEG-4 and MPEG-2 video to absorb any introduced network jitter, thus preserving the presentation quality of transported media streams. The dejittering scheme is based on the statistical approximation of delay variation in the arrival times of video packets carrying encoded clock reference values and a filtering and re-stamping mechanism. In addition, a brief overview of the MPEG-4 system is presented.     

Compiler Support for Array Distribution on NUMA Shared Memory Multiprocessors

Management of program data to improve data locality and reduce false sharing is critical for scaling performance on NUMA shared memory multiprocessors. We use HPF-like data decomposition directives to partition and place arrays in data-parallel applications on Hector, a shared-memory NUMA multiprocessor. We describe a compiler system for automating the partitioning and placement of arrays. The compiler exploits Hectors shared memory architecture to efficiently implement distributed arrays. Experimental results from a prototype implementation demonstrate the effectiveness of these techniques. They also demonstrate the magnitude of the performance improvement attainable when our compiler-based data management schemes are used instead of operating system data management policies; performance improves by up to a factor of 5.     

A multilevel computing architecture for embedded multimedia applications

We have designed a new architecture that simplifies integration of heterogeneous IP for multimedia and streaming applications. The multilevel computing architecture (MLCA) is a template architecture featuring multiple processing units. This template architecture for SOC systems uses superscalar techniques to exploit task-level parallelism among different processing units. It supports a natural programming model that relieves programmers from explicitly synchronizing tasks and communicating data. code transformations that improve application performance are easy to incorporate in compilers for this architecture.     

The design and implementation of a modular and extensible Java Virtual Machine

This paper describes the design, implementation, and experimental evaluation of a modular and extensible Java? Virtual Machine (JVM) infrastructure, called Jupiter. The infrastructure is intended to serve as a vehicle for our research on scalable JVM architectures for a cluster of PC workstations, with support for shared memory in software. Jupiter is constructed, using a building block architecture, out of many modules with small, simple interfaces. This flexible structure, similar to UNIX® shells that build complex command pipelines out of discrete programs, allows the rapid prototyping of our research ideas by confining changes in JVM design to a small number of modules. In spite of this flexibility, Jupiter delivers good performance. Experimental evaluation of the current implementation of Jupiter using the SPECjvm98 and the EPCC Java Grande single‐threaded and multithreaded benchmarks reflects competitive performance. Jupiter is on average about 2.5 times faster than Kaffe and about 2 times slower than the Sun Microsystems JDK (interpreter versions only). By providing a flexible JVM infrastructure that delivers competitive performance, we believe we have developed a framework that supports further research into JVM scalability. Copyright © 2003 John Wiley & Sons, Ltd.