Propagation model for the Land Mobile Satellite channel in urban environments

This paper presents the major characteristics of a simulation package capable of performing a complete narrow and wideband analysis of the mobile satellite communication channel in urban environments for any given orbital configuration. The wavelength-to-average urban geometrical dimension ratio has required the use of the Geometrical Theory of Diffraction (GTD). For the RF frequency range, the model has been designed to be (1 up to 60 GHz) extended to include effects of non-perfect conductivity and surface roughness. Taking advantage of the inherent capabilities of such a high frequency method, we are able to provide a complete description of the electromagnetic field at the mobile terminal. Using the information made available at the ray-tracer and GTD solver outputs, the Land Mobile Satellite (LMS) urban model can also give a detailed description of the communication channel in terms of power delay profiles, Doppler spectra, channel scattering functions, and so forth. Statistical data, e.g. cumulative distribution functions, level crossing rates or distributions of fades are also provided. The user can access the simulation tool through a Design-CAD user-friendly interface by means of which she can effectively design her own urban layout and run consequently all the envisaged routines. The software is optimized in its execution time so that numerous runs can be achieved in a considerably short time

Modified ultrafiltration improves cerebral metabolic recovery after circulatory arrest

AbstractModified ultrafiltration uses hemofiltration of the patient and bypass circuit after separation from cardiopulmonary bypass to reverse hemodilution and edema. This study investigated the effect of modified ultrafiltration on cerebral metabolic recovery after deep hypothermic circulatory arrest. Twenty-six 1-week-old piglets (2 to 3 kg) were supported by cardiopulmonary bypass (37° C) at 100 ml · kg-1 · min-1 and cooled to 18° C. Animals underwent 90 minutes of circulatory arrest followed by rewarming to 37° C. After being weaned from cardiopulmonary bypass, animals were divided into three groups: controls ( n = 10); modified ultrafiltration for 20 minutes ( n = 9); transfusion of hemoconcentrated blood for 20 minutes ( n = 7). Global cerebral blood flow was measured by xenon 133 clearance methods: stage I--before cardiopulmonary bypass; stage II—5 minutes after cardiopulmonary bypass; and stage III—25 minutes after cardiopulmonary bypass. Cerebral metabolic rate of oxygen consumption, cerebral oxygen delivery, and hematocrit value were calculated for each time point. At point III, the hematocrit value (percent) was elevated above baseline in the ultrafiltration and transfusion groups (44 ± 1.8, 42 ± 1.8 versus 28 ± 1.7, 30 ± 0.7, respectively, p < 0.05). Cerebral oxygen delivery (ml · 100 gm-1 · min-1 ) increased significantly above baseline at point III after ultrafiltration (4.98 ± 0.32 versus 3.85 ± 0.16, p < 0.05) or transfusion (4.59 ± 0.17 versus 3.89 ± 0.06, p < 0.05) and decreased below baseline in the control group (2.77 ± 0.19 versus 3.81 ± 0.16, p < 0.05). Ninety minutes of deep hypothermic circulatory arrest resulted in impaired cerebral metabolic oxygen consumption (ml · 100 gm-1 · min-1 ) at point III in the control group (1.95 ± 0.15 versus 2.47 ± 0.07, p < 0.05) and transfusion group (1.72 ± 0.10 versus 2.39 ± 0.15, p < 0.05). After modified ultrafiltration, however, cerebral metabolic oxygen consumption at point III had increased significantly from baseline (3.12 ± 0.24 versus 2.48 ± 0.13, p < 0.05), indicating that the decrease in cerebral metabolism immediately after deep hypothermic circulatory arrest is reversible and may not represent permanent cerebral injury. Use of modified ultrafiltration after cardiopulmonary bypass may reduce brain injury associated with deep hypothermic circulatory arrest. (J THORAC CARDIOVASC SURG 1995;109:744-52

Semantic Web integration of Cheminformatics resources with the SADI framework

<p>Abstract</p> <p>Background</p> <p>The diversity and the largely independent nature of chemical research efforts over the past half century are, most likely, the major contributors to the current poor state of chemical computational resource and database interoperability. While open software for chemical format interconversion and database entry cross-linking have partially addressed database interoperability, computational resource integration is hindered by the great diversity of software interfaces, languages, access methods, and platforms, among others. This has, in turn, translated into limited reproducibility of computational experiments and the need for application-specific computational workflow construction and semi-automated enactment by human experts, especially where emerging interdisciplinary fields, such as systems chemistry, are pursued. Fortunately, the advent of the Semantic Web, and the very recent introduction of RESTful Semantic Web Services (SWS) may present an opportunity to integrate all of the existing computational and database resources in chemistry into a machine-understandable, unified system that draws on the entirety of the Semantic Web.</p> <p>Results</p> <p>We have created a prototype framework of Semantic Automated Discovery and Integration (SADI) framework SWS that exposes the QSAR descriptor functionality of the Chemistry Development Kit. Since each of these services has formal ontology-defined input and output classes, and each service consumes and produces RDF graphs, clients can automatically reason about the services and available reference information necessary to complete a given overall computational task specified through a simple SPARQL query. We demonstrate this capability by carrying out QSAR analysis backed by a simple formal ontology to determine whether a given molecule is drug-like. Further, we discuss parameter-based control over the execution of SADI SWS. Finally, we demonstrate the value of computational resource envelopment as SADI services through service reuse and ease of integration of computational functionality into formal ontologies.</p> <p>Conclusions</p> <p>The work we present here may trigger a major paradigm shift in the distribution of computational resources in chemistry. We conclude that envelopment of chemical computational resources as SADI SWS facilitates interdisciplinary research by enabling the definition of computational problems in terms of ontologies and formal logical statements instead of cumbersome and application-specific tasks and workflows.</p

Ergatis: a web interface and scalable software system for bioinformatics workflows

Motivation: The growth of sequence data has been accompanied by an increasing need to analyze data on distributed computer clusters. The use of these systems for routine analysis requires scalable and robust software for data management of large datasets. Software is also needed to simplify data management and make large-scale bioinformatics analysis accessible and reproducible to a wide class of target users

Cystatin C: A Candidate Biomarker for Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurologic disease characterized by progressive motor neuron degeneration. Clinical disease management is hindered by both a lengthy diagnostic process and the absence of effective treatments. Reliable panels of diagnostic, surrogate, and prognostic biomarkers are needed to accelerate disease diagnosis and expedite drug development. The cysteine protease inhibitor cystatin C has recently gained interest as a candidate diagnostic biomarker for ALS, but further studies are required to fully characterize its biomarker utility. We used quantitative enzyme-linked immunosorbent assay (ELISA) to assess initial and longitudinal cerebrospinal fluid (CSF) and plasma cystatin C levels in 104 ALS patients and controls. Cystatin C levels in ALS patients were significantly elevated in plasma and reduced in CSF compared to healthy controls, but did not differ significantly from neurologic disease controls. In addition, the direction of longitudinal change in CSF cystatin C levels correlated to the rate of ALS disease progression, and initial CSF cystatin C levels were predictive of patient survival, suggesting that cystatin C may function as a surrogate marker of disease progression and survival. These data verify prior results for reduced cystatin C levels in the CSF of ALS patients, identify increased cystatin C levels in the plasma of ALS patients, and reveal correlations between CSF cystatin C levels to both ALS disease progression and patient survival

DELPHI IX: forecast and analysis of the North American automotive industry. Volume 3: materials

http://deepblue.lib.umich.edu/bitstream/2027.42/1237/2/91191.0001.001.pd

Delphi VIII: forecast and analysis of the North American automotive industry. Volume 3: materials

http://deepblue.lib.umich.edu/bitstream/2027.42/1158/2/88505.0001.001.pd