144 research outputs found
Transformacja ładu społecznego w Polsce a problem zdrowotności (na przykładzie Nowej Huty)
Ze wstępu: "Do 1992 roku Polskę, podobnie jak i pozostałe kraje byłej strefy sowieckiej, charakteryzowała
rosnąca umieralność osób dorosłych, a śmiertelność mężczyzn
w Polsce była wyższa niż w którymkolwiek zachodnim kraju europejskim. Mimo
że w latach 90. umieralność osób dorosłych w Polsce się obniżyła, jednak spadek
ten tylko nieznacznie wpłynął na nadal utrzymującą się różnicę względem krajów
EU."(...
Distributed Finite Element Analysis Using a Transputer Network
The principal objective of this research effort was to demonstrate the extraordinarily cost effective acceleration of finite element structural analysis problems using a transputer-based parallel processing network. This objective was accomplished in the form of a commercially viable parallel processing workstation. The workstation is a desktop size, low-maintenance computing unit capable of supercomputer performance yet costs two orders of magnitude less. To achieve the principal research objective, a transputer based structural analysis workstation termed XPFEM was implemented with linear static structural analysis capabilities resembling commercially available NASTRAN. Finite element model files, generated using the on-line preprocessing module or external preprocessing packages, are downloaded to a network of 32 transputers for accelerated solution. The system currently executes at about one third Cray X-MP24 speed but additional acceleration appears likely. For the NASA selected demonstration problem of a Space Shuttle main engine turbine blade model with about 1500 nodes and 4500 independent degrees of freedom, the Cray X-MP24 required 23.9 seconds to obtain a solution while the transputer network, operated from an IBM PC-AT compatible host computer, required 71.7 seconds. Consequently, the 15,000,000 Cray X-MP24 system
An Expert Instructor’s Use of Social Congruence, Cognitive Congruence, and Expertise in an Online Case-Based Instructional Design Course
Promoting and sustaining effective discussion—that which contributes to learning—is a skill that eludes many instructors (Darling-Hammond, 2008; Ge, Yamashiro, & Lee, 2000). This study explored the role and strategies of an expert instructor in an online advanced instructional design (ID) course that utilized a case-based learning (CBL) approach. Discussion posts, as well as interview data, were analyzed and coded to explore how the instructor utilized three strategies noted as being critical to students’ learning during problem-centered discussions: social congruence, cognitive congruence, and content expertise (Schmidt & Moust, 1995; Yew & Yong, 2014). Results showed that facilitation choices were made with course goals in mind: modeling the case analysis process and improving students’ ID problem solving. All three strategies were used frequently during discussion facilitation. Strategies tended to be implemented in clusters, with social congruence strategies appearing in every post but four. Implications are discussed for utilizing a combination of these facilitation strategies, in a dynamic manner, within a case-based context
Ethical issues facing North-South research teams : global population health research; final report
This report shares findings regarding the nature of ethical issues experienced by researchers while conducting Global population health research (GPHR). It aims to reduce instances of discordance between GPHR researchers and agencies that support and oversee such research. In countries where unjust legal rules impinge on research practice, researchers and Ethics Board members especially need to understand the distinction between what is morally required and what is legally required. This is a comprehensive paper which moves towards re-writing research ethics guidelines, providing substantial recommendations, as a beginning
Differential Requirement for LAT and SLP-76 in GPVI versus T Cell Receptor Signaling
Mice deficient in the adaptor Src homology 2 domain-containing leukocyte phosphoprotein of 76 kD (SLP-76) exhibit a bleeding disorder and lack T cells. Linker for activation of T cells (LAT)-deficient mice exhibit a similar T cell phenotype, but show no signs of hemorrhage. Both SLP-76 and LAT are important for optimal platelet activation downstream of the collagen receptor, GPVI. In addition, SLP-76 is involved in signaling mediated by integrin αIIbβ3. Because SLP-76 and LAT function coordinately in T cell signal transduction, yet their roles appear to differ in hemostasis, we investigated in detail the functional consequences of SLP-76 and LAT deficiencies in platelets. Previously we have shown that LAT−/− platelets exhibit defective responses to the GPVI-specific agonist, collagen-related peptide (CRP). Consistent with this, we find that surface expression of P-selectin in response to high concentrations of GPVI ligands is reduced in both LAT- and SLP-76–deficient platelets. However, platelets from LAT−/− mice, but not SLP-76−/− mice, aggregate normally in response to high concentrations of collagen and convulxin. Additionally, unlike SLP-76, LAT is not tyrosine phosphorylated after fibrinogen binding to integrin αIIbβ3, and collagen-stimulated platelets deficient in LAT spread normally on fibrinogen-coated surfaces. Together, these findings indicate that while LAT and SLP-76 are equally required for signaling via the T cell antigen receptor (TCR) and pre-TCR, platelet activation downstream of GPVI and αIIbβ3 shows a much greater dependency on SLP-76 than LAT
Differential Histopathological and Behavioral Outcomes Eight Weeks after Rat Spinal Cord Injury by Contusion, Dislocation, and Distraction Mechanisms
The objective of this study was to compare the long-term histological and behavioral outcomes after spinal cord injury (SCI) induced by one of three distinct biomechanical mechanisms: dislocation, contusion, and distraction. Thirty male Sprague-Dawley rats were randomized to incur a traumatic cervical SCI by one of these three clinically relevant mechanisms. The injured cervical spines were surgically stabilized, and motor function was assessed for the following 8 weeks. The spinal cords were then harvested for histologic analysis. Quantification of white matter sparing using Luxol fast blue staining revealed that dislocation injury caused the greatest overall loss of white matter, both laterally and along the rostrocaudal axis of the injured cord. Distraction caused enlarged extracellular spaces and structural alteration in the white matter but spared the most myelinated axons overall. Contusion caused the most severe loss of myelinated axons in the dorsal white matter. Immunohistochemistry for the neuronal marker NeuN combined with Fluoro Nissl revealed that the dislocation mechanism resulted in the greatest neuronal cell losses in both the ventral and dorsal horns. After the distraction injury mechanism, animals displayed no recovery of grip strength over time, in contrast to the animals subjected to contusion or dislocation injuries. After the dislocation injury mechanism, animals displayed no improvement in the grooming test, in contrast to the animals subjected to contusion or distraction injuries. These data indicate that different SCI mechanisms result in distinct patterns of histopathology and behavioral recovery. Understanding this heterogeneity may be important for the future development of therapeutic interventions that target specific neuropathology after SCI
CpG Island microarray probe sequences derived from a physical library are representative of CpG Islands annotated on the human genome
An effective tool for the global analysis of both DNA methylation status and protein–chromatin interactions is a microarray constructed with sequences containing regulatory elements. One type of array suited for this purpose takes advantage of the strong association between CpG Islands (CGIs) and gene regulatory regions. We have obtained 20 736 clones from a CGI Library and used these to construct CGI arrays. The utility of this library requires proper annotation and assessment of the clones, including CpG content, genomic origin and proximity to neighboring genes. Alignment of clone sequences to the human genome (UCSC hg17) identified 9595 distinct genomic loci; 64% were defined by a single clone while the remaining 36% were represented by multiple, redundant clones. Approximately 68% of the loci were located near a transcription start site. The distribution of these loci covered all 23 chromosomes, with 63% overlapping a bioinformatically identified CGI. The high representation of genomic CGI in this rich collection of clones supports the utilization of microarrays produced with this library for the study of global epigenetic mechanisms and protein–chromatin interactions. A browsable database is available on-line to facilitate exploration of the CGIs in this library and their association with annotated genes or promoter elements
Adolescent Dose and Ratings of an Internet-Based Depression Prevention Program: A Randomized Trial of Primary Care Physician Brief Advice versus a Motivational Interview
Background—Internet-based interventions for education and behavior change have proliferated, but most adolescents may not be sufficiently motivated to engage in Internet-based behavior change interventions. We sought to determine how two different forms of primary care physician engagement, brief advice (BA) versus motivational interview (MI), could enhance participation outcomes in an Internet-based depression prevention intervention.
Methods—Eighty-three adolescents at risk for developing major depression were recruited by screening in primary care and randomized to two groups: BA (1–2 minutes) + Internet program versus MI (10–15 minutes) + Internet program. We compared measures of participation and satisfaction for the two groups for a minimum of 12 months after enrollment.
Results—Both groups engaged the site actively (MI: 90% versus BA: 78%, p=0.12). MI had significantly higher levels of engagement than BA for measures including total time on site (143.7 minutes versus 100.2 minutes, p=0.03), number of sessions (8.16 versus 6.00, p=0.04), longer duration of session activity on Internet site (46.2 days versus 29.34 days, p=0.04), and with more characters typed into exercises (3532 versus 2004, p=0.01). Adolescents in the MI group reported higher trust in their physician (4.18 versus 3.74, p=0.05) and greater satisfaction with the Internet- based component (7.92 versus 6.66, p=0.01).
Conclusions—Primary care engagement, particularly using motivational interviewing, may increase Internet use dose, and some elements enhance and intensify adolescent use of an Internet- based intervention over a one to two month period. Primary care engagement may be a useful method to facilitate adolescent involvement in preventive mental health interventions
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