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101.
In high complexity electrical systems such as those used in the automotive industries, electric connectors play an important role. The automotive industry is gradually shifting its attention to electric cars, which means more electrical connectors for sensors and data collection. A fault in connectors for sensors used in a vehicle can cause drastic damage to capital equipment and, in the worst case, the loss of life. The studies of faults or degradation of electrical contacts are essential for safety in vehicles and various industries. Although such faults can be due to numerous factors (such as dust, humidity, mechanical vibration, etc.) and some yet to be discovered, high contact resistance is the main factor causing erratic behavior of electrical contacts. This paper presents a study on the computation of electrical contact resistance of two metal conductors (in the form of a disk) with analytical relations and a numerical computation model based on the finite element method (FEM) in COMSOL Multiphysics. The contact spots were considered to have a higher electrical resistivity value (ρcs) than those of the two metal conductors (ρCu). Studies such as the one in view that is carried out on a microscopic level are often difficult to investigate experimentally. Therefore, with the help of a simplified numerical model, the consequences of the degradation of electrical contacts are investigated. To validate the FEM model, the numerical results were compared to those obtained from analytical models. 相似文献
102.
Marius Teodorescu Alexandre Gaspar Greg Spear John L. Skosey Doina Ganea 《Arthritis \u0026amp; Rheumatology》1984,27(10):1122-1129
We have shown previously that serum from patients with rheumatoid arthritis (RA) contains a polyclonal B cell activator that is associated with α2-macroglobulin (α2M). Some biologic effects of this activator appear to be due to a trypsin-like protease attached to α2M. Therefore, in the present study, we used an anti-α2M antibody solid-phase assay, with Chromozym-Try as a substrate, to determine the level of α2M-protease complexes in plasma α2M. We found higher levels of these complexes in RA patients than in 2 control groups. Since α2M-protease complexes have been shown to induce RA-like inflammation in experimental animals and to be produced by lymphoid cells, we speculate that they may be involved in the pathogenesis of RA. However, the role of the other cells or enzyme systems in the formation of these complexes has not yet been ruled out. Results of these investigations could lead to another link between activation of the immune system and joint inflammation. 相似文献
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104.
Anca Maria Cimpean Raluca Ceau?u Marius Raica 《International journal of clinical and experimental pathology》2010,3(2):222-225
Childhood dermal tumors with melanocytic features is an unusual tumor that can create diagnostic confusion. Among them, paraganglioma-like melanocytic tumors- previous included in melanocytic tumors of uncertain malignant potential- has some particular histopathologic and immunohistochemical features. We describe a case of 13 years old girl with a paraganglioma-like dermal melanocytic tumor of the left leg. 相似文献
105.
Sepsis and shock result in disturbances in microcirculatory perfusion and tissue oxygen utilisation that may not be reflected
in global measures of haemodynamics. Near-infrared spectroscopy enables measurement of tissue oxygen saturation (StO2) and provides information on local microvascular and mitochondrial function. This measure could be incorporated with existing
targets of goal-directed therapy to provide an integrated approach to haemodynamic resuscitation of both the macro- and microcirculation
in various shock states. However, key methodological factors must be addressed before widespread clinical application. 相似文献
106.
Marius Karlsen Muhammed Naveed Yousaf Stephane Villoing Are Nylund Espen Rimstad 《Archives of virology》2010,155(8):1281-1293
Salmonid alphavirus (SAV) is the most divergent member of the family Togaviridae and constitutes a threat to farming of salmonid fish in Europe. Here, we report cloning, expression and preliminary functional
analysis of the capsid protein of SAV, confirming it to be expressed as an approximately 31-kDa protein in infected cells.
The protein localizes strictly to the cytoplasm in Chinook salmon embryo cells, and either to the nucleus or cytoplasm in
bluegill fry cells. An expression study of full-length and different truncated versions of the SAV capsid fused to the enhanced
green fluorescent protein demonstrated that the localization is independent of other viral components in both cell lines,
and controlled by the N-terminal 82 aa, which include a conserved, predicted helix and a downstream positively charged region.
Thus, the results suggest that the SAV capsid possesses a cell-type-dependent potential for nuclear import and export. Moreover,
the SAV capsid and its N-terminal 82 aa were shown to be associated with inhibition of cellular proliferation, a hallmark
of the cytopathic effect caused by SAV. These results highlight that the SAV capsid is a multifunctional protein with possible
importance for pathogenesis. 相似文献
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109.
A new preclinical femoral head osteonecrosis model in sheep 总被引:1,自引:0,他引:1
Roberto Vélez Francisco Soldado Alberto Hernández Ignasi Barber Marius Aguirre 《Archives of orthopaedic and trauma surgery》2011,131(1):5-9
Introduction
Animal models have been used as insight into the pathogenesis of osteonecrosis, even though most have failed to reproduce all stages of human disease, limiting progression in experimental treatment modalities. A new surgically induced animal model of femoral head osteonecrosis in sheep is presented. 相似文献110.