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To define conditions promoting inherited infection by Lyme disease spirochetes in Ixodes ticks, we variously infected ticks with Borrelia afzelii and examined their progenies by dark-field microscopy, immunofluorescence, PCR, and serial passage. No episode of inherited infection was evident, regardless of instar or gender infected or frequency of exposure. We suggest that these spirochetes rarely, if ever, are inherited by vector ticks.  相似文献   
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Behavioral time-sampling was compared with various paper-and-pencil, self-report measures of test anxiety in an examination of the utility of the behavioral measure as an in situo index of test anxiety. The behavioral measure was significantly and positively correlated 0.45 with a paper-and pencil, self-report measure of "facilitative" test anxiety but not with measures of "debilitative" test anxiety (r = -0.15) or general anxiety (r = -0.33) for 12 males and 21 female undergraduates.  相似文献   
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Despite advances in medicine, mortality due to sepsis has not decreased. Pulsed electromagnetic field (PEMF) therapy is emerging as an alternative treatment in many inflammation-related diseases. However, there are few studies on the application of PEMF therapy to sepsis. In the current study, we examined the effect of PEMF therapy on a mouse model of lipopolysaccharide (LPS)-induced septic shock. Mice injected with LPS and treated with PEMF showed higher survival rates compared with the LPS group. The increased survival was correlated with decreased levels of pro-inflammatory cytokine mRNA expression and lower serum nitric oxide levels and nitric oxide synthase 2 mRNA expression in the liver compared with the LPS group. In the PEMF + LPS group, there was less organ damage in the liver, lungs, spleen, and kidneys compared to the LPS group. To identify potential gene targets of PEMF treatment, microarray analysis was performed, and the results showed that 136 genes were up-regulated, and 267 genes were down-regulated in the PEMF + LPS group compared to the LPS group. These results suggest that PEMF treatment can dramatically decrease septic shock through the reduction of pro-inflammatory cytokine gene expression. In a clinical setting, PEMF may provide a beneficial effect for patients with bacteria-induced sepsis and reduce septic shock-induced mortality.  相似文献   
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The task of formulating an efficient system for determining the location of an object, results in the creation of a wide number of applications and services. For this reason, most wireless sensor network applications assume the availability of sensor location information. In this paper, an indoor localization scheme, which is based on synchronized sensor nodes, is proposed. It is efficient in terms of power consumption and location update rate. Furthermore, it resolves the scalability problem usually found in most conventional indoor localization systems in large scale indoor environments. The performance of the proposed scheme is evaluated through experimental implementation and is compared with the Cricket system. The results demonstrate that the proposed scheme is a promising and feasible localization system for a large scale indoor environment.  相似文献   
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The impact of the reverse short-channel effect (RSCE) on device current is stronger in the subthreshold region due to reduced drain-induced barrier lowering (DIBL) and the exponential dependency of current on threshold voltage. This paper describes a device-size optimization method for subthreshold circuits utilizing RSCE to achieve high drive current, low device capacitance, less sensitivity to random dopant fluctuations, better subthreshold swing, and improved energy dissipation. Simulation results using ISCAS benchmark circuits show that the critical path delay, power consumption, and energy consumption can be improved by up to 10.4%, 34.4%, and 41.2%, respectively.  相似文献   
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