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In this article, we consider the optimal topology design and distributed formation control problem of multiagent systems (MAS) with complex-weighted directed topology. First, a framework is proposed to associate optimal topology of MAS to a constrained optimization problem with a complex Laplacian matrix, which is independent of the agent dynamics. The main contribution of the proposed approach compared with existing results is that the proposed approach does not require the calculation of the stabilizing matrix such that the closed-loop system is asymptotically stable, and a unique set of complex weights that satisfy associated cooperative conditions can be chosen. Then, a distributed formation control protocol is proposed to enable all agents to achieve the control goal. Finally, some numerical example results are provided to demonstrate the effectiveness of the proposed scheme.  相似文献   
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The neuropeptide substance P (SP) triggers a variety of tumor-promoting signaling pathways through the activation of neurokinin-1receptor (NK1R), a class of neurokinin G protein-coupled receptors superfamily. Recent researches in our and other laboratories have shown the overexpression of both SP and NK1R in breast cancer (BC) patients. SP/NK1R signaling is strongly implicated in the pathogenesis of BC through affecting cell proliferation, migration, metastasis, angiogenesis, and resistance. Therefore, SP/NK1R signaling responses must be rigorously regulated; otherwise, they would contribute to a more aggressive BC phenotype. Recently, microRNAs (miRNAs) as a specific class of epigenetic regulators have been shown to regulate NK1R and thus, controlling SP/NK1R signaling responses in BC. This review summarizes the current knowledge of the role of SP/NK1R signaling and its therapeutic potentials in BC. We also provide an overview regarding the effects of miRNA-mediated NK1R regulatory mechanisms in controlling BC tumorigenesis to gain a clearer view and thus better management of cancer.  相似文献   
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The effect of concurrent administration of antibiotics on the detection of methicillin-resistant Staphylococcus aureus (MRSA) remains unresolved. Here, we assessed the concordance of paired nasal swabs processed using commercial PCR and culture and found high concordance in both the absence and presence of antibiotics with activity against MRSA (93.7% [95% confidence interval [CI], 88.1%, 96.8%] and 90.9% [95% CI, 84.8%, 94.7%], respectively), although PCR was more likely to be positive in the presence of antibiotics. (This study has been registered at ClinicalTrials.gov under registration no. NCT01234831.)  相似文献   
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Background: Obesity is a multifactorial disorder due to the complex interaction between genetic and environmental factors. Liver X receptor alpha (LXRα), encoded by the gene NR1H3, is involved in lipoprotein metabolism and its genetic variations may also play a role in the aetiology of obesity.

Aim: To assess the association of two NR1H3 polymorphisms (rs11039155 and rs2279238) and their haplotypes with obesity in an Iranian population.

Subjects and methods: A total of 447 unrelated subjects (including 206 overweight, 162 obese and 79 controls) were enrolled in the study and were genotyped by TaqMan assay using DNA from peripheral blood. The association of these two LXRα polymorphisms with the presence of obesity and overweight was assessed.

Results: There was no significant association between the two SNPs and obesity, even after adjustment for age and sex. By logistic regression using a dominant model, the odds ratios for obesity were: 1.32 (0.85–2.74) for rs11039155 and 0.77 (0.30--1.99) for rs2279238. Haplotype analyses identified three common haplotypes GC, GT and AC with frequency greater than 1%, but none of the haplotypes was associated with the risk of obesity.

Conclusions: This study revealed that there was no significant association between LXRα polymorphisms and the presence of obesity in an Iranian population and suggests that these two SNPs are not major contributors to obesity risk in this population.  相似文献   

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Journal of Neurology - Hereditary neuropathy with liability to pressure palsies (HNPP) is characterized by recurrent sensory and motor neuropathy in individual nerves starting in adolescence or...  相似文献   
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