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991.
In this paper, to monitor the border in real-time with high efficiency and accuracy, we applied the compressed sensing (CS) technology on the border monitoring wireless sensor network (WSN) system and proposed a reconstruction method based on approximately l0 norm and fast gradient descent (AL0FGD) for CS. In the frontend of the system, the measurement matrix was used to sense the border information in a compressed manner, and then the proposed reconstruction method was applied to recover the border information at the monitoring terminal. To evaluate the performance of the proposed method, the helicopter sound signal was used as an example in the experimental simulation, and three other typical reconstruction algorithms 1)split Bregman algorithm, 2)iterative shrinkage algorithm, and 3)smoothed approximate l0 norm (SL0), were employed for comparison. The experimental results showed that the proposed method has a better performance in recovering the helicopter sound signal in most cases, which could be used as a basis for further study of the border monitoring WSN system.  相似文献   
992.

Background

Hypertension is one of the leading causes of disease burden across the world. In China, the latest nationwide survey of prevalence of hypertension was ten year ago, and data in rural areas is little known. More information about hypertension prevalence could help to improve overall antihypertensive health care. We aimed to estimate the pooled prevalence of hypertension in rural areas of China.

Methods

Comprehensive electronic searches of PubMed, Web of Knowledge, Chinese Web of Knowledge, Wangfang, Weipu and SinoMed databases were conducted to identify any study in each database published from January 1, 2004 to December 31, 2013, reporting the prevalence of hypertension in Chinese rural areas. Prevalence estimates were stratified by age, area, sex, publication year, and sample size. All statistical calculations were made using the Stata Version 11.0 (College Station, Texas) and Statsdirect Version 2.7.9.

Results

We identified 124 studies with a total population of 3,735,534 in the present meta-analysis. Among people aged 18 years old in Chinese rural areas, the summarized prevalence is 22.81% (19.41%–26.41%). Subgroup analysis shows the following results: for male 24.46% (21.19%–27.89%, for female 22.17% (18.25%–26.35%). For 2004–2006: 18.94% (14.41%–23.94%), for 2007–2009, 21.24% (15.98%–27.01%) for 2010–2013: 26.68%, (20.79%–33.02%). For Northern region 25.76% (22.36%–29.32%), for Southern region 19.30%, (15.48%–24.08%).

Conclusions

The last decade witnessed the growth in prevalence of hypertension in rural areas of China compared with the fourth national investigation, which has climbed the same level as the urban area. Guidelines for screening and treatment of hypertension in rural areas need to be given enough attention.  相似文献   
993.
The reactions between Laccase (extracted from China lacquer of Rhus vernicifera) and various substrates (3,4-Dihydroxybenzaldehyde, Guaiacol, Pyrogallol, Gallic acid) have been studied using LKB-2107 batch microcalorimetry system. Based on calorimetry, a new method has been proposed. Laccase activity and the Michaelis constant K(m) have been determined simultaneously by this method. The method is simple, sample-saving, and valid for a wider range of substrate concentrations. Furthermore, it can be extended for assaying other enzymes catalyzing reactions using this method.  相似文献   
994.
995.
996.
Lu  Chenyang  Sun  Tingting  Li  Yanyan  Zhang  Dijun  Zhou  Jun  Su  Xiurong 《Applied microbiology and biotechnology》2018,102(1):355-366
Applied Microbiology and Biotechnology - Low-dose (LD, 100 mg kg−1 day−1), moderate-dose (MD, 200 mg kg−1 day−1), and...  相似文献   
997.
998.
A series of indolylcyclohexylamines possessing potent and selective serotonin reuptake inhibition is reported. The most interesting compounds proved to have subnanomolar 5-HT transporter activity, and exhibited moderate 5-HT(1A) affinity.  相似文献   
999.
In an earlier study, we showed that estradiol (E2) inhibits proliferation and transformation in cultured rat hepatic stellate cells (HSCs) and that the actions of E2 are mediated through estrogen receptors (ERs). This study reports on an investigation of the cellular localization of ER subtypes ERalpha and ERbeta using immunohistochemistry in experimental fibrotic liver rats and of each ER subtype expression in cultured rat HSCs by evaluating the produced mRNA and protein. The results indicate that high levels of ERbeta expression and low or no levels of ERalpha expression were observed in normal and fibrotic livers and in quiescent and activated HSCs from both males and females. The specificity of E2-mediated antiapoptotic induction through the ERbeta was shown by dose-dependent inhibition by the pure ER antagonist ICI 182,780 in HSCs which were undergoing early apoptosis. These findings demonstrate for the first time that rat HSCs possess functional Erbeta, but not Eralpha, to respond directly to E2 exposure.  相似文献   
1000.
Gao Z  Li Z  Zhang Y  Huang H  Li M  Zhou L  Tang Y  Yao B  Zhang W 《Biotechnology letters》2012,34(3):507-514
The glucose oxidase (GOD) gene from Penicillium notatum was expressed in Pichia pastoris. The 1,815 bp gene, god-w, encodes 604 amino acids. Recombinant GOD-w had optimal activity at 35–40°C and pH 6.2 and was stable, from pH 3 to 7 maintaining >75% maximum activity after incubation at 50°C for 1 h. GOD-w worked as well as commercial GODs to improve bread making. To achieve high-level expression of recombinant GOD in P. pastoris, 272 nucleotides involving 228 residues were mutated, consistent with the codon bias of P. pastoris. The optimized recombinant GOD-m yielded 615 U ml−1 (2.5 g protein l−1) in a 3 l fermentor—410% higher than GOD-w (148 U ml−1), and thus is a low-cost alternative for the bread baking industry.  相似文献   
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