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Electrospinning porous silica fiber ( Epsf) prepared by electrospinning as the catalyst carrier, took Co and Zn as bimetallic active components. The bimetallic load-type catalyst was prepared by the equal volume impregnation method, and the technical features of SEM, XRF were used to explore the effect of its application on the degradation effect of chemical wastewater. The results showed that when the mass ratio of the Zn and Co bimetal components in the catalyst was 1 1, its synergistic ozone had a good treatment effect on wastewater. The COD degradation rate of wastewater was 97. 1% within 100 min,and after the catalyst was reused 7 times,the COD degradation rate of wastewater could still reach 79. 1%. [ABSTRACT FROM AUTHOR]

Nano-CaCO3 and styrene-butadiene-styrene block copolymer （SBS） were used as additives to prepare nano-CaCO3/SBS composite modified asphalt. The optimum amount of admixture was determined by testing basic physical properties, the performance and micro morphology of asphalt were investigated by rheological property and segregation test, fluorescence microscope observation and thermogravimetric analysis. The results showed that the best proportion of the two admixtures was 5% （mass fraction, the same below） of nano-CaCO3 and 4% of SBS. After adding SBS into nano-CaCO3 modified asphalt, the viscosity of the composite modified asphalt increased at different temperatures, high temperature rutting resistance and low-temperature performance was significantly improved, and storage stability was good. Nano-CaCO3 molecule, SBS molecule and matrix asphalt molecule had good compatibility, and the thermal stability of asphalt was enhanced because of the composite modification.

The current WSN is vulnerable to a variety of malicious attacks, resulting in the decline of its comprehensive performance. Multihop routing involves a number of safety and privacy issues. Problems such as snooping, sinkhole, manipulation, cloning, wormhole, spoofing, and so on affect the integrity, availability, and confidentiality of the WSNs. Therefore, this paper mainly studies the mathematical modeling of WSN multiattack behavior discrimination based on the incidence matrix. The WSN node model is used to collect relevant data and mark and map the disguised data, so as to determine the characteristics of multiattack behavior and establish the WSN multiattack behavior discrimination model based on the incidence matrix. The experimental results show that the designed multiattack behavior discrimination model can distinguish the attack type according to the characteristics, has high recognition ability, can spend a short time to effectively distinguish the attack behavior, has a low false positive rate, and can effectively improve the antiattack ability of the WSN.

The objective of this research is to investigate the expression and function of SKA3 in lung adenocarcinoma.

WCP/steel surface composites were endowed with gradient structure and prepared by powder metallurgy. The mechanical properties, thermal fatigue properties and microstructure of the composites with different W content in the transition layers were analyzed by scanning electron microscopy, metallographic microscope, compression and thermal shock tests, and the influence of W addition on the composites performances was examined. The results show that the composition and structure between the composite layer and the substrate layer are varied by adding tungsten powder in the transition layer, the conflicts in stress, strain, and thermal expansion between the composite layer and the substrate layer are decreased. With the mass fraction of tungsten powder increasing, the W can diffuse both into the substrate layer and the composite layer, which leads to a new phase appearing in the transition layer. The bond between the substrate layer and the composite layer is reinforced. When the W content in the transition layer reaches 30% in mass fraction, the compressive strength reaches 553MPa, and thermal fatigue resistance of WCP/steel surface composite is improved.

The frequency stability of a passive rubidium atomic frequency standard (RAFS) largely depends on the performance of the microwave cavity used in the physics package. In this paper, a large-size slotted tube microwave cavity with an inner diameter of 40 mm, as well as the physics package based on this cavity, were designed and built. Theoretical calculations and experimental results showed that the magnetic lines inside this cavity were highly parallel to the quantization axis. The frequency discrimination slope and the shot noise of the physics package were measured. The results showed that the cavity could be used to realize an RAFS with frequency stability of .

Background: There are numerous potential treatments assessed for acute cerebral ischemia using animal models. This study aimed to assess the effect of these treatments in terms of infarct size and neurobehavioral change. This meta-analysis was conducted to determine if any of these treatments provide a superior benefit so that they might be used on humans. Methods: A systematic search was conducted using several electronic databases for controlled animal studies using only nonsurgical interventions for acute cerebral ischemia. A random-effects model was used. Results: After an extensive literature search, 145 studies were included in the analysis. These studies included 1408 treated animals and 1362 control animals. Treatments that had the most significant effect on neurobehavioral scales included insulin, various antagonists, including N-methyl-Daspartate (NMDA) receptor antagonist ACEA1021, calmodulin antagonist DY-9760e, and α-amino-3-hydroxy-5- methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist YM872, and antiviral agents. Treatments providing the greatest effect on infarct size included statins, sphingosine-1-phosphate agonist (fingolimod), alcohol, angiotensin, and leukotrienes. Treatments offering the greatest reduction in brain water content included various agonists, including sphingosine-1-phosphate agonist fingolimod, statins, and peroxisome proliferator-activated receptor gamma (PPAR-γ). Treatment groups with more than one study all had high heterogeneity (I2 > 80%), however, using meta-regression we determined several sources of heterogeneity including sample size of the treatment and control groups, the occlusion time, but not the year when the study was conducted. Conclusions: Some treatments stand out when compared to others for acute cerebral ischemia in animals. Greater replication of treatment studies is required before any treatments are selected for future human trials.

Abstract Background Postoperative atrial fibrillation (POAF) is the most common complication after coronary artery bypass grafting (CABG). The preventive effect of magnesium on POAF is not well known. This meta-analysis was undertaken to assess the efficacy of intravenous magnesium on the prevention of POAF after CABG. Methods Eligible studies were identified from electronic databases (Medline, Embase, and the Cochrane Library). The primary outcome measure was the incidence of POAF. The meta-analysis was performed with the fixed-effect model or random-effect model according to heterogeneity. Results Seven double-blind, placebo-controlled, randomized clinical trials met the inclusion criteria including 1,028 participants. The pooled results showed that intravenous magnesium reduced the incidence of POAF by 36% (RR 0.64; 95% confidence interval (CI) 0.50-0.83; P = 0.001; with no heterogeneity between trials (heterogeneity P = 0.8, I2 = 0%)). Conclusions This meta-analysis indicates that intravenous magnesium significantly reduces the incidence of POAF after CABG. This finding encourages the use of intravenous magnesium as an alternative to prevent POAF after CABG. But more high quality randomized clinical trials are still need to confirm the safety.

Abstract Background Atrial fibrillation is the most common type of arrhythmia after cardiac surgery. An increasing body of evidence demonstrates that oxidative stress plays a pivotal role in the pathophysiology of atrial fibrillation. N-acetylcysteine (NAC) is a free radical scavenger, and may attenuate this pathophysiologic response and reduce the incidence of postoperative AF (POAF). However, it is unclear whether NAC could effectively prevent POAF. Therefore, this meta-analysis aims to assess the efficacy of NAC supplementation on the prevention of POAF. Methods Medline and Embase were systematically reviewed for studies published up to November 2011, in which NAC was compared with controls for adult patients undergoing cardiac surgery. Outcome measures comprised the incidence of POAF and hospital length of stay (LOS). The meta-analysis was performed with the fixed-effect model or random-effect model according to the heterogeneity. Results Eight randomized trials incorporating 578 patients provided the best evidence and were included in this meta-analysis. NAC supplementation significantly reduced the incidence of POAF (OR 0.62, 95% CI 0.41 to 0.93; P = 0.021) compared with controls, but had no effect on LOS (WMD -0.07, 95% CI -0.42 to 0.28; P = 0.703). Conclusions The prophylactic NAC supplementation may effectively reduce the incidence of POAF. However, the overall quality of current studies is poor and further research should focus on adequately powered randomized controlled trials with POAF incidence as a primary outcome measure.