Study on the Actuating Performance of an Embedded Macro Fiber Composite Considering the Shear Lag Effect

Macro fiber composite (MFC), which are new ultrathin piezoelectric smart materials, are mostly applied in the fields of shell structure deformation and vibration control. Among others, the application of embedded MFCs in sandwich structures has received wide attention. Currently, its actuating force formula is primarily acquired based on the Bernoulli–Euler Model, which does not consider the shear lag effect and actuating force of MFC ends. To study the actuating performance of an MFC in a sandwich structure, according to its action characteristics, the MFC is divided into upper and lower actuating units without any interaction between to two under the condition of plane strain, and the shear lag effect is considered between the units and the top and bottom of the sandwich structure. The actuating force of the MFC ends is obtained by considering its influence on the bending deformation of the sandwich structure, which deduces the actuating force formula of the embedded MFC. In contrast to ANSYS piezoelectric simulation, the distribution of the MFC interior normal stress is similar to the result from ANSYS piezoelectric simulation, and there is a very small deviation between the MFC end and central normal stress and the result from ANSYS piezoelectric simulation. Taking the end deflection of the sandwich structure with an embedded MFC as an example, the actuating force simulation of the MFC considering the shear lag effect is compared with the ANSYS piezoelectric simulation and actuating force simulation based on the Bernoulli–Euler model. The result indicates that the actuating force simulation of the MFC considering the shear lag effect is closer to the ANSYS piezoelectric simulation, which proves the rationality and necessity of considering the shear lag effect and end actuating force of the MFC.     

Effect of Carbon Nanofibers on Physical,Adhesion and Rheological Properties of Liquid Epoxidized Natural Rubber Modified Asphalt

This study aimed to evaluate the effects of carbon nanofibers (CNFs) on the performance of liquid epoxidized natural rubber (LENR)-modified asphalt. The physical, adhesion and rheological properties were determined by several tests such as penetration, elastic recovery, ring and ball softening point, Brookfield rotational viscometer, AFM and dynamic shear rheometer. LENR was used at concentrations of 3, 6, and 9%, while CNFs were used at contents of 0.3, 0.4, and 0.5% by weight of asphalt. Conventional test results showed that the increases in LENR and LENR/CNFs composite contents in binder leads to an increase in the hardness and consistency and a reduction in the temperature susceptibility of base asphalt. Adhesion results revealed that the addition of CNFs significantly increases the adhesion and bonding properties of base and rubberized binders. Rheological properties analysis exhibited that LENR improved the viscoelastic properties and permanent deformation resistance of asphalt at different temperatures and frequencies. On the other hand, it was found that the addition of CNFs significantly improves the stiffness, elasticity, and hardness of LENR-modified binders. The 6% LENR and 0.4% CNFs were found to be the optimum to enhance the physical, adhesion, and rheological properties of asphalt in this study. Thus, it can be stated that the addition of CNFs is promising to improve the performance of rubberized binders for high temperature applications.     

Restirring and Reheating Effects on Microstructural Evolution of Al–Zn–Mg–Cu Alloy during Underwater Friction Stir Additive Manufacturing

Friction stir additive manufacturing (FSAM) can be potentially used for fabricating high-performance components owing to its advantages of solid-state processing. However, the inhomogeneous microstructures and mechanical properties of the build attributed to the complex process involving restirring and reheating deserve attention. This study is based on the previous research of the underwater FSAMed 7A04 aluminum alloy and adopts a quasi in situ experimental method, i.e., after each pass of the underwater FSAM, samples were taken from the build for microstructural observation to investigate the restirring and reheating effects on microstructural evolution during the underwater FSAM. Fine-grain microstructures were formed in the stir zone during the single-pass underwater FSAM. After restirring, the grain size at the bottom of the overlapping region decreased from 1.97 to 0.87 μm, the recrystallization degree reduced from 74.0% to 29.8%, and the initial random texture transformed into a strong shear texture composed of the C {110}<11¯0>. After reheating, static recrystallization occurred in the regions close to the new additive zones, increasing the grain size and recrystallization degree. This study not only revealed the microstructural evolution during the underwater FSAM but also provided a guideline for further optimization of the mechanical properties of the Al–Zn–Mg–Cu alloy build.     

右美托咪定联合舒芬太尼用于术后镇痛对宫颈癌根治术患者心血管稳定性及VAS评分的影响

目的 观察右美托咪定联合舒芬太尼用于术后镇痛对宫颈癌根治术患者心血管稳定性及VAS评分的影响.方法 选取于2014年8月至2016年1月来济南军区总医院行宫颈癌根治术的宫颈癌患者64例,按照随机数表法将所有患者分为观察组和对照组,每组各32例.两组患者术后镇痛均使用舒芬太尼,其中观察组患者术后镇痛时加用右美托咪定.在术后1h、术后6h、术后12h、术后1d、术后2d时采用视觉模拟评分法(VAS)法对患者的疼痛程度进行对比分析,比较两组患者在各时间点心血管稳定性.结果 术后1h、术后6h、术后12h、术后1d、术后2d时,观察组患者收缩压、舒张压、心率和呼吸频率均低于对照组.术后观察组患者术后1h、术后6h、术后12h、术后1d、术后2d各时间点舒张压明显低于对照组,差异有统计学意义(t值分别为4.86、4.48、6.75、4.70、5.46,均P<0.01).术后观察组患者术后1h、术后6h、术后12h、术后1d、术后2d各时间点呼吸频率明显低于对照组,差异有统计学意义(t值分别为8.39、9.28、10.81、12.24、10.75,均P<0.01).自术后6h起,术后12h、术后1d和术后2d时观察组患者收缩压明显低于对照组,差异有统计学意义(t值分别为3.40、3.94、5.07、2.94,均P<0.05).术后1h时,对照组患者与观察组患者VAS评分比较差异无统计学意义(t=0.10,P>0.05).术后6h、术后12h、术后1d、术后2d时对照组患者VAS评分明显高于观察组患者(t值分别为4.89、3.35、3.08、4.21,均P<0.01).结论 右美托咪定联合舒芬太尼用于宫颈癌根治术后患者镇痛比单用舒芬太尼镇痛的患者心血管稳定性和VAS评分更高.     

Circulating coxsackievirus A16 identified as recombinant type A human enterovirus, China

To determine the relationship of coxsackievirus A16 (CA16) to prototype CA16-G10, we conducted a phylogenetic analysis of circulating CA16 strains in China. Complex recombinant forms of CA16-related viruses involving multiple human enteroviruses, subgroup A (CA4, CA16, and enterovirus 71), are prevalent among patients with hand, foot, and mouth disease.     

珠江三角洲新生儿转运网络10年工作及效果报告

目的 报告和评价珠江三角洲新生儿转运网络１０年工作及其效果。方法 介绍新生儿转运网络方法和分析有关效果的资料。结果 转运网络现有８７家医院;１０年共转运急,危重症新生儿８１２４例,转运途中病死率为０．４３％;第三级ＮＩＣＵ收容８０８９例,病死率为２．０７％。结论该ＮＴＮ所实行的运转机制合理适用,促进了网络单位包括三级ＮＩＣＵ的进步提高,是降低新生儿死亡率的重要措施。     

苏州地区城乡生活饮用水水质调查与分析

目的掌握苏州地区城镇与农村生活饮用水水质卫生状况及水质指标自然本底值,为建立健全城乡生活饮用水质监测网络提供依据。方法按现行《生活饮用水标准检验方法》（GB／T5750．2）中《水样的采集与保存》,于2010年丰水期在沿长江和环太湖等典型地区采集城镇和农村集中式供水单位的出厂水水样,按《生活饮用水标准检验方法》（GB／T5750—2006）进行水质全项目检测分析。结果2010年丰水期苏州地区城乡饮用水主要不合格指标为铝和三氯乙醛,主要理化常规指标铅、氟化物、硝酸盐、三氯甲烷、铝、氯化物、硫酸盐、溶解性总固体、总硬度、耗氧量等本底值,分别为0．0014、0．62、1．21、0．0046、0．17、48．6、70．0、288．3、118．1、1．44mg／L。结论苏州沿长江和环太湖等典型地区城乡饮用水水质指标基本符合《生活饮用水卫生标准》（GB5749—2006）水质要求,能够保障城乡居民饮水安全及社会发展需求。     

浅议职业病危害评价中的选址与总体布局

目的 针对选址与总体布局,阐述相关注意事项,探讨检查表法在职业病危害评价工作中的应用模式.方法 通过查阅相关文献,同时结合工作实践及经验进行探讨.结果 该方法能够满足职业病评价中选址与总体布局方面的评价要求.结论 检查表法在选址、总体布局等一些具有共性的评价单元中能获得较好的应用效果.     

上海世博会园区内伤害流行病学特征分析

[目的]了解中国2010年上海世博会（简称“上海世博会”）园区内伤害流行病学特征。[方法]利用“中国2010年上海世界博览会园区内就诊异常情况监测和报告系统”（后称“就诊监测报告系统”）,观察上海世博会园区内伤害病例,对其伤害原因、伤害性质等流行病学特征进行调查分析。[结果]从2010年5月1日至10月31日,伤害监测系统共收集12505例伤害病例。5月份游客伤害发生率最高（月均3．01／万）,在世博局采取健康宣教以及改善园区内设施等一系列干预措施后,游客伤害发生率逐步下降,从5月初的4．50／万降低到最后一周的0．80／万。伤害分别是≥65岁和0～14岁游客的第1和第3位就诊原因。游客的主要伤害原因是跌倒和坠落。但是园区内最主要的伤害性质是挫伤和擦伤。[结论]上海世博会园区内伤害发生特征表明,在大型活动中,及时进行健康干预能有效地降低伤害的发生。     

Vitamin Supplementation Protects against Nanomaterial-Induced Oxidative Stress and Inflammation Damages: A Meta-Analysis of In Vitro and In Vivo Studies

The extensive applications of nanomaterials have increased their toxicities to human health. As a commonly recommended health care product, vitamins have been reported to exert protective roles against nanomaterial-induced oxidative stress and inflammatory responses. However, there have been some controversial conclusions in regards to this field of research. This meta-analysis aimed to comprehensively evaluate the roles and mechanisms of vitamins for cells and animals exposed to nanomaterials. Nineteen studies (seven in vitro, eleven in vivo and one in both) were enrolled by searching PubMed, EMBASE, and Cochrane Library databases. STATA 15.0 software analysis showed vitamin E treatment could significantly decrease the levels of oxidants [reactive oxygen species (ROS), total oxidant status (TOS), malondialdehyde (MDA)], increase anti-oxidant glutathione peroxidase (GPx), suppress inflammatory mediators (tumor necrosis factor-α, interleukin-6, C-reactive protein, IgE), improve cytotoxicity (manifested by an increase in cell viability and a decrease in pro-apoptotic caspase-3 activity), and genotoxicity (represented by a reduction in the tail length). These results were less changed after subgroup analyses. Pooled analysis of in vitro studies indicated vitamin C increased cell viability and decreased ROS levels, but its anti-oxidant potential was not observed in the meta-analysis of in vivo studies. Vitamin A could decrease MDA, TOS and increase GPx, but its effects on these indicators were weaker than vitamin E. Also, the combination of vitamin A with vitamin E did not provide greater anti-oxidant effects than vitamin E alone. In summary, we suggest vitamin E alone supplementation may be a cost-effective option to prevent nanomaterial-induced injuries.