Influence of electroacupuncture with acupoints selected along meridians on gene expression of angiotensinogen of myocardial ischemia rats

Objective:To observe the effects of electroacupuncture along meridians on the expression of angiotensinogen(AGT)mRNA in myocardial tissue of myocardial ischemia(MI)rats.Methods:SD rats were randomly divided into four groups:control group,MI model group,Neiguan(PC6)point group(EA group)and non-acupoint(the lateral-superior side of the hip)group.Myocardial infarction was produced in rats with 85 mg/kg of isoproterenol administered subcutaneously twice at an interval of 24 h.Rats of EA group and non-acupoint group were treated with electroacupuncture,once daily for five consecutive days.Gene chip was used to detect RAS-related genes of myocardial tissue from the model group and the EA group.Cardiac index and pathological staining were observed of four groups.Real-time quantitative fluorescent PCR was used to detect the expression of AGT mRNA in cardiac tissue.Results:The expression of RAS-related genes were different between the model group and the EA group.The difference of AGT mRNA was the most significant.The cardiac index and AGT mRNA expression in the model group were significantly higher than those in the control group(P<0.01).While those in the EA group were significantly lower than model group(P<0.05).The cardiac index and the expressions of AGT mRNA in the nonacupoint group were significantly higher than those in the EA group(P<0.01),and there was no difference with the model group.Conclusion:Electroacupuncture along meridians can improve myocardial ischemia in rats,and its mechanism may be related to the down-regulation of AGT mRNA expression in myocardial tissue.

湄潭白茶多糖对金黄色葡萄球菌的抑菌活性及其稳定性

目的:研究湄潭白茶多糖对金黄色葡萄球菌的体外抑菌活性及其稳定性。方法:采用牛津杯法和微量肉汤稀释法测定湄潭白茶多糖对金黄色葡萄球菌的抑菌活性及最小抑菌浓度(Minimum inhibitory concentration,MIC),并进一步探讨温度、pH、紫外线照射和金属离子对其抑菌活性稳定性的影响。结果:湄潭白茶多糖对金黄色葡萄球菌具有抑菌活性,其MIC为8 mg/mL。对湄潭白茶多糖进行抑菌稳定性实验,以金黄色葡萄球菌的OD_(600)值为指标进行分析。结果表明,湄潭白茶多糖在20~60℃时抑菌活性保持稳定,但经高温度(80~100℃)处理后,抑菌活性略有下降,相比4℃实验组抑菌活性保留约45.8%;在pH4~10抑菌活性保持稳定;经30 W紫外线处理10~50 min后,抑菌活性无显著变化(P>0.05);在0.1 mol/L Na^(+)、K^(+)处理下,抑菌活性稳定,但在0.1 mol/L Ca^(2+)处理下,抑菌活性丧失。结论:湄潭白茶多糖对金黄色葡萄球菌具有稳定的体外抑菌活性,为其作为天然防腐剂的开发提供依据。

Sensitivity and vulnerability of water resources in the arid Shiyang River Basin of Northwest China

The sensitivity and vulnerability of water resources to climate change is difficult to assess. In this study, we used a conceptual hydrologic model to investigate the sensitivity of streamflow to climate change. We also pro- posed a framework to evaluate the vulnerability of water resources in arid regions. We applied this framework to a case study of the Shiyang River Basin in Northwest China. Results showed that the precipitation and streamflow in Shiyang River Basin exhibited no significant trends of change from 1956 to 2010. In the past five decades, however, the temperature increased significantly by 0.37℃ per decade. According to the sensitivity assessment, a 10% in- crease in precipitation and a 1℃ increase in temperature altered mean annual streamflow by averages of 14.6% and -0.5%, respectively, from 1988 to 2005. In the 2000s, the calculated vulnerability of water resources in Shiyang River Basin was more than 0.95, indicating severe vulnerability. The increase in the amount of precipitation and the imple- mentation of water-saving measures can reduce the vulnerability of water resources in the future; if precipitation in- creases by 10% per decade and the use of irrigation water decreases by 15% in the 2030s, the evaluated value of water resources vulnerability will be reduced to 0.79. However, the region remains highly vulnerable. The proposed framework for vulnerability assessment can be applied to the arid regions in Northwest China, and the results of our efforts can identify adaptation strategies and improve the management of water resources in such regions.

Green recycling of short-circuited garnet-type electrolyte for high-performance solid-state lithium batteries

Solid-state lithium batteries(SSLBs)solve safety issues and are potentially energy-dense alternatives to next-generation energy storage systems.Battery green recycling routes are responsible for the widespread use of SSLBs due to minimizing environmental contamination,reducing production costs,and providing a sustainable solution for resources,e.g.,saving rare earth elements(La,Ta,etc.).Herein,a solid-state recycling strategy is proposed to achieve green recycling of the crucial component solidstate electrolytes(SSEs)in spent SSLBs.The short-circuited garnet Li_(6.5)La_(3)Zr_(1.5)Ta_(0.5)O_(12)(LLZTO)is broken into fine particles and mixed with fresh particles to improve sintering activity and achieve high packing density.The continuous Li absorption process promotes sufficient grain fusion and guarantees the transformation from tetragonal phase to pure cubic phase for high-performance recycled LLZTO.The Li-ion conductivity reaches 5.80×10^(-4)S cm-1with a relative density of 95.9%.Symmetric Li cell with asrecycled LLZTO shows long-term cycling stability for 700 h at 0.3 mA cm^(-2)without any voltage hysteresis.Full cell exhibits an excellent cycling performance with a discharge capacity of 141.5 mA h g^(-1)and a capacity retention of 92.1%after 400 cycles(0.2C).This work develops an environmentally friendly and economically controllable strategy to recycle SSE from spent SSLBs,guiding future directions of SSLBs large-scale industrial application and green recycling study.

Microstructure and properties of pure iron/copper composite cladding layers on carbon steel

In the present study, pure iron/copper composite metal cladding was deposited onto carbon steel by tungsten inert gas welding. The study focused on interfacial morphological, microstructural, and mechanical analyses of the composite cladding layers. Iron liquid–solid-phase zones were formed at copper/steel and iron interfaces because of the melting of the steel substrate and iron. Iron concentrated in the copper cladding layer was observed to exhibit belt, globule, and dendrite morphologies. The appearance of iron-rich globules indicated the occurrence of liquid phase separation（LPS） prior to solidification, and iron-rich dendrites crystallized without the occurrence of LPS. The maximum microhardness of the iron/steel interface was lower than that of the copper/steel interface because of the diffusion of elemental carbon. All samples fractured in the cladding layers. Because of a relatively lower strength of the copper layer, a short plateau region appeared when shear movement was from copper to iron.

Development of phosphonate-terminated magnetic mesoporous silica nanoparticles for pH-controlled release of doxorubicin and improved tumor accumulation

In this study,phosphonate-terminated magnetic mesoporous nanoparticles(pMMSNs)was designed by incorporation of MNPs in the center of mesoporous silica nanoparticles(MSNs)and followed by grafting phosphonate group on to the surface of MMSNs.The carrier exhibited a typical superparamagnetic feature and the saturation magnetization was 4.89 emu/g measured by vibrating sample magnetometer(VSM).pMMSNs had a spherical morphology and a pore size of 2.2 nm.FromN2 adsorption-desorption analysis,pMMSNs had a surface area of 613.4 m^(2)/g and a pore volume of 0.78 cm^(3)/g.Phosphonate modification improved the colloidal stability of MMSNs,and the hydrodynamic diameter of pMMSNs was around 175 nm.The hydrophilic phosphonate group significantly enhanced the negative surface charge of MMSNs from -19.3 mV to -28.8 mV pMMSNs with more negative surface charge had a 2.3-fold higher drug loading capacity than that of MMSNs.In addition,the rate and amount of release of doxorubicin(DOX)from DOX/pMMSNs was pH-dependent and increased with the decrease of pH.At pH 7.4,the release amount was quite low and only approximately 17wt%ofDOXwasreleasedin48h.AtpH5.0and3.0,the release rate increased significantly and the release amount achieved 31 wt%and 60 wt%in 48 h,respectively.To evaluate the magnetic targeting performance ofpMMSNs,FITC labeledpMMSNswas injected into mice bearing S180 solid tumor.FITC labeledpMMSNscontrolled by an external magnetic field showed higher tumor accumulation and lower normal tissue distribution.

Mechanical Properties and Microstructure of 6082-T6 Aluminum Alloy Joints by Self-support Friction Stir Welding

The majority of this research has concentrated on developing the self-support friction stir welding（SSFSW） tool which consists of a big concave upper shoulder and a small convex lower shoulder, and procedures for making reliable welds in aluminum hollow extrusion. The 5-mm-thick 6082-T6 aluminum alloy was self-support friction stir welded at a constant tool rotation speed of 800 r/min. The effect of welding speed on microstructure and mechanical properties was investigated. The results of transverse tensile test indicated that the tensile strength of joints increased and the elongation decreased with increasing welding speed. The whole values of microhardness of SSFSW joints increased with increasing welding speed from 10 to 200 mm/min. The defectfree joints were obtained at lower welding speeds and the tensile fracture was located at the heat-affected zone（HAZ） adjacent to the thermo-mechanically affected zone（TMAZ） on the advancing side. The investigation of the flow pattern of the softened metal around the SSFSW tool revealed that the flow pattern of the softened metal was driven by two shoulders and the stir pin. The failure of specimens in tension presented the ductile fracture mode.

In_(2)O_(3-)x(OH)y/Bi_(2)MoO_(6) S-scheme heterojunction for enhanced photocatalytic performance

Surface heterojunction engineering has been extensively studied to promote efficient charge separation in semiconductor materials.Designing an effective heterojunction system to optimize the separation and transport of photo-induced charges is an appealing strategy to enhance the photocatalytic efficiency.In this work,In_(2)O_(3)-x(OH)y in situ decorated Bi_(2)MoO_(6) two-dimensional step-scheme heterojunctions were synthesized through a controlled dehydroxylation process of indium-based precursors.The charge transfer mechanism of this step-scheme heterojunctions was confirmed by the characterization of electron structures,reactive species,photoelectric properties and DFT theoretical calculation.The band bending and the internal electric field caused by the charge transfer upon hybridization can effectively promote the separation of charges and present the optimal redox capacity.In addition,surface residual hydroxyl groups can regulate the surface energy state and optimize the interfacial charge transfer kinetics of the prepared step-scheme heterojunction.Eventually,the step-scheme heterojunction exhibits superior performance in photocatalytic reduction of hexavalent chromium and degradation of organic pollutants under visible light irradiation.This work provides an innovative perspective to construct photocatalyst with superior activity.

Determination of mechanical properties of Zanthoxylum armatum using the discrete element method

Using the discrete element method to investigate the behavior of particles is a crucial strategy in the research and development of novel equipment.Green pepper(Zanthoxylum armatum)is a globally renewable plant-derived medicinal and food homologous commodity with a wide range of uses and great demand,but the mechanical properties needed to develop its processing equipment are scarce.Thus,this case study aimed to systematically explore the necessary input parameters to model green pepper,and to provide new insights for the guidance of future industrial applications worldwide.On the basis of the experimental measured physical properties,the contact properties of green pepper on zinc-coated steel were first calibrated and then used to determine the contact properties between particles.The differences between the experimental and simulation results were analyzed for selection and verification of the contact properties accurately.Difference analysis confirmed that the co-efficient of restitution,coefficient of static friction and coefficient of rolling friction for contact between the particle and zinc-coated steel have values of 0.392,0.650,and 0.168,and those coefficients for particle-to-particle contact have values of 0.199,0.710,and 0.184,respectively.Discoveries in this work may contribute to the research and development of production equipment for green pepper.

背应力平衡策略实现非均质Al-SiC复合材料的强塑性协同

高强复合材料的低位错存储性能及其引发的强塑倒置问题阻碍了该系列材料的进一步发展.本文通过新颖的形变驱动冶金方法,设计了一种巧妙的具有粗细晶粒异质结构的纳微混合SiC增强铝基复合材料.基于背应力理论对累积的几何必须位错和晶内分散的SiC颗粒进行调控,使得背应力与外在施加应力保持动态平衡.这是本策略实现材料强塑性协同的关键.所设计的SiC_(5np-5μp)/Al复合材料的极限抗拉强度和均匀伸长率分别为324 MPa和12.9%,达到SiC_(10μp)/Al抗拉强度的181%,而塑性仅损失了约3%.因此,本文提供了一种基于背应力优化的强度-塑性协同新策略.

Effects of electroacupuncture on rats with cognitive impairment:An iTRAQ-based proteomics analysis

Objective The study explores the effects of electroacupuncture(EA)at the governing vessel(GV)on proteomic changes in the hippocampus of rats with cognitive impairment.Methods Healthy male rats were randomly divided into 3 groups:sham,model and EA.Cognitive impairment was induced by left middle cerebral artery occlusion in the model and EA groups.Rats in the EA group were treated with EA at Shenting(GV24)and Baihui(GV20)for 7 d.Neurological deficit was scored using the Longa scale,the learning and memory ability was detected using the Morris water maze(MWM)test,and the proteomic profiling in the hippocampus was analyzed using protein-labeling technology based on the isobaric tag for relative and absolute quantitation(iTRAQ).The Western blot(WB)analysis was used to detect the proteins and validate the results of iTRAQ.Results Compared with the model group,the neurological deficit score was significantly reduced,and the escape latency in the MWM test was significantly shortened,while the number of platform crossings increased in the EA group.A total of 2872 proteins were identified by iTRAQ.Differentially expressed proteins(DEPs)were identified between different groups:92 proteins were upregulated and 103 were downregulated in the model group compared with the sham group,while 142 proteins were upregulated and 126 were downregulated in the EA group compared with the model group.Most of the DEPs were involved in oxidative phosphorylation,glycolipid metabolism and synaptic transmission.Furthermore,we also verified 4 DEPs using WB technology.Although the WB results were not exactly the same as the iTRAQ results,the expression trends of the DEPs were consistent.The upregulation of heat-shock proteinβ1(Hspb1)was the highest in the EA group compared to the model group.Conclusion EA can effect proteomic changes in the hippocampus of rats with cognitive impairment.Hspb1 may be involved in the molecular mechanism by which acupuncture improves cognitive impairment.

Lightweight Design:Friction‑Based Welding between Metal and Polymer

The heterojunctions between metal and polymer have become the effective ways to produce the lighter,safer and more environmental friendly vehicles for the manufacturing fields of automotive and aerospace.The state-of-the-art frictionbased welding techniques are characterized by low peak temperature,severe plastic deformation,energy efficiency and nonpollution,which can simultaneously realize the mechanical and chemical bonding,improving mechanical performances.In this review,the current progress about friction-based welding techniques is summarized,containing technical development,welding tool design,microstructural characteristic,process optimization,surface modification and joining mechanism.The conclusions and prospects are presented,which focus on the practical implications for the manufacturing sectors and recommendations for further research and development.The purpose of this review is to elucidate the benefits of friction-based welding techniques so that these methods may be better exploited and industrialized.

Simultaneous Approximation Ratios for Parallel Machine Scheduling Problems

Motivated by the problem to approximate all feasible schedules by one schedule in a given scheduling environment,we introduce in this paper the concepts of strong simultaneous approximation ratio and weak simultaneous approximation ratio.Then we study the two variants under various scheduling environments,such as non-preemptive,preemptive or fractional scheduling on identical,related or unrelated machines.