Numerical modelling of stress analysis around rectangular tunnels with large discontinuities(fault) by a hybridized indirect BEM

Tunnels are one of the major transportation routes to pass mountains and difficult geological conditions. The behavior of these structures is significantly influenced by rock mass and discontinuities. Orientation of discontinuities is one of the most important geometrical parameters affecting discontinuities behavior. The effect of large discontinuities(faults) behavior on a jointed medium around rectangular tunnels is studied. A hybridized indirect boundary element code named TFSDDM(fictitious stress displacement discontinuity method) is used to study the stress distribution around the tunnels excavated in jointed rock masses. The code uses advantages of both fictitious stress and displacement discontinuity methods to analyze discontinuity effects more accurately. Results show that the dip angle of discontinuities has significant effect on stress distribution around the tunnel. It is also shown that increase in the discontinuities dip angle located in the roof will result in decrease in tensile stress of the roof. Stresses reaches to 8 MPa in the roof while due to dilation effect they reach up to 13 MPa.

Effect of Colchicine on Total Antioxidant Capacity,Antioxidant Enzymes and Oxidative Stress Markers in Patients with Knee Osteoarthritis

Background/Aim: We aimed to investigate the effects of colchicine on clinical recovery, as well as oxidative stress markers and total antioxidant capacity (TAC) in whole blood of patients with knee osteoarthritis (OA). Materials and methods: Sixty patients with grade 2 - 3 knee OA according to ACR knee OA criteria whom examination of the knee joint synovial fluid by polarized light microscopy demonstrated CPDD crystals existence were included in the study. Fifty healthy subjects were included as a control group. Patients were divided randomly into two groups. The first group (paracetamol group) was given only paracetamol 3 gr daily p.o and the second group (colchicine and paracetamol group) was given colchicine 1,5 gr and paracetamol 3 gr daily p.o for six months. For outcome measures WOMAC and VAS were used. Superoxide dismutase (SOD), Catalase (CAT) ezyme activities and Glutathione (GSH) and Malondialdehyde (MDA) levels and TAC all were measured. Results: WOMAC scores were improved in both patient groups compared with pre-treatment evaluation (p 0.05). TAC was signifcantly increased only in colchicine/paracetamol group. Oxidant parameter MDA levels were significantly decreased in both paracetamol group and colchicine/paracetamol group. CAT, SOD enzyme activities and GSH levels did not change before and after treatment protocols in both patient groups. Conclusion: Both paracetamol 3000 mg/day and 3000 mg paracetamol plus 1,5 gr/day colchicine is effective in the treatment of patients with knee osteoarthritis. But the addition of colchicine to paracetamol produced significantly greater symptomatic benefit than paracetamol alone. Our study also showed that colchicine lowers whole blood MDA which is a lipid peroxidation compound and elevates TAC levels in patients with knee OA. This may show probable disease modifying effect of colchicine in knee OA which require further long period laboratory and radiologic investigations.

Induction of endoplasmic reticulum-derived oxidative stress by an occult infection related S surface antigen variant

AIM: To investigate the mechanism of endoplasmic reticulum(ER) stress induction by an occult infection related hepatitis B virus S surface antigen(HBsAg)variant.METHODS: We used an HBsAg variant with lower secretion capacity, which was a KD variant from a Korean subject who was occultly infected with the genotype C. We compared the expression profiles of ER stress-related proteins between HuH-7 cells transfected with HBsAg plasmids of a wild-type and a KD variant using Western blot.RESULTS: Confocal microscopy indicated that the KD variant had higher levels of co-localization with ER than the wild-type HBsAg. The KD variant upregulated ER stress-related proteins and induced reactive oxygen species(ROS) compared to the wildtype via an increase in calcium. The KD variant also down-regulated anti-oxidant proteins(HO-1, catalase and SOD) compared to the wild-type, which indicates positive amplification loops of the ER-ROS axis. The KD variant also induced apoptotic cell death via the upregulation of caspase proteins(caspase 6, 9 and 12).Furthermore, the KD variant induced a higher level of nitric oxide than wild-type HBsAg via the up-regulation of the iNOS protein.CONCLUSION: Our data indicate that occult infection related HBsAg variants can lead to ER-derived oxidative stress and liver cell death in HuH-7 cells.

Determination of Mechanical Properties of Micromembranes with Compressive Residual Stress

A novel model of a load-deflection method to determine the mechanical properties of micromembranes with compressive residual stress is described. Since thin film structures are frequently used in micro devices, characterisation of mechanical properties of thin films is desired by the design and fabrication of micromachines. In this paper, the mechanical properties of thin micromembranes under compressive stress are characterised, which are fabricated by bulk micromachining. The relation between the center deflection and the load pressure on a square membrane is deduced by modelling the membrane as an elastic plate having large deflection with clamped boundaries. According to the model, whether the membrane has initial deflection or not has no effect on the measurement result. The Young's modulus and residual stress are simultaneously determined. The mechanical properties of siliconoxide, silicon nitride membranes and composite membranes of polysilicon with silicon nitride are measured.[

Approaches to College English Pronunciation Teaching

In most universities in China,pronunciation has long been overlooked in college English teaching.With the reform of college English teaching,great attention has been paid to the cultivation of the students' listening and speaking skills,that is,Eng lish teaching has moved to language functions and communicative competencies,a new urgency for the teaching of pronuncia tion has arisen.This paper covers the four areas of pronunciation:sounds,stress,rhythm,and intonation,with the expectation that it will provide readers with comprehensive insight into ways of teaching pronunciation.

数字政府治理评估:理论框架与指标设计

数字政府作为信息技术革命驱动下产生的一种新型政府形态,其内在逻辑表现为以技术创新撬动政府治理变革,呈现出扁平化的组织结构、数据化的信息技术、多元化的治理主体以及以公众为中心的明显特征。本文聚焦于如何实现数字政府治理评估体系构建,尝试基于全面质量管理思想,围绕数字政府建设搭建契合于研究的STRE模型,即从制度供给、技术创新、资源管理及公众体验四方面着手,围绕四个维度细化各级指标,最终构建16个二级指标和33个三级指标。鉴于上述分析,本文在全面把握数字政府治理内在逻辑和评估框架的基础上,尝试设计科学合理的数字政府治理评估指标体系,这对于持续推进数字政府治理建设具有重要的理论价值与现实意义。

Redox regulation of the immune response

The immune-inflammatory response is associated with increased nitro-oxidative stress.The aim of this mechanistic review is to examine:(a)the role of redox-sensitive transcription factors and enzymes,ROS/RNS production,and the activity of cellular antioxidants in the activation and performance of macrophages,dendritic cells,neutrophils,T-cells,B-cells,and natural killer cells;(b)the involvement of high-density lipoprotein(HDL),apolipoprotein A1(ApoA1),paraoxonase-1(PON1),and oxidized phospholipids in regulating the immune response;and(c)the detrimental effects of hypernitrosylation and chronic nitro-oxidative stress on the immune response.The redox changes during immune-inflammatory responses are orchestrated by the actions of nuclear factor-κB,HIF1α,the mechanistic target of rapamycin,the phosphatidylinositol 3-kinase/protein kinase B signaling pathway,mitogen-activated protein kinases,5'AMP-activated protein kinase,and peroxisome proliferator-activated receptor.The performance and survival of individual immune cells is under redox control and depends on intracellular and extracellular levels of ROS/RNS.They are heavily influenced by cellular antioxidants including the glutathione and thioredoxin systems,nuclear factor erythroid 2-related factor 2,and the HDL/ApoA1/PON1 complex.Chronic nitro-oxidative stress and hypernitrosylation inhibit the activity of those antioxidant systems,the tricarboxylic acid cycle,mitochondrial functions,and the metabolism of immune cells.In conclusion,redox-associated mechanisms modulate metabolic reprogramming of immune cells,macrophage and T helper cell polarization,phagocytosis,production of pro-versus anti-inflammatory cytokines,immune training and tolerance,chemotaxis,pathogen sensing,antiviral and antibacterial effects,Toll-like receptor activity,and endotoxin tolerance.

Hot deformation behavior and microstructure evolution of TiC–Al_2O_3/Al composites

Hot compression behavior of TiC–Al2O3/Al composites was studied using the Gleeble-1500 system at a temperature range of 300–550 °C and at strain rate range of 0.01–10.00 s-1. The associated structural changes were studied by TEM observations. The results show that stress level decreases with deformation temperature increasing and strain rate decreasing, which can be represented by a Zener–Hollomon parameter in an exponent-type equation with hot deformation activation energy Q of 172.56 kJ·mol-1.Dynamic recovery occurs easily when strain rates are less than 10.00 s-1. Dynamic recrystallization can occur at strain rate of 10.00 s-1.

教育电视在新媒体环境下的生存与发展策略

(接上期)三、网络电视网络的出现及其快速发展给风光了40多年的电视带来了巨大的冲击,最先享受数字技术成果的互联网传播媒介显现出多媒体、全球性、大容量、交互性、开放性和可检索性等崭新的优势,从而映衬出电视传播的缺陷。利用计算机作为接收终端,借助互联网络,出现了网络直播或点播的网络电视,这是新媒体和数字技术应运而生的又一个新兴产物。1、网络电视概念及组成。

Registrations That Must Be Handled for the Export of Chemicals to China-Ⅲ

3.Administration of precursors and chemicals used in production of narcotic drugs and psychotropic substances To perform the commitments stipulated in the "United Nations Convention against Il-licit Traffic in Narcotic Drugs and Psycho-tropic Substances",strengthen the adminis-tration of precursors and chemicals used inproduction of narcotic drugs and psychotro-

Air Liquide Posts H1 Records

Air Liquide announced the revenue for thefirst half of 2009 reduced slightly by 6.8%,to Euro 5.937 billion, half of which is at-tributable to the decline in natural gas prices.The net profit was Euro 596 million, al-most at the same level as the first half2008.

New Setup,Agreement & Plan

Sinopec and MCC Form StrategicBusiness PartnershipChina Petroleum and Chemical Corporation(Sinopec Corp.)andMitsubishi Chemical Corporation(MCC)signed a basic agreement toestablish a strategic business partnership on April 14th.The goal of thepartnership is to use respective advantages in technologies,market,andmaterials,and further strengthen ties between the two parties to speedup business activities.