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Journal of Central south University 2015年第2期22卷 638-645页

作者：范祥 KULATILAKE P H s W 陈新曹平 school of Resources and safety Engineering Central South University Rock Mass Modeling and Computational Rock Mechanics Laboratories University of Arizona school of Mechanics and Civil Engineering China University of Mining and Technology (Beijing)

The ratio of crack initiation stress to the uniaxial compressive strength(sCI,B/sUC,B) and the ratio of axial strain at the crack initiation stress to the axial strain at the uniaxial compressive strength(B,UCB,CI,A,A/ssss) were studied by performing numerical stress analysis on blocks having multi flaws at close spacing's under uniaxial loading using PFC3 D. The following findings are obtained: sCI,B/sUC,B has an average value of about 0.5 with a variability of ± 0.1. This range agrees quite well with the values obtained by former research. For joint inclination angle, β=90°,B,UCB,CI,A,A/ssss is found to be around 0.48 irrespective of the value of joint continuity factor, k. No particular relation is found betweenB,UCB,CI,A,A/ssss and β; however, the average B,UCB,CI,A,A/ssss seems to slightly decrease with increasing k. The variability ofB,UCB,CI,A,A/ssss is found to increase with *** on the cases studied in this work,B,UCB,CI,A,A/ssss ranges between 0.3 and 0.5. This range is quite close to the range of 0.4to 0.6 obtained for sCI,B/sUC,B. The highest variability of ± 0.12 forB,UCB,CI,A,A/ssss is obtained for k=0.8. For the remaining k values the variability ofB,UCB,CI,A,A/ssss can be expressed within ± 0.05. This finding is very similar to the finding obtained for the variability of sCI,B/sUC,B.

关键词： jointed rock multi flaws uniaxial loading PFC3D model crack initiation stress(sCI B) axial strain at crack initiation

Arsenic removal from water by iron-sulphide minerals

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Chinese science Bulletin 2000年第15期45卷 1430-1434页

作者： William s.Fyfe Department of Earth sciences the University of Western OntarioLondonOntario N6A 5B7Canada

n bench-scaled experiments, iron-sulphide minerals, pyrite and pyrrhotite are used as adsorbents for arsenic removal from As-spiked water of As5+ and As3+ species. The adsorption rate, efficiency, As-adsorption stability and the associated pH conditions have been examined. Observations indicate that these iron-sulphide minerals are very efficient to adsorb arsenic from water for both As5+ and As3+ species. similar to other studies, As3+-adsorption shows a slower rate than As3+. The stability of the adsorbed arsenic seems closely related to the pH values of the solution. A lower pH level commonly less than 4.0 is required to protect the adsorbed arsenic from serious oxidation and backward release. Fining of the mineral powders and shaking of the solution during adsorption enhance the adsorption efficiency and adsorption rate. For practical use of the method presented in this study, the waste produced should be managed with great care to keep it from redistribution over water system. A further study of

关键词： arsenic contamination arsenic removal iron-sulphide minerals.

Effects of atmospheric gases on terrestrial plants and critical levels of air pollution

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Journal of Environmental sciences 1992年第1期4卷 10-14页

作者： s.M.semenov Natural Environment and Climate Monitoring Laboratory Moscow 107258 Glebovskaya 20b LAM

An integrated approach was developed to determine the critical levels of air pollution for ecological standard setting based on the unified index of biological response, by taking into account the effects of all pollution components simultaneously. An empirical model of plant productivity was taken as the dose response model for gaseous pollutant effect on the productivity of trees and the annual productivity of plants was used as the above mentioned index. The CO2 increase in the lower atmosphere was considered to potentially increase plant productivity and NO2 was estimated as neutral while being dangerous for plants as a chemical precursor of ozone or as a source of acidification. The maximum permissible chronic O3 and sO2 levels for trees were estimated and it was found that O3 is much more phytotoxic, as compared to sO2 , with a rather narrow range of permissible levels (27-33 ppb) which complicates its monitoring and control.

关键词： air pollution biological responses terrestrial plants.

Epstein-Barr virus at 50——future perspectives

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Chinese Journal of Cancer 2014年第11期33卷 527-528页

作者： Lawrence s.Young Warwick Medical school University of WarwickCoventryCV4 7ALUK

The special November and December issues of the Chinese Journal of Cancer celebrate the 50th anniversary of the discovery of Epstein-Barr virus(EBV) with a series of reviews covering the association of the virus with various cancers, with special emphasis on the role of EBV in the pathogenesis of nasopharyngeal cancer(NPC). The restricted geographic prevalence of NPC along with the tumor's consistent association with EBV infection has fascinated scientists and clinicians ever since it was first suggested in 1966. As in all cancers, NPC development reflects the complex interplay between host genes and environmental factors, but the essential role of EBV infection provides important insight into the etiology of this tumor. Indeed, it is this understanding that is now translating into exciting diagnostic and therapeutic opportunities.

关键词： Epstein-Barr病毒病毒感染 NPC 发病机制 EB病毒临床医生相互作用环境因素

H2A.Z at the Core of Transcriptional Regulation in Plants

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Molecular Plant 2018年第9期11卷 1112-1114页

作者： s. Vinod Kumar Cell and Developmental Biology Department John Innes Centre Norwich NR4 7UH UK

H2A.Z, an evolutionarily conserved variant form of canonical H2A, has been widely recognized to have decisive roles in multi- ple cellular processes through its influence on chromatin structure and dynamics in eukaryotes. Many of its effects on regulating chromatin function have been attributed to its role in modulating nucleosome dynamics and DNA methylation. In plants, H2A.Z plays critical roles in multiple processes, such as growth and development, phase transitions, and response to the environment. Despite the progress made in understanding its role in these processes, several aspects of H2A.Z biology.

关键词： ARABIDOPsIs ACTIVATION EXPREssION

Noise and vibration measurements in a Viking military vehicle

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Defence Technology（防务技术） 2021年第6期17卷 1976-1987页

作者： Gurmail s.Paddan Marietta L.L.McIlraith Institute of Naval Medicine Crescent RoadAlverstokeHampshirePO122DLUK Formerly at Institute of Naval Medicine Crescent RoadAlverstokeHampshirePO122DLUK

Noise and whole-body vibration measurements were made in a Viking military vehicle to determine the variation that should be expected during repeat measures,the effect of speed(up to 60 km/h in 5 km/h increments),and during travel over different types of terrain(comprising concrete road,gravel track and rough cross-country).Measurements were made at various crew positions(including the driver and commander)in both the front and the rear cabs in the *** translational axes of vibration were measured in each *** speeds were investigated over road(35 km/h and 55e60 km/h)and gravel(20 km/h and 35 km/h)*** effect of varying speed of the vehicle on the measured noise and vibration magnitudes was also *** highest sound pressure level(LAeq)of 104 dB(A)was measured at the commander’s standing position during travel over concrete road at 55 km/*** noise levels occurred for a standing commander compared with when sitting on the seat.A maximum single axis frequency-weighted vibration magnitude of 1.0 m/s^(2) *** measured on the driver’s seat during travel over track at 35 km/*** vibration magnitudes occurred during travel over track compared with travel over *** noise and vibration exposure of crew within the Viking vehicle increased with increasing speed of the vehicle.

关键词： Noise Whole-body vibration Vibration dose value Viking military vehicle

Mechanical properties and in vivo biodegradability of Mg-Zr-Y-Nd-La magnesium alloy produced by a combined severe plastic deformation

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Rare Metals 2021年第3期40卷 651-662页

作者： A.Torkian G.Faraji M.s.Pedram school of Mechanical Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran Department of Veterinary surgery and Radiology Faculty of Veterinary MedicineUniversity of Tehran14199-63111Iran

Permanent implants are going to be replaced by the implementation of biodegradable magnesium-based implants in fixation of internal bone fractures because of many concerns associated with conventional ***,biodegradable magnesium-based biomaterials exhibit higher biodegradation rate and low mechanical properties which are the main *** work aims to almost overcome both disadvantageous by grain refining of a WE43 magnesium alloy containing 93.04 wt% Mg,4.12 wt% Y,2.15 wt% Nd,0.43 wt% Zr,and 0.26 wt%*** this study,the consequences of combined severe plastic deformation(sPD) on the mechanical properties,microstructure,and in vivo degradation behavior of WE43 magnesium alloy were *** do so,WE43 magnesium alloy was chosen and processed through multipass equal channel angular pressing(ECAP) at 330℃ for up to four passes followed by an extrusion *** results showed that higher strength and hardness with minimum ductility less was obtained in the sample processed via two-pass ECAP followed by *** vivo biodegradation experiments showed higher degradation rate for the unprocessed coarse-grained(CG) WE43 *** two-pass ECAP and extruded sample with ultrafine-grained(UFG) structure exhibited the lowest in vivo biodegradation rate besides appropriate mechanical *** may be concluded that the WE43 magnesium alloy processed via two-pass ECAP and extrusion could be a very promising candidate for biodegradable implants from both mechanical and biocorrosion viewpoints.

关键词： Implant severe plastic deformation WE43 Grain refinement Hardness Mechanical properties

Impact of the aqueous extract of dandelion, probiotic and their synbiotic on male lamb’s testicular histopathology relative to semen characteristics

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Open Journal of Animal sciences 2014年第1期4卷 23-30页

作者： Moustafa Zeitoun Mohamed Farahna Khaled al-sobayil Ahmed Abdel-salam College of Applied Medical sciences Qassim University Qassim KSA Department of Animal Production and Breeding Qassim University Buriedah KSA Department of Food sciences and Human Nutrition College of Agriculture and Veterinary Medicine Qassim University Buriedah KSA

This study aimed at investigating effects of dandelion/probiotic on the testis histology and semen characteristics of male lambs. Twelve prepuberal Noemi male lambs (2 ± 0.4-month-old and 20 ± 3.5 kg B.W) were randomly allocated into four groups. Animals in group 1 were controlled, orally given normal saline as the same schedule of treated animals. In group 2 animals were given daily oral 50 ml of an aqueous extract of dandelion leaves. In group 3 animals were given a daily 50 ml of cow’s milk probiotics, and in group 4 animals were given 50 ml of a 1:1 mixture (dandelion extract: probiotic). Animals were treated for 8 consecutive weeks. At puberty, semen ejaculates were collected weekly for further 10 weeks. Thereafter, animals were sacrificed and testicles were obtained, weighed and a histopathological study was performed on the testis. Results revealed that oral administration of the dandelion aqueous extract to prepuberal lambs exhibited disturbances in the histological architecture of the testicular semeniferous tubules. Additionally, dandelion resulted in edematic interstitial tissues with evident vaculations. These deteriorations were reflected in less spermatogenesis (i.e. less sperm concentration and ejaculate volume by 10% and 20%, respectively than controlled group). also, the percentage of sperm progressive motility was lower (P sperm was higher (P s given dandelion than control. Administration of probiotic hasn’t revealed a change in the seminiferous tubules architecture, however, very little vaculation with rare edema was observed. Administration of the synbiotic mixture revealed intermediate histopathological appearances. The highest sperm concentration, testosterone concentration and advanced motility were obtained when probiotic was administered. In conclusion, although dandelion cures some hepatic malfunctions in human, caution must be taken into consideration of the frequent ingestion of dandelion for its harmful eff

关键词： Dandelion Histopathology Probiotic Ram semen Testis

Chemotactic signaling and beyond: link between interleukin-16 and axonal degeneration in multiple sclerosis

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Neural Regeneration Research 2015年第11期10卷 1761-1763页

作者： Dusanka s.skundric Department of Immunology and Microbiology School of MedicineWayne State University

Multiple sclerosis（Ms）is a progressive inflammatory,and chronic demyelinating,neurodegenerative disease of central nervous system（CNs）.Autoimmune responses to myelin and other CNs antigens mediated by cluster of differentiation 4（CD4＋）T cells are critical for initiation and progression of *** of autoimmune T cells from the peripheral lymph organs into CNs parenchyma leads to inflammation,demyelination and damage of axonal cytoskeleton, which manifest in decreased impulse conduction velocity of motor and sensory nerves. Myelin and axonal pathology causes motor, sensory and autonomic nerve dysfunction, including optic nerve damage leading to double or distorted vision; paresis and paralysis of extremities, painful sensations, and bladder sphincter dysfunction, manifested as bladder incontinence. Gray matter pa- thology in cortical and subcortical regions, including cerebellum and hippocampus underlies cognitive and behavioral dysfunction consisting of memory deficits, depression, and ataxic gait and tremor.

关键词： cell IL Chemotactic signaling and beyond link between interleukin-16 and axonal degeneration in multiple sclerosis EAE MOG

Photonic crystal ring resonator based add-drop filter using hexagonal rods for CWDM systems

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Optoelectronics Letters 2011年第3期7卷 164-166页

作者： Robinson s Nakkeeran R Department of Electronics and Communication Engineering Pondicherry Engineering College

In this paper,theoretical analysis of two-dimensional photonic crystal ring resonator(2D PCRR) based add-drop filter(ADF) is presented for coarse wavelength division multiplexing(CWDM) system to drop a channel at 1511 nm using hexagonal rods that are positioned in the square *** 2D finite difference time domain(2D FDTD) method and plane wave expansion(PWE) method are used for obtaining the filter response and band structure of the filter *** to 100 dropping and coupling efficiencies at 1511 nm and 16 nm of bandwidth are observed through *** is very well meeting the requirement of ITU-T G.694.2 standard,which is specified for metro access and short haul optical *** overall size of the proposed filter is 11.4 μm×11.4 μ*** can also be used in integrated optics.

关键词：二维光子晶体 WDM系统滤波器谐振环纳米通道时域有限差分粗波分复用平面波展开