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mode of action for inorganic arsenic toxicity and carcinogenesis

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Chinese Science Bulletin 2014年第11期59卷 1078-1082页

作者： Puttappa R.Dodmane Lora L.Arnold samuel m.cohen Department of Pathology and microbiology University of Nebraska Medical Center983135 Nebraska Medical Center

Inorganic arsenic(iAs) at high doses is a known human carcinogen, inducing tumors of the skin,urinary bladder, and lung. It is also associated with noncancer toxicities. An understanding of the mode of action(mOA) for arsenic-induced effects is needed to develop a scientifically-based risk assessment. To determine an mOA for iAs induced toxicities, it is necessary to understand the metabolism, kinetics, cell transport, and interaction with specific proteins of iAs. Based on in vitro investigations using animal and human cells, studies from animal models,and clinical and epidemiological studies, we have proposed an mOA involving formation of sufficient levels of reactive trivalent metabolites which interact with critical free sulfhydryl groups, leading to cytotoxicity and regenerative cell proliferation. There is a strong correlation between in vitro cytotoxicity([0.1 lmol/L trivalent arsenicals) and the no effect levels in rodents [approximately 1 ppm(1 ppm = 1 mg/L) of water or diet]. In epithelial target tissues, the cytotoxic effects of iAs result in chronic precursor lesions which have the potential for an increased risk of developing cancer. In non-epithelial tissues, noncancer toxicities such as hypertension and atherosclerosis develop. This mOA implies a non-linear, threshold dose–response relationship for both non-cancer and cancer end points of exposure to iAs.

关键词：体外细胞毒性致癌作用无机砷诱导效应会计准则氧化锌避雷器上皮组织动脉粥样硬化

Review and synthesis of the effects of climate change on amphibians

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Integrative Zoology 2013年第2期8卷 145-161页

作者： Yiming LI Jeremy m.cohen Jason R.ROHR Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Department of Integrative Biology University of South FloridaTampaFLUSA

Considerable progress has been made in understanding the responses of amphibians to climate change,with successful research carried out on climate change-associated shifts in amphibian phenology,elevational distributions and amphibian-parasite *** review and synthesize the literature on this topic,emphasizing acutely lethal,sublethal,indirect and positive effects of climate change on amphibians,and major research *** instance,evidence is lacking on poleward shifts in amphibian distributions and on changes in body sizes and morphologies of amphibians in response to climate *** have limited information on amphibian thermal tolerances,thermal preferences,dehydration breaths,opportunity costs of water conserving behaviors and actual temperature and moisture ranges amphibians *** when much of this information is available,there remains little evidence that climate change is acutely lethal to *** suggests that if climate change is contributing to declines,it might be through effects that are not acutely lethal,indirect,or both,but evidence in support of this suggestion is *** fact,evidence that climate change is directly contributing to amphibian declines is weak,partly because researchers have not often ruled out alternative hypotheses,such as chytrid fungus or climate-fungus ***,we recommend that amphibian-climate research shift from primarily inductive,correlational approach as to studies that evaluate alternative hypotheses for *** additional rigor will require interdisciplinary collaborations,estimates of costs and benefits of climate change to amphibian fitness and populations,and the integration of correlative field studies,experiments on‘model’amphibian species,and mathematical and functional,physiological models.

关键词： amphibian decline Batrachochytrium dendrobatidis breeding date climate-linked epidemic hypothesis global warming

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer m.Colón-mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose m.Santiago samuel E.Ocasio Rivera Dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge D.miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Uncertainty and filtering of hidden markov models in discrete time

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Probability, Uncertainty and Quantitative Risk 2020年第1期5卷 68-101页

作者： samuel N.cohen mathematical Institute University of OxfordWoodstock RoadOxfordUK

We consider the problem of filtering an unseen markov chain from noisy observations,in the presence of uncertainty regarding the parameters of the processes *** the theory of nonlinear expectations,we describe the uncertainty in terms of a penalty function,which can be propagated forward in time in the place of the *** also investigate a simple control problem in this context.

关键词： Filtering Optimal control Robustness Nonlinear expectation

都灵DVB-SH现场试验——描述和测量结果

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世界广播电视 2012年第2期26卷 34-36页

作者： m.cohen Alex（译）法国阿尔卡特－朗讯移动广播公司

从2008年到2009年，在意大利都灵，阿尔卡特－朗讯、意大利广播电视研究中心（RAI）、和记黄浦（H3G）以及Eutelsal密切协作，对采用卫星手持（DVB—SH）技术的数字视频广播进行了现场试验。该试验的主要目的是：在不同的地面路径（室... 详细信息

从2008年到2009年，在意大利都灵，阿尔卡特－朗讯、意大利广播电视研究中心（RAI）、和记黄浦（H3G）以及Eutelsal密切协作，对采用卫星手持（DVB—SH）技术的数字视频广播进行了现场试验。该试验的主要目的是：在不同的地面路径（室内、室外、移动……）下评估DVB—SH系统的性能并实现一种新的无线电规划拓扑。本文在概述DVB—SH系统之后，将重点描述试验以及获得的结果。

关键词： DVB-SH移动广播卫星地面

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医疗放射学中的物理学

国外发光与电光 1976年第6期 8-11页

作者： m.cohen 为中

医疗放射学是医学中的一个分支,研究在诊断和治疗中电离辐射的应用。1895年德国一位物理教授伦琴(***)发现了X射线。在发现X射线时,他首先是从荧光屏(涂了铂氰化钡的玻璃板)上看到他

关键词：放射学荧光粉夜光粉物理学图象射线照相术电子照相术医疗

TRS Scheduling for Improved QoS Performance in Cloud System

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Computers, materials & Continua 2023年第4期75卷 1547-1559页

作者： G.John samuel Babu m.Baskar Department of Computer Science and Engineering School of ComputingCollege of Engineering and TechnologySRM Institute of Science and TechnologyKattankulathurChengalpattuTamilnadu603203India Department of Computing Technologies School of ComputingCollege of Engineering andTechnologySRM Institute of Science and TechnologyKattankulathurChengalpattuTamilnadu603203India

Numerous methods are analysed in detail to improve task schedulingand data security performance in the cloud environment. The methodsinvolve scheduling according to the factors like makespan, waiting time,cost, deadline, and popularity. However, the methods are inappropriate forachieving higher scheduling performance. Regarding data security, existingmethods use various encryption schemes but introduce significant serviceinterruption. This article sketches a practical Real-time Application CentricTRS (Throughput-Resource utilization–Success) Scheduling with Data Security(RATRSDS) model by considering all these issues in task scheduling anddata security. The method identifies the required resource and their claim timeby receiving the service requests. Further, for the list of resources as services,the method computes throughput support (Thrs) according to the number ofstatements executed and the complete statements of the service. Similarly, themethod computes Resource utilization support (Ruts) according to the idletime on any duty cycle and total servicing time. Also, the method computesthe value of Success support (Sus) according to the number of completions forthe number of allocations. The method estimates the TRS score (ThroughputResource utilization Success) for different resources using all these supportmeasures. According to the value of the TRS score, the services are rankedand scheduled. On the other side, based on the requirement of service requests,the method computes Requirement Support (RS). The selection of service isperformed and allocated. Similarly, choosing the route according to the RouteSupport measure (RSm) enforced route security. Finally, data security hasgets implemented with a service-based encryption technique. The RATRSDSscheme has claimed higher performance in data security and scheduling.

关键词： Cloud task scheduling TRS quality of service RSm route security data security SDE RATRSDS

Combining material characterization with single and multi-oxyanion adsorption for mechanistic study of chromate removal by cationic hydrogel

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Journal of Environmental Sciences 2011年第6期23卷 1004-1010页

作者： Irene m.C.Lo samuel C.N.Tang Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina

Cationic hydrogel with magnetic property was synthesized via radical polymerization and its removal capacity of chromate from contaminated water was found to be 200 mg/*** Fourier transform infrared spectroscopy（FT-IR） study,the mechanism of chromate removal by hydrogel was found to be non-specific adsorption,mainly due to ion exchange,as evidenced by the positively charged functional group,trimethyl ammonium-N＋（CH3）3,in the *** were accordingly determined by testing di？erent oxyanion adsorption onto the *** results of the chromate adsorption experiments illustrated that the amount of chromate adsorbed was nearly equal to that of the chloride released from the hydrogel,which is part of the evidence for ion *** and multi-oxyanion adsorption experiments were also performed,and it was demonstrated that ion removal was species independent,but charge dependent,another characteristic of the ion exchange *** was found that the same Langmuir model can be applied to best fit the findings of single and multi-oxyanion adsorption,which further indicates the mechanism of chromate removal is attributed to ion *** view of the above,the background anions compete for adsorption sites with chromate,evidenced by inhibitive chromate removal in the presence of background electrolytes in the batch studies,further echoing the ion exchange mechanism.

关键词： adsorption magnetic hydrogel mechanism ion exchange oxyanion

Global chronostratigraphical correlation table for the last 2.7 million years

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Episodes 2008年第2期31卷 243-247页

作者： Philip Gibbard Kim m. cohen Cambridge Quaternary Department of Geography University of Cambridge Cambridge CB2 3EN England. Utrecht Centre of Geosciences Department of Physical Geography Utrecht University P.O.Box 80.115 3508TC Utrecht The Netherlands.

The table provides a correlation of chronostratigraphical subdivisions of late Cenozoic geological time, spanning the last 2. 7 million years. The formal division of the Quaternary is the responsibility of the International Commission on Stratigraphy＇s （ICS） Subcommission on Quaternary Stratigraphy （SQS）, in partnership with the International Union for Quaternary Research＇s （INQUA） Commission on Stratigraphy and Chronology （SACCOm）. This is the third published version of the chart. Earlier versions are Gibbard et al., 2004, 2005. See http：//***/correlation/ for history.

关键词：地球新生界地质第四纪地质时代