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Seismicity Study of Botswana from 1966 to 2012

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International Journal of Geosciences 2018年第12期9卷 707-718页

作者： Bokani Nthaba Rapelang E. simon Ghebrebrhan m. Ogubazghi Botswana International University of Science and Technology (BIUST) Palapye Botswana Physics Department University of Botswana Gaborone Botswana Department of Earth Sciences Eritrea Institute of Technology Asmara Eritrea

The history of Botswana’s major seismic events has been initiated by two earthquakes that occurred on the 11th of September and 11th of October 1952 with mL Richter magnitudes of 6.1 and 6.7, respectively, in the Okavango Delta Region (ODR). Not much is known and well documented about the seismicity of a larger coverage of Botswana primarily because over the years, local seismic stations were biased to the north-western part of Botswana, to monitor the more seismogenic ODR. The objective of this study is to use data from the International Seismological Centre (ISC) bulletin for the period 1966-2012 to estimate the relative size distribution of seismic events (b-value), the rate of seismic activity (a-value), and associated stress condition prevailing in Botswana to assist in the quest of hazard mitigation. This study shows that micro-seismic activities of magnitude ranging from 1.3 to 5.7 are distributed not only on the northern part of Botswana, but also in other parts of the country such as the Southern (including Kweneng East and West), Central and Eastern Botswana. Based on 327 events extracted from data compiled by the ISC, the frequency-magnitude distribution (FmD) of earthquakes in Botswana from 1966 to 2012 was estimated with b-value and a-value for the entire catalogue found to be 1.2 and 6.3, respectively, implying a region of low stress dominated by small to moderate events. The minimum completeness magnitude (mC), a value that indicates the lowest magnitude above which all seismic events are reliably recorded was found to be 3.8. From this analysis, annual probabilities of occurrence for m4 and m5 events were found to be 67.2% and 4.3%, respectively, while m6 or larger event has an annual probability of 0.3%.

关键词： b-Value Catalogue Completeness magnitude Okavango Delta Region Seismicity

A Survey on Context-Aware Sensing for Body Sensor Networks

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Wireless Sensor Network 2010年第8期2卷 571-583页

作者： Barbara T. Korel simon G. m. Koo 不详

Context awareness in Body Sensor Networks (BSNs) has the significance of associating physiological user activity and the environment to the sensed signals of the user. The context information derived from a BSN can be used in pervasive healthcare monitoring for relating importance to events and specifically for accurate episode detection. In this paper, we address the issue of context-aware sensing in BSNs, and survey different techniques for deducing context awareness.

关键词： Context Awareness Body Sensor Networks Artificial Neural Networks Bayesian Networks Hidden markov models

EFFECT OF DIGITAL ELEVATION mODEL RESOLUTION ON EmPIRICAL ESTImATION OF SOIL LOSS AND SEDImENT TRANSPORT WITH GIS

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International Journal of Sediment Research 2004年第1期19卷 28-36页

作者： simon WU,Jonathan LI,Gordon HUANG,G.m.ZENG Saskatchewan Department of Agriculture Regina Saskatchewan S4S 0B1 Canada Department of Civil Engineering Ryerson University Toronto Ontario m5B 2K3 Canada Faculty of Engineering University of Regina Regina Saskatchewan S4S OA2 Canada neering Hunan University Changsha 410082 Chian

The horizontal accuracy of topographic data represented by digital elevation model (DEm) resolution brings about uncertainties in landscape process modeling with raster GIS. This paper presents a study on the effect of topographic variability on cell-based empirical estimation of soil loss and sediment transport. An original DEm of 10m resolution for a case watershed was re-sampled to three realizations of higher grid sizes for a comparative examination. Equations based on the USLE are applied to the watershed to calculate soil loss from each cell and total sediment transport to streams. The study found that the calculated total soil loss from the watershed decreases with the increasing DEm resolution with a linear correlation as spatial variability is reduced by cell aggregation. The USLE topographic factors (LS) extracted from applied DEms represent spatial variability, and determine the estimations as shown in the modeling results. The commonly used USGS 30m DEm appears to be able to reflect essentia

关键词： Empirical modeling Soil loss DEm Resolution Spatial variability

Current and future applications of magnetic resonance imaging and spectroscopy of the brain in hepatic encepha-lopathy

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World Journal of Gastroenterology 2006年第19期12卷 2969-2978页

作者： VP Bob Graver m Alex Dresner Daniel m Forton Serena Counsell David J Larkman Nayna Patel Howard C Thomas simon D Taylor-Robinson Hepatology Section Division of medicine A St Mary's CampusFaculty of MedicineImperial College LondonSouth Wharf StreetLondon W2 1NYUnited Kingdom Imaging Sciences DepartmentClinical Sciences DivisionFaculty of MedicineImperial College LondonHammersmith HospitalDu Cane RoadLondon W12 0HSUnited Kingdom Imaging Sciences Department Clinical Sciences Division Faculty of MedicineImperial College LondonHammersmith HospitalDu Cane RoadLondon W12 0HSUnited Kingdom Hepatology Section Division of medicine A St Mary's CampusFaculty of MedicineImperial College LondonSouth Wharf StreetLondon W2 1NYUnited Kingdom

Hepatic encephalopathy （HE） is a common neuropsychiatric abnormality, which complicates the course of patients with liver disease and results from hepatocellular failure and/or portosystemic shunting. The manifestations of HE are widely variable and involve a spectrum from mild subclinical disturbance to deep coma. Research interest has focused on the role of circulating gut-derived toxins, particularly ammonia, the development of brain swelling and changes in cerebral neurotransmitter systems that lead to global CNS depression and disordered function. Until recently the direct investigation of cerebral function has been difficult in man. However, new magnetic resonance imaging （mRI） techniques provide a non-invasive means of assessment of changes in brain volume （coregistered mRI） and impaired brain function （fmRI）, while proton magnetic resonance spectroscopy （^1H mRS） detects changes in brain biochemistry, including direct measurement of cerebral osmolytes, such as myoinositol, glutamate and glutamine which govern processes intrinsic to cellular homeostasis, including the accumulation of intracellular water. The concentrations of these intracellular osmolytes alter with hyperammonaemia. mRS-detected metabolite abnormalities correlate with the severity of neuropsychiatric impairment and since mR spectra return towards normal after treatment, the technique may be of use in objective patient monitoring and in assessing the effectiveness of various treatment regimens.

关键词： Hepatic encephalopathy magnetic resonance imaging magnetic resonance spectroscopy Diffusion weighted imaging Arterial spin labeling Functional mRI

Use of prostate-specific antigen testing in medicare beneficiaries:Association with previous evaluation

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Family medicine and Community Health 2017年第2期5卷 109-118页

作者： Gregory S.Cooper Tzuyung Doug Kou mark D.Schluchter Avi Dor Siran m.Koroukian simon P.Kim Division of Gastroenterology University Hospitals Cleveland Medical Center11100 Euclid Ave.ClevelandOH 44106USA Department of Urology University Hospitals Cleveland Medical Center11100 Euclid Ave.ClevelandOH 44106USA Case Comprehensive Cancer Center Wearn BuildingCase Western Reserve University11100 Euclid Ave.ClevelandOH 44106USA Department of Epidemiology and Biostatistics School of MedicineWood BuildingCase Western Reserve University10900 Euclid Ave.ClevelandOH 44106USA Department of Health Policy and management Milken Institute School of Public HealthGeorge Washington University950 New Hampshire Ave.NWWashingtonDC 20052USA

Objective:Determine uptake of prostate-specific antigen(PSA)testing in medicare benefi-ciaries according to previous receipt of PSA ***:A 5%random sample of men aged 67 years or older without a previous diagnosis of prostate cancer was identified through 2009-2012 medicare *** measured the annualized frequency of PSA screening among men due for PSA testing,stratified by PSA testing use in the previous 2 years,and clustered by ordering ***:Throughout the study period,PSA testing use was consistently higher for men with previous screening than for men without previous *** men without previous screening,there was a decline in testing that was most pronounced in *** with 2009,the cor-responding odds ratios were 0.98[95%confidence interval(CI)(0.96-1.00)]in 2010,0.94[95%CI(0.92-0.95)]in 2011,and 0.66[95%CI(0.65-0.68)]in *** contrast,for men with previous screening,PSA testing frequency was stable from 2009 to 2011,and declined to a lesser extent in 2012[odds ratio 0.80,95%CI(0.79-0.81)].Conclusion:Receipt of PSA testing is highly dependent on whether an individual was tested in the recent *** previously unscreened men,the largest decrease occurred in 2012,which may reflect in part the publication of US Preventive Services Task Force guidelines,but there was much less impact among men already being screened.

关键词： Prostate-specific antigen medicare mass screening clinical practice patterns

The double helium-white dwarf channel for the formation of Am CVn binaries

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Research in Astronomy and Astrophysics 2018年第1期18卷 101-112页

作者： Xian-Fei Zhang Jin-Zhong Liu C.simon Jeffery Philip D.Hall Shao-Lan Bi Department of Astronomy Beijing Normal University Xinjiang Astronomical Observatory Chinese Academy of Sciences Armagh Observatory and Planetarium College Hill School of Physics Trinity College Dublin

most close double helium white dwarfs will merge within a Hubble time due to orbital decay by gravitational wave ***,a significant fraction with low mass ratios will survive for a long time as a consequence of stable mass *** stable mass transfer between two helium white dwarfs（He WDs） provides one channel for the production of Am CVn binary *** previous calculations of double He WD progenitors,the accreting He WD was treated as a point *** have computed the evolution of 16 double He WD models in order to investigate the consequences of treating the evolution of both components in *** find that the boundary between binaries having stable and unstable mass transfer is slightly modified by this *** comparing with observed periods and mass ratios,we redetermine masses of eight known Am CVn stars by our double He WDs channel,*** Cnc,Am CVn,V406 Hya,J0926,J1240,GP Com,Gaia14 aae and V396 *** propose that central spikes in the triple-peaked emission spectra of J1240,GP Com and V396 Hya and the surface abundance ratios of N/C/O in GP Com can be explained by the stable double He WD *** mass estimates derived from our calculations are used to discuss the predicted gravitational wave signal in the context of the Laser Interferometer Space Antenna（LISA） project.

关键词： stars:peculiar(helium) stars:white dwarfs binaries:close gravitational waves

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Essential oil of Curcuma wenyujin induces apoptosis in human hepatoma cells

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World Journal of Gastroenterology 2008年第27期14卷 4309-4318页

作者： YU Xiao Feng-Qing Yang Shao-Ping Li Guang Hu simon ming-Yuen Lee Yi-Tao Wang State Drug Clinical Trial Agency Science & Technology Department Sichuan Provincial People's Hospital Sichuan Academy of Medical Science Chengdu 610072 Sichuan Province China Institute of Chinese medical Sciences University of Macao Av. Padre Tomas Pereira S.J. Taipa Macao China Institute of Chinese medicine the Chinese University of Hong Kong Hong Kong China

AIm: To investigate the effects of the essential oil of Curcuma wenyujin (CWO) on growth inhibition and on the induction of apoptosis in human HepG2 cancer cells. mETHODS: The cytotoxic effect of drugs on HepG2 cells was measured by 3-(4,5-dimethylthiazol-2- yl)-2,5-diphenyltetra-zolium bromide (mTT) assay. DNA fragmentation was visualized by agarose gel electrophoresis. Cell cycle and mitochondrial transmembrane potential (△Ψm) were determined by flow cytometry (FCm). Cytochrome C immunostaining was evaluated by fluorescence microscopy. Caspase-3 enzymatic activity was assayed by the cleavage of Ac-DEVD-R110. Cleaved PARP and active caspase-3 protein levels were measured by FCm using BD? CBA Human Apoptosis Kit. RESULTS: Treatment with CWO inhibited the growth of HepG2 cells in a dose-dependent manner, and the IC50 of CWO was approximately 70 μg/mL. CWO was found to inhibit the growth of HepG2 cells by inducing a cell cycle arrest at S/G2. DNA fragmentation was evidentlyobserved at 70 μg/mL after 72 h of treatment. During the process, cytosolic HepG2 cytochrome C staining showed a markedly stronger green fluorescence than in control cells in a dose-dependent fashion, and CWO also caused mitochondrial transmembrane depolarization. Furthermore, the results clearly demonstrated that both, activity of caspase-3 enzyme and protein levels of cleaved PARP, significantly increased in a dose- dependent manner after treatment with CWO. CONCLUSION: CWO exhibits an antiproliferative effect in HepG2 cells by inducing apoptosis. This growth inhibition is associated with cell cycle arrest, cytochrome C translocation, caspase 3 activation, Poly- ADP-ribose polymerase (PARP) degradation, and loss of mitochondrial membrane potential. This process involves a mitochondria-caspase dependent apoptosis pathway. As apoptosis is an important anti-cancer therapeutic target, these results suggest a potential of CWO as a chemotherapeutic agent.

关键词： Essential oil Curcuma wenyujin, Apoptosis HepG2 Caspase-3 mitochondrial Cytochrome C Cleaved Poly-ADP-ribose polymerase

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2004家禽技术发展趋势

中国家禽 2004年第17期26卷 51-52页

作者：刘向萍 simon m.Shane

过去连续三年国际家禽展览会所反映出的家禽行业的整合和结构的变化,使人们更加关注生产的高效率和成本的降低,如何降低成本、预防疾病和高效使用劳动力是目前需要思考的问题,2004年国际家禽展览会于2004年1月28日～30日在美国举行,会... 详细信息

过去连续三年国际家禽展览会所反映出的家禽行业的整合和结构的变化,使人们更加关注生产的高效率和成本的降低,如何降低成本、预防疾病和高效使用劳动力是目前需要思考的问题,2004年国际家禽展览会于2004年1月28日～30日在美国举行,会议呈现出的家禽先进技术发展趋势有四个方面:蛋内注射系统、自动捕鸡技术、抗生素饲料添加剂的替代物和提高消化率的酶。

关键词： 2004年家禽养殖技术蛋内注射系统自动捕鸡技术抗生素饲料添加剂

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机器人操作器姿态性能的自动测量

机器人 1990年第4期12卷 29-35页

作者：叶宁 m.Betemps T.P.simon A.Jutart 中国科学院紫金山天文台法国里昂国立应用科学学院工业自动化实验室

本文介绍了作者在里昂国立应用科学学院工业自动化实验室发展的一个无机械接触的姿态性能自动测量系统.该系统由测量头、靶子和数据采集、处理子系统构成.测量头是一铅质直角三面体.其上装有六个感应式位移传感器;靶子是一钢质直角三面... 详细信息

本文介绍了作者在里昂国立应用科学学院工业自动化实验室发展的一个无机械接触的姿态性能自动测量系统.该系统由测量头、靶子和数据采集、处理子系统构成.测量头是一铅质直角三面体.其上装有六个感应式位移传感器;靶子是一钢质直角三面体.与被测机器人相联接;靶子相对测量头的姿态可根据传感器给出的距离数据算出,一台微计算机管理着数据的自动采集处理以及与机器人控制器之间的通信与协调动作,对两台机器人进行的实际测量应用.已展示了一些有意义的结果;同时也表明,该测量系统可以在工业环境中可靠和方便地用于多种工业机器人的姿态重复性和动态性能的测试,并且具有造价低,适应性强和自动化程度高等特点.

关键词：机器人操作器姿态性能自动测量

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