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Pegylated interferon α/ribavirin therapy enhances bone mineral density in children with chronic genotype 4 HCV infection

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World Journal of Pediatrics 2017年第4期13卷 346-352页

作者： Ahmed Megahed Nanees Salem Abeer Fathy Tarik Barakat Mona Abd El latif Alsayed Suzy Abd El Mabood Khaled R Zalata Ahmed F Abdalla Pediatric Gastroenterology and Hepatology Unit Mansoura University Children's HospitalFaculty of MedicineMansoura UniversityEgypt Pediatric Endocrinology Unit Mansoura University Children's HospitalFaculty of MedicineMansoura UniversityEgypt Pediatric Hematology&Oncology Unit Mansoura University Children's HospitalFaculty of MedicineMansoura UniversityEgypt Pathology Department Faculty of MedicineMansoura UniversityEgypt

Background:The impact of chronic hepatitis C (CHC) on bone mineral density (BMD) has been well studied in adults with a relative paucity of data in children,especially concerning effect of treatment with pegylated interferon (PEG-IFN) plus ribavirin (RV).In the current work,we assessed prospectively changes in BMD in children with CHC before,during,and after ***:Forty-six consecutive children with noncirrhotic genotype 4 CHC were subjected to dual-energy X-ray absorptiometry at baseline,24 weeks,48 weeks of therapy and 24 weeks after ***,bone mineral content (BMC),and Z score of lumbar spine (L2-L4) were *** pubertal stage,viral load,liver function tests,serum calcium,phosphorus,alkaline phosphatase,parathyroid hormone,and liver histopathology were assessed in all included ***:Thirty (65.2%) patients had normal BMD,10 (21.7%) were at risk for low BMD,and 6 (13.1%) had low BMD for chronological *** with low BMD were significantly older (P=0.001),with higher frequency of delayed puberty than other groups (P=0.002).Baseline densitometric parameters (BMD & BMC) were significantly positively correlated with patients' age,weight,height,body mass index and hemoglobin level;while they were insignificantly correlated with basal viral load,histopathology activity index and fibrosis *** parameters improved significantly on PEG-IFN plus RV treatment,this improvement was found to be sustainable 24 weeks after ***:Low BMD is detectable in a proportion of CHC *** therapy leads to a sustainable increase in BMD.

关键词： bone mineral density chronic hepatitis C pegylated interferon ribavirin

水力脉动压裂过程中注入参数对裂缝扩展的影响规律研究

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水力脉动压裂过程中注入参数对裂缝扩展的影响规律研究

作者： Abdoul latif Assoumane 中国石油大学(华东)

学位级别：硕士

水力脉动压裂技术在改善煤层气驱的效果方面取得显著成效。近年来,该技术逐渐应用于裂缝性低渗透油藏中的储层改造中,但由于其机理的复杂性,大都借鉴在煤层脉动压裂中的认识,对该技术在油层的压裂机理研究尚不充分,其应用仍面临很多挑... 详细信息

水力脉动压裂技术在改善煤层气驱的效果方面取得显著成效。近年来,该技术逐渐应用于裂缝性低渗透油藏中的储层改造中,但由于其机理的复杂性,大都借鉴在煤层脉动压裂中的认识,对该技术在油层的压裂机理研究尚不充分,其应用仍面临很多挑战。尤其是存在天然裂缝发育的低渗油藏,更需要明确脉冲压裂裂缝与天然裂缝之间的交互关系。基于此,本文主要研究水力脉动压裂对裂长和缝宽影响规律,进一步探究脉冲压裂产生的主裂缝与天然裂缝之间的交互关系。因此,本文借助Abaqus软件进行数值模拟,利用牵引力分离定律和内聚力单元法来模拟裂缝的产生和扩展;使用python脚本编程模拟了脉冲压裂裂缝与天然裂缝之间的交互。在构建的模拟程序的基础上,分别研究了脉动幅度和频率,天然裂缝倾斜角,原始地应力差异,天然裂缝抗张强度等因素对复杂裂缝扩展的影响。结果表明:水力脉动频率对单裂缝的起裂压力,缝宽,起裂的天然裂缝数量有较大影响。对于单裂缝而言,随着水力脉动频率的增加缝长会略微增大,但缝宽减小,其岩石的破裂压力也会稍微减小,对于单裂纹传播,结果表明裂缝宽度和长度随峰值振幅的增加而成比例增加。对于存在多裂缝的复杂裂缝情况,存在裂缝的数量越多则越复杂,设定了0.5 MPa,1.5 MPa和2 MPa的峰值振幅的影响,表明其峰值振幅的增加降低了缝网的复杂性。对于两个裂缝相交模式,模拟了两裂缝交叉角度为75°,60°,45°和30°的效果。可知即使交叉角度小于60°,水力脉冲压力也能促进天然裂缝的进一步延伸扩展,运用常规的水力压裂方法随其进行计算是不适用的;进一步通过模拟得到交叉角度小于60度时,天然裂缝易起裂且缝长和缝宽较大。关于地应力对裂缝起裂扩展的影响,设定0 MPa,0.5MPa和3 MPa的地应力进行模拟发现水力脉动裂缝的缝宽随地应力的增加而增加,天然裂缝的缝宽随地应力的增加而减小。设定1 MPa,2 MPa和3 MPa的天然裂缝抗压强度进行模拟,抗压强度越小则水力脉动压裂更易使裂缝起裂与天然裂缝相接。对于脉动速率的影响,一方面可以降低岩石的抗压强度,另一方面对地应力的分布具有较大影响,脉动速率的增加无论裂缝的角度方向如何,都可能会导致更多的裂缝产生。

关键词：水力脉动压裂天然裂缝复杂缝网扩展 ABAQUS有限元模拟

寒武纪芙蓉统均一石沉积组构及环境特征——以河北涞源长山组为例

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沉积学报 2020年第1期38卷 76-90页

作者：肖恩照王皓覃英伦 Khalid latif Muhammad Riaz 中国地质大学(北京)地球科学与资源学院北京100083 中国地质调查局油气资源调查中心北京100083 白沙瓦大学国家地质研究中心巴基斯坦25130

均一石以隐晶质岩性、无纹层与凝块结构发育为特征,与叠层石、凝块石、树形石并列为典型的微生物岩。然而,由于均一石在1995年命名以来很少在地层记录中得到识别和描述,并且缺乏现代实例的类比物,使得关于均一石的报道极具研究价值。为... 详细信息

均一石以隐晶质岩性、无纹层与凝块结构发育为特征,与叠层石、凝块石、树形石并列为典型的微生物岩。然而,由于均一石在1995年命名以来很少在地层记录中得到识别和描述,并且缺乏现代实例的类比物,使得关于均一石的报道极具研究价值。为研究华北地台寒武系均一石沉积组构与形成环境特征,系统性地针对河北涞源祁家峪剖面芙蓉统长山组均一石生物丘进行研究。芙蓉统长山组从下部陆棚相钙质泥岩向上变浅至浅缓坡相厚层块状泥晶灰岩,组成了一个淹没不整合型三级层序。三级层序顶部的浅缓坡相厚层块状泥晶灰岩层,代表强迫型海退过程沉积,其内部发育一系列米级均一石生物丘。研究结果表明,这些生物丘主体为致密泥晶及少量微量晶组成,其中可见到附枝菌(Epiphyton)、葛万菌(Girvanella)、肾形菌(Renalcis)等钙化微生物化石。这些钙化微生物(蓝细菌)化石的出现,代表了显生宙第一幕蓝细菌钙化作用事件的证据,同时间接的说明均一石生物丘形成于蓝细菌主导的微生物席的钙化作用过程之中。同时,生物丘内还局部集中发育底栖鲕粒与草莓状黄铁矿颗粒,表明了生物丘形成过程中复杂的微生物沉积作用机制。因此,河北涞源长山组顶部的均一石生物丘,尽管泥晶和微亮晶是其基本构成,但是各种钙化蓝细菌化石以及底栖鲕粒与草莓状黄铁矿颗粒的局部出现表明了在蓝细菌主导的微生物席中复杂的微生物活动信号,成为了解生物丘形成机制、显生宙第一幕蓝细菌钙化作用事件的典型实例。

关键词：均一石生物丘钙化微生物底栖鲕粒草莓状黄铁矿寒武系芙蓉统

Impact of Climatic Parameters on the Performance of Solar Photovoltaic (PV) Module in Niamey

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Smart Grid and Renewable Energy 2017年第12期8卷 379-393页

作者： Abdou latif Bonkaney Saidou Madougou Rabani Adamou Master Research Program Climate Change and Energy UAM Niamey Niger Ecole Normale Superieure UAM Niamey Niger Departments of Chemistry UAM Niamey Niger

The sensitivity of mono-crystalline solar PV module towards dust accumulation, ambient temperature, relative humidity, and cloud cover is investigated from May to August 2015 for Niamey’s environment. Two solar modules with the same characteristics have been used to carry out the impacts of the dust on the solar PV module. One of the modules is being cleaned every morning and the second one was used for monitoring the effect of dust accumulation onto the surface of the unclean module for May and June. The ambient temperature around the solar PV module was recorded at the same time with the output voltage and the output current to assess the impacts of ambient temperature on the PV conversion efficiency. In addition to these field test measurements, the solar radiation data measured in National Center of Solar Energy (CNES) of Niamey were also used. Also the relative humidity for the study area data obtained NASA power agro-climatology website was used. Results show that the dust accumulation has the greatest impact on the performance of the PV module followed by temperature, relative humidity and cloud cover. Exposing the module in 23 days has reduced the energy output by 15.29%. The power output and the conversion efficiency of the PV module have dropped by 2.6% and 0.49% respectively. The relative humidity also has reduced the energy output by 4.3 Wh/m2/day.

关键词： Mono-Crystalline Solar PV Dust Accumulation Ambient Temperature Conversion Efficiency Daily Energy Output

微生物碳酸盐岩的成因、分类以及问题与展望——来自华北地台寒武系微生物碳酸盐岩研究的启示

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地球科学进展 2018年第10期33卷 1005-1023页

作者：王龙 Khalid latif Muhammad Riaz 刘晓晔中国地质大学(北京)地球科学与资源学院北京100083 National Centre of Excellence in Geology University of Peshawar

微生物碳酸盐岩以其漫长的地史分布、多样的产出环境、复杂的沉积构成和与微生物活动密切相关的特性而成为沉积学研究的焦点,同时也是沉积学研究的难点,被誉为"最难研究的沉积岩之一"。其研究的中心主要是钙化微生物席和微生物膜及其地... 详细信息

微生物碳酸盐岩以其漫长的地史分布、多样的产出环境、复杂的沉积构成和与微生物活动密切相关的特性而成为沉积学研究的焦点,同时也是沉积学研究的难点,被誉为"最难研究的沉积岩之一"。其研究的中心主要是钙化微生物席和微生物膜及其地质记录,即石化/成岩作用的产物。从成因着手,系统总结和梳理了2个类型的微生物群落,较薄的生物膜和较厚的微生物席,经过生物/有机矿化作用和石化/成岩作用形成微生物碳酸盐岩的过程。提出除微生物群落自身的复杂性和沉积过程的复杂性之外,多重状生物膜是导致微生物碳酸盐岩多样性的另外一个重要原因。以中国华北地台寒武系微生物碳酸盐岩的研究为基础,梳理了不同类型的微生物碳酸盐岩的沉积特征和分类依据。认为微生物碳酸盐岩应该置于Embry和Kloven描述的黏结岩类下,根据宏观组构可进一步分为叠层石、凝块石、核形石、层纹石和均一石5类,树形石不易独立成类而应归于凝块石。微生物碳酸盐岩为整个地质历史时期与微生物活动相关的生物/有机矿化作用过程研究提供了有用信息,不但是了解地球表层环境演变的一个重要窗口,而且还形成和储集了较大规模的油气,具有重要的科学意义和经济价值。

关键词：微生物碳酸盐岩微生物席华北地台寒武系成因

Lane Change Decision Analysis on Freeways by LightGBM and SHAP

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Lane Change Decision Analysis on Freeways by LightGBM and SH...

作者： Muhammad Owais latif（欧瓦）东南大学

学位级别：硕士

Vehicle lane change maneuvering could have a substantial influence on traffic flow and safety as a result of their interfering influence in the surrounding *** interference effect of lane changing could be more pronounced when vehicles maneuvers horizontally and change the white road *** freeway crashes occur in the vicinity of interchange diverging and merging areas,especially in speed-change *** vehicles maneuvers in different lanes during a lane *** alteration in maneuvering is due to the influence of surrounding vehicles which impose on the lane change *** study is exploring the factors attribution in making lane change prediction through Shapley Additive ***,in order to predict the maneuvering in terms of lane changes on the urban arterial,accurate machine learning modelling is *** developing machine learning models,real data are used to set up explanatory variables and to the evaluation of *** study will help traffic engineers and manager to a better understanding of the how various lane change maneuvering takes place and the impact of lane change on traffic operation and *** results showed that the trained logistic regression model achieved an accuracy of 70%,while the accuracy of Light GBM classifier with tunned hyper-parameters was 73.4% in predicting the lane changing instant and the surrounding traffic characteristics on lane change *** under the ROC was pretty *** the SHAP value analysis,it was found that the vehicle dimensions(length,Width)and velocity shows a significant impact on lane changing decision,and also lane changing with insufficient space headway gap makes the collision risk higher and driver engage in lane changing *** larger space headway lane change urgency *** same behavior has been found with the following gap in current lane and gap acceptance in the target *** the case of preceding and following vehicle speed in the

关键词： Vehicle Maneuvering Lane Change Traffic Safety operation Explanatory variables Surrounding vehicle characteristics Machine Learning Logistic Regression Light GBM Classifier SHAP values

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基于本体的可视化股票信息系统

基于本体的可视化股票信息系统

作者： Khamis Abdul-latif Khamis 武汉理工大学

学位级别：硕士

随着互联网和经济的快速发展,在互联网中存在越来越多不同类型的股票信息,这些股票信息具有高维度、信息量大、易变等特点,并经常给一般用户带来困惑。因此,用户需要好的信息表示方式以获取自己需要的信息和友好人机交互去访问网络信息... 详细信息

随着互联网和经济的快速发展,在互联网中存在越来越多不同类型的股票信息,这些股票信息具有高维度、信息量大、易变等特点,并经常给一般用户带来困惑。因此,用户需要好的信息表示方式以获取自己需要的信息和友好人机交互去访问网络信息。本文把本体和可视化技术结合起来,用于解决股票信息的语义与内容呈现。通过构建股票领域本体,构建股票的语义,能够明确地、形式化地描述股票信息及其股票信息的相互关系,并提供股票信息综合的本体驱动;可视化是利用计算机图形学和图像处理技术,将数据转换成图形或图像在屏幕上显示出来,并进行交互处理的技术,用它可以为用户形象地显示股票数据和股票信息。本文的研究对象是雅虎财经网站(http://***/finance),该网站提供了足够的信息满足本研究。雅虎公司提供的股票信息是基于文本模型和表格模型、股票信息分散在网站的不同网页,用户很难根据自己的需求捕捉到适合的股票信息。另外,雅虎网站不允许用户使用股票服务,仅仅依靠股票历史数据和当前数据,一般的用户去很难理解和分析股票信息。本文的主要贡献如下： (1)给出了VSIS的系统分析。本文详细给出了VSIS的需求分析,包括VSIS的顶层用例图及描述、语义ER模型及数据库设计。 (2)给出了可视化的股票信息系统本体的学习模型。利用从yahoo财经站点、股评领域、VSIS需求、领域知识库这4种不同的信息来源,指导对股票信息本体的逐步学习与求精的过程,得到VSIS的顶层本体池。在本体学习过程中,通过斯坦福大学开发的开源软件protege建模来过滤、解释和验证本体的逻辑与正确性;学习过程与验证过程同时进行、相互验证与修改,以确定VSIS顶层本体。然后,再依次确定下层本体。所建立的本体可以使用OWL、RDF、RDF Scheme进行描述。 (3)给出了可视化股票信息系统的本体的形式化定义O=(C, R, A, I),可视化股票信息系统的本体用于描述股票信息的元素(实例、术语、词汇),关系和规则,另外,可视化股票信息系统的本体等同于分类,该分类层次结构及其关系来分析股票信息,利用形式化的四元组从功能与信息层面描述了可视化股票信息系统中的本体。 (4)建立了基于可视化股票信息系统本体的可视化股票信息系统框架,该框架是一个客户/服务器架构,能依据用户的需求进行查询股票信息并显示服务;同时系统提供了数据交易层、非数据交易层、股票信息层和智能信息层四个层次的股票可视化,易于用户理解,并方便与用户的交互。 (5) VSIS的原型系统在Windows操作系统、MATLAB 7.0和SQL Sever中进行开发,系统能根据用户输入的股票代号,为用户提供不同可视化股票信息的呈现,方便用户查找、检索、比较和浏览股票信息。实验结果表明基于本体的可视化股票信息系统既能很好地表示股票信息,又能为用户提供很好的交互,达到了既定的可视化股票信息系统的设计需求。

关键词：股票信息系统本体可视化 web本体语言(OWL) 语义

Morphological and Genetical Variability among Rhizoctonia solani Isolates Causing Sheath Blight Disease of Rice

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Rice science 2016年第1期23卷 42-50页

作者： Zakiah Rahman MONI Md Ansar ALI Md Shahidul ALAM Md Asif RAHMAN Md Rejwan BHUIYAN Md Salim MIAN Khandakar Md IFTEKHARUDDAULA Md Abdul latif Mohammad Ashik Iqbal KHAN Plant Breeding Division Bangladesh Rice Research Institute Director Research Bangladesh Rice Research Institute Department of Botany Rajshahi University Department of Genetics and Plant Breeding Bangabandhu Sheikh Mujibur Rahman Agricultural University Plant Pathology Division Bangladesh Rice Research Institute

Eighteen isolates of Rhizoctonia solani collected from infected rice plants in four different locations of Bangladesh were studied by using morphological characters and molecular markers. Anastomosis study with a reference isolate confirmed that all the isolates belonged to R. solani. Significant variation was observed in sclerotial size, shape and distribution. Un-weighted pair group method with arithmetic mean dendrogram constructed based on the Gower＇s general similarity coefficient showed that these isolates were grouped into four clusters at the 0.68 similarity coefficent according to morphological characters. Cluster I was a major cluster consisting of 13 isolates, while clusters Ⅱ to Ⅳ consisted of 1 or 2 isolates. Analyses by variable number of tandem repeat and amplified fragment length polymorphism markers showed that the isolates were grouped into five and three clusters at a similarity coefficient of 0.64 and 0.69, respectively. Although most of the variability was found between isolates from different regions as expected, significant variation was observed within the isolates collected from similar agro-ecological regions. Our results suggest the presence of different races of R. solani within the same local geographic regions.

关键词： rice Rhizoctonia solani fungal variability molecular marker morphological character

Economic Cost of Community-Based Management of Severe Acute Malnutrition in a Rural District in Ghana

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Health 2014年第10期6卷 886-889页

作者： Abdul-Malik Chantimah Abdul-latif Justice Nonvignon Department of Health Policy Planning & Management School of Public Health University of Ghana Legon Ghana District Health Directorate Ghana Health Service Jasikan Ghana

Background: The community based management of severe acute malnutrition (CMAM) was introduced in Ghana in 2008 to manage cases of severe acute malnutrition (SAM) recorded at the community level. This study estimated the economic cost of the CMAM programme for children under-five in the Agona west municipality of Ghana. Methods: A retrospective cross sectional study that used a cost analysis design was employed to estimate the economic cost of the programme from the societal perspective. Household cost data from caregivers were obtained using a semi-structured questionnaire. That of programme cost data was obtained from document reviews as well as the use of semi-structured questionnaires and subsequent discussions with key personnel of the Ghana Health Service, Food and Nutrition Technical Assistance and UNICEF. One and multi-way sensitivity analyses were conducted to test how sensitive the cost estimates are to certain variations in the cost profiles. Results: The economic household cost of CMAM was estimated as $1905.32 ($47.63 per household) of which 79% was attributed to direct cost while the remaining 21% made up indirect cost. Programme economic cost of CMAM was estimated as $27633.5 (96% recurrent and 4% capital), with refresher training constituting majority of the cost (34%). The constituents of the total economic cost of the programme, estimated as $32214.56 are programme cost (86%), household costs (6%) and community volunteer cost (8%). Therefore, the economic cost of treating one SAM case using the CMAM protocol was estimated as $805.36. Conclusion: Although CMAM has proven to be an effective tool for the management of SAM, its associated costs are quite enormous when coverage levels (geographic) are high yet small number of cases are detected and treated. Therefore, it is prudent to implement several cost saving strategies such as a reduction in the number of days spent on trainings in order to reduce these costs.

关键词： Severe Acute Malnutrition Community-Based Management of Acute Malnutrition Economic Cost Ghana Nutrition Children under Five