检索结果-南通市图书馆

Antioxidant antileishmanial cytotoxic and antimicrobial activities of a local plant Myrtus nivellei from Algeria Sahara

引用

Asian Pacific Journal of Tropical Biomedicine 2017年第8期7卷 702-707页

作者： Farah Ramdane Rym Essid Nadia Fares Dahmane El Ouassis Sana Aziz Mahfoud hadj Mahammed mohamed didi ould hadj Ferid Limam Biogeochemistry Laboratory in Desert Environments Kasdi Merbah University Faculty of Natural and Life Sciences El Oued University Laboratory of Bioactive Substances Biotechnology Center of Borj-Cedria Technopole National Institute of Forest Research Protection Laboratory of Ecosystem in Arid and Semi Arid Zone Kasdi Merbah University

To study the phytochemical constituents and in vitro biological activities of hydromethanolic extract and fractions from Algerian Sahara Myrtus nivellei (M. nivellei) collected in Hoggar region and to identify the active fraction that can act as an alternative of commonly used antibiotics and as antileishmanial or antioxidant *** screening of M. nivellei aerial parts was realised according to the literature. Extract was firstly prepared by using aqueous methanol then fractionated with ethyl acetate and butanol solvents. Total phenolics, tannis and flavonoids, of the hydromethanolic extract and their fractions were determined by Folin-Ciocalteu method as gallic acid equivalents and by aluminium chloride as rutin equivalent respectively. Extract and fractions were tested for their antimicrobial and antiparasital activities against standard bacteria using agar diffusion method and two kinds of leishmania visceral and cutaneous. The antioxidant activities were realized using phosphomolybdenum, FRAP and DPPH *** phytochemical screening exhibited the presence of flavonoids, tannins, saponins, and alkaloids. The experimental results showed that plant extract and fractions were high in phenolic compounds and exhibited an important role as antioxidant, antimicrobial and had a moderate antileishmanial *** observations lead us toward more studies in this field, so that we can get more benefits from our local Algerian medicinal plants.

关键词： Phenolic compounds Flavonoids Antioxidant activity Antimicrobial activity Antileishmanial activity Myrtus nivellei

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Application of Remote Sensing and GIS in Mineral Alteration Mapping and Lineament Extraction Case of Oudiane Elkharoub (Requibat Shield, Northern of Mauritania)

引用

Open Journal of Geology 2024年第9期14卷 823-854页

作者： ould Mahmoud Hdeid Yousra Morsli mohamed Raji Zouhir Baroudi Malika Adjour Khaled Cheikh Nebagha Zein El Arby Vetah mohamed El Moktar Isselmou Brahim Vall Department of Geology Faculty of Sciences Ben Msik Hassan II University Casablanca Morocco Department of Geology Faculty of Sciences and Technology University of Nouakchott Al Asriya Nouakchott Mauritania National Agency for Geological Research and Mining Heritage Nouakchott Mauritania

The integration of remotely sensed data allowed the successful characterization of the mineral alteration zones of the Oudiane Elkharoub area in the Northeastern part of Reguibat Shield using image transformation techniques. As both chemical and geochemical analyses showed significant Au, Ag, Cu, Pb, Mn, Cr, Ni, Th and Y anomalies, it’s very interesting to apply the remote sensing and GIS in mineral resources mapping. The remote sensing is a direct adjunct to the field, lithologic and structural mapping, and more recently, GIS has played an important role in the study of mineralization areas. The integration of several evidential maps highlighted the plausible areas with high concentrations of chlorite, epidote, kaolinite, calcite, alunite, hematite, illite and sulfur among other key mineral alterations that reflect the intensity of hydrothermal effects and the probable sites of ore bodies. The methodological approach integrates geological information acquired from Aster and Landsat 8 OLI/TIRS (Operational Land Imager/Thermal InfraRed Sensor) images and a multi-criteria GIS analysis. The superimposition of various lineament and hydrothermal alteration maps and the consideration of precious and base metal indicators allowed the zoning of sites likely to contain mineral concentrations. Remote sensing becomes an important tool for locating mineral deposits in its own right, when the primary and secondary processes of mineralization result in the formation of spectral anomalies. Reconnaissance lithological mapping is usually the first step of mineral resource mapping. This is complimented with structural mapping, as mineral deposits usually occur along or adjacent to geologic structures, and alteration mapping, as mineral deposits are commonly associated with hydrothermal alteration of the surrounding rocks. Ground truthing and laboratory studies including XRD analysis were utilized to verify the results.

关键词： Remote Sensing GIS ASTER Landsat 8 (OLI/TIRS) Structure Mineralization Alteration Mineral Lineament Reguibat Shield Oudiane Elkharoub

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Toxicology,biosynthesis,bio-control of aflatoxin and new methods of detection

引用

Asian Pacific Journal of Tropical Biomedicine 2016年第9期6卷 808-814页

作者： mohamed Amine Gacem Aminata ould El hadj-Khelil Laboratory of Protection of Ecosystems in Arid and Semi-Arid Area University of Kasdi Merbah Department of Biology Faculty of ScienceUniversity of Amar Tlidji

Mycotoxins and their derivatives since their discoveries and until the present time are behind unspecified economic and medical *** are classified according to their physical–chemical and toxicological characters in the most dangerous row of the *** aflatoxins are in part responsible,of irreversible medical disasters that are not easily manageable such as cancer of the liver and kidneys,and in the other part,of losses in the stored cereal *** on these crucial findings,monitoring of this toxin became imperative in post-harvest food products,during storage,during transformation chain and even during the long phases of *** of this toxin is delivered by detection methods using very advanced technologies to respond in the shortest possible *** addition,the knowledge of factors supporting the biosynthesis of aflatoxins such as the temperature,moisture content,concentration of nitrogen and carbon,and the molecules responsible for the genetic control of the synthesis will be reflected later in the choice of bio-control *** control is currently based on new strategies using the bioactives substances of the plants,the lactic bacteria and some strains of actinomycetes that have good inhibiting activity against aflatoxins with fewer side effects on *** the other hand,this brief review summarizes the results of new studies demonstrating the toxicity of the toxin,new detection methods and bio-control.

关键词： Mycotoxins Aflatoxins Cancer Biosynthesis Bio-controls Detection methods

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mixed sensitivity H_∞ control for LTI systems with varying time delays

引用

Journal of Systems Engineering and Electronics 2018年第3期29卷 611-617页

作者： ould mohamed mohamed vall College of Computer and Information Sciences Al Jouf University

Designing a robust controller for a system with timevarying delays poses a major challenge. In this paper, we propose a method based on mixed sensitivity H∞ for the control of linear time invariant（LTI） systems with varying time delays. The time delay is assumed bounded and the upper bound is known. In the technique we propose, the delay affecting the plant to be controlled is treated as an unmodeled uncertainty（in form of multiplicative uncertainty）. That uncertainty is approximated and then an H∞based controller, for the plant represented by the multiplicative uncertainty and the nominal model, is calculated. The obtained H∞controller is used to control the LTI systems with varying time delays. Simulation examples are given to illustrate the effectiveness of the proposed method.

关键词： linear time invariant(LTI) systems mixed sensitivity H∞ varying time delay unmodeled uncertainty H∞ control

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

ON SINGULAR EQUATIONS INVOLVING FRACTIONAL LAPLACIAN

引用

Acta Mathematica Scientia 2020年第5期40卷 1289-1315页

作者： Ahmed YOUSSFI Ghoulam ould mohamed MAHMOUD National School of Applied Sciences Sidi mohamed Ben Abdellah University-Fez Laboratory of Mathematical Analysis and Applications My Abdellah Avenue Road ImouzerP.O.Box 72 Fes-Principale30000FezMorocco National School of Applied Sciences Sidi mohamed Ben Abdellah University-Fez My Abdellah Avenue Road ImouzerP.0.Box 72 Fes-Principale30000FezMorocco

We study the existence and the regularity of solutions for a class of nonlocal equations involving the fractional Laplacian operator with singular nonlinearity and Radon measure data.

关键词： fractional Laplacian singular elliptic equations measure data

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Assessment of CareStart G6PD rapid diagnostic test and CareStart G6PD biosensor in Mauritania

引用

Infectious Diseases of Poverty 2021年第4期10卷 33-45页

作者： Oum Kelthoum Mamadou Djigo Yacoub ould Khalef mohamed Salem ould Ahmedou Salem Nicolas Gomez Leonardo Basco Sebastien Briolant Ali ould mohamed Salem Boukhary Unite de Recherche"Genomes et Milieux"(Jeune Equipe Associee a I'lnstitut de Recherche pour le Developpement) Faculte des Sciences et lechniquesUniversite de Nouakchott Al-AasriyaNouakchottMauritania Service de Pediatrie Centre Hospitalier Mere et EnfantNouakchottMauritania IHU Mediterrande InfectionMarseilleFrance Aix Marseille Univ IRDAP-HMSSAVITROMEMarseilleFrance Unite de Parasitologie Entomologie Departement de Microbiologie et Maladies InfectieusesInstitut de Recherche Biomedicale des Armees(IRBA)MarseilleFrance

Background::The elimination of Plasmodium vivax malaria requires 8-aminoquinolines,which are contraindicated in patients with glucose-6-phosphate dehydrogenase(G6PD)deficiency due to the risk of acute haemolytic *** point-of-care devices have been developed to detect G6PD *** objective of the present study was to evaluate the performance of two of these devices against G6PD genotypes in ***::Outpatients were screened for G6PD deficiency using CareStart?rapid diagnostic test(RDT)and CareStart?G6PD biosensor in Nouakchott,Mauritania,in ***-type and Mediterranean-type G6PD genotypes commonly observed in Africa were determined by polymerase chain reaction-restriction fragment length polymorphism and *** variables were compared using Fisher’s exact ***::Of 323 patients(74 males and 249 females),5 males and 2 homozygous females had the African-type A-genotype:A-(202)in 3 males and 2 females and G6PD A-(968)in 2 *** heterozygous females,13 carried G6PD A-(202),12 G6PD A-(968),and 3 G6PD A-(542)*** had the Mediterranean-type G6PD *** had a positive G6PD RDT result,including all 7 hemizygous males and homozygous females with A-or A-A-(0.12 to 2.34 IU/g haemoglobin,according to G6PD biosensor),but RDT performed poorly(sensitivity,11.1%at the cutoff level of<30%)and yielded many false negative ***-seven(50.0%)males and 141(56.6%)females were *** adjusted median values of G6PD activity were 5.72 and 5.34 IU/g haemoglobin in non-anaemic males(n=35)and non-anaemic males and females(n=130)with normal G6PD genotypes using G6PD biosensor,*** on the adjusted median of 5.34 IU/g haemoglobin,the performance of G6PD biosensor against genotyping was as follows:at 30%cut-off,the sensitivity and specificity were 85.7%and 91.7%,respectively,and at 80%cut-off,the sensitivity was 100%while the specificity was 64.9%.Conclusions::Although this pilot study

关键词： Glucose-6-phosphate dehydrogenase Malaria Plasmodium vivax Primaquine Tafenoquine

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

PLANNED LEAD TIME OPTIMIZATION IN MATERIAL REQUIREMENT PLANNING ENVIRONMENT FOR MULTILEVEL PRODUCTION SYSTEMS

引用

Journal of Systems Science and Systems Engineering 2008年第2期17卷 132-155页

作者： Faicel HNAIEN Alexandre DOLGUI mohamed-Aly ould LOULY Industrial Engineering and Computer Science Centre(G2I)Ecole des Mines de St Etienne 158cours Fauriel42023 Saint EtienneFrance King Saud University College of Engineering-Industrial Engineering Department P.O.B 800 Riyadh 11421Kingdom of Saudi Arabia

This paper deals with the problem of planned lead time calculation in a Material Requirement Planning （MRP） environment under stochastic lead times. The objective is to minimize the sum of holding and backlogging costs. The proposed approach is based on discrete time inventory control where the decision variables are integer. Two types of systems are considered： multi-level serial-production and assembly systems. For the serial production systems （one type of component at each level）, a mathematical model is suggested. Then, it is proven that this model is equivalent to the well known discrete Newsboy Model. This directly provides the optimal values for the planned lead times. For multilevel assembly systems, a dedicated model is proposed and some properties of the decision variables and objective function are proven. These properties are used to calculate lower and upper limits on the decision variables and lower and upper bounds on the objective function. The obtained limits and bounds open the possibility to develop an efficient optimization algorithm using, for example, a Branch and Bound approach. The paper presents the proposed models in detail with corresponding proofs and se＇~eral numerical examples. Some advantages of the suggested models and perspectives of this research are discussed.

关键词： Multilevel assembly and production control model planned lead time optimization systems MRP random lead times discrete inventory

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An Analytical Model for Torus Networks in the Presence of Batch Message Arrivals with Hot-spot Destinations

引用

International Journal of Automation and computing 2009年第1期6卷 38-47页

作者： Yulei Wu Geyong Min mohamed ould-Khaoua Hao Yin Department of Computing School of Informatics University of Bradford Bradford BD7 1DP UK Department of Computing Science University of Glasgow Glasgow G12 8RZ UK Department of Computer Science Tsinghua University Beijing 100084 PRC

Interconnection networks are hardware fabrics supporting communications between individual processors in multi- computers. The low-dimensional k-ary n-cubes （or torus） with adaptive wormhole switching have attracted significant research efforts to construct high-performance interconnection networks in contemporary multi-computers. The arrival process and destination distribution of messages have great effects on network performance. With the aim of capturing the characteristics of the realistic traffic pattern and obtaining a deep understanding of the performance behaviour of interconneetion networks, this paper presents an analytical model to investigate the message latency in adaptive-routed wormhole-switched torus networks where there exists hot-spot nodes and the message arrivals follow a batch arrival process. Each generated message has a given probability to be directed to the hot-spot node. The average degree of virtual channel multiplexing is computed by the GE/G/1/V queueing system with finite buffer capacity. We compare analytical results of message latency with those obtained through the simulation experiments in order to validate the accuracy of the derived model.

关键词： Multi-computers interconnection networks non-uniform traffic generalised exponential distribution GE/G/1/V.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Wave Kernels with Bi-Inverse Square Potentials on Euclidean Plane

引用

Journal of Partial Differential Equations 2015年第1期28卷 9-22页

作者： MOUSTAPHA mohamed Vall ould Universitd des Sciences de Technologie et de la Medecine (USTM) Faculte des Sciences et Techniques. Unite de recherche: Analyse EDP et Moddlisation Facult des Sciences et Techniques Universit des Sciences de Technologie et de la medecine Nouakchott BP: 5026 Mauritanie.

The Cauchy problem for the wave equation with bi-inverse square potential on Euclidean plane is solved in terms of the two variables Appell F2 hypergeometric functions. Our principal tools are the Hankel transforms an... 详细信息

关键词： Inverse square potential wave equation Hankel transform Bessl functions F2- Appell hypergeometric function.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

E-Passport and Building Online Passport Service System

E-Passport and Building Online Passport Service System

引用

作者： mohamed Lemine ould Nomane（诺曼）武汉理工大学

学位级别：硕士

随着IT技术的发展,生物识别技术已经成为一个研究的热点领域。各国政府都纷纷资助生物识别技术方面的研究,该领域方面的学术会议吸引了政府和业界众多的参与者,理论研究的成果正快速地转换为商业产品。在某种意义上讲,生物识别技术属于...

随着IT技术的发展,生物识别技术已经成为一个研究的热点领域。各国政府都纷纷资助生物识别技术方面的研究,该领域方面的学术会议吸引了政府和业界众多的参与者,理论研究的成果正快速地转换为商业产品。在某种意义上讲,生物识别技术属于理论知识前沿范畴,可以表达复杂的设计问题,因此生物识别技术和RFID技术尤为重要。在此基础上,论文研究电子护照和护照服务系统的构建,电子护照记载了公民的特征信息,是政府及各国海关识别公民身份的重要依据。对电子护照的相关技术以及护照相关信息的管理展开研究,具有较为重要的研究和应用价值。论文主要工作包含两部分：(1)对于包含生物识别和RFID芯片的公民电子护照的论证;(2)使用UML和DOTNET设计并实现了了电子护照的在线服务系统。第一部分首先介绍了生物识别技术和RFID相关技术。概述了几种不同的生物识别技术：虹膜识别、手型识别、指纹识别、视网膜识别和面部识别等技术,综述了PKI和数字签名技术,而后介绍了RFID标签、RFID结构等相关技术。第二部分探讨了如何利用C#、***和UML开发一个在线的护照服务系统,讨论了护照在线服务系统的设计,采用用例图和类图分别描述需求和功能设计,应用概念数据模型和物理数据模型描述数据库设计。

关键词：

来源：

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：