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Water conservation in the Arab region: a must for survival

Research in Cold and Arid Regions 2013年第1期5卷 157-164页

作者： Gamal M. Abdo Abdin M. A. salih Abdulmohsen al-Sheikh Civil Engineering Department University of Khartoum Sudan alzamil Group Chair King Saud University Riyadh Saudi Arabia

The Arab region covers an area over 13 million square kilometers in size, with almost 90% of its area classified as arid or ex- tremely arid with very little precipitation, extremely high evaporation and almost no vegetation cover. The region is classified in many international reports as the poorest region in the world in the context of renewable water resources and critical water scarcity which hinders the socio-economfic development of many countries in this region. The rapidly increasing population has reduced the per capita share of renewable water to less than the poverty line of 1,000 m3/（capita＇a） and, in some Arab countries, to less than the extreme poverty line of 500 m3/（capita＇a）. This has led to over-exploitation of non-renewable groundwater and desalination of salty water in many countries with considerable costs and contamination of many renewable sources. Atmospheric processes re- sponsible for aridity in the Arab region are projected to intensify due to climate change, resulting in an alarming decrease in pre- cipitation and increase in evaporation rates. Many concerned entities in the region consider water security as a key element for food security and ultimately political stability. Hence, various efforts have been exerted to identify key problems and suggested solutions. The Arab Water Ministers Council of the Arab League, as well as Reports of the Arab Forum for the Environment and Development （AFED） and the recommendations of the 13th Regional Meeting of the Arab National Committees of the Interna- tional Hydrological Programme of UNESCO （niP）, have all made similar recommendations on the need to address the issues of water scarcity in the Arab region which will be further discussed in this paper. However, none of these reports focused on ＂Water Conservation＂ as an equally important action for coping with water scarcity in the region. There are many definitions for ＂Water Conservation＂ in the scientific literature, including huge water savings

关键词： arid zone water scarcity water security irrigation efficiency climate change water harvesting water reuse

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Global threshold dynamics of an age structured alcoholism model

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International Journal of Biomathematics 2021年第3期14卷 153-186页

作者： Soufiane Bentout salih Djilali Abdenasser Chekroun Laboratoire d'Analyse Non Linéaire et Mathématiques Appliquées University of TlemcenTlemcen 13000Algeria Department of Mathematics and Informatics Belhadj Bouchaib University Center of Ain TemouchentAin Temouchent 46OOOAlgeria Faculty of Exact and Computer Sciences Mathematic DepartmentHassiba Benbouali UniversityChiefAlgeria University of Abou Bekr Belkaid Tlemcen Tlemcen 13000Algeria

We consider in this research an age-structured alcoholism *** global behavior of the model is *** is proved that the system has a threshold dynamics in terms of the basic reproduction number(BRN),where we obtained that alcohol-free equilibrium(AFE)is globally asymptotically stable(GAS)in the case R_(0)≤1,but for R_(0)>1 we found that the system persists and the nontrivial equilibrium(EE)is ***,the effects of the susceptible drinkers rate and the repulse rate of the recovers to alcoholics are investigated,which allow us to provide a proper strategy for reducing the spread of alcohol use in the studied *** obtained mathematical results are tested numerically next to its biological relevance.

关键词： Mathematical biology age-structured partial differential equations alcohol model uniform persistence global behavior Lyapunov function

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Resource Exhaustion Attack Detection Scheme for WLAN Using Artificial Neural Network

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Computers, Materials & Continua 2023年第3期74卷 5607-5623页

作者： Abdallah Elhigazi Abdallah Mosab Hamdan Shukor Abd Razak Fuad A.Ghalib Muzaffar Hamzah Suleman Khan Siddiq Ahmed Babikir ali Mutaz H.H.Khairi Sayeed salih Faculty of Engineering Future UniversityKhartoum 10553Sudan Faculty of Computing and Informatics Universiti Malaysia SabahKota Kinabalu88400Malaysia Information Assurance and Security Research School of ComputingUniversiti Teknologi MalaysiaJohor81310Malaysia School of Psychology and Computer Science University of Central LancashirePreston PR12HEUK Deaptement of Management Information Systems College of Administrative ScienceApplied Science UniversityAl Eker623Bahrain Deaptement of Information Technology College of Computer and Information SciencesKing Saud UniversityRiyadh11461Saudi Arabia

IEEE 802.11 Wi-Fi networks are prone to many denial of service(DoS)attacks due to vulnerabilities at the media access control(MAC)layer of the 802.11 *** to the data transmission nature of the wireless local area network(WLAN)through radio waves,its communication is exposed to the possibility of being attacked by illegitimate ***,the security design of the wireless structure is vulnerable to versatile *** example,the attacker can imitate genuine features,rendering classificationbased methods inaccurate in differentiating between real and false *** security standards have been proposed over the last decades to overcome many wireless network attacks,effectively detecting such attacks is crucial in today’s real-world *** paper presents a novel resource exhaustion attack detection scheme(READS)to detect resource exhaustion attacks *** proposed scheme can differentiate between the genuine and fake management frames in the early stages of the attack such that access points can effectively mitigate the consequences of the *** scheme is built through learning from clustered samples using artificial neural networks to identify the genuine and rogue resource exhaustion management frames effectively and efficiently in *** proposed scheme consists of four modules whichmake it capable to alleviates the attack impact more effectively than the related *** experimental results show the effectiveness of the proposed technique by gaining an 89.11%improvement compared to the existing works in terms of detection.

关键词： 802.11 media access control(MAC) wireless local area network(WLAN) artificial neural network denial-of-service(DoS)

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Clinical presentation, diagnosis and treatment of vulvovaginitis in girls: a current approach and review of the literature

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World Journal of Pediatrics 2017年第2期13卷 101-105页

作者： (I)lke Beyitler salih Kavukcu Department of Pediatrics Near East University HospitalNicosiaNorth Cyprus Department of Pediatrics Division of NephrologyNear East University HospitalNicosiaNorth Cyprus

Background:Vulvovaginitis is the most common cause of gynecological complaints in children and young *** of the factors which cause vulvovaginitis include hypoestrogenism,the anatomical proximity of rectum and delicate vulvar skin and vaginal *** sources:We made a literature search with Pubmed,Medline and Cochrane database from January 2002 to May 2015 in English language using the key words vulvovaginitis,children,clinical,diagnosis and ***:Vulvovaginitis in girls is usually caused by non-specific factors and hygiene measures,bioyoghurt and avoidance of chemical irritants are generally *** control if necessary and prevention of voiding dysfunction are *** flora is important in girls and results should be interpreted with clinical features to decide whether an isolated microorganism is part of the normal microflora or is the cause of symptomatic *** treatment is generally considered in case of a detected pathogen *** of a sexually transmitted organism requires further *** disease may not always indicate a foreign body but it must be taken into *** and parents are encouraged psychologically in all steps of evaluation,diagnosis and ***,nanotechnology and petroleum jelly are other important treatment options used in ***:In this review,we present current approach to the presentation and management of vulvovaginitis in *** disorder requires a comprehensive evaluation in all steps of diagnosis,differential diagnosis and treatment.

关键词： children diagnosis treatment vulvovaginitis

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Backward,Hopf bifurcation in a heroin epidemic model with treat age

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International Journal of Modeling, Simulation, and Scientific Computing 2021年第2期12卷 198-222页

作者： Soufiane Bentout salih Djilali Behzad Ghanbari Laboratoire d’Analyse Non Lin´eaire et Math´ematiques Appliqu´ees Universit´e de Tlemcen TlemcenAlgeria Department of Basic Science Kermanshah University of Technology KermanshahIran Faculty of Exact and Computer Sciences Mathematic Department Hassiba Benbouali UniversityChlefAlgeria §Department of Mathematics and Informatics Belhadj Bouchaib University Center of Ain Temouchent BP 284 RP 46000Algeria

Heroin is considered as damage on the health of the *** this paper,we consider a heroin epidemic model with treat age,where the inner rivalry in between the drug users for a small dose of drugs is *** influence of treatment period for a drug consumer before quitting treatment is investigated,where it is obtained that the considered model can undergo backward bifurcation,which shows the possibility of having two endemic equilibriums,this type of bifurcation is discussed in terms of the basic reproduction number *** bifurcation diagram is drown in the case of an age structured ***,we show the existence of Hopf bifurcation is shown under suitable conditions on the model *** obtained mathematical results are confirmed numerically.

关键词： Backward bifurcation heroin epidemic age-structured model Hopfbifurcation

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不对称故障下的LCC-HVDC系统连续换相失败抑制策略研究

不对称故障下的LCC-HVDC系统连续换相失败抑制策略研究

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作者： Ahmed Omer salih 山东大学

学位级别：硕士

高压直流输电是一种成熟的技术,主要用于远距离传输大容量电力,连接异步网络或海底电缆系统。由于其与现有系统的互连和新技术的应用,电力系统的复杂性逐渐增加,同时,许多经济和其他限制因素迫使电力公司在最大稳定性极限附近运行其系统... 详细信息

高压直流输电是一种成熟的技术,主要用于远距离传输大容量电力,连接异步网络或海底电缆系统。由于其与现有系统的互连和新技术的应用,电力系统的复杂性逐渐增加,同时,许多经济和其他限制因素迫使电力公司在最大稳定性极限附近运行其系统,并以最低的成本提供可靠和清洁的电力[1]。电力需求的持续增长迫使需要远距离、大容量的高压直流系统进行电力传输。此外,人们越来越有兴趣将可再生能源纳入电网,再次依赖高压直流输电链路。因此,高压直流输电技术的应用是克服这些问题的必要手段。基于线路换相换流器的高压直流（LCC-HVDC）已经证明了它们在远距离传输大容量电力方面的有效性。LCC-HVDC的主要缺点之一是换相故障发生的风险很高。换相故障主要发生在逆变器侧,由于交流系统干扰或控制故障。当发生换向失败故障时,可能会威胁到系统的稳定性,因为它会导致传输功率的扰动冲击。此外,它还会增加逆变器的无功功耗,这在弱交流系统的情况下是不可取的。为了限制换相失败的影响,提出了几种方法。无论是在改进一次设备方面,还是在改进控制系统方面。改进控制系统是采用最多的,因为它具有可行性,并且可靠性高。在通过改进控制系统来预防换相故障时,有两种主要方法可用于提高系统性能,无论是通过修改触发角,还是使用单独的控制系统来控制熄弧角。但是,为了能够制定有效的预防策略,应充分利用控制系统,以避免应用预防策略和增加系统的无功功率,这是不希望的。尽管不对称故障是换相失败的主要原因[1],但迄今为止,用于分析和预防LCC-HVDC换相故障的模型并没有准确地解决相位移问题,无论是在检测策略方面还是在换流阀级控制下发出触发角。这将限制对换相失败故障的检测和预防。在本论文中,提出了有效的策略来有效地检测和防止换相故障。本论文的贡献可以总结如下:（1）提出一个准确的模型:在不对称故障期间,系统将发生相位移。在本论文中,开发了一个基于序分量的模型,以获取系统上可能发生的不同相位移。相位移尤其会影响系统的触发脉冲。如果在晶闸管不正向偏置时施加触发脉冲,则会发生换相故障。因此,需要随时检测系统的相位角,以有效地控制系统。（2）提出强化策略:基于提出的精确模型,开发有效利用控制系统的有效方法。为了提高PLL的性能,并能够在晶闸管正向偏置时提供触发脉冲,使用提出的数学模型提供电压,并使用基于Tan-Sun的PLL来提供触发脉冲。通过使用这种方法,即使故障持续一段时间,也可以有效地防止连续换相失败故障,而无需增加换相面积。为了验证所提出的抑制换相失败的方法,使用PSCAD/EMTDC进行了仿真。在逆变器终端施加不同类型的故障,以研究系统性能。故障电感在较大的范围内变化,以验证所提出的方法。此外,还考虑了不同强度的系统,以确保该方法在不同条件下的有效运行。

关键词：换相失败不对称故障换相失败的预防序分量 Tan-Sun坐标变换

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Matrix metalloproteinase gene expressions might be oxidative stress targets in gastric cancer cell lines

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Chinese Journal of Cancer Research 2013年第3期25卷 322-333页

作者： salih Gencer Anil Cebeci Meliha Burcu Irmak-Yazicioglu Department of Genetics and Bioengineering Faculty of Engineering Fatih University Department of Molecular Biology and Genetics Faculty of Engineering and Natural Sciences Uskudar University Department of Molecular Biology and Genetics Faculty of Arts and Sciences Halic University

Oxidative stress is linked to increased risk of gastric cancer and matrix metalloproteinases （MMPs） are important in the invasion and metastasis of gastric cancer. We aimed to analyze the effect of the accumulation of oxidative stress in the gastric cancer MKN-45 and 23132/87 cells following hydrogen peroxide （H202） exposure on the expression patterns of MMP-1, MMP-3, MMP-7, MMP-9, MMP-10, MMP- 1 1, MMP- 12, MMP-14, MMP- 15, MMP- 17, MMP-23, MMP-28, and β-catenin genes. Methods： The mRNA transcripts in the cells were determined by RT-PCR. Following H202 exposure, oxidative stress in the viable cells was analyzed by 2＇,7＇-dichlorofluorescein diaeetate （DCFH-DA）. Caffeie acid phenethyl ester （CAPE） was used to eliminate oxidative stress and the consequence of H2O2 exposure and its removal on the expressions of the genes were evaluated by quantitative real-time PCR. Results： The expressions of MMP-1, MMP-7, MMP-14, MMP-15, MMP-17 and β-catenin in MKN-45 cells and only the expression of MMP-15 in 23132/87 cells were increased. Removal of the oxidative stress resulted in decrease in the expressions of MMP genes of which the expressions were increased after H202 exposure. β-catenin, a transcription factor for many genes including MMPs, also displayed decreased levels of expression in both of the cell lines following CAPE treatment. Conclusions： Our data suggest that there is a remarkable link between the accumulation of oxidative stress and the increased expressions of MMP genes in the gastric cancer cells and MMPs should be considered as potential targets of therapy in gastric cancers due to its continuous exposure to oxidative stress.

关键词： Oxidative stress hydrogen peroxide (H202) matrix metalloproteinases (MMPs) expression eaffeicacid phenethyl ester (CAPE)

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Rapprochement in Israel-Saudi Foreign Policy:Moving on Tiptoes to a Normalization Process?

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Asian Journal of Middle Eastern and Islamic Studies 2022年第3期16卷 327-341页

作者： salih Bıçakcı Hazal Muslu El Berni Kadir Has University IstanbulTurkey

The possibility of a Saudi rapprochement with Israel has been continuously influenced by the the domestic barriers within the Saudi community and the Saudi historical narratives on the regional security perceptions of the Saudi *** the appointment of Prince Mohammed bin Salman as the Minister of Defense in 2015,King Salman’s government adopted a new discourse in domestic and foreign policy built upon a redefined Saudi identity rhetorically distanced from its Islamic neighbours and moved towards a nationalised *** unstable nature of the regional security dynamics forces the kingdom to actively reconstruct new security routines based on the emerging regional security dynamics and repositions the *** this juncture,this research aims at understanding the rationality of the rise and fall of the intensity of Saudi foreign policy towards a normalisation process with Israel within the borders of the redefined Saudi national identity and regional threat perceptions.

关键词： Saudi Arabia Israel rapprochement normalisation regional security identity Iran

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Performance investigation of LAMBDA and bootstrapping methods for PPP narrow-lane ambiguity resolution

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Geo-Spatial Information Science 2021年第4期24卷 604-614页

作者： Omer Faruk Atiz Sermet Ogutcu salih alcay Pan Li Ilkay Bugdayci Department of Geomatics Engineering Necmettin Erbakan UniversityKonyaTurkey Department of Geodesy and Remote Sensing German Research Centre for GeosciencesPotsdamGermany

Precise point positioning with ambiguity resolution(PPP-AR)is a powerful tool for geodetic and time-constrained applications that require high *** performance of PPP-AR highly depends on the reliability of the correct integer carrier-phase ambiguity *** this study,the performance of narrow-lane ambiguity resolution of PPP using the Least-squares AMBiguity Decorrelation(LAMBDA)and bootstrapping methods is extensively investigated using real data from 55 IGS stations over one-month in *** PPP with 24-,12-,8-,4-,2-,1-and½-h sessions using two different cutoff angles(7°and 30°)was conducted with three PPP modes:***-float and two kinds of ambiguity-fixed PPP using the LAMBDA and bootstrapping methods for narrow-lane AR,*** results show that the LAMBDA method can produce more reliable results for 2 hour and shorter observation sessions com-pared with the bootstrapping method using a 7°cutoff *** a 30°cutoff angle,the LAMBDA method outperforms the bootstrapping method for observation sessions of 4 h and *** long observation times,the bootstrapping method produced much more accurate coordinates compared with the LAMBDA method without considering the wrong fixes *** results also show that occurrences of fixing the wrong integer ambiguities using the bootstrapping method are higher than that of the LAMBDA method.

关键词： Ambiguity resolution narrow-lane Precise point positioning(PPP) LAMBDA bootstrapping

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Effect of nettle(Urtica dioica) extract on gentamicin induced nephrotoxicity in male rabbits

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Asian Pacific Journal of Tropical Biomedicine 2015年第9期5卷 729-732页

作者： Nadia Abdulkarim salih Pharmacology Department of Basic Sciences College of Veterinary Medicine University of Sulaimani

Objective:To investigate the antioxidant ef ect of an orally administered ethanol extract of nettle(Urtica dioica) and its protective role in preventing or ameliorating oxidative stress as a major factor in gentamicin-induced nephrotoxicity in male rabbits. Methods: Twenty rabbits were divided into 4 equal groups:(G1) control group,(G2) gentamicin treated group(100 mg/kg),(G3) nettle treated group(100 mg/kg),(G4) combination treated group with both gentamicin(100 mg/kg) and nettle(100 mg/kg) for 10 days. The antioxidant properties of nettle were evaluated using dif erent antioxidant tests, such as determination of glutathione and malondialdehyde levels and total phenolic content analysis. Results: Biochemical and histopathological study revealed that gentamicin caused nephrotoxicity observed clearly in the histopathological section of the kidney in the gentamicin treated group. Serum creatinine and blood urea nitrogen were biochemical indicators for nephrotoxicity which increased signii cantly in gentamicin treated group; other groups have no signii cant change in these two parameters. Nettle extract protected the rabbits from alteration in the level of blood urea nitrogen and serum creatinine when given after inducing of gentamicin nephrotoxicity. The nettle treated group showed a great ef ect as an antioxidant factor by increasing the glutathione level and reducing malondialdehyde level. No signii cant changes in biochemical parameters and no renal histopathological changes observed in the groups treated with nettle extract, which meant nettle had powerful antioxidant activity. Conclusions: Therefore, it can be assumed that the nephroprotective ef ect shown by nettle in gentamicin-induced nephrotoxicity can reserve intracellular levels of biological pathways and supportively enhance excretion of toxic levels of gentamicin.

关键词： Antioxidant activity Nettle Urtica dioica Gentamicin Herbal medicine Histopathological study and nephrotoxicity

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