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The impact of foot reflexology on fatigue and sleep quality in school-aged children undergoing hemodialysis
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作者 Amal Hashem MOHAMED Mostafa SHABAN +3 位作者 Huda Hamdy MOHAMMED Randa Mohamed ABOBAKER Salman Hamdan ALSAQRI Rania Abd-Elnaby Mohammed ALLAM 《Journal of Integrative Nursing》 2024年第2期76-82,共7页
Objective:This study aimed to evaluate the effects of foot reflexology on fatigue and sleep quality in school-aged children receiving hemodialysis.Methods:A quasi-experimental pretest-posttest design was utilized.Thir... Objective:This study aimed to evaluate the effects of foot reflexology on fatigue and sleep quality in school-aged children receiving hemodialysis.Methods:A quasi-experimental pretest-posttest design was utilized.Thirty children of ages 6-12 undergoing in-center hemodialysis were recruited.The Pittsburgh Sleep Quality Index(PSQI)and Inventory of Fatigue Symptom(IFS)scales were administered at baseline.Participants then received 30 min of foot reflexology massage before hemodialysis sessions 3 days per week for 12 weeks.Posttest administration of the sleep and fatigue scales occurred after the intervention period.Results:Reflexology massage led to significant improvements in sleep quality components,including duration(0%-30%normal sleepers),efficiency(0%-50%>85%),latency(50%-0%>60 min),disturbances,and daytime dysfunction.The mean PSQI score decreased from 18.2 to 9.7(P<0.05).Fatigue severity substantially decreased,with the mean IFS score improving from 105.7 to 64.1(P<0.05).Conclusion:Foot reflexology is an effective nursing intervention for reducing fatigue and improving sleep quality in children on hemodialysis,warranting integration into routine care. 展开更多
关键词 FATIGUE HEMODIALYSIS MASSAGE PEDIATRIC REFLEXOLOGY SLEEP
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Prevalence of intestinal parasite infections among patients in local public hospitals of Hail,Northwestern Saudi Arabia 被引量:2
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作者 Omar Hassen Amer Ibraheem M Ashankyty Najoua Al Sadok Haouas 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第1期41-45,共5页
Objective:To evaluate the prevalence of intestinal parasites among patients in Hail,Northwestern Saudi Arabia.Methods:Stool samples were collected from 130 patients(69females and 61 males) in Hail General Hospital.Eac... Objective:To evaluate the prevalence of intestinal parasites among patients in Hail,Northwestern Saudi Arabia.Methods:Stool samples were collected from 130 patients(69females and 61 males) in Hail General Hospital.Each sample was examined by direct wet mount microscopic examination using both normal saline and Lugol's iodine preparation and concentration techniques using salt and formol-ether solutions.Permanent stained smears were performed for intestinal coccidian using modified Ziehl-Neelsen technique.Results:The overall prevalence of intestinal parasitic infection was 45.38%(59 cases).Forty-four(33.84%)were found to be infected with one or more intestinal protozoa.5(3.84%) were infected with helminthes and 10(7.69%) had mixed infection with both helminthes and protozoa.The most common intestinal helminth detected was Ancyloxtoma duvdenale(n=5.3.84%),followed by Ascaris lumlmcnidex.Taenia sp.and Trichuris trichiura(n=2 for each species,1.5%).For intestinal protozoa,the coccidian Cryptosporidium parvum(n=25,19.23%) was the most common followed by Entamoeba histolytica/dispur(n=21,16.15%),Giurdia lamblia(n=15,11.54%),Entamoeba coli(n=5.3.85%) and Blastocysts hominis(n=3,2.30%).The prevalence of intestinal parasitic infections in females was significantly higher than in males(P<0.05).Conclusions:This is the first study highlighting that intestinal parasites are still an important public health problem in Northwestern Saudi Arabia Therefore,health education would be the best way to prevent from intestinal parasite infections which are mainly food borne diseases. 展开更多
关键词 PREVALENCE INTESTINAL parasites HAIL KSA
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Awareness of Folic Acid Intake among Women in the Childbearing Age in Hail Region—Saudi Arabia 被引量:1
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作者 Murad Al-Holy Ala’a Eideh +2 位作者 Suneetha Epuru Dima Abu-Jamous Ibrahim Ashankyty 《Food and Nutrition Sciences》 2013年第1期49-55,共7页
This study evaluated the awareness of folic acid, timing of folic acid supplementation and source of knowledge of folic acid intake in Hail region-Saudi Arabia. A sample of 300 married women in the childbearing age (1... This study evaluated the awareness of folic acid, timing of folic acid supplementation and source of knowledge of folic acid intake in Hail region-Saudi Arabia. A sample of 300 married women in the childbearing age (19 - 45 years) in Hail in the period between October/2011 and January/2012 participated in a survey study regarding awareness and use of folic acid before and during pregnancy. Participant women were asked to respond to different questions related to age, level of education, occupation, monthly income, gravidity, and other information concerning folic acid awareness, specific knowledge, supplementation practices, and source of knowledge about the preconceptional intake of folic acid. While 91.0% of the subjects were aware of folic acid, 81.0% knew that folic acid could prevent neural tube defects and 84.0% of the subjects took folic acid prior or during a certain stage of pregnancy. Nonetheless, only 10.0% of the subjects who proclaimed that they know the proper timing for folic acid supplementation recognized that folic acid should be taken prior and during the first trimester of pregnancy. University education was the strongest predictor of folic acid knowledge and university educated subjects had significantly (P P 展开更多
关键词 Folic acid AWARENESS Supplementation SAUDI ARABIA
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Nanotechnology-based gene therapy as a credible tool in the treatment of Alzheimer’s disease 被引量:4
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作者 Aziz Unnisa Nigel H.Greig Mohammad Amjad Kamal 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第10期2127-2133,共7页
Toxic aggregated amyloid-βaccumulation is a key pathogenic event in Alzheimer’s disease.Treatment approaches have focused on the suppression,deferral,or dispersion of amyloid-βfibers and plaques.Gene therapy has ev... Toxic aggregated amyloid-βaccumulation is a key pathogenic event in Alzheimer’s disease.Treatment approaches have focused on the suppression,deferral,or dispersion of amyloid-βfibers and plaques.Gene therapy has evolved as a potential therapeutic option for treating Alzheimer’s disease,owing to its rapid advancement over the recent decade.Small interfering ribonucleic acid has recently garnered considerable attention in gene therapy owing to its ability to down-regulate genes with high sequence specificity and an almost limitless number of therapeutic targets,including those that were once considered undruggable.However,lackluster cellular uptake and the destabilization of small interfering ribonucleic acid in its biological environment restrict its therapeutic application,necessitating the development of a vector that can safeguard the genetic material from early destruction within the bloodstream while effectively delivering therapeutic genes across the bloodbrain barrier.Nanotechnology has emerged as a possible solution,and several delivery systems utilizing nanoparticles have been shown to bypass key challenges regarding small interfering ribonucleic acid delivery.By reducing the enzymatic breakdown of genetic components,nanomaterials as gene carriers have considerably enhanced the efficiency of gene therapy.Liposomes,polymeric nanoparticles,magnetic nanoparticles,dendrimers,and micelles are examples of nanocarriers that have been designed,and each has its own set of features.Furthermore,recent advances in the specific delivery of neurotrophic compounds via gene therapy have provided promising results in relation to augmenting cognitive abilities.In this paper,we highlight the use of different nanocarriers in targeted gene delivery and small interfering ribonucleic acid-mediated gene silencing as a potential platform for treating Alzheimer’s disease. 展开更多
关键词 Alzheimer’s disease amyloid-β BACE1 gene silencing gene therapy nanoparticle NEUROTROPHINS small interfering ribonucleic acid
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Patterns of Caffeinated Energy Drinks Consumption among Adolescents and Adults in Hail, Saudi Arabia
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作者 Mo’ez Al-Islam Ezzat Faris 《Food and Nutrition Sciences》 2014年第2期158-168,共11页
Caffeinated energy drinks have become more popular in the last decades, especially amongst adolescents and young adults in different parts of the globe. The study aims to investigate the frequency of energy-drink cons... Caffeinated energy drinks have become more popular in the last decades, especially amongst adolescents and young adults in different parts of the globe. The study aims to investigate the frequency of energy-drink consumption and associated factors in an arbitrary group of adults and adolescents living in Hail/Saudi Arabia. A cross-sectional study was conducted and included which randomly selected 1062 participants (867 males and 195 females) from universities, colleges, middle-to-higher schools and social settings. Data collection was conducted using a self-administered standard tested questionnaire. The current study revealed about 46% had drunk energy drinks, while about 54% did not ever drink energy drinks. Out of the energy drinks consumers, 37% started drinking during the primary school, 64% consumed energy drinks on a daily basis, and 44% consumed two or more cans per day. Reasons behind not taking energy drinks were the belief that they are unhealthy drinks (about two-thirds of non-drinkers), and lack of curiosity for energy drinks (18%). Other reasons such as unaccepted taste, thought to be obesogenic, and the possibility of getting addicted were also reported. From all participants, only 23% and 4% knew about the presence of caffeine and taurine, respectively, in energy drinks. Unreliable resources were the major sources of knowledge about energy drinks and their health effects. Awareness of community about the ingredients and potential hazards of energy drinks should be raised and encouraged by designing and implementing educational programs. 展开更多
关键词 Energy DRINKS Knowledge ADULTS and Adolescents SAUDI ARABIA
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Land Cover Classification of Hail—Saudi Arabia Using Remote Sensing
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作者 Mohamed E. Hereher Ahmed M. Al-Shammari Shehta E. Abd Allah 《International Journal of Geosciences》 2012年第2期349-356,共8页
A set of five satellite images from the Landsat satellite, Moderate Resolution Imaging Spectroradiometer (MODIS) and the Shuttle Radar Topography Mission (SRTM) sensors has been operated to analyze land cover and topo... A set of five satellite images from the Landsat satellite, Moderate Resolution Imaging Spectroradiometer (MODIS) and the Shuttle Radar Topography Mission (SRTM) sensors has been operated to analyze land cover and topography of the Hail region, Saudi Arabia. Image processing techniques included unsupervised classification for clustering four land cover units in the MODIS image, namely: plains, sand dunes, mountains, and cultivated lands. The SRTM image was classified to produce a thematic topographic map with 100 m elevation interval. The normalized difference vegetation index (NDVI) was applied in the Landsat images as a proxy to the change of agricultural land in Hail between 1972 and 2000. Results showed that Hail region occurs at a high plateau. Minimum elevation occurs at its northeastern corner and peaks occur at the southwestern side. The surface area of Hail is estimated at 115,690 km2. The majority of Hail area is represented by plains and sand dunes. Cultivated lands increased from 9500 ha in 1972 to 139,000 ha in 2010. 展开更多
关键词 LAND COVER REMOTE SENSING HAIL KSA
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The Economic Impact of Artificial Intelligence on Healthcare: A Literature Review
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作者 Badr Alnasser 《E-Health Telecommunication Systems and Networks》 2023年第3期35-48,共14页
Background: This review delves into the effects of artificial intelligence (AI) on healthcare, which is a crucial aspect considering the increasing costs of healthcare worldwide. While there is potential for AI to enh... Background: This review delves into the effects of artificial intelligence (AI) on healthcare, which is a crucial aspect considering the increasing costs of healthcare worldwide. While there is potential for AI to enhance healthcare delivery and efficiency, there are still uncertainties surrounding its effectiveness, value, and broader adoption. This comprehensive literature review aims to explore and synthesize existing knowledge on the economic impact of AI in healthcare. The primary objective of this review is to understand the potential cost savings and efficiency improvements associated with the deployment of AI in healthcare settings. By highlighting the economic implications of AI, this review seeks to offer insights into the value proposition of investing in AI technologies for stakeholders such as healthcare providers, payers, and policymakers. Methods: To conduct this review, we conducted a search of literature from 2020 to 2023 across three databases: PubMed, Scopus and Google Scholar. We specifically focused on studies that discuss the impacts of AI in healthcare and include cost evaluations, using combinations of keywords related to AI, economics, healthcare, and cost evaluation. The inclusion criteria were studies that conducted some form of economic evaluation related to AI in healthcare settings, while exclusion criteria were studies without a cost evaluation component. Data extraction and quality assessment using the CASP checklist were undertaken on the final set of included studies. Results: After screening studies, we identified 10 out of a total of 28 studies and reports that met our criteria of outlining any form of economic impact and evaluation of AI in healthcare settings. Based on our findings, implementing AI in healthcare could potentially lead to cost savings. Several studies suggest savings ranging from $200 billion to $360 billion in the United States alone. The use of AI in healthcare sectors such as ophthalmology, radiology and disease screening has shown positive economic impacts. Conclusion: While AI has potential for cost savings and efficiency improvements, in healthcare settings, it’s crucial to conduct detailed context specific cost evaluations to optimize the adoption and implementation strategies of AI. 展开更多
关键词 Artificial Intelligence Healthcare Economic Impact Cost Evaluation Literature Review
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Application of Plant Growth-Promoting Bacteria as an Eco-Friendly Strategy for Mitigating the Harmful Effects of Abiotic Stress on Plants
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作者 Ahmed Hassan Abdou Omar Abdullah Alkhateeb +5 位作者 Hossam Eldin Hamed Mansour Hesham S.Ghazzawy Muayad Saud Albadrani Nadi Awad Al-harbi Wasimah B.Al-Shammari Khaled Abdelaal 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第12期3305-3321,共17页
Plant growth-promoting bacteria(PGPB)play an important role in improving agricultural production under several abiotic stress factors.PGPB can be used to increase crop growth and development through hormonal balance a... Plant growth-promoting bacteria(PGPB)play an important role in improving agricultural production under several abiotic stress factors.PGPB can be used to increase crop growth and development through hormonal balance and increase nutrient uptake.The positive effect of PGPB may be due to its pivotal role in morphophysiological and biochemical characteristics like leaf number,leaf area,and stem length.Furthermore,relative water content,chlorophyll content,carotenoids,antioxidant enzymes,and plant hormones were improved with PGPB treatment.Crop yield and yield components were also increased with PGPB treatment in numerous crops.The anatomical structure of plant organs was increased such as lamina thickness,stem diameter,xylem vessel diameter,and number of xylem vessels as well as phloem thickness under treatment with PGPB.Additionally,PGPB can alleviate the negative effects of several abiotic stresses by regulating the antioxidant defense system to scavenge the reactive oxygen species resulting in an improvement of yield production in the stressed plants.Additionally,gene expressions were controlled by calcium ion modulation during secondary messengers that act upon calcium-dependent protein kinase and protein phosphatases.This includes many transcription factors such as MYB,AP2/ERF,bZIP,and NAC which regulate genes related to salinity stress signals.PGPB can demonstrate induction genes of signaling under abiotic stress conditions.This review gives an outline of the PGPB role in alleviating the harmful effects of abiotic factors such as salinity,drought,and heat associated with the improvement of the morpho-physiological and biochemical features especially,leaves and branches number,leaf area,antioxidant compounds,plant hormones,and relative water content. 展开更多
关键词 PGPB SALINITY DROUGHT heat reactive oxygen species ANTIOXIDANTS gene expressions
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The Hierarchical Order of Spaces in Arab Traditional Towns: The Case of Najd, Saudi Arabia 被引量:3
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作者 Mohammed Mashary Alnaim 《World Journal of Engineering and Technology》 2020年第3期347-366,共20页
The built environment faces many challenges in accommodating multi-cultural diversity and migrating from the suburbs, which led to different places being isolated or neglected. Sub-identities established by a specific... The built environment faces many challenges in accommodating multi-cultural diversity and migrating from the suburbs, which led to different places being isolated or neglected. Sub-identities established by a specific group of people become isolated and away from the shared identity that the built environment established for itself. We examine this issue in the Najdi </span><span style="font-family:Verdana;">built environment by examining how Najdi locals generated a holistic</span><span style="font-family:Verdana;"> hierarchical order of specs. This paper argues that the spatial order encouraged locals to develop a shared and agreed mechanism while in parallel, it gave individuals the ability to modify their places without affecting that shared holistic spatial order. 展开更多
关键词 HIERARCHY Order Space Built Environment Najd Urban Fabric CULTURE Space Syntax
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Multiquadric Radial Basis Function Approximation Scheme for Solution of Total Variation Based Multiplicative Noise Removal Model 被引量:1
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作者 Mushtaq Ahmad Khan Ahmed BAltamimi +4 位作者 Zawar Hussain Khan Khurram Shehzad Khattak Sahib Khan Asmat Ullah Murtaza Ali 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第1期55-88,共34页
This article introduces a fastmeshless algorithm for the numerical solution nonlinear partial differential equations(PDE)by Radial Basis Functions(RBFs)approximation connected with the Total Variation(TV)-basedminimiz... This article introduces a fastmeshless algorithm for the numerical solution nonlinear partial differential equations(PDE)by Radial Basis Functions(RBFs)approximation connected with the Total Variation(TV)-basedminimization functional and to show its application to image denoising containing multiplicative noise.These capabilities used within the proposed algorithm have not only the quality of image denoising,edge preservation but also the property of minimization of staircase effect which results in blocky effects in the images.It is worth mentioning that the recommended method can be easily employed for nonlinear problems due to the lack of dependence on a mesh or integration procedure.The numerical investigations and corresponding examples prove the effectiveness of the recommended algorithm regarding the robustness and visual improvement as well as peak-signal-to-noise ratio(PSNR),signal-to-noise ratio(SNR),and structural similarity index(SSIM)corresponded to the current conventional TV-based schemes. 展开更多
关键词 Denoised image multiplicative and speckle noises total variation(TV)filter Euler-Lagrange restoration equation multiquadric radial basis functions meshless and mesh-based schemes
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Anti-Synchronization of Chaotic Systems via Adaptive Sliding Mode Control 被引量:1
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作者 Wafaa Jawaada M.S.M.Noorani M.Mossa Al-sawalha 《Chinese Physics Letters》 SCIE CAS CSCD 2012年第12期36-38,共3页
An anti-synchronization scheme is proposed to achieve the anti-synchronization behavior between chaotic systems with fully unknown parameters.A sliding surface and an adaptive sliding mode controller are designed to g... An anti-synchronization scheme is proposed to achieve the anti-synchronization behavior between chaotic systems with fully unknown parameters.A sliding surface and an adaptive sliding mode controller are designed to gain the anti-synchronization.The stability of the error dynamics is proven theoretically using the Lyapunov stability theory.Finally numerical results are presented to justify the theoretical analysis. 展开更多
关键词 parameters. theory. STABILITY
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Adaptive Increasing-Order Synchronization and Anti-Synchronization of Chaotic Systems with Uncertain Parameters 被引量:1
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作者 M.Mossa Al-sawalha M.S.M.Noorani 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第11期49-51,共3页
We elaborate the concept of increasing-order synchronization and anti-synchronization of chaotic systems via an adaptive control scheme and modulation parameters.It is shown that the dynamical evolution of a third-ord... We elaborate the concept of increasing-order synchronization and anti-synchronization of chaotic systems via an adaptive control scheme and modulation parameters.It is shown that the dynamical evolution of a third-order chaotic system can be synchronized and anti-synchronized with a fourth-order chaotic system even though their parameters are unknown.Theoretical analysis and numerical simulations are carried out to verify the results. 展开更多
关键词 parameters CHAOTIC system
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Synthesis and Characterization of Alkaline-Earth Metal (Ca, Sr, and Ba) Doped Nanodimensional LaMnO_(3) Rare-Earth Manganites 被引量:1
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作者 Asma Khalid Saadat Anwar Siddiqi Affia Aslam 《Chinese Physics Letters》 SCIE CAS CSCD 2013年第7期217-220,共4页
The substitution of divalent cations of alkaline-earth elements in nanodimensional structures of rare-earth manganites produces advanced materials with potential electrical and magnetic functionalities.A systematic in... The substitution of divalent cations of alkaline-earth elements in nanodimensional structures of rare-earth manganites produces advanced materials with potential electrical and magnetic functionalities.A systematic investigation of La_(0.65)A_(0.35)MnO_(3)(A=Ca,Sr,Ba)materials synthesized with a modified citrate route adopting ethanol dehydration has been undertaken.The structural and morphological analyses are carried out by using x-ray diffraction and scanning electron microscopy,respectively.Resistivity measurements are performed in variation with temperature to study the electrical transport properties which are found to vary with the size of the A-site cationic radius.Room temperature magnetic measurements are carried out to investigate the type of magnetic phase present in materials.The stability of the magnetic phase and coercivity are found to be dependent on the size of nanocrystallites. 展开更多
关键词 materials. EARTH DIMENSIONAL
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Anti-diabetics and antimicrobials:Harmony of mutual interplay 被引量:1
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作者 Wael A H Hegazy Azza A H Rajab +1 位作者 Amr S Abu Lila Hisham A Abbas 《World Journal of Diabetes》 SCIE 2021年第11期1832-1855,共24页
Diabetes is one of the four major non-communicable diseases,and appointed by the world health organization as the seventh leading cause of death worldwide.The scientists have turned over every rock in the corners of m... Diabetes is one of the four major non-communicable diseases,and appointed by the world health organization as the seventh leading cause of death worldwide.The scientists have turned over every rock in the corners of medical sciences in order to come up with better understanding and hence more effective treatments of diabetes.The continuous research on the subject has elucidated the role of immune disorders and inflammation as definitive factors in the trajectory of diabetes,assuring that blood glucose adjustments would result in a relief in the systemic stress leading to minimizing inflammation.On a parallel basis,microbial infections usually take advantage of immunity disorders and propagate creating a pro-inflammatory environment,all of which can be reversed by antimicrobial treatment.Standing at the crossroads between diabetes,immunity and infection,we aim in this review at projecting the interplay between immunity and diabetes,shedding the light on the overlapping playgrounds for the activity of some antimicrobial and anti-diabetic agents.Furthermore,we focused on the antidiabetic drugs that can confer antimicrobial or anti-virulence activities. 展开更多
关键词 DIABETES Immune disorders Anti-diabetics Antimicrobials Anti-virulence
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Profile and geographical distribution of reported cutaneous leishmaniasis cases in Northwestern Saudi Arabia,from 2010 to 2013
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作者 Najoua Haouas Omar Amer +2 位作者 Asma Ishankyty Adnan Alazmi Ibrahim Ishankyty 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第4期287-291,共5页
Objective:To describe the profile and geographical distribution of reported cases of cutaneous leishmaniasis(CL)in the province of Hail,Saudi Arabia from 2010 to 2013.Methods:Human data were collected from the dermato... Objective:To describe the profile and geographical distribution of reported cases of cutaneous leishmaniasis(CL)in the province of Hail,Saudi Arabia from 2010 to 2013.Methods:Human data were collected from the dermatology service of both King Khaled and General Hail hospitals.Results:A total of 483 confirmed CL cases were investigated.Cutaneous leishmaniasis follows a seasonal distribution related to the activity of the phlebotomine sand fly fauna.Both saudi and non saudi patients were almost equally infected.The number of reported cases of CL in men was higher than that in females.The frequency of CL was asoociated with age and increased in teenager and adult group.By analyzing the geographical distribution,the majority of Hail districts were affected with this disease.However it is more prevalent in Hail city.Conclusions:The lack of data concerning the parasite,the sand fly fauna and the existing transmission cycles in Hail province make difficult to interpret the reported results and to follow up the spatio-temporal evolution of the disease. 展开更多
关键词 CUTANEOUS leishmaniais EPIDEMIOLOGY HAIL SAUDI ARABIA
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Attitude dynamics and control of spacecraft using geomagnetic Lorentz force
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作者 Yehia A.Abdel-Aziz Muhammad Shoaib 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第1期127-144,共18页
Attitude stabilization of a charged rigid spacecraft in Low Earth Orbit using torques due to Lorentz force in pitch and roll directions is considered. A spacecraft that generates an electrostatic charge on its surface... Attitude stabilization of a charged rigid spacecraft in Low Earth Orbit using torques due to Lorentz force in pitch and roll directions is considered. A spacecraft that generates an electrostatic charge on its surface in the Earth’s magnetic field will be subject to perturbations from the Lorentz force. The Lorentz force acting on an electrostatically charged spacecraft may provide a useful thrust for controlling a spacecraft’s orientation. We assume that the spacecraft is moving in the Earth’s magnetic field in an elliptical orbit under the effects of gravitational, geomagnetic and Lorentz torques. The magnetic field of the Earth is modeled as a non-tilted dipole.A model incorporating all Lorentz torques as a function of orbital elements has been developed on the basis of electric and magnetic fields. The stability of the spacecraft orientation is investigated both analytically and numerically. The existence and stability of equilibrium positions is investigated for different values of the charge to mass ratio(α*). Stable orbits are identified for various values of α*. The main parameters for stabilization of the spacecraft are α*and the difference between the components of the moment of inertia for the spacecraft. 展开更多
关键词 space vehicles atmospheric effects celestial mechanics kinematics and dynamics
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Adaptive Synchronization and Anti-Synchronization of a Chaotic Lorenz–Stenflo System with Fully Unknown Parameters
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作者 M.Mossa Al-sawalha 《Chinese Physics Letters》 SCIE CAS CSCD 2013年第7期26-29,共4页
An adaptive control scheme is developed to study the synchronization and the anti-synchronization behaviors between two identical Lorenz–Stenflo systems with unknown parameters.This adaptive controller is designed ba... An adaptive control scheme is developed to study the synchronization and the anti-synchronization behaviors between two identical Lorenz–Stenflo systems with unknown parameters.This adaptive controller is designed based on Lyapunov stability theory and an analytic expression of the controller with its adaptive laws of parameters is shown.Theoretical analysis and numerical simulations are shown to verify the results. 展开更多
关键词 parameters. verify identical
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Voluntary tax compliance behavior of individual taxpayers in Pakistan
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作者 Ibn e Hassan Ahmed Naeem Sidra Gulzar 《Financial Innovation》 2021年第1期453-475,共23页
Governments settle their financial obligations and pay for the public expenditures largely through finances generated from taxes.For many developing countries like Pakistan,the state authorities are still having diffi... Governments settle their financial obligations and pay for the public expenditures largely through finances generated from taxes.For many developing countries like Pakistan,the state authorities are still having difficulty to achieve tax compliance.Existing literature has yet to traverse individual’s tax compliance behavior on developing countries.The current study,however,explores the relationships among voluntary tax compliance behavior of individual taxpayers with selected economic,social,behavioral and institutional factors.This individual tax compliance behavior is studied through the multi-perspective lenses of the theory of attribution,equity theory,expected utility theory,and social exchange theory.Quantitative design using the survey method was employed to collect data from 435 individual taxpayers through questionnaire.For testing linkage between constructs,through mediation and moderation tests,structural equation modeling technique was used.The results suggest that tax compliance simplicity has a larger impact on tax filing than perception about Government Spending and tax morale.Furthermore,perception of fairness significantly mediates the strengths between morale,simplicity,government spending and compliance behavior. 展开更多
关键词 Compliance behavior Individual taxpayers Pakistan Perception of fairness Tax compliance simplicity Tax morale Voluntary tax
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Microbial Safety of Dried Fish Meat (<i>Kejeik</i>) Produced in Sudan
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作者 Abdel Moneim E. Sulieman Zahra M. A. Hassan Elamin A. Elkhalifa 《Food and Nutrition Sciences》 2014年第7期606-613,共8页
The present study aimed to estimate the microbiological characteristics as well as the safety of traditionally fermented fish product, Kejeik. Kejeik samples were collected from Singah city (Blue Nile) and Kusti city ... The present study aimed to estimate the microbiological characteristics as well as the safety of traditionally fermented fish product, Kejeik. Kejeik samples were collected from Singah city (Blue Nile) and Kusti city (White Nile), Sudan. These samples were previously prepared from Ijl, Nawk and Garmut fish types. The microbiological analyses indicated that Kejeik products were devoid of any harmful bacteria like Salmonella, Listeria monocytogenes and Escherichia coli O157:H7. The highest count of aerobic bacteria was found in Singa ijl Kejeik (SIK) which was 7.6 × 104 cfu/gm. The Enterbacteriaceae isolated from Kejeik samples were identified as Enterobacter cloacae, and their counts in Kejeik prepared from Ijil, Nawk and Garmut fish were 1.09 × 104, 0.93 × 105 and 3.5 × 104 cfu/gm, respectively. On the other hand, the counts of aerobic bacteria in Kejeik prepared from Ijl, Nawk and Garmut were 7.2 × 105, 4.1 × 105 and 3.4 × 105 cfu/gm, respectively. The higher aerobic bacterial load of the various Kejeik samples could be due to improper handling and sanitary condition during the preparation and their moisture contents. The Bacillus isolated from Kejeik samples were identified as Bacillus cereus, and the counts of it in Kejeik prepared from Ijl, Nawk and Garmut were 5 × 105, 2.3 × 104 and 1.0 × 104 cfu/gm, respectively. The fungi isolated from Kejeik samples were identified as Aspergillus niger, Alternaria, and Penicillium. However, fungi counts in Ijl Kejeik, Nawk Kejeik and Garmut Kejeik were 1.6 × 104, 1.6 × 104 and 1.2 × 104 cfu/gm, respectively. The yeast isolated was identified as Rhodotorula and Cryptococcus laureate, and their counts in Ijl Kejeik and Nawk Kejeik were 0.9 × 104 and 0.9 × 104 cfu/gm, respectively. The halophlic bacteria found in Kejeik samples could be identified as Kocuria rosea and Streptococcus dysgalactiae. 展开更多
关键词 Kejeik MICROBIOLOGICAL Analysis COLIFORM ESCHERICHIA coli Gram Staining
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The Patterns of Blood Groups and Its Association with Blood Donation in Saudi Arabia
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作者 Fahad A. Alateeq Thamer Z. Aldugieman +4 位作者 Yousef Duhaim A. Al-Rashdi Abdul Rahman Ali A. Alsogair Saleh Hadi Alharbi Ibrahim Bin Ahmed Hussain Gadelkarim Ahmed 《Open Journal of Preventive Medicine》 2018年第9期291-300,共10页
Background: Blood groups system has key importance for transfusion safety and clinical practice. Therefore, the objective of the present study was to evaluate the distribution of ABO blood groups and its association w... Background: Blood groups system has key importance for transfusion safety and clinical practice. Therefore, the objective of the present study was to evaluate the distribution of ABO blood groups and its association with blood donation in Saudi Arabia. Methodology: In this study, we collected information regarding blood donation from 715 Saudi volunteers living in the city of Hail, Northern Saudi Arabia. Data about blood donation were obtained from 715 Saudi volunteers living in the city of Hail. Results: The majority of the study population was found with group B+ representing 174 participants, followed by A+, O+, AB+, B-ve, A-ve, AB-ve and O-ve, representing 165, 153, 47, 29, 20, 9, and 7 participants, in this order. Conclusion: The major blood group among Saudi population is group B+ followed by group A+ and O+. Individuals with rare blood groups were less likely to participate in blood donation programs, which necessitate the need for educational programs using motivating factors. 展开更多
关键词 Blood DONATION DONORS SAUDI ARABIA VOLUNTARY DONATION ABO Group
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