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Transthoracic echocardiographic and clinical predictors in first versus recurrent ischemic strokes

World Journal of Cardiovascular Diseases 2014年第2期4卷 70-76页

作者： Yasser Bahnacy amr abo koora Hamed Dawoud Wafa Rashed Ali Sadek Cardiology Division Chest Diseases Hospital Ferwania Kuwait Cardiology Division Department of Medicine Mubarak Al-Kabeer Hospital Hawally Kuwait Neurology Division Department of Medicine Mubarak Al-Kabeer Hospita Hawally Kuwait Public Health Department Ministry of Health Ferwania Kuwait

Recurrent strokes are more likely to be disabling or fatal than first ever strokes. The aim of the study is to evaluate transthoracic echocardiographic (TTE) and clinical predictors in patients with first versus those with recurrent ischemic strokes. A prospective observational comparative study of 217 patients admitted with ischemic strokes who were in sinus rhythm. Two groups of patients were simultaneously enrolled. The first group was 110 patients with first ischemic stroke and the second was 107 patients with recurrent ischemic stroke. TTE was done for all patients. Both echocardiographic and clinical risk factors were compared between both groups. Logistic regression analysis identified predictors for recurrent strokes. Among clinical risk factors hypertension, hyperlipidemia, family history of atherosclerotic vascular disease, prior coronary artery disease, peripheral vascular disease, and chronic kidney disease were significantly higher in recurrent stroke group. Multivariate logistic analysis identified age (OR, 1.03;95% CI, 1.01 - 1.07), hypertension (OR, 2.25;95% CI, 1.03 - 4.92), and hyperlipidemia (OR, 2.73;95% CI, 1.40 - 5.35), as predictors for recurrent ischemic strokes. Left ventricular diastolic dysfunction, left ventricular hypertrophy (LVH) and aortic sclerosis were significantly more common in the recurrent stroke group compared to the first stroke group. However, in multivariate logistic analysis only LVH (OR, 3.50;95% CI, 1.69 - 7.23), was identified as a predictor for recurrent strokes. Older age, hypertension, hyperlipidemia and left ventricular hypertrophy are significant predictors of recurrent ischemic strokes in patients with sinus rhythm. Those patients need more aggressive lipid lowering therapy and optimal blood pressure control.

关键词： Echocardiography Risk Factors Predictors Ischemic Stroke

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A numerical investigation into the effect of altering compression ratio, injection timing, and injection duration on the performance of a diesel engine fuelled with diesel-biodiesel-butanol blend

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Clean Energy 2024年第5期8卷 73-96页

作者： Abdulkarim Youssef amr Ibrahim Mechanical Engineering Department Beirut Arab University115020 BeirutLebanon Mechanical Engineering Department Alexandria UniversityAlex 21544Egypt

Using renewable fuels for diesel engines can reduce both air pollution and dependence on fossil fuels.A computer simulation was constructed to predict the performance,combustion characteristics,and NOx emissions of a diesel engine fuelled with diesel-biodiesel-butanol *** simulation was validated by comparing the modelling results against experimental data and a good agreement between the results was *** fuels used for the validation were diesel(B0),biodiesel(B100),diesel-biodiesel blend(B50),and two diesel-biodiesel-butanol blends with 45%diesel-45%biodiesel-10%butanol(Bu10)and 40%diesel-40%biodiesel-20%butanol(Bu20)by *** results showed that the addition of butanol reduced NOx emissions but deteriorated the engine *** aim of the current work was the numerical optimization of the different parameters to enhance the engine performance while using butanol to decrease NOx *** engine compression ratio(CR)varied from 14 to 24,in increments of *** injection timing(IT)was reduced from 30°before top dead centre(bTDC)to 5°bTDC in increments of 5°.Also,the fuel injection duration(IDur)was extended from 20°to 50°in increments of 10°.Results showed that the increase in the CR improved engine performance for the two investigated fuels,Bu10 and *** maximum engine brake power(BP),thermal efficiency(BTE),and minimum brake-specific fuel consumption(BSFC)of 1.46 kW,32.3%,and 0.273 kg/kWh respectively,were obtained when the Bu10 fuel was injected under the optimum conditions of 24 CR,15°bTDC IT,and 40°*** these optimum conditions,the BP,BTE,and BSFC improved by 3%-3.5%for Bu10 and Bu20 fuel blends compared with the base engine conditions of a CR of 22,30°IDur,and 10°bTDC *** heat release rate during the premixed phase increased when the IT was advanced,while the mixing-controlled combustion phase was enhanced when the IT was *** emissions increased with increasing CR,while both an increase in IDur at con

关键词： compression ratio injection timing injection duration butanol biodiesel diesel

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Node Sociability Based Intelligent Routing for Post-Disaster Emergency Networks

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China Communications 2024年第8期21卷 104-114页

作者： Li Jiameng Xiong Xuanrui Liu Min amr Tolba School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China Graduate School of Information Production and SystemsWaseda UniversityFukuoka 808-0135Japan School of Communications and Information Engineering Chongqing College of Mobile CommunicationChongqing 401520China Computer Science Department Community CollegeKing Saud UniversityRiyadh 11437Saudi Arabia

In a post-disaster environment characterized by frequent interruptions in communication links,traditional wireless communication networks are *** the“store-carry-forward”mechanism characteristic of Delay Tolerant Networks(DTNs)can transmit data from Internet of things devices to more reliable base stations or data centres,it also suffers from inefficient data transmission and excessive transmission *** address these challenges,we propose an intelligent routing strategy based on node sociability for post-disaster emergency network ***,we introduce an intelligent routing strategy based on node intimacy,which selects more suitable relay nodes and assigns the corresponding number of message copies based on comprehensive utility ***,we present an intelligent routing strategy based on geographical location of nodes to forward message replicas secondarily based on transmission utility ***,experiments demonstrate the effectiveness of our proposed algorithm in terms of message delivery rate,network cost ratio and average transmission delay.

关键词： delay tolerant networks Internet of things node sociability routing strategy

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Asphaltene onset pressure measurement and calculation techniques:A review

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Petroleum 2024年第2期10卷 191-201页

作者： Sherif Fakher amr Yousef Aseel Al-Sakkaf Shams Eldakar Petroleum and Energy Engineering The American University in CairoCairoEgyp

Asphaltene precipitation can result in several production,operational,and transportation problems during oil *** asphaltene precipitates and deposits,it can reduce reservoir permeability,damage wellbore equipment,and plug the *** is therefore extremely important to evaluate the conditions at which asphaltene precipitation occurs;this is referred to as the asphaltene onset *** onset pressure has been measured using many different experimental *** have also been many attempts along the years to predict asphaltene onset pressure using mathematical correlations and *** research provides an up-to-date comprehensive review of the methods by which asphaltene onset pressure can be measured using laboratory experiments and mathematical *** research explains the main mechanisms of all the laboratory experiments to measure asphaltene onset pressure under static conditions and how to conduct them and highlights the advantages and limitations of each *** research also provides a summary of the commonly used mathematical models to quantify asphaltene onset pressure directly and indirectly.

关键词： Asphaltene onset measurement

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Improved combustion stability of biogas at different CO_(2) concentrations using inhomogeneous partially premixed stratified flames

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Global Energy Interconnection 2024年第4期7卷 486-502页

作者： Mohy Saad Mansour Maged Kiriakos Lili Hao Mohamed amr Serag-Eldin Mechanical Power Engineering Department Cairo University1 Gamaa StreetCairo Governorate 12613Egypt Mechanical Engineering Department The American University in CairoAUC AveCairo Governorate 11835Egypt College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816P.R.China

Biogas is a renewable and clean energy source that plays an important role in the current environment of lowcarbon *** high-content CO_(2) in biogas can be separated,transformed,and utilized,it not only realizes high-value utilization of biogas but also promotes carbon reduction in the biogas *** improve the combustion stability of biogas,an inhomogeneous,partially premixed stratified(IPPS)combustion model was adopted in this *** thermal flame structure and stability were investigated for a wide range of mixture inhomogeneities,turbulence levels,CO_(2) concentrations,air-to-fuel velocity ratios,and combustion energies in a concentric flow slot burner(CFSB).A fine-wire thermocouple is used to resolve the thermal flame *** flame size was reduced by increasing the CO_(2) concentration and the flames became lighter *** flame temperature also decreased with increase in CO_(2) *** stability was reduced by increasing the CO_(2) ***,at a certain level of mixture inhomogeneity,the concentration of CO_(2) in the IPPS mode did not affect the ***,the IPPS mode of combustion should be suitable for the combustion and stabilization of *** should support the design of highly stabilized biogas turbulent flames independent of CO_(2) *** data show that the lower stability conditions are partially due to the change in fuel combustion energy,which is characterized by the Wobbe index(WI).In addition,at a certain level of mixture inhomogeneity,the effect of the WI on flame stability becomes dominant.

关键词： Biogas Renewable energy Effect of CO_(2) Combustion stability Burner design Renewable fuels Partial premixed

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Efficient energy harvesting from PV Panel with reinforced hydrophilic nano-materials for eco-buildings

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Energy and Built Environment 2024年第3期5卷 393-403页

作者： Ahmed Elnozahy Heba Abd-Elbary Farag K.abo-Elyousr Department of Electrical Engineering Faculty of EngineeringAssiut UniversityAssiut 71516Egypt

The main target of this research is to allow solar PV to contribute economically to an on-grid energy-efficient building where the dust accumulation is a significant ***-cleaning coatings such as hydrophobic or hy-drophilic materials have recently been introduced to reduce dust deposition on building-integrated PV(BIPV)*** hydrophilic Nano-coated material is examined as a solution to decrease the impact of the dust on the BIPV panels and harvest more solar *** impartial comparison of the BIPV panels performance under natu-ral dust conditions,manual cleaning,and hydrophilic nanomaterial coating is *** an exhaustive and qualitative experimental analysis,the anti-reflection and anti-static properties of the utilized Nano-coated material are *** experimental results show that the hydrophilic Nano-coated material significantly improves the gathered maximum output power by 18%compared to the manually wiped *** calculated efficiencies of the Nano-coated,manual cleaning,and dusty panels are 11%,9%,and 6%,respectively,which highlights the futureproofing of the Nano-coated solar *** to the dusty panels,the ecological and economical results show that the BIPV carbon emissions are desirably dropped by 11%while using Nano-coated PV panels and the payback period is reduced to 3.9 years,which is approximately 12.8%faster.

关键词： Hydrophilic Self-cleaning BIPV panels Nano-coating Techno-economic

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Numerical Treatments for Crossover Cancer Model of Hybrid Variable-Order Fractional Derivatives

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1619-1645页

作者： Nasser Sweilam Seham Al-Mekhlafi Aya Ahmed Ahoud Alsheri Emad abo-Eldahab Mathematics Department Faculty of ScienceCairo UniversityGiza12613Egypt Mathematics Department Faculty of EducationSana’a UniversitySana’a1247Yemen Mathematics Department Faculty of ScienceHelwan UniversityCairo11795Egypt Department of Mathematics College of ScienceUniversity of BishaAl Namas67398-5644Saudi Arabia

In this paper,two crossover hybrid variable-order derivatives of the cancer model are ***ünwald-Letnikov approximation is used to approximate the hybrid fractional and variable-order fractional *** existence,uniqueness,and stability of the proposed model are *** Bashfourth’s fifth-step method with a hybrid variable-order fractional operator is developed to study the proposed *** studies with generalized fifth-order Runge-Kutta method are *** examples and comparative studies to verify the applicability of the used methods and to demonstrate the simplicity of these approximations are *** have showcased the efficiency of the proposed method and garnered robust empirical support for our theoretical findings.

关键词： Cancer diseases hybrid variable-order fractional derivatives adams bashfourth fifth step generalized fifth order Runge-Kutta method

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Advancing sandstone reservoir compressibility prediction:A correlation-driven methodology

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Petroleum Research 2024年第2期9卷 273-279页

作者： Tarek Ganat Meftah Hrairi amr Badawy Vahid Khosravi Mohammed Abdalla Department of Petroleum Chemical Engineering Sultan Qaboos UniversityP.O.Box 50Al-Khod123MuscatOman Department of Mechanical and Aerospace Engineering International Islamic University MalaysiaP.O.Box 1050728Kuala LumpurMalaysia Reservoir Engineering Section Petronas Carigali SDN BHDP.O.Box 10500088Kuala LumpurMalaysia Department of Chemical and Petroleum Engineering Faculty of EngineeringTechnologyand Built EnvironmentUCSI University56000Kuala LumpurMalaysia Chemical&Petroleum Engineering United Arab Emirates UniversityP.O.Box No.15551Al AinUAE

This study presents a correlation-based approach for predicting the compressibility of sandstone reservoir *** study proposes a matrix of new empirical equations that significantly improve the precision of measuring the pore volume compressibility,with the most optimal fit of results based on a cubic polynomial *** accuracy of the calculations was validated through comparison with actual data using root mean square method,and the suggested correlations significantly enhance the precise prediction of rock compressibility in sandstone *** this study,the source of data collection is consolidated and unconsolidated sandstone from East Asia offshore ***,variations in compressibility with net overburden pressure over the course of the field's lifespan have been *** results demonstrate the application of regression analysis in establishing a network of linkages between independent and dependent *** proposed correlations for consolidated and unconsolidated sandstones offer a remarkable improvement in the accurate calculation of rock compressibility compared to traditional laboratory procedures,with an average error of 2.5%compared to 5-10%for laboratory *** approach of this study offers a cost-effective and time-efficient alternative to remarkedly enhance the overall performance of sandstone reservoirs in the oil and gas industry.

关键词： Compressibility Consolidated and unconsolidated sandstone Rock properties Rock mechanics

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Assessment of plant diversity of endemic species of the Saharo-Arabian region in Egypt

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Journal of Arid Land 2024年第7期16卷 1000-1021,I0002-I0044页

作者： Asmaa S abo HATAB Yassin M AL-SODANY Kamal H SHALTOUT Soliman A HAROUN Mohamed M EL-KHALAFY Botany and Microbiology Department Faculty of ScienceKafrelsheikh UniversityKafrelsheikh 33511Egypt Botany Department Faculty of ScienceTanta UniversityTanta 31527Egypt

Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, Syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the Sudano-Zambezian region belonging to the Paleotropical Kingdom and the Mediterranean and Irano-Turanian regions included in the Holarctic Kingdom, share a large portion of their flora with the Saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the Saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the Saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. Hence, a preliminary list of 429 Saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the Saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, South Sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of Sinai Peninsula, 53 taxa). Sahara regional subzone(SS1) distributes all the 126 endemic species, Arabian regional subzone(SS2) owns 79 taxa, and Nubo-Sindian subzone(SS3) distributes only 14 endemics. Seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINSPAN) to the Saharo-Arabian endemic sp

关键词： endemism phytogeographical regions Saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINSPAN)

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SwinVid:Enhancing Video Object Detection Using Swin Transformer

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Computer Systems Science & Engineering 2024年第2期48卷 305-320页

作者： Abdelrahman Maharek amr abozeid Rasha Orban Kamal ElDahshan Computer Science Department Faculty of Artificial Intelligence and InformaticsBenhaEgypt Mathematics Department Faculty of SciencesAl-Azhar UniversityCairoEgypt Department of Computer Science College of Science and Arts in QurayyatJouf UniversitySakakaSaudi Arabia

What causes object detection in video to be less accurate than it is in still images?Because some video frames have degraded in appearance from fast movement,out-of-focus camera shots,and changes in *** reasons have made video object detection(VID)a growing area of research in recent *** object detection can be used for various healthcare applications,such as detecting and tracking tumors in medical imaging,monitoring the movement of patients in hospitals and long-term care facilities,and analyzing videos of surgeries to improve technique and ***,it can be used in telemedicine to help diagnose and monitor patients *** VID techniques are based on recurrent neural networks or optical flow for feature aggregation to produce reliable features which can be used for *** of those methods aggregate features on the full-sequence level or from nearby *** create feature maps,existing VID techniques frequently use Convolutional Neural Networks(CNNs)as the backbone *** the other hand,Vision Transformers have outperformed CNNs in various vision tasks,including object detection in still images and image *** propose in this research to use Swin-Transformer,a state-of-the-art Vision Transformer,as an alternative to CNN-based backbone networks for object detection in *** proposed architecture enhances the accuracy of existing VID *** ImageNet VID and EPIC KITCHENS datasets are used to evaluate the suggested *** have demonstrated that our proposed method is efficient by achieving 84.3%mean average precision(mAP)on ImageNet VID using less memory in comparison to other leading VID *** source code is available on the website https://***/amaharek/SwinVid.

关键词： Video object detection vision transformers convolutional neural networks deep learning

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