检索结果-南通市图书馆

Spinal dural arteriovenous fistula:a comprehensive review of the history,classification systems,management,and prognosis

引用

Chinese Neurosurgical Journal 2024年第1期10卷 48-56页

作者： Ali Alkhaibary Ahoud Alharbi Nada Alnefaie hajar Alammar Alshaymaa M.Arishy Noor Alghanim Yazeed M.Aldhfyan Arwa Albaiahy yahya h.khormi Wael Alshaya Saad AlQahatani Ahmed Aloraidi Ahmed Alkhani Sami Khairy College of Medicine King Saud Bin Abdulaziz University for Health SciencesRiyadhSaudi Arabia King Abdullah International Medical Research Center RiyadhSaudi Arabia Division of Neurosurgery Department of SurgeryKing Abdulaziz Medical CityMinistry of National Guard-Health AffairsRiyadhSaudi Arabia Department of Neurosurgery National Neurosciences InstituteKing Fahad Medical CityRiyadhSaudi Arabia College of Medicine Jazan UniversityJazanSaudi Arabia Department of Neurosurgery King Faisal Specialist Hospital and Research CenterRiyadhSaudi Arabia Department of Surgery Faculty of MedicineJazan UniversityJazanSaudi Arabia

Spinal dural arteriovenous fistulas account for the majority of spinal vascular *** are typically located in the thoracolumbar region and are diagnosed in the middle-aged and elderly *** spinal dural arteriovenous fistulas have been postulated to be acquired,their exact development remains ***,the arteriovenous shunt is situated close to the spinal nerve root,inside the dura mater,where the blood from the radiculomeningeal artery and radicular vein *** history,there have been multiple classification systems of spinal arteriovenous shunts since *** were mainly based on the evolution of diagnostic studies as well as the treatment of these *** classification systems have undergone significant changes over the *** intracranial dural arteriovenous fistula,spinal dural arteriovenous fistula is progressive in *** neurological manifestations,due to venous congestion,tend to be insidious as well as *** include sensory deficits,such as paresthesia,bilateral and/or unilateral radicular pain affecting the lower limbs,and gait *** dural arteriovenous fistulas can be suspected on magnetic resonance imaging/magnetic resonance angiography and confirmed by digital subtraction angiography(DSA).The management includes surgery,endovascular therapy,and in selected cases,*** treatment goal of spinal dural arteriovenous fistula is to halt the progression of the *** prognosis depends on both the duration of symptoms as well as the clinical condition prior to *** present article comprehensively reviews the pathophysiology,changes in classification systems,natural history,clinical manifestations,radiological features,management,and prognosis.

关键词： Connection Endovascular Myelopathy Vascular

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

Thermal Decomposition of Olive-Solid Waste by TGA: Characterization and Devolatilization Kinetics under Nitrogen and Oxygen Atmospheres

引用

Journal of Power and Energy Engineering 2024年第3期12卷 31-47页

作者： yahya h. Khraisha Chemical Engineering Department University of Jordan Amman Jordan

Despite the fact that a few countries in the Mediterranean and the Middle East have limited crude oil reserves, they have abundant biomass feedstocks. For instance, Jordan relies heavily on the importation of natural gas and crude oil for its energy needs;but, by applying thermochemical conversion techniques, leftover olive oil can be used to replace these energy sources. Understanding the chemical, physical, and thermal characteristics of raw materials is essential to obtaining the most out of these conversion processes. Thermogravimetric analysis was used in this study to examine the thermal behavior of olive-solid residue (kernel) at three different heating rates (5, 20 and 40 C/min) in nitrogen and oxygen atmospheres. The initial degradation temperature, the residual weight at 500 and 700˚C and the thermal degradation rate during the devolatilization stage (below 400˚C) were all determined. It was found that in N2 and O2 atmospheres, both the initial degradation temperature and the degradation rate increase with increasing heating rates. As heating rates increase in the N2 atmosphere, the residual weight at 500 or 700˚C decreases slightly, but at low heating rates compared to high heating rates in the O2 atmosphere, it decreases significantly. This suggests that a longer lignin oxidation process is better than a shorter one. Coats and Redfern approach was used to identify the mechanism and activation energy for the devolatilization stage of pyrolysis and oxidation reactions. The process mechanism analysis revealed that the model of first-order and second-order reactions may adequately describe the mechanism of heat degradation of the devolatilization step of olive-solid waste for pyrolysis and oxidation processes, respectively.

关键词： Biomass Olive-Solid Waste Thermogravimetry Pyrolysis Oxidation heating Rates Kinetics

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

Mitigating diabetes-related complications:Empowering metformin with cholecalciferol and taurine supplementation in type 2 diabetic rats

引用

World Journal of Diabetes 2024年第8期15卷 1778-1792页

作者： Mai S Attia Fadwa Ayman Mohamed S Attia Galal yahya Mansour h Zahra Magdi Mohamed Ibrahim Khalil Abdel Aziz A Diab Department of Zoology Faculty of ScienceZagazig 44519Egypt Department of Pharmaceutics Faculty of PharmacyZagazig 44519Egypt Department of Microbiology and Immunology Faculty of PharmacyZagazig UniversityZagazig 44519Egypt Department of Biochemistry Faculty of MedicineZagazig 44519Egypt

BACKGROUND Type 2 diabetes is one of the most prevalent chronic diseases worldwide,significantly impacting patients'quality of *** treatment options like metformin(MET)effectively counteract hyperglycemia but fail to alleviate diabetes-associated complications such as retinopathy,neuropathy,nephropathy,hepatopathy,and cardiovascular *** To propose the supplementation of cholecalciferol(ChO)and taurine(TAU)to enhance MET efficacy in controlling diabetes while minimizing the risk of associated *** The study involved sixty rats,including ten non-diabetic control rats and fifty experimental rats with type 2 diabetes induced by *** experimental rats were further subdivided into positive control and treatment *** four treatment groups were randomly allocated to a single MET treatment or MET combined with supplements either ChO,TAU,or *** Diabetic rats exhibited elevated levels of glucose,insulin,homeostasis Model Assessment of Insulin Resistance(hOMA-IR),glycated hemoglobin percentage,lipid markers,aspartate aminotransferase,and malondialdehyde,along with reduced levels of antioxidant enzymes(catalase and superoxide dismutase).The administration of ChO and TAU supplements alongside MET in diabetic rats led to a noticeable recovery of islet *** antioxidative,anti-inflammatory,and anti-apoptotic properties of the proposed combination therapy significantly ameliorated the aforementioned *** The supplementation of ChO and TAU with MET showed the potential to significantly improve metabolic parameters and protect against diabetic complications through its antioxidative,anti-inflammatory,and antiapoptotic effects.

关键词： Diabetes complications Metformin Cholecalciferol Taurine Glycated hemoglobin% Antioxidant

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

Impact of device resistances in the performance of graphene-based terahertz photodetectors

引用

Frontiers of Optoelectronics 2024年第2期 89-99页

作者： óscar Castelló Sofía M.López Baptista Kenji Watanabe Takashi Taniguchi Enrique Diez Jesús Enrique Velázquez-Pérez yahya M.Meziani José M.Caridad Juan A.Delgado-Notario Department of Applied Physics University of Salamanca Unidad de Excelencia en Luz y Materia Estructurada(LUMES) University of Salamanca Research Center for Electronic and Optical Materials National Institute for Materials Science Research Center for Materials Nanoarchitectonics National Institute for Materials Science Nanotechnology Group USAL–Nanolab University of Salamanca

In recent years, graphene field-effect-transistors(GFETs) have demonstrated an outstanding potential for terahertz(Thz) photodetection due to their fast response and high-sensitivity. Such features are essential to enable emerging Thz applications, including 6G wireless communications, quantum information, bioimaging and security. however, the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device, so-called access or parasitic resistances. In this work, we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFET detectors. Such dual-gate architectures allow us to fine tune(decrease) the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector, respectively. Our results can be well understood by a series resistance model, as shown by the excellent agreement found between the experimental data and theoretical calculations. These findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

An Efficient Text-Independent Speaker Identification Using Feature Fusion and Transformer Model

引用

Computers, Materials & Continua 2023年第5期75卷 4085-4100页

作者： Arfat Ahmad Khan Rashid Jahangir Roobaea Alroobaea Saleh yahya Alyahyan Ahmed h.Almulhi Majed Alsafyani Chitapong Wechtaisong College of Computing Khon Kaen UniversityKhon Kaen40000Thailand Department of Computer Science COMSATS University IslamabadVehari CampusVehari61100Pakistan Department of Computer Science College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Computer Science Community College in DwadmiSharqa UniversityDawadmi17472Saudi Arabia School of Telecommunication Engineering Suranaree University of TechnologyNakhon Ratchasima30000Thailand

Automatic Speaker Identification(ASI)involves the process of distinguishing an audio stream associated with numerous speakers’*** common aspects,such as the framework difference,overlapping of different sound events,and the presence of various sound sources during recording,make the ASI task much more complicated and *** research proposes a deep learning model to improve the accuracy of the ASI system and reduce the model training time under limited computation *** this research,the performance of the transformer model is *** audio features,chromagram,Mel-spectrogram,tonnetz,Mel-Frequency Cepstral Coefficients(MFCCs),delta MFCCs,delta-delta MFCCs and spectral contrast,are extracted from the ELSDSR,CSTRVCTK,and Ar-DAD,*** evaluation of various experiments demonstrates that the best performance was achieved by the proposed transformer model using seven audio features on all *** ELSDSR,CSTRVCTK,and Ar-DAD,the highest attained accuracies are 0.99,0.97,and 0.99,*** experimental results reveal that the proposed technique can achieve the best performance for ASI problems.

关键词： Speaker identification signal processing Arabic deep learning transformer

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

Energetic Study on Jordanian Olive Cake and Woody Biomass Materials

引用

Journal of Power and Energy Engineering 2022年第2期10卷 1-13页

作者： yahya h. Khraisha Chemical Engineering Department University of Jordan Amman Jordan

In this work, the potential for energy production in Jordan was explored using four distinct types of biomass samples (olive cakes, woods). The proximate analysis, oil content, and higher heating value were all determined experimentally and compared to other biomass previously published in the literature. The findings appear to be similar to other biomass materials utilized as solid biofuel feed-stock materials. Olive cake and wood samples have lower calorific values than anthracite coal, ranging from 25% to 40% lower. According to the results of this study, olive cake samples had the highest oil extractive content (14.5 wt%), followed by pine and beech woody samples with 8.9 wt% and 3.1 wt%, respectively. The calorific values of the biomass samples tested ranged from 18 to 22 MJ/kg, making them suitable for use as fuel. Moreover, the high volatile matter content (78% to 93%) was appropriate for chemical energy conversion by gasification or combustion process. Jordan can create roughly 8000 tons of pomace oil per year from the waste solid olive cake, based on existing results. Furthermore, the olive cake’s energy potential in Jordan is estimated to be 38 MW based on the higher heating value of the tested samples and the annual quantity of this resource. In the meantime, due to limited annual production, Jordanian firewood has the modest energy potential (2.4 MW).

关键词： Biomass Olive Cake Proximate Analysis Calorific Values Soxhlet Ex-traction

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

Identification Schemes for Unmanned Excavator Arm Parameters

引用

International Journal of Automation and computing 2008年第2期5卷 185-192页

作者： yahya h.Zweiri Department of Mechanical Engineering Mu'tah University

Parameter identification is a key requirement in the field of automated control of unmanned excavators （UEs）. Furthermore, the UE operates in unstructured, often hazardous environments, and requires a robust parameter identification scheme for field applications. This paper presents the results of a research study on parameter identification for UE. Three identification methods, the Newton-Raphson method, the generalized Newton method, and the least squares method are used and compared for prediction accuracy, robustness to noise and computational speed. The techniques are used to identify the link parameters （mass, inertia, and length） and friction coefficients of the full-scale UE. Using experimental data from a full-scale field UE, the values of link parameters and the friction coefficient are identified. Some of the identified parameters are compared with measured physical values. Furthermore, the joint torques and positions computed by the proposed model using the identified parameters are validated against measured data. The comparison shows that both the Newton-Raphson method and the generalized Newton method are better in terms of prediction accuracy. The Newton-Raphson method is computationally efficient and has potential for real time application, but the generalized Newton method is slightly more robust to measurement noise. The experimental data were obtained in collaboration with QinetiQ Ltd.

关键词： Parameters identification complex dynamic systems Newton-Raphson method generalized Newton method least squares method full-scale validation

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

Effects of Increasing Tungsten on Structural,Elastic and Optical Properties of xWO_3-(40-x)Ag_2O-60Te_2O Glass System

引用

Journal of Materials Science & Technology 2015年第1期31卷 83-90页

作者： MM.Umair A.K.yahya M.K.halimah h.A.A.Sidek School of Physics and Materials Studies Universiti Teknologi MARA Department of Physics Faculty of ScienceUniversiti Putra Malaysia

Ternary teiiurite glasses with composition of xWO3（40-x）Ag2O-60TeO2（x=0-40 mol%） have been prepared by melt-quenching *** and optical properties of the glass system were obtained by ultrasonic velocity measurements and UV-vis spectroscopy,respectively,while structural investigation was carried out by using Raman *** longitudinal and shear velocities,vLand vsshowed large increase at x from 0 to 20 mol%before decrease with further addition of *** longitudinal modulus CLand shear modulus μ bulk modulus KeYoung’s modulus Vand Debye temperature θDshowed similar behaviors to both *** large increase of the elastic moduli at x from 0 to 20 mol%is suggested to be due to the increase in WO6octahedral unit structure indicating the increase of bridging oxygen（BO） and formation of stronger Te-O-W bonds compared to Te-O-Te *** the other hand,forx> 20 mol%,the decrease in the elastic moduli was due to the increase of non-bridging oxygen（NBO） as a result of formation of WO4tetrahedral via breaking Te-O-W *** analysis by using bulk compression and ring deformation models showed a slight decrease in the ratio of ideal bulk modulus Kbcto the experimental bulk modulus Keand average atomic ring size,/ for× 20 mol%.Our analysis also indicates that limited ring deformation took place and the main compression mechanism in this glass system was mainly ideal isotropic *** the other hand,optical band gap Eoptshowed small variation for x=0-20 mol%but decreased upon higher WO3content while refractive index n showed the opposite *** optical behavior is suggested to be related to the changes in cross link density and NBO concentration in the glass system.

关键词： Elastic moduli Optical absorption Raman spectrosco

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

Catalytic effect of SrTiO_3 on the hydrogen storage behaviour of Mgh_2

引用

Journal of Energy Chemistry 2019年第1期28卷 46-53页

作者： M.S.yahya M.Ismail School of Ocean Engineering University Malaysia Terengganu

The effects of Sr TiO_3 on the hydrogen storage properties of Mgh_2 have been studied for the first *** onset dehydrogenation temperature of the Mgh_2-10 wt% SrTiO_3 is found to be 275 ℃, which is 55 ℃ lower as compared to the as-milled Mgh_2. The composite is able to absorb 4.3 wt% of hydrogen in 60 min instead of 1.1 wt% for the as-milled Mg h_2. Meanwhile, the composite is able to release 5.3 wt% of hydrogen in 17 min compared to 1.9 wt% by the as-milled Mg h_2 at 320 ℃. The calculated Eaof the Mg h_2-10 wt% SrTiO_3 is 109 k J/mol, which is 26.3 kJ/mol lower than the calculated Eaof the as-milled Mgh_2. The Sr TiO_3 is not decomposed during the ball milling and the re/dehydrogenation processes. The catalytic effect shown by the SrTiO_3 is owing to its ability to change the physical structure of the Mgh_2 particles during the ball milling process.

关键词： hydrogen storage Magnesium hydride Catalytic effect Sorption properties

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

Influence of nickel addition on the microstructure and mechanical properties of Al2O3–5vol%ZrO2 ceramic composites prepared via precipitation method

引用

International Journal of Minerals,Metallurgy and Materials 2019年第7期26卷 908-914页

作者： Betül Kafkasl?o?lu Y?ld?z hüseyin Y?lmaz yahya Kemal Tür Department of Materials Science and Engineering Gebze Technical University

The aim of this work was to investigate the microstructure and mechanical properties of 1vol%-Ni-added yttria-stabilized zirconia (YSZ) toughened alumina composites. First, Ni powders were heterogeneously precipitated in an alumina–zirconia powder mixture suspended in water;the prepared specimens were then pressureless sintered at 1550°C/2 h in a 90vol%Ar/10vol% h2 atmosphere. The structure of phases and microstructure of the composites were characterized by X-ray diffraction and scanning electron microscopy, respectively. Mechanical characterization of the specimens was carried out through Vickers hardness, Vickers indentation toughness, and three-point flexural bending tests. The fine Ni particles were homogeneously dispersed throughout the alumina matrix because of the employed processing method. Furthermore, hardness and toughness values were found to increase by 8% and 50%, respectively, with Ni addition, whereas the relative densities and flexural strength values were found to remain unchanged.

关键词： alumina zirconia ceramic matrix microstructure hardness strength toughness

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

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：