检索结果-南通市图书馆

Diagnostic value of dobutamine stress Doppler tissue imaging in diabetic patients with suspected coronary artery disease

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Cardiovascular Diseases 2011年第1期1卷 1-12页

作者： Mohamed Fahmy Elnoamany Hala Mahfouz Badran Tarek Salah Khalil abdalla mostafa kamal Amany Ragab Serag Rehab Ebraheem Yaseen 不详

Background: Coronary artery disease (CAD) is often silent in diabetic patients, and it is typically in ad-vanced stages of development by the time it manifests. Various forms of stress testing have been investigated to detect obstructive CAD in diabetes mellitus. Ob-jectives: To assess the diagnostic value of dobutamine stress pulsed-wave Doppler tissue imaging (DTI) compared with standard wall motion analysis in de-tection of myocardial ischemia in diabetic patients with suspected CAD. Methods: The study comprised 46 diabetic patients with suspected CAD underwent dobutamine stress echocardiography (DSE) with DTI within 4 weeks before coronary angiography(CA). Dobutamine infusion started at 5 μ/kg/min and in-creased up to 40 μ/kg/min with additional atropine during submaximal heart rate responses. In addition to wall-motion score index (WMSI) analysis, pulsed- wave DTI examination of basal and mid segments of posteroseptal, lateral, anterior, inferior and antero- septal walls was performed. Myocardial velocities were measured at rest in the apical 4, 3 and 2-cham- ber views. The measurements were repeated at low dose (10 - 15 μ/kg/min) and at peak stress (40 μ/kg/min). DTI measurements included peak systolic velocity (S), peak early diastolic velocity (E) and peak late diastolic velocity (A) and the results were com-pared to WMSI analysis. Patients were classified into two groups according to CA results;group (I) di-abetics with positive CA (n = 27) and group (II) di-abetics with negative CA (n = 19). Results: There was no significant difference between the two groups in duration of diabetes, global WMSI at rest or the ? changes (stress-rest/rest) of WMSI (P > 0.05). Global S and global E were significantly lower in group I compared to group II at peak stress (11.3 ± 3.7 cm/sec vs. 14.5 ± 2.2 cm/sec, p < 0.01) and (11.3 ± 1.6 cm/sec vs. 13.1 ± 2.1 cm/sec, p < 0.01) respectively. The cutoff points for global S and global E to detect obstructive CAD in diabetics were

关键词： Doppler Tissue Imaging Dobutamine Stress Diabetes Mellitus

Multifunction Battery Energy Storage System for Distribution Networks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy Engineering 2022年第2期119卷 569-589页

作者： Omar H.abdalla Gamal Abdel-Salam Azza A.A.mostafa Department of Electrical Power&Machines Helwan UniversityCairoEgypt Technical Affairs Sectors South Cairo Electricity Distribution CompanyCairoEgypt Department of Energy Efficiency and Renewables Egyptian Electric Utility and Customer Protection Regulatory AgencyCairoEgypt

Battery Energy Storage System(BESS)is one of the potential solutions to increase energy system flexibility,as BESS is well suited to solve many challenges in transmission and distribution *** of distribution network’s challenges,which affect network performance,are:(i)Load disconnection or technical constraints violation,which may happen during reconfiguration after fault,(ii)Unpredictable power generation change due to Photovoltaic(PV)penetration,(iii)Undesirable PV reverse power,and(iv)Low Load Factor(LF)which may affect electricity *** this paper,the BESS is used to support distribution networks in reconfiguration after a fault,increasing Photovoltaic(PV)penetration,cutting peak load,and loading valley *** paper presents a methodology for BESS optimal locations and sizing considering technical constraints during reconfiguration after a fault and PV power generation *** determining themaximumpower generation change due to PV,actual power registration of connected PV plants in South Cairo Electricity Distribution Company(SCEDC)was considered for a *** addition,the paper provides a procedure for distribution network operator to employ the proposed BESS to perform multi functions such as:the ability to absorb PV power surplus,cut peak load and fill load valley for improving network’s *** methodology is applied to a modified IEEE 37-node and a real network part consisting of 158 nodes in SCEDC *** simulation studies are performed using the DIgSILENT PowerFactory software andDPL programming *** Mixed Integer Linear Programming optimization technique(MILP)in MATLAB is employed to choose the best locations and sizing of BESS.

关键词： Battery energy storage system photovoltaic penetration peak load reduction valley filling MILP optimization

Nanothermite colloids: A new prospective for enhanced performance

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2019年第3期15卷 319-325页

作者： M. Gaber Zaky Ahmed M. abdalla Rakesh P. Sahu Ishwar K. Puri mostafa Radwan Sherif Elbasuney School of Chemical Engineering Military Technical College Kobry Elkoba Cairo Egypt Department of Engineering Physics and Department of Mechanical Engineering McMaster University 1280 Main Street West Hamilton Ontario L8S 4L7 Canada Department of Mechanical Engineering McMaster University 1280 Main Street West Hamilton Ontario L8S 4L7 Canada British University in Egypt Elshorouk City Cairo Egypt

Nanothermites (metal oxide/metal) can offer tremendously exothermic self sustained reactions. CuO is one of the most effective oxidizers for naonothermite applications. This study reports on two prospectives for the manufacture of CuO nanoparticles. Colloidal CuO particles of 15 nm particle size were developed using hydrothermal synthesis technique. Multiwalled carbon nanotubes (MWCNTs) with surface are 700m2/g was employed as a substrate for synthesis of CuO-coated MWCNTs using electroless plating. On the other hand, aluminium particles with combustion heat of 32000 J/g is of interest as high energy density material. The impact of stoichiometric nanothermite particles (CuO/Al & Cuo-coated MWCNTs/Al) on shock wave strength of Al/TNT nanocomposite was evaluated using ballistic mortar test. While CuO-coated MWCNTs decreased the shock wave strength by 15%;colloidal CuO enhanced the shock wave strength by 30%. The superior performance of colloidal CuO particles was correlated to their steric stabilization with employed organic solvent. This is the first time ever to report on fabrication, isolation, and integration of stablilized colloidal nanothermite particles into energetic matrix where intimate mixing between oxidizer and metal fuel could be achieved.

关键词： Hydrothermal synthesis Nanoparticles Carbon nanotubes Nanothermites Energetic materials

Achievements and trends of solid oxide fuel cells in clean energy field: a perspective review

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

Frontiers in Energy 2020年第2期14卷 359-382页

作者： abdalla M.abdalla Shahzad HOSSAIN Pg MohdIskandr PETRA mostafa GHASEMI Abul K.AZAD Faculty of Integrated Technologies Universiti Brunei DarussalamJalanTungku LinkGadong BE 1410Brunei Darussalam Mechanical Engineering Department Faculty of EngineeringSuez Canal UniversityIsmailia 41522Egypt Institute of Nuclear Science and Technology Bangladesh Atomic Energy CommissionGPO Box No 3787Dhaka 1000Bangladesh Petroleum Engineering Department Universiti Teknologi PETRONASSeri Iskandar31750 TronohPerakMalaysia

The main concerns in the world today,especially in the energy field,are subjected to clean,efficient,and durable sources of *** three aspects are the main goals that scientist are paying attention ***,the various types of energy resources include fossil and sustainable ones,but still some challenges are chasing these kinds from energy conversion,storage,and ***,the most reliable and considered energy resource nowadays is the utilized one which is as highly efficient,clean,and everlasting as ***,in this review,an attempt is made to highlight one of the promising types as a clean and efficient energy *** oxide fuel cell(SOFC)is the most efficient type of the fuel cell types involved with hydrogen and hydrocarbon-based fuels,especially when it works with combined heat and power(CHP).The importance of this type is due to its nature of work as conversion tool from chemical to electrical for generation of power without noise,pollution,and can be safely handled.

关键词： solid oxide fuel cells(SOFCs) clean energy design micro-scale nano-scale performance

Ion dynamics associated with substorm dipolarization fronts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2014年第10期57卷 2543-2551页

作者： FU Song Maha ASHOUR-abdalla DENG XiaoHua mostafa EL-ALAOUI ZHOU Meng Robert L RICHARD Raymond J WALKER YUAN ZhiGang School of Electronic and Information Wuhan University Institute of Geophysics and Planetary Physics University of California Department of Physics and Astronomy University of California Institute of Space Science and Technology Nanchang University Department of Earth Planetary and Space Sciences University of California National Science Foundation

We report where and how ions are accelerated in the proximity of earthward propagating dipolarization fronts （DFs） in the magnetotail during a magnetospheric substorm on February 15, 2008. Two DFs were observed by multiple THEMIS space- craft in the near-Earth magnetotail （-10 Re）. We studied the ion dynamics associated with these DFs by comparing observed results with large scale kinetic （LSK） simulation results. The LSK simulation reproduced the sudden ion energy flux enhance- ment concurrent with the arrival of the DF at the satellite locations. We found that ions can be accelerated to more than 100 keV energy at the DF. These ions were initially non-adiabatically accelerated near magnetic reconnection site and then still non-adiabatically accelerated at the DF structure.

关键词： dipolarization front particle simulation ion acceleration

Active Aerothermoelastic Control of Hypersonic Double-wedge Lifting Surface

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

Chinese Journal of Aeronautics 2008年第1期21卷 8-18页

作者： Laith K Abbas 陈前 Piergiovanni Marzocca Gürdal Zafer abdalla mostafa 南京航空航天大学克拉克生大学代夫特科技大学

Designing re-entry space vehicles and high-speed aircraft requires special attention to the nonlinear thermoelastic and aerodynamic instability of their structural components. The thermal effects are important since temperature environment brings dramatic influences on the static and dynamic behaviors of flight structures in supersonic/hypersonic regimes and is likely to cause instability, catastrophic failure and oscillations resulting in structural failure due to fatigue. In order to understand the dynamic behaviors of these ＂hot＂ structures, a double-wedge lifting surface with combining freeplay and cubic structural nonlinearities in both plunging and pitching degrees-of-freedom operating in supersonic/hypersonic flight speed regimes has been analyzed. A third order piston theory aerodynamic is used to estimate the applied nonlinear unsteady aerodynamic loads. Also considered is the loss of torsional stiffness that may be incurred by lifting surfaces subject to axial stresses induced by aerodynamic heating. The aerodynamic heating effects are estimated based on the adiabatic wall temperature due to high speed airstreams. As a recently emerging technology, the active aerothermoelastic control is aimed at providing solutions to a large number of problems involving the aeronautical/aerospace flight vehicle structures. To prevent such damaging phenomena from occurring, an application of linear and nonlinear active control methods on both flutter boundary and post-flutter behavior has been fulfilled. In this paper, modeling issues as well as numerical simulation have been presented and pertinent conclusions outlined. It is evidenced that a serious loss of torsional stiffness may induce the dynamic instability; however active control can be used to expand the flutter boundary and convert unstable limit cycle oscillations （LCO） into the stable LCO and/or to shift the transition between these two states toward higher flight Mach numbers.

关键词： active control aerothermoelastic analysis freeplay hypersonic speed

Predictors for Metachronous Metastases in Early Breast Cancer: A Single Institution Study

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

Advances in Breast Cancer Research 2021年第3期10卷 87-99页

作者： Haytham Mahmoud Awad Fayed Mohamed Ali abdalla Billel Galal mostafa Abouelnagah Gehan A. Khedr Surgical Oncology Department Alexandria Faculty of Medicine Alexandria University Alexandria Egypt Clinical Oncology Department Alexandria Faculty of Medicine Alexandria University Alexandria Egypt

Background: Breast cancer (BC) is considered the most common women cancer worldwide. The main clinicopathological prognostic factors are tumor size, lymph node status and estrogen/progesterone (ER/PR) receptor status. In addition, some factors are both prognostic and predictive as ER/PR receptors and HER2/neu overexpression. Axillary lymph node status is the most important prognostic factor for breast cancer. Node negative breast cancer patients had the best 5-year overall survival (OS) of 82.8% compared to 73%, 45.7%, and 28.4% for patients with 1 - 3, 4 - 12, and ≥13 positive nodes, respectively. The aim of this study was to determine the association between different clinicopathological features and development of metastasis in a group of Egyptian women with early breast cancer, also, to assess patients’ Relapse-free survival (DFS) and OS and their correlation with different clinicopathological features. Patients and Methods: We retrospectively reviewed the files of breast cancer patients who were treated and <

关键词： Breast Cancer Metastasis Relapse Free Survival Overall Survival

Urinary Continence after Orthotopic Detubularized Ileocaecal Pouch Versus Ileal Neobladder:Does it Differ?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Modern Oncology Research 2018年第5期4卷 1-4页

作者： abdalla El Azab Sameh Kotb Amro mostafa Ahmed Mahmoud Shouman Mohamed Salama National cancer institute Cairo universityCairoEgypt Urology Department Kasr Al-Ainy HospitalsCairo UniversityCairoEgypt

Objective:To compare both techniques of detubularized ileocaecal and ileal neobladder post radical cystectomy with regards to functional results in the form of continence(day and night)with the use of urodynamics(for assessment of voiding volume and pouch capacity).Methods:This is a prospective randomized clinical trial that was done at the National Cancer Institute,Cairo University from August 2016 and January ***-two patients presented with muscle invasive urinary bladder cancer and no history of urinary incontinence or urethral stricture were included in this *** patients underwent preoperative cystoscopic *** cystectomy was done,and patients were divided into two groups according to the type of *** A included 31 patients with orthotopoic detubularized ileal neobladder and group B included 31 patients with orthotopic detubularized ileocaecal *** studies were done to 27 patients in group A and 27 patients in group B at just 6 and 12 months ***:The mean age in group A was 59.2±8.0 while in group B was 57.8±*** each group,we compared day and night continence in a period of 3 and 6 *** in group A,day continence after 3 months was 81.5% which improved to 96.3% after 6 months postoperatively with significant P-value(0.025).Night continence after 3 months was fair in 66.7%,unsatisfactory in 33.3% and 0% for good state which improved to 70% for fair state,18% unsatisfactory and 11% for good state after 6 months with significant P-value(0.035)while in group B,day continence after 3 months and 6 months postoperatively was 100% and night continence after 3 months was good in 0.0%,fair in 78.6% and unsatisfactory in 21.4% which improved to 10.7% for good state,85.7% for fair state and 3.6% for unsatisfactory after 6 months with significant P-value(0.005).Conclusion:There are no significant differences between detubularized ileocaecal and ileal neobladder in relation to contin

关键词： Bladder cancer radical cystectomy ileocaecal ileal neobladder urodynamic