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Diode Pumped High Peak Power Quasi Q-Switched and Passively Q-Switched Nd:YVO<sub>4</sub>Lasers at 1064 nm and 532 nm using Cr:YAG and KTP crystals

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Optics and Photonics Journal 2013年第1期3卷 51-62页

作者： Ashraf F. el-sherif mahmoud m. Talat military Technical Institute Cairo Egypt Townes Laser Institute CREOL College of Optics and Photonics University of Central Florida Orlando USA

Diode end-pumped solid-state lasers have the potential to yield high quality laser beams with high efficiency for laser range finding and warning receiver applications as well as day and night military laser designation systems. In this paper we presents theoretical calculations using Advanced Dynamics Professional LASCAD software and experimental studies for a high power pigtailed fiber diode laser module of 8 W operating at 808 nm with a specially designed high efficiency cooling system, end pumped high-efficiency Nd:YVO4 laser of 3 × 3 × 10 mm rod and overall cavity length of 44 mm. To the best of our knowledge a self Q-switching effects was generated in Nd:YVO4 laser by changing the cavity dimensions and the position of the intracavity KTP crystal at certain regime of operation for the first time, in which the cavity length is reduced to be 30 mm and the distance between Nd:YVO4 rod and KTP crystal is only 1mm. Self Q-switched laser pulse at 532 nm with high peak power of 96 W, pulse width of 88 ns at FWHm and repetition rate of 400 kHz was achieved. Experimental studies of a passive Q-switched Nd:YVO4 laser using Cr:YAG crystal with three different transmissions of 30%, 40% and 70% were investigated. Passive Q-switched laser pulse at 1064 nm and narrow line width of less than 1.5 nm with highest peak power of nearly 18 kW, short pulse width of less than 4 ns at FWHm and higher repetition rate of 45 kHz using Cr:YAG with transmission of 30% was achieved for the first time.

关键词： High Power Diode Laser High Power Nd:YVO4 Laser Cr:YAG Saturable Absorber mirror Passive Q-Switching KTP Crystal Self Q-Switching Special Cooling System

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Genetics of congenital and infantile nephrotic syndrome

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World Journal of Pediatrics 2019年第2期15卷 198-203页

作者： Sara Nawfal Sharief Nada Abdullatif Hefni Walaa Ali Alzahrani Iman Ibrahim Nazer marwa Abdullah Bayazeed Khalid A.Alhasan Osama Y.Safdar sherif m.el-Desoky Jameela Abdulaziz Kari King Abdulaziz University JeddahKingdom of Saudi Arabia College of medicine Pediatric DepartmentKing Saud UniversityRiyadhKingdom of Saudi Arabia Department of Pediatrics Faculty of MedicinePediatric Nephrology Center of ExcellenceKing Abdulaziz UniversityPO Box 80215Jeddah 21589Kingdom of Saudi Arabia

Background Congenital and infantile nephrotic syndrome (CNS and INS) are rare inherited defects in glomerular filtration involving a variety of gene *** study aimed to analyze all genetic mutations associated with congenital and infantile nephrotic syndrome treated at our *** also discussed our different approach secondary to culture and *** A retrospective single-center study of all children diagnosed as NS before the age of l year over a duration of over one *** Twenty-nine children (12 boys) were included in the *** median age (range) was 2.4 (0.1-12) months (20 CNS and 9 INS).Consanguinity was present in 90% of *** genetic analysis' results were only available for 20 *** underlying causative homozygous mutation was detected in 18 children (90%):NPHS1 (9),NPHS2(2),LAmB2(3),PLCE1(1),WT1(1),and ITSN1 novel mutation (2).One child had heterozygous mutation of NPHS2 and another child had heterozygous mutation of NPHS1 which could not explain the *** CNS cases were all managed with intermittent intravenous albumin infusion,ACEi,diuretics,and *** of the children were managed by nephrectomy followed by peritoneal dialysis (PD) because of limited *** one child achieved partial remission,while 15 children died at a median (range) age of 5.8 (1.25-29) *** remaining 14 children were followed up for an average of 36 (3.9-120) *** children progressed to end-stage kidney disease and PD was performed in only two *** NPHS1 is the main underlying cause of CNS and INS in our study *** and INS were associated with high morbidity and mortality.

关键词： Congenital nephrotic Infantile nephrotic Genetics Outcome

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Outcome of percutaneous drainage for septic complications coexisted with COVID-19

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World Journal of Radiology 2022年第4期14卷 91-103页

作者： mohamed A Deif Ahmad m mounir sherif A Abo-Hedibah Ahmed m Abdel Khalek Ali H elmokadem Department of Radiology National Liver InstituteMenoufia UniversityShibin Al Kawm 32521Egypt Department of Radiology Mansoura UniversityMansoura 35516Egypt Department of Radiology Cairo universityCairo 12613Egypt

BACKGROUND The resulting tissue hypoxia and increased inflammation secondary to severe coronavirus disease 2019(COVID-19)combined with viral load,and other baseline risk factors contribute to an increased risk of severe sepsis or co-existed septic condition *** To describe the clinical,radiological,and laboratory characteristics of a small cohort of patients infected by severe acute respiratory syndrome coronavirus 2 who underwent percutaneous drainage for septic complications and their postprocedural *** This retrospective study consisted of 11 patients who were confirmed to have COVID-19 by RT-PCR test and required drain placement for septic *** mean age±SD of the patients was 48.5±14 years(range 30-72 years).Three patients underwent cholecystostomy for acute acalculous *** drainage was performed in seven patients;two peripancreatic collections;two infected leaks after hepatic resection;one recurrent hepatic abscess,one psoas abscess and one lumbar *** patient underwent a percutaneous nephrostomy for acute *** Technical success was achieved in 100%of patients,while clinical success was achieved in 4 out of 11 patients(36.3%).Six patients(54.5%)died despite proper percutaneous drainage and adequate antibiotic *** patient(9%)needed operative *** patients(18.2%)had two drainage procedures to drain multiple fluid *** patients(18.2%)had repeat drainage procedures due to recurrent fluid *** average volume of the drained fluid immediately after tube insertion was 85 ***-up scans show a reduction of the retained content and associated inflammatory changes after tube insertion in all *** was no significant statistical difference(P=0.6 and 0.4)between the mean of WBCs and neutrophils count before drainage and seven days after *** lymphocyte count shows significant increased seven days after drainage(P=0.03).CONCLUS

关键词： COVID-19 SARS-CoV-2 Coronavirus Sepsis Drainage Abscess

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Can We Predict menorrhagia with Intrauterine Contraceptive Device (IUCD) Insertion?

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Open Journal of Obstetrics and Gynecology 2017年第7期7卷 753-766页

作者： Ghada m. mansour sherif H. Hussein Haitham F. mohammed sherif F. el mekkawy sherif A. Akl Asmaa A. Abd el Dayem Department of Obstetrics and Gynecology Ain Shams University Cairo Egypt Ashmoun Hospital Ministry of Health Hospitals Cairo Egypt

Objective: Studying sub endometrial vascularity and blood flow in cases using intrauterine contraceptive devices for contraception with and without menorrhagia compared to cases not using intrauterine contraceptive devices. methods: Three hundred and fifteen women attending gynecology and family planning outpatient clinics in the maternity hospital, Ain Shams University were included in the study. They were classified into three groups, 105 women using IUCD with menorrhagia (group I), 105 women using IUCD without menorrhagia (group II), and 105 normal controls not using IUCD (group III). After excluding local causes for bleeding, blood disease or any medical disorders, transvaginal ultrasound including three dimensional power Doppler (3DPD) ultrasound was done for all women. Right and left uterine artery pulsatility index (PI) and resistance index (RI) were calculated, subednometrial blood flow RI and PI were obtained then 3DPD Vascular indices (VI, FI and VFI) of subendometrial blood flow were obtained for all cases. Statistical analysis was done to compare between the three groups. Results: A significant statistical difference was found as regards subendometrial vascularity indices, while there was no difference as regards bilateral uterine arteries Doppler indices in the three groups. Conclusion: Subendometrial vascularity in cases of menorrhagia with IUCD was markedly higher than in cases without menorrhagia and cases with no IUCD. 3DPD may be used for selection of cases prior to insertion of IUCD.

关键词： Intrauterine Contraceptive Devices IUCD 3D Power Doppler Ultrasound menorrhagia

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Nanothermite colloids: A new prospective for enhanced performance

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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

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独立变桨控制及其对风电机组设计、性能与运行的影响

独立变桨控制及其对风电机组设计、性能与运行的影响

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作者： sherif el-Henaoui 穆格公司

如何设计开发可以降低总体发电成本的风电机组?回答这个问题时,必须考虑投资成本和运行维护(O&m)成本。降低负荷对于提高风电机组效率和延长机组寿命具有重要作用,是本文的一项重点。在尝试降低风电机组构件的负荷时,设计商重点研究的...

如何设计开发可以降低总体发电成本的风电机组?回答这个问题时,必须考虑投资成本和运行维护(O&m)成本。降低负荷对于提高风电机组效率和延长机组寿命具有重要作用,是本文的一项重点。在尝试降低风电机组构件的负荷时,设计商重点研究的是变桨控制系统。本文介绍了这一领域的最新技术进展和研究成果,尤其是独立变桨控制(IPC)的相关方面。

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Novel aspects for thermal stability studies and shelf life assessment of modified double-base propellants

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Defence Technology（防务技术） 2019年第3期15卷 300-305页

作者： sherif elbasuney Ashraf.m. A. elghafour mostafa Radwan Ahmed Fahd Hosam mostafa Ramy Sadek Amr motaz School of Chemical Engineering Military Technical College Kobry El-Kobba Cairo Egypt British University in Egypt Elshrouk city Cairo Egypt

modified DB propellants, based on energetic nitramine(RDX) were manufactured by solventless extrusion process. Thermal stability and shelf life assessment of modified DB propellant were investigated. Shelf life assessment was evaluated using Van’t Hoff’s formula and artificial aging at 70℃ up to120 days. Quantification of total heat released and heat flow with aging time was conducted using differential scanning calorimetry(DSC) and thermal activity monitoring(TAmIII) respectively. modified DB formulation based on 20 wt % RDX demonstrated enhanced thermal stability in terms of controlled heat flow, and slow decomposition reactions at elevated temperature. This formulation demonstrated extended service life up to 56 years compared with reference formulation. These novel finding was ascribed to the high thermal stability of RDX and its compatibility with DB constituents. This manuscript shaded the light on novel and effective approach for thermal stability via monitoring thermal activity with aging.

关键词： Double-base propellant Thermal stability Artificial aging Shelf-life assessment

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Effect of laser assisted hatching on outcome of assisted reproductive technology

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Open Journal of Obstetrics and Gynecology 2013年第5期3卷 18-23页

作者： Amro elhussieny mohamed el mandouh sherif Hanafi Ghada m. mansour Ahmed el-Kotb Department of Obstetrics and Gynecology Ain Shams University Cairo Egypt

Objective: To determine whether laser-assisted hatching can improve clinical outcome of assisted reproductive techniques in both unselected patients and patients with advanced female age, with recurrent implantation failure, or who are using frozen-thawed embryos. Study design: Prospective randomized study. Patients and methods: 179 consecutive women scheduled for intracytoplasmic sperm injection (ICSI) were randomised to either laser assisted hatching (LAH) or non LAH group. Patients were divided into 94 test and 85 control groups. On the day of embryo transfer, the zona pellucida of the selected embryos in the test group was thinned by using an infrared optical laser system, whereas in the control group they were left intact. Clinical pregnancy rates (CPR) and implantation rates (IR) were estimated. Result(s): Patients that underwent LAH (n = 94) had CPR, and IR of 35.1% and 50%, respectively. Patients that did not undergo LAH (n = 85) had lower CPR (28.2%, P = 0.324) and IR (33%, P = 230), with no statistically significant difference P Conclusion: The current study suggested that there is no need for the routine use of laser assisted hatching. However, there is evidence of laser assisted hatching benefit in selected

关键词： Laser-Assisted Hatching Advanced Female Age Implantation Failures Embryo Cryopreservation and Pregnancy Rate

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Novel approach to quantify the chemical stability and shelf life of modified double-base propellants

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Defence Technology（防务技术） 2018年第6期14卷 720-724页

作者： Ashraf m.A.elghafour mostafa Radwan Ahmed Fahd Hosam E.mostafa sherif elbasuney School of Chemical Engineering Military Technical CollegeKobry El-KobbaCairoEgypt British University in Egypt Elshrouk CityCairoEgypt

Double-base(DB) propellant is vulnerable to auto-catalytic decomposition reactions during storing with the evolution of nitrogen oxides. modified DB propellant based on energetic nitramines(RDX) can offer enhanced thrust and action time. This study is devoted to evaluate the impact of RDX on chemical stability and shelf life of DB propellant. Extruded modified DB propellant based on RDX was manufactured by solventless extrusion process. Shelf life assessment was performed using an artificial aging at70 ℃ up to 120 days and employing Van't Hoffs formula. Quantification of evolved NOx gases and stabilizer depletion with aging time was conducted using Bergmann-Junk test and HPLC *** DB formulation based on RDX 20 wt % demonstrated enhanced chemical stability and extended service life up to 46 years compared with reference formulation. This finding was ascribed to the high chemical and thermal stability of RDX as well as its compatibility with DB constituents; no side chemical reactions could take place during storing. This manuscript shaded the light on RDX as effective energetic constituent that offered DB propellants with enhanced performance, good chemical stability, and extended service life.

关键词： Double-base propellant Chemical stability Artificial aging Shelf life assessment

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Impact of transjugular intrahepatic porto-systemic shunt on post liver transplantation outcomes: Study based on the United Network for Organ Sharing database

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World Journal of Hepatology 2017年第2期9卷 99-105页

作者： Khalid mumtaz sherif metwally Rohan m modi Nishi Patel Dmitry Tumin Anthony J michaels James Hanje Ashraf el-Hinnawi Don Hayes Jr Sylvester m Black Wexner medical Center Gastroenterology Hepatology and Nutrition Division the Ohio State University Department of Internal medicine the Ohio State University Department of Pediatrics the Ohio State University Department of Surgery the Ohio State University Section of Pulmonary medicine the Ohio State University

AIm To determine the impact of transjugular intrahepatic porto-systemic shunt(TIPS) on post liver transplantation(LT) *** Utilizing the United Network for Organ Sharing(UNOS) database, we compared patients who underwent LT from 2002 to 2013 who had underwent TIPS to those without TIPS for the management of ascites while on the LT waitlist. The impact of TIPS on 30-d mortality, length of stay(LOS), and need for re-LT were studied. For evaluation of mean differences between baseline characteristics for patients with and without TIPS, we used unpaired t-tests for continuous measures and χ~2 tests for categorical measures. We estimated the impact of TIPS on each of the outcome measures. multivariate analyses were conducted on the study population to explore the effect of TIPS on 30-d mortality post-LT, need for re-LT and LOS. All covariates were included in logistic regression *** We included adult patients(age ≥ 18 years) who underwent LT from may 2002 to September 2013. Only those undergoing TIPS after listing and before liver transplant were included in the TIPS group. We excluded patients with variceal bleeding within two weeks of listing for LT and those listed for acute liver failure or hepatocellular carcinoma. Of 114770 LT in the UNOS database, 32783(28.5%) met inclusion criteria. Of these 1366(4.2%) had TIPS between the time of listing and LT. We found that TIPS increased the days on waitlist(408 ± 553 d) as compared to those without TIPS(183 ± 330 d), P multivariate analysis showed that TIPS had no effect on 30-d post LT mortality(OR = 1.26; 95%CI: 0.91-1.76) and re-LT(OR = 0.61; 95%CI: 0.36-1.05). Pre-transplant hepatic encephalopathy added 3.46 d(95%CI: 2.37-4.55, P me on waitlist for LT. more importantly, TIPS was not associated with 30-d mortality and re-LT, but it did lengthen hospital LOS after transplantation.

关键词： Transjugular intrahepatic porto 全身的分流分流肝移植腹水为结束阶段肝疾病当模特儿死亡 Transjugular

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