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Spectrally adapted red flare tracers with superior spectral performance

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Defence Technology（防务技术） 2017年第6期13卷 406-412页

作者： Ramy Sadek mohamed kassem mohamed Abdo Sherif elbasuney School of Chemical Engineering Military Technical CollegeKobry ElkobaCairoEgypt

The production of bright light, with vivid color, is the primary purpose of signaling, illuminating devices,and fire control purposes. This study, reports on the development of red flame compositions with enhanced performance in terms of luminous intensity, and color quality. The light intensity and the imprint spectra of developed red flame compositions to standard NATO red tracer(R-284 NATO) were measured using digital luxmeter, and UV-Vis. spectrometer. The main giving of this study is that the light intensity of standard NATO red tracer was increased by 72%, the color quality was also improved by60%(over the red band from 650 to 780 nm). This enhanced spectral performance was achieved by means of deriving the combustion process to maximize the formation of red color emitting species in the combustion flame. Thanks to the optimum ratio of color source to color intensifier using aluminum metal fuel; this approach offered the highest intensity and color quality. Upon combustion, aluminum was found to maximize the formation SrCL(the main reactive red color emitting species) and to minimize the interfering incandescent emission resulted from MgO and SrO. Quantification of active red color emitting species in the combustion flame was conducted using chemical equilibrium thermodynamic code named ICT. The improvement in red flare performance, established the rule that the color intensifier should be in the range from 10 to 15 Wt % of the total composition.

关键词： Pyrotechnics Colored flames Tracers Luminous intensity Molecular spectroscopy

Novel yellow colored flame compositions with superior spectral performance

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Defence Technology（防务技术） 2017年第1期13卷 33-39页

作者： Ramy Sadek mohamed kassem mohamed Abdo Sherif elbasuney School of Chemical Engineering Military Technical CollegeKobry El-KobbaCairoEgypt

The production of colored flames is the primary purpose of military signaling, projectile tracing, and illuminating devices. Certain elements and compounds when heated to high temperature have the unique property of emitting lines or narrow bands in the visible region(380-780 nm). This study, reports on the development of novel yellow colored flame compositions with enhanced spectral performance in terms of luminous intensity, and color quality to standard Russian yellow tracer. The light intensity and the imprint spectra of developed yellow flares were measured using digital luxmeter and UV e Vis. spectrometer respectively. The main giving of this study is that the light intensity, and color quality of Russian yellow tracer were improved by 287%, and 170% respectively. This was accomplished by means of optimizing the ratio of novel binder to color source using aluminum metal fuel. Aluminumbased formulations were found to maximize the formation of yellow reactive emitting specimens, and to eliminate any interfering incandescent emission resulted from Mg O. Quantification of yellow color emitting specimens in the combustion gaseous products was achieved using chemical equilibrium thermodynamic code named ICT(Institute of Chemical Technology in Germany, Virgin 2008); in an attempt to judge the light quality. This improvement in yellow flare performance established the rule that the emission intensity increases as the reaction temperature increases. In the meantime upper limit of temperature was avoided to maximize the color quality.

关键词： Pyrotechnics Colored flames Yellow tracer Atomic spectroscopy Color quality

Novel colored flames via chromaticity of essential colors

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Defence Technology（防务技术） 2019年第2期15卷 210-215页

作者： Ramy Sadek mohamed kassem mohamed Abdo Ahmed Fahd Hesham Tantawy Amir elsaidy Sherif elbasuney School of Chemical Engineering Military Technical College

Colored flame compositions have distinctive variety of applications ranging from military signaling,rocket tracking, and illuminating devices. Certain elements and compounds when heated to high temperature are able to emit unique wavelengths in the visible region. This study, reports on the development of novel colored flames that cannot be generated by emitting atomic/molecular species. This was achieved by using chromaticity of basic colored flames. Mixing of high quality primary colored flames including Blue, Yellow, and Red in proper ratio was conducted; any interfering incandescent emission resulted from MgO was eliminated using Al metal fuel. The spectral characteristics in terms of luminous intensity, and color quality were evaluated using digital luxmeter and UV-Vis. spectrometer *** quality mixed colored flames include violet, sweet pink, and marigold were developed. This study shaded the light on the state of the art for the real development of novel colored flame compositions and chromaticity of basic colored flames.

关键词： Pyrotechnics Colored flame Atomic spectroscopy Molecular spectroscopy Luminous intensity Color quality Chromaticity

Isolation and characterisation of human gingival margin-derived STRO-1/MACS^+ and MACS^-cell populations

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International Journal of Oral Science 2015年第2期7卷 80-88页

作者： Karim M Fawzy el-Sayed Sebastian Paris Christian Graetz Neemat kassem mohamed Mekhemar Hendrick Ungefroren Fred Fndrich Christof Drfer Clinic for Conservative Dentistry and Periodontology School of Dental MedicineChristian Albrechts University Oral Medicine and Periodontology Department Faculty of Oral and Dental MedicineCairo University Department of Operative and Preventive Dentistry Charite-Universitatsmedizin Berlin Department of Clinical Pathology Faculty of MedicineCairo University Clinic for Applied Cellular Therapy Christian Albrechts University

Recently,gingival margin-derived stem/progenitor cells isolated via STRO-1/magnetic activated cell sorting（MACS） showed remarkable periodontal regenerative potential in *** a second-stage investigation,the present study＇s aim was to perform in vitro characterisation and comparison of the stem/progenitor cell characteristics of sorted STRO-1-positive（MACS~＋） and STRO-1-negative（MACS^-） cell populations from the human free gingival *** were isolated from the free gingiva using a minimally invasive technique and were magnetically sorted using anti-STRO-1 ***,the MACS~＋ and MACS^- cell fractions were characterized by flow cytometry for expression of CD14,CD34,CD45,CD73,CD90,CD105,CD146/MUC18 and ***-forming unit（CFU） and multilineage differentiation potential were assayed for both cell *** marker expression was examined using real-time polymerase chain reaction（PCR）.MACS~＋ and MACS- cell fractions showed plastic ***~＋ cells,in contrast to MACS- cells,showed all of the predefined mesenchymal stem/progenitor cell characteristics and a significantly higher number of CFUs（P〈0.01）.More than 95%of MACS~＋ cells expressed CD105,CD90 and CD73;lacked the haematopoietic markers CD45,CD34 and CD14,and expressed STRO-1 and CD146/***- cells showed a different surface marker expression profile,with almost no expression of CD14 or STRO-1,and more than 95%of these cells expressed CD73,CD90 and CD146/MUC18,as well as the haematopoietic markers CD34 and CD45 and ***~＋ cells could be differentiated along osteoblastic,adipocytic and chondroblastic *** contrast,MACS- cells demonstrated slight osteogenic *** MACS~＋ cells showed significantly higher expression of collagen I（P〈0.05） and collagen III（P〈0.01）,whereas MACS^- cells demonstrated higher expression of osteonectin（P〈0.05;MannWhitney）.The present study is the first to compare gingival MACS~＋ and MACS- cell populations demo

关键词： gingival progenitor populations margin periodontal cytometry collagen isolation dental sorting

Multiobjective Nonlinear Symmetric Duality Involving Generalized Pseudoconvexity

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Applied Mathematics 2011年第10期2卷 1236-1242页

作者： mohamed Abd el-Hady kassem 不详

The purpose of this paper is to introduce second order (K, F)-pseudoconvex and second order strongly (K, F)- pseudoconvex functions which are a generalization of cone-pseudoconvex and strongly cone-pseudoconvex functions. A pair of second order symmetric dual multiobjective nonlinear programs is formulated by using the considered functions. Furthermore, the weak, strong and converse duality theorems for this pair are established. Finally, a self duality theorem is given.

关键词： Multiobjective Programming Second-Order Symmetric Dual Models Duality Theorems Pseudoconvex Functions Cones

A Modified Interactive Stability Algorithm for Solving Multi-Objective NLP Problems with Fuzzy Parameters in Its Objective Functions

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American Journal of Operations Research 2016年第1期6卷 8-16页

作者： mohamed Abd el-Hady kassem Ahmad M. K. Tarabia Noha mohamed el-Badry Mathematics Department Faculty of Science Tanta University Tanta Egypt Mathematics Department Faculty of Science Damietta University Damietta Egypt

This paper presents a modified method to solve multi-objective nonlinear programming problems with fuzzy parameters in its objective functions and these fuzzy parameters are characterized by fuzzy numbers. The modified method is based on normalized trade-off weights. The obtained stability set corresponding to α-Pareto optimal solution, using our method, is investigated. Moreover, an algorithm for obtaining any subset of the parametric space which has the same corresponding α-Pareto optimal solution is presented. Finally, a numerical example to illustrate our method is also given.

关键词： Multi-Objective Nonlinear Programming Stability Trade-Off Method Fuzzy Parameters

Effect of reperfusion strategy on QT dispersion in patients with acute myocardial infarction:Impact on in-hospital arrhythmia

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World Journal of Cardiology 2023年第3期15卷 106-115页

作者： mohamed aboel-kassem F Abdelmegid mohamed M Bakr Hamdy Shams-Eddin Amr A Youssef Ahmed Abdel-Galeel Department of Cardiovascular Medicine Assiut University Heart HospitalAssiut UniversityAssiut 71526Egypt Department of Cardiology Sohag Heart and GIT CenterSohag 85264Egypt Department of Cardiology Assiut Police HospitalAssiut 71526Egypt Department of Cardiology Qena General HospitalQena 92354Egypt

BACKGROUND Myocardial ischemia and ST-elevation myocardial infarction(STEMI)increase QT dispersion(QTD)and corrected QT dispersion(QTcD),and are also associated with ventricular *** To evaluate the effects of reperfusion strategy[primary percutaneous coronary intervention(PPCI)or fibrinolytic therapy]on QTD and QTcD in STEMI patients and assess the impact of the chosen strategy on the occurrence of in-hospital *** This prospective,observational,multicenter study included 240 patients admitted with STEMI who were treated with either PPCI(group I)or fibrinolytic therapy(group II).QTD and QTcD were measured on admission and 24 hr after reperfusion,and patients were observed to detect in-hospital *** There were significant reductions in QTD and QTcD from admission to 24 hr in both group I and group II *** and QTcD were found to be shorter in group I patients at 24 hr than those in group II(53±19 msec vs 60±18 msec,P=0.005 and 60±21 msec vs 69+22 msec,P=0.003,respectively).The occurrence of in-hospital arrhythmia was significantly more frequent in group II than in group I(25 patients,20.8%vs 8 patients,6.7%,P=0.001).Furthermore,QTD and QTcD were higher in patients with in-hospital arrhythmia than those without(P=0.001 and P=0.02,respectively).CONCLUSION In STEMI patients,PPCI and fibrinolytic therapy effectively reduced QTD and QTcD,with a higher observed reduction using *** was associated with a lower incidence of in-hospital arrhythmia than fibrinolytic *** addition,QTD and QTcD were shorter in patients not experiencing in-hospital arrhythmia than those with arrhythmia.

关键词： Arrhythmia QT dispersion ST-segment elevation myocardial infarction Reperfusion Primary percutaneous coronary intervention Fibrinolytic therapy

Pull Breech out versus Push Impacted Head up in Emergency Cesarean Section: A Comparative Study

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Open Journal of Obstetrics and Gynecology 2014年第6期4卷 260-265页

作者： Hend S. Saleh Gamal A. kassem mohamed el Said mohamed Moustafa A. Ibrahiem Manal M. el Behery Faculty of Medicine Zagazig University Zagazig Egypt

Objective: To compare maternal and fetal outcome associated with two methods Reverse breech extraction versus Head pushing to deliver the impacted fetal head in advanced labor requiring emergency Cesarean section. Method: A prospective comparative study was conducted on 80 pregnant women at term with cephalic presentation in advanced labour, requiring emergency Cesarean Section. Reverse breech extraction technique (pull method) was used in 40 cases (group I) and pushing the head up through the vagina (“push” method) was tried in (group II) 40 cases. The maternal outcome was assessed by extension of the uterine Incision, bladder injury, intra and postoperative blood transfusion, Postpartum hemorrhage, wound infection and duration of hospital stay. Fetal outcome was Apgar score and admission to neonatal intensive care unit. Results: Extension of the uterine incision was significantly lower in women undergoing reverse breech extraction compared to cephalic delivery (20% versus 50%;p = 0.001). The mean operative time (pull group) was lower than that in the (push group) 59.7 ± 4.2, versus 75.2 ± 6.1 p = 0.001 and blood loss was significantly lower in the (pull group) than that in the (push group) 878 ± 67 ml, versus 1321 ± 57 ml, p = 0.001. No significant difference between groups regarding maternal and neonatal outcome. Conclusion: Reverse breech extraction (pull) is safer than pushing head up through vagina (push) for delivery of a deeply impacted fetal head in advanced labour sensitizing emergency Cesarean Section and is associated with the least maternal complications.

关键词： Deeply Engaged Head Obstructed Labor Cesarean Section Reverse Breech Extraction Head Push Method

Impact of renal transplantation on cardiac morphological and functional characteristics in children and adults

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World Journal of Nephrology 2016年第6期5卷 517-523页

作者： Sahier Omar el-Khashab Eman el-Sayed mohamed Mahmoud A Soliman Hussein Heshmat kassem Amin Roshdy Soliman Department of Nephrology Kasr Al-Ainy Cairo University Department of Medicine Kasr Al-Ainy Cairo University Department of Cardiology Kasr AlAiny Cairo University

AIM To compare the effects of renal transplantation on cardiac functions in children and *** One hundred and ten patients attending the nephrology outpatient clinic were enrolled in this study and were divided into six groups. The first two groups consisted each of 30 renal transplant patients who had a successful renal transplantation more than six months, but less than one year. Group Ⅰ were less than 18 years and group Ⅱ were more than 18 years. The third and fourth groups, each were 20 chronic renal failure patients on regular hemodialysis. Again, group Ⅲ were less than 18 years and group Ⅳ were more than 18 years. Group Ⅴ and Ⅵ(The control Groups) consisted each of 5 subjects below and above 18 years of age, respectively with normal kidney functions. All patients were subjected to history and examination. The kidney functions and the hemoglobin were analyzed. Afterobtaining informed consent, echocardiography was done to all *** There was a statistically significant improvement(P < 0.0001) in all cardiac parameters. A regression in left ventricular end diastolic volume(LVED) both in children(4.7 ± 0.8 to 4.2 ± 0.5) and in adults(5.9 ± 0.7 to 4.9 ± 0.6) were found. There was a regression in left ventricular end systolic volume(LVES) both in children(3.1 ± 0.6 to 2.4 ± 0.4) and in adults(4.1 ± 0.9 to 3.1 ± 0.5). Fractional shortening improves both in children(32.6 ± 5.3 to 41.7 ± 7.6) and in adults(29.0 ± 6.6 to 36.5 ± 4.1). The improvement in ejection fraction(EF) was higher in children(59.7 ± 7.0 to 71.9 ± 6.1) than in adults(52.0 ± 12.5 to 64.8 ± 5.9). However, this degree of improvement(in children: 12.2 ± 5.1) did not show statistical difference(P-value 0.8), when compared to adults(12.7 ± 9.8). CONCLUSION After renal transplantation cardiac functions and morphology(EF/LVED/LVES) do improve markedly and rapidly in both children and adults.

关键词： Echocardiography chronic renal disease Renal transplantation Cardiac problems