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Optical and near-infrared photometric study of NGC 6724

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Research in Astronomy and Astrophysics 2018年第2期18卷 37-42页

作者： Reda Bendary Ashraf Tadross Priya Hasan Anas Osman ahmed essam National Research Institute of Astronomy & Geophysics 11421-Helwan Cairo Egypt Maulana Azad National Urdu University Gachibowli Hyderabad - 500 032 India

BVRI CCD photometry of the poorly studied open cluster NGC 6724 has been carried out down to a limiting magnitude of V-20 mag. The stars of the cluster have been observed using the Newtonian focus （f/4.84） of the 74-inch telescope at Kottamia Astronomical Observatory in Egypt. Also, the 2MASS - JHK system is used to confirm the results we obtained. The main photometric parameters have been estimated for the present object; the diameter is found to be 6 arcmin, the distance is 15304-60pc from the Sun and the age is 900＋50Myr. The optical reddening E（B - V） = 0.65 mag, while the infrared reddening is E（J - H） = 0.20 mag. The slope of the mass function distribution and the relaxation time estimations indicate that cluster NGC 6724 is dynamically relaxed.

关键词： Milky Way -- open clusters and associations: individual (NGC 6724) - optical photom-etry - IR photometry - color-magnitude diagrams

Effect of heat input and filler metals on weld strength of gas tungsten arc welding of AISI 316 weldments

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China Welding 2020年第1期29卷 8-16页

作者： essam ahmed Ramy ahmed A EL-Nikhaily A R S Essa Metallurgical and Materials Engineering Department Faculty of Petroleum and Mining EngineeringSuez University43721 Egypt Mechanical Department Faculty of Industrial EducationSuez University43721 Egypt Mechanical Engineering Department Egyptian Academy for Engineering&Advanced TechnologyAffiliated to Ministry of Military ProductionCairo 3056Egypt

The present work investigates the effect of filler metals and heat input on weld bead geometry and mechanical properties of alloy316 welded by using ***309 L,ER316 L and ERNi Cr Mo-3 filler metals,are applied to study their effect on the *** defects are examined using radiographic *** mechanical properties of welds are evaluated through uniaxial testing,hardness measuring,and bending *** mechanical properties and cooling rate decrease with increasing heat *** strength,yield stress and percentage elongation of weldments using three fillers are *** results are obtained using ERNi Cr ***,weld nugget area,cooling time and solidification time increases with increasing heat ***,applying bending test on weld samples,cracks,tearing and surface defects are not observed.

关键词： TIG welding filler metals nugget area stainless steel cooling rate

联合国苏丹综合过渡期援助团对稳定苏丹局势的作用

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联合国苏丹综合过渡期援助团对稳定苏丹局势的作用

作者： ahmed essam ahmed Mohamed 吉林大学

学位级别：硕士

联合国特别政治任务特派团在其所扮演的角色和主要职责上还没有一个清晰明确、被广泛认可的概念,但其已经成为一种趋势。这些特派团被授权在战后恢复国家或正在经历冲突的国家成立,所有这些特派团根据委托国的需要对其进行不同领域的援... 详细信息

联合国特别政治任务特派团在其所扮演的角色和主要职责上还没有一个清晰明确、被广泛认可的概念,但其已经成为一种趋势。这些特派团被授权在战后恢复国家或正在经历冲突的国家成立,所有这些特派团根据委托国的需要对其进行不同领域的援助,但是它们通常都有一个共同的议题,即关于对平民的保护。大多数政治特派团主要在政治稳定、经济动员等领域协助面临冲突威胁的国家,监督国内侵犯人权行为的情况,促进各利益相关方的协商和调节的进程。2019年,在苏丹军方推翻奥马尔·巴希尔政权并建立过渡军事委员会后,“自由与变革力量”、“抵抗委员会”等的抗议领导组织企图与军事委员会共享权利,双方之间进行了超过一年的协商,最终就政治和宪法文件达成协议。这种特殊的权力共享关系与国内情况促使苏丹过渡政府致函联合国安理会,期望联合国成立国际苏丹援助团。基于此,联合国安理会于2020年6月3日通过第2524号决议,为苏丹设立一个特别政治特派团——联合国苏丹综合过渡期援助团(UNITAMS)向苏丹过渡政府提供必要的援助以使其度过过渡期,同时秘书长任命一名驻苏丹特别代表前往特派团,并要求他每90天向联合国安理会提交一份报告以说明苏丹目前的局势以及UNITAMS在援助进程中的作用。革命过后,过渡政府力求实现苏丹人民同世界人民一道对民主治理的殷切盼望。他们相信联合国这一国际性组织能够为其过渡政府提供一切需要的帮助,正像UNITAMS从第一天起向苏丹人民承诺的那样。并且UNITAMS承诺会在苏丹临时政府的授权下开展工作,与苏丹过渡政府以及区域和全球合作伙伴合作完成政府选举,然后将权力移交给民选政府。为了评估特派团在维持苏丹稳定方面的作用,本论文将回答该研究问题:UNITAMS在维持苏丹稳定中起到何种作用?研究结果表明,在军事政变到签署宪法文件的政治危机过程中,UNITAMS在政治问题上的主导作用突显,在政治稳定问题上发挥了相当大的作用。在此期间,UNITAMS领导过渡军事委员会与自由与变革力量间的谈判进程,并使得双方在2021年11月21日签署一项政治协议以解决不稳定局势。尽管苏丹政治形势更加复杂,特别是在苏丹总理阿卜杜拉·哈姆杜克辞职以及反对军事政变的示威运动兴起后,UNITAMS与非洲联盟和伊加特合作,领导协商进程的进行,以召集苏丹利益攸关方达成协议,继续领导该国走向民主统治。经济上,通过与国际社会建立良好关系以及借助对苏丹友好国家的支持,苏丹开始在债务减免、重返国际金融体系和接受外部投资方面取得重大进展。达尔富尔混合行动的撤军对UNITAMS来说是一个困难的挑战,因为它必须保护平民并监管当局对各种形式的侵犯行为的应对。本文基于定性分析的方法收集相关资料,以分析UNITAMS每90天向联合国安理会提供的报告,该报告及时向联合国安理会汇报了当时苏丹的现实情况以及UNITAMS在维护苏丹政治稳定等任务方面发挥的作用,并基于访谈法访谈掌握该特派任务信息的相关人员以及通过搜索法搜索有关该特派团联合国秘书长特别代表的相关发表。资料收集的过程中遇到的最大的挑战是,掌握资料的人数稀少,即使是苏丹当日群众以及活跃在政治和社会领域中的人士。因此,该研究在激发人们去研究和了解联合国政治特派团尤其是对冲突中的国家或和平恢复中的国家提供援助的援助团具有重大意义。本研究共分为四章,第一章是引言,首先阐述作为一个关注人的国际组织的联合国的出现以及它帮助维护世界和平与安全的部门与人道主义援助的概念,其次阐述了本研究的重要性以及研究方法及资料来源;第二章讨论联合国苏丹综合过渡期援助团的设立及其与苏丹过渡政府协调运作的重要伙伴关系;第三章描述了联合国苏丹综合援助团在各领域对苏丹过渡的帮助与作用;第四章讨论了受访者对联合国苏丹综合援助团在维护苏丹稳定方面的作用的看法,以及其存在在当前局势中的重要性,尤其是该援助团对2021年10月25日军事政变苏丹总体局势发生改变后苏丹局势的作用。

关键词：苏丹 R2P SPMs UNITAMS 联合国宪章第六章咨询

Association of the Monocyte to HDL Cholesterol Ratio with Thrombus Burden in Patients with Acute Coronary Syndrome

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World Journal of Cardiovascular Diseases 2019年第10期9卷 746-758页

作者： Ghada Mahmoud Soltan Neveen I. Samy Wassam ElDin Hadad ELShafey Safwat essam ahmed Department of Cardiology Menoufia University Hospitals Menoufia Egypt Department of Cardiology National Heart Institute Cairo Egypt

Background: Intracoronary thrombus burden is associated with some adverse events and poor prognosis in patients with Acute Coronary Syndrome. Identifying predictors of the intracoronary thrombus burden may contribute to the management of Acute Coronary Syndrome. Objective: To assess the correlation between the Monocyte to HDL Cholesterol ratio with thrombus burden in patients with Acute Coronary Syndrome. Patients and Methods: 138 patients with ACS who were admitted to CCU department in National Heart Institute Cairoand Menoufia University Hospitals, Menoufia, underwent primary percutaneous coronary intervention (PCI).Angiographic thrombus burden was classified based on thrombolysis in myocardial infarction (TIMI) thrombus grades. The patients were grouped into 2 categories of low thrombus burden (grades 0 - 3) (49.7%) and high thrombus burden (grades 4 and 5) (50.3%). Results: On analysis we found that the MHR was significantly higher in the high thrombus burden group compared with the low thrombus (0.052 ± 0.019 vs 0.014 ± 0.008);P 0.001. Conclusion: Among Acute Coronary Syndrome patients underwent Primary PCI, MHR was independent predictor of high thrombus burden in patients with Acute Coronary Syndrome.

关键词： Monocyte to HDL Ratio Acute Coronary Syndrome Thrombus Burden

The Role of Electrocardiogram DETERMINE Score in Prediction of Coronary Artery Disease Severity

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World Journal of Cardiovascular Diseases 2024年第9期14卷 567-580页

作者： Ismail N. El-Sokkary essam ahmed Khalil Mohammed Wael Badawi Ibrahim K. Gamil Shousha Abdalla A. Elsebaey Mohamed Kamal Rehan Mahmoud Ibrahim Elshamy Yasser ahmed Sadek Department of Cardiovascular & Thoracic Surgery Faculty of Medicine Al-Azhar University Cairo Egypt Department of Cardiology Al-Azhar University Cairo Egypt Department of Internal Medicine Beni-Sueif University Beni Suef Egypt Department of Radiology Al-Azhar University Cairo Egypt Department of Cardiology Helwan University Cairo Egypt

Background: A major cause of mortality and disability on a global scale is myocardial infarction (MI). These days, the most reliable way to detect and measure MI is via cardiovascular magnetic resonance imaging (CMR). Aims and Objectives: To evaluate the effectiveness of the Electrocardiogram DETERMINE Score in predicting the severity of coronary artery disease (CAD) in patients who have experienced an Acute Myocardial Infarction (AMI) & to assess improvements in left ventricular function at 6 months following coronary artery bypass grafting (CABG). Subjects and Methods: This Observational cohort study was done at the Cardiology and Radiology department and cardiac surgery department, Al-Azhar university hospitals and Helwan University hospital. The study involved 700 cases who patients diagnosed with Acute Myocardial Infarction and fulfilled specific criteria for selection. Result: There was highly statistically significant relation between Myocardial infarction size and ECG Marker Score as mean infarct size elevated When the number of ECG markers increased. There was a highly statistically significant relation between myocardial infarct segments, myocardial infarction size and improvement of cardiac function 6 months post-CABG. Conclusion: The study found that larger myocardial infarctions corresponded with higher DETERMINE Scores. It concluded that an ECG-based score better estimates infarct size than LVEF alone. Additionally, there was a significant statistical correlation between the size and segmentation of myocardial infarction and better cardiac function six months after CABG.

关键词： Electrocardiogram DETERMINE Score Coronary Artery Disease Outcome Acute Myocardial Infarction Coronary Artery Bypass Grafting

Synthesis of thiopyrano[4″,3″:4′,5′]pyrido[3′,2′:4,5]furo[3,2-d]pyrimidines

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Chinese Chemical Letters 2010年第6期21卷 669-673页

作者： essam Kh. ahmed Mohamed A. Ameen Chemistry Department Faculty of ScienceEl Minia UniversityEl Minia 61519Egypt

Reactions of the 6-hydroxy-thiopyrano[3,4-c]pyridine-5-carbonitrile derivative 1 withα-halo-carbonyl compounds gave the ortho-substituted intermediates 2a-c which were converted into furo[2,3-b]thiopyrano[4,3-d]pyridines 3a-c by fusion of a furan moiety under basic *** cyclization of 3a-c led to a fusion of a pyrimidine ring,yielding the tetracyclic products 6,7 and *** addition,condensation of 6 with various aromatic aldehydes afforded the corresponding imines 9a,*** reaction of 7 gave products 10a,b.

关键词： S N-Heterocycles S N O-Heterocyles Furo[2 3-b]thiopyrano[4 3-d]pyridine Thiopyranopyridofuropyrimidines

Model inference using the Akaike information criterion for turbulent flow of non-Newtonian crude oils in pipelines

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Petroleum Science 2015年第3期12卷 492-500页

作者： ahmed H.Kamel Ali S.Shaqlaih essam A.Ibrahim College of Business & Engineering University of Texas of the Permian Basin Department of Mathematics & Information Sciences University of North Texas at Dallas

The friction factor is a crucial parameter in calculating frictional pressure losses. However, it is a decisive challenge to estimate, especially for turbulent flow of non-Newtonian fluids in pipes. The objective of this paper is to examine the validity of friction factor correla- tions adopting a new informative-based approach, the Akaike information criterion （AIC） along with the coeffi- cient of determination （R2）. Over a wide range of measured data, the results show that each model is accurate when it is examined against a specific dataset while the E1-Emam et al. （Oil Gas J 101：74-83, 2003） model proves its supe- riority. In addition to its simple and explicit form, it covers a wide range of flow behavior indices and generalized Reynolds numbers. It is also shown that the traditional belief that a high R2 means a better model may be mis- leading. AIC overcomes the shortcomings of R2 as a trade between the complexity of the model and its accuracy not only to find a best approximating model but also to develop statistical inference based on the data. The authors present AIC to initiate an innovative strategy to help alleviate several challenges faced by the professionals in the oil and gas industry. Finally, a detailed discussion and models＇ ranking according to AIC and R2 is presented showing the numerous advantages of *** Friction factor - Pipeline Information theory Non-Newtonian Turbulent

关键词： Friction factor - Pipeline Informationtheory Non-Newtonian Turbulent

Insulin resistance in diabetes: The promise of using induced pluripotent stem cell technology

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World Journal of Stem Cells 2021年第3期13卷 221-235页

作者： ahmed K Elsayed Selvaraj Vimalraj Manjula Nandakumar essam M Abdelalim Diabetes Research Center Qatar Biomedical Research InstituteHamad Bin Khalifa UniversityQatar FoundationDoha 34110Qatar Centre for Biotechnology Anna UniversityChennai 600025India College of Health and Life Sciences Hamad Bin Khalifa UniversityQatar FoundationDoha 34110Qatar

Insulin resistance(IR)is associated with several metabolic disorders,including type 2 diabetes(T2D).The development of IR in insulin target tissues involves genetic and acquired *** at genetic risk for T2D tend to develop IR several years before glucose *** rodent models for both IR and T2D are being used to study the disease pathogenesis;however,these models cannot recapitulate all the aspects of this complex disorder as seen in each *** pluripotent stem cells(hPSCs)can overcome the hurdles faced with the classical mouse models for studying *** induced pluripotent stem cells(hiPSCs)can be generated from the somatic cells of the patients without the need to destroy a human ***,patient-specific hiPSCs can generate cells genetically identical to IR individuals,which can help in distinguishing between genetic and acquired defects in insulin *** the technologies of genome editing and hiPSCs may provide important information about the genetic factors underlying the development of different forms of *** studies are required to fill the gaps in understanding the pathogenesis of IR and *** this review,we summarize the factors involved in the development of IR in the insulin-target tissues leading to ***,we highlight the use of hPSCs to understand the mechanisms underlying the development of IR.

关键词： Type 2 diabetes Insulin target tissues Human pluripotent stem cells Induced pluripotent stem cells Genetic factors Disease modeling

Improvement of visual acuity based on optical coherence tomography patterns following intravitreal bevacizumab treatment in patients with diabetic macular edema

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International Journal of Ophthalmology(English edition) 2014年第2期7卷 251-255页

作者： Haider R.Cheema ahmed Al Habash essam Al-Askar Royal College of Surgeons in Ireland Dublin 1 Ireland Department of Ophthalmology University of Dammam Dhahran Eye Specialist Hospital

AIMTo report the visual outcome based on various patterns of optical coherence tomography (OCT) morphology in diabetic macular edema (DME), following treatment with anti-VEGF intravitreal bevacizumab (IVB) injection.

关键词： optical coherence tomography diabetic macular edema intravitreal injection bevacizumab