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Cooling and lubrication techniques in grinding:A state-of-the-art review,applications,and sustainability assessment

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Chinese Journal of Aeronautics 2023年第7期36卷 76-113页

作者： ahmed Mohamed Mahmoud IBRAHIM Wei LI abdel-Hamid ISMAIL MOURAD Mohamed A.E.OMER Fadl A.ESSA ahmed Mustafa abd EL-NABY Mohammad S.Al SOUFI Muhammad F.EZZAt Ammar ElSHEIKH College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China Production Engineering and Mechanical Design Department Faculty of EngineeringMinia UniversityEl Minya 61519Egypt Mechanical and Aerospace Engineering Department College of EngineeringUnited Arab Emirates UniversityAl-Ain 15551United Arab Emirates Department of Production Engineering and Mechanical Design Faculty of EngineeringTanta UniversityTanta 31527Egypt Mechanical Engineering Department Faculty of EngineeringKafrelsheikh UniversityKafrelsheikh 33516Egypt Mechanical Engineering Department College of Engineering and Islamic ArchitectureUmm Al-Qura UniversityMakkah 24231Saudi Arabia Mechanical Engineering Department Faculty of EngineeringUniversity of AlbertaEdmonton T6G 2R3Canada Automotive and tractors Engineering Department Faculty of EngineeringMinia UniversityEl Minya 61519Egypt tokyo Institute of technology Tokyo 152-8550Japan

Grinding technology is an essential manufacturing operation,in particular,when a component with a superfinishing and an ultra-resolution is *** the required strict quality checklist with maintaining a high level of productivity and sustainability is a substantive *** recent paper outlines the lubrication and cooling technologies and mediums that are used for ***,it provides a basis for a critical assessment of the different lubrication/cooling techniques in terms of machining outputs,environmental impact,hygiene effect,***,the paper put light on the sustainability of different cooling/lubrication *** sustainability of machining aims to get the product with the best accuracy and surface quality,minimum energy consumption,low environmental impact,reasonable economy,and minimum effect on worker’s *** paper revealed that despite some cooling/lubrication mediums like mineral oils and semisynthetic,afford sufficient lubrication or cooling,they have a significant negative impact on the environment and public *** the other hand,emulsions can overcome environmental problems but the economy and the energy consumption during grinding are still a matter of *** and vegetable oils are considered eco-friendly oils,but they suffer from a lack of thermal stability which affects their ability of efficiently *** the cooling medium with the lowest amount can achieve the goal of the economy but it may be reflected negatively on the ***,cryogenic lubrication doesn’t provide sufficient lubrication to reduce friction and hence energy *** research described in the paper is such a comprehensive compilation of knowledge regarding the machinability and machining performance under different cooling and lubrication systems that it will aid the next generation of scientists in identifying current advancements as well as potential future directions of research on ecolo

关键词： Cryogenic cooling Dry lubrication Minimum quantity lubrication Precision grinding Solid lubrication Sustainable machining Vegetable oils

A magneto -thermo-elastic problem for a half-space without energy dissipation subjected to rotation and gravity field

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Journal of Ocean Engineering and Science 2019年第1期4卷 55-63页

作者： A.M.abd-Alla S.M.Abo-Dahab S.M.ahmed M.M.Rashid Faculty of Science Mathematics DepartmentSohag UniversityEgypt Faculty of Science Mathematics DepartmentSouth Valley UniversityQena 83523Egypt Faculty of Science Mathematics DepartmentTaif University888Saudi Arabia Faculty of Science Mathematics DepartmentAl-Arish UniversityEgypt

the prime objective of the present paper is to analyze the effects of the rotation,magnetic field and gravity in a thermo-elastic half-space containing heat source on the boundary of the *** medium assumed under consideration is traction free,homogeneous,isotropic,as well as without energy *** normal mode analysis and eigenvalue approach technique are used to solve the resulting non-dimensional coupled *** comparisons for the physical quantities are established numerically and represented graphically in different cases with respect to the used effects.A comparative and remarkable study has been carried out through various graphs to deliberate the consequences of different parameter on the displacement components,stress components and temperature.

关键词： Green-Naghdi theory thermo-elasticity Energy dissipation Rotation Magnetic field Gravity field.

the Need to Autonomous Radiosounding System

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Journal of Geodesy and Geomatics Engineering 2015年第1期2卷 53-58页

作者： ahmed Saad abd-Elnaby the Egyptian Meteorological Authority Koubry El-Quobba Cairo 11784 Egypt

In recent years, the upper air radiosounding system based on GPS （global positioning system） is used as an effective method resulting to improving observation accuracy and helping in simplification of the ground equipment. GPS is used to calculate the pressure and wind speed and direction. the NAVStAR GPS has been developed by the Department of Defense of the United States, and the main purpose is to provide the military forces of the USA and its allies with a means to accurately determine their position, velocity and time, anywhere on the earth, at any time. Europe is now developing its own GPS, known as Galileo, which is independent of the USA GPS. As a result, many countries now are developing their own GPS system like Russia （GLONASS）, China （Compass）, India, and Japan. As a direct result, we can face the fact that each and every country will have its own GPS system and finally we come up with a crowded space. the INS （inertial navigation system） is a system that, once initialized （by acquiring the initial position, velocity, and orientation information）, becomes an autonomous navigation system providing 3-D position, velocity, and attitude information. So upper air observation can take advantage of this emerging technology by using this stand alone system （INS） in measuring wind speed and direction as well as measuring the altitude we can calculate the pressure.

关键词： Global positioning system inertial navigation system upper air observation.

Mud Wasps and Its Role in the Destruction of Ancient Buildings in Application to the temple of Isis in the temple of Dandara, Qena, Egypt and Methods of Prevention

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Journal of Building Construction and Planning Research 2022年第1期10卷 37-53页

作者： Elashmawy ahmed abd-Elkareem Hany ahmed Fouad Conservation Department Faculty of Archaeology South Valley University Qena Egypt Plant Protection Department Faculty of Agriculture Sohage University Shage Egypt

Mud wasps are one of the most important problems that many archaeological sites suffer from in Egypt, especially in southern Egypt. Wasp’s growth increases, especially on the surface of stones or on mud-brick buildings, which represents a major challenge to these archaeological sites. It works to hide the stone surfaces and archaeological inscriptions found on them in addition to that it works to damage the stone surfaces themselves through the nests that they build on these surfaces. It works on weakening the structure of sandstone and the study that included a study on mud wasps and Analysis of nests and studied through the use of various devices and methods, the damage and its nature have also been studied as a result of the presence of wasp nests and the reasons for their existence. Various treatment methods and the best appropriate methods for treating sandstone and stopping wasp activity have also been studied.

关键词： Mud Wasps Sandstone temple of Isis Destruction treatment

Is toxoplasmosis a potential risk factor for liver cirrhosis?

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Asian Pacific Journal of tropical Medicine 2015年第10期8卷 768-775页

作者： Abeer abd El-Rehim El-Henawy ahmed abdel-Razik Sahar Zakaria Dina Elhammady Niveen Saudy Manar Sobh Azab Department of Medical Parasitology Faculty of MedicineMansoura University Department of tropical Medicine Faculty of MedicineMansoura University Department of Clinical Pathology Faculty of MedicineMansoura University

Objective:to document toxoplasma gondii(***) antibody status in patients with liver disease,blood samples were taken from 180 hepatic patients and 180 healthy ***:toxoplasma IgG antibody was detected using enzyme-linked immunosorbent assay and histopathological assessment of liver biopsy MEtAVIR score was ***:*** IgG antibodies were found in 32.8%of patients and in 22.2%of controls(P=0.02).toxoplasma seropositivity was significantly associated with lymphadenopathy,history of blood transfusion and reflex impairment in *** hepatitis C virus(HCV)and chronic HCV-related cirrhosis groups compared to chronic HBV and chronic HBV-related cirrhosis groups expressed significantly higher prevalence of *** seropositivity(odds ratio(OR) =4;95%confidence interval(CI):1.3-12.6;P=0.013,OR=4.8;95%CI:1.5-14.9;P=0.006,respectively).Within the chronic HCV group,*** seropositivity significantly associated disease evolution as regards to MEtAVIR histopathological system for fibrosis and inflammation(OR=19.4;95%CI:2.3-165.2;P=0.0008,OR=0.29;95%CI:0.1-0.8;P=0.01,respectively).Albumin,international normalized ratio(INR) and platelets count were the laboratory parameters significantly altered in toxoplasma-positrvc chronic HCV patients(P=0.00 l,0.03,0.04,respectively).Child-Pugh scoring for cirrhosis in chronic HCV group placed the majority of seropositive patient in class C with significant statistical difference compared to Child A reference group(OR= 0.08;95%67:0.01-0.5;P=0.003).Conclusions:toxoplasma seropositivity was high in patients with cirrhosis and associated higher grades of inflammation and necrosis signifying disease evolution,suggesting that cirrhotic patients may thus form a risk group for toxoplasmosis.

关键词： toxoplasma gondii HBV HCV Liver cirrhosis MEtAVIR

Clinical correlates of common corneal neovascular diseases: a literature review

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International Journal of Ophthalmology(English edition) 2015年第1期8卷 182-193页

作者： Nizar Saleh abdelfattah Mohamed Amgad Amira A Zayed Hamdy Salem ahmed E Elkhanany Heba Hussein Nawal abd El-Baky Doheny Image Reading Center Doheny Eye InstituteUniversity of California Faculty of Medicine Cairo University Department of Surgery Mayo Clinic Faculty of Medicine University of Alexandria Department of Medical Oncology Mayo Clinic Faculty of Oral and Dental Medicine Cairo University Antibody Laboratory Protein Research DepartmentGenetic Engineering and Biotechnology Research InstituteCity for Scientific Research and Technology Applications

A large subset of corneal pathologies involves the formation of new vessels(neovascularization), leading to compromised visual acuity. this article aims to review the clinical causes and presentations of corneal neovascularization(CNV) by examining the mechanisms behind common CNV-related corneal pathologies, with a particular focus on herpes simplex stromal keratitis,contact lenses-induced keratitis and CNV secondary to keratoplasty. Moreover, we reviewed CNV in the context of different types of corneal transplantation and keratoprosthesis, and summarized the most relevant treatment available so far.

关键词： cornea neovascularization herpes simplex keratitis keratoplasty contact lens keratoprosthesis

the Prevalence and Clinical Manifestations of Co-Infection in Pediatric Infectious Mononucleosis: A Single-Centered, Retrospective Study

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Open Journal of Pediatrics 2024年第3期14卷 459-475页

作者： abdishakur abdukadir Muse Zakaria ahmed Mohamed Pu Yang Lihong Liao Bibek Dhar Shrestha Agness Nicholaus Kanusya Paul Mwale Youping Deng Dongchi Zhao Department of Pediatrics Zhongnan Hospital of Wuhan University Wuhan China Department of Ophthalmology Zhongnan Hospital of Wuhan University Wuhan China

Background: Recent studies indicate that the incidence of infectious mononucleosis (IM) has increased in China. Furthermore, it has been shown that children diagnosed with IM are prone to acquiring other pathogens. However, there is limited research on the prevalence of these co-infections in children with IM. thus, we conducted this study to determine the prevalence of coinfections and common pathogens, as well as to compare clinical manifestations in children with and without coinfections. Methods: this retrospective observational study was conducted at the Department of Pediatrics Zhongnan Hospital of Wuhan University, Wuhan, China, with data from January 2018 to January 2023. Data, including demographics, symptoms, lab results, and complications, were collected from the hospital’s electronic database and analyzed. the statistical analysis included descriptive statistics, independent samples t-tests and Mann-Whitney tests to compare the means of continuous variables. Statistical significance was determined by p-values less than 0.05. Results: the study involved 216 participants diagnosed with IM, predominantly males (61.6%) aged 0 - 4 years (50.9%). Coinfection was detected in 39.8% of children, with multiple pathogens present in 33.72% of these cases. Among coinfection cases, 40% occurred in children under 5 years old, and females made up 54.2% of these cases. Mycoplasma pneumoniae (MP) was the most prevalent pathogen, accounting for 18.1% of cases. Influenza B (IFB) and Influenza A (IFA) viruses were found in 16.7% and 13.9% of participants, respectively, indicating a notable occurrence of respiratory pathogen coinfections. Male gender, fever, tonsillopharyngitis, lower HGB levels, higher ESR, CRP, and ASt levels were correlated with coinfections. Conclusion: In summary, the study revealed a high prevalence of coinfections among children diagnosed with IM, particularly involving Mycoplasma pneumoniae and influenza viruses. these coinfections were notably

关键词： Prevalence Mononucleosis Coinfection Children Epstein-Barr Virus Features

transient elastography compared to liver biopsy and morphometry for predicting fibrosis in pediatric chronic liver disease: Does etiology matter?

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World Journal of Gastroenterology 2016年第16期22卷 4238-4249页

作者： Behairy El-Sayed Behairy Mostafa Mohamed Sira Khaled Refat Zalata El-Sayed Ebrahem Salama Mohamed ahmed abd-Allah Department of Pediatric Hepatology National Liver Institute Menofiya University Department of Pathology Faculty of Medicine Mansura University

AIM: to evaluate transient elastography (tE) as a noninvasive tool in staging liver fibrosis compared with liver biopsy and morphometry in children with different chronic liver ***: A total of 90 children [50 with chronic hepatitis C virus (HCV), 20 with autoimmune hepatitis (AIH) and 20 with Wilson disease] were included in the study and underwent liver stiffness measurement (LSM) using tE. Liver biopsies were evaluated for fibrosis, qualitatively, by Ishak score and quantitatively by fibrosis area fraction (FAF) using digital image analysis (morphometry). LSM was correlated with fibrosis and other studied variables using spearman correlation. A stepwise multiple regression analysis was also performed to examine independent factors associated with LSM. Different cut-off values of LSM were calculated for predicting individual fibrosis stages using receiver-operating characteristic curve. Cut-off values with optimal clinical performance (optimal sensitivity and specificity simultaneously) were ***: the majority of HCV group had minimal activity (80%) and no/mild fibrosis (72%). On the other hand, the majority of AIH group had mild to moderate activity (70%) and moderate to severe fibrosis (95%) and all Wilson disease group had mild to moderate activity (100%) and moderate to severe fibrosis (100%). LSM correlated significantly with both FAF and Ishak scores and the correlation appeared better with the latter (r = 0.839 vs 0.879, P th). LSM discriminated individual stages of fibrosis with high performance. Sensitivity ranged from 81.4% to 100% and specificity ranged from 75.0% to 97.2%. When we compared LSM values for the same stage of fibrosis, they varied according to the different etiologies. Higher values were in AIH (16.15 ± 7.23 kPa) compared to Wilson disease (8.30 ± 0.84 kPa) and HCV groups (7.43 ± 1.73 kPa). Multiple regression analysis revealed that Ishak fibrosis stage was the only ind

关键词： Autoimmune hepatitis Chronic hepatitis C Liver fibrosis Liver stiffness Morphometry Pediatrics transient elastography Wilson disease

Evaluation and management of acute pancreatitis

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World Journal of Clinical Cases 2019年第9期7卷 1006-1020页

作者： ahmed t Chatila Mohammad Bilal Praveen Guturu Department of Internal Medicine The University of Texas Medical Branch Division of Gastroenterology and Hepatology The University of Texas Medical Branch Division of Gastroenterology and Hepatology the University of Texas Medical Branch

Acute pancreatitis(AP) is one of the most common gastrointestinal causes for hospi-talization in the United States. In 2015, AP accounted for approximately390000 hospitalizations. the burden of AP is only expected to increase over *** recent advances in medicine, pancreatitis continues to be associated with a substantial morbidity and mortality. the most common cause of AP is gallstones, followed closely by alcohol use. the diagnosis of pancreatitis is established with any two of three following criteria:(1) abdominal pain consistent with that of AP;(2) Serum amylase and/or lipase greater than three times the upper limit of normal; and(3) Characteristics findings seen in crosssectional abdominal imaging. Multiple criteria and scoring systems have been established for assessing severity of AP. the cornerstones of management include aggressive intravenous hydration, appropriate nutrition and pain *** retrograde cholangiopancreatography and surgery are important aspects in management of acute gallstone pancreatitis. We provide a comprehensive review of evaluation and management of AP.

关键词： Acute pancreatitis Necrotizing pancreatitis Resuscitation Gallstone pancreatitis