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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

Prospective Study of Holter Monitoring in Pediatric Patients at Sohag University Hospital

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World Journal of Cardiovascular Diseases 2020年第7期10卷 460-472页

作者： Safaa Ali Feby Sobhy mohamed abd el aal Shiamaa Mahamoud Sohag University Hospital Sohag Egypt

Background: To estimate the various indications, values and misuses of Holter monitoring in the diagnosis and management of pediatric patients. Methods: The study was a prospective observational study, carried out at Pediatric Arrhythmia Clinic and at PICU of Sohag University Hospital over two years from 09/2017 to 09/2019. It encountered 80 pediatric patients (34 females), their age ranged from 29 days to 15 years with mean age of 6.18 years. All patients were subjected to echocardiography, 12 leads ECG and holter monitoring for 24 hours. Minimum, mean, maximum heart rate, rhythms and corrected QT were evaluated. Indications of Holter examination, its abnormalities were analyzed, also its positive diagnosis and management were defined. Results: Palpitations and syncopy were the main indications for holter examination 22 (27.50%) patients for each, abnormal examination in 17 (21.25%), chest pain in 13 patients (16.25%) and cardiomyopathy (7.5%) (one with Hypertrophic Cardiomyopathy and five with Dilated Cardiomyopathy). There were 50 (62.50%) patients had abnormalities in Holter recordings. The highest contribution to diagnosis was in cardiomyopathy (83.3%) where the most common abnormalities were ventricular tachycardia (50%) and ventricular premature beats in (33.3%). An abnormal ECG was significantly associated with a higher diagnostic yield (p = 0.0001). Conclusion: The most important indications for Holter monitoring include palpitations, syncope, abnormal physical exam findings, chest pain, and cardiomyopathy. Holter monitoring is an extremely important tool in the assessment of patients with dilated cardiomyopathy. HM detects serious arrhythmias to identify patients who are at increased risk for

关键词： Holter Pediatric Arrhythmia ECG

Revision on the Recent Diagnostic Strategies of Fungal Infections

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Open Journal of Medical Microbiology 2017年第1期7卷 29-40页

作者： Amina Mostafa abd el-aal Noha el-Mashad Al-Shaymaa Nasr mohamed Department of Clinical Pathology Faculty of Medicine Mansoura University Mansoura Egypt Department of Clinical Pathology Aga Central Hospital Mansoura Egypt

Many invasive fungal diseases have no characteristic signs or symptoms, and may give negative blood cultures;therefore, clinician may decide to start empirical antifungal therapy particularly in high risk patient (e.g., hematopoietic stem cell transplant, solid organ transplant, and AIDS patients). This increases the incidence of appearance of resistant fungal strains to antifungal drugs. Traditional methods for diagnosis such as wet mount examination and microbiological cultures remain the gold standard methods for fungal disease diagnosis. However, they are time-consuming, insensitive, and have a limited impact on clinical decision-making. Significant progress has recently achieved in diagnostic tools of fungal disease. Antigen and antibody based assays, molecular techniques, and MALDI TOF spectrometry technique and nanotechnology offer more rapid, sensitive and accurate results.

关键词： Fungal Infections Conventional Diagnostic Techniques Mannan MALDI-TOF MS Molecular Diagnostic Techniques

Helicobacter pylori may be an initiating factor in newly diagnosed ulcerative colitis patients: A pilot study

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World Journal of Clinical Cases 2018年第13期6卷 641-649页

作者： Loai Mansour Ferial el-Kalla abdelrahman Kobtan Sherief abd-elsalam mohamed Yousef Samah Soliman Lobna Abo Ali Walaa elkhalawany ibrahim Amer Heba Harras Maha M Hagras mohamed elhendawy Tropical Medicine and Infectious Diseases Department Faculty of Medicine Tanta University Hepatology and Gastroenterology Department Faculty of Medicine Kafr El-Sheikh University Pathology Department Faculty of Medicine Tanta University Clinical Pathology Department Faculty of Medicine Tanta University

AIM To directly visualize Helicobacter pylori(H. pylori) by the highly sensitive and specific technique of immunohistochemical staining in colonic tissue from patients newly diagnosed with ulcerative colitis(UC).METHODS Colonoscopic biopsies from thirty patients with newly diagnosed UC and thirty controls were stained with Giemsa stain and immunohistochemical stain for detection of H. pylori in the colonic tissue. Results were confirmed by testing H. pylori Ag in the stool then infected patients were randomized to receive either anti H. pylori treatment or *** Twelve/30(40%) of the UC patients were positive for H. pylori by Giemsa, and 17/30(56.6%) by immunohistochemistry stain. Among the control group 4/30(13.3%) and 6/30(20 %) were positive for H. pylori by Giemsa and immunohistochemistry staining respectively. H. pylori was significantly higher in UC than in controls(P = 0.04 and 0.007). All Giemsa positive patients and controls were positive by immunohistochemical stain. Four cases of the control group positive for H. pylori also showed microscopic features consistent with early *** H. pylori can be detected in colonic mucosa of patients with UC and patients with histological superficial ulcerations and mild infiltration consistent with early UC. There seems to be an association between UC and presence of H. pylori in the colonic tissue. Whether this is a causal relationship or not remains to be discovered.

关键词： Ulcerative colitis Immunohistochemical staining Inflammatory bowel disease Helicobacter pylori Giemsa stain

Efficient Hardware Design of a Secure Cancellable Biometric Cryptosystem

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Intelligent Automation & Soft Computing 2023年第4期36卷 929-955页

作者： Lamiaa A.Abou elazm Walid el-Shafai Sameh ibrahim mohamed G.Egila H.Shawkey mohamed K.H.elsaid Naglaa F.Soliman Hussah Nasser AlEisa Fathi E.abd el-Samie Department of Microelectronics Electronics Research InstituteAlnozhaEgypt Department of electronics and electrical Communications Engineering Ain Shams UniversityCairoEgypt Department of electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Security Engineering Laboratory Department of Computer SciencePrince Sultan UniversityRiyadh 11586Saudi Arabia Department of Information Technology College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia

Biometric security is a growing trend,as it supports the authentication of persons using conﬁdential biometric *** of the transmitted data in multi-media systems are susceptible to attacks,which affect the security of these *** systems provide sufﬁcient protection and privacy for *** recently-introduced cancellable biometric recognition systems have not been investigated in the presence of different types of *** addition,they have not been studied on different and large biometric *** point that deserves consideration is the hardware implementation of cancellable biometric recognition *** paper presents a suggested hybrid cancellable biometric recognition system based on a 3D chaotic *** rationale behind the utilization of the 3D chaotic cryptosystem is to guarantee strong encryption of biometric templates,and hence enhance the security and privacy of *** suggested cryptosystem adds signiﬁcant permutation and diffusion to the encrypted biometric *** introduce some sort of attack analysis in this paper to prove the robustness of the proposed cryptosystem against *** addition,a Field Programmable Gate Array(FPGA)implementation of the pro-posed system is *** obtained results with the proposed cryptosystem are compared with those of the traditional encryption schemes,such as Double Random Phase Encoding(DRPE)to reveal superiority,and hence high recogni-tion performance of the proposed cancellable biometric recognition *** obtained results prove that the proposed cryptosystem enhances the security and leads to better efﬁciency of the cancellable biometric recognition system in the presence of different types of attacks.

关键词： Information security cancellable biometric recognition systems cryptanalysis 3D chaotic map encryption FPGA

Assessment of EEG Changes in Neonatal Sepsis at Al-Zahraa University Hospital’s NIC Unit

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Open Journal of Pediatrics 2020年第3期10卷 493-503页

作者： Sara Tarek mohamed mohamed Zeinab Farag Oshaiba Marwa el-Hady abd el Moneim Asmaa abd el Wakeel ibrahim Student Hospital Al-Azhar University Cairo Egypt Pediatric and Neonataology Department of Al Zahraa University Hospital Faculty of Medicine for Girls Al-Azhar University Cairo Egypt

Background: EEG is one of the most sensitive instrumental techniques for identifying sepsis-related neurological complications and a valuable tool in the ICU when clinical assessment is difficult. Aim of the Study: To detect EEG changes in neonates with evidence of sepsis. Patients and Methods: This was a prospective observational study for detecting EEG changes in cases of proven neonatal sepsis. This study was conducted at the NICU of Al Zahraa University Hospital for a period from October 2019 to March 2020. Our studied neonates were 50. This study included full-term newborns (37 to 42 weeks of gestational age) with clinical and laboratory evidence of sepsis (early and late onset). Neonatal birth asphyxia, jaundice, congenital malformations, suspected inborn error of metabolism and neonates electrolytes disturbances were excluded from the study. We record EEG changes during 20 min By an electroencephalogram (EEG) with abioelectric amplifier (Deltamed, Bourgogne), (Philips) Screen. Results: Among our studied neonates (neonates with evidence sepsis), 44.0% developed clinical seizures, 81% of the seizures group had abnormal EEG, 35.7% of No seizures group had abnormal EEG. Among our studied neonates, 56% had abnormal EEG EEG abnormalities were as follow, 26%/ had low voltage, 30% had spikes, 22% had sharp waves. Conclusion: About 35% (one third) of neonates who didn’t develop clinical se

关键词： Background Abnormalities electroencephalogram Neurological Complication Sepsis Spike Seizures

Impact of COVID-19 infection during pregnancy on maternal and fetal outcomes

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Reproductive and Developmental Medicine 2023年第2期7卷 108-114页

作者： mohamed elsibai Anter Nasser Kamal abd el-aal mohamed abd Allah Rezk Hussein Fahmy Moawad Ahmed Tharwat Abudakika Obstetrics and Gynecology Department Faculty of MedicineElkom CityMenoufia UniversityMenoufiaEgypt Resident of Obstetrics and Gynecology at al-Bagour General Hospital al-Bagour CityMenoufiaEgypt

Objectives:The objective of this study is to assess the impact of coronavirus disease 2019(COVID-19)infection during pregnancy on maternal and fetal outcome in relation to gestational ***:This retrospective study was conducted between May 2020 and July ***-five women infected with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and hospitalized at a quarantine hospital were ***-four women received prenatal care at the hospital until delivery,while 31 dropped out from the study due to COVID-19 recovery and discharge before ***:COVID-19 was found in 83%of the pregnant women after 20 weeks of *** most common symptoms were cough and *** complications included severe pneumonia and *** maternal mortality rate was 9.2%.Premature rupture of membranes and severe hypertension during labor affected nearly 9%of the pregnant women who completed prenatal care until delivery at the *** labor occurred at a rate of 38.2%.There were seven(20.8%)stillbirths and two cases of infant ***:Hospitalized pregnant women who have coronavirus infection,lymphopenia,and a high C-reactive protein level were at a higher risk of developing severe illness,which can lead to maternal and neonatal complications.

关键词： COVID-19 Hospitals Infant Quarantine Pregnancy outcome Prenatal care Women

Utilization of Egyptian Ilmenite Ore for Steel Surface Preparation in Petroleum Field

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Engineering（科研） 2011年第8期3卷 802-809页

作者： Mahmoud ibrahim abdou mohamed abd el-Fattah Moustafa Hany el- Sayed Ahmed Hamada abd el-Wahab Production Department Egyptian Petroleum Research Institute (EPRI) Cairo Egypt

The construction of gas and oil plants include many items such as steel structures, equipments, piping, tanks and vessels at different conditions such as offshore, onshore, above and underground shall be protected against corrosion by coating. The protective value of a coating system is proportional to the surface preparation;the objectives of the surface preparation are the surface cleanliness and the surface profile of the substrate. The surface preparation is usually achieved by blast cleaning using different types of abrasive. Due to its high hardness and low cost, silica sand has been used extensively for impact abrasion. It is, however, very brittle with most grain disintegrating on impact, causing excessive levels of siliceous dust which is a major health hazard and causes serious environmental pollution. Consequently, it has been banned as impact abrasive material in most countries around the world. Considerable research has been done in the last twenty years to find an impact abrasive material as hard as silica and that respects. So it was important to search for sand substitution among the local abundant minerals in Egypt. Waste product obtained from ilmenite ore extracted from the mine was found to be the most suitable alternative abrasive. This work shows the abrasive types, the occurrence of the ilmenite ore. The chemical properties, physical properties and microscopic examination of the waste were investigated. The obtained result indicates that, the waste product obtained from ilmenite ore can be utilized for abrasion as sand substitution.

关键词： Blast Cleaning Material Ilmenite Abrasive Material Surface Cleanliness Surface Profile and Surface Preparation.

Preparation and Characterization of Hot-Pressed and Sintered BiPbSrCaCuO Superconductor

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New Journal of Glass and Ceramics 2012年第2期2卷 75-84页

作者： mohamed mohamed ibrahim Nassar Mahmoud Megahid Mostafa mohamed abd el-Raheem Sayed Mohammed Khalil Department of Physics Faculty of Science Sohag University Sohag Egypt Department of Physics Faculty of Science Taif University Taif KSA Department of Physics Faculty of Science Ummulqura University Mekka KSA

Powder compacts of the system Bi2–xPbxSr2Ca2Cu3Oy with 0 ≤ x ≤ 0.5 molar ratio using both techniques;isothermal hot pressing and the solid state reaction (sintering). The XRD of the hot pressed powder compacts of the nominal compositions Bi2–xPbxSr2Ca2Cu3Oy showed 2212 and 2223 phases. The resistivity temperature variations belonging to the composition Bi1.8Pb0.2Sr2Ca2Cu3Oy showed metal-superconducting transition at Tons = 143 K for the annealed sample for 24 h. The annealed nominal composition Bi1.5Pb0.5Sr2Ca2Cu3Oy for 18 h showed metal to superconducting transition at 80 K.

关键词： electrical Resistivity Superconductors Hot Pressing Sintering