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Chinese Physics B 2011年第10期20卷 362-367页

作者： ahmed Asad 吴江涛 State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University

We use non-equilibrium molecular dynamics simulations to calculate the self-diffusion coefficient, D, of a Lennard Jones fluid over a wide density and temperature range. the change in self-diffusion coefficient with temperature decreases by increasing density. For density ρ＊ = ρσ3 = 0.84 we observe a peak at the value of the self-diffusion coefficient and the critical temperature t＊ = kt/ε = 1.25. the value of the self-diffusion coefficient strongly depends on system size. the data of the self-diffusion coefficient are fitted to a simple analytic relation based on hydrodynamic arguments. this correction scales as N-α, where α is an adjustable parameter and N is the number of particles. It is observed that the values of a 〈 1 provide quite a good correction to the simulation data. the system size dependence is very strong for lower densities, but it is not as strong for higher densities. the self-diffusion coefficient calculated with non-equilibrium molecular dynamic simulations at different temperatures and densities is in good agreement with other calculations fronl the literature.

关键词： self-diffusion coefficient non-equilibrium molecular dynamic simulation Lennard Jonesfluid critical dynamics

Efficacy of using NRt thresholds in cochlear implants fitting,in prelingual pediatric patients

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Journal of Otology 2019年第4期14卷 128-135页

作者： ahmed Allam ahmed Eldegwi Department of Otolaryngology Mansoura University

Objective:to evaluate the efficacy of using neural response telemetry(NRt)thresholds in predicting behavioural thresholds during programming of cochlear implant in prelingual ***:Prospective study of 28 cochlear implants implanted with Nucleus 24 cochlear *** recorded NRt-thresholds on electrode numbers 1,6,11,16 and 22 of the electrode array in each patient,the neural response thresholds were correlated with the behavioural map after six months of programming the ***:the mean neural response telemetry level was significantly higher than the mean threshold level(t-level)but lower than the comfortable level(C-level)in all the electrodes *** levels could statistically significantly predict t behavioural levels and comfortable behavioural levels,ptrong positive correlation between comfortable thresholds and neural response telemetry level measurements and behavioural threshold level and neural response telemetry threshold ***:there is a useful role for neural response telemetry values in predicting the behavioural threshold and comfortable values in prelingual *** the NRt values with behavioural observations can improve the programming of cochlear implants.

关键词： NRt ECAP Behavioural levels Cochlear implant Programming

Microstructure and Mechanical Properties of Cold Metal transfer Welding Similar and Dissimilar Aluminum Alloys

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 715-724页

作者： ahmed Elrefaey Nigel G.Ross LKR Leichtmetallkompetenzzentrum Ranshofen GmbH Austrian Institute of Technology

Integrating structures made from aluminum alloys in automotive industry requires a large amount of joining. As a consequence, the properties of the joints have a significant influence on the overall performance of the whole structure. Robot cold metal transfer welding is a relatively new joining technique and has been used in this work to join 6082-t4 and 5182-O aluminum alloy sheets by using ER5356 and ER4043 filler metals. Microstructure characterization was performed by optical microscopy and energy dispersive X-ray spectroscopy, and the mechanical properties were measured by tensile and hardness tests. A correlation is made between welding variables, mechanical properties and the microstructure of welded joints. Results indicate that robot cold metal transfer welding provides good joint efficiency with high welding speed, good tensile strength, and ductility. Owing to the low heat input of robot cold metal transfer welding process, the heat affected zone microstructure was quite similar to base metals, and weld metal microstructure was the controlling factor of joint efficiency. the best performing were the 5182/5182 joints welded with ER5356 and these had mechanical property coefficients of 100%, 98%, and 85% for yield strength, ultimate tensile strength, and elongation, respectively.

关键词： Aluminum CMt Welding Microstructure tensile property

Biological silicon nanoparticles improve Phaseolus vulgaris L. yield and minimize its contaminant contents on a heavy metals-contaminated saline soil

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Journal of Environmental Sciences 2021年第8期33卷 1-14页

作者： Mohamed t.El-Saadony El-Sayed M.Desoky ahmed M.Saad Rania S.M.Eid Eman Selem ahmed S.Elrys Department of Agricultural Microbiology Faculty of AgricultureZagazig UniversityZagazig 44511Egypt Botany Department Faculty of AgricultureZagazig UniversityZagazig 44511Egypt Biochemistry Department Faculty of AgricultureZagazig UniversityZagazig 44511Egypt Agricultural Botany Department Faculty of AgricultureBenha University13736Egypt Botany and Microbiology Department Faculty of ScienceZagazig University44511Egypt Soil Science Department Faculty of AgricultureZagazig University44511ZagazigEgypt

the synthesis of biological silicon nano-particles(Bio-Si-NPs)is an eco-friendly and lowcost *** is no study focusing on the effect of Bio-Si-NPs on the plants grown on saline soil contaminated with heavy *** this study,an attempt was made to synthesis Bio-Si-NPs using potassium silica florid substrate,and the identified Aspergillus tubingensis AM11 isolate that separated from distribution systems of the potable water.A twoyear field trial was conducted to compare the protective effects of Bio-Si-NPs(2.5 and 5.0 mmol/L)and potassium silicate(10 mmol/L)as a foliar spray on the antioxidant defense system,physio-biochemical components,and the contaminants contents of Phaseolus vulgaris *** on saline soil contaminated with heavy *** findings showed that all treatments of Bio-Si-NPs and potassium silicate significantly improved plant growth and production,chlorophylls,carotenoids,transpiration rate,net photosynthetic rate,stomatal conductance,membrane stability index,relative water content,free proline,total soluble sugars,N,P,K,Ca2+,K+/Na+,and the activities of peroxidase,catalase,ascorbic peroxidase and superoxide oxide *** of Bio-Si-NPs and potassium silicate significantly decreased electrolyte leakage,malondialdehyde,H2 O2,O2·-,Na+,Pb,Cd,and Ni in leaves and pods of Phaseolus vulgaris *** to ***-Si-NPs were more effective compared to potassium *** of Bio-Si-NPs at the rate of 5 mmol/L was the recommended treatment to enhance the performance and reduce heavy metals content on plants grown on contaminated saline soils.

关键词： Bean Silicon Nano-silicon Aspergillus tubingensis AM11 Salinity Heavy metals

A comprehensive review on residual stresses in turning

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Advances in Manufacturing 2022年第2期10卷 287-312页

作者： Ammar H.Elsheikh S.Shanmugan t.Muthuramalingam Amrit Kumar thakur F.A.Essa ahmed Mohamed Mahmoud Ibrahim ahmed O.Mosleh Department of Production Engineering and Mechanical Design Facultyof EngineeringTanta UniversityTanta 31527Egypt Research Centre for Solar Energy Department of PhysicsKoneru Lakshmaiah Education FoundationVaddeswaramAndhra Pradesh 522502India Department of Mechatronics Engineering SRM Institute of Science and TechnologyChennai 603203India Department of Mechanical Engineering KPR Institute Engineering and TechnologyCoimbatoreTamilnaduIndia Department of Mechanical Engineering Faculty of EngineeringKafrelsheikh UniversityKafrelsheikh 33516Egypt Production Engineering and Mechanical Design Department Faculty of EngineeringMinia UniversityMinya 61519Egypt Shoubra Faculty of Engineering Benha UniversityBenhaEgypt

Residual stresses induced during turning processes can affect thequality and performance of machined products,depending on its direction and *** stresses can be highly detrimental as they can lead to creeping,fatigue,and stress corrosion *** final state of residual stresses in a workpiece depends on its material as well as the cutting-tool configuration such as tool geometry/coating,cooling and wear conditions,and process parameters including the cutting speed,depth-ofcut and ***,there have been disagreements in some literatures regarding influences of the abovementioned factors on residual stresses due to different cutting conditions,tool parameters and workpiece materials used in the specific *** review paper categorizes different methods in experimental,numerical and analytical approaches employed for determining induced residual stresses and their relationships with cutting conditions in a turning *** is presented for the effects of different cutting conditions and parameters on the final residual stresses state.

关键词： Residual stresses Machining turning:Process parameters

Elucidating the molecular basis of AtP-induced cell death in breast cancer: Construction of a robust prognostic model

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World Journal of Clinical Oncology 2024年第2期15卷 208-242页

作者： Hao-Ling Zhang Sandai Doblin Zhong-Wen Zhang Zhi-Jing Song Babu Dinesh Yasser tabana DahhamSabbar Saad Mowaffaq Adam ahmed Adam Yong Wang Wei Wang Hao-Long Zhang Sen Wu Rui Zhao Barakat Khaled Department of Biomedical Sciences Advanced Medical and Dental InstituteUniversiti Sains MalaysiaPenang 13200Malaysia School of Public Health Gansu University of Chinese MedicineLanzhou 730000Gansu ProvinceChina Clinical College of Chinese Medicine Gansu University of Chinese MedicineLanzhou 730000Gansu ProvinceChina Faculty of Pharmacy and Pharmaceutical Sciences University of AlbertaEdmonton AB T6G 2E1Canada Department of Science University of Technology and Applied Sciences RustaqRustaq 10 P.C.329Oman Department of Chemistry and Biochemistry San Diego State UniversitySan DiegoCA 92182United States Department of Pathology Center Gansu University of Chinese MedicineLanzhou 730000Gansu ProvinceChina College of Acupuncture-moxibustion and tuina Gansu University of Chinese MedicineLanzhou 730000Gansu ProvinceChina Universiti Sains Malaysia Advanced Medical and Dental InstitutePenang 13200Malaysia Department of Biomedical Science Universiti Sains MalaysiaPenang 13200Malaysia

BACKGROUND Breast cancer is a multifaceted and formidable disease with profound public health *** demise mechanisms play a pivotal role in breast cancer pathogenesis,with AtP-triggered cell death attracting mounting interest for its unique specificity and potential therapeutic *** to investigate the impact of AtP-induced cell death(AICD)on breast cancer,enhancing our understanding of its *** the foundational genes orchestrating AICD mechanisms were extracted from the literature,underpinning the establishment of a prognostic ***,a microRNA(miRNA)prognostic model was constructed that mirrored the gene-based prognostic *** between high-and low-risk cohorts within mRNA and miRNA characteristic models were scrutinized,with the aim of delineating common influence mechanisms,substantiated through enrichment analysis and immune infiltration *** the mRNA prognostic model in this study encompassed four specific mRNAs:P2X purinoceptor 4,pannexin 1,caspase 7,and cyclin *** miRNA prognostic model integrated four pivotal miRNAs:hsa-miR-615-3p,hsa-miR-519b-3p,hsa-miR-342-3p,and hsa-miR-324-3p.B cells,CD4+t cells,CD8+t cells,endothelial cells,and macrophages exhibited inverse correlations with risk scores across all breast cancer ***,Kyoto Encyclopedia of Genes and Genomes analysis revealed that genes differentially expressed in response to mRNA risk scores significantly enriched 25 signaling pathways,while miRNA risk scores significantly enriched 29 signaling pathways,with 16 pathways being jointly *** Of paramount significance,distinct mRNA and miRNA signature models were devised tailored to AICD,both potentially autonomous prognostic *** study's elucidation of the molecular underpinnings of AICD in breast cancer enhances the arsenal of potential therapeutic tools,offering an unparalleled window for innovative ***,this paper revea

关键词： AtP-induced cell death mRNA miRNA Prognostic model Breast cancer

Inertial sensors technologies for navigation applications:state of the art and future trends

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Satellite Navigation 2020年第1期1卷 9-29页

作者： Naser El-Sheimy ahmed Youssef Mobile Multi-sensor Systems Research team Department of Geomatics EngineeringUniversity of Calgary2500 University Drive N.WCalgaryAB T2N 1N4Canada

Inertial navigation represents a unique method of navigation,in which there is no dependency on external sources of *** opposed to other position fixing navigation techniques,inertial navigation performs the navigation in a relative sense with respect to the initial navigation state of the moving ***,inertial navigation systems are not prone to jamming,or *** navigation systems have developed vastly,from their occurrence in the 1940s up to *** accuracy of the inertial sensors has improved over time,making inertial sensors sufficient in terms of size,weight,cost,and accuracy for navigation and guidance *** the past few years,inertial sensors have developed from being purely mechanical into incorporating various technologies and taking advantage of numerous physical phenomena,from which the dynamic forces exerted on a moving body could be computed ***,the evolution of inertial navigation scheme involved the evolution from stable-platform inertial navigation system,which were mechanically complicated,to computationally demanding strap-down inertial navigation *** sensory technologies have provided highly accurate inertial sensors,at smaller ***,the vibratory inertial navigation technologies enabled the production of Micro-electro-machined inertial sensors that are extremely low-cost,and offer extremely low size,weight and power consumption,making them suitable for a wide range of day-to-day navigation ***,advanced inertial sensor technologies have been introduced to the industry such as nuclear magnetic resonance technology,coldatom technology,and the reintroduction of fluid-based inertial *** another note,inertial sensor errors constitute a huge research aspect in which it is intended for inertial sensors to reach level in which they could operate for substantially long operation times in the absence of updates from aiding sensors,which would be a hug

关键词： Gyroscopes Accelerometers Optical inertial sensors Micro-electro-machined Fluid-based inertial sensors Stochastic modeling

Control of Wave Propagation and Effect of Kerr Nonlinearity on Group Index

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Communications in theoretical Physics 2013年第7期60卷 87-92页

作者： Hazrat Ali Ziauddin Iftikhar ahmed Department of Physics University of Malakand Department of Physics COMSATS Institute of Information Technology

We use four-level atomic system and control the wave propagation via forbidden decay rate. the Raman gain process becomes dominant on electromagnetically induced transparency (EIt) medium by increasing the forbidden decay rate via increasing the number of atoms [G.S. Agarwal and t.N. Dey, Phys. Rev. A 74 (2005) 043805 and K. Harada, t. Kanbashi, and M. Mitsunaga, Phys. Rev. A 73 (2006) 013803]. the behavior of wave propagation is dramatically changed from normal (subluminal) to anomalous (superluminal) dispersion by increasing the forbidden decay rate. the system can also give a control over the group velocity of the light propagating through the medium via Kerr field.

关键词： normal and anomalous dispersion Kerr field group index

SMILE intraoperative complications: incidence and management

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International Journal of Ophthalmology(English edition) 2019年第2期12卷 280-283页

作者： Abdelmonem M Hamed Mohamed Amin Heikal tarek t.Soliman ahmed Daifalla Khaled E Said-ahmed Benha University Department of Ophthalmology Menoufia University Department of Ophthalmology

AIM: to report the intraoperative complications associated with small incision lenticule extraction(SMILE) and their management. MEtHODS: this was a retrospective consecutive interventional clinical study, carried out on patients with myopia and myopic astigmatism, who underwent SMILE procedure. type of intraoperative complications and their management were recorded. RESULtS: Our study comprised 282 eyes of 141 patients who were enrolled for SMILE surgeries. the intraoperative complications included lost vacuum(18 eyes, 6.38%), treatment decentration(6 eyes, 2.12%), wound bleeding(21 eyes, 7.45%), incomplete bubble separation(black islands)(3 eyes, 1.06%), the epithelial defects(15 eyes, 5.32%). Incision tear(27 eyes, 9.57%), lenticule adherence to the cap(6 eyes, 2.12%), and cap perforation occurred in 2 eyes(0.7%). CONCLUSION: Although SMILE is a promising technique for the correction of myopia and myopic astigmatism with predictable, efficient, safe refractive and visual outcomes, complications can occur. However, most of them are related to inexperience and are included in the learning curve of the technique. More studies with a bigger number of eyes are required to efficiently evaluate the intraoperative complications and standardize their management strategies.

关键词： femtosecond laser intraoperative complication small incision lenticule extraction

Safety of gastrointestinal endoscopy in patients with acute coronary syndrome and concomitant gastrointestinal bleeding

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World Journal of Clinical Cases 2021年第5期9卷 1048-1057页

作者： ahmed A Elkafrawy Mohamed ahmed Mohammad Alomari ahmed Elkaryoni Kevin F Kennedy Wendell KClarkston Donald R Campbell Digestive Disease and Surgery Institute Cleveland Clinic FoundationClevelandOH 44195United States Internal Medicine University of Missouri Kansas City School of MedicineKansas CityMO 64108United States Department of Gastroenterology and Hepatology Cleveland Clinic FloridaWestonFL 33331United States Division of Cardiovascular Medicine Loyola University Medical Center and Stritch School of MedicineMaywoodIL 60153United States Mid America Heart Institute Saint Luke's Health SystemKansas CityMO 64111United States Department of Gastroenterology Saint Luke's Hospital/University of Missouri Kansas CityKansas CityMO 64111United States

BACKGROUND Gastrointestinal bleeding(GIB)is a major concern in patients hospitalized with acute coronary syndrome(ACS)due to the common use of both antiplatelet medications and *** evaluating the safety of gastrointestinal endoscopy(GIE)in ACS patients with GIB are limited by their relatively small size,and the focus has generally been on upper GIB and esophago-gastroduodenoscopy(EGD)*** to evaluate the safety profile and the hospitalization outcomes of undergoing GIE in patients with ACS and concomitant GIB using the national database for hospitalized patients in the United *** the Nationwide Inpatient Sample database was queried to identify patients hospitalized with ACS and GIB during the same admission between 2005 and *** International Classification of Diseases Code,9th Revision Clinical Modification was utilized for patient *** were further classified into two groups based on undergoing endoscopic procedures(EGD,small intestinal endoscopy,colonoscopy,or flexible sigmoidoscopy).Both groups were compared regarding demographic information,outcomes,and *** analysis was conducted to identify factors associated with mortality and prolonged length of ***-square test was used to compare categorical variables,while Student’s t-test was used to compare continuous *** analyses were performed using SAS 9.4(Cary,NC,United States).RESULtS A total of 35612318 patients with ACS were identified between January 2005 and December 2014.269483(0.75%)of the patients diagnosed with ACS developed concomitant GIB during the same *** least one endoscopic procedure was performed in 68%of the patients admitted with both ACS and *** who underwent GIE during the index hospitalization with ACS and GIB had lower mortality(3.8%)compared to the group not undergoing endoscopy(8.6%,Pter length of stay(LOS)was observed in patients who underwent GIE(mean 6.59±7.81 d)co

关键词： Gastrointestinal endoscopy Gastrointestinal bleeding Acute coronary syndrome Safety Outcomes Mortality