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International Journal of Ophthalmology(English edition) 2020年第1期13卷 129-134页

作者： Amr Mounir Engy Mohamed Mostafa hatem Ammar Osama Ali Mohammed Alahmady Hamad Alsmman Mahmoud Mohamed Farouk Mohamed Gamal Elghobaier Department of Ophthalmology Sohag Faculty of MedicineSohag UniversitySohag 82524Egypt Egyptian Police Hospitals Cairo 11765Egypt

AIM: To evaluate the safety and efficacy of transepithelial photorefractive keratectomy(t-PRK) with adjuvant mitomycin C(MMC) versus femtosecond laser assisted keratomileusis(Femto-LASIK) in correction of high ***: Prospective randomized comparative study including 156 eyes of 156 patients with high myopia and a spherical equivalent refraction(SER) <-6.00 D. They were divided randomly into two groups: Group A included 72 eyes treated with t-PRK with adjuvant MMC and Group B included 84 eyes treated with Femto-LASIK. Visual acuity, SER, corneal topography, pachymetry and keratometry were assessed for 12 mo ***: The preoperative mean SER was-8.86±1.81 and-9.25±1.70 D in t-PRK MMC group and Femto-LASIK respectively(P=0.99) which improved to-0.65±0.43 D and-0.69±0.50 D at 12 mo follow up. Mean SER remained stable during the 12 mo of follow-up, with no statistically significant difference between the two groups(P=0.64). In t-PRK MMC group, only six eyes needed retreatment after six months of follow up. And two eyes showed haze(one reversible haze grade 2, while the other had dense irreversible haze grade 4).CONCLUSION: t-PRK MMC provides safe and satisfactory visual outcomes and acceptable risk as Femto-LASIK in patients with high myopia.

关键词： transepithelial photorefractive keratectomy femtosecond laser assisted keratomileusis high myopia corneal haze Egypt

Interevent times estimation of major and continuous earthquakes in Hormozgan region based on radial basis function neural network

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Geodesy and Geodynamics 2016年第1期7卷 64-75页

作者： M.R.Mosavi M.Kavei M.Shabani Y.hatem Khani Department of Electrical Engineering Iran University of Science and Technology Department of Physics University of Hormozgan Department of Electrical Engineering University of Imam Khomeini Marine Sciences

This paper presents a new method to estimate the time of important earthquakes in Hormozgan region with magnitude greater than 5.5 based on the Radial Basis Function （RBF） Neural Network （NN） models. Input vector to the network is composed of different seisrnicity rates between main events that are calculated in convenient and reliable way to create optimized training methods. It helps network with a limited number of training data to estimation. It is common for earthquakes modeling by data-driven methods in this case. In addition, the proposed method is combined with Rosenberg cluster method to remove aftershocks events from the history of catalog for NN to better process the data. The results show that created RBF model successfully estimates the interevent times between large and sequence earthquakes that can be used as a tool to predict earthquake, so that comparison with other NN structure, for example Multi- Layer Perceptron （MLP） NN, reveals the superiority of the proposed method. Because of superiority proposed method has higher accuracy, lower costs and simpler network structure.

关键词： Interevent timesRadial basis functionNeural networksEarthquakes

Investigation of the Fiber Central Dip Refractive Index Profile Using Laser-Lens Fiber Interferometer

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材料科学与工程（中英文B版） 2011年第2期1卷 148-156页

作者： hatem El-Ghandoor hatem El-Hennawi Fouad EI-Diasty Mona A. Soliman Physics Department Faculty of Science Ain Shams University Abbasia Cairo 11566 Egypt

In this paper, a new technique has been applied to study the central dip refractive index in optical fibers. Laser lens-fiber interference method is used for calculating the refractive index of graded-index optical fiber (GRIN) from its transverse interference pattern. The transverse interference fringe pattern through an optical fiber using a sheet of light is applied to get the refractive index profile. The light sheet is divided into two parts; the first is refracted through the fiber while the second is used as a reference beam. Interference pattern will be obtained between these two rays displaying the refractive index variation along the fiber radius. The fringe shift of such interference pattern has been measured and used to calculate the deflection angle of light refracted by the fiber and the clad, core and central dip. A mathematical expression for the optical path length has been derived and used to describe experimental intensity of interference fringes. The accuracy in the measured refractive index is of the order 10-6. A CCD camera is used to record the transverse interference pattern from the fiber. The optical fiber is not immersed in a matching liquid as used in different techniques. An equation is derived to calculate the refractive index profile at different positions across the fiber cross section in terms of the corresponding deflection angle and is verified experimentally. Different advanced applications of optical fibers are depending basically on the fiber structure and on its index profile. Therefore precise and accurate determination of these profiles is needed.

关键词：光纤折射率光纤干涉透镜光纤中央激光光学纤维折射率分布干扰模式

Risk Assessment and Risk Perception of Coronary Heart Disease in Gaza Strip, Palastine

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Health 2014年第21期6卷 2883-2893页

作者： hatem Dabbak Mostafa A. Arafa University College of Ability Development—Gaza Palestine Red Crescent Society Uro-Oncology Research Chair College of Medicine King Saud University Riyadh KSA

Aim: The aim of the present study was to estimate the prevalence of coronary heart diseases (CHD) risk factors among Ghaza (Palastine) university students, to assess the CHD risk among them using a suitable scoring system and to identify how they perceive their risk of CHD. Methods: During the period from May 2008 to May 2009, 501 students were involved. Participants were subjected to the following activities;self administered questionnaire: including socio-demographic data, medical history of chronic diseases, family history about CHD, knowledge and perception of risk factors, anthropometric measurements in addition to laboratory testing. Results: The mean age was 20.8 ± 2.07 years;54% were females. The prevalence of hypertension and DM was 3.6% and 0.4% while it was 2.6% for hypercholesterolemia. The mean levels of LDL-C (88 mg/dl vs 85.5 mg/dl) and HDL-C (52.4 mg/dl vs 42.6 mg/dl) were higher among females than among males. Smoking was more prevalent among males than among females (33.1% vs 1.7%) with a total prevalence of 19%. Overweight and obesity were more prevalent among males (30.7% vs 22.5% and 9.6% vs 5.6%). In contrast to risk perception female students tend to be more knowledgeable than males with regards to different aspects of CHD. The overall level of perceived risk was moderate. Logistic regression analysis revealed that age and sex were associated significantly by higher level of total perception (p < 0.05). Conclusion: Health education and health promotion programs should be implemented and integrated within the primary health care sectors and directed to university students before admission. Further research needed to be implemented on larger sample to test knowledge and perception of the public in regard to their risk for heart disease including school children and community so that education could be provided in a more focused manner.

关键词： Coronary Heart Diseases (CHD)

Comparison between Pt/TiO_2/Pt and Pt/TaO_X/TaO_Y/Pt based bipolar resistive switching devices

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Journal of Semiconductors 2016年第6期37卷 39-51页

作者： Patrick W.C.Ho Firas Odai hatem Haider Abbas F.Almurib T.Nandha Kumar Department of Electrical and Electronic Engineering University of Nottingham Malaysia Campus

Nonvolatile memories have emerged in recent years and have become a leading candidate towards replacing dynamic and static random-access memory *** this article,the performances of T1O_2 and TaO_2nonvolatile memristive devices were compared and the factors that make TaO_2 memristive devices better than T1O_2 memristive devices were ***_2 memristive devices have shown better endurance performances（10~8times more switching cycles） and faster switching speed（5 times） than TiO_2 memristive *** of TaO_2 memristive devices requires ~ 4.5 times less energy than TiO_2 memristive devices of a similar *** retention period of TaO_2 memristive devices is expected to exceed 10 years with sufficient experimental *** addition to comparing device performances,this article also explains the differences in physical device structure,switching mechanism,and resistance switching performances of TiO_2 and TaO_2 memristive *** article summarizes the reasons that give TaO_2 memristive devices the advantage over TiO_2 memristive devices,in terms of electroformation,switching speed,and endurance.

关键词： resistive switching devices TiO2 devices TaO2 devices non-volatile memory devices

Numerical Study of an Integrated Collector Storage Solar Water Heater

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材料科学与工程（中英文B版） 2011年第5期1卷 689-695页

作者： Monia Chaabane hatem Mhiri Philippe Bournot National Engineering School of Monastir Monastir Tunisia Mechanical Institute of Marseille 60 street Juliot Curie Technopole of Castle-Gombert 13453 Marseille Cedex 13 France

In this paper, we propose a numerical study of an integrated collector storage solar water heater. The numerical resolution of the governing equations was carried out using a commercial CFD code FLUENT 6.2 which is based on a finite volume method. The discussion is related firstly to the validation of the CFD model. Then, the effect of the absorber surface selectivity was investigated. The mean water temperature profile over time is studied for a day of May, from 6 am to 6 pm, to highlight this change’s effect on water heating process. Streamlines and temperature contours were also investigated for a cross section of the solar water heater. The effect of this change on the SWH efficiency was also studied.

关键词：太阳能热水器数值研究储存收集 CFD软件 FLUENT 温度分布有限体积法

Effect of Pressure on the Fracture of Compacted Argillaceous Particles

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Engineering（科研） 2012年第1期4卷 18-23页

作者： Mohamed Bouaziz Said Abid hatem Ksibi 不详

The compaction of granulated powder is a common forming process used in ceramic and pharmaceutical industries. Argillaceous particles are used as a model system to investigate granule failure during cold compaction. In this work both experimental and numerical investigations have been focused on the fracture in powder compacts. This includes studies of crack propagation and determination of operating conditions to avoid the green body fracture. In fact, axial compaction tests have been performed to determine material parameters for hardening. The numerical modelling is implemented using a finite element method based on the Van Mises criterion. Simulation examples are presented to dem- onstrate the ability of the model to compute the distribution of the relative stresses in porous media.

关键词： Cold Compaction Powder Technology Fracture Scraped Surface Cracking Cone Numerical Simulation

Weinstein Gabor Transform and Applications

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Advances in Pure Mathematics 2012年第3期2卷 203-210页

作者： hatem Mejjaoli Ahmedou Ould Ahmed Salem Department of Mathematics College of Education King Khalid University Mohayil Kingdom of Saudi Arabia Department of Mathematics College of Sciences King Faisal University Ahsaa Kingdom of Saudi Arabia

In this paper we consider Weinstein operator. We define and study the continuous Gabor transform associated with this operator. We prove a Plancherel formula, an inversion formula and a weak uncertainty principle for it. As applications, we obtain analogous of Heisenberg’s inequality for the generalized continuous Gabor transform. At the end we give the practical real inversion formula for the generalized continuous Gabor transform.

关键词： Weinstein Gabor Transform Practical Real Inversion Formula Kernel Reproducing Theory

Rare case of secondary hemophagocytic lymphohistiocytosis in a patient with disseminated histoplasmosis

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Pediatric Investigation 2023年第3期7卷 222-224页

作者： hatem Alzahrani Melanie Pancoast Kody Finstad Nicole Pele Francisca Fasipe Mohamed Elsaid Department of Pediatric Oncology King Faisal Specialist Hospital and Research Center MadinahRiyadhSaudi Arabia John Peter Smith Hospital Fort WorthTexasUSA School of Medicine University of MissouriSpringfieldMissouriUSA Department of Pediatric Mercy Children’s HospitalSpringfieldMissouriUSA Department of Pathology Mercy Children’s HospitalSpringfieldMissouriUSA Division of Hematology/Oncology Mercy Children’s HospitalSpringfieldMissouriUSA

To the editor:A previously healthy 3-month-old male presented to his pediatrician with an isolated fever for a few days.A complete blood count(CBC)revealed hemoglobin(Hb)81 g/L,mean cell volume(MCV)79 fl,white blood cell count(WBC)1.9×10^(9)/L,absolute neutrophil count(ANC)3.2×10^(9)/L,and platelet count 260×10^(9)/*** CBC a few days later showed worsening of the leukopenia and *** hospital admission,the patient had a history of fever and lethargy for 11 *** history revealed that his father is a farm *** physical examination showed massive hepatosplenomegaly.

关键词： patient anemia editor

Volvulus of Small Bowel Caused by GISTs: Case Report and Literature Review

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Case Reports in Clinical Medicine 2022年第5期11卷 200-205页

作者： Muhaned Alhassan Ayman Barghash hatem Al-Saadi Department of General Surgery Sohar Hospital Sohar Oman Sohar Hospital Sohar Oman

Introduction: Gastrointestinal stromal tumors (GISTs) originating from the interstitial cells of Cajal and GISTs are the most frequent mesenchymal tumors in the gastrointestinal tract (20% to 30% occur in the small intestine). Most small-intestinal neoplasms are asymptomatic. The most common mode of presentation is partial small bowel obstruction, with associated symptoms of colicky abdominal pain, abdominal distention, nausea, and vomiting. Obstruction can be caused by luminal narrowing by the tumor itself or intussusception. Case Presentation: We presented an 85-year-old lady presented with acute intestinal obstruction and CT abdomen with contrast revealed, a large well defined solid mass lesion, enhanced in the arterial phase and inseparable from the jejunal loops and it measures 09 × 08 × 07 cm, likely GISTs with secondary volvulus of the small bowel. Emergency laparotomy with complete resection of the tumor and end-to-end anastomosis of jejunum was done. Discussion: Small-intestinal GISTs should be treated with segmental intestinal resection. If the diagnosis is known prior to resection, wide lymphadenectomy can be avoided as GISTs are rarely associated with lymph node metastases. GISTs are resistant to conventional chemotherapy agents. Imatinib (Gleevec) is a tyrosine kinase inhibitor with potent activity against the tyrosine kinase KIT and is used in those with metastatic disease and as an adjuvant chemotherapeutic agent.

关键词： GISTs Small Intestine MRI CT Scan Imatinib Tyrosine Kinase Inhibitor