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Journal of Physical Science and Application 2014年第5期4卷 310-316页

作者： Ahmed Abdelghafar Galahom ibrahim Ismail bashter Moustafa Aziz Higher Technological Institute l Oth of Ramadan City Sharkia Egypt Zagazig University Faculty of Science Physics Department Zagazig City Sharkia Egypt Nuclear Regulatory Commission and Radiological Nasr City Cairo Egypt

In the last few years, interest in burnup calculations using Monte Carlo methods has increased. Previous burnup codes have used diffusion theory for the neutronic portion of the codes. Diffusion theory works well for most reactors. However, diffusion theory does not produce accurate results in burnup problems that include strong absorbers or large voids. MCNPX code based on Mont Carlo Method, is used to design a three dimensional model for a BWR fuel assembly in a typical operating temperature and pressure conditions. A test case was compared with a benchmark problem and good agreement was found. The model is used to calculate the distribution of pin by pin power and flux inside the assembly. The effect of axial variation of water （coolant） density, and of control rods motion on the neutron flux and power distribution is analyzed. The effect of addition of Gd2O3 to natural uranium （0.711%） on both the thermal neutron flux and normalized power are analyzed. The concentration of U^235, U^238, Pu^239, and its isotopes is also calculated at burn-up 50 GWD/T.

关键词： MCNPX Code boiling water reactor thermal neutron flux normalized power multiplication factor.

The Effect of Absorbed Dose to Organs at Risk Following Craniospinal Irradiation Using Different Radiotherapy Techniques

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2020年第2期9卷 73-85页

作者： Hadeer A. Shahin Ehab M. Attalla H. S. Abou-Elenien Hussein Elsayed ibrahim bashter Marwa A. Suliman Physics Department Faculty of Science Zagazig University Zagazig Egypt Radiotherapy Department National Cancer Institute Cairo Egypt Radiotherapy Department Children’s Cancer Hospital Cairo Egypt Clinical Oncology & Nuclear Medicine Department Faculty of Medicine Suez Canal University Ismailia Egypt

Introduction: In medulloblastoma patients craniospinal irradiation is an important element the treatment. Our study aimed to evaluate the effect of absorbed dose to organs at risk using the hybrid intensity-modulated radiation therapy (IMRT) versus three-dimensional conformal radiotherapy (3DCRT) for craniospinal irradiation (CSI) in average risk medulloblastoma patients. Materials and Methods: In this study, thirteen medulloblastoma patients were included. The prescribed total dose to the planning target volume (PTV) was 23, 40 Gy in 13 fractions. Two radiotherapy techniques, three dimensional conformal radiotherapy (3DCRT) and hybrid intensity modulated radiotherapy (IMRT) were used to treat these patients. The coverage of the Target was evaluated using the D mean, D95%, D2%, D98% and V95%. Other parameters were also compared such as Integral dose (ID), Homogeneity index (HI) and doses to the organs at risk (OARs). Results: There was no significant difference in the mean dose received by the PTV-Brain or the dose received by 95% and 98% of PTV volume using the two techniques. For PTV-Spine, the percentage volume receiving 95% of the total dose increased significantly in the hybrid IMRT technique compared to the conformal technique. So, hybrid IMRT plan achieved the best coverage for PTV spine. Lower dose for OAR was delivered by 3DCRT, except the heart and thyroid, hybrid IMRT achieved better sparing. All plans resulted in the same dose homogeneity index (DHI) for PTV-Brain. For PTV-Spine, hybrid IMRT technique achieved better dose homogeneity compared to 3DCRT technique (1.09 vs. 1.12;p > 0.05). Conclusions: hybrid IMRT technique can be realized on conformal technique because it achieved better dose coverage for the (PTV) and organ at risk (OAR). 3DCRT reduced mean dose to most OARS, except the heart and thyroid. Therefore, the hybrid IMRT technique may be a CSI treatment alternative to 3DCRT.

关键词： Craniospinal Irradiation Three-Dimensional Conformal Radiotherapy Intensity-Modulated Radiation Therapy Medulloblastoma Organs at Risk Homogeneity Index

Classifying rockburst with confidence:A novel conformal prediction approach

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International Journal of Mining Science and Technology 2024年第1期34卷 51-64页

作者： Bemah ibrahim Isaac Ahenkorah University of South Australia UniSA STEMSA 5000Australia

The scientific community recognizes the seriousness of rockbursts and the need for effective mitigation *** literature reports various successful applications of machine learning(ML)models for rockburst assessment;however,a significant question remains unanswered:How reliable are these models,and at what confidence level are classifications made?Typically,ML models output single rockburst grade even in the face of intricate and out-of-distribution samples,without any associated confidence *** the susceptibility of ML models to errors,it becomes imperative to quantify their uncertainty to prevent consequential *** address this issue,we propose a conformal prediction(CP)framework built on traditional ML models(extreme gradient boosting and random forest)to generate valid classifications of rockburst while producing a measure of confidence for its *** proposed framework guarantees marginal coverage and,in most cases,conditional coverage on the test *** CP was evaluated on a rockburst case in the Sanshandao Gold Mine in China,where it achieved high coverage and efficiency at applicable confidence ***,the CP identified several“confident”classifications from the traditional ML model as unreliable,necessitating expert verification for informed *** proposed framework improves the reliability and accuracy of rockburst assessments,with the potential to bolster user confidence.

关键词： Rockburst Machine learning Uncertainty quantification Conformal prediction

New insights into astrocyte diversity from the lens of transcriptional regulation and their implications for neurodegenerative disease treatments

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Neural Regeneration Research 2024年第11期19卷 2335-2336页

作者： ibrahim Olabayode Saliu Guoyan Zhao Department of Genetics Washington University School of MedicineSt.LouisMOUSA Department of Neurology Department of Pathology and ImmunologyWashington University School of MedicineSt.LouisMOUSA

Astrocytes are a major glial cell type in the central nervous system,and they provide trophic and metabolic support to *** addition to these roles,they play crucial roles in modulating synaptic functions,development,and pruning(Brandebura et al.,2023).Astrocytes become reactive(activated)by undergoing morphological,molecular,and functional alterations in response to neuropathology such as in injuries and neurodegenerative diseases(NDs)(Escartin et al.,2021).

关键词： degenerative injuries

Enteric neuropathy in diabetes:Implications for gastrointestinal function

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World Journal of Gastroenterology 2024年第22期30卷 2852-2865页

作者： Mona Mohamed ibrahim Abdalla Department of Human Biology School of MedicineInternational Medical UniversityBukit Jalil 57000Kuala LumpurMalaysia

Diabetes,commonly known for its metabolic effects,also critically affects the enteric nervous system(ENS),which is essential in regulating gastrointestinal(GI)motility,secretion,and *** development of diabetes-induced enteric neuropathy can lead to various GI dysfunctions,such as gastroparesis and irregular bowel habits,primarily due to disruptions in the function of neuronal and glial cells within the ENS,as well as oxidative stress and *** editorial explores the pathophysiological mechanisms underlying the development of enteric neuropathy in diabetic ***,it discusses the latest advances in diagnostic approaches,emphasizing the need for early detection and intervention to mitigate GI complications in diabetic *** editorial also reviews current and emerging therapeutic strategies,focusing on pharmacological treatments,dietary management,and potential neuromodulatory ***,this editorial highlights the necessity of a multidisciplinary approach in managing enteric neuropathy in diabetes,aiming to enhance patient quality of life and address a frequently overlooked complication of this widespread disease.

关键词： Diabetic neuropathy Gastrointestinal Insulin resistance Diabetes Enteric nervous system Enteric neuropathy

Numerical modelling and simulation analysis of wind blades: a critical review

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CLEAN ENERGY 2024年第1期8卷 261-279页

作者： Alrowwad, ibrahim Wang, Xiaojia Zhou, Ningling Southeast Univ Sch Energy & Environm Key Lab Energy Thermal Convers & Control Minist Educ Nanjing 210096 Peoples R China

Wind energy has emerged as a promising renewable energy source and wind turbine technology has developed rapidly in recent years. Improved wind turbine performance depends heavily on the design and optimization of wind blades. This work offers a critical evaluation of the state of the art in the field of numerical modelling and simulation analysis, which have become crucial for the design and optimization of wind blades. The evaluation of the literature includes considerable research on the application of numerical methods for the structural and aerodynamic performance of wind blades under various operating situations, as well as for analysis and optimization of wind blades. The article illustrates how numerical techniques can be used to analyse wind blade performance and maximize design efficiency. The study of blade performance under various wind conditions has also been made possible through the use of simulation analysis, thus enhancing the efficiency and dependability of wind turbines. Improvements in wind turbine efficiency and dependability, and ultimately the move towards a more sustainable energy future, will be greatly helpful for the development of numerical modelling and simulation techniques. This review offers a critical evaluation of the state of the art in the field of numerical modelling and simulation analysis, which have become crucial for the design and optimization of wind blades. Graphical Abstract

关键词： wind blades simulations optimization numerical analysis mathematical modelling performance OF-THE-ART TURBINE BLADE AERODYNAMIC PERFORMANCE STRUCTURAL-ANALYSIS FATIGUE ANALYSIS COMPUTATIONAL ANALYSIS BEAM MODEL COMPOSITE FAILURE DESIGN

Analysis of Neutronic Characteristics of Uranium Zirconium Hydride Fuel in Advanced Boiling Water Reactor

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材料科学与工程（中英文A版） 2013年第6期3卷 437-442页

作者： Ahmed Abdelghafar Galahom ibrahim Ismail bashter Moustafa Aziz Higher Technological Institute l Oth of Ramadan city Sharkia Egypt Physics Department Faculty of Science Zagazig University Zagazig City Sharkia Egypt Nuclear Regulatory Commission and Radiological Regulatory Authority Nasr City Egypt

This paper presents a design of an advanced boiling water reactor (ABWR) equilibrium bundle using UZrH1.6 as a fuel. Monte Carlo N-Particle Transport (MCNPX) code extended has been used for design advanced boiling water reactor model. MCNPX code based on Mont Carlo Method is used to design a three dimensional model for a BWR fuel assembly in a typical operating temperature and pressure conditions. A test case was compared with a benchmark problem, and good agreement was found. This model is used to calculate the distribution of pin by pin power and flux inside the assembly, calculate the axial thermal neutron flux and the axial normalized power across the fuel rod at different insertion of control rod, and to study the effect of increasing the fuel enrichment on the axial thermal neutron flux and the axial normalized power.

关键词：先进沸水堆燃料组件中子通量氢化锆蒙特卡罗法特性三维模型 ABWR

Relational Turkish Text Classification Using Distant Supervised Entities and Relations

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Computers, Materials & Continua 2024年第5期79卷 2209-2228页

作者： Halil ibrahim Okur Kadir Tohma Ahmet Sertbas Department of Computer Engineering Faculty of Engineering and Natural SciencesIskenderun Technical UniversityHatay31200Turkey Department of Computer Engineering Faculty of EngineeringIstanbul University-CerrahpasaIstanbul34310Turkey

Text classification,by automatically categorizing texts,is one of the foundational elements of natural language processing *** study investigates how text classification performance can be improved through the integration of entity-relation information obtained from the Wikidata(Wikipedia database)database and BERTbased pre-trained Named Entity Recognition(NER)*** on a significant challenge in the field of natural language processing(NLP),the research evaluates the potential of using entity and relational information to extract deeper meaning from *** adopted methodology encompasses a comprehensive approach that includes text preprocessing,entity detection,and the integration of relational *** conducted on text datasets in both Turkish and English assess the performance of various classification algorithms,such as Support Vector Machine,Logistic Regression,Deep Neural Network,and Convolutional Neural *** results indicate that the integration of entity-relation information can significantly enhance algorithmperformance in text classification tasks and offer new perspectives for information extraction and semantic analysis in NLP *** of this work include the utilization of distant supervised entity-relation information in Turkish text classification,the development of a Turkish relational text classification approach,and the creation of a relational *** demonstrating potential performance improvements through the integration of distant supervised entity-relation information into Turkish text classification,this research aims to support the effectiveness of text-based artificial intelligence(AI)***,it makes significant contributions to the development ofmultilingual text classification systems by adding deeper meaning to text content,thereby providing a valuable addition to current NLP studies and setting an important reference point for future research.

关键词： Text classification relation extraction NER distant supervision deep learning machine learning

(Sm/Eu/Tm)^(3+) doped tantalum semiconductor system for photovoltaic and electrochemical functionality amplification

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Journal of Rare Earths 2024年第8期42卷 1586-1594,I0007页

作者： Shaan Bibi Jaffri Khuram Shahzad Ahmad Isaac Abrahams ibrahim A.A Materials and Environmental Chemistry Lab Lab-E21Department of Environmental SciencesFatima Jinnah Women UniversityRawalpindiPakistan School of Physical and Chemical Sciences Queen Mary University of LondonLondonUnited Kingdom Department of Botany and Microbiology College of ScienceKing Saud UniversityP.O.Box 2455Riyadh11451Saudi Arabia

This work reports the synthesis,characterization,and energy focused applications of the novel lanthanides co-doped tantalum pentoxide hetero-system(Sm^(3+)-Eu^(3+)-Tm^(3+):Ta_(2)O_(5)).Ln^(3+)-doped Ta_(2)O_(5) express excellent opto-electronic features reflected by the narrow band gap energy of 3.87 *** vibrations confirm the presence of Ta-O-Ta and Ta-O *** synthesized system possesses orthorhombic geometry with 59.46 nm particle *** the smoother and compact morphology,the synthesized material succeeds in augmenting the performance of different systems aimed at energy *** ambient perovskite solar cell device fabricated with the Ln^(3+)-doped Ta_(2)O_(5) as an electron transport layer excels in achieving an efficiency and fill factor of 14.17% and 76% under artificial *** device was marked by the negligible hysteresis behavior showing profound photovoltaic *** electrochemical activity of the Ln^(3+)-doped Ta_(2)O_(5) decorated electrode was evaluated for electrical charge storage potential with pseudocapacitive behavior,With the highest specific capacitance of 355.39 F/g and quicker ionic diffusion rate,the designed electrode excels conventionally used ***-catalysis of water with Ln^(3+)-doped Ta_(2)O_(5) material indicates its capacity for H_(2) production with the lowest overpotential and Tafel slope values of 148 and 121.2 mV/dec,while the O_(2) generation is comparatively *** the stable electrochemical output,this rare earth modified material has the potential to replace conventionally used environmentally perilous and costly materials.

关键词： Lanthanide doping Rare earth materials Perovskite solar cells Supercapacitors Water splitting

Insulin resistance as the molecular link between diabetes and Alzheimer's disease

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World Journal of Diabetes 2024年第7期15卷 1430-1447页

作者： Mona Mohamed ibrahim Abdalla Department of Human Biology School of MedicineInternational Medical UniversityBukit Jalil 57000Kuala LumpurMalaysia

Diabetes mellitus(DM)and Alzheimer's disease(AD)are two major health concerns that have seen a rising prevalence *** studies have indicated a possible link between DM and an increased risk of developing ***,while primarily known for its role in regulating blood sugar,also plays a vital role in protecting brain *** resistance(IR),especially prevalent in type 2 diabetes,is believed to play a significant role in AD's *** insulin signalling becomes dysfunctional,it can negatively affect various brain functions,making individuals more susceptible to AD's defining features,such as the buildup of beta-amyloid plaques and tau protein *** research suggests that addressing insulin-related issues might help reduce or even reverse the brain changes linked to *** review aims to explore the relationship between DM and AD,with a focus on the role of *** also explores the molecular mechanisms by which IR might lead to brain changes and assesses current treatments that target *** IR's role in the connection between DM and AD offers new possibilities for treatments and highlights the importance of continued research in this interdisciplinary field.

关键词： Alzheimer's disease Insulin resistance Obesity Dementia Diabetes Metabolic syndrome