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Leukemia Inhibitory Factor Enhanced the Developmental and Implantation Compatibility of Mouse Embryos in Co-culture with Human Endometrial Epithelial Cells

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Reproductive and Developmental Medicine 2021年第4期5卷 199-205页

作者： Ali Hosseini Bahar Movaghar Showra Amani Abkenari Hassan Nazari mehrdad bakhtiyari Department of Anatomy Faculty of MedicineIran University of Medical SciencesTehranIran Cellular and Molecular Research Center Iran University of Medical SciencesTehranIran Department of Embryology Reproductive Biomedicine Research CenterRoyan Institute for Reproductive BiomedicineACECRTehranIran Department of Anatomy School of MedicineTehran University of Medical SciencesTehranIran Research Institute of Animal Embryo Technology Shahrekord UniversityShahrekordIran

Objective:Among the variousin vitro embryo culture systems,co-culture has demonstrated remarkable effects in pre-implantation embryo development owing to the production of embryo-nourishing ***,little is known about the secretion of these ***,in this study,the effect of leukemia inhibitory factor(LIF),one of the most important nourishing factors in the early development of mouse embryos,in human endometrial epithelial cells(hEECs)was ***:Two-cell stage embryos were collected from the oviducts of hyper-stimulated and mated mice and cultivated in a co-culture with an hEEC monolayer with or without *** quality and developmental and attachment potential rates of cultured embryos were evaluated by determining the levels of octamer-binding transcription factor 4(Oct4)and caudal type homeobox 2(Cdx2)***:LIF significantly increased the developmental rate(82.67%vs.61.04%,respectively)and attachment rate(64%vs.45.45%,respectively)of mouse embryos co-cultured with hEECs compared to those in untreated *** expression levels ofOct4 andCdx2 in blastocysts cultured in the presence of LIF were higher than those in blastocysts cultured without ***:Despite the secretion of LIF by hEECs during co-culture with embryos,the amount of this factor was insufficient,and its addition to the culture media could increase the developmental potential of embryos.

关键词： Caudal Type Homeobox 2 Embryo Development Leukemia Inhibitory Factor Octamer-Binding Transcription Factor 4

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Optimization of geometric parameters of reinforced sheets based on a cell-based smoothed discrete shear gap(CS-FEM-DSG3) method

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Journal of Central South University 2016年第8期23卷 2024-2035页

作者： mehrdad Sarafrazi Armen Adamian Mechanical Engineering Department School of Engineering Central Tehran BranchIslamic Azad University

Optimization of design features of reinforced sheet is investigated. Initially, equations governing composite structures are extracted based on Kirchhoff sheet model under bending using Hamilton's principal. Then, design parameters for the composite structure are extracted with simple supportive boundary conditions from proposed solution. Next, optimization is achieved by determining dimensions of a reinforced sheet specimen. Weight optimization of reinforced sheet structure has been obtained based on variations in thickness and number of longitudinal and transverse reinforcements. Buckling static characteristic is utilized in optimization process. To solve the extracted equations, semi-analytical method of CS-DSG3 has been applied. Results are presented in graphs that show variation of design parameters by changing the geometric parameters. ABAQUS software has been used for design verification. The results show that an increase in thickness of 3 mm skip value tends to be zero. Also, there is a change in the amount of deflection for sheets with a minimum thickness of 3 mm by increasing the number of longitudinal and transverse reinforcement. There is a good agreement between the numerical method of finite elements and the method X-FEM-DSG3.

关键词： optimization reinforced sheet design CS-FEM-DSG3 method

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Naturally fractured hydrocarbon reservoir simulation by elastic fracture modeling

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Petroleum Science 2017年第2期14卷 286-301页

作者： mehrdad Soleimani Faculty of Mining Petroleum and Geophysics Shahrood University of Technology Shahrood Iran

Accurate fluid flow simulation in geologically complex reservoirs is of particular importance in construction of reservoir *** approaches in naturally fractured reservoir simulation involve use of unstructured grids or a structured grid coupled with locally unstructured grids and discrete fracture *** methods suffer from drawbacks such as lack of flexibility and of ease of *** this study,I combined fracture modeling by elastic gridding which improves flexibility,especially in complex *** proposed model revises conventional modeling fractures by hard rigid planes that do not change through *** is a dubious assumption,especially in reservoirs with a high production rate in the *** proposed elastic fracture modeling considers changes in fracture properties,shape and aperture through the *** strategy is only reliable for naturally fractured reservoirs with high fracture permeability and less permeable matrix and parallel fractures with less *** of elastic fracture modeling results with conventional modeling showed that these assumptions will cause production pressure to enlarge fracture apertures and change fracture shapes,which consequently results in lower production compared with what was previously *** is concluded that an elastic gridded model could better simulate reservoir performance.

关键词： Reservoir performance Discrete fracture model Naturally fractured reservoir History matching Elastic gridding

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3D object retrieval based on histogram of local orientation using one-shot score support vector machine

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Frontiers of Computer Science 2015年第6期9卷 990-1005页

作者： Vahid mehrdad Hossein EBRAHIMNEZHAD Computer Vision Research Laboratory Electrical Engineering Faculty Sahand University of Technology Tabriz *** Iran

In this paper, a content based descriptor is pro- posed to retrieve 3D models, which employs histogram of local orientation （HLO） as a geometric property of the shape. The proposed 3D model descriptor scheme consists of three steps. In the first step, Poisson equation is utilized to define a 3D model signature. Next, the local orientation is calculated for each voxel of the model using Hessian matrix. As the final step, a histogram-based 3D model descriptor is extracted by accumulating the values of the local orientation in bins. Due to efficiency of Poisson equation in describing the models with various structures, the proposed descriptor is capable of discriminating these models accurately. Since, the inner vox- els have a dominant contribution in the formation of the de- scriptor, sufficient robustness against noise can be achieved. This is because the noise mostly influences the boundary vox- els. Furthermore, we improve the retrieval performance us- ing support vector machine based one-shot score （SVM-OSS） similarity measure, which is more efficient than the conven- tional methods to compute the distance of feature vectors. The rotation normalization is performed employing the prin- cipal component analysis. To demonstrate the applicability of HLO, we implement experimental evaluations of precision- recall curve on ESB, PSB and WM-SHREC databases of 3D models. Experimental results validate the effectiveness of the proposed descriptor compared to some current methods.

关键词： 3D model retrieval histogram of local orientation visual based shape descriptor poisson equation

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NEURAL NETWORK ANALYSIS APPLICATION TO PERMEABILITY DETERMINATION OF FIBERGLASS AND CARBON PREFORMS

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Chinese Journal of Polymer Science 2009年第2期27卷 221-229页

作者： Hossein Golestanian mehrdad Poursina Mechanical Engineering Group Faculty of EngineeringUniversity of ShahreKordShahreKord ***Iran

Preform permeability is an important process parameter in liquid injection molding of composite *** parameter is currently determined with time consuming and expensive experimental *** paper presents the application of a back-propagation neural network to predicting fiber bed permeability of three types of reinforcement mats. Resin flow experiments were performed to simulate the injection cycle of a resin transfer molding *** results of these experiments were used to prepare a training set for the back propagation neural network *** reinforcements consisted of plain-weave carbon,plain-weave fiberglass,and chopped fiberglass *** effects of reinforcement type, porosity and injection pressure on fiber bed permeability in the preform principal directions were ***,in the training of the neural network reinforcement type,these process parameters were used as the input *** bed permeability values were the specified output of the *** a result of the specified parameters,the program was able to estimate fiber bed permeability in the preform principal directions for any given processing *** results indicate that neural network may be used to predict preform permeability.

关键词： Artificial neural network Permeability Porosity Resin transfer molding.

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Teaching the User By Learning From the User:Personalizing Movement Control in Physical Human-robot Interaction

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IEEE/CAA Journal of Automatica Sinica 2017年第4期4卷 704-713页

作者： Ali Safavi mehrdad H.Zadeh Department of Electrical and Computer Engineering Kettering UniversityFlintMI 48504USA

This paper proposes a novel approach for physical human-robot interactions(pHRI), where a robot provides guidance forces to a user based on the user performance. This framework tunes the forces in regards to behavior of each user in coping with different tasks, where lower performance results in higher intervention from the robot. This personalized physical human-robot interaction(p2HRI) method incorporates adaptive modeling of the interaction between the human and the robot as well as learning from demonstration(LfD) techniques to adapt to the users' performance. This approach is based on model predictive control where the system optimizes the rendered forces by predicting the performance of the user. Moreover, continuous learning of the user behavior is added so that the models and personalized considerations are updated based on the change of user performance over time. Applying this framework to a field such as haptic guidance for skill improvement, allows a more personalized learning experience where the interaction between the robot as the intelligent tutor and the student as the user,is better adjusted based on the skill level of the individual and their gradual improvement. The results suggest that the precision of the model of the interaction is improved using this proposed method,and the addition of the considered personalized factors to a more adaptive strategy for rendering of guidance forces.

关键词： Haptic guidance learning from demonstration(LfD) personalized physical human-robot interaction(p2HRI) user performance

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DYNAMIC FRACTURE ANALYSIS OF AGED GLASSY POLYCARBONATE BY THE METHOD OF CAUSTICS

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Acta Mechanica Solida Sinica 2013年第5期26卷 448-457页

作者： Guiyun Gao Zheng Li mehrdad Negahban State Key Lab for Turbulence and Complex Systems and College of Engineering Peking University Department of Engineering Mechanics University of Nebraska-Lincoln

The purpose of this work is to investigate the dynamic fracture properties of glassy polycarbonate （PC） with different aging times. The optical method of caustics is adopted in which the shadow spot patterns are recorded by a high speed camera during the dynamic fracture process. Then, the dynamic crack propagation, the stress intensity factor （SIF） and the dynamic fracture toughness of aged PC are obtained through an analysis of the characteristic size of caustic pattern. Moreover, by combining with the investigation of the fracture surface and the energy release rate analysis, the influence of aging time on the dynamic fracture behavior is discussed. Results show that the dynamic fracture toughness and critical energy release rate of PC decreases with aging time for short aging times, whereas they have little change or even increase for longer aging times. Therefore, aging modifies the mechanical properties especially the dynamic fracture properties of PC nonlinearly, not linearly as generally thought of.

关键词： polycarbonate physical aging dynamic fracture stress intensity factor

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Laboratory large-scale pullout investigation of a new reinforcement ofcomposite geosynthetic strip

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第5期13卷 1147-1159页

作者： mehrdad Tajabadipour Seyed Hamid Lajevardi Department of Civil Engineering Sirjan University of TechnologySirjanIran Department of Civil Engineering Arak BranchIslamic Azad UniversityArakIran

In this paper,more than 70 large-scale pullout tests were performed to evaluate the performance of an innovative composite geosynthetic strip(CGS)reinforcement in sandy *** CGS reinforcement is composed of a geosynthetic strip(GS)and parts of a scrap truck tire as transverse *** experimental pullout results for the CGS reinforcement were compared with the suggested theoretical equations and ordinary reinforcements,including the GS,the steel strip(SS),and the steel strip with rib(SSR).The pullout test results show that adding three transverse members to the GS reinforcement(CGS3)with S/H?6.6(where S and H are the space and height of the transverse members,respectively)increases pullout resistance by more than 120%,170%,and 50%compared to the GS,the SS,and the SSR,*** result shows that the CGS3(CGS with three transverse members)reinforcement needs at least 55.5%,63%,and 33.3%smaller length compared to the GS,the SS,and the SSR,*** general,implementation of mechanically stabilized earth wall(MSEW)with the proposed strip may help geotechnical engineers prevent costly designs and solve the problem of MSEW implementation in cases where there are limitations of space.

关键词： Pullout resistance Composite geosynthetic strip(CGS) Soilegeosynthetic interface Scrap tires Large-scale pullout tests

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Analysis of reputation-based mining paradigm under dishonest mining attacks

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Blockchain(Research and Applications) 2022年第2期3卷 75-89页

作者： Pouya Pourtahmasbi mehrdad Nojoumian Florida Atlantic University Department of Electrical Engineering and Computer Science777 Glades RoadBoca RatonFL33431USA

Since the introduction of Bitcoin,numerous studies on Bitcoin mining attacks have been conducted,and as a result,many countermeasures to these attacks have been *** reputation-based mining paradigm is a comprehensive countermeasure solution to this problem with the goal of regulating the mining process and preventing mining *** is accomplished by incentivizing miners to avoid dishonest mining strategies using reward and punishment *** model was validated solely based on game theoretical analyses,and the real-world implications of this model are not known due to the lack of empirical *** shed light on this issue,we designed a simulated mining platform to examine the effectiveness of the reputation-based mining paradigm through data *** implemented block withholding attacks in our simulation and ran the following three scenarios:Reputation mode,non-reputation mode,and no attack *** comparing the results from these three scenarios,interestingly,we found that the reputation-based mining paradigm decreases the number of block withholding attacks,and as a result,the actual revenue of individual miners becomes closer to their theoretical expected *** addition,we observed that the confidence interval test can effectively detect block withholding attacks;however,the test also results in a small number of false positive *** the effectiveness of the reputation-based model relies on attack detection,further research is needed to investigate the effect of this model on other dishonest mining strategies.

关键词： Blockchain Cryptocurrency Mining attacks Block withholding attack Trust models Reputation systems

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ATM in breast and brain tumors:a comprehensive review

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Cancer Biology & Medicine 2018年第3期15卷 210-227页

作者： mehrdad Asghari Estiar Parvin Mehdipour Department of Medical Genetics School of Medicine Tehran University of Medical Sciences

The ATM gene is mutated in the syndrome,ataxia-telangiectasia(AT),which is characterized by predisposition to *** with AT have an elevated risk of breast and brain tumors Carrying mutations in ATM,patients with AT have an elevated risk of breast and brain *** increased frequency of ATM mutations has also been reported in patients with breast and brain tumors;however,the magnitude of this risk remains *** the exception of a few common mutations,the spectrum of ATM alterations is heterogeneous in diverse populations,and appears to be remarkably dependent on the ethnicity of *** review aims to provide an easily accessible summary of common variants in different populations which could be useful in ATM screening *** addition,we have summarized previous research on ATM,including its molecular *** attempt to demonstrate the significance of ATM in exploration of breast and brain tumors and its potential as a therapeutic target.

关键词： Breast cancer brain tumor DNA damage DNA repair

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