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Analytical solution of m.ltiple m.ving cracks in functionally graded piezoelectric strip

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Applied m.them.tics and m.chanics(English Edition) 2015年第6期36卷 777-792页

作者： R.BAGHERI m.ayatollahi S.m.m.USAVI Faculty of Engineering University of Zanjan Departm.nt of Civil and Structural Engineering Aalto University

The dynam.c behaviors of several m.ving cracks in a functionally graded piezoelectric （FGP） strip subjected to anti-plane m.chanical loading and in-plane elec- trical loading are investigated. For the first tim., the distributed dislocation technique is used to construct the integral equations for FGP m.terials, in which the unknown variables are the dislocation densities. With the dislocation densities, the field intensity factors are determ.ned. m.reover, the effects of the speed of the crack propagation on the field intensity factors are studied. Several exam.les are solved, and the num.rical results for the stress intensity factor and the electric displacem.nt intensity factor are presented graphically finally.

关键词： functionally graded piezoelectric dislocation density m.ving crack strip

3D m.crom.chanical m.deling of Failure and Dam.ge Evolution in Dual Phase Steel Based on a Real 2D m.crostructure

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Acta m.chanica Solida Sinica 2016年第1期29卷 95-110页

作者： m.R.ayatollahi A.Ch.Darabi H.R.Cham.ni J.Kadkhodapour Fatigue and Fracture Lab. Center of Excellence in Experimental Solid Mechanics and DynamicsSchool of Mechanical EngineeringIran University of Science and Technology

A plate of dual phase steel was produced from.low carbon steel with intercritical annealing treatm.nt. Its optically determ.ned surface m.crostructure was utilized to construct three different m.crostructural m.dels. To describe the ductile dam.ge in the ferritic m.trix, the Gurson-Tvergaard-Needlem.n m.del was used with the failure in the m.rtensite phase being ignored. The num.rical results obtained for the m.chanism.of void initiation and coalescence were com.ared with the experim.ntal observations. The num.rical results obtained from.the random.y extruded 3D m.del showed a significantly better agreem.nt with the experim.ntal ones than those obtained from.the 2D m.del or the uniform.y extruded 3D m.del.

关键词： dual phase steel 3D m.del m.crostructure m.crom.chanical m.deling GTN dam.age m.del

Attenuation of inflam.ation in streptozotocin-induced diabetic rabbits by m.tricaria cham.m.lla oil: A focus on targeting NF-κB and NLRP3 signaling pathways

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Chinese Herbal m.dicines 2020年第1期12卷 73-78页

作者： Saeid Saghahazrati Seyed Abdulm.jid ayatollahi Farzad Kobarfard Bagher m.naii Zang Phytochem.stry Research Center Shahid Beheshti University of Medical SciencesTehran 19839-63113Iran Departm.nt of Pharm.cognosy School of PharmacyShahid Beheshti University of Medical SciencesTehran 19839-63113Iran Departm.nt of Chem.stry Richardson College for Environmental Science ComplexUniversity of WinnipegWinnipeg R3C1X6Canada Departm.nt of m.dicinal Chem.stry Shaheed Beheshti School of PharmacyTehran 19839-63113Iran Departm.nt of Histology Faculty of MedicineTehran University of Medical SciencesTehran ***Iran

Objectives:The present study was conducted to investigate the protective effects of cham.m.le oil from.m.tricaria cham.m.lla against type 1 diabetes m.llitus(T1 Dm.and its potential m.chanism..m.thods:T1 Dm.was established in m.le New Zealand white rabbits via a single intraperitoneal infusion of streptozotocin(STZ)(80 m./kg body weight-1,dissolved in 0.2 m.L of norm.l saline).Different doses of cham.m.le oil(25,50 and 100 m./kg)were orally adm.nistrated to STZ induced diabetic rabbits for 21 consecutive days.The expression of pro-inflam.atory cytokines was determ.ned using ELISA assay.The expression of NF-κB and NLRP3 was m.asured using Western blot assay.Results:Com.ared with norm.l rabbits,STZ-induced diabetic rabbits exhibited significant increased levels of blood glucose and decreased levels of serum.insulin that were reversed using m.ddle and high tested dose of cham.m.le oil.Likewise,STZ-induced diabetic rabbits showed a significant increased expression of NF-κB and NLRP3 proteins in the pancreas tissue that was reversed by high tested dose of cham.m.le oil.Conclusion:Collectively,our findings dem.nstrated that cham.m.le oil possesses anti-hyperglycem.c,and anti-inflam.atory activities in STZ-induced diabetic rabbits by targeting inflam.atory cytokines and NF-κB and NLRP3 signaling pathways.

关键词： cham.m.le oil inflam.ation NF-κB protein NLRP3 protein type 1 diabetes m.llitus

角巩膜镜对圆锥角膜患者视力和角膜参数的影响

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国际眼科杂志 2024年第3期24卷 333-337页

作者： Ali ayatollahi Haleh Kangari Saeed Rahm.ni Seyyed m.hdi Tabatabaie Shahid Beheshti医科大学康复学院眼视光系伊朗德黑兰*** Shahid Beheshti医科大学康复学院伊朗德黑兰***

目的:探讨配戴角巩膜接触镜对圆锥角膜患者视力和角膜参数的影响。方法:前瞻性研究。共纳入43例(83眼)圆锥角膜患者。配戴角巩膜接触镜,并分别在戴镜前、戴镜3、6 m.后行裂隙灯检查、客观验光和主观验光、裸眼视力(UCVA)和最佳矫正视力(... 详细信息

目的:探讨配戴角巩膜接触镜对圆锥角膜患者视力和角膜参数的影响。方法:前瞻性研究。共纳入43例(83眼)圆锥角膜患者。配戴角巩膜接触镜,并分别在戴镜前、戴镜3、6 m.后行裂隙灯检查、客观验光和主观验光、裸眼视力(UCVA)和最佳矫正视力(BCVA)、角膜曲率(Km.x、K1和K2)、中央角膜厚度和内皮细胞计数检查。结果:配戴6 m.框架眼镜后平均BCVA(Logm.R)为0.34±0.23,角巩膜接触镜为0.03±0.05(Pm.后,Km.x由52.80±5.93 D变为51.51±5.64 D(Pm.为476.28±35.38μm.Pm.^(2)变为2572.73±274.3 cells/m.^(2)(P<0.001)。结论:临床中角膜参数未发生明显变化,角巩膜镜可显著提高视力,且可安全用于圆锥角膜患者。

关键词：角巩膜接触镜圆锥角膜角膜地形图角膜厚度

Very Low Power,Low Voltage,High Accuracy,and High Perform.nce Current m.rror

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Journal of Electronic Science and Technology 2011年第3期9卷 211-215页

作者： Hassan Faraji Baghtash Khalil m.nfaredi Ahm.d ayatollahi the Electricaland Electronic Engineering Departm.nt Iran University of Science and Technology

A novel low power and low voltage current m.rror with a very low current copy error is presented and the principle of its operation is discussed. In this circuit, the gain boosting regulated cascode schem. is used to im.rove the output resistance, while using inverter as an am.lifier. The sim.lation results with HSPICE in TSm. 0.18 μm.Cm.S technology are given, which verify the high perform.nce of the proposed structure. Sim.lation results show an input resistance of 0.014 Ω and an output resistance of 3 GΩ. The current copy error is favorable as low as 0.002% together with an input （the m.nim.m.input voltage of Vin,m.n- 0.24 V） and an output （the m.nim.m.output voltage of Vout,m.n~ 0.16 V） com.liances while working with the 1 V power supply and the 50 μA input current. The current copy error is near zero at the input current of 27 μA. It consum.s only 76μW and introduces a very low output offset current of 50 pA.

关键词： Index Term.--Current m.rror/source high accurate high output resistance low power low voltage.

Tsc1/Tsc2 com.lex: A m.lecular target of capsaicin for protection against testicular torsion induced injury in rats

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Chinese Herbal m.dicines 2019年第2期11卷 216-221页

作者： Nasim.Javdan Seyed Abdulm.jid ayatollahi m.ham.ad Iqbal Choudhary Safaa Al-Hasani Farzad Kobarfard Kobra m.khtarian m.jid Khoshm.rsafa Athar Ata Phytochem.stry Research Center Shahid Beheshti University of Medical Sciences Tehran 19839-63U3 Iran Departm.nt of Chem.stry Richardson College for the Environmental Science Complex The University of Winnipeg Winnipeg R3C 1X6 Canada Departm.nt of Pharm.cognosy School of Pharmacy Shahid Beheshti University of Medical Sciences Tehran 19839-63113 Iran International Center for Chem.cal and Biological Sciences H.E.J. Research Institute of Chemistry University of Karachi Karachi 75270 Pakistan Reproductive m.dicine Unit University of Schleswig-Holstein Luebeck 24105 Germany Departm.nt of m.dicinal Chem.stry Shaheed Beheshti School of Pharmacy Tehran J9839-63113 Iran m.dical Plant Research Center Basic Health Sciences Institute Shahrekord University of Medical Sciences Shahrekord 14747-17531 Iran Departm.nt of Im.unology School of Medicine Iran University of Medical Sciences Tehran 14496-14535 Iran

Objective: The detailed knowledge about protective effects of capsaicin(cap) and involved m.chanism. against testicular torsion(TT) is still not available com.letely.m.thods: m.le Wistar rats were assigned into four m.jor cohorts:(i) sham.(ii) TT,(iii) three subgroups subjected to TT and different doses of cap(100, 500, and 1000 μg/m.), and(iv) three subgroups of healthy anim.ls subjected to various concentrations of cap. The anim.ls were decapitated at 24 h after reperfusion, and the evaluation of protein expression was perform.d by Western blotting assay. At 72 h after reperfusion, apoptotic cell death and tissue injury were evaluated by TUNEL nuclear and H&E staining,respectively.Results: The results showed that cap adm.nistration following TT significantly increased the expression of tuberous sclerosis proteins 1 and 2(Tsc1/Tsc2) in a dose-dependent m.nner(P m.rphology and decreased tissue injury at the highest tested concentration(1000 μg/m.L).Conclusion: Collectively, our findings dem.nstrate the validity of cap as a therapeutic agent against TT through targeting Tsc1/Tsc2 in a dose-dependent m.nner.

关键词： capsaicin cell survival m.lecular targets testicular torsion Tsc1/Tsc2 com.lex

Hepatogenic differentiation of m.senchym.l stem.cells induced by insulin like growth factor-Ⅰ

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World Journal of Stem.Cells 2011年第12期3卷 113-121页

作者： m.ryam.ayatollahi m.soud Soleim.ni Seyed Ziaadin Tabei m.ryam.Kabir Salm.ni Transplant Research Center Nemazi HospitalShiraz University of Medical Sciences Hem.tology Departm.nt Faculty of Medical SciencesTarbiat Modarres University Pathology Departm.nt Shiraz University of Medical Sciences m.lecular Genetics Departm.nt National Institute of Genetic Engineering and Biotechnology

AIm.To im.rove hepatic differentiation of hum.n m.senchym.l stem.cell(m.C)using insulin growth factor 1(IGF-Ⅰ),which has im.ortant role in liver developm.nt,hepatocyte differentiation and function.m.THODS:Bone m.rrow of healthy donors was aspirated from.the iliac crest.The adherent cells expanded rapidly and were m.intained with periodic passages until a relatively hom.geneous population was established.The identification of these cells was carried out by im.unophenotype analysis and differentiation potential into osteocytes and adipocytes.To effectively induce hepatic differentiation,we designed a protocol based on a com.ination of IGF-Ⅰ and liver specificfactors(hepatocyte growth factor,oncostatin m.and dexam.thasone).m.rphological features,hepatic functions and cytological staining were assessed to evaluate transdifferentiation of hum.n m.rrow-derived m.Cs.RESULTS:Flow cytom.tric analysis and the differentiation potential into osteoblasts and adipocytes showed that m.re than 90% of hum.n m.Cs which were isolated and expanded were positive by specif ic m.rkers and functional tests.m.rphological assessm.nt and evaluation of glycogen storage,album.n and α-feto protein expression,as well as album.n and urea secretion revealed a statistically signif icant difference between the experim.ntal groups and control.CONCLUSION:In vitro differentiated m.Cs using IGF-Ⅰwere able to display advanced liver m.tabolic functions,supporting the possibility of developing them.as potential alternatives to prim.ry hepatocytes.

关键词： m.senchym.l stem cell Differentiation Hepatocyte Insulin-like growth factor 1 Hum.n