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A Distance Function for Computing on Finite Subsets of Euclidean Spaces

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Acta Mathematicae Applicatae Sinica 2018年第1期34卷 197-208页

作者： Hajar ghahremani-Gol Farzad Didehvar Asadollah Razavi Department of Mathematics Faculty of Science Shahed University Tehran *** Iran Department of Mathematics and Computer Science Amirkabir University of Technology 424 Hafez Av Tehran *** Iran Department Pure Mathematics Faculty of Mathematics and Computer Science Shahid Bahonar University of Kerman Kerman Iran

In practical purposes for some geometrical problems, specially the fields in common with computer science, we deal with information of some finite number of points. The problem often arises here is： “How are we able to define a plausible distance function on a finite three dimensional space？” In this paper, we define such a distance function in order to apply it to further purposes, e.g. in the field settings of transportation theory and geometry. More precisely, we present a new model for traveling salesman problem and vehicle routing problem for two dimensional manifolds in three dimensional Euclidean space, the second problem on which we focus on this line is, three dimensional triangulation.

关键词： geodesic least square method vehicle routing problem traveling salesman problem three dimensional triangulation

Detailed seismic risk analysis of electrical substation equipment using a reliability based approach

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Earthquake Engineering and Engineering Vibration 2023年第2期22卷 495-511页

作者： Amir ghahremani Baghmisheh Milad Khodaei Ali Zare Feiz Abadi Homayoon E.Estekanchi Department of Civil Engineering University of British ColumbiaVancouver V6T 2B8Canada Department of Civil Engineering University of TabrizTabriz 51666Iran Department of Civil Engineering Sharif University of TechnologyTehran 11155-9313Iran

This paper proposes a risk analysis framework for substation structures based on reliability *** though several risk assessment approaches have been developed for buildings,detailed risk analysis procedures for infrastructure components have been lacking in prior *** proposed framework is showcased by its application to a system of interconnected structures at a power substation in *** element models of structures are developed and validated in accordance with previous *** uncertainties in the material,mass,and geometric properties of structures are described by random variables that are input to the finite element *** artificial ground motion model is employed to comprehensively consider uncertainty in ground *** Carlo sampling is subsequently conducted on the library of probabilistic *** analysis resulted in the loss distribution in the life cycle of ***,the loss associated with six earthquake scenarios having specific magnitudes and return periods is *** application provides insight into the most vulnerable equipment in the considered ***,introduced risk measures can guide stakeholders to make risk-based decisions to optimize design or prioritize a retrofit of infrastructure components under conditions of uncertainty.

关键词： seismic risk reliability analysis infrastructure components loss estimation uncertainty

Overcoming seed dormancy of mooseer(Allium hirtifolium) through cold stratification,gibberellic acid,and acid scarification

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Journal of Forestry Research 2012年第4期23卷 707-710页

作者： Farshad Dashti Hojat ghahremani-Majd Mahmood Esna-Ashari Department of Horticultural Sciences Faculty of AgricultureBu-Ali Sina UniversityHamedan ***Iran

Mooseer （Allium hirtifolium Boiss.） is bulbous perennial herb widely used in pharmaceutical and food industry in Iran. We studied germination of mooseer seeds in two separate experiments. In the first experiment, we evaluated four treatments： sulfuric acid scarification, sandpaper scarification, cold stratification, and gibberellic acid （GA3） application. In the second experiment, we evaluated combinations of these treatments. All treatments in the first experiment had no effect on seed germination, suggesting that mooseer seeds have physical and physiological dormancy. In the second experiment, the highest germina- tion percentage （86.6%） was observed after five minutes scarification with sulfuric acid （75% v/v）, followed by 60 days of cold stratification. Duration of sulfuric acid scarification （5, 10, and 20 min） did not affect germination rates, but increasing duration of cold stratification （from 15 to 60 days）, increased germination from 28.3% to 86.6%. Our study showed that mooseer seeds have both physical and physiological dormancy.

关键词： physical dormancy physiological dormancy germination sulfuric acid sand paper Allium hirtifolium

Influence of welding parameters on fracture toughness and fatigue crack growth rate in friction stir welded nugget of 2024-T351 aluminum alloy joints

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Transactions of Nonferrous Metals Society of China 2016年第10期26卷 2567-2585页

作者： Danial ghahremani MOGHADAM Khalil FARHANGDOOST Department of Mechanical Engineering Faculty of EngineeringFerdowsi University of Mashhad

Friction stir welding （FSW） was performed on 2024-T351 aluminum alloy plates. Metallographic analysis, Vickers microhardness and XRD tests were conducted to determine the properties of the welded zone. FE simulation of the FSW process was implemented for the different welding conditions to extract the residual stress and stress intensity factor （SIF）. Fracture and fatigue behaviors of the welds which have the initial crack in the nugget zone and the crack orientation along the welding direction, were studied based on standard test methods. Fracture behavior of the welds was also evaluated by shearography method. The results showed that the tool rotational and traverse speeds affect the fracture toughness and fatigue crack growth rate. FSW provides 18%-49% reductions in maximum fracture load and fracture toughness. A slight diminution in fracture toughness of the joints was observed for lower traverse speed of the tool, and at higher traverse or rotational speeds, increasing the probability of defects may contribute to low fracture toughness. Fatigue crack propagation rate of all welds was slower than that of the base metal for low values of stress intensity factor range ΔK （ΔK〈13 MPa·m^1/2）, but is much faster for high values of ΔK.

关键词： aluminum alloy friction stir welding fracture toughness shearography fatigue crack propagation rate

Chest computed tomography findings of COVID-19 in children younger than 1 year: a systematic review

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World Journal of Pediatrics 2021年第3期17卷 234-241页

作者： Alireza Ghodsi Moniba Bijari Seyed Ali Alamdaran Amin Saberi Elnaz Mahmoudabadi Mohammad Reza Balali Sara ghahremani Student Research Committee Faculty of MedicineMashhad University of Medical SciencesMashhadIran Radiology Department Faculty of MedicineMashhad University of Medical SciencesMashhadIran Faculty of Medicine Mashhad University of Medical SciencesAzadi SqMashhadIran Pediatrician Hasheminezhad HospitalMashhadIran Department of Pediatrics Faculty of MedicineMashhad University of Medical SciencesMashhadIran

Background The aim of this systematic review is to evaluate the chest computed tomography(CT)findings in infants with confirmed COVID-19 infection by providing a comprehensive review of the existing *** sources A systematic search was conducted on PubMed and Embase from the onset of the COVID-19 outbreak to October 20,2020,for studies that discussed the chest CT findings in infants younger than 1 year with COVID-19 *** A total of 35 studies comprising 70 COVID-19(58.5% boys)confirmed infants were *** mean age of the included patients was 4.1 months with a range of 1 day to 12 *** CT scans showed bilateral abnormalities in 34 patients,and unilateral lung involvement in 25 ***-glass opacities(GGO)(71.43%)were found to be the most prevalent chest CT manifestation,followed by peribronchial thickening(60%),linear or band-shaped opacities(32.8%),consolidation(28.57%),nodule(18.57%),effusion(7.14%)and focal lucency(7.14%).Conclusions GGO and peribronchial thickening were the most prevalent findings in the infants’chest CT *** or band-shaped opacities,consolidation,and pulmonary nodules are more common in infants than in *** findings suggest that the disease is more likely to be presented as an atypical pneumonia(peribronchial thickening and linear or bandshaped opacities)in this age *** chest CT scan manifestations can be classified as typical COVID-19 infection(peripheral GGO),lobar pneumonia(consolidation)and opportunistic infections(pulmonary nodules).

关键词： Computerized tomography COVID-19 Infant SARS-CoV-2 Systematic review

Dual effects of 3,4-methylenedioxymethamphetamine (ecstasy) on survival and apoptosis of primary hippocampal neurons

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Neural Regeneration Research 2009年第12期4卷 1068-1072页

作者： Abolfazl Azami Parichehr Pasbakhsh Mohammad Akbari Mohammad Barbarestani Mohammadhosein ghahremani Mohammadali Shokrgozar Ali Mandegary Amir Kiani Gholamreza Hassanzadeh Department of Anatomy School of MedicineTehran University of Medical Sciences Department of Toxicology-Pharmacology Faculty of PharmacyTehran University of Medical Sciences National Cell Bank of Iran Pasteur Institute of Iran School of Pharmacy Kermanshah University of Medical Scences

BACKGROUND： 3, 4-methylenedioxymethamphetamine （MDMA, also known as ＂ecstasy＂） has been shown to exhibit neurotoxic effects on the hippocampus. However, exposure to sub-lethal insults of MDMA has been reported to result in neuroprotection. OBJECTIVE： To investigate the effects of MDMA on hippocampal neuronal viability, caspase-3 activity, and mRNA expression of the N-methyI-D-aspartate （NMDA） receptor 2B （NR2B） subunit. DESIGN, TIME AND SETTING： A cytological, in vitro experiment was performed at the Department of Anatomy, School of Medicine, and Department of Toxicology-Pharmacology, Faculty of Pharmacy Tehran University of Medical Sciences in 2008. MATERIALS： MDMA was extracted from ecstasy tablets, which were kindly supplied by the Pharmacology-Toxicology Department, Faculty of Pharmacy, Tehran University of Medical Sciences, Iran. METHODS： Hippocampal neurons were isolated from Wistar rats at gestational day 18. Following primary culture, hippocampal neuronal viability was detected by MTT assay. Varying concentrations of MDMA （100-5 000 μmol/L） were used to determine lethal concentration 50 （LC50）, which was around 1 500 μmol/L. Five concentrations of MDMA below 1 500 μmol/L （100, 200, 400, 800, and 1 050 μmol/L） were used for the remaining experiments. After 24 hours of MDMA treatment, NR2B mRNA expression was detected by RT-PCR, and caspase-3 relative activity was determined by colorimetric assay. MAIN OUTCOME MEASURES： Hippocampal neuronal viability, caspase-3 activity, and NR2B mRNA expression. RESULTS： MDMA-induced neurotoxicity in hippocampal neuronal cultures was dose-dependent. In high concentrations （1 000-5 000μmol/L） of MDMA, neuronal viability was decreased. However, with a 500 μmol/L dose of MDMA, neuronal viability was significantly increased （P 〈 0.01）. Low concentrations of MDMA （200 and 400μmol/L） significantly decreased caspase-3 activity （P 〈 0.01）, whereas high concentrations of MDMA significantly increased caspase-3 activity （P 〈 0.01）. NR2B

关键词： 3, 4-methylenedioxymethamphetamine ecstasy apoptosis N-methyI-D-aspartate neuronal culture

Interpretation of thermal dependence of magnetic aftereffect for magnetic nanocomposite with slow decay rates

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International Journal of Smart and Nano Materials 2013年第2期4卷 91-101页

作者： Shuo Gu Yi Jin Gary R.Kahler Ming Zhang Peijie Chen Mohammadreza ghahremani Edward Della Torre Lawrence H.Bennett Department of Electrical and Computer Engineering The George Washington UniversityWashington DC 20052 USA Department of Chemistry The George Washington UniversityWashington DC 20052USA

A new experimental characterization is presented of time-,field-,and temperature-dependent dynamic effects in magnetization of a nanocomposite which displays slow *** and temperature variations of irreversible susceptibility,χirr,decay coefficient,S,fluctuation field,hf,and activation volume,V,have been calculated for the nanocomposite sample(Co_(80)Ni_(20))using a recently developed modified Preisach–Arrhenius(MPA)*** sample is composed of non-interacting nanoparticles having negligible reversible ***-Arrhenius behavior is observed in both the maximum decay coefficient,Smax,and the fluctuation field,hf,as a function of temperature *** peak of both temperature curves are identical and occur at a critical temperature Tk of∼50 K,which agrees with our experimental *** on the effect of a temperature-dependent chemical potential on energy barrier,hf is studied for T

关键词： magnetic aftereffect fluctuation field numerical modeling Co_(80)Ni_(20)nanocomposite

博舍酒店——访Make Architects Katy ghahremani,太古酒店Brian Williams

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建筑技艺 2015年第7期21卷 88-95页

作者：吴春花 Katy ghahremani Brian Williams <建筑技艺>杂志社(AT) Make Architects 太古酒店

AT：博舍是太古酒店集团继香港的奕居和北京的瑜舍后,第三个House品牌酒店。作为一个城市型酒店,其希望自身区别于其他品牌酒店的特点是什么？博舍又有哪些特点？Brian Williams：The House Collective酒店系列由多家设计独特的当代豪... 详细信息

AT：博舍是太古酒店集团继香港的奕居和北京的瑜舍后,第三个House品牌酒店。作为一个城市型酒店,其希望自身区别于其他品牌酒店的特点是什么？博舍又有哪些特点？Brian Williams：The House Collective酒店系列由多家设计独特的当代豪华酒店组成,为宾客提供高度个性化的服务。House系列的几家酒店各具特色,酒店设计别具匠心,内部装饰营造出温暖的氛围。每间酒店都设有极致舒适的客房和特色餐厅,致力于让宾客入住后产生宾至如归的亲切感。

关键词： Brian Williams 高度个性化内部装饰城市型 hotel heritage Temple 外部设计庭院空间 shadow

Design,synthesis and pharmacological evaluation of 4-[2-alkylthio-5(4)-(4-substitutedphenyl)imidazole-4(5)yl]benzenesulfonamides as selective COX-2 inhibitors

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Acta Pharmacologica Sinica 2007年第8期28卷 1254-1260页

作者： Mona SALIMI Mohammad Hossein ghahremani Nima NADERI Mohsen AMINI Elika SALIMI Massoud AMANLOU Khosrou ABDI Raha SALEHI Abbas SHAFIEE Research and Development Center Pasteur Institute of IranKasasIran Department of Pharmacology and Toxicology Faculty of Pharmacy and Pharmaceutical Sciences Research CenterTehran University of Medical SciencesTehranIran Neuroscience Research Center Shahid Beheshti University of Medical SciencesTehranIran Department of Medicinal Chemistry Faculty of Pharmacy and Pharmaceutical Sciences Research CenterTehran University of Medical SciencesTehranIran Department of Pharmacology Faculty of PharmacyMazanderan University of Medical SciencesSariIran

Aim:To design and synthesize a series of benzenesulfonamide derivatives,4-[2-alkylthio-5（4）-（4-substitutedphenyl）imidazole-4（5）-yl]benzenesulfonamides（4a-4j）,which are intended to act as cyclooxygenase-2（COX-2）inhibitors with goodCOX-2 inhibitor activity,and which will exert anti-inflammatory activities in ***:Benzenesulfonamide derivatives were designed and synthesized throughmulti-step chemical *** the synthesized compounds were evaluated inan in vitro *** active compound 4a-af was selected for further evaluationin a carrageenan-induced rat paw edema ***:Docking studies showedthat compound 4 bind into the primary binding site of COX-2 with the sulfonamideSO2NH2moiety interacting with the secondary pocket amino acid *** thein vitro assay,compound 4 inhibited COX-2 with an inhibition concentration IC50value of 1.23-8 nmol/L,compared to celecoxib with IC50 value of 1.5 nmol/***-pound 4b and 4c had good potency and selectivity in comparison to the *** the in vivo model,compound 4a-4f exhibited a moderate potency to inhibit 50%carrageenan-induced paw edema with value of 1.58-4.3 mg/*** the latterexperiment,compound 4c was the most active ***:The anti-inflammatory effects obtained for compound 4a-4j could be due to the presenceof fluorine or hydrogen substituents in the para position of the phenyl ring ofthese compounds.

关键词： cyclooxygenase-2 inhibitor imidazole alkylthio celecoxib