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Recycled glass replacement as fine aggregate in self-compacting concrete

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Frontiers of Structural and Civil Engineering 2013年第4期7卷 419-428页

作者： Yasser SHARIFI Mahmoud HOUSHIAR behnam AGHEBATI Department of Civil Engineering Vali-e-Asr University of RafsanjanRafsanjanIran

With increasing environmental pressure to reduce solid waste and to recycle as much as possible,the concrete industry has adopted a number of methods to achieve this goal by replacement of waste glass with concrete composition *** to differences in mixture design,placement and consolidation techniques,the strength and durability of Self Compacting Concrete(SCC)may be different than those of conventional ***,replacement of waste glass with fine aggregate in SCC should deeply be investigated compared to conventional *** aim of the present study is to investigate the effect of glass replacement with fine aggregate on the SCC *** present study,fine aggregate has been replaced with waste glass in six different weight ratios ranging from 0%to 50%.Fresh results indicate that the flow-ability characteristics have been increased as the waste glass incorporated to paste ***,compressive,flexural and splitting strengths of concrete containing waste glass have been shown to decrease when the content of waste glass is *** strength reduction of concrete in different glass replacement ratios is not remarkable,thus it can be produced SCC with waste glass as fine aggregate in a standard manner.

关键词： Self Compacting Concrete(SCC) recycle glass fine aggregate fresh and hardened properties

Osteoporosis:A Silent Disease with Complex Genetic Contribution

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Journal of Genetics and Genomics 2016年第2期43卷 49-61页

作者： Maryam Marl Golchin Laleh Heidari Seyyed Mohammad Hossein Ghaderian Haleh akhavan-Niaki Department of Genetics Faculty of MedicineBabol University of Medical SciencesBabol ***lran Department of Medical Genetics Faculty of MedicineShahid Beheshti University of Medical Sciences&Health ServicesTehran ***lran

Osteoporosis is the most common multifactorial metabolic bone disorder worldwide with a strong genetic component. In this review, the evidence for a genetic contribution to osteoporosis and related phenotypes is summarized alongside with methods used to identify osteoporosis susceptibility genes. The key biological pathways involved in the skeleton and bone development are discussed with a particular focus on master genes clustered in these pathways and their mode of action. Furthermore, the most studied single nucleotide polymorphisms （SNPs） analyzed for their importance as genetic markers of the disease are presented. New data generated by next- generation sequencing in conjunction with extensive meta-analyses should contribute to a better understanding of the genetic basis of osteoporosis and related phenotype variability. These data could be ultimately used for identifying at-risk patients for disease prevention by both controlling environmental factors and providing possible therapeutic targets.

关键词： Osteoporosis Bone mineral density Regulatory pathways Single nucleotide polymorphisms

Effects of Hydro-alcoholic Extract of Launaea acanthodes on Serum Gonadotropin and Testosterone Levels and the Structure of Seminiferous Tubules in Hyperglycemic Rats

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Chinese Journal of Integrative Medicine 2016年第3期22卷 207-213页

作者： Ameneh Mohammadi Morteza behnam-Rassouli Zeinab Momeni Naser Mahdavi-Shahri Department of Biology Faculty of ScienceFredowsi University of Mashhad

Objective： To investigate the effects of hydro-alcoholic extract of Launaea acanthodes, a blood glucose lowering plant in folk medicine of Iran, on the structure of seminiferous tubules and serum gonadotropin and testosterone levels in hyperglycemic rats. Methods： Twenty-four Wistar rats were randomly allocated into 4 groups （n=6）： control, streptozotocin （STZ）, STZ ＋ insulin [STZ ＋ Ins, 5 IU/（kg·day）], and STZ ＋ Launaea acanthodes extract [STZ ＋ Ext, 150 mg/（kg·day）]. Blood samples were collected at the 2nd and 4th weeks for detection of testosterone, follicle stimulating hormone （FSH） and luteinizing hormone （LH） with enzyme-linked immuno sorbent assay （ELISA）, and the dght testes of rats were removed at the 7th week for the evaluation of diameter and wall thickness of seminiferous tubules and number of Leydig cells using unbiased stereological techniques. Results： in comparison with the control group, at the 2nd week FSH （0.45 vs 0.03, 0.02, 0.02 lUlL in STZ, STZ ＋ Ins and STZ ＋ Ext groups, respectively） and LH （1.02 vs 0.37, 0.2, 0.29 IU/L） showed significant decreases （all P〈0.05） and testosterone （4.2 vs 8.37, 7.78, 11.8 ng/mL） showed a remarkable increase （all P〈0.05）. The levels of these hormones became closer in the STZ ＋ Ext and the STZ ＋ Ins groups to the control at the 4th week. A significant decrease in diameter and wall thickness of seminiferous tubules and number of Leydig cells were observed in the STZ group as compared with the control （P〈0.01）. Conclusions： Administration of Launaea extract demonstrated a beneficial impact on the protection of testis from pathogenic and degenerative effects of hyperglycemia which may be partly due to its potential antioxidative effects.

关键词： hyperglycemia Launaea acanthodes testis gonadotropins testosterone rat

Graph-theoretic defense mechanisms against false data injection attacks in smart grids

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Journal of Modern Power Systems and Clean Energy 2018年第5期6卷 860-871页

作者： Mohammad Hasan ANSARI Vahid Tabataba VAKILI behnam BAHRAK Parmiss TAVASSOLI Electrical Engineering Department Iran University of Science and Technology School of Electrical and Computer Engineering College of Engineering University of Tehran

This paper addresses false data injection, which is one of the most significant security challenges in smart grids. Having an accurately estimated state is of great importance for maintaining a stable running condition of smart grids. To preserve the accuracy of the estimated state, bad data detection(BDD) mechanisms are utilized to remove erroneous measurements due to meter failures or outside attacks. In this paper we use a graph-theoretic formulation for false data injection attacks in smart grids and propose defense mechanisms to mitigate this type of attacks. To this end, we discuss characteristics of a typical smart grid graph such as planarity. Then we propose three different approaches to find optimal protected meters set: a fast and efficient heuristic algorithm that works well in practice, an approximation algorithm that provides guarantee for the quality of the protected set, and an exact algorithm that finds the optimal solution. Our extensive simulation results show that our algorithms outperform similar existing solutions in terms of different performance metrics.

关键词： Smart grids False data injection Attack Minimum Steiner tree problem

A rare case of obstructive jaundice secondary to pancreatic plasmacytoma

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The Chinese-German Journal of Clinical Oncology 2012年第5期11卷 297-299页

作者： Binesh F akhavan A Navabii H Department of Pathology Yazd Shahid Sadoghi UniversityYazdIran Department of Radiotherapy Yazd Shahid Sadoghi UniversityYazdIran Shahid Sadoghi University of Medical Science YazdIran

Pancreatic plasmacytoma is a rare entity & present with features of mass lesion of *** presented an interesting case of pancreatic plasmacytoma with severe abdominal pain and cholestatic *** case highlights the importance of considering pancreatic plasmacytoma in differential diagnosis of patients with cholestatic jaundice & abdominal pain and that not all pancreatic head mass are adenocarcinoma,so biopsy is advisable.

关键词： plasmacytoma pancreas cholestatic jaundice

Experimental investigation into Fe3O4/SiO2 nanoparticle performance and comparison with other nanofluids in enhanced oil recovery

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Petroleum Science 2019年第3期16卷 578-590页

作者： Yousef Kazemzadeh behnam Dehdari Zahra Etemadan Masoud Riazi Mohammad Sharifi Department of Petroleum Engineering Amirkabir University of Technology Tehran Polytechnic Tehran Iran School of Chemical and Petroleum Engineering Shiraz University Shiraz *** Iran

Nanofluids because of their surface characteristics improve the oil production from reservoirs by enabling different enhanced recovery mechanisms such as wettability alteration,interfacial tension(IFT)reduction,oil viscosity reduction,formation and stabilization of colloidal systems and the decrease in the asphaltene *** the best of the authors’ knowledge,the synthesis of a new nanocomposite has been studied in this paper for the first *** consists of nanoparticles of both SiO2 and *** nanoparticle has its individual surface property and has its distinct effect on the oil production of *** to the previous studies,Fe3O4 has been used in the prevention or reduction of asphaltene precipitation and SiO2 has been considered for wettability alteration and/or reducing IFTs in enhanced oil *** to the experimental results,the novel synthesized nanoparticles have increased the oil recovery by the synergistic effects of the formed particles markedly by activating the various mechanisms relative to the use of each of the nanoparticles in the micromodel *** to the results obtained for the use of this nanocomposite,understanding reservoir conditions plays an important role in the ultimate goal of enhancing oil recovery and the formation of stable emulsions plays an important role in oil recovery using this method.

关键词： Enhanced oil recovery Asphaltene precipitation Wettability alteration Interfacial tension reduction Fe3O4/SiO2 nanofluid

Prediction of the load-carrying capacity of reinforced concrete connections under post-earthquake fire

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第6期22卷 441-466页

作者： Aydin SHISHEGARAN Mehdi MORADI Mohammad Ali NAGHSH behnam KARAMI Arshia SHISHEGARAN School of Civil Engineering Iran University of Science and TechnologyTehranIran Institute of Structural Mechanics Bauhaus-Universitat WeimarWeimar 99423Germany School of Civil Engineering Isfahan UniversityIsfahanIran School of Civil Engineering Isfahan University of TechnologyIsfahanIran International Institute of Earthquake Engineering and Seismology TehranIran 不详

Finding out the most effective parameters relating to the resistance of reinforced concrete connections(RCCs)is an important topic in structural *** this study,first,a finite element(FE)model is developed for simulating the performance of RCCs under post-earthquake fire(PEF).Then surrogate models,including multiple linear regression(MLR),multiple natural logarithm(Ln)equation regression(MLn ER),gene expression programming(GEP),and an ensemble model,are used to predict the remaining load-carrying capacity of an RCC under *** statistical parameters,error terms,and a novel statistical table are used to evaluate and compare the accuracy of each surrogate *** to the results,the ratio of the longitudinal reinforcement bars of the column(RLC)has a significant effect on the resistance of an RCC under *** the value of this parameter from 1%to 8%can increase the residual load-carrying capacity of an RCC under PEF by 492.2%when the RCC is exposed to fire at a temperature of 1000°***,based on the results,the ensemble model can predict the residual load-carrying capacity with suitable accuracy.A safety factor of 1.55 should be applied to the results obtained from the ensemble model.

关键词： Reinforced concrete connection(RCC) Post-earthquake fire(PEF) Surrogate models Load-carrying capacity Gene expression programming(GEP) Ensemble model

Experimental evaluation of blanking and piercing of PVC based composite and hybrid laminates

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Advances in Manufacturing 2016年第3期4卷 248-256页

作者： Vahid Zal Hassan Moslemi Naeini Ahmad Reza Bahramian behnam Abbaszadeh Faculty of Mechanical Engineering Tarbiat ModaresUniversity Tehran Iran Faculty of Chemical Engineering Tarbiat ModaresUniversity Tehran Iran

Blanking is one of the high speed processes to produce fiat products from sheets economically. In order to expand this process to new materials, the blanking of polyvinyl chloride （PVC）/fiberglass thermoplastic com- posite laminates and composite/aluminum hybrid laminates was investigated. The laminates were produced by the film stacking procedure and then blanked by circular die and punches. The blanking process was done in two levels of clearance including 4% and 8% of the laminates thickness, two levels of punch speed including 40 mm/min and 200 mm/min and at two levels of temperature （room tem- perature and 80 ℃） for both composite and hybrid laminates. The effects of the parameters on the maximum blanking force, cutting energy, and quality and precision of sheared edges were studied. Cutting mechanism for blanking in different conditions was explained. It was concluded that at room temperature, blanked composite and hybrid laminates had a high quality of sheared edges but at elevated temperature, although the maximum blanking force was reduced, the quality of sheared edge was reduced significantly.

关键词： Composite laminate Hybrid laminate Blanking Fiberglass Polyvinyl chloride (PVC)

Validation of nutritional risk index method against patientgenerated subjective global assessment in screening malnutrition in colorectal cancer patients

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Chinese Journal of Cancer Research 2013年第5期25卷 544-548页

作者： Elnaz Faramarzi Reza Mahdavi Mohammad Mohammad-Zadeh behnam Nasirimotlagh Student research committee Tabriz University of Medical Sciences Nutrition Research Center Tabriz University of Medical Sciences Department of Radiotherapy Imam Khomeini HospitalTabriz University of Medical Sciences

Objective：To validate malnutrition screening tool of nutrition risk index （NRI） against patent-generated subjective global assessment （PG-SGA） as a gold standard tool in colorectal cancer patients before ***：Nutritional status of 52 volunteer colorectal cancer patients with a mean age of 54.1±16.8 years who referred to radiotherapy center were assessed by PG-SGA （gold standard method） and *** albumin levels of patients were determined by colorimetric method.A contingency table was used to determine the sensitivity,specificity,and predictive value of the NRI in screening patients at risk of malnutrition,in comparison with the PG-SGA in patients before ***：The findings of PG-SGA and NRI showed that 52％ and 45％ of patients in our study were moderately or severely malnourished *** NRI had a sensitivity of 66％ and a specificity of 60％ against *** positive predictive value was 64％ and the negative predicative value was 62％.The agreement between NRI and PG-SGA was statistically insignificant （kappa =0.267; P＞0.05）.Conclusions：The findings of present study showed that the prevalence of malnutrition was high in patients with colorectal ***,NRI method had low sensitivity and specificity in assessing nutritional status of patients with *** seems that the combination of anthropometric,laboratory parameters and a subjective scoring system may be helpful tools in screening of malnutrition in cancer patients.

关键词： Colorectal cancer patients malnutrition patient-generated subjective global assessment nutrition risk index (NRI)