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The Journal of Biomedical Research 2011年第5期25卷 362-367页

作者： ali ahadi alireza Partoazar Mohammad Hassan Abedi Khorasgani Seyed Vahid Shetab Boushehri Department of Physiology School of MedicineTehran University of Medical Sciences Department of Pharmacology School of MedicineTehran University of Medical Sciences Legal Medicine Organization of Iran Iran Department of Medical Nanotechnology School of MedicineTehran University of Medical Sciences

Liquid-liquid extraction-thin layer chromatography （LLE-TLC） has been a common and routine combined method for detection of drugs in biological materials. Solid-phase extraction （SPE） is gradually replacing the tra- ditional LLE method. High performance thin layer chromatography （HPTLC） has several advantages over TLC. The present work studied the higher efficiency of a new SPE-HPTLC method over that of a routine LLE-TLC method, in extraction and detection of urinary morphine. Fifty-eight urine samples, primarily identified as mor- phine-positive samples by a strip test, ＇were re-screened by LLE-TLC and SPE-HPTLC. The results of LLE-TLC and SPE-HPTLC were then compared with each other. The results showed that the SPE-HPTLC detected 74% of total samples as morphine-positive samples whereas the LLE-TLC detected 48% of the same samples. We further discussed the effect of codeine abuse on TLC analysis of urinary morphine. Regarding the importance of morphine detection in urine, the present combined SPE-HPTLC method is suggested as a replacement method for detection of urinary morphine by many reference laboratories.

关键词： morphine detection liquid-liquid extraction thin-layer chromatography solid-phase extraction highperformance thin layer chromatography

Assessment of the effects of intrastromal injection of adipose-derived stem cells in keratoconus patients

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International Journal of Ophthalmology(English edition) 2023年第6期16卷 863-870页

作者： Shahrokh Ramin ali Abbasi Masoumeh ahadi Lina Moallemi Rad Farzad Kobarfad Department of Optometry School of Rehabilitation SciencesIncubation Center for Pharmaceutical Technology(ICPT)Shahid Beheshti University of Medical SciencesCell Therapy DepartmentRed Crescent Pharmaceutical and Clinical ComplexTehran ***Iran Student Research Committee and Department of Optometry School of Rehabilitation SciencesShahid Beheshti University of Medical SciencesTehran ***Iran Department of Molecular and Cell Biology Faculty of Basic SciencesUniversity of MazandaranBabolsar ***Iran Department of Medicinal Chemistry Shahid Beheshti School of PharmacyTehran ***Iran

·AIM: To evaluate the efficacy and safety of intrastromal transplantation of adipose-derived stem cells(ASCs) in keratoconus patients.·METHODS: This study was conducted on 8 eyes of 8 patients with moderate to severe keratoconus. In the patients, ophthalmic assessments including visual acuity, refraction, slit lamp examination, fundoscopy, corneal topography, and confocal microscopy were performed. Autologous stem cells were used. The isolated stem cells were injected into the corneal stroma by using femtosecond laser. Surgical procedure was similar to intracorneal ring implantation. All patients were re-assessed 1, 3, and 6mo after surgery.·RESULTS: The baseline mean visual acuity was 0.48±0.18 and improved to 0.66±0.17 after surger y and final acuity increased by 1.85±0.80 lines(P=0.001).The mean spherical refraction of patients improved 0.34 ± 0.35 D(P=0.039), and the mean cylindrical refraction of patients improved 0.84±0.23 D(P=0.016). The mean flat keratometry decreased 0.78±0.71 D(P=0.017), and the mean steep keratometry decreased 0.59±0.68 D(P=0.023). The mean central corneal thickness of patients improved of 6.29±4.47 μm(P=0.03). The mean keratocyte density at the anterior and middle stroma of cornea increased(Pality is safe, and patients do not have any complications.

关键词： adipose-derived stem cells stromal keratocyte cellular therapy keratoconus

Functional roles of lncRNAs in the pathogenesis and progression of cancer

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Genes & Diseases 2021年第4期8卷 424-437页

作者： alireza ahadi Department of Medical Genetics School of MedicineShahid Beheshti University of Medical SciencesTehran198396-3113Iran

Long noncoding RNAs(lncRNAs)act as regulators of gene expression and pivotal transcriptional regulators in cancer cells via diverse *** involves a variety of pathological and biological activities,such as apoptosis,cell proliferation,metastasis,and *** using microarray and RNA sequencing,it was identified that dysregulation of lncRNAs affects the tumorigenesis *** together,these lncRNAs are putative biomarker and therapeutic target in human *** this review,I discuss the latest finding regarding the dysregulation of some important lncRNAs and their diverse mechanisms of these lncRNAs in the pathogenesis and progression of certain cancers;also,I summarize the possible roles of lncRNAs in clinical application for diagnosis and prognosis of cancer.

关键词： Biomarker Cancer Dysregulation LncRNA NcRNA

A Comparative Study of the Application of Electronic Data Interchange and Internet Technology to Business Process Reengineering

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Tsinghua Science and Technology 2004年第4期9卷 489-496页

作者： Hamid Reza ahadi School of Economics and Management Tsinghua University Beijing 100084 China

This study investigates the role of information technology in business process reengineering (BPR) implementation. To increase the prospects of successful BPR implementation, the role of information technology in BPR should be thoroughly investigated to find the logical relationships between information technology and BPR. This study used a survey methodology to gather information from 72 BPR programs. The results show that different information technologies, such as those examined in this study, electronic data interchange (EDI) and Internet, provide different capabilities and can be useful in different ways and for different purposes. Lack of attention to these relationships may be due to the unacceptable high implemen-tation failure rate in the previous BPR efforts.

关键词： business process reengineering organizational enablers information technology

Reliability evaluation of future photovoltaic systems with smart operation strategy

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Frontiers in Energy 2016年第2期10卷 125-135页

作者： Amir ahadi Hosein HAYATI SeyedMohsen MIRYOUSEFI AVAL Young Researchers and Elite Club Ardabil Branch Islamic AzadUniversity Ardabil *** Iran

This paper investigates a new operation strategy for photovoltaic （PV） systems, which improves the overall reliability of the system as a result of the improvement in the reliability of the critical components. First, a mathematical model is proposed using the fault tree analysis （FTA） to estimate the reliability of the PV systems in order to find the suitable maintenance strategies. The implementations demonstrate that it is essential to employ smart maintenance plans and monitor the identified most critical components of PV systems. Then, an innovative analytical method based on the Markov process is presented to model smart operation plans in PV systems. The impact of smart operation strategy on the PV systems is then evaluated. The objective of this paper is to develop plans for improving the reliability of PV systems. A series of case studies have been conducted to demonstrate the importance of smart operation well as the applicability and method. strategies for PV systems as feasibility of the proposed

关键词： smart operation strategy renewable energy,fault tree analysis (FTA) Markov model

New concept and procedure for reliability assessment of an IEC 61850 based substation and distribution automation considering secondary device faults

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Frontiers in Energy 2015年第4期9卷 387-398页

作者： Hosein HAYATI Amir ahadi Seyed Mohsen MIRYOUSEFI AVAL Young Researchers and Elite Club Ardabil Branch Islamic AzadUniversity Ardabil 56131-56491 Iran

Smart grid is a power grid consists of extensive monitoring systems which deal with the monitoring of attributes such as current, voltage, power, and energy at distribution transformers, substations transformers, distri- bution switching devices and smart meters. Smart grid with advanced communication technologies can be used for several purposes such as efficiency and reliability improvement. IEC 61850 is the core standard in the smart grid domain for distribution and substation automa- tion. This paper introduces a vision of modem substation and distribution systems using the IEC 61850. Network operators mainly assume that the modem substation and distribution systems based on the IEC 61850 are reliable for a long-time of operation. However, similar to any other systems, the implemented IEC 61850 might fail because of the operational failures or aging failures. This paper proposes a novel method for reliability evaluation of modem substation and distribution systems. A typical IEC 61850 based distribution and substation system is devel- oped and analyzed using the proposed method. The fault tree analysis （FTA） is used to quantify the reliability of the system. The technique is implemented and demonstrated on the Roy Billinton test system （RBTS）. The analysis is further extended on a 400/63 kV substation with a breaker- and-a-half configuration. In addition, the technique proves to be robust under different operations. The results verify the feasibility and applicability of the proposed method.

关键词： IEC 61850 reliability assessment fault treeanalysis

Generating capacity adequacy evaluation of large-scale, grid-connected photovoltaic systems

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Frontiers in Energy 2016年第3期10卷 308-318页

作者： Amir ahadi Seyed Mohsen MIRYOUSEFI AVAL Hosein HAYATI Young Researchers and Elite Club Ardabil Branch Islamic Azad University Ardabil *** Iran

Large-scale, grid-connected photovoltaic sys- tems have become an essential part of modem electric power distribution systems. In this paper, a novel approach based on the Markov method has been proposed to investigate the effects of large-scale, grid-connected photovoltaic systems on the reliability of bulk power systems. The proposed method serves as an applicable tool to estimate performance （e.g., energy yield and capacity） as well as reliability indices. The Markov method frame- work has been incorporated with the＇ multi-state models to develop energy states of the photovoltaic systems in order to quantify the effects of the photovoltaic systems on the power system adequacy. Such analysis assists planners to make adequate decisions based on the economical expectations as well as to ensure the recovery of the investment costs over time. The failure states of the components of photovoltaic systems have been considered to evaluate the sensitivity analysis and the adequacy indices including loss of load expectation, and expected energy not supplied. Moreover, the impacts of transitions between failures on the reliability calculations as well as on the long- term operation of the photovoltaic systems have been illustrated. Simulation results on the Roy Billinton test system has been shown to illustrate the procedure of the proposed frame work and evaluate the reliability benefits of using large-scale, grid-connected photovoltaic system on the bulk electric power systems. The proposed method can be easily extended to estimate the operating and maintenance costs for the financial planning of the photovoltaic system projects.

关键词： adequacy assessment Markov method large-scale grid-connected photovoltaic(PV) systems long-termoperation

Speaker adapted dynamic lexicons containing phonetic deviations of words

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第10期10卷 1461-1475页

作者： Bahram VAZIRNEZHAD Farshad ALMASGANJ Seyed Mohammad ahadi Ari CHANEN Biomedical Engineering Department Amirkabir University of Technology Language and Knowledge Management Research Lab School of Information TechnologiesUniversity of Sydney Electrical Engineering Department Amirkabir University of Technology

Speaker variability is an important source of speech variations which makes continuous speech recognition a difficult *** automatic speech recognition(ASR) models to the speaker variations is a well-known strategy to cope with the *** all such techniques focus on developing adaptation solutions within the acoustic models of the ASR *** variations of the acoustic features constitute an important portion of the inter-speaker variations,they do not cover variations at the phonetic *** variations are known to form an important part of variations which are influenced by both micro-segmental and suprasegmental ***-speaker phonetic variations are influenced by the structure and anatomy of a speaker's articulatory system and also his/her speaking style which is driven by many speaker background characteristics such as accent,gender,age,socioeconomic and educational *** effect of inter-speaker variations in the feature space may cause explicit phone recognition *** errors can be compensated later by having appropriate pronunciation variants for the lexicon entries which consider likely phone misclassifications besides *** this paper,we introduce speaker adaptive dynamic pronunciation models,which generate different lexicons for various speaker clusters and different ranges of speech *** models are hybrids of speaker adapted contextual rules and dynamic generalized decision trees,which take into account word phonological structures,rate of speech,unigram probabilities and stress to generate pronunciation variants of *** the set of speaker adapted dynamic lexicons in a Farsi(Persian) continuous speech recognition task results in word error rate reductions of as much as 10.1% in a speaker-dependent scenario and 7.4% in a speaker-independent scenario.

关键词： Pronunciation models Continuous speech recognition Lexicon adaptation

A novel method for reliability and risk evaluation of wind energy conversion systems considering wind speed correlation

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Frontiers in Energy 2016年第1期10卷 46-56页

作者： Seyed Mohsen MIRYOUSEFI AVAL Amir ahadi Hosein HAYATI Young Researchers and Elite Club Ardabil Branch Islamic AzadUniversity Ardabil Iran

This paper investigates an analytical approach for the reliability modeling of doubly fed induction generator （DFIG） wind turbines. At present, to the best of the authors＇ knowledge, wind speed and wind turbine generator outage have not been addressed simultaneously. In this paper, a novel methodology based on the Weibull- Markov method is proposed for evaluating the probabil- istic reliability of the bulk electric power systems, including DFIG wind turbines, considering wind speed and wind turbine generator outage. The proposed model is presented in terms of appropriate wind speed modeling as well as capacity outage probability table （COPT）, considering component failures of the wind turbine generators. Based on the proposed method, the COPT of the wind farm has been developed and utilized on the IEEE RBTS to estimate the well-known reliability and sensitive indices. The simulation results reveal the importance of inclusion of wind turbine generator outage as well as wind speed in the reliability assessment of the wind farms. Moreover, the proposed method reduces the complexity of using analytical methods and provides an accurate reliability model for the wind turbines. Furthermore, several case studies are considered to demonstrate the effectiveness of the proposed method in practical applications.

关键词： doubly-fed induction generator (DFIG) com- posite system adequacy assessment wind speed correlation

Insight into heavy oil recovery of cyclic solvent injection (CSI) utilizing C_(3)H_(8)/CH_(4) and C_(3)H_(8)/CH_(4)/CO_(2)

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Petroleum 2018年第3期4卷 337-346页

作者： Arash ahadi Farshid Torabi Petroleum Systems Engineering University of ReginaSKS4S 0A2Canada

In this study,a sandpack model with porosity and permeability of 32.3%and 9.4 D,and a heavy crude oil with viscosity of 6430 mPa.s were used to represent a typical thin heavy oil ***,different ratios of C3H8 to CH4 stream were prepared and their performance on Cyclic Solvent Injection(CSI)method was examined to quantify the optimum solvent ***,CO2 was introduced to the optimum quantified CH4-C3H8 mixture to investigate the extent to which CSI behavior changes by partially replacement of CH4 with *** showed that ultimate oil recovery factor(RF)increased from 24.3%to 33.4%original oil in place(OOIP)when C3H8 concentration increased from 15 to 50 mol%in the CH4 *** tests with higher C3H8 concentration reached the maximum cyclic recovery with lower number of injection cycles-due to higher solubility of C3H8 compared with *** utilization factor(SUF)data also confirmed this as lesser volume of solvent with higher C3H8 concentration was required to produce *** observations showed that the produced foamy oil lasted longer with higher concentration of C3H8 in the solvent(5 min for 15%C3H8 e 85%CH4 case versus 180min for 50%C3H8 e 50%CH4 case).Upon addition of CO2 to the mixture,the solvent apparent solubility increased and foamy oil flow *** highest cyclic C3H8-CH4 apparent solubility of 0.175 ***/100 *** oil jumped to 0.53 ***/100 *** oil when 35%mole fraction of CO2 replaced *** highest ultimate oil RF of 44.11%OOIP was measured from eight cycle injection of 50%C3H8 e 15%CH4 e 35%*** solvent also benefited from the longest stability of produced-oil foamy shape with recorded time of 217 min(including production time).According to the results of this experimental study,it seems that there is an optimum fraction of C3H8 in CH4 stream injection in heavy oil systems(with viscosity in the vicinity of 6430 mPa s);the concentration beyond which ultimate oil recovery factor

关键词： CSI Solubility Heavy oil Foam stability Light hydrocarbons