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CHARACTEIZATIONS OF WOVENT g-FRAMES AND WEAVING g-FRAMES IN HILBERT SPACESS AND C^(*)-MODULES

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Acta Mathematica Scientia 2023年第6期43卷 2471-2482页

作者： amir khosravi Mohammad Reza FARMANI Faculty of Mathematical Sciences and Computer Kharazmi University599 Taleghani Ave.Tehran 15618Iran

In this paper,using Parseval frames we generalize Sun’s results to g-frames in Hilbert C^(*)-modules.Moreover,for g-frames in Hilbert spaces,we present some characterizations in terms of a family of frames,not only for orthonormal bases.Also,we have a note about a comment and a relation in the proof of Proposition 5.3 in[D.Li et al.,On weaving g-frames for Hilbert spaces,Complex Analysis and Operator Theory,2020].Finally,we have some results for g-Riesz bases,woven and P-woven g-frames.

关键词： g-frame fusion frame woven frame Riesz basis g-Riesz basis

APPROXIMATE DUALITY OF g-FRAMES IN HILBERT SPACES

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Acta Mathematica Scientia 2014年第3期34卷 639-652页

作者： amir khosravi Morteza MIRZAEE AZANDARYANI Faculty of Mathematical Sciences and Computer Kharazmi (Tarbiat Moallem) University599 Taleghani Ave.Tehran 15618Iran Faculty of Mathematical Sciences and Computer Kharazmi (Tarbiat Moallem) University599 Taleghani AveTehran 15618Iran

In this article, we introduce and characterize approximate duality for g-frames. We get some important properties and applications of approximate duals. We also obtain some new results in approximate duality of frames, and generalize some of the known results in approximate duality of frames to g-frames. We also get some results for fusion frames, and perturbation of approximately dual g-frames. We show that approximate duals are stable under small perturbations and they are useful for erasures and reconstruction.

关键词： Frame g-frame approximate duality perturbation reconstruction

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Brain-derived neurotrophic factor in patients with advanced age-related macular degeneration

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International Journal of Ophthalmology(English edition) 2015年第5期8卷 991-995页

作者： Mehrdad Afarid Mohammad Torabi-Nami Alijan Nemati amir khosravi Mahyar Malekzadeh Department of Ophthalmology Poostchi Eye Research CenterSchool of MedicineShiraz University of Medical Sciences Department of Neuroscience School of Advanced Medical Sciences and TechnologiesShiraz University of Medical Sciences Poostchi Eye Research Center Shiraz University of Medical Sciences Student Research Committee Shiraz University of Medical Sciences and Poostchi Eye Research CenterSchool of MedicineShiraz University of Medical Sciences Institute for Cancer Research School of MedicineShiraz University of Medical Sciences

AIM: To investigate the serum level of the brain derived neurotrophic factor (BDNF) in age -related macular degeneration (AMD) and healthy control subjects. The disruption in the tight balance of neuroinflammatory and neuroprotective processes in an immune -privileged site like retina is proposed to contribute to the pathogenesis of AMD. One of the main neuroprotective mediators in the central nervous system Is BDNF with its serum level notably affected in several neurodegenerative disorders. METHODS: Thirty-six patients'with AMD and 36 age-matched controls were enrolled in this study. The serum level of BDNF was measured using the enzyme -linked immunosorbent assay method. Results were analyzed to compare case and control values. Comparisons were also made between the BDNF level of wet- vsdry-AMD, and male vs female patients and controls. Analysis of variance (ANOVA) and Student's t-test were employed to analyze the data. RESULTS: The mean BDNF levels in AMD group were significantly higher than the control group. Furthermore, our analysis revealed greater BDNF values in all AMD subgroups compared to controls (P=0.004, 0.005, 0.001 and 0.02 for male wet-AMD, male dry-AMD, female wetAMD and female dry-AMD vscontrols, respectively). The BDNF level however did not vary between wet- and dryAMD patients (P=0.74). While within-group comparisons in males and females of AMD and control groups did not show any difference in BDNF (P=0.16, 0.64 and 0.85 for wet -AMD, dry -AMD and control groups, respectively), between -group data showed a higher mean BDNF in both male and female AMD subjects than their peer controls. CONCLUSION: This study demonstrated that the serum BDNF level is different in patients with AMD as compared to subjects without AMD. Future attempts should be done to unravel beneficial or deleterious effect of this neurotrophin in the pathogenesis of AMD.

关键词： age-related macular degeneration brain-derived neurotrophic factor serum level pathogenesis

Shear stress distribution prediction in symmetric compound channels using data mining and machine learning models

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Frontiers of Structural and Civil Engineering 2020年第5期14卷 1097-1109页

作者： Zohreh SHEIKH KHOZANI Khabat khosravi Mohammadamin TORABI amir MOSAVI Bahram REZAEI Timon RABCZUK Institute of Structural Mechanics Bauhaus Universität-WeimarWeimar D-99423Germany Department of Watershed Management Engineering Faculty of Natural ResourcesSari Agricultural Science and Natural Resources UniversitySari 48181Iran Department of Civil and Environmental Engineering Idaho State UniversityPocatelloID 83209USA School of the Built Environment Oxford Brookes UniversityOxford OX30BPUK Kando Kalman Faculty of Electrical Engineering Obuda UniversityBudapest 1034Hungary Department of Civil Engineering Bu-Ali Sina UniversityHamedan 65178Iran

Shear stress distribution prediction in open channels is of utmost importance in hydraulic structural engineering as it directly affects the design of stable channels.In this study,at first,a series of experimental tests were conducted to assess the shear stress distribution in prismatic compound channels.The shear stress values around the whole wetted perimeter were measured in the compound channel with different floodplain widths also in different flow depths in subcritical and supercritical conditions.A set of,data mining and machine learning algorithms including Random Forest(RF),M5P,Random Committee,KStar and Additive Regression implemented on attained data to predict the shear stress distribution in the compound channel.Results indicated among these five models;RF method indicated the most precise results with the highest R2 value of 0.9.Finally,the most powerful data mining method which studied in this research compared with two well-known analytical models of Shiono and Knight method(SKM)and Shannon method to acquire the proposed model functioning in predicting the shear stress distribution.The results showed that the RF model has the best prediction performance compared to SKM and Shannon models.

关键词： compound channel machine learning SKM model shear stress distribution data mining models

A laboratory investigation of bed-load transport of gravel sediments under dam break flow

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International Journal of Sediment Research 2021年第2期36卷 229-234页

作者： Khabat khosravi amir Hooshang Nezamivand Chegini James Cooper Luca Mao Mahmood Habibnejad Kaka Shahedi Andrew Binns Department of Civil Engineering University of Guilan Department of Watershed Management Engineering Sari Agricultural Science and Natural Resources University School of the Built Environment Heriot-Watt University Edinburgh Campus Department of Geography and Planning School of Environmental Sciences University of Liverpool School of Geography University of Lincoln School of Engineering University of Guelph

Dam break flows and resulting river bed erosion can have disastrous impacts on human safety, infrastructure, and environmental quality. However, there is a lack of research on the mobility of non-uniform sediment mixtures resulting from dam break flows and how these differ from uniform sized sediment. In this paper, laboratory flume experiments revealed that coarse and fine fractions in non-uniform sediment had a higher and a lower bed-load parameter, respectively, than uniform sediments of the same size. Thus, the finer fractions were more stable and the coarser fractions were more erodible in a nonuniform bed compared to a uniform-grained bed. These differences can be explained by the hiding and protrusion of these fractions, respectively. By investigating changes in mobility of the mixed-size fractions with reservoir water levels, the results revealed that at low water levels, when the coarser fractions were only just mobile, the bed-load parameter of the finer fractions was higher than the coarser fractions. The opposite was observed at a higher water level, when a significant proportion of the coarsest fractions was mobilized. The higher protrusion of these grains had an important effect on their mobility relative to the finer grains. The transported sediment on these mixed-sized beds was coarser than the initial bed sediment, and became coarser with an increase in reservoir water level.

关键词： Dam break Bed-load transport Gravel Laboratory flume

Uniform and graded bed-load sediment transport in a degrading channel with non-equilibrium conditions

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International Journal of Sediment Research 2020年第2期35卷 115-124页

作者： Khabat khosravi amir H.N.Chegini James R.Cooper Prasad Daggupati Andrew Binns Luca Mao School of Engineering University of Guelph School of the Built Environment Heriot-Watt University Department of Geography and Planning School of Environmental SciencesUniversity of Liverpool Department of Geography University of Lincoln

Bed-load transport plays a critical role in river morphological change and has an important impact on river ecology.Although there is good understanding of the role of the variation of river bed grain size on transport dynamics in equilibrium conditions,much less is understood for non-equilibrium conditions when the channel is either aggrading or degrading.In particular,the relative role of different grain sizes in the promotion and hindering of the transport of coarse and fine fractions in a degrading channel has yet to be investigated.The current study attempts to provide new understanding through a series of flume experiments done using uniform and graded sediment particles.The experiments revealed coarser grain-size fractions for a poorly-sorted sediment,relative to uniform-sized sediment,reduced the transport of finer grains and finer fractions enhanced the transport of coarse grains.This hinderingpromotion effect,caused by relative hiding and exposure of finer and coarse fractions,increased with bed slope and decreased with relative submergence.In particular,as relative submergence increased,the graded fractions tended towards behaving more like their unifo rm-sized counterparts.Also,the bed-load parameter of the graded fractions increased more with a rise in bed slope than observed for the uniformsized counterparts.These results revealed,for degrading channel conditions,such as downstream of a dam,bed-load equations developed for uniform bed sediment are inappropriate for use in natural river systems,particularly in mountain streams.Furthermore,changes in river bed composition due to activities that enhance the input of hill-slope sediment,such as fire,logging,and agricultural development,are likely to cause significant changes in river morphology.

关键词： Graded sediment Exposure Hiding Flume experiments Non-equilibrium

强迫症患者、强迫型人格障碍患者和健康对照者之间的认知灵活性和计划能力比较（英文）

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上海精神医学 2016年第1期28卷 28-34页

作者： Negin PAAST Zohreh khosravi amir Hossein MEMARI Monir SHAYESTEHFAR Mohammad ARBABI Neuroscience Institute Sports Medicine Research Center Tehran University of Medical Sciences Department of Psychology Alzahra University Psychiatry and Psychology Research Center Tehran University of Medical Sciences

背景:强迫症患者(Obsessive Compulsive Disorder,OCD)与强迫型人格障碍患者(Obsessive Compulsive Personality Disorder,OCPD)的认知功能还没有得到充分的研究。目标:验证OCD和OCPD患者的认知灵活性和计划能力。方法:本研究在德黑兰... 详细信息

背景:强迫症患者(Obsessive Compulsive Disorder,OCD)与强迫型人格障碍患者(Obsessive Compulsive Personality Disorder,OCPD)的认知功能还没有得到充分的研究。目标:验证OCD和OCPD患者的认知灵活性和计划能力。方法:本研究在德黑兰心理咨询门诊选定了25例OCD患者和20例OCPD患者,他们在既往两周都没有服药,并且从大学工作人员和当地社区居民中选定了25名健康对照者。对所有参与者均进行28项一般健康问卷(28-item version of the General Health Questionnaire,GHQ-28)、威斯康星卡片分类测验(Wisconsin Card Sorting Test,WCST)、和伦敦塔试验(Tower of London test,TOL))。本研究运用WCTS的两个测量指标(持续错误数和完成分类数)评估认知灵活性以及TOL的三个测量指标(12个试验总共的移动次数、总应答时和计划时间)评估计划能力。结果:2组患者的当前心理困扰程度显著高于对照组。在控制人口学因素和心理困扰水平后,OCD患者和OCPD患者在WCST测试中比对照组更容易出现持续性错误,而OCD患者(不包括OCPD患者)的完成分类数比对照组显著减少。OCD患者和OCDP患者都比对照组需要更多的移动次数来完成12项TOL任务,并且OCD患者比OCPD患者和对照组需要花更长的时间来完成任务。结论:与健康对照组相比,OCD和OCPD患者的认知灵活性和计划能力都有所受损,并且OCD和OCPD患者之间的认知功能测试也存在一些差异。我们需要对OCD和OCPD患者进行长期随访研究评估在强迫症状严重性加重与减轻时认知功能的改变,从而决定此类认知评估指标对于强迫症是否有诊断或临床关联性。

关键词：强迫症强迫型人格障碍执行功能神经心理学伊朗

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Human Epididymis Protein-4 Gene Expression as a Biomarker in Patients with Ovarian Cancer in Iran

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Open Journal of Clinical Diagnostics 2017年第3期7卷 83-90页

作者： Arezo Shahi Naghmeh Bahrami Atefeh Fakharian Somayeh Sharifynia Elham Moslemi amir Izadi Adnan khosravi Hamidreza Jamaati Abdolreza Mohamadnia Department of Biology Faculty of Basic Sciences Islamic Azad University North Tehran Branch Tehran Iran Craniomaxillofacial Research center Tehran University of Medical Sciences Tehran Iran Oral and Maxillofacial Surgery Department School of Dentistry Tehran University of Medical Sciences Tehran Iran Chronic Respiratory Diseases Research Center National Research Institute of Tuberculosis and Lung Diseases (NRITLD) Shahid Beheshti University of Medical Sciences Tehran Iran Clinical Tuberculosis and Epidemiology Research Center National Research Institute of Tuberculosis and Lung Diseases (NRITLD) Shahid Beheshti University of Medical Sciences Tehran Iran Department of Biology Islamic Azad University Tehran East Tehran Iran Young Researchers and Scholars Club Islamic Azad University Tehran East Tehran Iran Bunge Oxir Research Institute Iran Tobacco Prevention and Control Research Center National Research Institute of Tuberculosis and Lung Diseases (NRITLD) Shahid Beheshti University of Medical Sciences Tehran Iran Virology Research Center National Research Institute of Tuberculosis and Lung Diseases (NRITLD) Shahid Beheshti University of Medical Sciences Tehran Iran Department of Biotechnology School of Advanced Technologies in Medicine Shahid Beheshti University of Medical Sciences Tehran Iran

Introduction: Ovarian cancer is one of the most common malignancies in women and the fifth cause of cancer-related deaths in women worldwide. Contrary to the challenges in developing new clinical markers using the conventional methods, recent advances in genomics and proteomics have led to identification of candidate and promising biomarkers for the diagnosis of ovarian cancer. Human epididymis protein 4 (HE4) is such a marker that has recently been reported to correlate with recurrence or progression of epithelial ovarian cancer. The purpose of this study was to measure the expression level of HE4 gene in women with ovarian cancer. Methodology: We evaluated and compared paraffin-embedded tissue samples of 20 ovarian cancer patients with 10 samples from healthy individuals. RNA was initially extracted from the samples and cDNA was synthetized. Gene expression level was then measured using real-time polymerase chain reaction (PCR). Results: Our results demonstrated that HE4 gene expression level was significantly higher in samples of patients with ovarian cancer compared with samples from healthy individuals. Moreover, higher levels of HE4 gene expression were associated with more advanced disease and larger tumor size. Conclusion: HE4 gene over-expression has the potential to be used as a biomarker for detecting early-stage ovarian cancer in women. Future more comprehensive studies are needed to confirm our findings.

关键词： Ovarian Neoplasms Genomics Tumor Biomarkers HE4 Protein