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Woody Species Diversity and Forest Structure from Lowland to Montane Forest in Hyrcanian Forest Ecoregion

Journal of Mountain Science 2013年第4期10卷 609-620页

作者： seyed Mohammad JAFARI Shahin ZARRE seyed kazem alavipanah School of Biology and Center of Excellence in Phylogeny of Living Organisms College of Science University of TehranP.O. Box 14155-6455 Tehran Iran School of Biology and Center of Excellence in Phylogeny of Living Organisms College of Science University of TehranTehran Iran Department of Cartography Faculty of Geography University of TehranTehran Iran

Alborz Mountains host Caspian Hyrcanian forest ecoregion along the northern slopes and forest steppe ecoregion in highlands. Hyrcanian forest covers the southeastern part of Caucasus biodiversity hotspot and is of great biogeographic importance. Altitudinal pattern and correlation between woody species biodiversity （DIV）, forest structure （（stem density （DEN）, mean basal area （MBA） and mean height class （MHC）） and disturbance （DIS） were explored along 2,4oo m altitudinal gradient in Hyrcanian relict forest, Central Alborz Mountains. Vegetation changes from lowland forest （LoF） to mid- altitude forest （MiF） and montane forest （MoF） in this area. The altitudinal gradient was divided into twelve 200 m elevational belts. Point centered quarter method （PCQM） with 96 sampling points and 83 vegetation samples by plot method （PM） were used to record field data. Shannon-Wiener index and Pearson coefficient were used for diversity and correlation analysis. The results showed that DEN decreased linearly, MBA and MHC showed relatively hump shaped and DIS showed a reverse hump shaped pattern of change along altitudinal gradient. Woody species diversity decreased non-steadily from LoF to MoF. Transitional vegetations of Carpinus-Fagus and Fagus-Quercus represented higher diversity of woody taxa compared to adjacent homogenous communities. Significant correlation was observed between altitude and all parameters： DEN with MBA, DIS and DIV; MBA with DIS; MHC with DIS along with DIV; and DIS with DIV at the study area scale. Surprisingly,correlation between studied parameters differed within each vegetation type. Altitude probably acts as a proxy for human and environmental driving forces in this area. Stability of warm and wet condition, season length, soil depth along with forest accessibility probably influences the altitudinal pattern of the studied parameters. Disturbance affects forest structure and consequently diversity; especially in lowlands. The obtained results recommend

关键词： Alborz Mountains Biodiversity ForestMensuration Hyrcanian forest Disturbance

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A new approach to LST modeling and normalization under clear-sky conditions based on a local optimization strategy

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International Journal of Digital Earth 2022年第1期15卷 1833-1854页

作者： Majid Kiavarz Mohammad Karimi Firozjaei seyed kazem alavipanah Quazi K.Hassan Yoann Malbéteau Si-Bo Duan Department of Remote Sensing and GIS University of TehranTehranIran Geomatics Engineering Schulich School of EngineeringUniversity of CalgaryCalgaryCanada Center for Remote Sensing Applications Mohammed VI Polytechnic University (UM6P)Ben GuerirMorocco Key Laboratory of Agricultural Remote Sensing Ministry of Agriculture/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijingPeople’s Republic of China

The normalization of LST relative to environmental parameters is of great importance in various environmental applications. The purpose of this study was to develop a new approach for LST normalization relative to environmental variables. These included topographic variables (i.e. solar irradiance and near-surface temperature lapse rate (NSTLR)) as well as biophysical properties (i.e. vegetation,wetness,and albedo). The study was conducted in two phases,namely (1) using global and (2) local optimization strategies to calculate the regression coefficients of environmental variables in the partial least squares regression (PLSR) and build the non-linear linking model in the random forest regression (RFR). The RMSEs between actual LST and modeled LST based on the global and local optimization strategies using PLSR (RFR) were 2.202 (0.935) and 0.939 (0.835) °C,respectively. The results showed that RFR had higher efficiency than PLSR in normalizing LST. Moreover,the local optimization method outperformed the global optimization method in terms of normalization accuracy. The results of this study could be very useful in many environmental applications such as identifying thermal anomalies,and surface anthropogenic heat island modeling.

关键词： Normalization land surface temperature environmental variables partial least squares random forest local strategy

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Comparison of different turbulence models in predicting cohesive fluid mud gravity current propagation

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International Journal of Sediment Research 2020年第5期35卷 504-515页

作者： seyed-Mohammad-kazem Emami Sayed-Farhad Mousavi Khosrow Hosseini Hesam Fouladfar Majid Mohammadian Faculty of Civil Engineering University of Semnan Iran Water & Power Resources Development Company 3. Department of Civil Engineering University of Ottawa

A numerical study of propagation of cohesive fluid mud gravity currents in the form of lock-exchange was done using the OpenFOAM open source *** Eulerian approach solution for three separate phases was developed by incorporating a rheological model to predict the front position of cohesive fluid mud gravity *** model also simulates features in the complete movement phases including slumping,self-similar,and viscous in which the dynamics of propagation are affected by the balance of viscous and buoyancy forces,and the inertia force is *** influence of using different turbulence models containing sub-grid scale(SGS),modified SGS,detached eddy simulation(DES),delayeddetached eddy simulation(DDES),Launder-R eece-Rodi(LRR),and k-ε models on the accuracy of simulation results was evaluated by comparing with available experimental *** results show that the selection of the proper turbulence model is one of the most important issues for this type of the numerical *** more efficient turbulence model was suggested and tabulated for each stage of propagation and different selected concentrations of 1,045,1,140,and 1,214 g/*** different turbulence models(except k-ε) lead to front propagation dynamic simulation results that are in good agreement with the experimental measurements in the early stage of propagation for low concentrations,only DES,SGS,and modified SGS are able to capture the Kelvin-Helmholtz instability vortex shapes at the dense fluid interface,which is the main characteristic of the gravity current through the slumping *** calculated accuracies of SGS and modified SGS in predicting gravity current propagation for the both self-similar and viscous phases also are slightly better than DES,DDES,and LRR model *** results of this study confirmed the performance and efficiency of the modified SGS model in which the interaction coefficients between phases are calibrated for the numerical modeling of fluid mud

关键词： Gravity current Turbulence model Numerical simulation Cohesive particles Rheology

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Evaluation of kefir as a potential probiotic on growth performance,serum biochemistry and immune responses in broiler chicks

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Animal Nutrition 2015年第4期1卷 305-309页

作者： Majid Toghyani seyed kazem Mosavi Mehrdad Modaresi Nasir Landy Department of Animal Science Khorasgan Branch Islamic Azad University Young Researchers and Elite Club Khorasgan BranchIslamic Azad University

This experiment was conducted to evaluate the effect of milk or molasses kefir as a probiotic on growth performance, carcass traits, serum biochemistry and humoral immune responses in broiler chickens. A total of 192 one-d-old as hatched broiler chicks(Ross 308) were randomly allotted to 4 treatments, each with 4 replicate pens of 12 chicks. The following treatments were applied: 1) a basal diet(C) and normal drinking water, 2) 2% milk kefir in drinking water, 3) 2% molasses kefir in drinking water, and 4) the diet C supplemented with commercial probiotic. At d 42, eight birds per treatment were killed for determination of carcass traits. Broilers at 28 days of age were bled for measuring antibody titers against Newcastle disease virus(NDV) and avian influenza virus(AIV), at 30 days of age for antibody titers against sheep red blood cell(SRBC), and at 42 days of age for biochemical analysis. Supplementing 2%milk kefir increased body weight of broilers at 28 and 42 days of age(P 0.05) influenced. Broilers supplemented with molasses kefir, had a significantly lower concentration of serum total cholesterol, low density lipoprotein cholesterol and elevated high density lipoprotein cholesterol at 42 days of age(P < 0.05). In conclusion, t

关键词： Antibiotic Milk kefir Molasses kefir Multi-strain probiotic Broilers

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Efficacy of premedication with activated Dimethicone or N-acetylcysteine in improving visibility during upper endoscopy

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World Journal of Gastroenterology 2011年第37期17卷 4213-4217页

作者： seyed Mohammad kazem Hosseini Asl Gholam Reza Sivandzadeh Department of Internal Medicine Nemazee HospitalShiraz University of Medical Sciences

AIM:To assess the efficacy of N-acetylcysteine(NAC) and activated Dimethicone in improving endoscopic mucosal ***:A total of 148 patients were randomly allocated into four groups to receive one of the following premedications:group A:100 mL water alone;group B:activated Dimethicone plus water(up to 100 mL);group C:NAC plus water(up to 100 mL);and group D:activated Dimethicone and NAC plus water(up to 100 mL).A single endoscopist blinded to the patients group assessed the gastric mucosal visibility scores(range 1-4) at four *** sum of the scores from the four sites was considered as the total mucosal visibility score(TMVS).RESULTS:The patients in group B showed a significantly lower TMVS than those of groups A and C(P 0.05).The difference between TMVS of groups C and A was not significant(P > 0.05).CONCLUSION:Premedication with activated Dimethicone 20 min prior to the upper endoscopy leads to the best *** does not improve visualization by itself.

关键词： Dimethicone N-acetylcysteine Simethicone Upper endoscopy

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Microstructure Development after Coiling Process in Low-Si Content TRIP-Assisted Steels

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Journal of Mechanics Engineering and Automation 2013年第10期3卷 650-655页

作者： seyed Mohammad kazem Hosseini Abbass Zarei-Hanzaki Stephen Yue Department of Materials Engineer Faculty of Engineer Imam Khomeini International University 34149 16818 Qazvin Iran School of Metallurgy and Materials Engineer College of Engineering University of Tehran Tehran 14395-731 Iran Department of Mining and Materials Engineering McGill University Quebec H3A 2A 7 Canada

The present work aimed to investigate the effect of coiling process conditions on microstructure development in a low-Si content TRIP （transformation-induced plasticity）-assisted steel after thermomechanical processing. In this framework, compression samples which were deformed above Tnr and then intercritically annealed were held isothermally for different durations at temperatures below bainite transformation start temperature. Microstructure of samples were characterized by optical and electron microscopy, XRD （X-ray diffraction） and M6ssbauer spectroscopy. The results indicated that due to low-silicon content of the present steel, the incomplete bainite reaction phenomena was not observed and, hence, the maximum carbon enrichment of residual austenite was achieved in the samples which held for short durations. It was also shown that the maximum carbon enrichment and volume fraction of residual austenite were achieved at intermediate bainite hold temperature of 450 ℃ as the result of competing phenomena, such as microstructural refinement, dislocation density, carbide precipitation and growth.

关键词： Thermomechanical processing TRIP-steels bainite transformation coiling process retained austenite

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Effects of pre-deformation on microstructure and tensile properties of Al-Zn-Mg-Cu alloy produced by modified strain induced melt activation

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Transactions of Nonferrous Metals Society of China 2016年第9期26卷 2283-2295页

作者： Behzad Mohasel AFSHARI seyed Sajad MIRJAVADI Yousef Askari DOLATABAD Mojtaba AGHAJANI Mohammad kazem Besharati GIVI Mohammad ALIPOUR M.EMAMY School of Mechanical Engineering College of Engineering University of Tehran Department of civil engineering Sirjan University of Technology Department of Industrial Engineering Faculty of Engineering University of Tehran School of metallurgy and materials engineering University of Tehran Faculty of Materials Science and Engineering K.N.Toosi University of Technology Department of Materials Engineering Faculty of Mechanical Engineering University of Tabriz

The effects of Al-8B grain refiner on microstructure and tensile properties of an Al-12Zn-3Mg-2.5Cu alloy produced by modified strain induced melt activation process were investigated. Pre-deformation of 60% was used by hot working at 300 ℃. After pre-deformation, the samples were heated to a temperature above the solidus and below the liquidus point and maintained in the isothermal conditions at three different temperatures（500, 550 and 590 ℃） for varying time（10, 20 and 40 min）. It was observed that strain induced melt activation has caused the globular morphology of α（Al） grains. Microstructural study was carried out on the alloy by using optical microscope and scanning electron microscope in both unrefined and B-refined conditions. The results showed that for the desired microstructures of the alloy during SIMA process, the optimum temperature and time are 550 ℃ and 10 min, respectively. After the T6 heat treatment, the average tensile strengths increased from 278 to 585 MPa and 252 to 560 MPa for samples refined with 3.75% Al-8B before and after SIMA process, respectively. The ultimate strength of SIMA specimens is lower than that of B-refined specimens.

关键词： aluminium alloy casting grain refinement strain induced melt activation semisolid processing tensile properties

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Microfacies, Sedimentary Environment and Sequence Stratigraphy of Gadvan and Darian Formations in the Zagros Basin, South of Semirom, Iran

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Open Journal of Geology 2016年第9期6卷 1169-1186页

作者： Mohammad kazem Hamedanian seyed Hamid Vaziri Mahnaz Amir Shakarami Mehran Arian Naser Arzani Department of Geology Science and Research Branch Islamic Azad University Tehran Iran Department of Geology North Tehran Branch Islamic Azad University Tehran Iran Department of Geology Payam Noor University Isfahan Iran

Gadvan and Darian formations are in the upper part of Khami group that has been deposited in the highland Zagros zone and the southern Margin of Neotethys. These formations outcrop in the south of Semirom (Agh-Dagh Mountain) consist of Orbitolina limestones and marly limestones with a Late Barremian-Aptian age and thickness of 520 meters. Based on field characteristics, petrographic and texture of facies, these rocks consist of Oregonian facies (Urgonian facies) with 12 carbonate microfacies which are deposited in Lagoon, barrier and shallow open marine. The absence of loss and flows of turbidities indicates that carbonate platform of Gadvan and Darian formations in the studied area are (Hmoklinal) platform type. Abundance of rudist (bivalves) and Peloid markers show that there is a Photozoan collection in tropical climates. In the above sedimentary succession, from a sequence stratigraphic perspective, three sedimentary cycles were recognized which deposited in a platform model. The Gadvan Formation overlies on Fahliyan Formation disconformable and is covered by Darian Formation gradual with reducing the amount of marl and increase of limestone. The Kazhdumi Formation is exposed disconformably with hematite nodules and oxidized sediments over the Darian Formation. On the basis of petrographic studies, diagenetic process of Gadvan and Darian formations in the study area includes cementation, the physical and chemical density and replacement processes such as pyritation, ironies and silica. Porosity observed in the study area is mainly inter-granular porosity type, modular and vaggy.

关键词： Zagros Gadvan Darian Cretaceous Sequence Stratigraphy

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Lithostratigraphy and Microbiostratigraphy of Gadvan and Darian Formations in South Semirom, East of Zagros Basin, South-Central Iran

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Open Journal of Geology 2017年第2期7卷 119-131页

This research focuses on the lithostratigraphy and microbiostratigraphy implications of the Gadvan and Darian Formations in a part of Zagros sedimentary basin. The Gadvan and Darian Formations in the study area with a thick-ness of 520 meters consist of gray to green marls and shales, dark-grey limestones and Orbitolina limestone with Late Barremian-Aptian age. According to the lithostratigraphic investigations, the Gadvan and Darian Formations in the study area are subdivided into eleven units. The upper boundary of the Darian Formation with the Kazhdomi Formation and the lower boundary of Gadvan Formation with the Fahliyan Formation are in the form of disconformity. Micropaleontological study of the Gadvan and Dariyan Formations has led to the recognition 20 families, 45 genera, 35 species of benthic foraminifera, 2 genera of pelagic foraminifera and 8 genera and species of the calcareous algae. In this research, three biozones have been recognized by distribution of the larger benthic foraminifera in the Gadvan and Dariyan Formations of the South Semirom, including: 1) Palorbitolina lenticularis-Choffatella decipiens Concurrent Range Zone (middle Late Barremian to early Early Aptian);2) Praeorbitolina cormyi-Orbitolina (Mesorbitolina) lotzei Assemblage Zone (late Early Aptian);3): Orbitolina (Mesorbitolina) texanae-Orbitolina (Mesorbitolina) parva Assemblage Zone (Middle to Late Aptian). Based on the identified foraminifera, the age of the Gadvan and Darian Formations in the study area is assigned to Late Barremian to Aptian.

关键词： Lower Cretaceous Foraminifera Gadvan Darian Biozone Zagros Semirom

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The emergence of drug resistant HIV variants and novel anti-retroviral therapy

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Asian Pacific Journal of Tropical Biomedicine 2013年第7期3卷 515-522页

作者： Koosha Paydary Parisa Khaghani Sahra Emamzadeh-Fard seyed Ahmad seyed Alinaghi kazem Baesi Iranian Research Center for HIV/AIDS (IRCHA) Iranian Institute for Reduction of High-Risk Behaviors Tehran University of Medical SciencesTehran Iran Students'Scientific Research Center Tehran University of Medical SciencesTehran Iran

After its identification in 1980s,HIV has infected more than 30 million people *** era of highly active anti-retroviral therapy,anti-retroviral drug resistance results frominsufficient anti-retroviral pressure,which may lead to treatment *** studiessupport the idea that anti-retroviral drug resistance has evolved largely as a result of low-adherence of patients to therapy and extensive use of anti-retroviral drugs in the developedworld;however,a highly heterogeneous horde of viral quasi-species are currently circulating indeveloping ***,the prioritizing of strategies adopted in such two worlds should be quitedifferent considering the varying anti-retroviral drug resistance *** this article,weexplore differences in anti-retroviral drug resistance patterns between developed and developingcountries,as they represent two distinct ecological niches of HIV from an evolutionary standpoint.

关键词： HIV infection Evolution,Drug resistance Developed world Developing world

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