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Comparison of exogenous melatonin versus placebo on sleep efficiency in emergency medicine residents working night shifts： A randomized trial

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World Journal of Emergency Medicine 2018年第4期9卷 282-287页

作者： Shcrvin Farahmand Masoume Vafaeian Elnaz Vahidi atefeh abdollahi Shahram Baghcri-Hariri Ahmad Reza Dehpour Emergency Medicine Department Imam Khomeini Hospital Tehran University of Medical Sciences Tehran Iran Emergency Medicine Department Shariati Hospital Tehran University of Medical Sciences Tehran Iran Emergency Medicine Department Sina Hospital Tehran University of Medical Sciences Tehran Iran Department of Pharmacology Tehran University of Medical Sciences Tehran Iran

BACKGROUND: Sleep deprivation resulting from night shifts, is a major cause of burnout among physicians. Exogenous melatonin may improve sleep quality in night-shift workers. The study aims to compare the effectiveness of melatonin versus placebo on sleep effi ciency in emergency medicine(EM) residents. METHODS: A randomized, double-blind, replicated crossover trial was performed on EM residents. This study consisted of 4 phases within a month with intervention periods of 2 nights and washouts of 6 days. In our study, EM residents had nine-hour shifts on 6 consecutive days, 2 mornings, 2 evenings and 2 nights and then 2 days off. At the end of shifts' cycle, 24 EM residents were given 3 mg melatonin or placebo(12 in each arm of the study) for 2 consecutive nights after the second night shift with crossover to the other arm after a six-day off drug. This crossover intervention was repeated for two more another time. Finally, we created 48 cases and comparisons in each arm. Different items related to sleep quality were assessed and compared both within the same group and between the two groups. RESULTS: In the melatonin group, daytime sleepiness(calculated by Karolinska Sleep Scale) had a signifi cant reduction after taking the second dose of drug(P=0.003) but the same result was not observed when comparing the 2 groups. Mood status(calculated by Profile of Mood States) showed no remarkable difference between the 2 groups. CONCLUSION: Melatonin might have a limited benefi t on sleep quality in EM residents working night shifts.

关键词： Melatonin Placebo Emergency medicine Night shift Sleep

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MOS structure fabrication by thermal oxidation of multilayer metal thin films

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Journal of Semiconductors 2011年第3期32卷 135-139页

作者： Mohammad Orvatinia atefeh Chahkoutahi Electron Engineering Department Information and Communication Technology(ICT) FacultyICT Ministry of Iran Bushehr Azad University

A novel approach for the fabrication of a metal oxide semiconductor（MOS） structure was *** process comprises electrochemical deposition of aluminum and zinc layers on a base of nickel-chromium alloy. This two-layer structure was thermally oxidized at 400℃for 40 min to produce thin layers of aluminum oxide as an insulator and zinc oxide as a semiconductor on a metallic *** deposition parameters,device dimensions and SEM micrographs of the layers,the device parameters were *** resultant MOS structure was characterized by a C-V curve *** this curve,the device maximum capacitance and threshold voltage were estimated to be about 0.74 nF and -2.9 V,respectively,which are in the order of model-based calculations.

关键词： MOS structure electrochemical deposition thermal oxidation C-V curve

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From furnace up to freezer:Elevational patterns of plant diversity in Mount Palvar,a semi-arid Irano-Turanian mountain range of southwest Asia

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Journal of Mountain Science 2024年第7期21卷 2236-2248页

作者： atefeh GHORBANALIZADEH Moslem DOOSTMOHAMMADI Kerman *** Iran

Much of the world's biodiversity lies in heterogeneous mountain areas with their diverse *** an example,Iranian montane ranges are highly diverse,particularly in the Irano-Turanian phytogeographical *** plant diversity patterns with increasing elevation is of high significance,not least for conservation *** studied the pattern of species richness,Shannon diversity,endemic richness,endemics ratio,and richness of life forms along a 3900 m elevational transect in Mount Palvar,overlooking the Lut Desert in Southeast *** also analyzed the effect of environmental variables on species turnover along the vertical gradient.A total of 120 vegetation plots(10 m×10 m)were sampled along the elevational transect containing species and environmental *** discover plant diversity pattern along the elevational gradient,generalized additive model(GAM)was ***-metric multidimensional scaling(NMDS)was applied for illustrating the correlation between species composition and environmental *** found hump-shaped pattern for species richness,Shannon diversity,endemic richness,and species richness of different life forms,but a monotonic increasing pattern for ratio of endemic species from low to high *** study confirms the humped pattern of species richness peaking at intermediate elevations along a complete elevational gradient in a semi-arid *** monotonic increase of endemics ratio with elevation in our area as a case study is consistent with global increase of endemism with *** to our results,temperature and precipitation are two important climatic variables that drive elevational plant diversity,particularly in seasonally dry *** study suggests that effective conservation and management are needed for this low latitude mountain area along with calling for long-term monitoring for species redistribution.

关键词： Elevational gradient Biodiversity Endemic Generalized additive model Hump-shaped pattern Irano-Turanian region

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Plant diversity of Hyrcanian relict forests:An annotated checklist,chorology and threat categories of endemic and near endemic vascular plant species

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Plant Diversity 2022年第1期44卷 39-69页

作者： atefeh Ghorbanalizadeh Hossein Akhani Halophytes and C4 Plants Research Laboratory Department of Plant SciencesSchool of BiologyCollege of SciencesUniversity of TehranP.O.Box 14155-6455TehranIran

In this paper a critical annotated checklist of 256 endemic and near endemic species belonging to 152 genera and 50 families of flowering plants known from Hyrcanian relict forests is *** maps of taxa,elevational range,number of known records,chorotypes,life forms,IUCN threat categories and habitat types are also *** chorotypes are categorized into eight main patterns:1)the Omni-Hyrcanian pattern(OH),2)West Hyrcanian pattern(WH),3)Manjil-Rudbar pattern(MR),4)Central Hyrcanian pattern(CH),5)Central and East Hyrcanian pattern(CEH),6)East Hyrcanian pattern(EH),7)Alborz-Hyrcanian pattern(AH),and 8)Euxino-Hyrcanian pattern(XH).The richness and distribution maps were generated based on 5408 records gained from herbarium specimens and literature *** life form spectra show that the majority of taxa(54.7%)belong to hemicryptophytes,followed by the tuberous,bulbous and parasitic geophytes with 45 species(17.6%)and phanerophytes with 28 taxa(10.9%).The conservation status of species according to IUCN criteria indicates that 30 taxa are Critically Endangered,52 taxa Endangered,30 taxa Vulnerable,25 taxa Near Threatened and 81 taxa are of Least *** present data were not sufficient to evaluate 38 taxa that are categorized here as Data *** new combination of Leutea translucens(=Peucedanum translucens)is validated with inclusion of Peucedanum hyrcanicum as its *** disjunct occurrence of the Caucasian species Gentiana grossheimii is reported from the eastern parts of the Hyrcanian forests in Iran for the first *** conclude that(i)the Hyrcanian forests and associated habitats in the northern slopes of the Alborz Mountains harbour tremendous floristic diversity of high conservation priority,and(ii)the Hyrcanian forest zone is an important and unique center of endemism within the Euro-Siberian region that should be considered a floristic province with a large number of relict species.

关键词： Biodiversity Distribution pattern Endemic plant Hyrcanian forests IUCN category

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Application of consistent geometric decomposition theorem to dynamic finite element of 3D composite beam based on experimental and numerical analyses

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 675-689页

作者： Iman FATTAHI Hamid Reza MIRDAMADI Hamid abdollahi Department of Mechanical Engineering Isfahan University of TechnologyIsfahan ***Iran

Analyzing static and dynamic problems including composite structures has been of high significance in research efforts and industrial *** this article,equivalent single layer approach is utilized for dynamic finite element procedures of 3D composite beam as the building block of numerous composite *** this model,both displacement and strain fields are decomposed into cross-sectional and longitudinal components,called consistent geometric decomposition ***,the model is discretized using finite clement *** local coordinate systems and a global one are defined to decouple mechanical degrees of ***,from the viewpoint of consistent geometric decomposition theorem,the transformation and element mass matrices for those systems are introduced here for the first *** same decomposition idea can be used for developing element stiffiness ***,comprehensive validations are conducted for the theory against experimental and numerical results in two case studies and for various conditions.

关键词： composite beam dynamic finite element degrees of freedom coupling experimental validation numerical validation

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Changes in soil organic carbon,nitrogen and sulphur along a slope gradient in apple orchard soils of Kashmir Himalaya

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Journal of Mountain Science 2021年第9期18卷 2377-2387页

作者： Javaid M DAD Lotfollah abdollahi Department of Botany University of KashmirHazratbalSrinagar(J&K)India Faculty of Agriculture Payame Noor UniversityTehranP.O.Box 19395-3697Iran

Accumulation and losses of soil organic carbon(SOC),total nitrogen(TN)and sulphur(S)influence food security and global ***,their spatial distribution and variability at regional scale,and their relation to topographical variables are of great *** this study,the variability of SOC,TN and S content was evaluated in apple orchard soils of Kashmir region,at three depths(D1:0-10,D2:10-20,and D3:20-30 cm)on slope gradient i.e.:flat,medium,and *** an increase in slope,a significant decrease of SOC and TN was observed,with concentration of SOC and TN recorded highest(14.3±2.06 g kg-1&0.97±0.35 g kg-1)in flat slope orchards and lowest(9.6±2.07 g kg-1&0.84±0.41 g kg-1)in high slope *** stock basis,the values recorded for flat,medium,and high slope orchards,for SOC and TN were 54.62±4.24 Mg ha-1&0.38±0.06 Mg ha-1,44.13±5.11 Mg ha-1&0.32±0.09 Mg ha-1,and 38.73±5.94 Mg ha-1&0.28±0.10,*** differences for S concentration and stocks were modest,with flat(0.21±0.15 mg kg-1&0.09±0.0.003 Mg ha-1)>high(0.16±0.07 mg kg-1&0.06±0.007 Mg ha-1)>medium(0.12±0.04 mg kg-1&0.075±0.009 Mg ha-1).Across slopes,SOC,TN and S decreased with increasing soil depth,suggesting clear downward ***,SOC and TN increased with the increase of altitude,precipitation and clay content while its relationship with soil acidity and soil bulk density was *** findings may provide scientific basis to structure agricultural development plans or prioritize regions for soil conservation efforts.

关键词： Apple orchards Slope Soil organic carbon Sulphur Total nitrogen Soil bulk density

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Fault detection of new and aged lithium-ion battery cells in electric vehicles

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Green Energy and Intelligent Transportation 2024年第3期3卷 42-53页

作者： Sara Sepasiahooyi Farzaneh abdollahi Department of Electrical Engineering Amirkabir University of Technology(Tehran Polytechnic)424 Hafez AveTehranIran Department of Mechanical Engineering Texas Tech UniversityLubbockTXUSA Department of Mechanical and Aerospace Engineering Carleton UniversityOttawaONCanada

In this paper,a novel model-based fault detection in the battery management system of an electric vehicle is *** adaptive observers are designed to detect state-of-charge faults and voltage sensor faults,considering the impact of battery *** aging primarily affects capacity and resistance,becoming more pronounced in the later stages of a battery *** incorporating aging effects into our fault diagnosis scheme,our proposed approach prevents false or missed alarms for the aged battery *** aging effect of battery,capacity fading and resistance growth,are considered unknown *** adaptive observer is employed to design a fault detector,considering unknown parameters in the battery *** adaptive observers are designed for two different scenarios:In the first scenario,it is presumed that aging effects remain constant over time due to their slow rate of ***,it is assumed that aging effects are ***,the fault detection scheme can detect faults of new battery cells as well as aged *** simulations have been conducted on a Lithium-ion battery cell and extended to battery pack,to demonstrate the performance of the proposed approach in more real-world *** results showed that the designed observers can detect faults correctly in a seven years old battery as well as a new one.

关键词： Adaptive observer Aging Electric vehicle Fault detection Lithium-ion battery State of charge

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Phototriggered structures:Latest advances in biomedical applications

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Acta Pharmaceutica Sinica B 2023年第7期13卷 2844-2876页

作者： Mojtaba Shamsipur atefeh Ghavidast Afshin Pashabadi Department of Chemistry Razi UniversityKermanshah ***Iran

Non-invasive control of the drug molecules accessibility is a key issue in improving diagnostic and therapeutic *** studies have explored the spatiotemporal control by light as a peripheral *** drug delivery systems(PTDDSs) have received interest in the past decade among biological researchers due to their capability the control drug *** this end,a wide range of phototrigger molecular structures participated in the DDSs to serve additional efficiency and a high-conversion release of active fragments under light *** to now,several categories of PTDDSs have been extended to upgrade the performance of controlled delivery of therapeutic agents based on well-known phototrigger molecular structures like o-nitrobenzyl,coumarinyl,anthracenyl,quinolinyl,o-hydroxycinnamate and hydroxyphenacyl,where either of one endows an exclusive feature and distinct mechanistic *** review conveys the design,photochemical properties and essential mechanism of the most important phototriggered structures for the release of single and dual(similar or different) active molecules that have the ability to quickly reason of the large variety of dynamic biological phenomena for biomedical applications like photo-regulated drug release,synergistic outcomes,real-time monitoring,and biocompatibility potential.

关键词： Phototrigger Light irradiation Excited state proton transfer Drug delivery system Dynamic process Controlling chemistry

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Using an Inhibitor to Prevent Plasticizer Migration from Polyurethane Matrix to EPDM Based Substrate

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Chinese Journal of Polymer Science 2019年第7期37卷 681-686页

作者： Hadi Rezaei-Vahidian Tohid Farajpour Mahdi abdollahi Space Transportation Research Institute Iranian Space Research CenterTehranIran Polymer Reaction Engineering Department Faculty of Chemical EngineeringTarbiat Modares UniversityTehranIran

The loss of adhesion between the propellant and insulator is one of the most important problems in solid propellant motors due to migration of plasticizer to interface of propellant and insulator. In this work, the polyurethane (PU) binder containing DOP plasticizer was used as a polymeric matrix and β-cyclodextrin (β-CD) was applied as inhibitor agent to prevent plasticizer migration from the PU matrix into the ethylene propylene diene monomer (EPDM) substrate. To increase the compatibility of β-CD and PU matrix, a derivative of β-CD has been synthesized using toluene diisocyanate (β-CD-TDI). The synthesized derivative was characterized by MALDI-MS and FTIR-ATR analyses. FTIR-ATR results confirmed the formation of bonding between β-CD and the polymeric network while the MALDIMS results showed that the synthesized derivative contained two β-CD and 7 TDI molecules bonded to β-CD. Investigation of the mechanical properties of PU modified by β-CD-TDI showed a decrease in tensile strength and an increase in elongation at break with increasing β-CD-TDI content. DMTA results showed a decrement in crosslinking density by increasing the β-CD-TDI content. Also, to investigate plasticizer migration, extraction of the DOP plasticizer from samples was performed using dichloromethane solvent and its concentration was measured by gas chromatography. The results of migration evaluation after four months showed that using β-CD as an inhibitor agent in the PU binder could prevent the migration of plasticizer to EPDM substrate.

关键词： Plasticizer migration β-Cyclodextrin Polyurethane

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Experimental investigation and development of new correlation for influences of temperature and concentration on dynamic viscosity of MWCNT-SiO2(20-80)/20W50 hybrid nano-lubricant

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Chinese Journal of Chemical Engineering 2018年第1期26卷 152-158页

作者： Kazem Motahari Mohammad abdollahi Moghaddam Mojtaba Moradian Department of Chemical Engineering Faculty of EngineeringArak UniversityArak 38156-8-8349Iron Young Researchers and Elite Club Malayer BranchIslamic Azad UniversityMalayerIran

In current research, MWCNT-SiO2/oil hybrid nano-lubricant viscosity is experimentally examined. By dispersing 0.05%, 0.1%, 0.2%, 0.4%, 0.8% and 1% volume of MWCNTs and SiO2 nanopartide into the engine oil SAE 20W50, the temperature and solid volume fraction consequences were studied. At 40 to 100 ℃ temperature, the viscosities were assessed. The results indicated Newtonian behavior for the hybrid nano-lubricant. Moreover, solid volume fraction augmentation and temperature enhanced the viscosity enhancement of hybrid nano-lubricant. At highest solid volume fraction and temperature, nano-lubricant viscosity was 171% greater compared to pure 20W50. Existed models lack the ability to predict the hybrid nano-lubricant viscosity. Thus, a new correlation regarding solid volume fraction and temperature was suggested with R-squared of 0.9943.

关键词： Hybrid nano-lubricant Dynamic viscosity Temperature Solid volume fraction New correlation

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