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Cooperative Communication with Asymmetric Channel State Information: A Contract Theoretic Modeling Approach

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China Communications 2013年第1期10卷 31-43页

作者： Bahareh nazari Abbas Jamalipour School of Electrical and Information Engineering The University of Sydney

In relay-assisted cooperative communication,relay nodes help forwarding the information of a source node in case of link failure between the source and a *** user cooperation improves the overall efficiency of the network,it requires incentive to stimulate potential relay nodes to assist the source by forwarding its data to the ***,the potential relays are better informed than the source about their channel conditions to destination,which results in asymmetric information between the source and the *** this paper,we study the problem of lack of forwarding incentive in cooperative communication when channel state information of relays is private information and not known by the *** tackle this problem,we apply the principle of contract theory to a cooperative wireless *** first designs incentive compatible and individually rational contract,consisting of a set of power-credit *** it broadcasts contract items to nearby *** the source node receives reply messages from the volunteer relays,it chooses one or more relays based on its requirements and communication *** results show how credit assignment works in order to stimulate relays to cooperate and prevents relays from cheating behavior.

关键词： cooperative communication co- operative relay mobile telecommunications

Determination of Trace Amounts of Lead by Modified Graphite Furnace Atomic Absorption Spectrometry after Liquid Phase Microextraction with Pyrimidine-2-thiol

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American Journal of Analytical Chemistry 2011年第7期2卷 757-767页

作者： Saeid nazari 不详

The liquid phase microextraction (LPME) was combined with the modified Graphite furnace atomic absorption spectrometry (GF-AAS) for determination of lead in the water and solid samples. In a preconcentration step, lead was extracted from a 2 ml of its aqueous sample in the pH = 5 as lead-Pyrimidine-2-thiol cationic complex into a 4 μl drop of 1,2 dichloroethane and ammonium tetraphenylborate as counter ion immersed in the solution. In the drop, the lead-Pyrimidine-2-thiol ammonium tetraphenylborate ion associated complex was formed. After extraction, the microdrop was retracted and directly transferred into a graphite tube modified by [***] (c). Some effective parameters on extraction and complex formation, such as type and volume of organic solvent, pH, concentration of chelating agent and counter ion, extraction time, stirring rate and effect of salt were optimized. Under the optimum conditions, the enrichment factor and recovery were 525% and 94%, respectively. The calibration graph was linear in the range of 0.01 - 12 μg?L–1 with correlation coefficient of 0.9975 under the optimum conditions of the recommended procedure. The detection limit based on the 3Sb criterion was 0.0072 μg?L–1 and relative standard deviation (RSD) for ten replicate measurement of 0.1 μg?L–1 and 0.4 μg?L–1 lead was 4.5% and 3.8% respectively. The characteristic concentration was 0.0065 μg?L–1 equivalent to a characteristic mass of 26 fg. The results for determination of lead in reference materials, spiked tap water and seawater demonstrated the accuracy, recovery and applicability of the presented method.

关键词： Lead Liquid Phase Microextraction Preconcentration Graphite Furnace Atomic Absorption Spectrometry

Distribution changes of woody plants in Western Iran as monitored by remote sensing and geographical information system:a case study of Zagros forest

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Journal of Forestry Research 2017年第1期28卷 145-153页

作者： Mansour Karkon Varnosfaderani Rasoul Kharazmi Aliakbar nazari Samani Mohammad Reza Rahdari Seid Hamid Matinkhah Nasrollah Aslinezhad State University of Land Use Planning MoscowRussianFederation St.Petersburg State University PetersburgRussianFederation Faculty of Natural Resource University of TehranKarajIran Isfahan University of Technology IsfahanIran Faculty of Water and Soil Zabol UniversityZabolIran

The status of woody plants in dry-land systems is a fundamental determinant of key ecosystem processes. Monitoring of this status plays an important role in understanding the dynamics of woody plants in arid and semi-arid ecosystems. The present study determined the dynamism of the Zagros forests in Iran using Remote Sensing and Geographic Information System techniques and statistical science. The results show that the density of trees varied from 10 to 53 % according to the physio- graphic and climatic conditions of semi-arid regions. The best and lowest correlation between vegetation indices and forest density were obtained for the global environmental monitoring index （GEMI; R2 = 0.94） and soil adjust vegetation index （R2 = 0.81）, respectively. GEMI is used to monitor land use changes over a 10-year period. Results show that 2720 ha2 of forest have been destroyed by human interference and tillage on steep slopes during this period which also resulted in the loss of the fertile soil layer. GEMI determined the areas with a biomass of trees and could normally separate border regions with low bio- mass density of trees from regions without canopy cover. The results revealed that assessment of forest and vegetation cover in arid and semi-arid arduous forest regions using satellite digital numbers and ordinary sampling is subject to uncertainty. A stratified grouping procedure should be established to increase the accuracy of assessment.

关键词： Monitoring Woody plants Vegetation index RS GIS Zagros forest Iran

Lattice Boltzmann simulation of double diffusive natural convection in a square cavity with a hot square obstacle

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Chinese Journal of Chemical Engineering 2015年第1期23卷 22-30页

作者： Mohsen nazari Ladan Louhghalam Mohamad Hassan Kayhani Department of Mechanical Engineering University of Shahrood

Double diffusion convection in a cavity with a hot square obstacle inside is simulated using the lattice Boltzmann method. The results are presented for the Rayleigh numbers 104,105 and 106, the Lewis numbers 0.1, 2 and 10 and aspect ratio A(obstacle height/cavity height) of 0.2, 0.4 and 0.6 for a range of buoyancy number N = 0 to- 4 with the effect of opposing flow. The results indicate that for |N| b 1, the Nusselt and Sherwood numbers decrease as buoyancy ratio increases, while for |N| N 1, they increase with |N|. As the Lewis number increases, higher buoyancy ratio is required to overcome the thermal effects and the minimum value of the Nusselt and Sherwood numbers occur at higher buoyancy ratios. The increase in the Rayleigh or Lewis number results in the formation of the multi-cell flow in the enclosure and the vortices will vanish as |N| increases.

关键词： Lattice Boltzmann method Double diffusion Hot obstacle Opposing buoyancy force

Evidence-based practice profiles of nurses: a transcultural study

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Frontiers of Nursing 2022年第1期9卷 29-35页

作者： Reza Negarandeh Rajab nazari Frank Kiwanuka Waliu Jawaula Salisu Shah Jahan Shayan Nursing and Midwifery Care Research Center School of Nursing and MidwiferyTehran University of Medical SciencesTehranTehran ***Iran Department of Fundamental of Nursing School of Nursing and MidwiferyKabul University of Medical SciencesKabulKabul 1006Afghanistan School of Nursing and Midwifery Tehran University of Medical SciencesInternational CampusTehranTehran ***Iran

Objective: To compare(i) the evidence-based practice(EBP) profiles and(ii) socio-demographic characteristics of nurses in 4 selected low-middle income countries(LMICs).Methods: A cross-sectional survey was conducted among 677 nurses from 4 hospitals in 4 countries(Afghanistan, Ghana, Iran, and Uganda).Results: The findings revealed that there are significant differences between the 3 EBP subscales(that is, practice/use, attitude, and knowledge/skill) across the 4 countries(P < 0.05). No significant EBP differences were identified across age groups and gender in the subscales of practice, knowledge, and attitude. Practice and knowledge subscales were significantly associated with working schedules(that is, par t-time and full-time)(P < 0.05). Analyses also revealed significant differences between attitude and knowledge subscales and working experience(P < 0.05).Conclusions: Nurses in the 4 countries have moderate practice, attitude, and knowledge/skil s of EBP. Nurses in LMICs require continuous professional development programs and suppor t to enhance their practice and knowledge regarding EBP in clinical settings.

关键词： evidence-based practice nursing transcultural

Anticancer effect of Psidium guajava(Guava) leaf extracts against colorectal cancer through inhibition of angiogenesis

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Asian Pacific Journal of Tropical Biomedicine 2020年第7期10卷 293-307页

作者： Bronwyn Lok Doblin Sandai Hussein M.Baharetha Mansoureh nazari V Muhammad Asif Chu Shan Tan AMS Abdul Majid EMAN Laboratory Discipline of PharmacologySchool of Pharmaceutical SciencesUniversiti Sains MalaysiaPenangMalaysia Infectomics Cluster Advance Medical and Dental InstituteUniversiti Sains MalaysiaPenangMalaysia Department of Pharmacy College of Medicine and Health SciencesHadhramout UniversityHadhramoutYemen Department of Pharmacology Faculty of Pharmaceutical SciencesGovernment College University FaisalabadFaisalabadPakistan Discipline of Pharmacology School of Pharmaceutical SciencesUniversiti Sains MalaysiaPenangMalaysia ACRF Department of Cancer Biology and Therapeutics John Curtin School of Medical ResearchAustralian National UniversityCanberraAustralia

Objective:To evaluate the anti-angiogenic and anticancer activities of Psidium guajava leaf extracts against angiogenesis-dependent colorectal ***:Three extracts were produced using distilled water,ethanol,and n-hexane as *** extracts were physically characterised through gas chromatography–mass spectrometry,ultraviolet–visible spectroscopy,and Fourier transform infrared *** antioxidant activity was evaluated using the 2,2-diphenyl-1-picrylhydrazyl,total phenolic content,and total flavonoid content *** assess their anti-angiogenic activity,cell viability and rat aortic ring assays were conducted,while cell migration,tube formation,colony formation,and VEGF ELISA assays were conducted to elucidate their effects on different aspects of *** docking was used to assess the antiangiogenic potential of some possible compounds in the *** spheroid assay was used to assess the extracts’potential as a treatment for colorectal ***:The ethanol extract showed the best antioxidant *** distilled water and ethanol extracts exhibited more inhibitory activity against ***926 cell viability and aortic ring microvessel *** addition,the ethanol extract performed significantly better than the distilled water extract against cell migration and colony formation,and VEGF expression of the cells was suppressed by the ethanol *** the distilled water and ethanol extracts showed significant inhibitory effect on ***926 tube formation and tumour spheroids consisting of ***926 and HCT116 *** ethanol extract containedβ-caryophyllene andβ-elemene by phytochemical analysis and subsequent docking studies,which may contribute to its anti-angiogenic ***:The ethanol extract of Psidium guajava has potential in the treatment of colorectal cancer through the inhibition of angiogenesis.

关键词： Angiogenesis Antioxidant Colorectal cancer Psidium guajava VEGF

Epidemiological Pattern of Scabies and Its Social Determinant Factors in West of Iran

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Health 2014年第15期6卷 1972-1977页

作者： Mansour nazari Aziz Azizi Department of Medical Entomology School of Medicine Hamadan University of Medical Sciences Hamadan Iran

Objectives: Scabies has a different epidemiological distribution among different communities worldwide due to different social factors, management approaches and healthcare policies. The present study came to address outbreaks of scabies according to the social factors in west of Iran. Methods: In a cross-sectional study, using the census sampling method, all consecutive patients with the primary diagnosis of scabies based on clinical manifestations referred to healthcare center throughout the two great provinces of Hamadan and Kermanshah at western Iran between March 2006 and February 2010 were enrolled into the study. The baseline characteristics were collected from recorded files at the healthcare centers or by interviewing with the affected patients. Results: Among 3,625,966 subjects covered by the two studied provinces, 177 cases of scabies (170 cases in Kermanshah and 7 cases in Hamadan) were identified by medical staff at the healthcare centers according to clinical manifestations (85.3%) and laboratory microscopic assessments (14.7%). The highest and the lowest prevalence rates were specified to 2009 (58.2%) and 2008 (1.7%). Regarding gender distribution of disease, 53.1% of men and 46.9% of women suffered from scabies with no significant discrepancy. In respect to age distribution of disease, the highest rates of scabies were revealed in the ages ranged 17 to 30 years (31.6%), followed by younger than 17 years (30.5%). The prevalence of scabies was dependently associated with residency in rural areas, family history of scabies, lower educational level, household density, lower monthly income, low personal hygiene, the existence of livestock or rodents at home, seasonal conditions, and movement to contaminated areas. Conclusion: West region of Iran especially Kermanshah province faced with high prevalence and this high disease burden can be determined by some potential factors such as residency in rural areas, family history of scabies, lower educational lev

关键词： Scabies Sarcoptes Scabiei Pruritus Epidemiology Iran

Vaginitis in Intrauterine Contraceptive Device Users

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Health 2014年第11期6卷 1218-1223页

作者： Fatemeh Shobeiri Mansour nazari Department of Medical Entomology School of Medicine Hamadan University of Medical Sciences Hamadan Iran Research Center for Child & Maternity Care (RCCMC) Hamadan University of Medical Sciences Hamadan Iran

Objectives: This study aimed to assess clinical, microbial changes in IUD users and other contraceptive methods in referent to urban health centers in Hamadan city, Iran. Methods: Detailed history and gynecological examination were conducted on women (IUD users, n = 100) or other contraceptive methods (controls, n = 160) in the health centers. Results: Frequencies of the different vaginal pathogens, high indices of infection by bacterial vaginosis (12.0%) candida albicance (7.0%) and low indices of trichomoniasis (5.0%) were found in present study, but none of them in both groups was significant. Menorrhagia was more frequent among women with IUD than that among women without IUD (P < 0.05). A trend of erosion cervix and dysmenorrhea being more frequent among women with IUD was also found (P < 0.05). Conclusions: IUD is the safety in general;however, an increase occurred in the frequency of vaginitis.

关键词： Intrauterine Device Vaginitis Microbial Agent Erosion Cervix

TOXIC EFFECT OF AMITRIPTYLINE ON THE FECUNDITY,FERTILITY AND VIABILITY OF DROSOPHILA MELANOGASTER BY ADULT FEEDING

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TOXIC EFFECT OF AMITRIPTYLINE ON THE FECUNDITY,FERTILITY AND...