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2.
Nature ; 577(7790): 318, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31937965
3.
Arch Virol ; 165(1): 185-192, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31637514

RESUMEN

Cucumber mosaic virus (CMV) is a geographically widespread plant virus with a very broad host range. The virus has been detected in diverse crops all over Iran. In this study, we estimated the timescale of the evolution of CMV subgroup I and the geographical movement of the virus with a focus on Iranian strains. Analyses using the MP and CP genes and their concatenation revealed that the CMV population within subgroup I had a single ancestor dating back to about 450-550 years ago. The Iranian strains formed three clusters in a maximum-clade-credibility phylogenetic tree. It was found that the most recent common ancestor of the Iranian strains within each cluster dates back to less than 100 years ago. Our results also suggest that both short- and long-distance migration of Iranian CMV strains has occurred in the last 100 years.


Asunto(s)
Cucumovirus/clasificación , Análisis de Secuencia de ARN/métodos , Proteínas de la Cápside/genética , Cucumovirus/genética , Evolución Molecular , Irán , Filogenia , Proteínas Virales/genética
4.
J Sci Food Agric ; 100(3): 1048-1055, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31677164

RESUMEN

BACKGROUND: Magnetic three-dimensional graphene-based nanoadsorbents have unique characteristics such as large surface area, good thermal and chemical stability, and high adsorption capacity that make them efficient materials in sorbent-based extraction techniques. In this study, four aflatoxins (AFs) were analyzed in bread samples using magnetic three-dimensional graphene as the adsorbent phase in dispersive micro solid-phase extraction. RESULTS AND CONCLUSIONS: In-syringe magnetic sheet solid-phase extraction based on magnetic three-dimensional graphene in tandem with dispersive liquid-liquid microextraction was used for the extraction and preconcentration of the target AFs. The effect of significant parameters of the method was investigated and the optimum conditions were determined as follows: adsorbent dosage, 20 mg; desorption/disperser solvent (methanol) volume, 700 µL; desorption solvent flow rate, 0.7 mL min-1 ; pH, neutral; salt (NaCl) concentration, 10% (w/v); extraction solvent (chloroform) volume, 250 µL; and centrifugation rate (and time), 4000 rpm (5 min). The limits of detection and quantification were in the ranges 0.043-0.083 and 0.14-0.28 µg kg-1 , respectively. The extraction method was followed by the HPLC technique with fluorescence detection and applied to the determination of the AFs in four different Iranian fresh and moldy bread samples. The relative recoveries were in the range 84-107% with relative standard deviations of 3.9-8.6%. © 2019 Society of Chemical Industry.


Asunto(s)
Aflatoxinas/aislamiento & purificación , Pan/análisis , Contaminación de Alimentos/análisis , Microextracción en Fase Líquida/métodos , Magnetismo/métodos , Extracción en Fase Sólida/métodos , Adsorción , Aflatoxinas/análisis , Cromatografía Líquida de Alta Presión , Irán , Extracción en Fase Sólida/instrumentación , Jeringas
5.
Arch Virol ; 165(1): 115-125, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31741096

RESUMEN

The latest class of antiretrovirals (ARVs), including integrase strand transfer inhibitors (INSTIs), has been demonstrated to be effective for antiretroviral therapy (ART). Despite all the distinguishing characteristics of these drugs, including a high genetic barrier to resistance and lower toxicity than other ARVs, unfortunately, INSTI drug resistance mutations (DRMs) have occasionally been observed. The aim of this study was to investigate the presence of DRMs associated with INSTIs among treatment-experienced HIV-1-infected patients. From June 2012 to December 2018, a total of 655 treatment-experienced HIV-1-infected patients enrolled in this cross-sectional survey. Following amplification and sequencing of the HIV-1 integrase region of the pol gene, DRM and phylogenetic analysis were successfully carried out on the plasma samples of patients who had a viral load over 1,000 IU/ml after at least 6 months of ART. Out of the 655 patients evaluated, 62 (9.5%) had a viral load higher than 1,000 IU/ml after at least 6 months of ART. Phylogenetic analysis showed that all of the 62 HIV-1 patients experiencing treatment failure were infected with CRF35_AD, and one of these patients (1.6%) was infected with HIV-1 variants with DRMs. The DRMs that were identified belonged to the INSTI class, including E138K, G140A, S147G, and Q148R. This survey shows that DRMs belonging to the INSTI class were detected in an Iranian HIV patient who has experienced treatment failure. Therefore, regarding the presence of DRMs to INSTIs in ART-experienced patients, it seems better to perform drug resistance mutation testing in HIV patients experiencing treatment failure before changing the ART regimen and prescribing this class of medication.


Asunto(s)
Farmacorresistencia Viral , Infecciones por VIH/virología , Integrasa de VIH/genética , VIH-1/clasificación , Mutación , Adolescente , Adulto , Anciano , Niño , Preescolar , Estudios Transversales , Femenino , Infecciones por VIH/tratamiento farmacológico , VIH-1/enzimología , VIH-1/genética , Humanos , Lactante , Irán , Masculino , Persona de Mediana Edad , Filogenia , Análisis de Secuencia de ARN , Adulto Joven
6.
Waste Manag Res ; 38(1): 44-58, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31438782

RESUMEN

The main objective of this research was to investigate the waste characteristics and management activities in the Savojbolagh industrial zone, Iran, in order to rank the active industries from environmental perspectives using an innovative index. First, the industrial categories with over 50 employees were identified and classified according to their production process. Then, 54 industries were selected and all industrial processes, the types and quantities of products, per capita industrial waste generation, physical analysis and management activities in terms of minimisation, storage, processing, recycling and disposal were evaluated. The required data were obtained through questioners, interviews and field observations. A scoring system was prepared for evaluation of environmental status of waste management practices. Results indicated that the total industrial waste generation rate was 67,258 kg d-1, in which 4528 belonged to hazardous waste. Furthermore, the per capita waste generation rate was 5.51 kg d-1. Plastic, paper and cardboard and metals constituted the most fractions of wastes, respectively. Food and beverage, metallic and chemical/plastic industries were the biggest waste generators. Metallic industries with total score of 502.5 and non-metalic-mineral industries with the total score of 114 were categorised as the best and worst industries in terms of waste management practices.


Asunto(s)
Residuos Industriales , Administración de Residuos , Residuos Peligrosos , Irán , Reciclaje
7.
Int J Biometeorol ; 64(1): 29-37, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31471662

RESUMEN

This investigation is an endeavor to propose an innovative indicator in order to eliminate the restrictions of similar indices. The Outdoor Tourism Climate Index (OTCI) elucidates whether or not the combination of different climatic elements, their compatibility with the climate at the travel origin, and the tourist's purpose of traveling is desirable for outdoor tourists, nature-based tourists, and the other tourists who undertake some activities in the open areas. OTCI was calculated for the outdoor tourists traveling from three different travel origins in Iran, including Tabriz, Shiraz, and Bandar Lengeh, to Bandar Abbas. The findings illuminated further accuracy and closeness to the reality of OTCI rather than Tourism Climate Index (TCI). Furthermore, as far as traveling to Bandar Abbas was concerned, the OTCI score of tourists from Bandar Lengeh (with similar climatic conditions to those at Bandar Abbas) was recognized to be higher than those from Shiraz and Tabriz (with more different climatic conditions).


Asunto(s)
Clima , Viaje , Irán
8.
Gene ; 723: 144133, 2020 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-31589956

RESUMEN

BACKGROUND AND AIM: Autism spectrum disorder (ASD) is one of the neurodevelopmental and cognitive conditions that involves 1 in 160 children around the world. Several studies showed that there is a relationship between vitamin D receptor (VDR) gene polymorphisms with the neurodevelopmental behavioral disorders. In the current study, we aimed to highlight the association of VDR gene polymorphisms (FokI and TaqI) with the risk of autism in Birjand population. MATERIAL AND METHODS: In this case-control study eighty-one patients recognized with ASD and one hundred-eight healthy controls were recruited to the study from 2017 to 2018. Genotyping was carried out by polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) technique for all subjects. RESULTS: Calculated odds ratio and P-value for the alleles of VDR gene FokI and TaqI variants between autistic patients and controls did not show a significant difference (P > 0.05). However, calculated homozygous recessive (tt) for TaqI polymorphism was statistically significant (P = 0.015) in control group and there was also statistically meaningful difference in both case and control groups in ft haplotype (P = 0.04). CONCLUSION: These results provide preliminary evidence that genetic variants of the VDR gene (FokI and TaqI) might have a possible reduced risk of ASD occurrence in children. The additional examination is needed to acquire more decisive and precise results in this area.


Asunto(s)
Trastorno del Espectro Autista/genética , Polimorfismo de Longitud del Fragmento de Restricción , Receptores de Calcitriol/genética , Adolescente , Trastorno del Espectro Autista/sangre , Estudios de Casos y Controles , Niño , Preescolar , Colecalciferol/sangre , Femenino , Estudios de Asociación Genética , Pruebas Genéticas , Humanos , Irán , Masculino
9.
Gene ; 724: 144153, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31610221

RESUMEN

As heroin and morphine produce reactive oxygen species and down-regulate several genes involved in cellular detoxification and DNA repair pathways, neurons experience DNA damage. Xeroderma pigmentosum complementation group C (XPC, OMIM: 613208) gene, which is expressed in the brain, is one of the central genes in the nucleotide excision repair pathway. Three common XPC polymorphisms (Lys939Gln, Ala499Val and PAT) are associated with reduced DNA repair capacity. In this study, the relationship between these polymorphisms and the risk of heroin dependency (HD), as well as, age of first use (AFU) for illegal drugs was investigated on 795 healthy individuals and 442 heroin dependent patients. Statistical analyses indicated that there was no significant association between the XPC polymorphisms and the risk of HD. The haplotypic frequencies of the polymorphisms showed significant difference between HD patients and healthy controls (χ2 = 16.38, df = 6, P = 0.012). Analysis indicated that the "Ala + Gln" haplotype increased the HD risk more than the "Ala + Lys" haplotype (OR = 4.21, 95% CI = 1.29-13.7, P = 0.017). In Cox proportional model, there was significant association between AFU and the Ala499Val polymorphism (Hazard ratio = 1.53, 95% CI: 1.02-2.92, P = 0.036). To investigate the effect of the linkage between the polymorphic sites, we compared the AFU among two common diplotypes ("Ala - Lys/Ala - Lys" and "Val - Lys/Val - Lys"). Statistical analysis indicated that AFU was significantly lower in "Val - Lys/Val - Lys" diplotype (t = 2.63, df = 49, P = 0.011). The present findings suggest that the XPC is a candidate polymorphic locus for AFU.


Asunto(s)
Proteínas de Unión al ADN/genética , Dependencia de Heroína/genética , Polimorfismo Genético , Adolescente , Adulto , Factores de Edad , Estudios de Casos y Controles , Femenino , Haplotipos , Humanos , Irán , Estimación de Kaplan-Meier , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple
10.
Int J Cancer ; 146(1): 18-25, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30891750

RESUMEN

Previous studies have reported an association between hot tea drinking and risk of esophageal cancer, but no study has examined this association using prospectively and objectively measured tea drinking temperature. We examined the association of tea drinking temperature, measured both objectively and subjectively at study baseline, with future risk of esophageal squamous cell carcinoma (ESCC) in a prospective study. We measured tea drinking temperature using validated methods and collected data on several other tea drinking habits and potential confounders of interest at baseline in the Golestan Cohort Study, a population-based prospective study of 50,045 individuals aged 40-75 years, established in 2004-2008 in northeastern Iran. Study participants were followed-up for a median duration of 10.1 years (505,865 person-years). During 2004-2017, 317 new cases of ESCC were identified. The objectively measured tea temperature (HR 1.41, 95% CI 1.10-1.81; for ≥60°C vs. <60°C), reported preference for very hot tea drinking (HR 2.41, 95% CI 1.27-4.56; for "very hot" vs. "cold/lukewarm"), and reported shorter time from pouring tea to drinking (HR 1.51, 95% CI 1.01-2.26; for <2 vs. ≥6 min) were all associated with ESCC risk. In analysis of the combined effects of measured temperature and amount, compared to those who drank less than 700 ml of tea/day at <60°C, drinking 700 mL/day or more at a higher-temperature (≥60°C) was consistently associated with an about 90% increase in ESCC risk. Our results substantially strengthen the existing evidence supporting an association between hot beverage drinking and ESCC.


Asunto(s)
Ingestión de Líquidos , Neoplasias Esofágicas/epidemiología , Carcinoma de Células Escamosas de Esófago/epidemiología , Calor , , Adulto , Anciano , Humanos , Irán , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo
11.
Int J Gynaecol Obstet ; 148(1): 59-64, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31569274

RESUMEN

OBJECTIVE: To compare the effect of gonadotropin-releasing hormone (GnRH) agonist microdose flare-up and GnRH agonist flare-up protocols among women with poor ovarian reserve undergoing intracytoplasmic sperm injection (ICSI) cycles. METHODS: Randomized controlled trial study among 131 women with poor ovarian reserve who underwent ICSI cycles at a single center in Tehran, Iran, between September 2008 and May 2014. Eligible women were randomly assigned to either the microdose flare-up (n=66) or flare-up (n=65) protocol. The primary outcome measure was live birth rate. RESULTS: Both groups were comparable in cycle cancellation, mean number of dominant follicles, retrieved oocytes, and metaphase II oocytes. Number of stimulation days (P=032) and endometrial thickness (P=0.001) were significantly higher, and gonadotropin dose was non-significantly higher (P=0.075) in the microdose flare-up group than in the flare-up group. No difference in clinical pregnancy, implantation, or abortion rate was observed between the two protocols. Live birth was higher in the microdose flare-up group than in the flare-up group (P=0.036). CONCLUSION: The microdose flare-up protocol seemed to be superior to the flare-up protocol, but it required a higher dose of gonadotropins and a longer duration of stimulation. Further prospective clinical trials of the microdose flare-up protocol are recommended. CLINICALTRIALS.GOV: NCT01006954.


Asunto(s)
Hormona Liberadora de Gonadotropina/agonistas , Antagonistas de Hormonas/administración & dosificación , Inducción de la Ovulación/métodos , Inyecciones de Esperma Intracitoplasmáticas/métodos , Adulto , Tasa de Natalidad , Relación Dosis-Respuesta a Droga , Femenino , Hormona Liberadora de Gonadotropina/administración & dosificación , Antagonistas de Hormonas/farmacología , Humanos , Irán , Nacimiento Vivo , Recuperación del Oocito/estadística & datos numéricos , Embarazo
12.
Food Chem ; 306: 125620, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31606627

RESUMEN

The lactic acid bacteria (LAB) and yeast strains with phytate degrading ability were isolated from Iranian traditional sourdough, and based on the acid and bile tolerance, three LAB and three yeast strains were selected and molecularly identified. In this study, baker's yeast (Saccharomyces cerevisiae) was considered as a positive control strain to investigate the nutritional and technological properties of the isolated strains. All of the identified microorganisms were characterized based on additional probiotic properties and were evaluated for nutritional and technological characteristics. The functional features are associated with degradation of phytate, antioxidant capacity, exopolysaccharides, phenolic compound content and in vitro starch digestion. Among all the tested strains the highest amount of phytase production capacity (1.64 Unit/ml) and lowest phytate content (17.49 mg/5 g) belonged to Kluyveromyces marxianus. According to the results, the bread prepared by using Kluyveromyces aestuarii possessed the highest porosity percentage (70.43%), and the lowest hardness (508.71 g).


Asunto(s)
Pan/análisis , Lactobacillales/metabolismo , Ácido Fítico/metabolismo , Saccharomyces cerevisiae/metabolismo , Triticum/química , 6-Fitasa/metabolismo , Pan/microbiología , Irán , Lactobacillales/aislamiento & purificación , Probióticos , Saccharomyces cerevisiae/aislamiento & purificación , Triticum/metabolismo
13.
J Environ Manage ; 254: 109767, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31704643

RESUMEN

This paper presents exergo-economic and enviro-economic assessment of a novel building integrated photovoltaic thermal-compound sensible rotary heat exchanger (BIPVT-SRHX) system. The innovative BIPVT-SRHX system preheats/precools the outdoor air in winter/summer and generates electric power. The performance of the system are analyzed from the energy/exergy viewpoints for Kermanshah, Iran climatic conditions. Then, the multi-objective genetic algorithm (MOGA) optimization is used to optimize to determine the optimum values of geometric and operating parameters in order to maximize the annual average exergo-economic and enviro-economic aspects of the system. The considered geometric and operating parameters include the length, width and depth of the air channel located underneath the PV modules, the air mass flow rate, and the diameter, rotational velocity and length of the SRHX. Moreover, the annual performance of the optimized and non-optimized BIPVT-SRHX systems are compared. The results showed that the annual average exergo-economic and enviro-economic aspects of the optimized BIPVT-SRHX system are 0.0076 $/annum and 246.9 kWh/$, respectively. Furthermore, it was found that the annual average enviro-economic aspect, annual average exergo-economic aspect, and yearly sum of CO2 mitigation of the optimized BIPVT-SRHX system are respectively 36.8%, 23.1% and 37.7% higher than the non-optimized system.


Asunto(s)
Electricidad , Calor , Irán , Estaciones del Año
14.
J Environ Manage ; 254: 109809, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31780269

RESUMEN

The municipal solid waste (MSW) landfills experience a large post-closure settlement over time. Waste settlement significantly impairs utilities, structures, and the other facilities constructed on top of a landfill. This study presents the settlement mechanisms and the methods of estimating MSW landfill settlements. Since the waste materials exhibit engineering properties which vary depending on many factors such as the location, time, climate, this study also presents the data related to the landfill characteristics, waste composition, waste moisture content, and other physical and chemical properties of waste. In addition, this paper discusses the findings of a settlement investigation conducted at a municipal solid waste landfill in Tehran. In this research, based on the collected field data and data obtained from the available literature, a technical management tool for MSW closed landfills has been developed using MATLAB, which aims to predict time dependent settlement under self-weight and surcharge loads in landfills considering various related parameters, leachate, gas generation, and moisture distribution, coefficients of compression, whilst it calculates different properties of wastes, and determines the landfill slope stability under various conditions. This user-friendly program captures the variation of the model parameters with time. The results of the verification process indicate that the results from the technical management tool have been in a very good agreement with the measured field settlement data, collected from Tehran landfill. Moreover, the results of sensitivity analysis of the model in regard to variation of input parameters indicate that there are two prominent characteristics, having significant impacts on the overall landfill settlement. These characteristics are the landfill height and the compressibility parameters. The outcomes of this study can improve the confidence for design and construction on MSW landfills. It may reduce the uncertainty when predicting the landfill settlement and enable to apply the landfill redevelopment techniques more effectively and efficiently. Studying the creep settlement properties under the co-effect of stress, biodegradation and temperature for predicting the total landfill settlement is recommended for future studies.


Asunto(s)
Eliminación de Residuos , Residuos Sólidos , Biodegradación Ambiental , Irán , Instalaciones de Eliminación de Residuos
15.
Insect Sci ; 27(1): 86-98, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29749703

RESUMEN

Bacterial endosymbionts play important roles in ecological traits of aphids. In this study, we characterize the bacterial endosymbionts of A. gossypii collected in Karaj, Iran and their role in the performance of the aphid. Our results indicated that beside Buchnera aphidicola, A. gossypii, also harbors both Hamiltonella defensa and Arsenophonus sp. Quantitative PCR (qPCR) results revealed that the populations of the endosymbionts increased throughout nymphal development up to adult emergence; thereafter, populations of Buchnera and Arsenophonus were diminished while the density of H. defensa constantly increased. Buchnera reduction caused prolonged development and no progeny production. Furthermore, secondary symbiont reduction led to reduction of the total life span and intrinsic rate of natural increase as well as appearance of the deformed dead offspring in comparison with the control insects. Reduction of the secondary symbionts did not affect parasitism rate of the aphid by the parasitic wasp Aphidius matricariae. Together these findings showed that H. defensa and Arsenophonus contributed to the fitness of A. gossypii by enhancing its performance, but not through parasitoid resistance.


Asunto(s)
Áfidos/microbiología , Áfidos/fisiología , Buchnera/fisiología , Enterobacteriaceae/fisiología , Simbiosis , Animales , Áfidos/crecimiento & desarrollo , Irán , Ninfa/crecimiento & desarrollo , Ninfa/microbiología , Reproducción , Especificidad de la Especie
16.
Chemosphere ; 240: 124983, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31726590

RESUMEN

There is limited information about pesticide contamination in Iran's agricultural land, particularly in plains producing exportable fruits. The aim of this investigation was to evaluate the concentration of organochlorine pesticides (OCPs) including hexachlorocyclohexane (HCH), heptachlor, dichloro-diphenyl-trichloroethane (DDT), chlordane (CHL), and their isomers compounds in agricultural soils of southern Iran. A total of 28 topsoil samples were collected from agricultural lands of Dalaki and Shabankare areas, Bushehr, Iran. In Dalaki area, the mean value of ΣHCH (α, ß, γ, δ), ΣDDT (o,p-DDE, o,p-DDD, o,p-DDT, p,p-DDE, p,p-DDD, p,p-DDT, and DDT), and ΣCHL (Trans-chlordane, Cis-chlordane, Heptachlor-exo-epoxide, and Heptachlor) was found to be 0.411 ng/g (dry weight, dw), 4.37 ng/g dw, and 2.04 ng/g dw, respectively. In Shabankare area the mean value of ΣHCH, ΣDDT, and ΣCHL was measured to be 1.38 ng/g dw, 11.99 ng/g dw, and 1.62 ng/g dw, respectively. The concentration trend of pesticides in both areas was as follows: DDT > CHL > HCH. Source identification indicated recent usage of HCH and DDT in the studied areas. Obtaining a cis-chlordane/trans-chlordane ratio greater than one in Shabankare farmlands showed that chlordane was not used recently. The health risk assessment showed that children and adults groups in both areas are exposed to negligible cancer risk. More serious attempts are necessary to reduce usage of OCPs during the agricultural process and the protection of soil and human health in the studied areas.


Asunto(s)
Agricultura , Plaguicidas/análisis , Contaminantes del Suelo/análisis , Adulto , Niño , Clordano , Diclorodifenil Dicloroetileno , Monitoreo del Ambiente , Heptacloro , Hexaclorociclohexano , Humanos , Hidrocarburos Clorados/análisis , Irán , Medición de Riesgo , Suelo , Tricloroetanos
17.
Ecotoxicol Environ Saf ; 187: 109838, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31677564

RESUMEN

Due to population growth and the considerable increase in usage of the resources, Human environment quality has been highly threatened by pollutants in recent decades. Polycyclic aromatic hydrocarbons (PAHs) are widespread, persistent organic pollutants which are of great concern due to their carcinogenicity. The present study is the first investigation that assesses contamination, sources and cancer risk of 16 priority PAHs proposed by US EPA in urban dust samples (n = 80) taken in different land-uses of Tehran metropolis, the capital of Iran. Gas chromatography-mass spectrometry (GC-MS) is used to measure PAHs concentrations. The results showed that the average concentration of the total 16 PAHs and the average Benzo[a]pyrene total potency equivalency were 566 µg kg-1 dry weight and 36.4 µg kg-1, respectively. In the commercial and residential land-uses high molecular weight (HMW) PAHs were dominated, whereas in green lands, light molecular weight (LMW) PAHs showed maximum contribution. The highest concentration of total PAHs were observed in the commercial areas due to limited air circulation and heavy traffic loads. Incremental Lifetime Cancer Risk (ILCR) model was applied to evaluate the cancer risk of exposure to PAHs contaminated dust. Based on the results, Tehran's residents (children and adults) in various land-uses except for green lands, are in high potential cancer risk of PAHs via ingestion and dermal contact exposure routs. Ace, Chr, Pyr, and BghiP which are indicators of traffic emissions, were found to be predominant PAH contributors in urban dust of commercial areas. Also, Ace, Fl, Phe, and BghiP which are derived from fossil fuel combustion, were mainly observed in the industrial land-use. Based on the results of factor analysis and diagnostic ratios, Diesel/gasoline engine vehicular emissions and combustion were found to be the main sources of PAHs in urban dust of Tehran.


Asunto(s)
Polvo/análisis , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Neoplasias/epidemiología , Hidrocarburos Policíclicos Aromáticos/análisis , Adulto , Niño , Ciudades , Gasolina/análisis , Humanos , Industrias , Irán , Medición de Riesgo , Emisiones de Vehículos/análisis
18.
Nurs Adm Q ; 44(1): E1-E10, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31789753

RESUMEN

The objective of this study was to evaluate sleep quality and its relationship to cognitive factors among nurses. Sleep quality among nurses is an important issue, which requires more extensive study. Its correlation with cognitive ability has not been sufficiently considered. Five hundred forty nurses (66.3% female) working in 6 hospitals were selected as the sample of the study. Results show that nurses do not experience good quality of sleep. That is, 77.4% of the sample population of nurses have a poor quality of sleep, and nurses working the night shift have more sleep problems than other nurses. The results show that there is a relationship between dysfunctional beliefs and attitudes about sleep and metacognitive process and the quality of sleep, and that these variables can predict sleep quality. Based on the results of the study, it can be said that cognitive and metacognitive processes play an important role in sleep quality. Lack of sufficient sleep can create numerous problems for nurses and patients. Attention to the role of cognitive and metacognitive processes can help improve the sleep quality of nurses.


Asunto(s)
Cognición , Personal de Enfermería en Hospital/psicología , Trastornos del Sueño-Vigilia , Sueño/fisiología , Adulto , Femenino , Humanos , Irán , Masculino , Persona de Mediana Edad , Enfermeras Internacionales , Horario de Trabajo por Turnos , Tolerancia al Trabajo Programado , Adulto Joven
19.
Environ Monit Assess ; 192(1): 25, 2019 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-31823028

RESUMEN

It is well documented that standalone machine learning methods are not suitable for rainfall forecasting in long lead-time horizons. The task is more difficult in arid and semiarid regions. Addressing these issues, the present paper introduces a hybrid machine learning model, namely multiple genetic programming (MGP), that improves the predictive accuracy of the standalone genetic programming (GP) technique when used for 1-month ahead rainfall forecasting. The new model uses a multi-step evolutionary search algorithm in which high-performance rain-borne genes from a multigene GP solution are recombined through a classic GP engine. The model is demonstrated using rainfall measurements from two meteorology stations in Lake Urmia Basin, Iran. The efficiency of the MGP was cross-validated against the benchmark models, namely standard GP and autoregressive state-space. The results indicated that the MGP statistically outperforms the benchmarks at both rain gauge stations. It may reduce the absolute and relative errors by approximately up to 15% and 40%, respectively. This significant improvement over standalone GP together with the explicit structure of the MGP model endorse its application for 1-month ahead rainfall forecasting in practice.


Asunto(s)
Predicción/métodos , Meteorología/métodos , Modelos Genéticos , Lluvia , Algoritmos , Irán
20.
Epidemiol Health ; 41: e2019049, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31801319

RESUMEN

OBJECTIVES: This study was conducted to identify and characterize the barriers and motivations to physical activity (PA) for elderly adults in Iran and other countries. METHODS: We searched 6 databases (PubMed, Embase, Scopus, Web of Science, Magiran, and the Scientific Information Database) from 2000 to the November 2017, using "aged 60 and over," "physical activity" or "exercise," and "motivator" and "barrier" as keywords. Two reviewers independently performed the search, screening, and quality assessment of the studies. RESULTS: In total, 34 papers were finally included in the study. The most important barriers, based on the frequency of factors, included physical problems, having no companions, and physical barriers to walking. The motivators included improving one's physical condition, being social, and suitability of the physical environment. CONCLUSIONS: Important motivators and barriers to PA were more closely related to intrapersonal factors than to the interpersonal and environmental domains. The barriers and motivators to PA in the elderly were not markedly different between Iran and other countries. Therefore, a general strategy could be designed to improve PA in the elderly.


Asunto(s)
Ejercicio , Anciano , Ejercicio/psicología , Humanos , Internacionalidad , Irán , Motivación
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