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1.
Environ Sci Pollut Res Int ; 23(4): 3285-99, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26490904

RESUMO

Measurements of natural radioactivity levels and heavy metals in sediment and soil samples of the Anzali international wetland were carried out by two HPGe-gamma ray spectrometry and atomic absorption spectroscopy techniques. The concentrations of (235)U, (226)Ra, (232)Th, (40)K, and (137)Cs in sediment samples ranged between 1.05 ± 0.51-5.81 ± 0.61, 18.06 ± 0.63-33.36 ± .0.34, 17.57 ± 0.38-45.84 ± 6.23, 371.88 ± 6.36-652.28 ± 11.60, and 0.43 ± 0.06-63.35 ± 0.94 Bq/kg, while in the soil samples they vary between 2.36-5.97, 22.71-38.37, 29.27-42.89, 472.66-533, and 1.05-9.60 Bq/kg for (235)U, (226)Ra, (232)Th, (40)K, and (137)Cs, respectively. Present results are compared with the available literature data and also with the world average values. The radium equivalent activity was well below the defined limit of 370 Bq/kg. The external hazard indices were found to be less than 1, indicating a low dose. Heavy metal concentrations were found to decrease in order as Fe > Mn > Sr > Zn > Cu > Cr > Ni > Pb > Co > Cd. These measurements will serve as background reference levels for the Anzali wetland.


Assuntos
Radioisótopos de Césio/análise , Metais Pesados/análise , Radioisótopos de Potássio/análise , Rádio (Elemento)/análise , Poluentes Radioativos do Solo/análise , Tório/análise , Urânio/análise , Espectrometria gama/métodos , Espectrofotometria Atômica/métodos , Áreas Alagadas
2.
J Environ Radioact ; 144: 134-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25847859

RESUMO

Portable high-resolution gamma-ray spectrometry was carried out to determine the natural radioactivity levels in high volume surface water samples of the northern coast of Oman Sea, covering the coastal strip from Hormoz strait to Goatr seaport, for the first time. The water samples from 36 coastal and near shore locations were collected for analysis. Analyses on the samples collected were carried out to determine (226)Ra, (232)Th and (40)K contents. The concentration of (226)Ra, (232)Th and (40)K in surface water samples ranged between 2.19 and 2.82 Bq/L, 1.66-2.17 Bq/L and 132.6-148.87 Bq/L, respectively. The activity profile of radionuclides shows low activity across the study area. The study also examined some radiation hazard indices. The external hazard index was found to be less than 1, indicating a low dose. The results of measurements will serve as background reference level for Oman Sea coastlines.


Assuntos
Radiação de Fundo , Monitoramento de Radiação , Poluentes Radioativos da Água/análise , Irã (Geográfico) , Oceanos e Mares , Espectrometria gama
3.
Mar Pollut Bull ; 92(1-2): 201-211, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25561003

RESUMO

This study aims to establish a managed sampling plan for rapid estimate of natural radio-nuclides diffusion in the northern coast of the Oman Sea. First, the natural radioactivity analysis in 36 high volume surface water samples was carried out using a portable high-resolution gamma-ray spectrometry. Second, the oceanic currents in the northern coast were investigated. Then, the third generation spectral SWAN model was utilized to simulate wave parameters. Direction of natural radioactivity propagation was coupled with the preferable wave vectors and oceanic currents direction that face to any marine pollution, these last two factors will contribute to increase or decrease of pollution in each grid. The results were indicated that the natural radioactivity concentration between the grids 8600 and 8604 is gathered in the grid 8600 and between the grids 8605 and 8608 is propagated toward middle part of Oman Sea.


Assuntos
Monitoramento Ambiental/métodos , Radioisótopos/análise , Modelos Teóricos , Oceanos e Mares , Omã , Água do Mar/análise , Água do Mar/química , Espectrometria gama/métodos
4.
Mar Pollut Bull ; 64(9): 1956-61, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22717321

RESUMO

The natural radioactivity levels in sediment samples of the northern coast of Oman Sea, covering the coastal strip from Hormoz canyon to Goatr seaport, as the first time has been determined. The results of measurements will serve as background reference level for Oman Sea coastlines. Sediments from 36 coastal and near shore locations were collected for analysis. Analysis on the collected samples were carried out to determine (235)U, (238)U, (232)Th, (40)K and (137)Cs using two high purity germanium detectors with 38.5% and 55% relative efficiencies. The concentration of (235)U, (238)U, (232)Th, (40)K and (137)Cs in sediment samples ranged between 1.01 and 2.87 Bq/kg, 11.83 and 22.68 Bq/kg, 10.7 and 25.02 Bq/kg, 222.89 and 535.07 Bq/kg and 0.14 and 2.8 Bq/kg, respectively. The radium equivalent activity was well below the defined limit of 370 Bq/kg. The external hazard indices were found to be less than 1, indicating a low dose.


Assuntos
Sedimentos Geológicos/química , Monitoramento de Radiação , Poluentes Radioativos da Água/análise , Radioisótopos de Césio/análise , Oceanos e Mares , Omã , Radioisótopos de Potássio/análise , Espectrometria gama , Tório/análise , Urânio/análise , Contaminação Radioativa da Água/estatística & dados numéricos
5.
Iran Biomed J ; 11(3): 147-52, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18051774

RESUMO

BACKGROUND: Viral protein-1 (VP1) is a major capsid protein of Coxsakievirus B3 (CVB3) that plays an important role in directing viruses towards permissive cells and acts as a main antigenic site of the virus in eliciting of host immune response, hence it seems VP1 can be considered as a vaccine candidate against CVB3 infection. In this study, cDNA of VP1 was prepared, cloned into pET expression vector and the recombinant protein (VP1) was over expressed in E. coli. METHODS: The viruses were grown in suspension cultures of Vero cells with an input virus multiplicity of 10-50 plaque-forming units/cell. After observing complete cytopathic effect, the total RNA (cells and virus) was prepared for RT-PCR and by using specific primers, VP1 cDNA was amplified and ligated into pET vectors (32 a and 28 a). The recombinant vector was transferred into competent E. coli (BL-21) and after selection of proper colony, which carried correct cDNA within the vector; cells were cultured and induced with isopropyl B-D-thiogalactopyranoside, in order to express protein (VP1). The cultures were tested for presence of VP1 by SDS-PAGE and Western-Blotting analysis. RESULTS: Molecular techniques such as PCR which showed exact defined size of the VP1 (819 bp), restriction digestion and finally immunoblot analysis of over expressed protein; all confirmed the correct cloning and expression of VP1 in this research. CONCLUSION: In this research, full length of VP1 as major capsid protein of CVB3 was over expressed in E. coli which, can be used for further studies, including neutralizing antibody production against CVB3.


Assuntos
Enterovirus Humano B/genética , Proteínas Estruturais Virais/genética , Animais , Sequência de Bases , Chlorocebus aethiops , Clonagem Molecular , Primers do DNA/genética , DNA Viral/genética , Enterovirus Humano B/classificação , Enterovirus Humano B/patogenicidade , Escherichia coli/genética , Expressão Gênica , Genes Virais , Vetores Genéticos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Vero , Proteínas Estruturais Virais/biossíntese , Proteínas Estruturais Virais/química
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