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1.
J Radiol Prot ; 44(2)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38838649

RESUMEN

Protection against ionizing radiations is important in laboratories with radioactive materials and high energy cyclotron beams. The Cyclotron and Radioisotope Center (CYRIC) located in Tohoku University in Miyagi prefecture, Japan and is a well-known nuclear science laboratory with cyclotron beams and substantial number of high activity radioactive materials. Considering this, it is important to perform complete radiation transport computations to ensure the safety of non-occupational and occupational workers. In the present work, we have developed a complete 3-dimensional model of the main cyclotron building and radiation labs using Monte Carlo method. We have found that the dispersed photons and neutrons inside and in the surrounding of the CYRIC building pose no significant risk to occupational and non-occupational workers. The present work and the developed models would be useful in the field of radiation protection.


Asunto(s)
Ciclotrones , Método de Montecarlo , Protección Radiológica , Japón , Exposición Profesional/prevención & control , Exposición Profesional/análisis , Dosis de Radiación , Simulación por Computador , Humanos , Universidades
2.
New Phytol ; 193(3): 650-664, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22142234

RESUMEN

• Inorganic arsenic (As(i) ) in rice (Oryza sativa) grains is a possible threat to human health, with risk being strongly linked to total dietary rice consumption and consumed rice As(i) content. This study aimed to identify the range and stability of genetic variation in grain arsenic (As) in rice. • Six field trials were conducted (one each in Bangladesh and China, two in Arkansas, USA over 2 yr, and two in Texas, USA comparing flooded and nonflood treatments) on a large number of common rice cultivars (c. 300) representing genetic diversity among international rice cultivars. • Within each field there was a 3-34 fold range in grain As concentration which varied between rice subpopulations. Importantly, As(i) correlated strongly with total As among a subset of 40 cultivars harvested in Bangladesh and China. • Genetic variation at all field sites was a large determining factor for grain As concentration, indicating that cultivars low in grain As could be developed through breeding. The temperate japonicas exhibited lower grain As compared with other subpopulations. Effects for year, location and flooding management were also statistically significant, suggesting that breeding strategies must take into account environmental factors.


Asunto(s)
Arsénico/metabolismo , Variación Genética , Oryza/crecimiento & desarrollo , Oryza/genética , Semillas/genética , Semillas/metabolismo , Arkansas , Bangladesh , China , Flores/fisiología , Oryza/metabolismo , Brotes de la Planta/genética , Brotes de la Planta/metabolismo , Texas
3.
Environ Int ; 153: 106529, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33784587

RESUMEN

High levels of arsenic in drinking water and food materials continue to pose a global health challenge. Over 127 million people alone in Bangladesh (BD) and West Bengal (WB) state of India are exposed to elevated levels of arsenic in drinking water. Despite decades of research and outreach, arsenic awareness in communities continue to be low. Specifically, very few studies reported arsenic awareness among low-income farming communities. A comprehensive approach to assess arsenic awareness is a key step in identifying research and development priorities so that appropriate stakeholder engagement may be designed to tackle arsenic menace. In this study, we developed a comprehensive arsenic awareness index (CAAI) and identified key awareness drivers (KADs) of arsenic to help evaluate farmers' preferences in dealing with arsenic in the environment. The CAAI and KADs were developed using a questionnaire survey in conjunction with ten machine learning (ML) models coupled with a hybrid feature selection approach. Two questionnaire surveys comprising of 73 questions covering health, water and community, and food were conducted in arsenic-affected areas of WB and BD. Comparison of CAAIs showed that the BD farmers were generally more arsenic-aware (CAAI = 7.7) than WB farmers (CAAI = 6.8). Interestingly, the reverse was true for the awareness linked to arsenic in the food chain. Application of hybrid feature selection identified 15 KADs, which included factors related to stakeholder interventions and cropping practices instead of commonly perceived factors such as age, gender and income. Among ML algorithms, classification and regression trees and single C5.0 tree could estimate CAAIs with an average accuracy of 84%. Both communities agreed on policy changes on water testing and clean water supply. The CAAI and KADs combination revealed a contrasting arsenic awareness between the two farming communities, albeit their cultural similarities. Specifically, our study shows the need for increasing awareness of risks through the food chain in BD, whereas awareness campaigns should be strengthened to raise overall awareness in WB possibly through media channels as deemed effective in BD.


Asunto(s)
Arsénico , Contaminantes Químicos del Agua , Arsénico/análisis , Bangladesh , Agricultores , Humanos , India , Aprendizaje Automático , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua
4.
Prenat Diagn ; 18(8): 822-5, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9742570

RESUMEN

Recently we identified a P408S, P415L allele of beta-glucuronidase in several Mexican patients with mucopolysaccharidosis type VII (Sly syndrome) and presented evidence that both mutations are required to produce the MPS VII allele (Islam et al., 1996). In an attempt to determine whether either of these mutations exists as a benign polymorphism among Mexicans, we developed a PCR method to screen simultaneously for both mutations and used it to screen a population sample of 187 Mexican individuals in the Guadalajara area, all from the north-western states of Mexico. Neither mutation was present in 374 alleles studied. In addition, we had the opportunity to carry out prenatal diagnosis in a fetus at risk for homozygosity for this MPS VII allele at the 15th week of gestation using enzymatic assays as well as by analysis of genomic DNA isolated from cultured amniotic fluid cells. The fetus was found to be heterozygous for the P408S, P415L allele. The newborn's heterozygosity was confirmed after birth by enzyme assays on plasma and leukocytes, and by analysis of DNA from leukocytes.


Asunto(s)
Alelos , Glucuronidasa/genética , Mucopolisacaridosis VII/genética , Mutación , Diagnóstico Prenatal , Líquido Amniótico/citología , Células Cultivadas , ADN/análisis , ADN/aislamiento & purificación , Edad Gestacional , Heterocigoto , México , Mucopolisacaridosis VII/diagnóstico , Reacción en Cadena de la Polimerasa
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