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1.
Analyst ; 143(5): 1281, 2018 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-29424848

RESUMO

Correction for 'Physical and compositional analysis of differently cultured 3D human skin equivalents by confocal Raman spectroscopy' by Y. Dancik, et al., Analyst, 2018, DOI: .

2.
Analyst ; 143(5): 1065-1076, 2018 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-29368763

RESUMO

Three-dimensional skin equivalents are increasingly gaining acceptance as non-animal based experimental models of human skin. They are particularly suited to studying differences in physical and compositional properties of normal and diseased skin and their impact on the skin's barrier function. Typically, a culture protocol yielding a model of normal skin is modified to create a model simulating a pathology. Skin layer thicknesses and lipid/protein contents are compared using methods that are invasive, precluding further experiments on the same replicates, and which may be prone to artefacts. We show here that confocal Raman spectroscopy (CRS) is a valuable method for non-invasive discrimination of skin equivalents grown under different culture conditions. Using 3D full-thickness skin equivalents developed in-house, we measure significant differences in stratum corneum and viable epidermis apparent thicknesses resulting from a 7-day difference in the cultures' air-lift phase and from supplementation of the culture medium with interleukin 4. Furthermore, stratum corneum thicknesses obtained by CRS are up to 2.6-fold higher than values measured from histological photomicrographs. Regarding composition, CRS reveals the differential effects of the culture protocol modifications on ceramide, cholesterol and protein composition as a function of depth in the stratum corneum.


Assuntos
Técnicas de Cultura de Órgãos , Pele/química , Análise Espectral Raman , Ceramidas/análise , Colesterol/análise , Epiderme/química , Fibroblastos , Humanos , Queratinócitos , Lipídeos/análise , Proteínas/análise , Pele Artificial
3.
Indian J Occup Environ Med ; 21(2): 56-76, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29540967

RESUMO

BACKGROUND: With the growing numbers of iron ore pelletization industries in India, various impacts on environment and health in relation to the workplace will rise. Therefore, understanding the hazardous process is crucial in the development of effective control measures. Hazard Identification, Risk Assessment, and Control measures (HIRAC) acts as an effective tool of Occupational Health Assessment. OBJECTIVE: The aim of the study was to identify all the possible hazards at different workplaces of an iron ore pelletizing industry, to conduct an occupational health risk assessment, to calculate the risk rating based on the risk matrix, and to compare the risk rating before and after the control measures. MATERIALS AND METHODS: The research was a cross-sectional study done from March to December 2015 in an iron ore pelletizing industry located in Odisha, India. Data from the survey were collected by inspecting the workplace, responses of employees regarding possible hazards in their workplace, reviewing department procedure manual, work instructions, standard operating procedure, previous incident reports, material safety data sheet, first aid/injury register, and health record of employees. RESULTS: A total of 116 hazards were identified. Results of the paired-sample's t-test showed that mean risk rating differs before taking control measures (M = 9.13, SD = 5.99) and after taking control measures (M = 2.80, SD = 1.38) at the 0.0001 level of significance (t = 12.6428, df = 115, N = 116, P < 0.0001, 95% CI for mean difference 5.34 to 7.32). On an average, risk reduction was about 6.33 points lower after taking control measures. CONCLUSION: The hazards having high-risk rating and above were reduced to a level considered As Low as Reasonably Practicable (ALARP) when the control measures were applied, thereby reducing the occurrence of injury or disease in the workplace.

4.
J Nanosci Nanotechnol ; 12(3): 1835-42, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22754988

RESUMO

Amorphous carbon (a-C) nanoclusters were synthesized by the implantation of carbon ions (C-) into thermally grown silicon dioxide film (-500 nm thick) on a Si (100) wafer and processed by high temperature thermal annealing. The carbon ions were implanted with an energy of 70 keV at a fluence of 5 x 10(17) atoms/cm2. The implanted samples were annealed at 1100 degrees C for different time periods in a gas mixture of 96% Ar+4% H2. Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and High Resolution Transmission Electron Microscopy (HRTEM) were used to study the structural properties of both the as-implanted and annealed samples. HRTEM reveals the formation of nanostructures in the annealed samples. The Raman spectroscopy also confirms the formation of carbon nano-clusters in the samples annealed for 10 min, 30 min, 60 min and 90 min. No Raman features originating from the carbon-clusters are observed for the sample annealed further to 120 min, indicating a complete loss of implanted carbon from the SiO2 layer. The loss of the implanted carbon in the 120 min annealed sample from the SiO2 layer was also observed in the XPS depth profile measurements. Room temperature photoluminescence (PL) spectroscopy revealed visible emissions from the samples pointing to carbon ion induced defects as the origin of a broad 2.0-2.4 eV band, and the intrinsic defects in SiO2 as the possible origin of the -2.9 eV bands. In low temperature photoluminescence spectra, two sharp and intense photoluminescence lines at -3.31 eV and -3.34 eV appear for the samples annealed for 90 min and 120 min, whereas no such bands are observed in the samples annealed for 10 min, 30 min, and 60 min. The Si nano-clusters forming at the Si-SiO2 interface could be the origin of these intense peaks.

5.
J Phys Condens Matter ; 22(7): 072203, 2010 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-21386375

RESUMO

We report on the formation of UV emitting Si nanoclusters (NCs) in Si, using a two stage Au implantation technique. These Si NCs, with an average size of 2 nm, show photoluminescence at room temperature, over a narrow band of about 100 meV with a peak of emission near 3.3 eV. With emission lifetimes in the range of 1.5-2.5 ns, the transitions seem to come from excitonic recombinations across a quasi-direct gap. Since the structures are below the surface, there is no adverse effect of oxidation resulting in a shift in emission wavelength. On the other hand, an annealing at 500 °C has been found to result in a significant increase in the emission intensity. This is due to localized plasmon induced electric field enhancement in Au nano-islands in the vicinity.


Assuntos
Ouro/química , Nanoestruturas/química , Nanotecnologia , Silício/química , Raios Ultravioleta , Tamanho da Partícula , Propriedades de Superfície
6.
Trop Biomed ; 27(3): 578-84, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21399600

RESUMO

Understanding the genetic diversity, extent and distribution of variant forms of Plasmodium vivax parasites is crucial in the development of effective control measures and in Orissa, a hyperendemic state in the eastern part of India, the polymorphic nature of P. vivax isolates is largely lacking. The result of the study analyzing two highly polymorphic single copy genes for P. vivax circumsporozoite protein (pvcs) and P. vivax merozoite surface protein 3α (pvmsp3α) shows that the parasite population is highly heterogenous (33 distinct genotype from 35 isolates) in Orissa. However, the observation of the multiplicity of infection value of 1.34 and high frequency distribution of certain genotype with respect to individual marker (the VK247b allele with a frequency of 0.37; VK210e with 0.25 and VK210c with 0.14) suggests that the parasite population are likely to be under selective pressure and may either be due to preferential production of sporozoites carrying these variants in the available anopheline mosquito species of the state or selection of particular genotypes by host immune pressure. Moreover, although P. vivax in South-East Asia indicates an overall predominance of VK210 which is thought to be the best adapted variant of pvcs repeat type, the almost equal prevalence of both repeat type of pvcs; VK210 and VK247 in the present study is unexpected and needs further study for clarification.


Assuntos
Variação Genética , Malária Falciparum/epidemiologia , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Plasmodium vivax/classificação , Plasmodium vivax/genética , Antígenos de Protozoários/genética , DNA de Protozoário/genética , Frequência do Gene , Humanos , Índia/epidemiologia , Proteínas de Protozoários/genética , Seleção Genética
7.
Int J Occup Environ Health ; 7(2): 153-64, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11373048

RESUMO

Based on a mix of official data and results of a survey conducted in May-June 2000 as part of an ongoing Swedish-Indian-Chinese collaborative study, this paper describes the working conditions of workers engaged in rural industry in India. First, it reports the education and skills of such workers. Educational attainment is presented in terms of both general and technical education. The role played by public institutions in the development of skills is examined. A view of the environment in which these workers work, on the one hand, and the physical/economic conditions of work, on the other, is then developed. Locational and gender disparities are illustrated by rural-urban and male-female comparisons to the extent that the available data permit. Child labor is briefly discussed. The findings are disturbing. The authors offer suggestions for improvement.


Assuntos
Emprego/estatística & dados numéricos , Indústrias , Capacitação em Serviço/estatística & dados numéricos , China , Escolaridade , Indústrias/organização & administração , Indústrias/estatística & dados numéricos , População Rural , Recursos Humanos
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