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1.
Forensic Sci Med Pathol ; 16(2): 207-215, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32410108

RESUMO

In an examination of three unwrapped mummified children from the Graeco-Roman Period of ancient Egypt there was an unexpected finding of fair hair. In the majority of unwrapped ancient Egyptian mummified bodies the hair was not fair but rather dark brown or black. To determine if exposure to natron during the mummification process was responsible for the fair hair color an experiment was carried out to partially replicate the environment in which bodies were desiccated. Fourteen samples of modern hair from various age groups, sex and ethnicity were subjected to synthetic natron for a period of 40 days to replicate the time taken to mummify a body. Macroscopic and microscopic examinations of samples were employed to ascertain any significant changes in hair color after treatment. Ancient wigs were studied for evidence of post mortem changes to hair color since construction over 2,000 years ago. Results of the study showed no significant lightening of hair color and in several samples the hair significantly darkened as the result of exposure to the natron. There was not any evidence that hair lightened as the result of natural post mortem changes and this was confirmed by the study of the natural hair wigs that had not changed color post mortem. This study concluded that the fair hair observed in the three child mummies was not the result of exposure to natron or post mortem changes but rather it was probably due to ancestry because of the presence of diverse genomes that were introduced into ancient Egypt during the Greco-Roman Period.


Assuntos
Embalsamamento/métodos , Cor de Cabelo , Múmias , Grupos Raciais , Carbonatos/química , Criança , Egito , Feminino , Mundo Grego , Cabelo/anatomia & histologia , História Antiga , Humanos , Masculino , Microscopia , Mundo Romano , Bicarbonato de Sódio/química , Cloreto de Sódio/química , Sulfatos/química
2.
J Forensic Sci ; 59(1): 117-22, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24117678

RESUMO

Reflected ultraviolet imaging techniques allow for the visualization of evidence normally outside the human visible spectrum. Specialized digital cameras possessing extended sensitivity can be used for recording reflected ultraviolet radiation. Currently, there is a lack of standardized methods for ultraviolet image recording and processing using digital cameras, potentially limiting the implementation and interpretation. A methodology is presented for processing ultraviolet images based on linear responses and the sensitivity of the respective color channels. The methodology is applied to a FujiS3 UVIR camera, and a modified Nikon D70s camera, to reconstruct their respective spectral sensitivity curves between 320 and 400 nm. This method results in images with low noise and high contrast, suitable for qualitative and/or quantitative analysis. The application of this methodology is demonstrated in the recording of latent fingerprints.

3.
PLoS One ; 8(11): e79534, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24260244

RESUMO

Linear camera responses are required for recovering the total amount of incident irradiance, quantitative image analysis, spectral reconstruction from camera responses and characterisation of spectral sensitivity curves. Two commercially-available digital cameras equipped with Bayer filter arrays and sensitive to visible and near-UV radiation were characterised using biexponential and Bézier curves. Both methods successfully fitted the entire characteristic curve of the tested devices, allowing for an accurate recovery of linear camera responses, particularly those corresponding to the middle of the exposure range. Nevertheless the two methods differ in the nature of the required input parameters and the uncertainty associated with the recovered linear camera responses obtained at the extreme ends of the exposure range. Here we demonstrate the use of both methods for retrieving information about scene irradiance, describing and quantifying the uncertainty involved in the estimation of linear camera responses.


Assuntos
Fotografação/métodos , Raios Ultravioleta , Processamento de Imagem Assistida por Computador
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