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1.
Phys Med ; 32(9): 1052-64, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27618585

RESUMEN

Dynamic AngioThermography (DATG) is a contact-plate technique capable of producing a digital representation of breast vascularity. The inception and growth of a tumor are associated with neoangenesis, which may result in a demonstrable alteration in the regional blood flow, while in normal health conditions the vascularity remains unchanged throughout life. DATG, if included in the clinical evaluation for breast cancer, could potentially improve the accuracy of the diagnosis of this disease. Conventional DATG is limited, however, in that it is a projection (i.e. two-dimensional) imaging technique that does not provide any information on the depth and its effect on the pattern of the perfusion revealed by this technique. In fact, the blood pattern is detected by projecting temperature signals on the plate, thus acquiring a digital two-dimensional image. In this article we propose a new approach for extracting information on depth through the inversion of the Fourier heat equation. The idea is to extract the information along the third axis while acquiring and analyzing the temporal sequence during the process of image formation. The method implemented has been tested on a dedicated "electric phantom" and in one in vivo experiment. In spite of the limits of these preliminary tests, the experimental results have shown that this method makes it possible to obtain a 3D representation of the vascularity. Although it appears to be promising, further validation and characterization of our technique are required.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Fantasmas de Imagen , Tomografía Computarizada por Rayos X , Algoritmos , Diseño de Equipo , Femenino , Calor , Humanos , Modelos Estadísticos , Reproducibilidad de los Resultados , Programas Informáticos
2.
Int J Paleopathol ; 7: 64-69, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29539492

RESUMEN

The famous castrato singer Carlo Broschi, better known as Farinelli (1705-1782), was exhumed by our research group in July 2006 to study his skeletal remains and reconstruct his osteobiography. He was castrated before puberty to preserve his high voice into adulthood. The osteological study has revealed several skeletal features probably related to the effects of castration (Hyperostosis frontalis interna, long limb bones, persistence of epiphyseal lines, osteoporosis) (Belcastro et al., 2011). Here we present the study of the teeth and maxilla-mandibular region using classic and tomographic morphological methods. Considering the subject's age and the period during which he lived, his oral health conditions were good. On the basis of the very pronounced anomalous vestibular buccal wear, a overbite visualized by 3D reconstruction, was hypothesized. This facial disharmony is of particular interest when considering Farinelli's extraordinary singing qualities and stage presence.

3.
Ann Occup Hyg ; 43(2): 117-24, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10206040

RESUMEN

Potential health hazards due to fibre inhalation are only evaluated in a limited way by simple optical microscopy examination of the membrane filters on which the fibres have been collected. One must consider the amount of fibres deposited and persisting in the most vulnerable organ compartments. Exposure evaluated in this way must take account of the deposition efficiency and relative clearance efficiency of different regions of the respiratory tract, which depends mainly on the diameter and length distribution of the fibres. The fibre diameter roughly indicates the deposition site in the respiratory tract, while the length is mainly connected with toxicity. For these reasons, at international level, special samplers have been recently proposed, capable of distinguishing the fibre sizes, in order to separate the so-called 'thoracic fraction' (the total fibres which penetrate beyond the larynx) and the 'respirable fraction' (only the fibres reaching the non ciliated respiratory area), which represent the most interesting sizes as far as health effects are concerned. Our purpose in this context is to explore the feasibility of using the Inertial Spectrometer (INSPEC) as a sampler that separates the fibres according to their aerodynamic diameter. The optical and electron microscope observations of the samples demonstrate a satisfactory size separation of the fibres and alignment along the flow lines. Therefore, INSPEC is successful in restricting the microscopic analyses to the potentially noxious fibres and in assessing specific concentrations for each diameter interval.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Monitoreo del Ambiente/métodos , Espectrometría de Masas/métodos , Fibras Minerales/análisis , Aerosoles , Monitoreo del Ambiente/instrumentación , Estudios de Factibilidad , Humanos , Espectrometría de Masas/instrumentación , Tamaño de la Partícula , Reproducibilidad de los Resultados
4.
Health Phys ; 58(3): 329-39, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2312297

RESUMEN

Strontium-90 is of relevant biological importance among fission products released during a fission reactor accident. Rapid information on its concentration in environmental matrices is extremely valuable, yet this implies chemical separations and handling with a shift in daughter equilibrium and therefore the need to wait a sufficient time for the equilibrium to be reestablished. The work concerns a feasibility study of a multi-detector system for a prompt evaluation of the 90Sr activity or, at least, a prompt determination of its order of magnitude in the presence of other pure beta and beta-gamma emitters; their interferences are examined on the basis of the Chernobyl releases and their decay properties. The technique is based on a plastic scintillator beta detector and a guard ring of BGO counters which can be logically connected in coincidence and anticoincidence. The evaluations show that a few hours are sufficient to determine a specific activity comparable with the Maximum Permissible Concentration in air by sampling 10 m3.


Asunto(s)
Accidentes , Contaminantes Ambientales/análisis , Reactores Nucleares , Monitoreo de Radiación/instrumentación , Radioisótopos de Estroncio/análisis , Monitoreo de Radiación/métodos
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