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X-radiography using the bremsstrahlung of a commercial broad spectrum X-ray source was used to quantify the differences and relationships between complex samples of unknown composition. The samples examined were painted and glazed ceramic mugs. The resulting pseudo-signatures were grey-level transmission spectra which can be usefully compared over a range of acceleration potential settings from 40 to 95 kV, taken at 1 kV intervals. These data are extracted from stacks of registered field-flattened X-ray images. It is shown that it is possible to differentiate between transmission spectra of the samples by concentrating mainly on the paint layers. [ABSTRACT FROM AUTHOR]

This article reports on the employment of X-radiography using the bremsstrahlung of a commercial broad-spectrum X-ray source to quantify the differences and relationships between complex materials of unknown composition. The materials examined were metallic powders embedded in a carrier paste. The resulting pseudo-signatures are transmission spectra over a range from 15 to 75 kV taken at 1 kV intervals, which were extracted from stacks of registered, field-flattened images. It is shown that it is possible to quantify differences between transmission spectra in order to differentiate between metallic powders used to impregnate the carrier paste. [ABSTRACT FROM AUTHOR]

This study was carried out to investigate the effects of physical activity on cortical bone of the radius in a population of prepubertal girls. Forty-nine healthy girls, 17 actives (10.62 ± 1.56 years) and 32 controls (9.84 ± 1.23 years) participated in this study. The active group was involved in gymnastics, judo, and dance on average 7.76 ± 3.94h/week. Bone mineral content (BMC) and density (BMD) were performed at the distal third of the non-dominant radius using DXA. The lean mass of the non-dominant forearm was derived from the total body analysis performed with DXA. In order to obtain bone cortical thickness, standard radiographs of the non-dominant radius were scanned and computed using a software program based on radiogrammetry. BMD and BMC values were higher in actives than in controls. Cortical thickness at the ulnar side correlated significantly with all the anthropometric and densitometric values as well as the duration of training. In addition, cortical thickness at the ulnar side was significantly higher in the actives compared to the controls. After adjustment for the duration of training per week, cortical thickness of the ulnar side did not differ any more between actives and controls. The same observation was obtained after adjustment for the forearm lean mass. In our active population, physical practice seemed to have induced greater BMC and higher cortical thickness than those observed in the sedentary. [ABSTRACT FROM AUTHOR]

Thioglycolic acid-functionalized ZnSe quantum dots (QDs) as a colorimetric nanoprobe were prepared and applied to the determination of cobalt(II) and iron(III). Test strips were obtained by a dipping-drying process. On exposure to Co(II), they undergo a color change from white to brown, and on exposure to Fe(III) from white to pink. The limits of detection (LOD) are 2.6 mg L−1 for Co(II) and 2.2 mg L−1 for Fe(III). Test strips introduce a low-cost, portable, rapid and convenient tool for determination of Co(II) and Fe(III). In addition, two other analytical methods have been studied for detection of Co(II) and Fe(III) at low concentration. The first is UV-vis spectrometry which has a LOD as low as 0.14 mg L−1 for Co(II) (at 412 nm) and 0.12 mg L−1 for Fe(III) (at 400 nm). The second is dynamic light scattering (DLS) with a LOD of 3.0 μg L−1 for Co(II) and 2.5 μg L−1 for Fe(III). [ABSTRACT FROM AUTHOR]