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The authors studied forty-three beautiful nose ornaments from the Moche tomb of the Lady of Cao, located in the north of Peru, which has been dated to be around 300–400 d.C. Of these items, thirty-nine are composed of a sheet of gold alloy joined together in various manners to a silver alloy sheet, which provides a strong contrast at their interface. Two nose ornaments are on gold alloy and two on silver alloy. These nose ornaments were studied using the following methods: (i) Energy-dispersive X-ray fluorescence (EDXRF); (ii) Transmission of monoenergetic X-rays (XRT) and (iii) X-ray Radiography (RAD). The conclusion, deduced from all applied methods, was that two sheets of gold and silver alloys were joined together with various methods, including gluing, mechanically joining, soldering, smelting with the aid of heating or using mercury to create an amalgam. It cannot be excluded that a few areas, visibly appearing as silver, were obtained by depletion silvering from the base Au-Cu-Ag alloy. By analyzing a fragment from the silver area of a nose ornament and by studying a few other nose ornaments from the tomb of the Lady of Cao in situ, G. Ingo and co-workers concluded that a unique sheet of three-component alloy (Ag-Cu-Au), whichemployed and transformed the surface of the objects to appear to be gold and silver by depletion gilding and silvering. [ABSTRACT FROM AUTHOR]

The Standard Thermal Neutron Flux Unit, TNF2, in (LNMRI/IRD)(1,   2), was built for neutron detector and survey meter calibrations. The facility's fluence is achieved by moderation of four 241Am-Be with a graphite core and paraffin/graphite blocks surrounding it. Due to the small channel dimensions, it is impossible to calibrate personal dosemeters and survey meters for thermal neutrons. A polyethylene filter construction was carried out to allow the external irradiation of personal dosemeters and neutron survey meters. The polyethylene filter was constructed with 29 stacked discs with diameters ranging from 5 to 34 cm. Different thicknesses were simulated to provide the desired effect. This new irradiation configuration was also experimentally tested and compared with simulation results with MCNPX(3). [ABSTRACT FROM AUTHOR]

An X-ray Transmission Microtomography (CT) system combined with an X-ray Fluorescence Microtomography (XRFCT) system was implemented in the Brazilian Synchrotron Light Laboratory (LNLS), Campinas, Brazil. The main of this work is to determine the elemental distribution map in reference samples and breast tissue samples in order to verify the concentration of some elements correlated with characteristics and pathology of each tissue observed by the transmission CT. The experiments were performed at the X-Ray Fluorescence beamline (D09B-XRF) of the Brazilian Synchrotron Light Laboratory, Campinas, Brazil. A quasi-monochromatic beam produced by a multilayer monochromator was used as an incident beam. The sample was placed on a high precision goniometer and translation stages that allow rotating as well as translating it perpendicularly to the beam. The fluorescence photons were collected with an energy dispersive HPGe detector placed at 90[degrees] to the incident beam, while transmitted photons were detected with a fast Na(TI) scintillation counter placed behind the sample on the beam direction. The CT images were reconstructed using a filtered-back projection algorithm and the XRFCT were reconstructed using a filtered-back projection algorithm with absorption corrections. Index Terms--Biological tissues, fluorescence, synchrotron radiation, tomography.

Pasteurization is a thermal treatment applied to the milk used in human milk banks so as to provoke the thermic inactivation of pathogenic micro-organisms, with the aim of avoiding contamination of milk that will be offered to new-born infants in clinical conditions very often demanding special care. The literature has very little data available relating to the effect of pasteurization on the concentration of oligo-elements in human milk. The objective of this study was to evaluate the effect of pasteurization on the concentrations of iron (Fe), copper (Cu) and zinc (Zn) in the colostrum of mothers of pre-term (PT) and term (T) infants. Samples were collected from the day of birth to the seventh day after birth. The oligo-elements were analyzed using the total reflection X-ray fluorescence technique with synchrotron radiation. The following results of Fe, Cu and Zn (means [+ or -] SD) were obtained for the PT and T colostrum samples, non-pasteurized and pasteurized, respectively: PT: 1.96 [+ or -] 0.73 mg/l Fe/ 1.71 [+ or -] 0.70 mg/l Fe, 0.67 [+ or -] 0.28 mg/l Cu/0.64 [+ or -] 0.28 mg/l Cu, 5.55 [+ or -] 2.71 mg/l Zn/5.39 [+ or -] 2.73 mg/l Zn; T: 1.71 [+ or -] 1.01 mg/l Fe/1.46 [+ or -] 0.99 mg/l Fe, 0.54 [+ or -] 0.29 mg/l Cu/0.49 [+ or -] 0.19 mg/l Cu, 6.97 [+ or -] 2.82 mg/l Zn/6.75 [+ or -] 2.62 mg/l Zn. There was a significant reduction in the levels of Fe, Cu and Zn in the samples of pasteurized colostrum. These results suggest that, despite the observance of a diminution in the levels of Fe, Cu and Zn in the samples of pasteurized colostrum, the values fell within the acceptable range for the specific nutritional needs of new-born infants during this period of lactation.

The influence of the casing and liquid inside the borehole in neutron porosity tool response is analyzed. For this, MCNPX simulation of neutron tool inside of a slim borehole was performed. The results showed that the presence of PVC casing and liquid inside the borehole reduces the tool response in about 73% for low porosities, and 90% for high porosities. [ABSTRACT FROM AUTHOR]

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