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Food irradiation is a safe and effective preservation technique to eliminate insects and parasites and reduce disease-causing microorganisms. The process helps to inhibit sprouting and delay ripening, prolonging the shelf-life of fresh fruits and vegetables. Nevertheless, among a great fraction of Brazilian population, there is still great misunderstanding about the peaceful applications of nuclear science. Most often the media and social networks tend to associate radiation to nuclear weapons and major accidents. Misinformation and common wrong beliefs confuse public’s perceptions: consumers seem to misunderstand the difference between irradiated food and radioactive food and the general public has major concerns about the negative health effects and environmental contamination. This paper presents some considerations about consumers´ perceptions of irradiated food, as well as the need of improving science communication. Society´s judgments and decision making are directly linked to perceived benefits and risks. The scientific community must build new bridges between nuclear science and the general public, offering a wider perspective on the benefits and risks resulting from ionizing radiation in everyday life.

In order to establish a Radiation Protection Plan or a Radiation Emergency Plan, Brazilian facilities should take into account all procedures based on national and international guidelines and recommendations. This information can be found in several documents published by different organizations over the past decades: the International Commission on Radiological Protection (ICRP), International Atomic Energy Agency (IAEA) and Comissão Nacional de Energia Nuclear (CNEN). Therefore, this project aims the informatization of the radiological protection programs in a single system in order to offer unified programs and inter-related information in Portuguese, providing Brazilian facilities a complete repository for research, consultation and information, combining computer technology and radiological protection in order to enhance the best benefits from information technology. This research work includes programs about: (1) Monitoring of Workplace (Monitoring for External Radiation, Monitoring for Surface Contamination, Monitoring for Air Contamination) and (2) Individual Monitoring (Monitoring of External Exposure and Monitoring of Internal Exposure, Monitoring for Skin and Clothing). WEB platform tools and functionalities were developed according to target public needs, regarding new possibilities of media, mobile access, and information sharing. The servers processing power added to the technology of relational databases allow to integrate information from different sources, enabling complex queries with reduced response time. Moreover, taking into account this is a pioneer project with the prospect of long-term use, the challenge involves the combination of multiple computer technologies that allows a robust, effective and flexible system, which can be easily adapted to future technological innovations.

The Desana treasure is a remarkable assemblage of items made of gold, silver, gemstones and glasses found in north-western Italy. Most scholars agree on the fact that the core of the treasure might have belonged to a single deposit resulted from a long period of selection, accumulation and use. The treasure testifies to the evolution of goldsmiths' art in Ostrogothic Italy and represents an extraordinary material trace of the Italian elites of the 5th–6th centuries. The Desana treasure was investigated with non-invasive instrumental analytical techniques, namely optical microscopy, UV-visible diffuse reflectance spectrophotometry with optical fibres and X-ray fluorescence spectrometry in order to record the chemical features of gemstones, coloured glasses and precious metals employed to produce the items. As for the gemstones, besides identifying typologies, data suggested India as the source for a sapphire pendant and for most of the garnets, whereas the emeralds may belong to different sources, among which Pakistan, India and Egypt. The investigation revealed the colouring agents and compositional features of the glasses, and the composition of the gold alloys. The results of the investigation highlight that the raw materials used by Late Antique Italian goldsmiths did not differ significantly from other neighbouring European and Mediterranean regions, although the garnets show some differences if compared with coeval jewels recorded north of the Alps. The dataset produced in this work complements the stylistic approach for the study of these amazing traces of the past and deepens our knowledge on the role of the Italian "Ostrogothic" jewellery in the frame of the coeval Mediterranean, Central European and Northern Pontic metalwork traditions. [ABSTRACT FROM AUTHOR]

X-ray fluorescence spectroscopy is a non-destructive technique employed for elemental analysis of a wide range of materials. Its advantages are especially valued in archaeometry, where portable instruments are available. Considering ancient glass, such instruments allow for the detection of some major, minor, and trace elements linked to the deliberate addition of specific components or to impurities in the raw materials of the glass batch. Besides some undoubted advantages, portable XRF (p-XRF) has some limitations that are addressed in this study. The performance assessment of four different p-XRF units and the reconciling of their output were conducted. The results show the limitations in cross-referencing the data obtained from each unit and suggest procedures to overcome the issues. The p-XRF units were tested on the set of Corning reference glasses and on a small set of archaeological glasses with known composition. The compatibility of the output was assessed using multivariate statistical tools. Such a workflow allows us to consider data from multiple sources in the same frame of reference. [ABSTRACT FROM AUTHOR]

The identification of gemstones is an important topic in the field of cultural heritage, given their enormous value. Particularly, the most important precious stones, namely diamond, emerald, ruby and sapphire, are frequently subjected to counterfeit by substitution with objects of lesser value with similar appearance, colour or shape. While a gemmologist is able to recognise a counterfeit in most instances, more generally, it is not easy to do this without resorting to instrumental methods. In this work, the use of UV-visible diffuse reflectance spectrophotometry with optic fibres (FORS) is proposed as a fast and easy method for the preliminary identification of gemstones, alternative to the classical methods used by gemmologists or to Raman spectroscopy, which is by far the instrumental method with the best diagnostic potential, but it cannot be used in situations of problematic geometric hindrance. The possibilities and the limitations given by the FORS technique are critically discussed together with the spectral features of the most important gemstones. Finally, the application of chemometric pattern recognition methods is described for the treatment of large sets of spectral data deriving from gemstones identification. [ABSTRACT FROM AUTHOR]

This paper has discussed the guidelines included in the documents of the International Commission on Radiological Protection (ICRP) on radiation protection applicable to aircraft and crew, and this is a brief report of the evolution of studies in this field of activity, as well as the regulations and recommendations already adopted by member countries of the European Union, Canada, and the United States of America. Some peculiarities of the Brazilian airspace and legislation applicable to the work with ionizing radiation are also presented, discussing the general aspects of radiological protection applicable to aircraft crew in Brazil.

The analysis explains the effects of the nanoparticle doping on electrical properties of [MgB.sub.2] bulks and wires, which are obtained by the reactive Mg liquid infiltration (RLI) technique. It is found that the addition of SiC nanoparticles improves the irreversibility, as well as the upper current field of the wires.

A number of debates exist in Africa, due to the HIV epidemics, on whether institutionalized compared with community-based care provide optimum management of infected children. Patterns of morbidity and mortality among HIV-1-infected children residing at an orphanage in Nairobi are characterized.

An illuminated Book of Hours (in use in Chalon-sur-Saône) currently owned by the Museo Civico di Arte Antica and displayed in the prestigious Palazzo Madama in Torino (Italy) was investigated by means of optical microscopy, fibre optic reflectance spectroscopy, fibre optic molecular fluorimetry, X-ray fluorescence spectrometry and Raman spectroscopy. The aim of the scientific survey was to expand the knowledge of the manuscript itself and on the materials and techniques employed by Antoine the Lonhy, the versatile itinerant artist who decorated the book in the 15th century. The focus was to reveal the original colourants and to investigate the pigments used in rough retouches which were visible in some of the miniatures. The investigation was carried out in situ by portable instruments according to a non-invasive analytical sequence previously developed. It was evident that the use of different pigments by the master was ruled, at least partially, by a hierarchical scheme in which more precious materials were linked to the most important characters or details in the painted scene. [ABSTRACT FROM AUTHOR]

We have investigated the modifications induced in the high-Tc superconductor Bi2Sr2CaCu2O8+δ (Bi-2212) by X-ray nanopatterning, which is an innovative, photoresist-free, direct-writing approach recently used to fabricate proof-of-concept electrical devices [Truccato et al., Nano Lett., 2016, 16, 1669]. By means of combined synchrotron microdiffraction and electrical transport measurements carried out on the same Bi-2212 microcrystal, we show that hard X-ray irradiation with fluences of the order of 1012 J m−2, corresponding to doses of the order of 1013 Gy, induces crystal fragmentation into multiple subdomains and decreases the carrier density of the system. We ascertain that the synergistic action of grain boundaries and of oxygen removal from the material dramatically changes the properties of Bi-2212 both in the normal and in the superconducting state. This special feature of X-ray nanopatterning introduces an opportunity that could be exploited to finely tune material structural defects according to the desired properties. [ABSTRACT FROM AUTHOR]