Characterization of a Unique Nuragic Bronze Navicella with a Combination of X-ray Fluorescence Spectrometry and Monte Carlo Simulation.

This paper describes the results obtained from an archaeometric study of a bronze Nuragic small boat model (Sardinia, Italy) dating from the Early Iron Age (presumably 9th-7th centuries BC). The artifact comes from an unknown location in Sardinia and is one of the objects that came to the Museum of Turin in the 19th century. This model is of particular interest as it is a unique Nuragic boat model containing a human figure among its decorations. The artifact is kept in the collection of the Royal Museum of Turin (Italy) and is a typical example of Sardinian manufacture from the Early Iron Age. This study was carried out using a combination of non-invasive techniques with energy dispersive X-ray fluorescence spectrometry (ED-XRF) integrated with Monte Carlo (MC) simulations and Raman spectroscopy, which allowed the characterization of the alloy of the artifact.

Nuragic Working Tools Characterization with Corrosion Layer Determinations.

From the availability of metals to the technology and tools needed to transform them, roughly every civilization in the Mediterranean basin has a metalsmith story. Many of the objects produced by them share a few peculiar characteristics, usages, or even shapes. In this scenario, a class of objects that can be clustered by their usage, i.e., working tools, stands out from the crowd. For this study, a set of working tools from the Nuragic civilization (Sardinia, Italy) was researched with a non-destructive technique: X-ray Fluorescence (XRF). A quantification of the chemical species present in their alloy was obtained with the use of Monte Carlo simulations. The XRMC package, used for the simulations, managed for the first time to reproduce very complex corrosion layers and to thoroughly characterize them from a chemical perspective. The obtained results were discussed and compared to other results reported in the literature.

The Strange Case of the Nuragic Offerers Bronze Statuettes: A Multi-Analytical Study.

The Nuragic civilization (Sardinia, Italy, XVIII-VIII B.C) developed a flourishing bronze metallurgy with strong connections with other civilizations from the Mediterranean basin. Within the large bronze production, there are some peculiar representations of human figures, known in the archaeological environment of Sardinia as bronzetti, depicting warriors, priests, and offerers. In this paper, an interesting couple of Nuragic statuettes representing offerers, one from the Pigorini Museum in Rome and another from the Musei Reali in Turin, were analyzed. They have been investigated with X-ray fluorescence integrated with Monte Carlo simulations (XRF-MC). The combined methodology provides more accurate results, ranging from the structural characterization to the identification of the corrosion layers to the estimation of the composition of the alloy of the artifact. One of the most striking results regards the heads of the offerers: both heads are covered with a thick iron-based layer, even though the whole artifacts are made of a copper alloy. To understand the reason behind this peculiar corrosion patina, several hypotheses have been considered, including the possibility that these iron mineralizations are the consequence of an ancient superficial treatment, intending to confer a chromatic effect on the figurine's head.

Characterisation of Alloy Composition of Protohistoric Small Boat Models from Sardinia (Italy).

The Sardinian protohistoric civilisation (Final Bronze Age and the Early Iron Age) has greatly contributed to the development of metallurgy in the Mediterranean area by producing a large number of bronze artefacts. Among them, small boat models (so-called "navicelle") represent one of the most characteristic objects from the Sardinian Protohistoric civilisation. This work is an attempt to classify these boats on the basis of their alloy composition, provenience, and morphology. Due to the impossibility of removing the boats from the museum, alloys were characterised using energy-dispersive X-ray fluorescence spectrometry and Monte Carlo simulations. Fifteen boats were analyzed. Obtained results were compared to other performed analyses in the last few decades with different techniques and reported in the literature. Analyses allow for characterising both the bulk composition of ternary alloy Cu-Sn-Pb and patina thickness, offering useful information about their conservation status and the technological achievements of Sardinian craftsmen, while also providing information on smelting temperatures and casting techniques.

Modular MA-XRF Scanner Development in the Multi-Analytical Characterisation of a 17th Century Azulejo from Portugal.

A modular X-ray scanning system was developed, to fill in the gap between portable instruments (with a limited analytical area) and mobile instruments (with large analytical areas, and sometimes bulky and difficult to transport). The scanner has been compared to a commercial tabletop instrument, by analysing a Portuguese tile (azulejo) from the 17th century. Complementary techniques were used to achieve a throughout characterisation of the sample in a complete non-destructive approach. The complexity of the acquired X-ray fluorescence (XRF) spectra, due to inherent sample stratigraphy, has been resolved using Monte Carlo simulations, and Raman spectroscopy, as the most suitable technique to complement the analysis of azulejos colours, yielding satisfactory results. The colouring agents were identified as cobalt blue and a Zn-modified Naples-yellow. The stratigraphy of the area under study was partially modelled with Monte Carlo simulations. The scanners performance has been compared by evaluating the images outputs and the global spectrum.

Differential X-Ray Attenuation in MA-XRF Analysis for a Non-invasive Determination of Gilding Thickness.

When investigating gilded artifacts or works of art, the determination of the gilding thickness plays a significant role in establishing restoration protocols or conservation strategies. Unfortunately, this is done by cross-sectioning the object, a destructive approach not always feasible. A non-destructive alternative, based on the differential attenuation of fluorescence radiation from the sample, has been developed in the past years, but due to the intrinsic random nature of X-rays, the study of single or few spots of an objects surface may yield biased information. Furthermore, considering the effects of both porosity and sample inhomogeneities is a practice commonly overlooked, which may introduce systematic errors. In order to overcome these matters, here we propose the extrapolation of the differential-attenuation method from single-spot X-ray fluorescence (XRF) measurements to macro-XRF (MA-XRF) scanning. In this work, an innovative algorithm was developed for evaluating the large amount of data coming from MA-XRF datasets and evaluate the thickness of a given overlapping layer over an area. This approach was adopted to study a gilded copper-based buckle from the sixteenth to seventeenth century found in Rome. The gilded object under investigation was also studied by other analytical techniques including scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS). Previous results obtained from SEM-EDS were used to confront the data obtained with the proposed methodology and validate it. MA-XRF elemental distribution maps were fundamental in identifying and choosing sampling areas to calculate the thickness of the gilding layer, avoiding lead islands present in the sample that could negatively influence the results. Albeit the large relative standard deviation, the mean thickness values fell within those found in literature and those obtained from previous studies with SEM-EDS. Surface fissure has been found to deeply affect the results obtained, an aspect that is often disregarded.

Delegação de funções ao pessoal auxiliar odontológico pelos cirurgiões-dentistas da cidade de Campina Grande - PB / Function delegation to dental auxiliary personnel by dentists in the city of Campina Grande - PB

Este estudo avaliou a utilização do pessoal auxiliar odontológico pelos cirurgiões-dentistas com atuação em consultórios odontológicos privados no município de Campina Grande-PB. A amostra foi constituída por 67 profissionais selecionados dentre aqueles com registro no Conselho Regional de Odontologia - PB. Para a coleta dos dados, foi elaborado um questionário específico que envolvia as atividades desenvolvidas pelos auxiliares. Dentre os principais resultados, verificou-se que 71,7 por cento (48) dos profissionais utilizam pessoal auxiliar. Contudo, apenas 39,6 por cento (19) dos auxiliares possuem registro no Conselho Regional. Dentre as tarefas realizadas, a marcação de consultas foi a mais delegada (95,8 por cento), seguida da organização dos arquivos e fichários (89,5 por cento). Os resultados permitem concluir que há uma subutilização do pessoal auxiliar pelos dentistas e a eficiência da prática odontológica poderia ser maior se esses auxiliares fossem utilizados adequadamente.

O prolapso de valvula mitral e suas complicacoes: revisao de literatura / The mitral value prolapse and its complications: literature review

A prevalencia do prolapso de valvula mitral (PVM) e variavel conforme metodos de diagnostico empregados e populacoes estudadas, variando de 1,4 por cento em criancas ate 17 por cento em populacao jovem, com predominio do sexo feminino. Existe relacao de PVM com outras anomalias, incluindo disturbios anatomicos e variadas doencas, por exemplo: hipertireoidismo. A patogenese e discutida, mas as degeneracoes mixomatosas sao os eventos primarios. As complicacoes, pouco frequentes, incluem 4.000 mortes subitas, 1.150 casos de endocardites e 4.000 cirurgias de valvula mitral por severa regurgitacao mitral por ano nos EUA, em uma populacao de cerca de 7 milhoes de pessoas com a desordem valvular. Existem grupos de risco para severa regurgitacao mitral (RM) e endocardite infecciosa (I), morte subita e ruptura de cordoalha tendinea, sendo que os fatores de risco para cada complicacao estao incluidos entre os seguintes dados: homens, mais de 45 anos e sopro sistolico de regurgitacao.