Non-destructive characterization of archeological Cu-based artifacts from the early metallurgy of southern Portugal

In this study, Monte Carlo (MC) simulations combined with energy dispersive X-ray fluorescence (EDXRF) spectroscopy have been used to characterize non-destructively a collection of Cu-based artifacts recovered from two archeological sites in southern Portugal: (a) the Chalcolithic E.T.A.R. site of Vila Nova de Mil Fontes and (b) the Middle Bronze Age site of Quinta do Estácio 6. The metal artifacts show a multilayered structure made up of three distinct layers: (a) brownish carbonate soil-derived crust, (b) green oxidized corrosion patina, and (c) bulk metal. In order to assess the reliability of the EDXRF-based Monte Carlo simulations to reproduce the composition of the alloy substrate in archeological bronze artifacts without the need to previously remove the superficial corrosion and soil derived patinas, EDXRF analysis together with scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) was also performed on cleaned and patina-/crust-coated areas of the artifacts. Characterization of the mineralogical composition of the corrosion products in the surface patinas was further determined by means of X-ray diffraction (XRD). Results suggest that the adopted EDXRF/Monte Carlo protocol may represent a safe and fast analytical approach in the quantitative characterization of the bulk chemical composition of Cu-based metal artifacts even in the presence of fairly thick corrosion patinas and/or soil-derived encrustations at the surface of the archeological objects

Computer vision-based wood identification: a review

Wood identification is an important tool in many areas, from biology to cultural heritage. In the fight against illegal logging, it has a more necessary and impactful application. Identifying a wood sample to genus or species level is difficult, expensive and time-consuming, even when using the most recent methods, resulting in a growing need for a readily accessible and field-applicable method for scientific wood identification. Providing fast results and ease of use, computer vision-based technology is an economically accessible option currently applied to meet the demand for automated wood identification. However, despite the promising characteristics and accurate results of this method, it remains a niche research area in wood sciences and is little known in other fields of application such as cultural heritage. To share the results and applicability of computer vision-based wood identification, this paper reviews the most frequently cited and relevant published research based on computer vision and machine learning techniques, aiming to facilitate and promote the use of this technology in research and encourage its application among end-users who need quick and reliable results.info:eu-repo/semantics/publishedVersio

Monitoring glucose, calcium, and magnesium levels in saliva as a non-invasive analysis by sequential injection multiparametric determination

info:eu-repo/semantics/publishedVersio

A Framework Design for Information Management in Heritage Science Laboratories

The dataflow in any scientific research laboratory is continuous and considerable even in analytical niches such as heritage science laboratories. This article discusses advantages of using a Laboratory Information Management System (LIMS) for organising and systematising research in an interdisciplinary analytical laboratory. LIMS solutions are proven to be effective in managing laboratories, organising their daily management tasks, improving work conditions and increasing productivity, managing equipment and resources, and managing and safeguarding scientific data. LIMS software is commercially available since the 1990s with over a hundred software packages intended either for general or specific purposes. However, the ones currently available do not fulfil all the requirements for heritage science or are over-the-top, complex, one-fits-all standard solutions. The system here proposed was developed for a heritage science laboratory, considering its unique requirements, having as a case study the HERCULES Lab, from the University of Évora (Portugal). This article documents our approach based on the analysis of the unique requirements for the lab resulting in a proposal of a custom user-centred web-based system. For this, we discuss in detail the workflow, and the required system architecture. We conclude that although it is a small niche market for major manufacturers to dwell on, a custom LIMS is of the utmost importance for the current management of heritage science laboratories across the globe

Application of ultrasonic pulse velocity for the condition assessment of plaster sculptures: a preliminary study

Ultrasonic pulse velocity (UPV) is generally used in Civil Engineering as an in-situ and non-destructive methodology to assess the condition of construction materials. Given the fact that non-contemporary sculpture was traditionally made with similar materials – stone, wood, clay or plaster – a hypothesis arose regarding the possible contribution of UPV for the conservation assessment of sculptures with stone-based materials. Plaster is a fragile material, very susceptible to internal and external fractures, alterations and losses. Museum sculptures cannot be moved to a laboratory, due to conservation protocols and therefore portable UPV could, in theory, play an important role in assessing these artistic structures in-situ. There are scarce references to such a methodology, and its implementation implied a partnership with Soares dos Reis National Museum (Porto, Portugal) for an experimental approach to three plaster sculptures made by A. Soares dos Reis: “St. Joseph”, “St. Joachim” (both made in 1880) and “Narcissus” (1881). The aim of this study was to assess if portable UPV could help to detect superficial and internal damages and differences between the original plaster and added materials. UPV uses two transducers: a very high frequency pulse emitter (54 kHz or 150 kHz, depending on the type of transducer) and a receiver which measures the transit time, or the Time-of-Flight (ToF), between the transducers. Depending on the relative orientation of the transducers, the measurements are said to be direct, indirect or semi-direct. The distance between the transducers (the shortest path) divided by the ToF gives the velocity of propagation of longitudinal mechanical waves in the material, for the frequency used. If the shortest effective path does not match the measurement of the distance between the transducers, the time of flight is longer than it should be. Therefore, obtaining a lower velocity than the expected for a given material allows to identify an internal defect, a different material or alteration. An excessively high attenuation can also occur, depending on the extension of the wave path, or an interruption of the signal transmission due to the existence of a fault or due to the signal propagation in a material whose acoustic impedance is very different from the original material. When this happens, the signal may be lost. Before using UPV in situ, laboratory tests were carried out with plaster prototypes and different types of measurements. A fundamental part of the testing process involved the experimentation of flexible materials that could play the role of interface between the transducers and the sculptures. This is of the most importance in order to guarantee that the methodology is entirely safe concerning conservation standards.This work is part of a larger research project dedicated to the study of Soares dos Reis sculpture (GEO-SR: multidisciplinary approach to alteration, alterability and conservation of Soares dos Reis’ geomaterial sculpture – breaking boundaries in museum paradigms and creating value in changing societies through culture - PTDC/ART-OUT/31304/2017/POCI-01-0145-FEDER-031304)

From sampling to collection: the sample collection from Universidade Católica Portuguesa

info:eu-repo/semantics/publishedVersio

Exploring portable ultrasonic pulse velocity avails in the conservation assessment of plaster sculptures in museum environment

Ultrasonic pulse velocity (UPV) is generally used in Civil Engineering as an in situ and non-destructive methodology to assess the condition of construction materials. Given the fact that non-contemporary sculpture was traditionally made with similar materials – stone, wood, clay or plaster – a hypothesis arose regarding the possible contribution of UPV for the conservation assessment of sculptures with stone-based materials. Plaster is a fragile material, very susceptible to internal and external fractures, alterations and losses. Museum sculptures cannot be moved to a laboratory, due to conservation protocols and therefore portable UPV could, in theory, play an important role in assessing these artistic structures in situ. There are scarce references to such a methodology, and its implementation implied a partnership with Soares dos Reis National Museum (Porto, Portugal) for an experimental approach to three plaster sculptures made by A. Soares dos Reis: “St. Joseph”, “St. Joachim” (both made in 1880) and “Narcissus” (1881). The aim of this study was to assess if portable UPV could help to detect superficial and internal damages and differences between the original plaster and added materials

Bituminous waterproofing mortar applied on masonry walls of 19th and 20th century buildings in Porto: an analytical study in the context of urban building rehabilitation

Bituminous mortars characterize the traditional buildings of the city of Porto and northern Portugal, especially those built between the end of the 19th century and the first decades of the 20th century. This article aims to determine the composition of this bituminous mortar through an analytical study by micro-FTIR and Py-GS/MS, and to assert experimentally its effectiveness as a waterproofing material though a series of tests including capillary tests, saturation content and water permeability. The present study is still a starting point for a more in-depth study on this subject, but the present investigation constitutes a further step in the characterisation of the constitution and function of bituminous mortar

Mapping lacunae for retouching paintings with computer graphics software

The objective of this paper is to present a workflow procedure to support the graphic recording of the operations performed during the retouching process involved in paintings. In this particular context, an orthophotography of a portrait painted on canvas from a university museum collection was used in Blender, a free and open-source 3D creation software suite. Blender uses an important metric coordination value, provided by the 3D workspace software that allows the areal characterization and numeric identification of each surface loss. The step-by-step procedure adopted to document and map lacunae in this artwork for subsequent retouching, is described.info:eu-repo/semantics/submittedVersio

Burnout and occupational stress in the medical residents of oncology, hematology and radiotherapy: a prevalence and predictors study in Portugal

Burnout is a professional syndrome associated with stress caused by overwork. Our aim was to calculate the prevalence of burnout and stress on medical residents of Oncology, Haematology and Radiotherapy in Portugal, as well as to determine predictors of burnout and stress. An anonymous questionnaire was applied (n = 118). Statistical analysis consisted of a descriptive and inferential analysis. The prevalence of burnout and stress was calculated to be 45.2 and 50%, respectively. The dimensions that generated higher levels of stress were ‘dealing with patients’ and ‘overwork’. Burnout was directly related with stress dimension ‘overwork’. The prevalence of burnout in Portuguese oncological residents is high as in other European countries and in the U.S. Therefore, interventional strategies can be designed.info:eu-repo/semantics/publishedVersio