Metal alloys, matrix inclusions and manufacturing techniques of Moinhos de Golas collection (North Portugal): a study by micro-EDXRF, SEM–EDS, optical microscopy and X-ray radiography

"Article:820"A collection of 35 metallic artefacts comprising various typologies, some of which can be attributed to the Bronze Age and others to later periods, were studied to provide detailed information on elemental composition, manufacturing techniques and preservation state. Elemental analysis by micro-EDXRF and SEM–EDS was performed to investigate the use of different alloys and to study the presence of microstructural heterogeneities, as inclusions. X-ray radiography, optical microscopy and SEM–EDS were used to investigate manufacturing techniques and degradation features. Results showed that most of the artefacts were produced in a binary bronze alloy (Cu–Sn) with 10–15 wt% Sn and a low concentration of impurities. Other artefacts were produced in copper or in brass, the latest with varying contents of Zn, Sn and Pb. A variety of inclusions in the metal matrices were also found, some related to specific types of alloys, as (Cu–Ni)S2 in coppers, or ZnS in brasses. Microstructural observations revealed that the majority of the artefacts were subjected to cycles of thermomechanical processing after casting, being evident that among some artefacts different parts were subjected to distinct treatments. The radiographic images revealed structural heterogeneities related to local corrosion processes and fissures that seem to have developed in wear-tension zones, as in the handle of some daggers. Radiographic images were also useful to detect the use of different materials in one particular brass artefact, revealing the presence of a possible Cu–Sn solder.This work was funded by FEDER funds through the COMPETE 2020 Programme and National Funds through FCT— Fundação para a Ciência e a Tecnologia under the project UID/CTM/ 50025/2013 to CENIMAT/I3N. C2 TN/IST authors gratefully acknowledge the FCT support through the UID/Multi/04349/2013 project. EF acknowledges FCT for the grant SFRH/BPD/97360/2013. JF acknowledge FCT for the grant SFRH/BD/65143/2009. Part of this project has been done in the framework of the FCT project ENARDAS (PTDC/HISARQ/112983/2009).info:eu-repo/semantics/publishedVersio

Practical guidelines for rigor and reproducibility in preclinical and clinical studies on cardioprotection

The potential for ischemic preconditioning to reduce infarct size was first recognized more than 30 years ago. Despite extension of the concept to ischemic postconditioning and remote ischemic conditioning and literally thousands of experimental studies in various species and models which identified a multitude of signaling steps, so far there is only a single and very recent study, which has unequivocally translated cardioprotection to improved clinical outcome as the primary endpoint in patients. Many potential reasons for this disappointing lack of clinical translation of cardioprotection have been proposed, including lack of rigor and reproducibility in preclinical studies, and poor design and conduct of clinical trials. There is, however, universal agreement that robust preclinical data are a mandatory prerequisite to initiate a meaningful clinical trial. In this context, it is disconcerting that the CAESAR consortium (Consortium for preclinicAl assESsment of cARdioprotective therapies) in a highly standardized multi-center approach of preclinical studies identified only ischemic preconditioning, but not nitrite or sildenafil, when given as adjunct to reperfusion, to reduce infarct size. However, ischemic preconditioning—due to its very nature—can only be used in elective interventions, and not in acute myocardial infarction. Therefore, better strategies to identify robust and reproducible strategies of cardioprotection, which can subsequently be tested in clinical trials must be developed. We refer to the recent guidelines for experimental models of myocardial ischemia and infarction, and aim to provide now practical guidelines to ensure rigor and reproducibility in preclinical and clinical studies on cardioprotection. In line with the above guideline, we define rigor as standardized state-of-the-art design, conduct and reporting of a study, which is then a prerequisite for reproducibility, i.e. replication of results by another laboratory when performing exactly the same experiment

BioTIME 2.0: Expanding and Improving a Database of Biodiversity Time Series

Motivation Here, we make available a second version of the BioTIME database, which compiles records of abundance estimates for species in sample events of ecological assemblages through time. The updated version expands version 1.0 of the database by doubling the number of studies and includes substantial additional curation to the taxonomic accuracy of the records, as well as the metadata. Moreover, we now provide an R package (BioTIMEr) to facilitate use of the database. Main Types of Variables Included The database is composed of one main data table containing the abundance records and 11 metadata tables. The data are organised in a hierarchy of scales where 11,989,233 records are nested in 1,603,067 sample events, from 553,253 sampling locations, which are nested in 708 studies. A study is defined as a sampling methodology applied to an assemblage for a minimum of 2 years. Spatial Location and Grain Sampling locations in BioTIME are distributed across the planet, including marine, terrestrial and freshwater realms. Spatial grain size and extent vary across studies depending on sampling methodology. We recommend gridding of sampling locations into areas of consistent size. Time Period and Grain The earliest time series in BioTIME start in 1874, and the most recent records are from 2023. Temporal grain and duration vary across studies. We recommend doing sample-level rarefaction to ensure consistent sampling effort through time before calculating any diversity metric. Major Taxa and Level of Measurement The database includes any eukaryotic taxa, with a combined total of 56,400 taxa. Software Format csv and. SQL

Effects of land-use change on avian taxonomic, functional and phylogenetic diversity in a tropical montane rainforest

Aim Although land use change is a leading cause of biodiversity loss worldwide, there is scant information on the extent to which it has affected the structure and composition of bird communities in the Afrotropical region. This study aimed to quantify the effects of habitat transformation on taxonomic, functional and phylogenetic diversity in Afrotropical bird communities. Location Nyungwe landscape, a montane rainforest with adjoining farmland in south-west Rwanda. Methods Data on bird occurrence, abundance and functional traits were collected in 2017/18 using point counts. We also collected data on habitat and morphological traits for all bird species recorded. We quantified bird diversity using a range of metrics, including the inverse Simpson index, functional dispersion and the standardized effect size of mean nearest taxon distance. Results In comparison with primary forest areas, even low levels of land use change altered species composition and reduced species diversity. Although overall functional diversity and phylogenetic diversity were similar across land use types, we found a significant contraction of trophic and locomotory trait structures of bird communities in restored areas and cultivated areas, respectively. Soil moisture, elevation and lower vegetation height were major factors influencing taxonomic, functional and phylogenetic dimensions of bird communities, although their effects varied across these dimensions. Main conclusions The sensitivity of forest species to minor habitat disturbance emphasizes the value of conserving primary vegetation. Long-term conservation of bird communities in Afromontane ecosystems requires halting wide-scale destruction of primary forest, promoting vegetation heterogeneity in the ecological restoration of degraded habitats and adopting wildlife-friendly agricultural practices. Our results suggest that monitoring and conservation in these landscapes can be refined using taxonomic, functional and phylogenetic diversity metrics to provide complementary information about the current and likely future impacts of land use change

Historical Shipwrecks, Archaeometry of

Archaeometry can be broadly defined as the field where knowledge and analytical methods and techniques from natural and applied sciences enhance research carried out in archaeology and related disciplines. Close interaction between different specialists allows for systematic means of collecting, analyzing, and interpreting data to be applied and to shed light on archaeological questions. Until the 1990s, most studies were focused on answering inquiries related to dating, exploration, artifact function and use, material sources, and manufacture methods. From then on, research topics, scale of analysis, and materials considered have expanded. Likewise, some analytical means became more complex, while new ones were incorporated. Thus, it was possible to achieve a more comprehensive and detailed understanding of social knowledge, behaviors, technologies, environments, and interactions between them. Investigations within the field of maritime archaeology have not been left out of this trend. Advances made on exploration and survey, identification of materials and manufacturing methods, dating, provenance, site formation processes, and treatments for the stabilization of remains are notable. This essay explores areas that have lately shown a notable advance regarding the means used for recording shipwrecks, characterizing wooden and metal remains, and preserving in situ and conserving sites and finds.Fil: Ciarlo, Nicolás Carlos. Universidad de Buenos Aires. Facultad de Filosofía y Letras. Instituto de Arqueología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Combining Electrophoretic and Fluorescence Method for Screening Fine Structural Variations Among Lignin Model Polymers Differing in Monomer Composition

Due to the challenges of cell walls (biomass) and its applications in various new technologies, there is a need of rapid and reliable screening of fine variations in lignin structure. The in vitro synthesized lignin model polymers are good experimental system to relate lignin structure/properties with its applications. We used iso-electric focusing electrophoresis (IEF) and fluorescence spectroscopy for screening fine structural variations in lignin model polymers, synthesized from the three lignin monomers, coniferyl alcohol, ferulic acid and p-coumaric acid, mixed in various ratios. The results were related with the thermal behavior of the polymers, revealed by differential scanning calorimetry. Each polymer had characteristic IEF pattern that can be used as its fingerprint. On the basis of the number and intensity of particular bands, it is possible to detect fine differences between polymer patterns, associated with the charge distribution on the polymer fractions. The blue shift of the main fluorescence maximum position of the polymers increased in the same order as temperature of glass transition, i. e. (polymer from coniferyl alcohol)>[polymer from coniferyl alcohol and ferulic acid 9: 1 (w/w)>[(polymer from coniferyl alcohol, ferulic acid and p-coumaric acid 8: 1: 1)>(polymer from coniferyl alcohol and p-coumaric acid 9: 1). The results show that the proposed combination of the fluorescence method and IEF may be used to gain complementary information on fine structural differences among the polymers, and influence of the types and ratios of the monomers building the polymer structure