Dry sliding wear behaviour of Ti-TiB-TiNx in-situ composite synthesised by reactive hot pressing

Ti and its alloys are attractive materials for a variety of fields; however, a major problem of Ti and its alloys is their poor wear resistance. It is known that reinforcing Ti with hard ceramic phases can substantially improve the wear resistance. Thus, Ti-TiB-TiNx in-situ metal matrix composites were synthesised by reactive hot pressing utilising Ti/BN powder blends with 23:1 Ti:BN weight ratio. Ball-on-plate reciprocating dry sliding wear tests were performed against a 10 mm of alumina ball under 10 N normal load, at a frequency of 1 Hz, and with the total stroke length of 3 mm during 1,800 s. Results showed that the total wear volume loss was significantly decreased on the composite (11.4 +/- 2.0 x 10(-3) mm(3)) as compared to the unreinforced Ti (40.9 +/- 4.2 x 10(-3) mm(3)) due to the strengthening effect of the in-situ reinforcing phases.This study was supported by The Calouste Gulbenkian Foundation through Programa de Mobilidade Academica para Professores and Portuguese Foundation for Science and Technology (FCT-Portugal), under the project EXCL/EMS-TEC/0460/2012. The authors also would like to thank Prof. Amilcar Ramalho (Universidade de Coimbra) for the provision of profilometry facilities.info:eu-repo/semantics/publishedVersio

Unraveling site fidelity and residency patterns of sperm whales in the insular oceanic waters of Macaronesia

Knowledge of the distribution and residency of pelagic marine megafauna, particularly deep-diving species, is scarce due to their high mobility over difficult-to-access oceanic areas and long periods underwater. However, the threatened status of many of these species, such as the sperm whale Physeter macrocephalus, increases the need to obtain quantitative data to support conservation measures. In the warm temperate waters of Macaronesia (Eastern North Atlantic), sperm whales occur year-round in a set of island systems (the Azores, Madeira, and the Canaries), mainly in social groups of females and juveniles with the occasional visits of mature males. Although it is known that they perform inter-archipelago movements, information on site fidelity and residency times is still scarce. Here, based on photographic-identification data, site fidelity and residency times of sperm whales were estimated for subareas of the Azores and the Madeira archipelagos, with a preliminary assessment for a subarea of the Canaries. The Azores and Madeira subareas presented similar proportions of individuals with recaptures (~25%), mainly inter-annual, while in the subarea of the Canaries, only <10% of the individuals were recaptured. Standardized Site Fidelity Indexes showed very low values (<0.01) for both the Azores and Madeira subareas. Lagged identification rates based on models including emigration and reimmigration estimated that an average of 44.8 individuals (SE=4.9) spent 12.9 days (SE=1.5) in the Azores before leaving for 99.1 days (SE=12.5), while 8.4 individuals (SE=16.1) spent 0.8 day (SE=6.6) in Madeira before leaving for 8.6 days (SE=6.9), with a very low mortality rate. This study i) indicates a degree of residency of about ¼ of the identified individuals for the Azores and Madeira subareas and ii) supports that these oceanic archipelagos constitute an important habitat for a Vulnerable species in the Atlantic. Moreover, it also highlights the importance of combining data from opportunistic and dedicated surveys and joint national and international efforts toward the conservation of marine megafauna.This study had the support of FCT through the strategic project UIDB/04292/2020 awarded to MARE and through the project LA/P/0069/2020 granted to the Associate Laboratory ARNET. It was also supported through the strategic project M1420-01-0142-FEDER-000001 for the Oceanic Observatory of Madeira and from Oceanário de Lisboa and Oceano Azul Foundation through Whale Tales Project (ODL/2019/003). RF was supported by the FCT grant SFRH/BD/147225/2019, MF by the MAC2/1.1a/385 in the framework of INTERTAGUA (MAC INTERREG 2014-2020), AD by ARDITI throughout the project M1420-09-5369-FSE-000002 and FA by the FCT project UIDP/04292/2020 granted to MARE.info:eu-repo/semantics/publishedVersio

Modeling Fine-Scale Cetaceans’ Distributions in Oceanic Islands : Madeira Archipelago as a Case Study

Species distributional estimates are an essential tool to improve and implement effective conservation and management measures. Nevertheless, obtaining accurate distributional estimates remains a challenge in many cases, especially when looking at the marine environment, mainly due to the species mobility and habitat dynamism. Ecosystems surrounding oceanic islands are highly dynamic and constitute a key actor on pelagic habitats, congregating biodiversity in their vicinity. The main objective of this study was to obtain accurate fine-scale spatio-temporal distributional estimates of cetaceans in oceanic islands, such as the Madeira archipelago, using a long-term opportunistically collected dataset. Ecological Niche Models (ENM) were built using cetacean occurrence data collected on-board commercial whale watching activities and environmental data from 2003 to 2018 for 10 species with a diverse range of habitat associations. Models were built using two different datasets of environmental variables with different temporal and spatial resolutions for comparison purposes. State-of-the-art techniques were used to iterate, build and evaluate the MAXENT models constructed. Models built using the long-term opportunistic dataset successfully described distribution patterns throughout the study area for the species considered. Final models were used to produce spatial grids of species average and standard deviation suitability monthly estimates. Results provide the first fine-scale (both in the temporal and spatial dimension) cetacean distributional estimates for the Madeira archipelago and reveal seasonal/annual distributional patterns, thus providing novel insights on species ecology and quantitative data to implement better dynamic management actions.This study was supported by: (i) INTERTAGUA, MAC2/1.1.a/385 funded by MAC INTERREG 2014-2020, (ii) Oceanic Observatory of Madeira throughout the project M142001-0145-FEDER-000001-OOM, and (iii) Fundacao para a Ciencia e Tecnologia (FCT), Portugal, through the strategic project UID/MAR/04292/2020 granted to MARE UI&I. AD and FA have grants funded by ARDITI-Madeira's Regional Agency for the Development of Research, Technology and Innovation, throughout the project M1420-09-5369-FSE000002. RF was partially supported by a FCT doctoral grant (SFRH/BD/147225/2019).info:eu-repo/semantics/publishedVersio

Behavioural Ecology Traits of Elusive Deep-Diver Whales Unravel a Complex Social Structure Influenced by Female Philopatry and Defence Polygyny

Knowledge of the role of individual associations has provided an insightful understanding of the structures of animal societies, especially in highly social mammals such as primates. Yet, this is unbalanced towards marine mammals, particularly to beaked whales, due to their elusive nature. In addition, information on the fundamental drivers of the social structure of these deep-diving animals is still scarce. Here, the hypothesis of female defence polygyny was tested in Blainville’s beaked whales (Mesoplodon densirostris) and discussed within the context of marine and terrestrial organisms displaying similar patterns, by (i) estimating residency times to obtain information on the movements into and out of the area, (ii) analysing social networks to assess individual association metrics, (iii) measuring the strength of the associations to assess the existence of preferred or avoided relationships among individuals, and (iv) modelling different social structures to address temporal patterns in social relationships. Using a 9-year photographic dataset derived from the pelagic habitat, individual associations were inferred based on likelihood techniques. This approach allowed to infer on the species’ social structure in relation to age class, sex, residency status, and spatio-temporal patterns, which can be a good practice to be applied for other taxa. Heterogeneity in capture probability and residency times was observed between age-sex classes, with adult females exhibiting long-term site fidelity. This suggests different habitat roles and spatial structuring within this social organisation. Strong and long dyadic associations occurred between adult females and immatures, contrarily to between males, and the best-fitting models of the temporal patterns suggested long-lasting and temporary associations. The present findings unravel a complex social structure stratified by age-sex class and influenced by female philopatry and defence polygyny, like an unimale group mating system, which varies from other beaked whales but is similar to some birds, pinnipeds, or non-human primates.FUNDING: The Oceanic Observatory of Madeira and the Portuguese Foundation for Science and Technology (FCT) throughout the strategic projects M1420-01-0142-FEDER-000001 and UIDB/04292/2020, respectively. AB was supported by a MARE grant throughout the project UIDB/04292/2020, AD by ARDITI throughout the project M1420-09-5369-FSE-000002, RF by the FCT grant SFRH/BD/147225/2019, AS by the FCT grant SFRH/BD/141609/2018, MF by the MAC2/1.1a/385 in the framework of INTERTAGUA (MAC INTERREG 2014-2020), and FA by the FCT project UIDP/04292/2020 granted to MARE.info:eu-repo/semantics/publishedVersio

Ecophysiological traits of highly mobile large marine predators inferred from nucleic acid derived indices

Nucleic acid-derived indices such as RNA/DNA ratios have been successfully applied as ecophysiological indicators to assess growth, nutritional condition and health status in marine organisms given that they provide a measure of tissue protein reserves, which is known to vary depending on changes in the environment. Yet, the use of these biochemical indices on highly mobile large predators is scarce. In this study, we tested the applicability of using nucleic acids to provide insights on the ecophysiological traits of two marine mammal species (common bottlenose dolphins and short-finned pilot whales) and explored potential related factors (species, sex, season, and residency pattern), using skin tissue (obtained from biopsy darts) of apparently healthy and adult free-ranging animals. Significantly higher RNA/DNA ratios were obtained for bottlenose dolphins (p < 0.001), and for visitor pilot whales when compared with resident pilot whales (p = 0.001). No significant changes were found between the sexes. Based on the percentile approach, the samples contain individuals in a general good condition (as the 10th percentile is not closer to the mean than the 75th percentile), suggesting that the studied region of Macaronesia may be considered an adequate habitat. The combination of this effective tool with genetic sexing and photographic-identification provided an overall picture of ecosystem health, and although with some limitations and still being a first approach, it has the applicability to be used in other top predators and ecosystems.Portuguese Foundation for Science and Technology: UID/MAR/04292/2019/ UID/Multi/04326/2019/ UIDB/04423/2020info:eu-repo/semantics/publishedVersio

Solving a capacitated waste collection problem using an open-source tool

Increasing complexity in municipal solid waste streams worldwide is pressing Solid Waste Management Systems (SWMS), which need solutions to manage the waste properly. Waste collection and transport is the first task, traditionally carried out by countries/municipalities responsible for waste management. In this approach, drivers are responsible for decision-making regarding collection routes, leading to inefficient resource expenses. In this sense, strategies to optimize waste collection routes are receiving increasing interest from authorities, companies and the scientific community. Works in this strand usually focus on waste collection route optimization in big cities, but small towns could also benefit from technological development to improve their SWMS. Waste collection is related to combinatorial optimization that can be modeled as the capacitated vehicle routing problem. In this paper, a Capacitated Waste Collection Problem will be considered to evaluate the performance of metaheuristic approaches in waste collection optimization in the city of Bragança, Portugal. The algorithms used are available on Google OR-tools, an open-source tool with modules for solving routing problems. The Guided Local Search obtained the best results in optimizing waste collection planning. Furthermore, a comparison with real waste collection data showed that the results obtained with the application of OR-Tools are promising to save resources in waste collection.This work has been supported by FCT - Fundação para a Ciência e Tecnologia within the R &D Units Project Scope: UIDB/05757/2020, UIDB/00690/2020, UIDB/50020/2020, and UIDB/00319/2020. Adriano Silva was supported by FCT-MIT Portugal PhD grant SFRH/BD/151346/2021, and Filipe Alves was supported by FCT PhD grant SFRH/BD/143745/2019

Corrosion and tribocorrosion behaviour of Ti6Al4V produced by selective laser melting and hot pressing in comparison with the commercial alloy

The corrosion and tribocorrosion behaviour of SLM-produced Ti6Al4V alloy was studied in comparison with its HP and commercial counterparts in 9 g/L NaClsolution at body temperature. Results showed that SLM processing route influenced the electrochemical response of the SLM-produced alloy by leading to a relatively lower quality for the passive film due to decreased beta phase and the formation of alpha' phase. However, after tribocorrosion, neither the total volume loss nor the volume loss under the influence of mechanical wear and wear accelerated corrosion showed any statistically significant difference between the processing routes.This study was supported by FCT with the reference project UID/EEA/04436/2013, by FEDER funds through the COMPETE 2020 - Program Operacional Competitividade e Internacionalizacao (POCI) with the reference project POCI-01-0145-FEDER-006941, together with projects NORTE-01-0145-FEDER-000018-HAMaBICo and PTDC/EMS-TEC/5422/2014. The authors would also like to acknowledge Prof. Grata Minas for the provision of the profilometry

End-user assessment of an innovative clothing-based sensor developed for pressure injury prevention: a mixed-method study

This study aimed to evaluate a clothing prototype that incorporates sensors for the evaluation of pressure, temperature, and humidity for the prevention of pressure injuries, namely regarding physical and comfort requirements. A mixed-method approach was used with concurrent quantitative and qualitative data triangulation. A structured questionnaire was applied before a focus group of experts to evaluate the sensor prototypes. Data were analyzed using descriptive and inferential statistics and the discourse of the collective subject, followed by method integration and meta-inferences. Nine nurses, experts in this topic, aged 32.66 ± 6.28 years and with a time of profession of 10.88 ± 6.19 years, participated in the study. Prototype A presented low evaluation in stiffness (1.56 ± 1.01) and roughness (2.11 ± 1.17). Prototype B showed smaller values in dimension (2.77 ± 0.83) and stiffness (3.00 ± 1.22). Embroidery was assessed as inadequate in terms of stiffness (1.88 ± 1.05) and roughness (2.44 ± 1.01). The results from the questionnaires and focus groups’ show low adequacy as to stiffness, roughness, and comfort. The participants highlighted the need for improvements regarding stiffness and comfort, suggesting new proposals for the development of sensors for clothing. The main conclusions are that Prototype A presented the lowest average scores relative to rigidity (1.56 ± 1.01), considered inadequate. This dimension of Prototype B was evaluated as slightly adequate (2.77 ± 0.83). The rigidity (1.88 ± 1.05) of Prototype A + B + embroidery was evaluated as inadequate. The prototype revealed clothing sensors with low adequacy regarding the physical requirements, such as stiffness or roughness. Improvements are needed regarding the stiffness and roughness for the safety and comfort characteristics of the device evaluated.The 4NoPressure project was co-financed by the Operational Program for Competitiveness and Internationalization (COMPETE 2020) under the PORTUGAL 2020 Partnership Agreement, with support from the European Regional Development Fund (ERDF), reference number POCI-01-0247- FEDER-039869

Room temperature paramagnetism of ZnO:Mn films grown by RF-sputtering

ZnO:Mn transparent thin films (thickness b1 μm) with the Mn contents ranging from 1.8 to 3.25 at.% were grown by RF magnetron co-sputtering. The films are nanocrystalline, with wurtzite-structure grains of a typical size of 20 nm and with a preferential orientation of the c-axis perpendicular to the surface. According to the Raman spectroscopy data, Mn mostly substitutes Zn in the lattice sites. In spite of these factors, the nanostructure and the Mn(Zn) substitution, that are considered favorable for ferromagnetism in this material, both magnetic resonance and Faraday effect measurements show paramagnetic behavior of the ZnO:Mn films and the absence of ferromagnetic order at room temperature.FCT throughproject PTDC/FIS/72843/200