Bathymetric surveys from SAR satellite images using wavelets

When waves propagate in coastal areas they sufer changes in the wavelength and wave direction resulting from the interaction with the sea bottom. In SAR images, the waves can be identify through variations in the gray tones of the image, making it possible to infer the bathymetry from the variations in the wavelength. Commonly, the fast Fourier transform (FFT) is used to estimate the wavelength in domains close to the coast, recognizing, however, that this method has some limitations, mainly for small depths. To overcome the limitations of FFT, this work uses wavelet spectral analysis to estimate bathymetric data. The new image processing methodology shows positive and promising results for mapping shallow marine environments.Peer Reviewe

Nearshore Bathymetry Retrieval from Wave-Based Inversion for Video Imagery

A wavelet-based method for bathymetry retrieval using a sequence of static images of the surface wave field, as obtained from video imagery, is proposed. Synthetic images of the water surface are generated from a numerical Boussinesq type model simulating the propagation of irregular waves. The spectral analysis is used to retrieve both wave periods and wavelengths by evaluating the spectral peaks in the time and spatial domains, respectively. The water depths are estimated using the linear dispersion relation and the results are validated with the model’s bathymetry. To verify the proposed methodology, 2D and 3D simulations considering effects of wave shoaling and refraction were performed for different sea conditions over different seafloors. The method’s ability to reproduce the original bathymetry is shown to be robust in intermediate and shallow waters, being also validated with a real case with images obtained with a shore-based video station. The main improvements of the new method compared to the consideration of a single image, as often used in Satellite Derived Bathymetry, is that the use of successive images enables the consideration of different wave periods, improving depth estimations and not requiring the use of subdomains or filters. This image processing methodology shows very positive results to provide bathymetry maps for shallow marine environments and can be useful to monitor the nearshore with high time- and space-resolution at low cost.This research was funded by Direção Geral da Política do Mar, through projectNAVSAFETY of the Fundo Azul program. Thanks are due to FCT/MCTES (PT) for the financial support to CESAM (UIDP/50017/2020 + UIDB/50017/2020 + LA/P/0094/2020), through national funds and to the project Space for Shore funded through EOEP 5 Coastal Erosion Program (ESA/AO/1-9219/18/I-LG).info:eu-repo/semantics/publishedVersio

Elza Nadai: a formação da papisa do ensino de História

O trabalhodebruça-sesobre a trajetória intelectual de Elza Nadai, no intuito de visualizar os locais institucionais e as proposições teóricas que edificaram a área de pesquisa de ensino de História. O recorte temporal privilegiado situa-se entre as décadas de 1960 a 1980: a graduação naUniversidade de São Paulo, passagem pelo Serviço de Ensino Vocacional, e a entrada na pós-graduação e o início da docência no ensino superior. Elaborava-se uma concepção de ensino de História que partia da problematização da realidade juntamente aos princípios da História Temática, bastante vinculada à defesa dos ideais democráticos e de justiça social, estimulada também pelo movimento estudantil. As fontes mais destacadas foram os trabalhos de pós-graduação de Elza, documentos encontrados nos arquivos do Centro de Memória da Educação da FE/USP e entrevistas orais. As reflexões também buscam elementos da sensibilidade, fatores impulsionadores dos grandes projetos acadêmicos, a afetividade e as relações de poder

3D biocomposites comprising marine collagen and silica-based materials inspired on the composition of marine sponge skeletons envisaging bone tissue regeneration

Ocean resources are a priceless repository of unique species and bioactive compounds with denouement properties that can be used in the fabrication of advanced biomaterials as new templates for supporting the cell culture envisaging tissue engineering approaches. The collagen of marine origin can be sustainably isolated from the underrated fish processing industry by-products, while silica and related materials can be found in the spicules of marine sponges and diatoms frustules. Aiming to address the potential of biomaterials composed from marine collagen and silica-based materials in the context of bone regeneration, four different 3D porous structure formulations (COL, COL:BG, COL:D.E, and COL:BS) were fabricated by freeze-drying. The skins of Atlantic cod (Gadus morhua) were used as raw materials for the collagen (COL) isolation, which was successfully characterized by SDS-PAGE, FTIR, CD, and amino acid analyses, and identified as a type I collagen, produced with a 1.5% yield and a preserved characteristic triple helix conformation. Bioactive glass 45S5 bioglass® (BG), diatomaceous earth (D.E.) powder, and biosilica (BS) isolated from the Axinella infundibuliformis sponge were chosen as silica-based materials, which were obtained as microparticles and characterized by distinct morphological features. The biomaterials revealed microporous structures, showing a porosity higher than 85%, a mean pore size range of 138â 315 µm depending on their composition, with 70% interconnectivity which can be favorable for cell migration and ensure the needed nutrient supply. In vitro, biological assays were conducted by culturing L929 fibroblast-like cells, which confirmed not only the non-toxic nature of the developed biomaterials but also their capability to support cell adhesion and proliferation, particularly the COL:BS biomaterials, as observed by calcein-AM staining upon seven days of culture. Moreover, phalloidin and DAPI staining revealed well-spread cells, populating the entire construct. This study established marine collagen/silica biocomposites as potential scaffolds for tissue engineering, setting the basis for future studies, particularly envisaging the regeneration of non-load-bearing bone tissues.This research was funded by European Union’s Horizon 2020 Framework Programme for Research and Innovation under the projects SponGES (H2020-BG-01-2015-679849)

Is leg kicking workout position affecting kinematic and hydrodynamic variables in front-craw?

Swimming training includes leg kicking workouts, whereas swimmerschoose betweenhead out (RO) or headin (HI) position holding afllitter kick board. Ourobjective was to characterize andanalyse differences between the t\vo legkicking positions in Swimming Vdocity (Y, 1n m/s), lntra-cyclic variation of the horizontal velocity (dv, dimensionless), Active Drag (D, in N), Hydrodynamic Coefficient (CD •. dimensionless), Mechanical Power (P, in W) andfrontal surfacearea (FSA, ia m2). Thirteen swimmers (15.3 ± 2,9 years~old) participated in thisstudy. Frontal surface area was calculated according to the proposal of Morais et aI. (201l)byphotogrammetry. Aftefa standard warmup, swimmers performed 4x25mbouts at maximum velocity as follows: i) 2XcrawI HO Ieg-kick; ii) 2XcrawI HI Ieg-kick. ln the first bout ofeach the V and the dv were measured usingaspeedmeter cable that Was attached to lhe swimmer's hip (Barbosaet aI., 2013). In the secondbout CD was obtained through the velocity perturbation method (Kolmogorov and Duplishcheva, 1992).info:eu-repo/semantics/publishedVersio

Compressed earth blocks stabilized with glass waste and fly ash activated with a recycled alkaline cleaning solution

Sustainable alternatives are increasingly demanded as a sound response, from the construction industry, to the worldwide growing concerns with the environment. Such effort is justifiable by the degree of the contribution of this human activity to the problem, and it has thus propelled the development of a major trend in terms of funded research. The study reported in this paper focused on the physical-mechanical properties of compacted earth blocks formed by a common Portuguese silty clay (as the mineral skeleton), stabilized with a sustainable alkali activated cement exclusively produced from wastes and residues, including coal fly ash and glass waste, in a 50/50 wt ratio combination, and activated with an alkaline solution from the aluminium industry, using activator/precursor weight ratios of 0.50, 0.57 and 0.75. After optimising the alkaline activated cement (AAC), the AAC/Soil blocks were fabricated, using the response surface method to define their composition based on curing periods of 28 and 180 days at controlled ambient temperature. Uniaxial compressive strength (UCS) and several durability tests were performed, and the material was characterised using FTIR and SEM. The results evidenced the effectiveness of the alkaline cementing agent in forming a binding matrix for the soil particles. An average compressive strength of 17.23 MPa, in unsaturated conditions, was obtained for the blocks. The newly formed soil-binder structure was very capable to withstand wetting and drying cycles, ice-thaw cycles and erosion. The microstructure of the material was further analysed, using scanning electron microscopy and energy dispersive spectroscopy. The results demonstrated the real possibility of using this type of cement as a viable alternative to traditional soil stabilisation binders used in earth construction.This work was funded by the R&D Project JUSTREST-Development of Alkali Binders for Geotechnical Applications Made Exclusively from Industrial Waste, with reference PTDC/ECM-GEO/0637/2014, financed by the Foundation for Science and Technology - FCT/MCTES (PIDDAC).The research was supported by the GEO-DESIGN project, no17501, co-financed by the European Regional Development Fund (ERDF) through NORTE 2020 (North Regional Operational Program, 2014/2020)

Macro and microstructural characteristics of north Atlantic deep-sea sponges as bioinspired models for tissue engineering scaffolding

Sponges occur ubiquitously in the marine realm and in some deep-sea areas they dominate the benthic communities forming complex biogenic habitats â sponge grounds, aggregations, gardens and reefs. However, deep-sea sponges and spongegrounds are still poorly investigated with regards to biotechnological potential in support of a Blue growth strategy. Under the scope of this study, five dominant North Atlantic deep-sea sponges, were characterized to elucidate promising applications in human health, namely for bone tissue engineering approaches. Geodia barretti (Gb), Geodia atlantica (Ga), Stelletta normani (Sn), Phakellia ventilabrum (Pv), and Axinella infundibuliformis (Ai), were morphologically characterized to assess macro and microstructural features, as well as chemical composition of the skeletons, using optical and scanning electron microscopy, energy dispersive x-ray spectroscopy and microcomputed tomography analyses. Moreover, compress tests were conducted to determine the mechanical properties of the skeletons. Results showed that all studied sponges have porous skeletons with porosity higher than 68%, pore size superior than 149 mm and higher interconnectivity (>96%), thus providing interesting models for the development of scaffolds for tissue engineering. Besides that, EDS analyses revealed that the chemical composition of sponges, pointed that demosponge skeletons are mainly constituted by carbon, silicon, sulfur, and oxygen combined mutually with organic and inorganic elements embedded its internal architecture that can be important features for promoting bone matrix quality and bone mineralization. Finally, the morphological, mechanical, and chemical characteristics here investigated unraveled the potential of deep-sea sponges as a source of biomaterials and biomimetic models envisaging tissue engineering applications for bone regeneration.The authors would like to acknowledge the funding from the European Union Framework Program for Research and Innovation Horizon 2020 through project SponGES (H2020- BG-01-2015-679849) and from the Northern Portugal Regional Operational Program (NORTE2020), under the Portugal 2020 Partnership Agreement, through the Structured projects for R&D&I NORTE-01-0145-FEDER-000021 and NORTE-01-0145- FEDER-000023. JRX research was further supported by national funds through FCT Foundation for Science and Technology within the scope of UIDB/04423/2020 and UIDP/04423/2020, and CEECIND/00577/2018

REVASCULARIZAÇÃO CONVENCIONAL ULTRA-DISTAL NA ISQUEMIA CRÍTICA

Introdução: A cirurgia convencional de revascularização ultra-distal continua a ser pouco utilizada pela maioria dos cirurgiões vasculares. No entanto, os escassos estudos publicados mostram resultados muito favoráveis em termos de sobrevida e salvação de membro. Objetivos: Avaliar os resultados da cirurgia convencional de revascularização ultra-distal em doentes com isquemia crítica grau IV (estadios 5 e 6 da classificação de Rutherford); analisar os detalhes técnicos e de decisão cirúrgica que influenciam os resultados obtidos. Material e métodos: Estudo retrospetivo, envolvendo todos os doentes admitidos nesta instituição com isquemia crítica nos estadios 5 e 6 da classificação de Rutherford, submetidos a cirurgia convencional de revascularização ultra-distal. Foi considerado critério de inclusão a cirurgia de bypass às artérias plantares comum, interna ou externa e à artéria pediosa. Foi avaliada a mortalidade, taxa de preservação de membro, sobrevida livre de amputação major e permeabilidade da revascularização, por intermédio de curvas de Kaplan-Meier. Resultados: Entre Abril de 2012 e Março de 2016, 41 doentes (34 homens e 7 mulheres) com uma média de idades de 69.1 anos, foram submetidos a 50 procedimentos de revascularização ultra-distal, 35 dos quais à artéria pediosa, 10 a artérias plantares e 5 a procedimentos de resgate de failing graft. Em 84% das revascularizações (n=42) utilizou-se substituto venoso autólogo, sendo os restantes bypass compostos de PTFE e veia (n=8). O follow-up médio foi de 20.8 meses (2-47 meses). Não registámos qualquer mortalidade aos 30 dias e durante o follow-up a mortalidade global foi 7.3% (n=3). Ocorreram 9 oclusões das revascularizações (2 precoces e 7 tardias) e 5 amputações major. A permeabilidade primária foi de 78% e a permeabilidade primária assistida de 82%. A taxa de preservação de membro foi de 88.9% e, no final do follow-up, a sobrevida livre de amputação foi de 66%. Conclusões: Os resultados demonstram que, em centros especializados e com elevado volume, esta técnica é muito eficaz na salvação de membros em isquemia crítica nos estadios 5 e 6 da classificação de Rutherford. Estes procedimentos devem ser tomados em consideração na ausência de outros vasos pontáveis ou como resgate, em membros já submetidos a procedimentos de revascularização prévios

Epidemiology of periodontal disease among the elderly

The present study aims to reflect on the oral health status of the elderly, addressing periodontal disease, as well as the importance of oral health, general health and quality of life. The methodology adopted consisted of a bibliographic research of scientific articles indexed in PUBMED® and Google Scholar® with the following combined keywords: “Periodontal Disease”, “Gerodontology”, “Oral Health”, “Elderly” and “Epidemiology”, either in Portuguese or in English. The exclusion criteria for the selection of the scientific articles used consisted in limiting the research to the Portuguese and English languages, limiting the publication date to the last 10 years, and only scientific articles referring to the epidemiology of periodontal disease among the elderly. Therefore, from a total of 33 scientific articles, only 17 scientific articles were selected for the present research. The most recent studies do show that periodontal disease is clearly a public health issue, increasing among all ages. However, this oral pathology should be carefully analyzed among the elderly considering the higher risk of association with the development of other systemic diseases and also the physiological, mental and social changes that characterize this specific age group.info:eu-repo/semantics/publishedVersio

Effect of vineyard characteristics on the functional diversity of insectivorous birds as indicator of potential biocontrol services

Insectivorous birds have a large potential to provide biocontrol services in vineyards, thus contributing to the sustainability of this agroecosystem. Bird communities are influenced by vineyard management practices and surrounding landscape, which may influence their role as ecosystem service providers. Functional diversity indices are indicators of bird community composition, and thus may reflect potential biocontrol services. We surveyed 31 vineyard plots in southern Portugal to assess vineyard characteristics (management intensity and landscape context) that may influence functional insectivorous birds in vineyards, using seven functional diversity indices as potential biocontrol indicators. We used eight characteristics of vineyard plots to define three vineyard types for our case-study: TREE – smaller vineyard plots surround by a more diverse landscape, with larger proportion of tree-habitats; AGRI – vineyard plots with medium size and greater cover by herbaceous vegetation, mostly surrounded by agricultural habitats (pastureland, crops); and VINE – vineyard plots of larger size and higher inter-row herbaceous vegetation, often surrounded by other vineyard plots. Five potential biocontrol indicators seemed to vary according to vineyard type. The richness of functional insectivorous birds, functional dispersion, functional richness, and Rao’s functional diversity were all higher in vineyard TREE type compared to both AGRI and VINE types. The functional divergence was higher in vineyard TREE type than in VINE type, but similar to AGRI type. Accordingly, TREE type vineyards hold bird communities with more diverse and widespread ecological functions. This implies that smaller vineyard plots, in more heterogeneous landscapes, with neighbouring woodlands seem to have a higher potential of biocontrol services provided by insectivorous birds as suggested by using functional diversity indices as indicators