Browsing by Issue Date, starting with "2019-07"
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- μCT trait analysis reveals morphometric differences between domesticated temperate small grain cereals and their wild relativesPublication . Hughes, Nathan; R. Oliveira, Hugo; Fradgley, Nick; Corke, Fiona M K; Cockram, James; Doonan, John H; Nibau, CandidaWheat and barley are two of the founder crops domesticated in the Fertile Crescent, and currently represent crops of major economic importance in temperate regions. Due to impacts on yield, quality and end-use, grain morphometric traits remain an important goal for modern breeding programmes and are believed to have been selected for by human populations. To directly and accurately assess the three-dimensional (3D) characteristics of grains, we combine X-ray microcomputed tomography (μCT) imaging techniques with bespoke image analysis tools and mathematical modelling to investigate how grain size and shape vary across wild and domesticated wheat and barley. We find that grain depth and, to a lesser extent, width are major drivers of shape change and that these traits are still relatively plastic in modern bread wheat varieties. Significant changes in grain depth are also observed to be associated with differences in ploidy. Finally, we present a model that can accurately predict the wild or domesticated status of a grain from a given taxa based on the relationship between three morphometric parameters (length, width and depth) and suggest its general applicability to both archaeological identification studies and breeding programmes.
- Metal contamination in Ria Formosa saltmarsh sediments and halophyte vegetationPublication . Silva, Manuela; Duarte, Duarte; Chicharo, LuisSaltmarsh vegetation may retain certain substances from anthropogenic activities in surrounding areas, providing a control of contaminants such as heavy metals, coming from industry, agriculture and urbanization. In the last decades there are been na increase in urbanization and industrialization of the area surrounding Marim – Ria Formosa, where this study was performed.
- Role of the Ria Formosa inlets on the physical, chemical and biological exchanges with the adjoining oceanPublication . Cravo, Alexandra; Jacob, J.A coastal lagoon is a “shallow coastal water body separated from the ocean by a barrier, connected at least intermittently to the ocean by one or more restricted inlets” (Kjerfve, 1994). Coastal lagoons are typically found along low-lying coastlines, affected by a tidal range < 4 m and generally < 5 m deep (Bird, 1994; Kjerfve,1994). Coastal lagoons are important ecosystems because these support a wide range of natural services, highly valuable for society. These complex systems provide food, storm protection, tourism, among others. So, they contribute to the overall productivity of coastal waters by sustaining a variety of habitats, including salt marshes, seagrasses, and/or mangroves particularly important for many fish and shellfish species. Water quantity and quality in a lagoon is influenced by the rate at which the lagoon loses or gains water from exchange with the ocean, surface runoff, evaporation, precipitation and groundwater (Allen et al., 1981).
- POPC/Cholesterol lipid bilayers: A matter of polarityPublication . Cristo, Joana; M. Martins, JorgeWater is an important component of lipid membranes and contributes for the stabilization of the bilayer structure. It determines the polarity gradient in lipid bilayers, since the amount of water at the lipid/water interface is higher than in the acyl chains region.
- Gas-phase conversion of glycerol to allyl alcohol over vanadium-supported zeolite betaPublication . Almeida, Ruben; Filipa Ribeiro, M.; Fernandes, Auguste; Lourenço, João PauloVanadium oxide supported beta zeolite (Si/Al = 25, 4% V) was used as catalyst for the one-pass gas-phase conversion of glycerol to allyl alcohol without any external reductant. The catalytic data strongly suggest a consecutive reactions path involving the dehydration to acrolein over the zeolite acid sites followed by a selective reduction through a hydrogen-transfer reaction. Acidity is expected to play a major role in what concerns the selectivity, as demonstrated by the catalytic results obtained by the impregnation of vanadium on a previously Cs-exchanged sample that achieved ca. 30% selectivity to allyl alcohol at ca. 20% glycerol conversion.
- A cost-effective retrofitting technique for urm buildings based on steel encirclements in openings: a case studyPublication . Segovia-Verjel, María-Luisa; Justo-Moscardó, E.; Morales-Esteban, Antonio; Requena-Garcia-Cruz, María-Victoria; Romero-Sánchez, Emilio; de-Miguel-Rodríguez, Jaime; Estêvão, João M. C.A project named PERSISTAH is being developed to study the seismic vulnerability of primary schools in Huelva (Spain) and the Algarve (Portugal). This area has a moderate seismicity but this is affected by a nearby area where earthquakes of large magnitude (Mw≥6) and longreturn periods happen. The seismic vulnerability of URM (UnReinforced Masonry) buildings has been observed and analysed in the last decades. The seismic retrofitting of these buildings is required in order to improve their seismic behaviour. Many retrofitting techniques have been developed for that purpose, most of them very complicated and expensive. Therefore, these are not appropriate to retrofit a large number of buildings. This is especially relevant in areas of moderate seismicity where the cost-efficiency ratio must be carefully considered. The aim of this paper has been to develop a simple, effective and affordable technique to retrofit these buildings. These buildings are characterised by numerous openings which causes a great weakness in the URM walls. Then, a technique that consists in installing a steel encirclement or a grille in the openings of the walls has been proposed. This is a specific retrofitting technique for URM walls since this technique substantially improves the seismic capacity of these structures. To test the technique a case study is proposed. The building under study is a primary school located in Huelva and built in 1961. Results have shown that the capacity of the building is notably increased. Also, the performance point and the damage level of the structure are decreased.
- Workplace empowerment and job satisfaction in portuguese nurses an explicative modelPublication . Almeida, H.; Orgambidez, AlejandroGreater effectiveness of health care does occur with a more effective management of interpersonal processes. A working management environment, which ensures sufficient access to information, support, resources, and opportunities (structural empowerment), probably can promote a personal perception of capacity and effectiveness (global empowerment) in caregivers to achieve organizational objectives and job satisfaction. This study evaluated the relationship between empowerment and job satisfaction, supported by Kanter's theory of structural empowerment. This study used a convenience sample of 151 nurses from public Portuguese hospitals. The adjustment of the model and the effect of mediation were carried out with a structural equation model (path analysis) through the statistical software STATA. The results show the mediator effect of global empowerment on the relationship between structural empowerment and job satisfaction and the direct and indirect effects of "access to opportunities" in job satisfaction. Managers of these health units should consider that the more the work environment is characterized by having the resources, opportunities, and support indispensable to the good execution of the work by the nurses, the greater the global empowerment and job satisfaction. The results obtained can be an important contribution that can be adopted as a strategy in any health institution without any harm.
- Preface: Ria Formosa. Challenges of a coastal lagoon in a changing environmentPublication . Marques, MiguelThis book entitled "RIA FORMOSA. Challenges of a coastal lagoon in a changing environment" is na astonishing exercise of disclosing the main challenges of Ria Formosa, a vital lagoon for the Algarve Region and for Portugal as a whole. Coastal interface areas between sea and land are very important, rich, sensitive and extremely dynamic areas. There are multiple and complex changes that, either by nature or by human action, occur in coastal zones, from erosion to silting phenomena, from changes in currents to floods ... This lagoon system, protected by barrier-islands with dunes, is the support of relevant economic activities. Apparently, these barrier-islands were born in the sea and are in permanent movement, towards the continent. The movement is visible, within a decade, there are areas of sand that are decreasing dangerously and others to gain more sand.
- New unique optical and electric properties of intermediate filaments in Muller cellsPublication . Khmelinskii, Igor; Makarov, VladimirPresently we report new unique optical and electric properties of Muller cell (MC) intermediate filaments (IFs). We inform that these IFs extracted from porcine retina are excellent conductors of light and electric current. Such IF properties may endow vertebrate eyes with high-contrast vision. The properties of the IFs allow a simple quantum-mechanical description that justifies the quantum mechanism (QM) for the light energy transfer between the inner and the outer limiting membranes. These properties also provide direct and unequivocal proof that QM works even in isolated IFs, while the classic theory admits no capacity for light transmission by objects that are so thin. Note that the length and diameter of the IFs were 117 +/- 1.3 mu m and 10.1 +/- 0.07 nm, respectively. The QM avoids the light scattering effects, which could significantly reduce the visual contrast, by conducting light energy in the form of excitons (excited states). This scientific breakthrough may provide new insights for medical ophthalmology.
- Survival rates and physiological recovery responses in the lesser-spotted catshark (Scyliorhinus canicula) after bottom-trawlingPublication . Barragan-Mendez, C.; Ruiz-Jarabo, I.; Fuentes, Juan; Mancera, J. M.; Sobrino, I.In 2019, Europe will adopt a no-discards policy in fisheries. This entails the landing of captured species unless strong evidence is provided supporting their survival and recovery after fishing. Thus, research on this topic is gaining momentum. Bottom-trawling, as a non-selective fishing method, is characterized by a high proportion of discards including vulnerable key species, such as demersal sharks. Their survival may also depend on capture depth. By paralleling onboard and laboratory experiments with the small-spotted catshark, Scyliorhinus canicula, we offer a robust experimental design to assess the survival of discarded sharks. Catsharks were captured by bottom-trawling at two depths (shallow similar to 89 m and deep similar to 479 m). Blood samples were collected following trawl capture and analyzed for stress biomarkers (lactate, osmolality, phosphate, urea). During recovery in onboard tanks, behavior was video-recorded and fish were re-sampled after 24 h. A second experiment was conducted in laboratory facilities to simulate air-exposure after trawling and to analyze the physiological recovery. Our results showed that 95.7% of the animals survived 24 h after trawling. We confirmed that trawling elicited acute stress responses in catshark but that they managed to recover. This was demonstrated by lactate concentrations that were 2.6 mM upon capture, but recovered to assumed baselines after 24 h (0.2 mM). Non-invasive video monitoring revealed behavioral differences with depth, whereby those captured at 89 m depth required longer to recover than those captured at 479 m depth. Implementation of standardized survival studies by fishery managers can benefit from holistic physiological approaches, such as the one proposed here.