6,368 research outputs found
Estimating trade balance for a small region: Beira–Estrela, Portugal
This paper estimates the trade balance for a small region located in inland Portugal – Beira Estrela – geographically defined as the merge of 3 official NUT III regions – Beira Interior Norte, Serra da Estrela and Cova da Beira. This estimate disaggregates by 31 commodities and includes four essential parts: first, the international trade of goods and services; second, the interregional trade of the same commodities; third, the net balance between in-region consumption by foreigner non-residents and the international consumption by residents and finally the equivalent net balance for Portuguese tourists visiting Beira-Estrela and the consumption of out Beira-Estrela Portuguese residents. Interregional trade (not available in official statistics) is the residual between supply and demand of the different groups of commodities corresponding to the columns and rows of a regional Make and Use table we derive for Beira-Estrela. This regional matrix is the outcome of the application of a simplified non-survey method to the Portuguese (National Accounts provided) Make and Use table decomposition. Moreover we set a survey on lodging and restaurant users that allowed the detachment of the interregional tourist consumption flows from the remaining interregional trade. The aim of this estimate is to assess the relative importance of tourism in the Beira-Estrela regional trade balance. Furthermore, we argue in the paper that, unlike countries, regions do not benefit from trade surpluses and these surpluses are just the counterpart of the income drainage or capital outflows, which weaken the economic region basis.
An overview of the hooking mortality of elasmobranchs caught in a swordfish pelagic longline fishery in the Atlantic Ocean
Hooking (or “at-haulback”) fishing mortality was analysed in elasmobranchs captured by Portuguese longliners targeting swordfish in the Atlantic Ocean. Information was collected by on-board fishery observers who monitored 834 longline fishing sets between August 2008 and December 2011, and recorded information on 36,067 elasmobranch specimens from 21 different taxa. The hooking mortality proportions were species-specific, with some species having relatively high percentages of live specimens at time of haulback (e.g., blue shark, crocodile shark, pelagic stingray, manta, devil and eagle rays), while others had higher percentages of dead specimens (e.g., smooth hammerhead, silky shark, bigeye thresher). For the most captured species, logistic GLMs were carried out to compare the mortality rates between sexes, specimen sizes and the regions of operation of the fleet. The sex-specific proportions of hooking mortality were significantly different for blue and crocodile sharks, with the males of both species having higher proportions of hooking mortality than the females. Specimen size was significant for predicting the hooking mortality for blue and shortfin mako sharks: in both cases, the larger specimens had lower odds of dying due to the fishing process. There were differences in the hooking mortality depending on the region of operation of the fleet, but those differences were also species-specific. For blue and crocodile sharks, the hooking mortality was higher in the Equatorial and southern Atlantic areas (when compared to the NE Atlantic region), while the opposite was observed for the shortfin mako, with lower mortality rates in the NE tropical area compared with the other regions. The results presented in this paper can be integrated into future ecological risk assessment analysis for pelagic elasmobranchs. Furthermore, the new information can be used to evaluate the impact of recent recommendations prohibiting the retention of some vulnerable elasmobranch species
Unveiling the Dynamics of the Universe
We explore the dynamics and evolution of the Universe at early and late
times, focusing on both dark energy and extended gravity models and their
astrophysical and cosmological consequences. Modified theories of gravity not
only provide an alternative explanation for the recent expansion history of the
universe, but they also offer a paradigm fundamentally distinct from the
simplest dark energy models of cosmic acceleration. In this review, we perform
a detailed theoretical and phenomenological analysis of different modified
gravity models and investigate their consistency. We also consider the
cosmological implications of well motivated physical models of the early
universe with a particular emphasis on inflation and topological defects.
Astrophysical and cosmological tests over a wide range of scales, from the
solar system to the observable horizon, severely restrict the allowed models of
the Universe. Here, we review several observational probes -- including
gravitational lensing, galaxy clusters, cosmic microwave background temperature
and polarization, supernova and baryon acoustic oscillations measurements --
and their relevance in constraining our cosmological description of the
Universe.Comment: 94 pages, 14 figures. Review paper accepted for publication in a
Special Issue of Symmetry. "Symmetry: Feature Papers 2016". V2: Matches
published version, now 79 pages (new format
Photo2Video: Semantic-Aware Deep Learning-Based Video Generation from Still Content
Applying machine learning (ML), and especially deep learning, to understand visual content is becoming common practice in many application areas. However, little attention has been given to its use within the multimedia creative domain. It is true that ML is already popular for content creation, but the progress achieved so far addresses essentially textual content or the identification and selection of specific types of content. A wealth of possibilities are yet to be explored by bringing the use of ML into the multimedia creative process, allowing the knowledge inferred by the former to influence automatically how new multimedia content is created. The work presented in this article provides contributions in three distinct ways towards this goal: firstly, it proposes a methodology to re-train popular neural network models in identifying new thematic concepts in static visual content and attaching meaningful annotations to the detected regions of interest; secondly, it presents varied visual digital effects and corresponding tools that can be automatically called upon to apply such effects in a previously analyzed photo; thirdly, it defines a complete automated creative workflow, from the acquisition of a photograph and corresponding contextual data, through the ML region-based annotation, to the automatic application of digital effects and generation of a semantically aware multimedia story driven by the previously derived situational and visual contextual data. Additionally, it presents a variant of this automated workflow by offering to the user the possibility of manipulating the automatic annotations in an assisted manner. The final aim is to transform a static digital photo into a short video clip, taking into account the information acquired. The final result strongly contrasts with current standard approaches of creating random movements, by implementing an intelligent content- and context-aware video.The work presented in this paper has been supported by the European Commission under
contract number H2020-ICT-20-2017-1-RIA-780612 and by National Funds through the Portuguese
funding agency, FCT—Fundação para a Ciência e a Tecnologia, within project LA/P/0063/2020.info:eu-repo/semantics/publishedVersio
Atividade física e desportiva em crianças com necessidades educativas especiais: inclusão, adaptações e bullying
Projeto de investigaçãoAs motivações para o desenvolvimento do presente estudo surgem do interesse
da temática da inclusão de crianças com necessidades especiais nas práticas de
educação física regular das escolas públicas e compreender até que ponto os
professores estão ligados ao fenómeno de inclusão e bullying. Identificaremos
como os alunos se envolvem no bullying e quais os a conceitos de ética e de
axiologia a aplicar como recurso às actividades desenvolvidas nas aulas de
Educação Física.Fundação para a Ciência e a Tecnologia (FCT) - unidade de investigação 31
Complex fluid flow in microchannels and heat pipes with enhanced surfaces for advanced heat conversion and recovery systems
This paper addresses a multiscale approach for heat recovery systems, used in two distinct applications. In both applications, a microscale approach is used (microchannel heat sinks and heat pipes) for macroscale applications (cooling of a photovoltaic—PV cell), and the thermal energy of exhaust gases of an internal combustion engine is used for thermoelectric generators with variable conductance heat pipes. Several experimental techniques are combined such as visualization, thermography with high spatial and temporal resolution, and the characterization of the flow hydrodynamics, such as the friction losses. The analysis performed evidences the relevance of looking at the physics of the observed phenomena to optimize the heat sink geometry. For instance, the results based on the dissipated heat flux and the convective heat transfer coefficients obtained in the tests of the microchannel-based heat sinks for cooling applications in PV cells show an improvement in the dissipated power at the expense of controlled pumping power, for the best performing geometries. Simple geometries based on these results were then used as inputs in a genetic algorithm to produce the optimized geometries. In both applications, the analysis performed evidences the potential of using two-phase flows. However, instabilities at the microscale must be accurately addressed to take advantage of liquid phase change. In this context, the use of enhanced interfaces may significantly contribute to the resolution of the instability issues as they are able to control bubble dynamics. Such an approach is also addressed here.Authors acknowledge to Fundação para a Ciência e a Tecnologia¸ FCT and PORTUGAL
2020 Partnership Agreement, through the European Regional Development Fund, for partially financing this project through projects PTDC/EME-TED/7801/2020, JICAM/0003/2017, UIDB/00481/2020,
UIDP/00481/2020, and CENTRO-01-0145-FEDER-022083 (Centro2020) and for funding the scholarship of Pedro Pontes, ref. SFRH/BD/149286/2019
Potassium Intake and Blood Pressure: A Dose-Response Meta-Analysis of Randomized Controlled Trials
BACKGROUND: Epidemiologic studies, including trials, suggest an association between potassium intake and blood pressure (BP). However, the strength and shape of this relationship is uncertain. METHODS AND RESULTS: We performed a meta-analysis to explore the dose-response relationship between potassium supplementation and BP in randomized-controlled trials with a duration >= 4 weeks using the recently developed 1-stage cubic spline regression model. This model allows use of trials with at least 2 exposure categories. We identified 32 eligible trials. Most were conducted in adults with hypertension using a crossover design and potassium supplementation doses that ranged from 30 to 140 mmol/d. We observed a U-shaped relationship between 24-hour active and control arm differences in potassium excretion and BP levels, with weakening of the BP reduction effect above differences of 30 mmol/d and a BP increase above differences similar to 80 mmol/d. Achieved potassium excretion analysis also identified a U-shaped relationship. The BP-lowering effects of potassium supplementation were stronger in participants with hypertension and at higher levels of sodium intake. The BP increase with high potassium excretion was noted in participants with antihypertensive drug-treated hypertension but not in their untreated counterparts. CONCLUSIONS: We identified a nonlinear relationship between potassium intake and both systolic and diastolic BP, although estimates for BP effects of high potassium intakes should be interpreted with caution because of limited availability of trials. Our findings indicate an adequate intake of potassium is desirable to achieve a lower BP level but suggest excessive potassium supplementation should be avoided, particularly in specific subgroups
Space perception in virtual environments: On how biometric sensing in virtual environments may give architects users's feedback
This paper focuses on the objective study of emotions, namely, fear induced by architectural spaces, by sensing and statistically analysing some physiological signals of users experiencing Virtual Environments (VE). For this, a virtual building was designed considering the presence of stairs and ramps as architectural elements that could affect users´ physiological states and perception of fear of falling. Thirty-one older persons participated in this study and were assigned to two experimental conditions (i.e., safe and unsafe conditions). Five main locations (beginning of the stairs; neutral room; first descending ramp; ascending ramp; and the middle of ascending ramp) were considered along the participants' path, and heart rate (HR) was collected in the vicinity of those locations. Results shown significant differences in HR activation among neutral, beginning of stairs and middle of ascending ramp. Despite the fact that the effect of condition was not fully verified for HR, participants reported more fear while interacting with the unsafe condition, with significant differences between conditions.info:eu-repo/semantics/publishedVersio
Actinobacteria from arctic and atlantic deep-sea sediments—biodiversity and bioactive potential
The deep-sea covers over 70% of the Earth’s surface and harbors predominantly uncharacterized bacterial communities. Actinobacteria are the major prokaryotic source of bioactive natural products that find their way into drug discovery programs, and the deep-sea is a promising source of biotechnologically relevant actinobacteria. Previous studies on actinobacteria in deep-sea sediments were either regionally restricted or did not combine a community characterization with the analysis of their bioactive potential. Here we characterized the actinobacterial communities of upper layers of deep-sea sediments from the Arctic and the Atlantic (Azores and Madeira) ocean basins, employing 16S rRNA metabarcoding, and studied the biosynthetic potential of cultivable actinobacteria retrieved from those samples. Metabarcoding analysis showed that the actinobacterial composition varied between the sampled regions, with higher abundance in the Arctic samples but higher diversity in the Atlantic ones. Twenty actinobacterial genera were detected using metabarcoding, as a culture-independent method, while culture-dependent methods only allowed the identification of nine genera. Isolation of actinobacteria resulted on the retrieval of 44 isolates, mainly associated with Brachybacterium, Microbacterium, and Brevibacterium genera. Some of these isolates were only identified on a specific sampled region. Chemical extracts of the actinobacterial isolates were subsequently screened for their antimicrobial, anticancer and anti-inflammatory activities. Extracts from two Streptomyces strains demonstrated activity against Candida albicans. Additionally, eight extracts (obtained from Brachybacterium, Brevibacterium, Microbacterium, Rhodococcus, and Streptomyces isolates) showed significant activity against at least one of the tested cancer cell lines (HepG2 and T-47D). Furthermore, 15 actinobacterial extracts showed anti-inflammatory potential in the RAW 264.4 cell model assay, with no concomitant cytotoxic response. Dereplication and molecular networking analysis of the bioactive actinobacterial extracts showed the presence of some metabolites associated with known natural products, but one of the analyzed clusters did not show any match with the natural products described as responsible for these bioactivities. Overall, we were able to recover taxonomically diverse actinobacteria with different bioactivities from the studied deep-sea samples. The conjugation of culture-dependent and -independent methods allows a better understanding of the actinobacterial diversity of deep-sea environments, which is important for the optimization of approaches to obtain novel chemically-rich isolates.info:eu-repo/semantics/publishedVersio
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