Artigos em revistas internacionais
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- The collapse of Silicon Valley Bank and Credit Suisse and their impact on other U.S. BanksPublication . Martins, António Miguel; Martins, AntónioABSTRACT This paper examines how US banking industry responded to the collapse of Silicon Valley Bank and Credit Suisse. The analysis of abnormal returns surrounding the announcement of the collapse of Silicon Valley Bank and Credit Suisse reveals a negative and statistically significant impact on the largest listed US banks. Banks’ market value loss is explained by information asymmetries and uncertainty returns, systemic contagion, and panic. These reactions are reinforced or mitigated by bank-specific characteristics such as size, liquidity, profitability, risk aversion, operational efficiency, institutional ownership, internationalization, dependence on uninsured deposits and ratio of off balance sheet items.
- Trends in airborne grass pollen in Évora City (Portugal)Publication . Elsa, Rute Guerra Caeiro; Camacho, Roberto Alexandre Pisa; Ferreira, Manuel Branco; Pedro Carreiro-Martins; Camacho, Irene Gomes Câmara; Camacho, Irene; Camacho, RobertoAbstractAerobiology could be used as complementary data or proxy for studying phenology, especially in species which usually are not long-distance transported, such as grasses. This 21-year aerobiological study took place in Évora (South Portugal), using a seven-day recording volumetric pollen trap with the aim of analysing the temporal trends of grass pollen seasons. To this end, data were statistically tested for correlation and regression to determine the features and temporal trends of pollen seasons. Main results show that Poaceae pollen has a high representation in pollen spectrum, 20% (min: 7%; max: 44%), with a long season starting in March and lasting till August/September or October. There was an overall, but not statistically significant trend, towards an increase in the annual pollen integral and peak values, and also an overall non-statistically significant trend towards an earlier start and later end of the pollen season. Main and high pollen seasons have been lasting longer, and the days with allergenic potential have been rising in line with the local temperature rising trend. It seems that grass pollen production is being aided by warmer temperatures and increased grassland areas in Alentejo region. This could promote the increase in annual pollen levels and in the number of high pollen days over the years. In clinical terms, it means that grass allergic patients are exposed to longer periods of airborne pollen and to higher counts over a longer time. The climate conditions projected for Alentejo region, including rising temperature, and the changes in local grassland areas may help to clarify the trends of grass pollen seasons in the next decades.
- Redefining entrepreneurship: philosophical insights in a post-individualist eraPublication . Leite, Eduardo Manuel de Almeida; Audretsch, David; Leite, AnaIn the dynamic landscape of post-individualist entrepreneurship, this study delves into the profound interplay between philosophy and entrepreneurship. Guided by foundational philosophical tenets, including Spinoza’s ‘conatus’ and ‘affects’, Schopenhauer’s asceticism, and Nietzsche’s diverse perspectives, their implications for modern entrepreneurship are dissected. Employing a critical and analytical approach, the convergence and divergence between philosophy and entrepreneurship are explored. The methodology integrates philosophical works, entrepreneurship theories and social network concepts to unveil fresh insights into contemporary entrepreneurial behaviour. This study not only identifies significant resonances between these philosophical underpinnings and entrepreneurship but also confronts the challenges posed by philosophical contrasts. For instance, while Spinoza’s concept of ‘conatus’ resonates with the entrepreneurial drive for innovation and perseverance, Schopenhauer’s asceticism introduces a contrasting perspective, questioning the sustainability of entrepreneurial desires in the face of materialism and temporary gains. This juxtaposition challenges individuals to reevaluate the essence of entrepreneurial success, suggesting that it extends beyond mere financial gain to include deeper satisfaction and a more meaningful purpose that transcends fleeting desires. The study’s results offer tangible benefits for entrepreneurs, illuminating the emotional complexities, ethical implications and the intricate dynamics within entrepreneurial networks.
- Machine learning system for commercial banana harvestingPublication . Hayat, Ahatsham; Baglat, Preety; Mendonça, Fábio; Mostafa, Sheikh Shanawaz; Dias, Fernando Morgado; Baglat, Preety; Silva Mendonça, Fábio Rúben; Morgado-Dias, FernandoAbstract The conventional process of visual detection and manual harvesting of the banana bunch has been a known problem faced by the agricultural industry. It is a laborious activity associated with inconsistency in the inspection and grading process, leading to post-harvest losses. Automated fruit harvesting using computer vision empowered by deep learning could significantly impact the visual inspection process domains, allowing consistent harvesting and grading. To achieve the goal of the industry-level harvesting process, this work collects data from professional harvesters from the industry. It investigates six state-of-the-art architectures to find the best solution. 2,685 samples were collected from four different sites with expert opinions from industry harvesters to cut (or harvest) and keep (or not harvest) the banana brunch. Comparative results showed that the DenseNet121 architecture outperformed the other examined architectures, reaching a precision, recall, F1 score, accuracy, and specificity of 85%, 82%, 82%, 83%, and 83%, respectively. In addition, an understanding of the underlying black box nature of the solution was visualized and found adequate. This visual interpretation of the model supports human expert’s criteria for harvesting. This system can assist or replace human experts in the field.
- Ionization layer with collision-free atoms at the edge of partially to fully ionized plasmasPublication . Benilov; Benilov, MikhailAbstract When a hot arc spot has just formed on the cathode surface, e.g. in the course of arc ignition on a cold cathode, a significant part of the current still flows in the glow-discharge mode to the cold surface outside the spot. The near-cathode voltage continues to be high at all points of the cathode surface. The mean free path for collisions between the atoms and the ions within the plasma ball near the spot is comparable to, or exceeds, the thickness of the ionization layer, which is a part of the near-cathode non-equilibrium layer where the ion current to the cathode is generated. The evaluation of the ion current to the cathode surface under such conditions is revisited. A fluid description of the ion motion in the ionization layer is combined with a kinetic description of the atom motion. The resulting problem admits a simple analytical solution. Formulas for the evaluation of the ion current to the cathode for a wide range of conditions are derived and the possibilities of using these formulas to improve the accuracy of existing methods for modeling high-pressure arc discharges in relation to glow-to-arc transitions are discussed.
- Model of non-equilibrium near-cathode plasma layers for simulation of ignition of high-pressure arcs on cold refractory cathodesPublication . Santos, D. F. N.; Almeida, N. A.; Benilova, L. G.; Benilov, M; Santos, Diego; Benilov, MikhailAbstract The introduction of secondary ion-electron emission into an approximate model of non-equilibrium plasma layers on hot (thermionic) cathodes of high-pressure arc discharges allows extending the model to low cathode surface temperatures. Analysis of evaluation results shows that the extended model describes glow-like discharges on cold cathodes and thermionic arc discharges on hot cathodes, as it should. In the course of glow-to-arc transitions on cold cathodes, a transient regime occurs where a hot arc spot has just formed and a significant fraction of the current still flows to the cold surface outside the spot, so that the near-cathode voltage continues to be high. The power input in the near-cathode layer is very high in this regime, and so is the electron temperature in the near-cathode region. The mean free path for collisions between the atoms and the ions in these conditions exceeds the thickness of the layer where the ion current to the cathode is generated. A new method for evaluation of the ion current under such conditions is implemented. The developed model is applicable for cathode surface temperatures below the boiling point of the cathode material and may be used for multidimensional simulations of ignition of high-current arcs on refractory cathodes.
- The relationship between healthcare satisfaction after miscarriage and perinatal grief symptoms: a cross-sectional study on Portugal residentsPublication . Mendes, Diana C. G.; Fonseca, Ana; Cameirão, Mónica S.; Cameirão, MónicaObjective: 15–20% of identified pregnancies result in miscarriage, which may lead to persistent symptoms of psychological morbidities in some women. Healthcare satisfaction is among the factors believed to influence such negative psychological responses. Here, we present the results of a study conducted in Portugal that analyzes the relationship between healthcare satisfaction, information and support provision and perinatal grief symptoms. Methods: In a cross-sectional study, symptoms of perinatal grief, degree of satisfaction with healthcare received, and information and support provision data were collected through an online survey aimed at women in Portugal who suffered a miscarriage. 873 were considered eligible. Correlations were performed between perinatal grief scores and healthcare satisfaction rates. Finally, the proportions of information and support received were compared after distributing the sample in groups according to their perinatal grief levels. Results: Healthcare satisfaction correlated significantly with perinatal grief scores, the latter increasing as satisfaction levels decreased. 61.1% of our sample received information about the physical consequences of miscarriage and showed a significantly lower rate of above-threshold perinatal grief symptoms in this group. 18.2% received information about its mental health consequences, with no significant differences in above threshold symptom rates. 11.7% were offered or recommended mental health support, but no significant dif ferences in above-threshold symptom rates were found. Conclusion: Healthcare satisfaction and information on after-miscarriage physical changes correlated significantly with reduced perinatal grief rates after miscarriage. However, any effects of mental health information and psychological support provision need further studies. Training for healthcare providers dealing with pregnancy loss, implementing national guidelines that include follow-up on the parents’ physical and psychological health, and including a specialized area in medical structures are advised.
- Sustainable synthesis of bionanomaterials using non-native plant extracts for maintaining ecological balance: a computational bibliography analysisPublication . Jeevanandam, Jaison; Rodrigues, João; Rodrigues, Joãolternative approach to synthesizing less or nontoxic nanomaterials, compared to conventional physical and chemical approaches. Among these biological methods, plant-mediated approaches (phytosynthesis) are reported to be highly beneficial for large-scale, nontoxic nanomaterial synthesis. However, plant-mediated synthesis of nanomaterials using native plant extract can lead to bioprospecting issues and deforestation challenges. On the other hand, non-native or invasive plants are non-indigenous to a particular geographic location that can grow and spread rapidly, ultimately disrupting the local and endogenous plant communities or ecosystems. Thus, controlling or eradicating these non-native plants before they damage the ecosystem is necessary. Even though mechanical, chemical, and biological approaches are available to control non-native plants, all these methods possess certain limitations, such as environmental toxicity, disturbance in the nutrient cycle, and loss of genetic integrity. Therefore, non-native plants were recently proposed as a novel sustainable source of phytochemicals for preparing nanomaterials via green chemistry, mainly metallic nanoparticles, as an alternative to native, agriculture-based, or medicinal plants. This work aims to cover a literature gap on plant-mediated bio nanomaterial synthesis with an overview and bibliography analysis of non-native plants via novel data mining and advanced visualization tools. In addition, the potential of non-native plants as a sustainable, green chemistry-based alternative for bionanomaterial preparation for maintaining ecological balance, the mechanism of formation via phytochemicals, and their possible applications to promote their control and spread were also discussed. The bibliography analysis revealed that only an average of 4 articles have been published in the last 10 years (2013–2023) on non-native/invasive plants for nanomaterial synthesis, which shows the significance of this article.
- Comparative analysis of antioxidant and fatty acid composition in avocado (Persea americana Mill.) fruits: exploring regional and commercial varietiesPublication . Gonçalves, David; Gouveia, Carla S. S.; Ferreira, Maria J.; Ganança, José F. T.; Pinto, Diana C. G.; Carvalho, Miguel A. A. Pinheiro de; Ganança, José Filipehytochemical and biochemical properties. Aiming to evaluate the antioxidant quality and fatty acid composi tion with a commercial avocado, flours were obtained from five varieties (four regional and one commercial Hass) across different tissues (pulp and by-products) and cycles (years and on-tree maturation stages). Results showed that a regional variety with thin purple skin had the highest antioxidant qualities and lipid content, surpassing the other regional and commercial Hass varieties. Oleic acid prevailed in all samples, with regional avocados containing arachidonic acid which is an uncommon occurrence among higher plants. Variations in fatty acid content were influenced by the timing of harvest. These outcomes highlight the promising potential of avocados from Madeira Island.
- The allergenic potential of green urban areas in the Macaronesian islands: the case of Funchal City (Madeira)Publication . Camacho, Irene; Macías-de-la-Rosa, Álvaro; Camacho, Roberto; Agnieszka Grinn-Gofroń; Cariñanos, PalomaPublic gardens are elements that constitute the urban green infrastructure. Such units provide ecosystem services that are becoming a key concern in urban planning strategies. In this survey the allergenic potential of two public gardens in Funchal, a city exhibiting sub tropical and Mediterranean climatic features, was assessed. Different allergenic risk scenarios were considered, and the Allergenicity Indexes recalculated. Results show that the Municipal Garden exhibits an IUGZA (Index of Urban Green Zone Allergenicity) of 0,39 and Santa Catarina Park an IUGZA of 0,16, which are considered spaces of moderate and low allergenicity level, respectively. Among the tested scenarios that could aggravate the IUGZA values, the worst would be an extension of the pollen season for all species. This might represent an issue considering the overall trend towards an earlier start and later end of the pollen season from important allergenic plants in Europe. The assessment of the IUGZA should include all plant biotypes of an urban green area in subtropical regions as they allow us to infer more precisely on the real risk population is exposed to. It seems that increasing species diversity can improve the allergenic indexes, but novel invasive species should be studied to assess their allergenicity level.