Browsing by Issue Date, starting with "2022-11-04"
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- Influence of dolphin-watching tourism vessels on the whistle emission pattern of common dolphins and bottlenose dolphinsPublication . Silva, Ana Maria Conceição Alves da; Jesus, S. M.; Matos, Fábio Emmanuel Lopes deOver the last few years there has been a significant increase in the number of dolphin-watching boats in the Algarve (Portugal), which my lead to short- and long-term impacts on the target species (e.g., common dolphin, bottlenose dolphin). In recent decades there has been a greater interest in the potential effects of anthropogenic noise on marine mammals, given the important role that sound plays in the vital functions of these organisms. Several changes in the behavior and energy expenditure of cetaceans have been documented, including impacts in the vocalization parameters of dolphins, reduction in the communication range of whistles and increase energy expenditure. In this study, the whistles characteristics of common dolphin (Delphinus delphis) and bottlenose dolphin (Tursiops truncatus) were analyzed in the presence and absence of dolphin-watching tour boats to detect potential impacts in the vocalization of dolphins. Field recordings of common dolphin and bottlenose dolphin whistles were made from June to September 2022, using a calibrated system. Dolphin behavior and group size were recorded, as well as the number of boats in a 300 m radius. A total of 15h of acoustic recording was analyzed. Overall, these results showed a significant increase in start, low and high frequency on both species when exposed to the presence of one or more dolphin-watching tour vessels. However, when analyzing the whistles, it was possible to observe a reduction in the number of inflection points in the presence of the same vessels. These changes can be a dolphin strategy to avoid sound masking and increase of energy expenditure. These findings indicate that anthropogenic impact in the form of dolphin-watching tour vessels can influence the vocalization parameters of dolphins and such changes could have an impact if they reduce the communication range of whistles or increase energy expenditure.
- Molecular, morphological and chemical diversity of two new species of Antarctic Diatoms, Craspedostauros ineffabilis sp. nov. and Craspedostauros zucchellii sp. nov.Publication . Trentin, Riccardo; Moschin, Emanuela; Lopes, André Duarte; Schiaparelli, Stefano; L, Custódio; Moro, IsabellaThe current study focuses on the biological diversity of two strains of Antarctic diatoms (strains IMA082A and IMA088A) collected and isolated from the Ross Sea (Antarctica) during the XXXIV Italian Antarctic Expedition. Both species presented the typical morphological characters of the genus Craspedostauros: cribrate areolae, two “fore-and-aft” chloroplasts and a narrow “stauros”. This classification is congruent with the molecular phylogeny based on the concatenated 18S rDNArbcL-psbC alignment, which showed that these algae formed a monophyletic lineage including six taxonomically accepted species of Craspedostauros. Since the study of the evolution of this genus and of others raphe-bearing diatoms with a “stauros” is particularly challenging and their phylogeny is still debated, we tested alternative tree topologies to evaluate the relationships among these taxa. The metabolic fingerprinting approach was implemented for the assessment of the chemical diversity of IMA082A and IMA088A. In conclusion, combining (1) traditional morphological features used in diatoms identification, (2) phylogenetic analyses of the small subunit rDNA (18S rDNA), rbcL and psbC genes, and (3) metabolic fingerprint, we described the strains IMA082A and IMA088A as Craspedostauros ineffabilis sp. nov. and Craspedostauros zucchellii sp. nov. as new species, respectively
- Toxin profile of two Gymnodinium catenatum strains from Iberian Coastal WatersPublication . Leal, Joana F.; Bombo, Gabriel; Pereira, Hugo; Vicente, Bernardo; Amorim, Ana; Cristiano, Maria L. S.Gymnodinium catenatum has been the main species responsible for paralytic shellfish poisoning events along the Portuguese coast (Iberian Peninsula), causing bans on bivalve harvesting that result in huge economic losses. This work presents the characterization of two novel isolates of G. catenatum regarding their growth and toxin profiles. Laboratory growth experiments revealed that, although low growth rates were obtained during cultivation, the cell yields were high compared to those reported in the literature. Evaluation of the toxin profiles, by HPLC-FLD, essentially confirmed the typical composition of toxins of this regional population (Iberian Peninsula), namely, the absence or low representation of the toxins dcNEO, GTX1,4 and NEO and a higher ratio of the toxins C1,2, GTX6 and GTX5. However, the percentage of the identified toxins varied among the strains of this study (under the same isolation, growth, and analysis conditions), and also differed from that of other strains described in the literature. Interestingly, we found a comparatively high abundance of dcSTX in both strains, relative to the other toxins, and an unquantifiable amount of C3,4 toxins. In addition to the geographic relationship between toxin profiles, chemical conversions among toxins may explain some differences encountered in the toxin profiles of G. catenatum strains.
- A framework for emotion and sentiment predicting supported in ensemblesPublication . Novais, Rui Miguel Boneco; Cardoso, Pedro J. S.; Rodrigues, J. M .F.Humans are prepared to comprehend each other’s emotions through subtle body movements or facial expressions; using those expressions, individuals change how they deliver messages when communicating between them. Machines, user interfaces, or robots need to empower this ability, in a way to change the interaction from the traditional “human-computer interaction” to a “human-machine cooperation”, where the machine provides the “right” information and functionality, at the “right” time, and in the “right” way. This dissertation presents a framework for emotion classification based on facial, speech, and text emotion prediction sources, supported by an ensemble of open-source code retrieved from off-the-shelf available methods. The main contribution is integrating outputs from different sources and methods in a single prediction, consistent with the emotions presented by the system’s user. For each different source, an initial aggregation of primary classifiers was implemented: for facial emotion classification, the aggregation achieved an accuracy above 73% in both FER2013 and RAF-DB datasets; For the speech emotion classification, four datasets were used, namely: RAVDESS, TESS, CREMA-D, and SAVEE. The aggregation of primary classifiers, achieved for a combination of three of the mentioned datasets results above 86 % of accuracy; The text emotion aggregation of primary classifiers was tested with one dataset called EMOTIONLINES, the classification of emotions achieved an accuracy above 53 %. Finally, the integration of all the methods in a single framework allows us to develop an emotion multi-source aggregator (EMsA), which aggregates the results extracted from the primary emotion classifications from different sources, such as facial, speech, text etc. We describe the EMsA and results using the RAVDESS dataset, which achieved 81.99% accuracy, in the case of the EMsA using a combination of faces and speech. Finally, we present an initial approach for sentiment classification.
- Scoping challenges and opportunities presented by COVID-19 for the development of sustainable short food supply chainsPublication . Baptista, Nuno; Alves, Helena; Matos, NelsonOver the past decades, short food supply chains attracted government and public support owing to their potential to mitigate some of the sustainability issues associated with the conventional globalized food supply system. The recent event of the coronavirus disease pandemic placed unprecedented pressure on food supply systems worldwide, and it constitutes a unique opportunity to evaluate the performance of food chains. Through a scoping review of the academic literature, this study provides a critical assessment of the implications of the pandemic on short food supply chains in multiple economies. Following the guidelines outlined in the PRISMA-ScR framework, the SCOPUS and ISI Web of Science databases were searched for the academic literature on the topic. The results of the review indicate that, besides the direct effects of the pandemic, the indirect effects resulting from public policies implemented to contain the spread of the virus affected all relevant dimensions of sustainability. Moreover, the consequences of the pandemic were more disruptive in the short food chains of low-income countries than in those of high-income countries. The main challenges and opportunities for the sustainable development of short food supply chains are identified, and recommendations for future research are outlined.
- Plano estratégico de marketing digital para o blogue Bookish Girl Around The WorldPublication . Magalhães, Carla Filipa Rodrigues; Santos, Margarida C.; Machado, CarlaSolo travel é um nicho de mercado turístico que se tem vindo a tornar uma tendência e com um crescente número de praticantes. Os blogues são considerados uma das ferramentas mais importantes de inbound marketing para influenciar na escolha de um tipo de turismo a praticar. Assim, esta dissertação teve como principal objetivo a apresentação de um plano estratégico de marketing digital para um blogue de viagens focado no nicho de mercado solo travel feminino. De modo a atingir este objetivo, foi realizada uma pesquisa qualitativa exploratória nas temáticas do marketing, blogues de viagem e solo travel, conceitos estes fundamentais para a contextualização deste projeto. O plano estratégico de marketing digital foi desenvolvido com base na estrutura sugerida por Westwood (2016) e a adaptação do mesmo à componente digital foi efetuada baseando-se no plano de Alford e Page (2015). Assim, o plano estratégico de marketing digital apresentado foi dividido em 2 secções: a auditoria e a estratégia. Dentro da fase da auditoria, analisaram-se os fatores da macroenvolvente e microenvolvente, desde o mercado até ao consumidor e à concorrência direta. Relativamente à estratégia de marketing, definiram-se os objetivos, a segmentação e targeting, o posicionamento e as políticas de produto, preço, distribuição e comunicação. Na auditoria concluiu-se que ao contrário dos blogues de solo travel masculinos, os direcionados para o público feminino são escassos, existindo apenas três focados neste nicho. Quanto à estratégia a seguir, definiu-se que para o blogue se poder diferenciar deverá focar-se nos constrangimentos que as mulheres enfrentam durante uma viagem e como ultrapassá-los.
- Scar-free healing: acomys cahirinus, a model of mammalian regenerationPublication . Domingues, Adriana da Costa Anselmo; Vitorino, Marta; Simão, SóniaRegeneration is the capacity that some organisms present to regrow tissues, appendages or even organs without scar and with full functionality. This capacity is present mostly in invertebrates and lower vertebrates such as some fish and lizards, but not in mammals. Spiny mice (Acomys spp.) are a non-traditional rodent model that possess a number of interesting characteristics. This rodent is currently gaining attention as a tissue regeneration model. While most mammals repair wounds by fibrotic scarring, Acomys can mount a regenerative response to wounding of several organs and tissues, including skin, ear and musculoskeletal tissue. In this manuscript, it was done a compilation and an extensive review of the Acomys regeneration literature published in the last decade. It is described all the information available about the characteristics and mechanisms that lead to regeneration in this animal model. In conclusion, until now was described that Acomys is able to regenerate several organs and tissues such as ear, skin, skeletal muscle and spinal cord. The regeneration of these several tissues has some common features and other that are specific for each tissue. It is described that a mild immune system present in Acomys allows the regeneration of all this tissues. Moreover, it is also thought that this ability is due to macrophage response, lack of fibrosis and myofibroblasts production and Hippo-Yap signalling regulation. Regarding the heart and kidney, the regeneration of this tissues was never showed, however these organs are more resistant to injury and are able to regain function after injury. With this animal model, the scientific community will try to unveil the mechanisms behind regeneration and, in the future, following the hypothesis that regenerative mechanisms are conserved throughout the vertebrates, they could then extrapolate these finding to develop therapies for humans.