Browsing by Issue Date, starting with "2023-07-26"
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- A global overview of dietary supplements: Regulation, market trends, usage during the COVID-19 Pandemic, and health effectsPublication . Djaoudene, Ouarda; Romano, Anabela; Bradai, Yasmine Djedjiga; Zebiri, Feriel; Ouchene, Amina; Yousfi, Yasmine; Amrane-Abider, Meriem; Sahraoui-Remini, Yasmine; Madani, KhodirOver the last 20 years, the use of dietary supplements (DS) has continued to grow in many countries. Due to the public health crisis brought on by the COVID-19 pandemic and amidst fears regarding COVID-19 vaccines and their low supply in many regions of the world, there has been a marked interest in the use of DS as alternative means of protecting against and treating this emerging disease, as well as boosting the immune system and minimizing the risk of inflammation. Despite a lack of evidence to suggest their efficacy, a surge in the sales of DS has been reported in many parts of the world. Questions have also been raised about the health effects associated with DS due to their increased use during the health crisis. Numerous scientific studies have demonstrated their beneficial properties as well as some adverse and even toxic effects. In addition, given the current global interest in this issue, a review is needed to establish the status of dietary supplements before and during the health crisis. The aim of this review is to summarize the current evidence on the impact of dietary supplements on the incidence of the COVID-19 pandemic, as well as their regulation and associated market trends. First, we provide an overview of DS, including a comprehensive review of the legislative and regulatory aspects of DS in the USA, China, the EU, and Algeria. Second, we describe the prevalence of the most commonly consumed DS and their efficacy as a prophylactic modality in the era of COVID-19. Additionally, we examine the structure and size of the DS market in the countries that predominantly produce and import them, its global market trend, and the impact of the COVID-19 pandemic on market growth. Finally, in this review, we also discuss the profile of DS users.
- Growth and mortality of microbial plankton in the Ria Formosa coastal lagoonPublication . Santos, Yohann dos; Domingues, Rita; Galvão, Helena M.Microbial plankton components interact with each other through fluxes of matter and energy, forming a complex microbial food web. It is well recognized that mortality due to viral lysis and grazing by phagotrophic protists are important processes of biomass removal of heterotrophic prokaryotes and phytoplankton. Since there are only a few studies addressing microbial mortality due to grazing in the Ria Formosa coastal lagoon and the contribution of viruses to prokaryote mortality was never addressed in this ecosystem, the main objective of this study was to evaluate growth and mortality of heterotrophic prokaryotes and phytoplankton in the Ria Formosa coastal lagoon, in order to discuss the quantitative trophic role of microzooplankton and viruses in microbial food web of this important ecosystem. The dilution technique was used to evaluate the impact of microzooplankton on microbial populations of the Ria Formosa coastal lagoon; to estimate the contribution of viruses to heterotrophic prokaryote mortality, modified dilution experiments were also performed. The dilution experiments revealed notable seasonal variations in the growth and grazing rates of heterotrophic prokaryotes and phytoplankton community, with mean grazing rates of 1.66 d-1 and 0.106 d-1 respectively, slightly higher than their mean potential instantaneous growth rate (1.57 d-1 and 0.080 d-1, respectively). These results suggest that microzooplankton consume a significant proportion of heterotrophic prokaryotes and phytoplankton community in the Ria Formosa coastal lagoon. Regarding specific phytoplankton groups, eukaryotic picophytoplankton and cryptophytes showed higher average grazing rates, whereas eukaryotic picophytoplankton showed higher average potential instantaneous growth rates; a wide range of grazing rates among phytoplankton groups is suggestive of selectivity of grazers among taxa and highlights the need to consider and analyze the specific dynamics of each phytoplankton group separately in future studies. On the other hand, this study revealed that viral lysis is a significant source of mortality in late-summer autumn, even exceeding the grazing rates of microzooplankton. Considering the relevance of the Ria Formosa, future studies should focus on these mortality factors, as well as to predict the effects of climate change, and its associated impacts, on these important biomass removal processes.
- Estudo de sistemas de isolamento térmico em tanque de piscinasPublication . Segura, Maria Camila Narvaez; Oliveira, Miguel José; Farinha, FátimaAs piscinas exteriores aquecidas envolvem consumos de energia muito elevados, pelo que, encontrar soluções que permitam minimizar as perdas de energia através da envolvente e, em particular, pelo tanque, contribuirá de forma decisiva para a sustentabilidade destes equipamentos. A presente dissertação tem por base o estudo de um sistema inovador de isolamento térmico pelo interior do tanque, com elevada durabilidade e manutenção reduzida, que permita diminuir as perdas de energia e consequentemente, as necessidades de aquecimento da água. O sistema em estudo explorou um conceito semelhante ao ETICS - External Thermal Insulation Composite Systems, frequentemente aplicado na envolvente exterior de paredes de edifícios com o propósito da melhoria do seu desempenho térmico, mas no caso das piscinas com reservas do ponto de vista do impacto a nível de estabilidade mecânica e por inerência da capacidade de impermeabilização nas piscinas. O trabalho levado a efeito consistiu em estudos laboratoriais referentes a sistemas que incorporam placas de isolamento de diferentes materiais (face de avaliação e seleção do material), bem como a campanha experimental realizada no protótipo e em paredes de teste com placas de isolamento térmico ICB (Insulation Cork Board). Verificou-se que a solução desenvolvida apresenta resultados promissores no que respeita à capacidade de impermeabilização à água sob pressão, suscetibilidade à fissuração, resistência ao impacto e também no que se refere à resistência à aderência. Nesta fase, os resultados obtidos evidenciam um comportamento adequado face ao desempenho pretendido.
- Improving fisheries management through spatio-temporal analysis of catches, discards, fishing effort and selectivity, across different métiersPublication . Szynaka, Monika; Karim, Erzini; Gonçalves, Jorge; Campos, AidaI would first like to thank my advisers, especially Dr. Karim Erzini for helping me with the project change during the first of the PhD and for overall support since the beginning of my master’s project. I deeply admire your passion for fisheries research and the number of hours you have spent reviewing my writing. Thank you to Dr. Aida Campos for giving me an opportunity to expand my horizons in fisheries when I joined the TecPescas project and for support in and outside the PhD. Thank you to Dr. Jorge Gonçalves for the local support during the PhD, especially for helping me learn how to take care of the financial side of science. Finally, a thank you to Dr. Svein Løkkeborg in Norway for the original opportunity to collaborate with him prior to my change in the project and for the support during writing my first review. Thank you to all the fishers I worked with, and we interviewed for giving me the data that I needed to complete this PhD. A special thanks to the captain and crew of Mar Vivo, for a very wild experience on the sea and delicious fresh lunches. And to the captain and crew of Bartolomeu who worked with us on the trammel net project as I thoroughly enjoyed the dinners that I received from them and due to all of them being extremely friendly. A thank you to all my colleagues who worked with me at various periods of the PhD. Without your support I could not have finished my work. Thank you to Mariana Fernandes, Ana Marçalo and especially Pedro Monteiro for helping me grow as a researcher from the master’s until now. Thank you to all the people of Fisheries, Biodiversity and Conservation lab for all the help, for creating a general environment of friendliness and for making time to chat. Thank you so much to all my friends and to my husband that have also been there for me throughout the PhD. From getting coffees in the morning, to lunches in the afternoon, to those who were there from the beginning and to those I met later in the PhD program, as well as those who I’ve known from 6 to 15 years and have supported my dreams in science. Thank you to my parents who have supported my journey in science since I decided I was going to do a PhD in marine biology when I was only 13 years old. Thank you for the sacrifices you both made and for being role models in what hard and efficient work can mean, as well as taking pride in your work. Thank you to my sister who has been my cheerleader through the past years and especially during my periods of struggle, I am extremely thankful to have a sibling who cares so much to see me succeed. Thank you to my grandma for getting on skype almost every weekend and to my grandpa for making me laugh. (PL: Dziękuję mojej babci za to, że prawie w każdy weekend wchodziła na skype i słuchała mnie i mojemu dziadkowi za rozśmieszenie mnie.) Fishers in the Southern Portuguese multi-gear coastal fleet own licenses for a variety of fishing gears including static nets, longlines, and traps, and dredges. Information on the fishing gear being actively used is scarce and most vessels are not required to report geographic location, making the impact of the local environment difficult to evaluate. The first and main objective of this thesis was to identify métiers in the multi-gear coastal fisheries operating in the Portuguese south coast, including the type of gear being used to target specific species or assemblages in certain areas during a specific time of year in a three-step process. The first step was a review to understand the definition of fisheries métiers using static longlines due to their well-defined target species, little environmental impacts, and various characteristics that can be modified for improved fishing. This was followed by a cluster analysis on landing profiles for the fleet (2012-2016), followed by the second and third step in which validations using questionnaires and onboard observations, respectively. The main finding was the application of a low-cost analysis to identify métiers within a multi-gear fleet with limited data, and specific to this fleet, an increasing number of vessels active within the octopus (Octopus vulgaris) trap métier. The second objective was to assess a proposed raised trammel net (by insertion of a section referred to as “aranha”) to reduce by-catch and habitat impacts in the cuttlefish (Sepia officinalis) trammel net fishery. The results were promising as the modified net caught significantly less habitat forming organisms and similar target species’ amounts as the standard net. The results presented in this thesis can contribute to the management of this multi-gear fleet by presenting the necessary information to make decisions, especially for métiers with high number of vessels, and effort in highlighting the necessity for gear modifications in areas where the habitat is impacted.