1,412 research outputs found
Hydrology and biota interactions as driving forces for ecosystem functioning
This chapter examines the interactions between biologic and hydrologic processes in estuarine and nearshore coastal ecosystems, and their relevance to ecosystem functioning. The role of specific hydrologic variables and processes upon key functional groups of organisms (phytoplankton, heterotrophic bacteria, holozooplankton, merozooplankton, benthos, and nekton) is addressed considering both bottom-up and top-down effects. The impact of biologic processes on relevant hydrologic features, including dissolved gases, inorganic nutrients, organic matter, chemical and biological contaminants, turbidity, and water flow, is then evaluated. Biologic-and hydrologic-driven changes are integrated, specifying how they reverberate into ecosystem functioning over different spatial and temporal scales
Co-limitation of phytoplankton by N and P in a shallow coastal lagoon (Ria Formosa): implications for eutrophication evaluation
The Ria Formosa coastal lagoon is a highly productive shallow ecosystem in southern Portugal, subjected to nutrient inputs from anthropogenic and natural sources. Nutrients are major abiotic drivers of phytoplankton in this system, but their effects on phytoplankton assemblages and the occurrence of nutrient limitation are still poorly understood. The main goal of this study was, thus, to evaluate the occurrence, type, and effects of nutrient limitation on phytoplankton community and specific functional groups in the Ria Formosa coastal lagoon. We conducted nutrient enrichment experiments with factorial additions of nitrogen (N) and phosphorus (P) using natural phytoplankton assemblages from distinct locations in the Ria Formosa, throughout a yearly cycle. Phytoplankton composition and abundance were evaluated using inverted and epifluorescence microscopies, and spectrophotometric methods were used for biomass. Limitation was defined as higher phytoplankton growth following enrichment with a particular nutrient in relation to the non-enriched control. The most common type of phytoplankton limitation was simultaneous co-limitation by N and P; diatoms, as r-strategists, were the most frequently limited group. Single N and P limitation, and serial P limitation were also observed, as well as negative responses to nutrient enrichment. Group-specific responses to nutrient enrichment were not reflected in the relative abundance of phytoplankton groups within the whole assemblage, due to the numerical dominance of pico-sized groups (cyanobacteria and eukaryotic picophytoplankton). Ambient nutrient ratios and concentrations did not predict phytoplankton nutrient limitation, given the different nutrient utilisation traits among phytoplankton functional groups. Therefore, nutrient ratios should not be used as indicators of nutrient limitation in eutrophication assessment.LA/P/0069/2020info:eu-repo/semantics/publishedVersio
River damming leads to decreased phytoplankton biomass and disappearance of cyanobacteria blooms
The large Alqueva dam was built in the early 2000s in the Guadiana River (southern Portugal) and has
highly controlled the freshwater flowing into the Guadiana estuary, leading to significant changes in the
natural hydrological regime. To evaluate the impacts of water restriction and flow regularization on
estuarine phytoplankton and their environmental variables, sampling campaigns were conducted in the
Guadiana estuary throughout a 14-year period, covering different phases related to the Alqueva dam
construction. Significant alterations in phytoplankton and their environmental drivers were observed. In
the post-filling period, river flow became more constant throughout the year and its natural seasonal
variability, with maxima in the winter and minima in the summer, was greatly reduced, leading to higher
river flows in the summer and lower in the winter, in relation to the pre-filling phase. Nutrient and light
availability and, hence, phytoplankton dynamics, were greatly affected. Phytoplankton abundance and
biomass decreased in the post-filling phase related to a decrease in diatoms and cyanobacteria. Since
cyanobacteria blooms in the Guadiana are frequently dominated by toxic species, this constitutes an
improvement in water quality. However, the overall decrease in phytoplankton biomass and, specifically,
the decline in diatom biomass, will have major consequences for the higher trophic levels that depend on
planktonic food
Estrutura e dinâmica da teia alimentar microbiana na Ria Formosa
Tese dout., CiĂŞncias do Mar, Universidade do Algarve, 2006BD/762/90-IGJunta Nacional de Investigação CientĂfica e TecnolĂłgica (JNICT
Education and cultural and artistic developrnent
O texto aborda o papel da Educação no desenvolvimento cultural, possibilitando o exercĂcio da capacidade de perceber, conviver e valorizar diferentes cĂłdigos culturais. Procura-se distinguir os conceitos de Diversidade Cultural, Multiculturalidade. Interculturalidade e Ecologia Cultural. O papel das Artes para o desenvolvimento cultural Ă© analisado, considerandose seus efeitos para o desenvolvimento da consciĂŞncia de cidadania, para a alfabetização visual, para a potencialização da criatividade e para a preparação de um pĂşblico apreciador de arte. Questões de mĂ©todos de ensino da Arte sĂŁo discutidas distinguindo-se os mĂ©todos modernistas e pĂłs-modernistas.The text afirms the importance of education for cultural development and discusses problems of Cultural Literacy, Cultural identity and Cultural ecology in the context of the Third World and of the european and white north american codes.The text is concerned with conceptual distintions among Cultural Diversity, Multiculturality, Pluriculturality and Interculturality. The role of the arts for cultural development of citzenship's consciousness, of creativity and of visual literacy are pointed out. Finaly questions of methods of Art Teaching are discussed, specially the Modernist and Post Modernist methods
Patterns and predictors of phytoplankton assemblage structure in a Coastal Lagoon: Species-specific analysis needed to disentangle anthropogenic pressures from ocean processes
Phytoplankton are dominant primary producers and key indicators in aquatic ecosystems. Understanding the controlling factors on the structure of phytoplankton assemblages is fundamental, but particularly challenging at the land–ocean interface. To identify the patterns and predictors of phytoplankton assemblage structure in the Ria Formosa coastal lagoon (south Portugal), this study combined phytoplankton abundance along a transect between the discharge point of a wastewater treatment plant and a lagoon inlet, over two years, with physico-chemical, hydrographic, and meteo-oceanographic variables. Our study identified 147 operational taxonomic units (OTUs), and planktonic diatoms (60–74%) and cryptophyceans (17–25%) dominated the phytoplankton in terms of abundance. Despite strong lagoon hydrodynamics, and the lack of spatial differences in the phytoplankton abundance and most diversity metrics, the multivariate analysis revealed differences in the assemblage structure between stations (p < 0.001) and seasons (p < 0.01). Indicator analysis identified cryptophyceans as lagoon generalists, and 11 station-specific specialist OTUs, including Kryptoperidinium foliaceum and Oscillatoriales (innermost stations) and potentially toxigenic species (Pseudo-nitzschia and Dinophysis; outer lagoon station, p < 0.05). Water temperature, pH, and nutrients emerged as the variables that best explained the changes in the phytoplankton assemblage structure (p < 0.001). Our findings provide insight into the relevance of local anthropogenic and natural forcings on the phytoplankton assemblage structure and can be used to support the management of RF and other coastal lagoons.MAR-01.04.02-FEAMP-0003info:eu-repo/semantics/publishedVersio
Cardiovascular dysfunction in obesity and new diagnostic imaging techniques: the role of noninvasive image methods
Obesity is a major public health problem affecting adults and children in both developed and developing countries. This condition often leads to metabolic syndrome, which increases the risk of cardiovascular disease. A large number of studies have been carried out to understand the pathogenesis of cardiovascular dysfunction in obese patients. Endothelial dysfunction plays a key role in the progression of atherosclerosis and the development of coronary artery disease, hypertension and congestive heart failure. Noninvasive methods in the field of cardiovascular imaging, such as measuring intima-media thickness, flow-mediated dilatation, tissue Doppler, and strain, and strain rate, constitute new tools for the early detection of cardiac and vascular dysfunction. These techniques will certainly enable a better evaluation of initial cardiovascular injury and allow the correct, timely management of obese patients. The present review summarizes the main aspects of cardiovascular dysfunction in obesity and discusses the application of recent noninvasive imaging methods for the early detection of cardiovascular alterations
JOICE LEAL E RICO LINS
Contexto Ă guisa de resumo A disciplina de HistĂłria do Ensino da Arte e do Design no contexto da contemporaneidade foi ministrada por mim, Ana Mae Barbosa, no Programa de PĂłs-Graduação em Design, strictu senso, da Universidade Anhembi Morumbi (onde leciono desde 2006) de março a junho de 2022. Coincidiu com o retorno Ă s aulas presenciais depois de dois anos de aulas remotas. Havia uma intensa necessidade de comunicação, de troca de experiĂŞncias, de explicitação de afetividade, de envolver os processos de aprendizagem intelectuais com as vivĂŞncias de cada participante da disciplina. De inĂcio Ă©ramos apenas mulheres, mas a nĂłs se juntaram, como ouvintes, um designer e coordenador de escola privada e, quase no fim da disciplina um doutorando, professor de tecnologias contemporâneas. NĂŁo me pareceu que tiveram dificuldades em dialogar com nossa linha de reflexĂŁo que havia, sem planejamento anterior, se encaminhado para as reflexões feministas igualitaristas. No primeiro dia de aula receberam a proposta da disciplina que começava com a Centennial Exhibition na Philadelfia em 1876, o grande sucesso da presença de D.Pedro II registrada nos jornais da Ă©poca , inclusive no New York Times , assim como o sucesso da exposição pedagĂłgica sobre ensino de Design dos alunos de Walter Smith que tanto encantou o imperador e Rui Barbosa. Passamos depois a analisar o design nas Exposições Industriais de 1908 (Exposição Nacional, no Rio de Janeiro, comemorativa do centenário da abertura dos portos do Brasil Ă s nações amigas) com destaque para o pavilhĂŁo do Pará projetado por Theodoro Braga um dos pioneiros no ensino do Design no Brasil. Examinamos tambĂ©m a Exposição Internacional de 1922, comemorativa da independĂŞncia do paĂs comparando do ponto do decolonialismo com a excelente exposição de Arte e Cultura intitulada “Raio-que-o-parta: Ficções do Moderno no Brasil” apresentada naquele mĂŞs no SESC 24 de Maio SP sobre os modernismos, a qual foi um exemplo muito bem sucedido de modelo curatorial e de design de rompimento com o cubo branco europeu. Essa exposição, que posso designar de decolonial, foi analisada em diálogo com a Exposição “Era uma vez o Moderno [1910-1944]” do IEB/USP tambĂ©m visitada pelas/os alunas/os, formalmente alinhada aos cânones curatoriais europeus modernistas. Como era baseada nos arquivos de Mário de Andrade foi muito informativa e nos fez perceber o quanto ele era um intelectual Ă frente de seu tempo, o que foi potencializado pela arte/educadora Elly Ferrari do IEB, que orientou nossa visita e nos deu uma aula excelente.TambĂ©m no primeiro dia da aula foi entregue a proposta de trabalho final, a qual sugeria fazer uma entrevista publicável com um/uma designer que já tivesse comprovado que valorizava Educação ou fosse professor ou professora, mas nĂŁo da Anhembi, por razões Ă©ticas. É bom lembrar que há um preconceito grande em pensar a Educação nas Artes e no Design por parte de profissionais mesmo muito bem sucedidos. A educação Ă© vista pelas elites como mediocrização ou assistencialismo. Uma lista de designers culturalistas importantes na histĂłria contemporânea do Design no Brasil foi apresentada aos alunas/os. Discutiu-se o que cada estudante sabia acerca da produção daqueles/as designers. Na aula seguinte cada um/a escolheu seu entrevistado e foram discutidas as diferentes formas de entrevistas e principalmente como devemos nos preparar para entrevistar alguĂ©m de quem queremos saber mais informações, dados e especialmente ideias. Critica-se veementemente o entrevistador que nĂŁo conhece nada do entrevistado, faz perguntas Ăłbvias e irrelevantes. As/os alunos/as receberam orientação por escrito de perguntas que interessavam para nossa disciplina, acrescentaram possĂveis perguntas que interessavam para suas teses e atĂ© algumas fontes onde se informarem acerca da/o entrevistada/o. Uma das dicas foi ver o trabalho e ler todas as entrevistas, lives e cursos que a/o designer escolhida/o houvesse dado. A professora ficou responsável em dar o primeiro passo, apresentando por e-mail a/o aluna/o Ă quela pessoa escolhida para ser entrevistada. No mesmo e-mail tambĂ©m foram enviados aos entrevistados o programa do curso, assim como as orientações acima descritas que haviam sido dadas por escrito aos pĂłs-graduandos. Os/as entrevistados/as foram tratados/as como co-participantes da disciplina e assim podiam avaliar se concordavam em se tornarem cĂşmplices daquela experiĂŞncia. Apresentamos aqui duas entrevistas, uma com a designer Joice Leal e a outra com Rico Lins. Antes de serem submetidas para publicação, as entrevistas foram lidas, discutidas, corrigidas e aprovadas pelos/as entrevistados/as
Cyclophosphamide in Drosophila promotes genes and transposable elements differential expression and mitochondrial dysfunction
Cyclophosphamide (CPA) is an alkylating agent used for cancer chemotherapy, organ transplantation, and autoimmune disease treatment. Here, mRNA sequencing and high-resolution respirometry were performed to evaluate the alterations of Drosophila melanogaster gene expression fed with CPA under acute (0.1 mg/mL, for 24 h) and chronic (0.05 mg/mL, for 35 days) treatments. Differential expression analysis was performed using Cufflinks-Cuffdiff, DESeq2, and edgeR software. CPA affected genes are involved in several biological functions, including stress response and immune-related pathways, oxi-reduction and apoptotic processes, and cuticle and vitelline membrane formation. In particular, this is the first report of CPA-induced mitochondrial dysfunction caused by the downregulation of genes involved with mitochondria constituents. CPA treatment also changed the transcription pattern of transposable elements (TEs) from the gypsy and copia superfamilies. The results presented here provided evidence of CPA mitochondrial toxicity mechanisms and that CPA can modify TEs transcription in Drosophila flies
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