1,565 research outputs found
Impact of the metabolic program of germline cells on feeding behaviour
Animals control how much and what they eat to ensure an optimal nutrient balance for organismal function. Drosophila melanogaster shows specific nutrient appetites depending on its internal nutrient and mating state. We hypothesize that the Central Nervous System (CNS) is able to read the nutritional requirements of several organs and adapt feeding behavior to maintain tissue nutrient homeostasis. Oogenesis is a highly metabolically demanding process, strongly responding to nutrient availability and a large part of carbohydrates ingested by females are used for egg production. Females without germline show a strong reduction in sugar appetite even when carbohydrate-deprived, suggesting that indeed the CNS can sense the nutrient requirements of this organ and instruct the animal to behave accordingly. We hypothesize that carbohydrate metabolism in the germline might underlie this modulation of sugar appetite. To address this hypothesis, we took advantage of Drosophila melanogaster’s vast array of genetic and molecular tools, together with a high precision quantitative assay for fly feeding behaviour (flyPAD) and a full synthetic diet that allows precise nutrient manipulations of the diet. We show that dietary sugar is key for maintaining optimal egg production, since dietary sucrose deprivation reduces egg-laying by 37%. Furthermore, we show that egg production is highly dependent on the Pentose Phosphate Pathway (PPP) as we show that down-regulating the levels of enzymes in this pathway leads to a drastic reduction in egg-laying. Finally, we also show that the PPP in the germline modulates sugar appetite.
Our data supports a model where the germline cellular metabolic program is surveyed by the CNS to modulate the uptake of carbohydrates in order to achieve high fertility. It will be interesting to explore if pathologies in which cellular metabolic programs are altered, such as in certain tumors, also impinge on appetites in order to obtain the required nutrients for disease progression
Study of Innovative Building Integrated Photovoltaic (BIPV) Products and Solutions Based on Thin Film and c-Si Technologies
Telecommunications for the Needy: How needed are they?
Telecommunications, mobile and non-mobile, play a major role in our society, but their role as tools for escaping poverty remains a policy agenda still with room for progress both in Europe and around the World. Some groups in society, like the needy, have difficulties in accessing and using such technologies in ways that mirror the debates of the late 90s over the "digital divide". For some groups, like the needy, it would be more exact to address the concept of digital poverty rather than digital divide, because without access to telecommunications one might not have the same degree of opportunities to leave poverty or not to fall into poverty [34] [3] [4]. The goal of this paper is to scope the problem by departing from the Portuguese case study. Our research is empirical and highlights the telecommunication ownership and expenditures of the Portuguese population, and specially the most fragile segments within it. Such an effort is undertaken while not ignoring major issues of political economy of the contemporary globalizing networked society. Our main argument in this paper is that, if telecommunications are a needed tool for the lower income segments of the population, that is the needy, a debate around digital poverty associated to mobile telecommunications is needed in Europe too and to address such issues we need public policy commitments.needy, mobile telecommunications, digital poverty, digital divide, telecommunication policies
Cuidados alimentares e nutrição na demência: da prevenção aos cuidados paliativos
Trabalho Complementar apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de licenciada em Ciências da NutriçãoObjetivo: Efetuar uma revisão tradicional da literatura sobre o papel que a alimentação/nutrição tem, quer na prevenção quer na progressão da demência incluindo a fase final da vida.
Metodologia: Foi realizada pesquisa bibliográfica no PubMed e na B-On, entre fevereiro e julho de 2013, que abarcou todas as publicações relativas aos últimos 5 anos. Utilizaram-se, para isso, as seguintes palavras-chave “palliative care AND dementia” e “nutrition AND dementia”.
Resultados: As vitaminas dos complexos B e D, os antioxidantes e os ácidos gordos polinsaturados ómega-3 têm sido demonstrados como benéficos para a prevenção da demência. Uma vez que a maioria dos estudos efetuados até ao momento mostram que elevadas quantidades destes nutrientes estão associadas a um menor risco de desenvolver a doença. Este efeito benéfico é mais evidente na prevenção do que na terapia quando a doença já se encontra instalada.
No entanto, quando a demência está instalada e numa fase avançada poderão ser necessários cuidados paliativos. Estes cuidados são de extrema importância para estes doentes pois, à medida que a doença progride, tornam-se completamente dependentes em termos de auto-cuidados. Nesta fase final a alimentação/nutrição também assume um papel de destaque, focando-se na promoção da qualidade de vida e alívio do sofrimento.
Conclusões: As evidências existentes até ao momento são consistentes e encorajadoras a nível da prevenção, sendo contudo necessário a realização de mais estudos que comprovem o potencial efeito benéfico para a saúde pública. Objective: Make a traditional review of the literature about the role that diet/nutrition have, either in prevention or progression of dementia, including the final stage of life.
Methodology: Was performed a literature search on Pubmed and B-on from February to July of 2013, that included all publications for the past 5 years. We used to his the following keywords “palliative care AND dementia” and “nutrition AND dementia”.
Results: The complex of vitamins B and D, antioxidants and polyunsaturated fatty acids omega-3 have been shown to be beneficial for the prevention of dementia. Once most of the studies conducted so far show that high amounts of these nutrients are associated with a lower risk of developing the disease. This beneficial effect is more evident on prevention rather than therapy when the disease is already installed.
However, when dementia is installed and an advanced stage, palliative care may be needed. Such care is extremely important for these patients, because with the progress of the disease, they become completely dependent in terms of self-care.
In this terminal stage diet/nutrition also plays an important role, focusing on the promotion of the quality of life and the relief of suffering.
Conclusions: The existing evidences to data are consistent and encouraging in prevention, but further studies are need to prove the potential beneficial effect on public health
Otimização de crescimento e fotofisiologia de duas estirpes de Arthrospira platensis
Arthrospira platensis is a spiral and filamentous cyanobacteria, popularly known as Spirulina, naturally present in highly alkaline lakes. With high nutritional value, it is applied in supplements for human and animal food, being valued for its high protein content (about 60%), antioxidant and anti-inflammatory properties and the presence of pigments such as phycocyanin and β-carotenes, as well as vitamin B12 and omega 3. Due to the growing interest and popularization by the wellness industry, it is industrially produced on an ever-increasing scale. The testing of the cultivation conditions used by the industry, as well as their improvement, with practical applicability is, therefore, of great relevance. In the present study, the evolution of growth and photophysiology of two strains of A. platensis (Chad and UTEX LB2340) is tested with different salinities and temperatures, with the main goal of improving its growth conditions. Based on standard growth conditions (“Spirulina medium”, 35°C, salinity 15 and high light intensity), one of the strains (Chad) was subjected to a test of salinities of 15 (control), 25 and 35, as well as industrial culture medium. Both strains were subjected to an acute temperature test, in a range of 5 to 65°C, in order to assess their photosynthetic response. Growth curves were determined through optical density and assessment of chlorophyll ɑ content, as well as assessment of photophysiological responses using modeled pulse fluorometry. The results demonstrate that the species under study prefer laboratory growth conditions, however, there is potential to produce in salt water, since it shows photosynthetic efficiency when subjected to salinities of 25 and 35. The industrial environment proved to be the least promising in terms of photophysiological response and amount of pigment. Regarding the temperature test, both strains of A. platensis showed a clear preference for values above 35°C, established as optimal by the literature, reaching the maximum photosynthetic efficiency (determined by the parameter “relative electron transport rate”), at 50 and 55°C, respectively for strain UTEX2340 and “Chad”. A test based on the PCR methodology was also carried out to identify the two strains, the results of which are preliminary.Arthrospira platensis é uma cianobactéria helicoidal e filamentosa, popularmente conhecida como Spirulina, naturalmente presente em lagos altamente alcalinos. Com alto valor nutricional, é aplicada em suplementos para alimentação humana e animal, sendo valorizada pelo elevado teor em proteína (cerca de 60%), propriedades antioxidantes e anti-inflamatórias e presença de pigmentos como ficocianina e β-carotenos, bem como vitamina B12 e ómega-3. Devido ao crescente interesse e popularização pela indústria do bem-estar, é industrialmente produzida numa escala cada vez maior. A testagem das condições de cultivo utilizadas pela indústria, bem como o seu aprimoramento, com aplicabilidade prática é, portanto, de grande relevância. No presente estudo, a evolução do crescimento e fotofisiologia de duas estirpes de A. platensis (Chad e UTEX LB2340) é testada com diferentes salinidades e temperaturas, tendo como objetivo principal o melhoramento das condições de cultivo. Tendo como base as condições de crescimento padrão (“Spirulina medium”, 35°C, salinidade 15 e elevada intensidade luminosa), uma das estirpes (Chad) foi submetida a um teste de salinidades de 15 (controlo), 25 e 35, bem como a meio de cultura industrial. Ambas as estirpes foram sujeitas a um teste agudo de temperatura, num espetro de 5 a 65°C, de forma a avaliar a sua resposta fotossintética. Foram determinadas curvas de crescimento através de densidade ótica e avaliação do teor de clorofila, bem como avaliação de respostas fotofisiológicas recorrendo a fluorometria de pulso modelado. Os resultados demonstram que a espécie em estudo prefere meio laboratorial, no entanto, demonstra potencial para ser produzida em água salgada, uma vez que evidencia eficiência fotossintética quando sujeita a salinidades de 25 e 35. O meio industrial mostrou ser o menos promissor em termos de resposta fotofisiológica e quantidade de pigmento. Em relação ao teste de temperatura, ambas as estirpes de A. platensis, demonstraram uma clara preferência por valores acima dos 35°C, estabelecidos como ótimos pela literatura, atingindo o máximo de eficácia fotossintética (determinada pelo parâmetro “taxa relativa de transporte de eletrões”), aos 50 e 55°C, respetivamente para a estirpe UTEX2340 e “Chad”. Foi ainda realizado um teste baseado na metodologia de PCR, para identificação das duas estirpes, cujos resultados são preliminares.Mestrado em Biologia Marinha Aplicad
Anti-neoplastic effect of MLo-1302 in Testicular Germ Cell Tumors: comparation with classical differentiating and demethylating agents, ATRA and DAC
Maybelline New York, how to grow in Portugal?
A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and EconomicsThis document consists of a market research on the Portuguese make-up market, and more
specifically on the brand Maybelline New York. The purpose of this project is to understand the
consumers’ feelings / opinions regarding this brand, in order to suggest possible strategies for
Maybelline to grow in Portugal. The marketing research for this work started with an exploratory
research (15 in-depth interviews), followed by a quantitative research based on a pre-arranged
questionnaire (90 respondents). The main findings were that Maybelline NY is one of the make-up
brands with strongest awareness. However, the majority of the respondents do not recognize
themselves in this brand, it is associated with “exaggeration”, and this leads the interviewees to think
that it is not adequate for Portuguese women. Finally, besides all make-up-related products, the
respondents believe that Maybelline should extend to treatment products, especially face treatment
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