569 research outputs found

    The eurozone target-system from the perspective of Portugal

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    Payment systems make a significant contribution to the flow of transactions and financial stability. In this paper, we start by applying the principles of the gravity model to explain the TARGET flows of banking transactions between Portugal and other eurozone countries. The main explanatory variables tested are a composite indicator of economic and financial activities, distance, membership of the Eurozone (EZ), and country risk measured by treasury bond yields. The results indicate that Portugal has a high level of integration in the European banking market as distance is not statistically significant, and that the membership of the EZ facilitates the financing of the economy. The economic size of the partner country becomes non-significant after controlling for country fixed effects. The increase in the Portuguese country risk during the European sovereign debt crisis led to a marked decline in external financing, indicating that this is an important channel of transmission of crises

    Jacobi-Nijenhuis algebroids and their modular classes

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    Jacobi-Nijenhuis algebroids are defined as a natural generalization of Poisson-Nijenhuis algebroids, in the case where there exists a Nijenhuis operator on a Jacobi algebroid which is compatible with it. We study modular classes of Jacobi and Jacobi-Nijenhuis algebroids

    Conjunctival vaccination against Brucella ovis in mice with mannosylated nanoparticles

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    The use of sub-unit vaccines can solve some drawbacks associated with traditional attenuated or inactivated ones. However, in order to improve their immunogenicity, these vaccines needs to be associated to an appropriate adjuvant which, adequately selected, may also offer an alternative pathway for administration. The aim of this work was to evaluate the protection offered by the hot saline complex extracted from Brucella ovis (HS) encapsulated in mannosylated nanoparticles (MAN-NP-HS) when instilled conjunctivally in mice. Nanoparticles displayed a size of 300 nm and the antigen loading was close to 30 μg per mg nanoparticle. Importantly, encapsulated HS maintained its protein profile, structural integrity and antigenicity during and after the preparative process of nanoparticles. The ocular immunization was performed on BALB/c mice. Eight weeks after vaccination animals were challenged with B. ovis, and 3 weeks later, were slaughtered for bacteriological examinations. Animals immunized with MAN-NP-HS displayed a 3-log reduction in spleen CFU compared with unvaccinated animals. This degree of protection was significantly higher than that observed for the commercial vaccine (Rev1) subcutaneously administered. Interestingly, the mucosal IgA response induced by MAN-NP-HS was found to be much more intense than that offered by Rev1 and prolonged in time. Furthermore, the elicited IL-2, IL-4 and γ-IFN levels showed good correlation with the degree of protection. On the other hand, biodistribution studies in animals were performed with nanoparticles labelled with either 99mtechnetium or rhodamine B isothiocyanate. The biodistribution revealed that, after instillation, MAN-NP-HS moved from the palpebral area to the nasal region and, the gastrointestinal tract. This profile of distribution was different to that observed for free 99mTcO4− colloids, which remained for at least 24 h in the site of administration. In summary, mannosylated nanoparticles appear to be a safe and suitable adjuvant for conjunctival vaccination

    Iodination of phenols in water using easy to handle amine-iodine complexes

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    The reaction between iodo and N-methyl-piperazine or thiomorpholine in water, in the presence of KI, led to the formation of stable and easy to handle amine-iodine complexes, as the complex morpholine-iodo previously reported in the literature. However, the complex obtained using N,N-tetrametylethylenediamine proved less stable, while no complex was formed when piperidine was used as base. These results show that the presence of a second heteroatom in the structure of amines is of fundamental importance for the formation and stability of these complexes. In this work we describe, for the first time, the use of complexes morpholine-iodo, N-methyl-piperazine-iodo and thiomorpholine-iodo as iodinating reagents of several substituted phenols, leading to iodinated products in good to excellent yields

    Exploratory Insights into Consumption and Commercialization of Organic Products during COVID-19 Pandemic

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    A questionnaire survey was designed to investigate the consumption habits and commercialization of organic products in Portugal, under COVID-19 restrictions. Results showed that most participants are familiar with organic farming and have consumed organic foods, mostly fruits and vegetables, and less meat or dairy products. Reasons to consume organic products include environmental concern, helping local producers and eliminating harmful substances such as pesticides from diet. Although the majority have consumed organic foods, there is still a small percentage of consumers who do not, and for those it is because of the high prices of organic compared to conventional food.info:eu-repo/semantics/publishedVersio

    Methylphenidate modifies reward cue responses in adults with ADHD: An fMRI study

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    Attention deficit hyperactivity disorder (ADHD) has been associated with neural hyposensitivity to reward-predicting cues. Methylphenidate is widely used in the management of the disorder\u27s symptoms, but its effects on reward sensitivity in ADHD are unknown. The current study used fMRI to measure striatal responses to reward-predicting cues in adults with ADHD on and off methylphenidate and a control group, during a classical conditioning task. Responses to cued reward were also explored. Larger differences in the ventral striatum activation to reward cues versus non-reward cues were observed when the ADHD participants were on methylphenidate compared to placebo. In response to cued-reward outcome, an exploratory analysis showed methylphenidate reduced the BOLD time-series correlation between the dorsal striatum and dorsal medial prefrontal cortex. Methylphenidate\u27s therapeutic effects may be mediated by altering reward processing in individuals with ADHD

    Radiomarcaje y estudios de biodistribución de nanopartículas poliméricas como adyuvantes para la vacunación oftálmica frente a la brucelosis

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    Objetivos: Optimizar el radiomarcaje con 99mTc de nanopartículas de Gantrez® manosiladas y cargadas con el antígeno de Brucella Ovis (Man-NP-HS) y llevar a cabo estudios de biodistribución en ratón tras la administración de las nanopartículas por vía ocular. Metodología: Las Man-NP-HS se obtuvieron por el método de desplazamiento de disolvente. Se purificaron, liofilizaron y caracterizaron. A continuación, se marcaron con 74 MBq de 99mTcO4 - previamente reducido con una disolución ácida de cloruro de estaño, trabajando en ausencia de oxígeno y con un pH final de 4. El rendimiento del marcaje se evaluó mediante TLC. Los estudios de biodistribución se llevaron a cabo en ratones tras la administración oftálmica de la formulación y de un control de 99mTcO4 - libre. Para ello, se sacrificaron los animales a las 2 y a las 24 horas tras la administración ocular y se contaron los órganos en un contador gamma. Resultados: Se obtuvo un rendimiento de marcaje superior al 90%. Los estudios de biodistribución de 99mTc-Man-NP-HS permitieron detectar la actividad concentrada en mucosa nasal y ocular y tracto gastrointestinal tanto a las 2 como a las 24 horas, frente a la biodistribución de 99mTcO4 - libre que permaneció concentrado en la piel alrededor del ojo y en tracto gastrointestinal. Conclusión: Los estudios de biodistribución de 99mTc-Man-NP-HS tras administración oftálmica han permitido demostrar su biodistribución en mucosas y tracto gastrointestinal, característica indispensable como sistema de liberación de antígenos a través de mucosa ocular. Esto, junto con su elevada respuesta inmune, efectiva protección y no virulencia, convierte a estas nanopartículas en una vacuna ideal anti Brucelosis

    Valorization of sugarcane by-products through synthesis of biogenic amorphous silica microspheres for sustainable cosmetics

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    Ashes from sugarcane by-product incineration were used to synthesize silica powders through alkaline hot extraction, followed by ethanol/acid precipitation or the sol–gel method. Both production methods allowed amorphous spherical silica microparticles with sizes ranging from 1–15 μm and 97% purity to be obtained. Water absorption ranged from 135–155 mL/100 g and 150–250 mL/100 g for precipitated silica and silica gel, respectively, while oil absorption ranged from 305 to 390 and from 250 to 350 mL/100 g. The precipitation with ethanol allowed the recovery of 178 g silica/kg ash, with a lab process cost of EUR 28.95/kg, while the sol-gel process showed a yield of 198 g silica/kg ash with a cost of EUR 10.89/kg. The experimental data suggest that ash from sugarcane by-products is a promising source to be converted into a competitive value-added product, minimizing the environmental impact of disposal problems.info:eu-repo/semantics/publishedVersio

    Efeito do teor de água e tamanho de partícula na decomposição térmica de pastas de cimento moídas

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    Um método alternativo para produção de concretos ecoeficientes seria a substituição parcial de cimento Portland por resíduos de pastas e argamassas submetidas a um tratamento termomecânico. Neste contexto, este estudo avalia a influência da relação água/cimento (a/c) e do tamanho médio das partículas na decomposição térmica do cimento hidratado. Pastas de cimento com três relações a/c (0,40, 0,50 e 0,60) e curadas por 28 dias foram moídas para obtenção de granulometrias com tamanho médio de 0,60 mm e 0,15 mm. A decomposição térmica das pastas foi analisada por termogravimetria (TGA), difração de raios X (DRX) e espectroscopia no infravermelho por Transformada de Fourier (FTIR). A análise de TGA indica que o teor de água quimicamente combinada é favorecido pelo aumento da relação a/c entre 0,40 e 0,50, mas é constante para a/c de 0,50 e 0,60. A redução do tamanho médio quase não interfere nas curvas de TGA. De acordo com as análises por DRX e TGA, a maior parte dos hidratos se decompõe até 500-550°C, enquanto que silicatos de cálcio e aluminatos de cálcio similares às fases anidras do cimento Portland foram detectados na pasta aquecida a 750°C. Assim, temperaturas mais altas seriam necessárias para a completa recuperação do cimento anidro em pastas hidratadas.  Palavras-chave: Pasta de cimento Portland, decomposição térmica, relação água/cimento, tamanho de partículas, análises térmicas
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