Studies on glutamate synthase from the roots of maize. Effects of nicotinamide-adenine dinucleotides and inorganic salts on its activity

A actividade da glutamato sintase de raízes de milho foi medida na presença de diferentes concentrações de NAD(P)H. A glutamato sintase dependente do NADH (EC 1.4.1.14) não exibiu actividade quando se utilizou o NADPH como única fonte de equivalentes redutores, mas a presença desta coenzima no meio da reacção (utilizando NADH como agente redutor) inibiu a sua actividade. Também foram observados efeitos inibitórios na presença de concentrações elevadas de NADH. A representação gráfica de va em função da concentração de NADH mostrou um aumento de actividade enzimática até 100 /iM, decrescendo posteriormente de maneira gradual até se tornar indetectável para concentrações de NADH próximas de 600 /íM. Foram examinados os efeitos de alguns catiões na actividade da glutamato sintase, tendo-se observado um aumento de actividade na presença de cálcio. A estimulação máxima da actividade (até 126%) foi obtida para concentrações de cálcio entre 0,25 e 2,5 mM, o que dependia das condições de ensaio. Foram observados idênticos efeitos estimulatórios com o estrôncioinfo:eu-repo/semantics/publishedVersio

Quality and durability properties and life-cycle assessment of high volume biomass fly ash mortar

The effect of using biomass fly ash (BFA) on the quality, durability and sustainability of mortars was studied. Using high amounts of BFA does not lead to a production of mortars with better performance than a plain cement mortar. However, when BFA is used in small amounts mixed with coal fly ash, mortars with similar compressive strength, to that of a cement mortar, but with less carbonation and with better environmental performance are obtained. Using BFA in the concrete industry can lead to a minimisationof issues related to the high volume fly ash concrete.The authors wish to thank the Portuguese Foundation for Science and Technology (FCT) and the Eco-Construction and Rehabilitation Doctoral Program for supporting the PhD scholarship (reference PD/BD/52661/2014). This work was also financed by FEDER funds through the Competitivity Factors Operational Programme – COMPETE and by national funds through FCT – Foundation for Science and Technology within the scope of the project POCI-01- 0145-FEDER- 007633 and through the Regional Operational Programme CENTRO2020 within the scope of the project CENTRO-01- 0145-FEDER- 000006.info:eu-repo/semantics/publishedVersio

Light with tunable non-Markovian phase imprint

We introduce a simple and flexible method to generate spatially non-Markovian light with tunable coherence properties in one and two dimensions. The unusual behavior of this light is demonstrated experimentally by probing the far field and recording its diffraction pattern after a double slit: In both cases we observe instead of a central intensity maximum a line or cross shaped dark region, whose width and profile depend on the non-Markovian coherence properties. Since these properties can be controlled and easily reproduced in experiment, the presented approach lends itself to serve as a testbed to gain a deeper understanding of non-Markovian processes

Comparative environmental life-cycle analysis of concretes using biomass and coal fly ashes as partial cement replacement material

Nowadays, the concrete production sector is challenged by attempts to minimize the usage of raw materials and energy consumption, as well as by environmental concerns. Therefore, it is necessary to choose better options, e.g. new technologies or materials with improved life-cycle performance. One solution for using resources in an efficient manner is to close the materials' loop through the recycling of materials that result either from the end-of-life of products or from being the by-product of an industrial process. It is well known that the production of Portland cement, one of the materials most used in the construction sector, has a significant contribution to the environmental impacts, mainly related with carbon dioxide emission. Therefore, the study and utilization of by-products or wastes usable as cement replacement in concrete can supply more sustainable options, provided that these type of concrete produced has same durability and equivalent quality properties as standard concrete. This work studied the environmental benefits of incorporating different percentages of two types of fly ashes that can be used in concrete as cement replacement. These ashes are waste products of power and heat production sectors using coal or biomass as fuels. The results showed that both ashes provide a benefit for the concrete production both in terms of environmental impact minimization and a better environmental performance through an increase in cement replacement. It is possible to verify that the incorporation of fly ashes is a sustainable option for cement substitution and a possible path to improve the environmental performance of the concrete industry.The authors wish to thank to FCT (Fundação para a Ciência e Tecnologia – Portugal) and to the Doctoral Program Eco-Construction and Rehabilitation (EcoCoRe) for supporting the PhD scholarship (with the grant-number PD/BD/52661/2014)

The influence of the pedagogical model on psychological variables in 1st year students from ESTSP-IPP

Introdução – A adaptação ao ensino superior reveste-se de experiências académicas que podem constituir fonte de stress para os estudantes. A implementação de novos modelos pedagógicos, no âmbito do processo de Bolonha, introduz novas variáveis cujo impacto, designadamente em termos de saúde, importa conhecer. Este estudo tem como objetivo analisar as associações entre modelo pedagógico (Problem Based Learning – PBL vs. modelos próximos do tradicional) e variáveis psicológicas (coping, desregulação emocional, sintomas psicossomáticos, perceção de stress e afeto). Metodologia – O estudo tem um design transversal. Foram usados os seguintes questionários online: Brief-COPE, Escala de Dificuldades de Regulação Emocional, Questionário de Manifestações Físicas de Mal-Estar, Escala de Stress Percebido e Escala de Afeto Positivo e Negativo. A amostra é constituída por 183 estudantes do primeiro ano (84% do género feminino) de cursos da Escola Superior de Tecnologia da Saúde do Porto – Instituto Politécnico do Porto (ESTSP-IPP). Resultados – Foram encontradas correlações significativas entre as variáveis demográficas e psicológicas. Considerando diferentes modelos pedagógicos, foram encontradas diferenças significativas nas variáveis psicológicas. Os principais preditores de stress na amostra foram: ser mulher, frequentar uma licenciatura no modelo PBL, ter maiores índices de desregulação emocional, apresentar mais sintomas psicossomáticos, menos afeto positivo e mais afeto negativo. Conclusão – As diferenças encontradas entre modelos pedagógicos são discutidas, possibilitando a reflexão sobre as implicações práticas e sugestões para futuras investigações.Introduction – Adapting to Higher Education is filled with academic experiences that might be stressful for students. The new pedagogical models brought about by the Bologna process put into play new variables that are important to look at, namely in terms of health. This research aims to analyze associations between the pedagogical model (Problem Based Learning vs more traditional approaches) and psychological variables (coping, emotional deregulations, psychosomatic symptoms, perceived stress and affect). Method – This study has a cross-sectional design. The following online questionnaires were used: Brief-COPE, Difficulties in Emotion Regulation Scale, Perceived Stress Scale, Manifestations of Physical Discomfort Questionnaire, and Positive and Negative Affect Schedule. The sample consisted in 183 first-year students (84% female) from School of Allied Health Sciences – Polytechnic Institute of Porto. Results – Significant correlations between demographic and psychological variables were found. Considering different pedagogical models, significant differences in psychological variables were found. The main predictors of stress in the sample were: being female, inclusion in the PBL model, higher indexes of emotional deregulation, more psychosomatic symptoms, lower positive affect and higher negative affect. Conclusion – Differences between pedagogical models are discussed, while reflecting on practical implications and suggestions for future research

Purification and Preliminary Crystallographic Analysis of a New Lys49-PLA2 from B. Jararacussu

BjVIII is a new myotoxic Lys49-PLA2 isolated from Bothrops jararacussu venom that exhibits atypical effects on human platelet aggregation. To better understand the mode of action of BjVIII, crystallographic studies were initiated. Two crystal forms were obtained, both containing two molecules in the asymmetric unit (ASU). Synchrotron radiation diffraction data were collected to 2.0 Å resolution and 1.9 Å resolution for crystals belonging to the space group P212121 (a = 48.4 Å, b = 65.3 Å, c = 84.3 Å) and space group P3121 (a = b = 55.7 Å, c = 127.9 Å), respectively. Refinement is currently in progress and the refined structures are expected to shed light on the unusual platelet aggregation activity observed for BjVIII

Enzymatic approach for the extraction of bioactive fractions from red, green and brown seaweeds

Although several enzymatic approaches have been applied with this intent, the sequential use of enzymes covering both cellulolytic and proteolytic activity has never been performed in seaweeds. Sequential use of these enzymes improved the overall extraction yield by up to 160%, 30% and 80% in the different seaweeds when compared to the control condition (water extraction), use of a carbohydrases’ cocktail alone and use of proteases alone, respectively. Regarding the proximate composition of extracts, it proved to be an efficient approach for the solubilization of carbohydrates (up to 28% in G. vermiculophylla, 66% in P. dioica, 77% in U. rigida and 35% in F. vesiculosus) and protein (up to 55% in G. vermiculophylla, 47% in P. dioica, 52% in U. rigida and 42% in F. vesiculosus). For all biomasses, the combination of enzymes induced a significant increase in antioxidant activity, not only by the increase of phenolic compounds but also by the hydrolysis of protein to peptides. Moreover, extracts from red seaweeds displayed prebiotic activity which can be ascribed to their increased content in oligosaccharides and protein/peptides. Overall, the sequential use of enzymes with different activities demonstrated to be an efficient approach for extracting functional fractions to be used as functional ingredients to improve the nutritional value (e.g. in proteins) and/or to include antioxidant and prebiotic features in the food product.info:eu-repo/semantics/publishedVersio

Desempeño de cabritos recibiendo dietas liquidas con diferentes niveles de grasa durante la etapa de amamantamiento

The aim of the study were to evaluate different levels of inclusion of goat milk fat in the diet of kids during the first 37 days and study its effect on performance, through the intake and nutrient digestibility. Sixty male kids of Saanen and Alpine races were used. The treatments consisted in five levels (2.42; 3.44; 4.43; 6.56; 2.42 and 8.21%) of fat in the diet, and a complete randomized design with 12 repetitions was used. After seventh day of life each animal fed 1.5 liters of milk divided into two portions (08:00 - 15: 00 hours); individual dry matter intake (DMI) was obtained by the difference between the quantity and orts. Digestibility of nutrients was determined by the total collection of feces method. Samples were subsequently subjected to chemical analysis. The intake of dry matter and nutrients evaluated was influenced (p<0.001) for the content of fat in the diet, presenting quadratic effect. Similarly, the coefficient of digestibility of ether extract (CDEE) and non-fibrous carbohydrates (CDCNF) were affected (p = 0.015, p=0.001, respectively), showing linear and quadratic effect. Increasing energy concentration of the diet to the level of inclusion of 6.56% milk fat, increases the DMI, CDCNF and CDEE, however, this increase does not cause improvements in weight gain during this phase, not justifying the addition of milk cream.Los objetivos del estudio fueron evaluar diferentes niveles de inclusión de grasa de leche de cabra en la alimentación de cabritos durante la fase de amamantamiento (37 días de vida) y estudiar su efecto en el desempeño, a través del consumo y digestibilidad de los nutrientes. Se utilizaron 60 cabritos machos de las razas Saanen y Alpina, con inclusión de cinco niveles de grasa en la dieta (2,42; 3,44; 4,43; 6,56; y 8,21 %), utilizando un diseño completamente al azar con 12 repeticiones. A partir del séptimo día de vida cada unidad experimental recibió 1,5 L/leche/día dividida en dos raciones 08:00 -15:00 horas; el consumo individual de materia seca (CMS) fue obtenido por la diferencia entre la cantidad ofrecida y las sobras. Se determinó la digestibilidad de los nutrientes a través del método directo por colecta total de heces. Las muestras fueron posteriormente sometidas a análisis químico. El CMS fue influenciado (p<0,001) por el contenido de grasa en la dieta, presentando comportamiento cuadrático; efecto observado en los demás nutrientes. Igualmente, el coeficiente de digestibilidad del extracto etéreo (CDEE) y de los carbohidratos no fibrosos (CDCNF) se vieron afectados (p=0,015; p<0,001 respectivamente), observándose comportamiento linear y cuadrático respectivamente. Aumentar la concentración energética de la dieta hasta el nivel 6,56 % de inclusion de grasa lactea, aumenta el CMS, CDCNF y CDEE, sin embargo, este incremento no causa mejoras en la ganancia de peso durante esta fase, no justificando la adición de crema a la leche

Early psychiatric morbidity in a Brazilian sample of acute ischemic stroke patients

OBJECTIVE: Stroke is a major public health problem worldwide, and its neuropsychiatric sequelae are frequent and disabling. Furthermore, there is evidence that these sequelae impair recovery. Brazil has the highest stroke rates in Latin America, but data on the frequency of neuropsychiatric disorders in these patients are scarce. This study aimed to identify mental disorders among in-hospital patients with acute ischemic stroke. METHODS: The Mini International Neuropsychiatric Interview-Plus (MINI-Plus) was applied to 60 patients during the first week of hospitalization. RESULTS: Psychiatric disorders were diagnosed in 55% of the patients. A wide range of neuropsychiatric disorders have been identified, mainly mood and anxiety disorders. Specifically, we identified major depression (26.7%), alcohol abuse or dependence (11.7%), specific phobia (8.3%), generalized anxiety disorder (6.7%), psychosis (5.0%), social phobia (3.3%), adjustment disorder (3.3%) and panic disorder (1.7%). CONCLUSION: Psychiatric comorbidity should be evaluated as part of the rehabilitation of stroke patients and should be carefully examined by physicians