Avelã: composição química e efeitos benéficos associados ao seu consumo

Among the different nuts grown worldwide, hazelnut (Corylus avellana L.) is considered one of the most popular and consumed. Hazelnut is mainly used by the food industry in chocolates, cakes and desserts, with only a small part of the world’s produc"on being consumed as table hazelnut. Hazelnut is considered to be a highly nutri"ous food, providing macronutrients (fat, protein and carbohydrates), micronutrients (vitamins and minerals) and several bioac"ve phytochemicals, including phenolic acids, flavonoids, tannins and phytosterols, among others. Despite presen"ng a high content in fat, hazelnut lipids mainly include monounsaturated fa$y acids (MUFA), which have been associated with beneficial health effects, par"cularly regarding the cardiovascular system. Moreover, different interes"ng proper"es, such as an"oxidant, an"-inflammatory, an"-prolifera"ve and hipocholesterolemic ac"vi"es have been ascribed to several micronutrients and phytochemicals present in hazelnuts. To date, some studies have shown that the consump"on of hazelnuts can have a beneficial effect on health, namely by reducing the risk of cardiovascular diseases. Therefore, its inclusion has been recommended as part of a healthy-diet.Os autores agradecem o financiamento da Fundação para a Ciência e a Tecnologia (FCT) através do projeto UID/ QUI/50006/2013 - POCI/01/0145/FEDER/007265 com apoio financeiro da FCT/MEC através de fundos nacionais e cofinanciamento FEDER.info:eu-repo/semantics/publishedVersio

Temperature dependent thermal conductivity of magnetocaloric materials: impact assessment on the performance of active magnetic regenerative refrigerators

Due to the dynamic nature of the active magnetic regenerative mechanism in magnetocaloric refrigeration, the thermal conductivity of the refrigerant is a critical parameter. Experimental studies have shown how the thermal conductivity of high-performance magnetic refrigerants can drastically change around their Curie temperatures (TC). However, this fact has been largely ignored in the numerical simulation of devices, raising the need to assess the impact of this approximation, particularly when the simulations are aimed at optimizing or dimensioning a particular device geometry. In this paper we show how, by employing a unidimensional numerical model of a magnetic refrigerator with parallel plates, two different temperature dependent thermal conductivity scenarios of the refrigerant affect the resulting temperature span and cooling power. By considering a gadolinium-like material as the refrigerant with thermal conductivities varying 50% near its TC, a change of the resulting device temperature span of  ∼15% is reached. The cooling power is also affected, changing also  ∼15% when the considered systems are at half their respective maximum temperature span. Our results are also discussed in terms of other geometries where the impact of these effects can be even larger, namely in cases where the axial thermal conduction in the AMR element is not negligible, or the time-scale of longitudinal thermal processes has a larger impact on the optimum operating frequency.publishe

Avaliação da autenticidade de Alheiras de caça por identificação específica de espécies

A produção de diferentes enchidos tradicionais é uma práti-ca enraizada em várias regiões do país, em particular no Nordeste Transmontano onde é produzido um produto mui-to apreciados por diversos consumidores, nomeadamente a alheira. A alheira é um produto cárneo tradicional, fumado e fermentado, cuja origem remonta ao final do século XV e se relaciona com a presença de comunidades Judaicas nesta região. Naquela data, sendo frequente o consumo de enchi-dos pela população Cristã e sendo o porco uma espécie não consumida pelos Judeus, para evitar serem facilmente iden-tificados pela Inquisição pelos seus diferentes hábitos ali-mentares, estes começaram a produzir um enchido com forma similar à da cozinha Cristã, mas usando carne de aves em vez de porco. A receita foi, eventualmente, passando através de gerações e tornou-se popular também entre os Cristãos, sendo atualmente produzida com base numa mis-tura de carne e gordura de porco, carne de aves, pão de trigo, azeite, alho, sal e especiarias [1]. Dado o seu sucesso, nos últimos anos, têm surgido novas versões deste tipo de enchido, entra as quais se destacam as alheiras de caça. Estas distinguem-se das suas congéneres tradicionais pelo facto de incluírem na sua composição carne de caça, a qual pode ser adicionada total ou parcialmente em relação à car-ne utilizada na sua confeção.info:eu-repo/semantics/publishedVersio

A neural network based fall detector

In this project we present an intelligent fall detector system based on a 3-axis accelerometer and a neural network model that allows recognizing severaI possible motion situations and performing an emergency call only when a fall situation occurs, with low false negatives rate and low false positives rate. The system is based on a two module platform. The first one is a Mobile station (MS) and should be carried always by the person. An accelerometer is implemented in this module and its information is transferred via a radio-frequency channel (RF) to the Base station (BS). The BS is fixed and is connected to a GSM (Global system for Mobile communication) module. A neural network model was built in to the BS and is able to identify falls from other possible motion situations, based on the received information. According to the neural network response the system sends a SMs (short Message service) to a destination number requesting for assistance

A neural network based fall detector

In this project we present an intelligent fall detector system based on a 3-axis accelerometer and a neural network model that allows recognizing several possible motion situations and performing an emergency call only when a fall situation occurs, with low false negatives rate and low false positives rate. The system is based on a two module platform. The first one is a Mobile Station (MS) and should be carried always by the person. An accelerometer is implemented in this module and its information is transferred via a radio-frequency channel (RF) to the Base Station (BS). The BS is fixed and is connected to a GSM (Global System for Mobile communication) module. A neural network model was built into the BS and is able to identify falls from other possible motion situations, based on the received information. According to the neural network response the system sends a SMS (Short Message Service) to a destination number requesting for assistance

Development of structural layers PVC incorporating phase change materials for thermal energy storage

The use of poly(vinyl chloride) (PVC) structural layers incorporating phase change materials (PCM) for latent heat thermal energy storage (LHTES) has become more attractive in the recent years compared to other supporting materials. In this study, PVC layers with different types of PCM were prepared using blending and compression moulding methods. Two types of synthesized PCM, one based on paraffin and calcium carbonate (PCM@CaCO3) and the other on paraffin, silica and graphene oxide (PCM@SiGO) have been developed to enhance the thermal conductivity of the PVC matrix and thus achieve a more effective charging and discharging process. PVC layers prepared using a commercial PCM (PCM@BASF) were also prepared for comparison. SEM images and DSC results reveal homogeneous distribution of the PCM in PVC layers and that most PCM particles are undamaged. The shell material (in the case of PCM@BASF) and the shape stability (in the case of synthesized PCM@CaCO3 and PCM@SiGO) prevent leakage of molten paraffin during the PVC layer production. The thermal conductivity profile of the PVC layer without PCM have a decreasing tendency with the temperature increase when determined using different measurement approaches, the transient plane heat source method (HotDisk Analyser, TPS 2500 S) and thermal flux meter method (steady-state method). However, for PVC layers with PCM the thermal conductivity profile shows a different behaviour when the mean surface temperature of the specimen is below the phase change transition temperature range (increasing tendency). During phase change transition (18–26 °C), the thermal conductivity presents two distinct tendencies. Firstly, the thermal conductivity reveals a decreasing tendency as the mean temperature of the specimen rises and afterwards an increasing tendency. Secondly, when the mean surface temperature is above the phase change transition temperature range, the thermal conductivity profile shows a decreasing tendency, independent of the PCM. The mechanical properties of PVC layers were also assessed and the results obtained revealed that the incorporation of PCM into the PVC matrix reduces the mechanical performance of the composites, however for LHETS applications not subjected to high tensile stress levels (over 1 kPa), this is not a significant drawback.publishe

Avaliação nutricional e composição em ácidos gordos de 6 variedades de nozes, sementes de Juglans regia L., cultivadas em Trás-os-Montes

A dieta mediterrânea, considerada saudável e uma das melhores no que concerne à prevenção das doenças cardiovasculares inclui, como componentes importantes, os frutos secos. No entanto, e talvez devido ao facto deste tipo de alimentos ser rico em lípidos, assistiu-se a um declínio do seu consumo. Actualmente, associa-se o consumo de frutos secos à ingestão de ingredientes com propriedades funcionais. Quando comparadas com a maioria dos outros frutos secos, que contam principalmente ácidos gordos monoinsaturados, as nozes distinguem-se pelos teores elevados em ácidos gordos polinsaturados (omega-3 e omega-6)

The Complex Topology of Chemical Plants

We show that flowsheets of oil refineries can be associated to complex network topologies that are scale-free, display small-world effect and possess hierarchical organization. The emergence of these properties from such man-made networks is explained as a consequence of the currently used principles for process design, which include heuristics as well as algorithmic techniques. We expect these results to be valid for chemical plants of different types and capacities.Comment: 7 pages, 5 figures and 1 tabl

Classification PDO olive oils on the basis of their sterol composition by multivariate analysis

The sterol compositions (GLC/FID/capillary column) of monovarietal olive oils (51 samples) from the most important cultivars of northeastern Portugal (Cvs. Cobranc¸osa, Madural and Verdeal Transmontana) and 27 commercial samples of olive oils with protected denomination of origin (PDO) from the same region and cultivars were evaluated. Δ-sitosterol, Δ5-avenasterol and campesterol were the most representative sterols. Cholesterol, stigmasterol, clerosterol and Δ7-stigmastenol were also found in all samples. All studied samples respected EC Regulation N. 2568, and in all cases total sterols were remarkably higher than the minimum limit set by legislation, ranging from 2003 to 2682 mg/kg. Results were analysed with the help of several statistical techniques, including reduction of dimensionality by principal component analysis with cross-validation of the number of components, followed by the use of canonical variate predictive biplots for model development and canonical variate interpolative biplots for approximate classification of monovarietal and PDO olive oils. These biplots proved to be a very interesting solution in the present case study, overcoming the problems of interpretation and classification that arise whenever different multivariate analyses are coupled together