Supercritical CO2 extraction of secondary metabolites from Agaricus blazei: experiments and modelling

The mycelium and young fruiting bodies of Agaricus blazei were submitted to supercritical CO2 extraction, in a modified commercial flow apparatus, at temperatures from 40 to 80 ºC, pressures up to 600 bar and CO2 flow-rates from 2.0 to 9.0 g.min-1. The best extraction conditions of secondary metabolites, whereby the degree of solubilization (g extract/100 g of fungi) is the highest, was obtained with pure CO2 at 400 bar, 70 ºC and a CO2 flow rate of 5.7g.min-1. The extract in that conditions were analysed by GC-Ms. In order to increase the extraction yield of secondary metabolites, which are mostly present in glycolipid fractions, a polar compound (ethanol) was used as co-solvent in the proportions of 5 and 10 % (mol/mol). The presence of ethanol increased the yield when compared with the extraction with pure CO2. Moreover, a simple model was applied to the supercritical CO2 extraction of secondary metabolites from Agaricus blazei.

Occupational exposure to Aflatoxin B1 in Portuguese swine farms

Aflatoxins were first isolated about 40 years ago afier outbreaks of disease and death in turkeys and cancer in rainbow trout fed with rations formulated from peanut and cottonseed meals. These toxins are secondary metabolites produced under certain conditions of temperature, p14 and humidity predominantiy by Aspergilius flavus and Aspergilius parasiticus fungi species. Among 18 different types of aflatoxins identified, major members are aflatoxin B1, B2, G1 and G2. Aflatoxin B1 (AFB1) is normaily predominant in cultures as well as in food products. AFB1 was shown to be genotoxic and a potent hepatocarcinogen. This mycotoxin is metabolized by the mixed function oxidase system to a number of hydroxylated metabolites including the 8,9-epoxide. The latter is considered to be the ultimate carcinogen that reacts with cellular deoxyribonucleic acid (DNA) and proteins to form covalent adducts.

Occupational exposure to toxigenic fungi from Aspergillus flavus complex

Bioaerosols are mainly composed of fungal particles, bacteria and plant spores, being fungi responsible for the release of VOCs and micotoxins into indoor environments. Aspergillus flavus is a common opportunistic pathogen causing human infections and is involved in the production of aflatoxin and other secondary metabolites associated with toxic and allergic reactions. Poultry workers are exposed to high concentrations of fungi and are therefore more prone to develop associated pathologies. To evaluate occupational exposure of the workers to Aspergillus flavus and aflatoxins, six animal production facilities were selected, including 10 buildings, from which indoor air samples and outdoor reference samples were obtained. Twenty-five duplicate samples were collected by two methodologies: impactation onto malt extract agar of 25L air samples using a Millipore Air Tester were used to evaluate quantitative (CFU/m3) and qualitative (species identification, whenever possible) sample composition; 300 L air samples collected with the Coriolis Air Sampler into phosphate–saline buffer were used to isolate DNA, following molecular identification of Aspergillus section flavi using nor-1 specific primers by real-time PCR.

Fungi distribution in poultry feed

Feed can easily be contaminated and colonized by fungi that use up the nutrients for their own metabolism and growth, producing secondary metabolites such as mycotoxins that are not eliminated throughout the feed processing. The major problems associated with mycotoxin contaminated animal feed are metabolic disturbances resulting in poor animal productivity. In addition, handling contaminated animal feed can also raise health issues regarding workers exposure to fungi and mycotoxins. The scope of this work was to characterize fungal distribution in 11 poultry feed samples. Twenty grams of feed were suspended in 180 mL of distilled water and homogenized during 20 minutes at 200 rpm. The washed supernatant was plated in malt extract agar (MEA) and dichloran glycerol agar base (DG18) media for morphological identification of the mycobiota present. Using macro- and microscopic analysis of the colonies, fungal contamination was evident in 72.7% of the analyzed poultry feed samples. Fungal load ranged from 0 to 13140 CFU/g, and the most prevalent species/genera were F. graminearum complex (71.1%), Penicillium sp. (11.6%), Cladosporium sp. (8.8%), and Fusarium poae (3.6%). In addition to these species, we also isolated Aspergillus sections Circumdati, Nigri and Aspergilli, and Mucor and Rhizopus genus albeit at a lower abundance. The data obtained showed that, besides high fungal contamination, mycotoxins contamination is probably a reality, particularly in the final product since mycotoxins resist to all the processing operations including thermal treatment. Additionally, data claimed attention for the probable co-exposure to fungi and mycotoxins of the workers in feed industries.

The importance of quality of life in patients with multiple sclerosis: do they need auxiliary walking devices?

Objective: To describe the importance of training multiple sclerosis (MS) patients with auxiliary walking devices (walking stick, crutch, or wheelchair) in a way that achieves a better quality of life (QOL). Design: Exploratory and descriptive. Setting: General hospital in Portugal.

Risk assessment of exposure to multiple mycotoxins in food

Moulds may produce a diversity of toxins such as aflatoxins, ochratoxins, trichothecenes, zearalenone, fumonisins and others. Although toxicological, environmental and epidemiological studies have addressed the problem of these toxins one by one, more than one mycotoxin are found usually in the same contaminated food. Risk assessment for humans potentially exposed to multimycotoxins suffers very much from the lack of adequate food consumption data. Furthermore, for a given mycotoxin, synergism and antagonism with other mycotoxins, found in the same food commodities, are not taken into account. Aflatoxin B1 and ochratoxin A belong to the most frequently occurring mycotoxins. This has repeatedly been demonstrated, however, normally, the risk resulting from their simultaneous occurrence is not considered. A descriptive study was developed to monitor air fungal contamination in one hospital food unit.

The importance of the program for the promotion of physical activity in perceived fatigue in people with multiple sclerosis

The aims of the study is to examine for intervention program of physical activity in the perception of fatigue, in patients with multiple sclerosis.

Implication of an intervention program for the promotion of physical activity in the quality of life of people with multiple sclerosis

The aims of this study is to examine the interest for quality of life of an implementation of program physical activity, with patients of multiple sclerosis.

Augmented LDPC Graph for Distributed Video Coding with Multiple Side Information

The advances made in channel-capacity codes, such as turbo codes and low-density parity-check (LDPC) codes, have played a major role in the emerging distributed source coding paradigm. LDPC codes can be easily adapted to new source coding strategies due to their natural representation as bipartite graphs and the use of quasi-optimal decoding algorithms, such as belief propagation. This paper tackles a relevant scenario in distributedvideo coding: lossy source coding when multiple side information (SI) hypotheses are available at the decoder, each one correlated with the source according to different correlation noise channels. Thus, it is proposed to exploit multiple SI hypotheses through an efficient joint decoding technique withmultiple LDPC syndrome decoders that exchange information to obtain coding efficiency improvements. At the decoder side, the multiple SI hypotheses are created with motion compensated frame interpolation and fused together in a novel iterative LDPC based Slepian-Wolf decoding algorithm. With the creation of multiple SI hypotheses and the proposed decoding algorithm, bitrate savings up to 8.0% are obtained for similar decoded quality.

OC/EC ratio observations in Europe: Re-thinking the approach for apportionment between primary and secondary organic carbon

This study explores a large set of OC and EC measurements in PM(10) and PM(2.5) aerosol samples, undertaken with a long term constant analytical methodology, to evaluate the capability of the OC/EC minimum ratio to represent the ratio between the OC and EC aerosol components resulting from fossil fuel combustion (OC(ff)/EC(ff)). The data set covers a wide geographical area in Europe, but with a particular focus upon Portugal, Spain and the United Kingdom, and includes a great variety of sites: urban (background, kerbside and tunnel), industrial, rural and remote. The highest minimum ratios were found in samples from remote and rural sites. Urban background sites have shown spatially and temporally consistent minimum ratios, of around 1.0 for PM(10) and 0.7 for PM(2.5).The consistency of results has suggested that the method could be used as a tool to derive the ratio between OC and EC from fossil fuel combustion and consequently to differentiate OC from primary and secondary sources. To explore this capability, OC and EC measurements were performed in a busy roadway tunnel in central Lisbon. The OC/EC ratio, which reflected the composition of vehicle combustion emissions, was in the range of 03-0.4. Ratios of OC/EC in roadside increment air (roadside minus urban background) in Birmingham, UK also lie within the range 03-0.4. Additional measurements were performed under heavy traffic conditions at two double kerbside sites located in the centre of Lisbon and Madrid. The OC/EC minimum ratios observed at both sites were found to be between those of the tunnel and those of urban background air, suggesting that minimum values commonly obtained for this parameter in open urban atmospheres over-predict the direct emissions of OC(ff) from road transport. Possible reasons for this discrepancy are explored. (C) 2011 Elsevier Ltd. All rights reserved.

Environmental and track perturbations on multiple pantograph interaction with catenaries in high-speed trains

The top velocity of high-speed trains is generally limited by the ability to supply the proper amount of energy through the pantograph-catenary interface. The deterioration of this interaction can lead to the loss of contact, which interrupts the energy supply and originates arcing between the pantograph and the catenary, or to excessive contact forces that promote wear between the contacting elements. Another important issue is assessing on how the front pantograph influences the dynamic performance of the rear one in trainsets with two pantographs. In this work, the track and environmental conditions influence on the pantograph-catenary is addressed, with particular emphasis in the multiple pantograph operations. These studies are performed for high speed trains running at 300 km/h with relation to the separation between pantographs. Such studies contribute to identify the service conditions and the external factors influencing the contact quality on the overhead system. (C) 2013 Elsevier Ltd. All rights reserved.

Decisions with multiple simultaneous goals and uncertain causal effects

A key aspect of decision-making in a disaster response scenario is the capability to evaluate multiple and simultaneously perceived goals. Current competing approaches to build decision-making agents are either mental-state based as BDI, or founded on decision-theoretic models as MDP. The BDI chooses heuristically among several goals and the MDP searches for a policy to achieve a specific goal. In this paper we develop a preferences model to decide among multiple simultaneous goals. We propose a pattern, which follows a decision-theoretic approach, to evaluate the expected causal effects of the observable and non-observable aspects that inform each decision. We focus on yes-or-no (i.e., pursue or ignore a goal) decisions and illustrate the proposal using the RoboCupRescue simulation environment.

Implications of the Intervention Program for Physical Activity (IPPA) in the perception of illness and wellbeing in people with Multiple Sclerosis (MS)

The aim of this study is to examine the implications of the IPPA in the perception of illness and wellbeing in MS patients. Methods - This is a quasi experimental study non-randomized study with 24 MS patients diagnosed at least 1 year before, and with an EDSS score of under 7. We used the IPPA in 3 groups of eight people in 3 Portuguese hospitals (Lisbon, Coimbra, and Porto). The sessions were held once a week for 90 minutes, over a period of 7 weeks. The instruments used were: We asked the subjects the question “Please classify the severity of your disease?” and used the Personal Wellbeing Scale (PWS) at the beginning (time A) and end (time B) of the IPPA. We used the SPSS version 20. A non-parametric statistical hypothesis test (Wilcoxon test) was used for the variable analysis. The intervention followed the recommendations of the Helsinki Declaration. Results – The results suggest that there are differences between time A and B, the perception of illness decreased (p<0.08), while wellbeing increased (p<0.01). Conclusions: The IPPA can play an important role in modifying the perception of disease severity and personal wellbeing.

Práticas de literacia e avaliação da competência da escrita

O desfasamento entre a escola e os diferentes contextos sociais em que se insere, a dificuldade em dar resposta às solicitações e desafios que as suas comunidades lhe colocam, a deficiente preparação de muitos dos alunos para um uso competente e crítico da linguagem oral e escrita, constituem três críticas sérias ao papel atual da escola. O projeto que estamos a dinamizar com uma turma do ensino secundário procura contrariar este rumo da educação, demonstrando que é possível construir e valorizar as competências de literacia que não se circunscrevem à própria vida escolar, através de atividades de aprendizagem efetiva da escrita, numa relação interdisciplinar com outras áreas de conhecimento. Ele surge nos antípodas do ensino tradicional, onde a produção escrita é imposta aos alunos, tendo quase sempre o professor como único destinatário, valorizando-se aspetos de natureza formal e superficial em detrimento de outros que são fundamentais em termos de eficácia discursiva, fazendo dela depender, quase exclusivamente, a avaliação do aluno, muitas vezes assente numa mera reprodução de conhecimento.Assim, e com recurso à metodologia do trabalho de projeto, concebemos um roteiro paisagístico, ainda em fase de realização, acerca de uma quinta de D. Antónia (Ferreirinha), destinado aos seus turistas, que tem obrigado a uma participação no quadro mais alargado da escola enquanto comunidade e nas comunidades em que os seus membros se inserem, fazendo com que os alunos interajam com os contextos culturais, históricos, económicos, sociais e institucionais onde atuam, estudam e vivem: o Douro. Nesta comunicação, procuramos divulgar estas práticas e discutir a sua viabilidade, evidenciando o modo como os alunos constroem o seu saber sobre a língua e de que modo a avaliação é um processo indispensável quer nas diferentes etapas de elaboração de um projeto, quer no domínio da competência de escrita.