Showing papers by "Polytechnic Institute of Viseu published in 2013"

Chemical changes of heat treated pine and eucalypt wood monitored by FTIR

Abstract: A hardwood, Eucalyptus globulus Labill, and a softwood Pinus pinaster Aiton, were heat treated at temperatures between 170 and 210oC in an oven and in an autoclave The samples were pre-extracted with dichloromethane, ethanol and water and ground prior to Fourier Transform Infrared (FTIR) spectroscopic analysis The heat treatment caused significant changes in the chemical composition and structure of wood, in lignin and polysaccharides Hemicelluloses were the first to degrade as proved by the initial decrease of the 1730 cm-1 peak due to the breaking of acetyl groups in xylan Hardwood lignin changed more than softwood lignin, with a shift of maximum absorption from 1505 cm-1 to approximately 1512 cm-1 due to decrease of methoxyl groups, loss of syringyl units or breaking of aliphatic side-chains The macromolecular structure becomes more condensed and there is a clear increase of non-conjugated (1740 cm-1) in relation to conjugated groups (1650 cm-1) However, the changes induced by the thermal treatment are difficult to monitor by FTIR spectroscopy due to the different chemical reactions occurring simultaneously

Diabetes abrogates sex differences and aggravates cardiometabolic risk in postmenopausal women

Abstract: The aim of this study is to evaluate the effect of gender and menopause in cardiometabolic risk in a type 2 diabetes mellitus (T2DM) population, based on classical and non-traditional markers. Seventy four volunteers and 110 T2DM patients were enrolled in the study. Anthropometric data, blood pressure, body mass index (BMI), waist circumference (WC) and the following serum markers were analyzed: glucose, Total-c, TGs, LDL-c, Oxidized-LDL, total HDL-c and large and small HDL-c subpopulations, paraoxonase 1 activity, hsCRP, uric acid, TNF-α, adiponectin and VEGF. Non-diabetic women, compared to men, presented lower glycemia, WC, small HDL-c, uric acid, TNF-α and increased large HDL-c. Diabetes abrogates the protective effect of female gender, since diabetic women showed increased BMI, WC, small HDL-c, VEGF, uric acid, TNF-α and hsCRP, as well as reduced adiponectin, when compared with non-diabetic. In diabetic females, but not in males, WC is directly and significantly associated with TNF-α, VEGF, hsCRP and uric acid; TNF-α is directly associated with VEGF and hsCRP, and inversely with adiponectin. Postmenopausal females presented a worsen cardiometabolic profile, viewed by the increased WC, small HDL-c, VEGF, uric acid, TNF-α and hsCRP. In this population, WC is directly and significantly associated with TNF-α, VEGF, hsCRP; TNF-α is directly associated with VEGF; and uric acid is inversely associated with large HDL-c and hsCRP with adiponectin, also inversely. Diabetes abrogates the protective effect of gender on non-diabetic women, and postmenopausal diabetic females presented worsen cardiometabolic risk, including a more atherogenic lipid sketch and a pro-inflammatory and pro-angiogenic profile. The classical cardiovascular risk factors (CVRFs) fail to completely explain these differences, which are better clarified using “non-traditional” factors, such as HDL-c subpopulations, rather than total HDL-c content, and markers of inflammation and angiogenesis, namely TNF-α, hsCRP, uric acid and VEGF. Multi-therapeutic intervention, directed to obesity, atherogenic lipid particles and inflammatory mediators is advisory in order to efficiently prevent the serious diabetic cardiovascular complications.

Place-attachment, destination image and impacts of tourism in mountain destinations

Abstract: Tourism mountain destinations are places with powerful symbolic features that exert strong influence on destination image formation. They are, particularly, apt to create strong links with the people who visit them. In addition, mountains are nature spaces that are particularly vulnerable to the effects of tourism development, more or less visible to visitors. The present study analyses, in a holistic and multidisciplinary approach, the relation between perceptions of tourism impacts, tourists' destination image, and their place-attachment regarding mountain destinations. Based on data collected in a survey of 315 tourists visiting three European mountain areas – Peaks of Europe (Spain), the Alps (France, Austria, and Switzerland), and Serra da Estrela (Portugal), the relationship between these variables was analysed, using structural equation modelling. The structural model reveals that tourists' perceptions towards tourism development in mountain destinations affect their cognitive and affective destina...

English Premier League, Spaińs La Liga and Italýs Seriés A – What’s Different?

Abstract: Our study aimed to understand which aspects are most important by coaches in the characterization of the three best European Football Leagues (English Premier League, Spains La Liga and Italýs Seri...

Analysis of the physical-chemical and sensorial properties of Maria type cookies

Abstract: Given the importance of the cookies of type Maria worldwide, and considering the absence of any scientific study setting out their main features, it becomes important to identify the differentiating characteristics of several commercialized brands, in particular related to the chemical, physical and sensory characteristics. In this way, the aim of this work was to study and compare eight different brands of cookies of type Maria. The elemental chemical analysis (moisture, ash, protein, fat, fibre and carbohydrates contents), determination of physical parameters (volume, density, texture and colour) and sensory evaluation of studied cookies were performed. Multivariate statistical methods (Pearson correlation, principal component analysis and cluster analysis) were applied to estimating relationships in analysed data. The results for the elemental analysis showed that the samples were very similar in terms of some components, like for example ashes, while quite different in terms of other components, such as moisture and fat contents. With respect to texture and colour the samples showed, in general, some important differences. In terms of sensory evaluation, the sample C was the one that in most sensory tests gathered the preference of the panellists. The cluster analysis showed that the sample A was much different from the other samples. The results of principal component analysis showed that the main component explains 32.6 % of the total variance, and is strongly related to variables associated to colour.

Presence of antibodies against genogroup VI norovirus in humans.

Abstract: Background: Noroviruses are important enteric pathogens in humans and animals. Recently, we reported a novel canine norovirus (CaNoV) in dogs with diarrhea belonging to a new genogroup (GVI). No data are available on exposure of humans to this virus. Methods: Sera from 373 small animal veterinarians and 120 age-matched population controls were tested for IgG antibodies to CaNoV by a recombinant virus like particle based enzyme-linked immunosorbent assay. Results: Antibodies to CaNoV were found in 22.3% of the veterinarians and 5.8% of the control group (p < 0.001). Mean corrected OD450 values for CaNoV antibodies were significantly higher in small animal veterinarians compared to the control group.

In vivo and in vitro effects of RAD001 on bladder cancer

Abstract: Objective: To evaluate the influence of Everolimus (RAD001) on chemically induced urothelial lesions in mice and its influence on in vitro human bladder cancer cell lines. Methods: ICR male mice were given N-butyl-N-(4-hydroxybutyl) nitrosamine in drinking water for a period of 12 weeks. Subsequently, RAD001 was administered via oral gavage, for 6 weeks. At the end of the experiment, all the animals were sacrificed and tumor development was determined by means of histopathologic evaluation; mammalian target of rapamycin (mTOR) expressivity was evaluated by immunohistochemistry. Three human bladder cancer cell lines (T24, HT1376, and 5637) were treated using a range of RAD001 concentrations. MTT assay, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and flow cytometry were used to assess cell proliferation, apoptosis index, and cell cycle analysis, respectively. Immunoblotting analysis of 3 cell line extracts using mTOR and Akt antibodies was performed in order to study the expression of Akt and mTOR proteins and their phosphorylated forms. Results: The incidence of urothelial lesions in animals treated with RAD001 was similar to those animals not treated. RAD001 did not block T24 and HT1376 cell proliferation or induce apoptosis. A reduction in cell proliferation rate and therefore G 0 /G 1 phase arrest, as well as a statistically significant induction of apoptosis (P 0.001), was only observed in the 5637 cell line. Conclusion: RAD001 seems not to have a significant effect on chemically induced murine bladder tumors. The effect of RAD001 on tumor proliferation and apoptosis was achieved only in superficial derived bladder cancer cell line, no effect was observed in invasive cell lines. © 2011 Elsevier Inc. All rights reserved.

Acute hepatitis E complicated by Guillain-Barre syndrome in Portugal, December 2012--a case report.

Abstract: Autochthonous hepatitis E virus (HEV) infection has been increasingly reported in Europe and the United States, mostly arising from genotype 3 and less frequently genotype 4. We report here on a patient with HEV genotype 3a infection complicated by Guillain-Barre syndrome in Portugal in December 2012. We draw attention to the diagnosis of autochthonous HEV infection and to its rare, but important, neurological complications.

Mitochondrial and liver oxidative stress alterations induced by N-butyl-N-(4-hydroxybutyl)nitrosamine: relevance for hepatotoxicity.

Abstract: The most significant toxicological effect of nitrosamines like N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) is their carcinogenic activity, which may result from exposure to a single large dose or from chronic exposure to relatively small doses. However, its effects on mitochondrial liver bioenergetics were never investigated. Liver is the principal organ responsible for BBN metabolic activation, and mitochondria have a central function in cellular energy production, participating in multiple metabolic pathways. Therefore any negative effect on mitochondrial function may affect cell viability. In the present work, ICR male mice were given 0.05% of BBN in drinking water for a period of 12 weeks and were sacrificed one week later. Mitochondrial physiology was characterized in BBN- and control-treated mice. Transmembrane electric potential developed by mitochondria was significantly affected when pyruvate–malate was used, with an increase in state 4 respiration observed for pyruvate–malate (46%) and succinate (38%). A decrease in the contents of one subunit of mitochondrial complex I and in one subunit of mitochondrial complex IV was also observed. In addition, the activity of both complexes I and II was also decreased by BBN treatment. The treatment with BBN increases the susceptibility of liver mitochondria to the opening of the mitochondrial permeability transition pore. This susceptibility could be related with the increase in the production of H2O2 by mitochondria and increased oxidative stress confirmed by augmented susceptibility to lipid peroxidation. These results lead to the conclusion that hepatic mitochondria are one primary target for BBN toxic action during liver metabolism. Copyright © 2011 John Wiley & Sons, Ltd.

Resilient routing in optical networks using SRLG-disjoint path pairs of min-sum cost

Abstract: Ensuring network survivability is of the utmost importance in today's networks. A Shared Risk Link Group (SRLG) is the set of links in the network that share a common physical resource subject to fault(s). This concept allows an upper layer the ability to implement SRLG diverse routing. Two algorithms, the Conflicting SRLG Exclusion (CoSE) and the Iterative Modified Suurballe's Heuristic (IMSH), will be shortly reviewed. The first solves the min-min problem and the second the min-sum problem, considering SRLG-disjoint paths. It will then be described a new version of CoSE, which will be designated as CoSE-MS, for solving the min-sum problem for SRLG diverse routing. Finally CoSE-MS and IMSH performance will be compared using random networks and an optical network. Results show that CoSE-MS is a good compromise between the quality of obtained solutions and the used CPU time.

Implication of Low HDL-c Levels in Patients with Average LDL-c Levels: A Focus on Oxidized LDL, Large HDL Subpopulation, and Adiponectin

Abstract: To evaluate the impact of low levels of high density lipoprotein cholesterol (HDL-c) on patients with LDL-c average levels, focusing on oxidative, lipidic, and inflammatory profiles. Patients with cardiovascular risk factors (n = 169) and control subjects (n = 73) were divided into 2 subgroups, one of normal HDL-c and the other of low HDL-c levels. The following data was analyzed: BP, BMI, waist circumference and serum glucose Total-c, TGs, LDL-c, oxidized LDL, total HDL-c and subpopulations (small, intermediate, and large), paraoxonase-1 (PON1) activity, hsCRP, uric acid, TNF- α , adiponectin, VEGF, and iCAM1. In the control subgroup with low HDL-c levels, significantly higher values of BP and TGs and lower values of PON1 activity and adiponectin were found, versus control normal HDL-c subgroup. However, differences in patients' subgroups were clearly more pronounced. Indeed, low HDL-c subgroup presented increased HbA1c, TGs, non-HDL-c, Ox-LDL, hsCRP, VEGF, and small HDL-c and reduced adiponectin and large HDL. In addition, Ox-LDL, large-HDL-c, and adiponectin presented interesting correlations with classical and nonclassical markers, mainly in the normal HDL-c patients' subgroup. In conclusion, despite LDL-c average levels, low HDL-c concentrations seem to be associated with a poor cardiometabolic profile in a population with cardiovascular risk factors, which is better evidenced by traditional and nontraditional CV biomarkers, including Ox-LDL, large HDL-c, and adiponectin.

Nutritional status in preschool children: current trends of mother's body perception and concerns

Abstract: Background Studies in several countries indicate that parents show little concern and aren’t much aware of the nutritional status of their children, and have the tendency to underestimate the overweight which may present a difficulty when promoting healthier life styles. The aim of this study was to identify maternal body image perceptions in preschool children and analyze its relationship with nutritional status and family social demographic variables. Methods A transversal and descriptive study was developed in a sample of 1424 preschool children and their mothers living in several parts of Portugal. The children were weighted and measured by trained personnel, the BMI was calculated and the nutritional status was classified according to the NCHS referential (CDC, 2000). 1 Mother's real and ideal body image perception from their children was evaluated according to Collins’ body image silhouettes (1991). 2 Results The ideal and real perception was translated in a negative index on both children's genders, however 67.2% of the mothers revealed accuracy of perception, while 22.3% had a negative and 12.8% a positive discrepancy, being this significant concerning gender and age of the children. Children's actual weight status (ie, 60.2% normal weight, 16.9% overweight, 17.4% obese and 5.5% underweight) was significantly different from their parents’ perceptions (ie, 52.3% normal weight, 27.5% overweight 0,6% obesity and 19.6% underweight) explaining in 25.9% the variability of this perception. Globally 42.3% has no discrepancy but 44.3% thinks that children were thin and 13.4% heavier. This difference is significant concerning the age and scholarship of the mothers but has no relation with the income and residence. Conclusion Despite signs of a positive trend, mothers continue to show difficulty in recognizing the children's nutritional status, so effective public health strategies to increase parents’ awareness could be the first step in an effort to prevent childhood obesity.

Study About the Knowledge and Attitudes of the Portuguese Population About Food Fibres

Abstract: The association between dietary fiber, health benefits and healthy food has been studied in recent years. The food industry, to accompany the strong interest shown by consumers, has placed at their disposal new products, rich in dietary fiber. This work intended to make a statistical analysis of the knowledge of the Portuguese population about fibres, and for that a survey was conducted of a sample of 182 individuals. Some topics covered included consumption habits, knowledge about fibres, means of dissemination and information, food labelling or the relationship between fibres and health, among others. The most relevant results indicate that only 13% of respondents eat two meals a day with vegetables and/or salads and 9% eat at least 3 pieces of fruit. Whole grains are never consumed by only 41% and 18% do so at least once a week. Around 35% of respondents know about the origin of fibres whereas 70% say there is a greater amount of fibre in legumes, fruit with skin and whole foods. The consultation of food labels is of interest to 80% of respondents, although the fibre content is not of interest for 43% of respondents. The vast majority (90%) of respondents have the notion that fibre intake contributes to the prevention and treatment of diseases. With this work it was concluded that the individuals in the survey reveal an insufficient level of knowledge about dietary fibre and that, although they give great importance to the role of fibres in treatment and prevention of diseases, the level of intake is too low.

General phenolic characterisation, individual anthocyanin and antioxidant capacity of matured red wines from two Portuguese Appellations of Origins.

Abstract: BACKGROUND The main aim of this work was to evaluate the general phenolic composition, individual anthocyanin content and total antioxidant capacity from 20 commercial matured red wine samples (vintage from 2005 to 2008) produced in two Appellations of Origin from the north of Portugal: Douro and Dao. RESULTS The results showed that the levels of general phenolic compounds, individual anthocyanins and antioxidant capacity in the 20 matured red wine samples analysed differed significantly. In addition, matured red wine samples aged in oak wood had a lower total individual anthocyanin content (from 13.85 to 56.79 mg L−1, averaging 46.13 mg L−1) than wines aged in bottle (from 25.93 to 252.82 mg L−1, averaging 94.17 mg L−1). The total antioxidant capacity values of the analysed wines showed quantitative differences among the values obtained from each antioxidant method applied as well as differences in the range of variation, especially for the values obtained by the DPPH method. CONCLUSION The wines used in this study constitute quite a heterogeneous group, made from different Portuguese red grape varieties, with diverse ages and two ageing processes (bottle and oak wood barrels); and accordingly, they showed important differences, especially in their phenolic composition. Finally, the oak wood ageing process before bottling had a negative effect in individual anthocyanins content in contrast to matured red wines submitted only to a bottle ageing process. © 2013 Society of Chemical Industry

Design of hot-mix recycled asphalt concrete produced in plant without preheating the reclaimed material

Abstract: In recent years, in Portugal, some road pavement rehabilitation projects used hot-mix recycled (HMR) asphalt concrete in plant as a technique to perform cost and environmentally effective pavement recycling. One of the main problems raised by the use of HMR is the direct use of mix design procedures developed for conventional asphalt concrete. This paper describes a mix design procedure and a case study carried out for HMR based on the mechanical performance of several blends, which are applicable to common practice in Portugal. The study designed a typical 0/25 bituminous mixture for the base layer, which incorporates up to 40% of reclaimed bituminous material, introduced into the plant mixer without previous heating. Based on the results, it can be stated that the level of confidence is comparable to that obtainable from conventional mixtures, provided that a proper mixture design and some construction directives are used.

Assessment of Family Functionality Among the Elderly With Chronic Illness

Abstract: The family APGAR scale was developed by Smilkstein, Ashworth, and Montano (1982). The satisfaction assessment of the elderly with chronic illness regarding family is essential. This study aims to describe the socio-demographic and clinical profile of elderly people with chronic illness and correlate with perceived family support. This is a cross-sectional, analytical study of 294 elderly people (51.4% female), patients at the Health Centre in the district of Viseu - Portugal, diagnosed with chronic illness (77.9% cardiovascular); Mean age was 72.22 ± 6.13, 70.7% were married and 52% had 4 years of schooling; Data was gathered using a questionnaire and the Family APGAR (Adaptation, Partnership, Growth, Affection and Resolve). In relation to family functionality, 18.7% perceive families as highly functional, 26.9% mildly dysfunctional and 54.4% severely dysfunction. There is a statistically significant relationship between the family APGAR and the presence of chronic illness ( p < 0.001). We found no statistical significance between the family APGAR and gender ( p = 0.26), age ( p = 0.26), marital status ( p = 0.32) and educational level ( p = 0.28). Economic, political and social changes in our society has an impact on the family and the support they provide which is manifested among vulnerable groups, as is the case of an elderly person with chronic illness. Thus, we propose specialised psychological support for this age group which is more vulnerable and without the needed support from within the family.

Antibodies to hepatitis E in Portuguese mothers and their newborns

Abstract: The high mortality of pregnant women is one of the main features of hepatitis E virus (HEV) infection in endemic countries. With the emergence of genotype 3 HEV in industrialized countries, attention should be given to pregnant women from these regions since the effect of genotype 3 HEV in pregnancy is not yet known. In this study, archived sera dating from 1993 from mothers with no history of traveling to HEV endemic countries and their newborns were tested for anti-HEV IgG antibodies. Four of the 12 maternal sera were positive for IgG anti-HEV, indicating exposure to this virus. Their newborns were also positive, showing higher anti-HEV IgG levels. Overall, these findings demonstrate not only an efficient transplacental transport of anti-HEV IgG, but also circulation of autochthonous HEV in Portugal in the early 1990s.

Mediation with Incomplete Information: Approaches to Suggest Potential Agreements

Abstract: In bilateral Negotiation Analysis, the literature often considers the case of complete information. In this context, since the negotiators know the value functions of both parties, it is not difficult to calculate the Pareto efficient solutions for the negotiation. Thus rational negotiators can reach agreement on this frontier. However, these approaches are not applied in practice when complete information is not available. The research question of our work is “It is possible to help negotiators achieving an efficient solution in the absence of complete information regarding the different parameters of the model?”. We propose to derive incomplete information about the preferences of negotiators from the statements they make and the offers they exchange during the negotiation process. We present and discuss three approaches that use this information in order to help a mediator proposing a better solution than the compromise the negotiators have reached or are close to reach.

Influence of Drying on the Properties of Pears of the Rocha Variety (Pyrus communis L.).

Abstract: Abstract Rocha pear (Pyrus communis L.) is the main cultivar produced in Portugal, usually consumed in fresh. However, the drying of the pear can be an opportunity for development and enables the provision of alternative products to consumers. This work evaluates the effect of drying on some chemical and physical properties of pears of the Rocha variety. Furthermore, the origin of the pears was also a variable studied. For the completion of this work, pears from five different locations were analysed in fresh and after convective air drying at two different temperatures, 40 and 60°C. The properties analysed were dimensions of pears in terms of height and diameter, total solids content, acidity, maturation index, processing yields, colour and textural attributes.The results showed that the peel had lower acidity and higher maturation index, when compared to the pulp and that drying greatly reduced acidity, either in the pulp or in the peel. However, this variation was not influenced by the drying temperature. With respect to colour, total colour differences between 25 and 50 were observed (for the dried pears in relation to the fresh) and in this case increasing the drying temperature caused evident variations in the peel but not in the pulp. As to the textural attributes, hardness and chewiness were the ones that showed the higher changes with drying, increasing considerably with drying temperature.

essay on the role of teachers' questioning in inquiry-based mathematics teaching

Abstract: This paper is an essay on the role of the mathematics teacher’s questioning in inquiry-based teaching. Questions are important communication tools that are used by the teacher for various purposes and underpin different visions of what it means to teach mathematics. Inquiry-based mathematics teaching has achieved relevance as a powerful alternative to direct teaching, which is inefficient in complying with current demands of mathematics learning. The paper constitutes a reflection on

E-Cadherin and β-Catenin Expression during Urothelial Carcinogenesis Induced by N-butyl-N-(4-hydroxybutyl) nitrosamine in Mice

Abstract: Background: The purpose of this study was to determine the efficacy of a combination of gemcitabine and sirolimus in a mouse model of invasive bladder cancer. Materials and Methods: Gemcitabine (50 mg/kg) and sirolimus (1.5 mg/kg) were administered to animals previously exposed to N-butyl-N-4(hydroxybutyl)nitrosamine in drinking water. Tumour development was determined by histopathological evaluation. Results: Both drugs were well tolerated by animals. The incidence of lesions in mice treated with gemcitabine was lower in comparison to those not treated, however this result was not statistically significant. The incidence of invasive bladder cancer in animals treated with sirolimus was statistically lower (20%) than in animals not treated (54%) (p=0.008). The results indicate that this drug combination has no statistical significance on the development of pre-neoplastic urothelial lesions and had only a minor impact on invasive bladder cancer incidence in mice. Conclusion: The combination of gemcitabine and sirolimus had only a marginal impact on invasive bladder cancer in a mouse model.