976 research outputs found
Understanding Brazilian Unemployment Structure: A Mixed Autoregressive Approach
The aims of this paper are estimate and forecast the Non-Accelerating Inflation Rate of Unemployment, or NAIRU, for Brazilian unemployment time series data. In doing so, we introduce a methodology for estimating mixed additive seasonal autoregressive (MASAR) models, by the Generalized Method of Moments (GMM). Furthermore, in order to cover a lack in econometric literature, an asymptotic theory for the Yule-Walker estimators of autoregressive parameters is developed. The paper provides some insights on estimating MASAR models when one of its component has a possible unit root. The obtained results are consistent to the literature and produce reasonable forecasts for NAIRU.Time series, Inflation, NAIRU, Seasonality, Unit Root
Efeitos do metilglioxal e da piridoxamina na bioenergética e no estado redox de mitocôndrias de cérebro de rato
Trabalho final de mestrado integrado em Medicina, área científica de Fisiologia, apresentado á Faculdade de Medicina da Universidade de CoimbraOs produtos finais de glicação avançada (AGEs) são formados a partir da reação não enzimática entre açúcares redutores e grupos amina de proteínas, lípidos e ácidos nucléicos. Os AGEs estão implicados na patogénese da diabetes e das complicações e no processo fisiológico do envelhecimento, sendo o metilglioxal (MG) um dos principais intermediários dos AGEs. O objetivo deste estudo foi investigar os efeitos da administração crónica de MG e do tratamento com piridoxamina (PM), um derivado da vitamina B6 com capacidade de inibir a glicação, na bioenergética e no estado oxidativo das mitocôndrias de cérebro. Para tal, foram criados 4 grupos de ratos: 1) ratos Wistar controlo; 2) ratos Wistar tratados com MG, por via oral, durante 10 semanas (50 mg MG/Kg peso corporal/dia nas primeiras 6 semanas e 60 mg MG/Kg peso corporal/dia nas últimas 4 semanas); 3) ratos tratados com MG (protocolo anterior) e, posteriormente, tratados com 1g/l PM, por via oral, durante 4 semanas e 4) ratos Wistar tratados apenas com 1g/l PM, por via oral, durante 4 semanas. Findo os períodos de tratamento, os animais foram sacrificados e as mitocôndrias de cérebro isoladas. Avaliámos vários parâmetros mitocondriais: a cadeia respiratória [estados 3 e 4 da respiração, índice de controlo respiratório (ICR), e razão ADP/O], o sistema fosforilativo [potencial transmembranar (m), despolarização induzida pelo APD, tempo de repolarização e níveis de ATP], a atividade da aconitase mitocondrial e das enzimas antioxidantes glutationa peroxidase (GPx), glutationa redutase (GR) e superóxido dismutase dependente de manganês (MnSOD), os níveis de peróxido de hidrogénio (H2O2), de malondialdeído (MDA; marcador de peroxidação lipídica) e de glutationa e vitamina E (-tocoferol) (antioxidantes não enzimáticos). O tratamento com MG provocou um decréscimo significativo do ICR, da razão ADP/O e das atividades da aconitase e GR e aumentou os níveis de H2O2. O tratamento com
PM não contrariou os efeitos deletérios do MG e, além disso, a PM levou a um decréscimo significativo do m e do ICR. Por outro lado, a administração da PM a ratos controlo diminuiu significativamente a atividade da aconitase mitocondrial e os níveis de MDA e aumentou a razão ADP/O, a despolarização induzida pelo ADP, os níveis de α-tocoferol e as atividades da GPx e MnSOD. Não foram observadas alterações significativas nos outros parâmetros analisados. Concluindo, os nossos resultados mostram que níveis elevados de MG têm efeitos deletérios na função e estado oxidativo das mitocôndrias de cérebro e que a PM foi incapaz de reverter os efeitos do MGAdvanced glycation end products (AGEs) are originated by a non-enzymatic reaction between reducing sugars and amino groups of proteins, lipids and nucleic acids. AGEs are involved in aging, age-related diseases and diabetes-associated complications, methylglyoxal (MG) being an important precursor in AGEs formation. This study was intended to investigate the effects of chronic administration of MG and treatment with pyridoxamine (PM), a powerful glycation inhibitor that belongs to vitamin B6 family, on brain mitochondrial bioenergetics and oxidative status. For that purpose, 4 groups of rats were created: 1) a group of control Wistar rats; 2) a group of Wistar rats orally treated with MG during 10 weeks (first 6 weeks with 50 mg MG/Kg body weight/day and the last 4 weeks with 60 mg MG/Kg body weight/day); 3) a group of Wistar rats treated with MG (same protocol as before) and then orally treated with 1g/l of PM during 4 weeks and 4) Wistar rats treated only with 1g/l of PM during 4 weeks. After the treatment periods, the animals were sacrificed and the brain mitochondrial fractions were obtained. We evaluated several mitochondrial parameters: the respiratory chain [states 3 and 4 of respiration, respiratory control ratio (RCR), and ADP/O index], the phosphorylation system, [transmembrane potential (ΔΨm), ADP-induced depolarization, repolarization lag phase and ATP levels], the activity of mitochondrial aconitase and antioxidant enzymes glutathione peroxidase (GPx), glutathione reductase (GR) and manganese superoxide dismutase (MnSOD), the levels of hydrogen peroxide (H2O2), malondialdehyde (MDA), and glutathione and vitamin E (-tocoferol) (non-enzymatic antioxidants). MG treatment induced a statistical significant decrease in RCR, ADP/O index and activity of aconitase and GR and an increase in H2O2 levels. The administration of PM to MG-treated rats did not counteract those effects and, additionally,
promoted a significant decrease in m and RCR. Furthermore, its administration to the control group caused a significant decrease in the activity of aconitase, in MDA levels and significantly increased ADP/O index, α-tocopherol levels and the activity of both GPx and MnSOD. No statistically significant changes were observed in the other parameters analysed. In conclusion, our results show that chronic exposure to MG had deleterious effects in the function and oxidative status of brain mitochondria, and that PM was unable to reverse the effects of M
Global and local detection of liver steatosis from ultrasound
Liver steatosis is a common disease usually associated with social and genetic factors. Early detection and quantification is important since it can evolve to cirrhosis. Steatosis is usually a diffuse liver disease, since it is globally affected. However, steatosis can also be focal affecting only some foci difficult to discriminate. In both cases, steatosis is detected by laboratorial analysis and visual inspection of ultrasound images of the hepatic parenchyma. Liver biopsy is the most accurate diagnostic method but its invasive nature suggest the use of other non-invasive methods, while visual inspection of the ultrasound images is subjective and prone to error. In this paper a new Computer Aided Diagnosis (CAD) system for steatosis classification and analysis is presented, where the Bayes Factor, obatined from objective intensity and textural features extracted from US images of the liver, is computed in a local or global basis. The main goal is to provide the physician with an application to make it faster and accurate the diagnosis and quantification of steatosis, namely in a screening approach. The results showed an overall accuracy of 93.54% with a sensibility of 95.83% and 85.71% for normal and steatosis class, respectively. The proposed CAD system seemed suitable as a graphical display for steatosis classification and comparison with some of the most recent works in the literature is also presented
An ultrasound based computer-aided diagnosis tool for steatosis detection
Liver steatosis is a common disease usually associated with social and genetic factors. Early detection and quantification is important since it can evolve to cirrhosis. In this paper, a new computer-aided diagnosis (CAD) system for steatosis classification, in a local and global basis, is presented. Bayes factor is computed from objective ultrasound textural features extracted from the liver parenchyma. The goal is to develop a CAD screening tool, to help in the steatosis detection. Results showed an accuracy of 93.33%, with a sensitivity of 94.59% and specificity of 92.11%, using the Bayes classifier. The proposed CAD system is a suitable graphical display for steatosis classification
Cisalhamento em vigas de concreto de alta resistencia com adição de fibras de aço submetidas a carregamentos reversos
Orientador: Armando Lopes Moreno JrDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia CivilResumo: Neste trabalho, apresentam-se os resultados de uma investigação experimental sobre o comportamento ao cisalhamento por força cortante de vigas de concreto armado reforçado com fibras de aço submetidas à carregamento reverso. Foram analisadas doze vigas, onde todas apresentaram a mesma geometria, armadura longitudinal e transversal e tendo como variantes a resistência à compressão do concreto, a presença ou não de fibras de aço e o tipo de carregamento que a viga foi submetida (normal ou invertido). Os resultados obtidos nos ensaios, permitiram analisar o comportamento ao cisalhamento de cada viga e também quantificar parcela de contribuição do concreto (Vc), na resistência ao esforço cortante, com a adição de fibras ou com inversão de carregamentoAbstract: This work presents a theoretical summary about shear in reinforced concrete beams with addition the steel fiber submitted the reverse loading. Twelve beams were analyzed, where alI presented the same geometry, longitudinal and shear reinforcement and tends as variants the strength compression of the concrete, the presence or not of fibers of steel and the loading type that the beam was submitted (normal or inverted). The results obtained in the rehearsals, they allowed to analyze the behavior to the shear of each beam and also to quantify portion of contribution of the concrete (V c), in the strength shear, with the addition of fibers or with reverse loadingMestradoEstruturasMestre em Engenharia Civi
A formação continuada de professores de música no contexto da educação nacional
Este artigo apresenta reflexões acerca das perspectivas para a formação continuada de professores da educação básica no atual cenário político-educacional do país, dimensionando essa realidade para a área de educação musical. O trabalho abrange ainda resultados obtidos a partir da realização de um projeto de formação continuada para professores de música, que contemplou, especificamente, profissionais atuantes no ensino fundamental da rede municipal de João Pessoa-PB. As discussões e análises apresentadas neste artigo têm como base pesquisa bibliográfica e documental que abrangeu publicações e registros diversos relacionadas à formação continuada no Brasil, bem como dados empíricos coletados, junto aos professores participantes do Projeto, a partir de entrevistas, gravações de áudio e de vídeo e fotografias. O estudo pôde evidenciar as concepções e práticas dos professores de música atuantes em João Pessoa, destacando a importância da formação continuada para o fortalecimento das ações docentes no contexto da educação básica
Understanding the role of local tourist actors as online destination promoters: the “Terras de Trás-os-Montes” case
Local communities are taking an increasingly major role in communicating a destination in
terms of contact with tourists. Based on the assumption that tourist entities and agents are
part of this community, it can be assumed that it is necessary for the territorial marketing
regulators to promote their involvement. This communication is progressively generated
through information and communication technologies (ICT), namely social networks. To
analyze the communication contribution of the tourist entities of the Trás-os-Montes lands
(a region in the northeast part of Portugal), an analysis was carried out on the online
presence and its way of communicating the region. The findings offer relevant insights for
the destination managers and policy makers.info:eu-repo/semantics/publishedVersio
In-season internal and external training load quantification of an elite European soccer team
Elite soccer teams that participate in European competitions need to have players in the best physical and psychological status possible to play matches. As a consequence of congestive schedule, controlling the training load (TL) and thus the level of effort and fatigue of players to reach higher performances during the matches is therefore critical. Therefore, the aim of the current study was to provide the first report of seasonal internal and external training load that included Hooper Index (HI) scores in elite soccer players during an in-season period. Nineteen elite soccer players were sampled, using global position system to collect total distance, high-speed distance (HSD) and average speed (AvS). It was also collected session rating of perceived exertion (s-RPE) and HI scores during the daily training sessions throughout the 2015-2016 in-season period. Data were analysed across ten mesocycles (M: 1 to 10) and collected according to the number of days prior to a one-match week. Total daily distance covered was higher at the start (M1 and M3) compared to the final mesocycle (M10) of the season. M1 (5589m) reached a greater distance than M5 (4473m) (ES = 9.33 [12.70, 5.95]) and M10 (4545m) (ES = 9.84 [13.39, 6.29]). M3 (5691m) reached a greater distance than M5 (ES = 9.07 [12.36, 5.78]), M7 (ES = 6.13 [8.48, 3.79]) and M10 (ES = 9.37 [12.76, 5.98]). High-speed running distance was greater in M1 (227m), than M5 (92m) (ES = 27.95 [37.68, 18.22]) and M10 (138m) (ES = 8.46 [11.55, 5.37]). Interestingly, the s-RPE response was higher in M1 (331au) in comparison to the last mesocycle (M10, 239au). HI showed minor variations across mesocycles and in days prior to the match. Every day prior to a match, all internal and external TL variables expressed significant lower values to other days prior to a match (p<0.01). In general, there were no differences between player positions. Conclusions: Our results reveal that despite the existence of some significant differences between mesocycles, there were minor changes across the in-season period for the internal and external TL variables used. Furthermore, it was observed that MD-1 presented a reduction of external TL (regardless of mesocycle) while internal TL variables did not have the same record during in-season match-day-minus.: The authors state that there were no salaries’ fund from a tobacco company. Also, the authors are not aware of any competing interests. This project was supported by the National Funds through FCT—Portuguese Foundation for Science and Technology (UID/DTP/04045/2013)—and the European Fund for Regional Development (FEDER) allocated by European Union through the COMPETE 2020 Programme (POCI-01-0145- FEDER-006969)—competitiveness and internationalization (POCI). All funding received for this work from any of the following organizations: National Institutes of Health (NIH); Welcome Trust; Howard Hughes Medical Institute (HHMI). The
funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio
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