982 resultados para Cross-lingual Link Discovery
Resumo:
Introduction In Brazil, little data exist regarding the distribution of genotypes in relation to basal core promoter (BCP) and precore/core mutations among chronic hepatitis B virus (HBV) carriers from different regions of the country. The aim of this study was to identify HBV genotypes and the frequency of mutations at the BCP and precore/core region among the prevalent genotypes in chronic carriers from southern Brazil. Methods Nested-polymerase chain reaction (nested-PCR) products amplified from the S-polymerase gene, BCP and precore/core region from 54 samples were sequenced and analyzed. Results Phylogenetic analysis of the S-polymerase gene sequences showed that 66.7% (36/54) of the patients were infected with genotype D (D1, D2, D3), 25.9% (14/54) with genotype A (A1, A2), 5.6% (3/54) with subgenotype C2, and 2% (1/54) with genotype E. A comparison of virological characteristics showed significant differences between genotypes A, C and D. The comparison between HBeAg status and the G1896A stop codon mutation in patients with genotype D revealed a relationship between HBV G1896A precore mutants and genotype D and hepatitis B e antigen (HBeAg) seroconversion. Genotype D had a higher prevalence of the G1896A mutation and the presence of a thymine at position 1858. Genotype A was associated with a higher prevalence of the G1862T mutation and the presence of a cytosine at position 1858. Conclusions HBV genotype D (D3) is predominant in HBV chronic carriers from southern Brazil. The presence of mutations in the BCP and precore/core region was correlated with the HBV genotype and HBeAg negative status.
Resumo:
INTRODUCTION: The present study was designed to assess the occurrence of co-infection or cross-reaction in the serological techniques used for detecting the anti-Leishmania spp., -Babesia canis vogeli and -Ehrlichia canis antibodies in urban dogs from an area endemic to these parasites. METHODS: The serum samples from dogs were tested for the Babesia canis vogeli strain Belo Horizonte antigen and Ehrlichia canis strain São Paulo by immunofluorescence antibody test (IFAT) and by anti-Leishmania immunoglobulin G (IgG) antibody detection to assess Leishmania infection. We used the following four commercial kits for canine visceral leishmaniasis: ELISA, IFAT, Dual Path Platform (DPP) (Bio Manguinhos(r)/FIOCRUZ/MS) and a rK39 RDT (Kalazar Detect Canine Rapid Test; Inbios). RESULTS : Of 96 serum samples submitted to serological assays, 4 (4.2%) were positive for Leishmania as determined by ELISA; 12 (12.5%), by IFAT; 14 (14.6%) by rK39 RDT; and 20 (20.8%), by DPP. Antibodies against Ehrlichia and Babesia were detected in 23/96 (23.9%) and 30/96 (31.2%) samples, respectively. No significant association was identified between the results of tests for detecting Babesia or Ehrlichia and those for detecting Leishmania (p-value>0.05). CONCLUSIONS: In the present study, we demonstrated co-infection with Ehrlichia or Babesia and Leishmania in dogs from Minas Gerais (Brazil); we also found that the serological tests that were used did not cross-react.
Resumo:
We use a new data set to study the determinants of the performance of open–end actively managed equity mutual funds in 27 countries. We find that mutual funds underperform the market overall. The results show important differences in the determinants of fund performance in the USA and elsewhere in the world. The US evidence of diminishing returns to scale is not a universal truth as the performance of funds located outside the USA and funds that invest overseas is not negatively affected by scale. Our findings suggest that the adverse scale effects in the USA are related to liquidity constraints faced by funds that, by virtue of their style, have to invest in small and domestic stocks. Country characteristics also explain fund performance. Funds located in countries with liquid stock markets and strong legal institutions display better performance.
Resumo:
We have witnessed in recent years, an obvious effort by the competent European institutions, towards the harmonization of general law applicable to all Member States (MS's). Many developments have been registered in several areas of law, a europeanization process that aims to add value to cross-border transactions and, consequently, the internal market and european trade. This trend manifests itself in general to the private law level, and particularly in contract law. The extension of the field in which market participants - whether professionals or consumers - can act, must imperatively be articulated with a consequent wider protection. After all, the consumer is also a leading European purposes and its level should not be called into question for the sake of promoting trade. The link between the positions of two opposing parties, professionals and consumers, requires commitment and work reinforced by the institutions but only on that basis is consistent legislative production. The proposed Regulation on a Common European Sales Law of the sale, the European Commission, set focus to European contract law and raises questions about the relevance and necessity of such uniformity. An instrument for purposes of harmonization of European contract law, that can be applied to all cross-border consumer contracts, similar in all MS's certainly bring many benefits. However, its applicability and usefulness would depend on the level of protection that would provide, compared to the existing national rights. Would an optional instrument ensure the designs of a common law? Moreover, would a binding instrument be the best alternative in that sense? Keywords:
Resumo:
The purpose of this study was to explore the relationship between the intensity of acid reflux and severity of esophageal tissue damage in a cross-sectional study of patients with gastroesophageal reflux disease (GERD). Seventy-eight patients with were selected in accordance with the strict 24-hour ambulatory esophageal pHmetry (24h-pHM) criteria and distributed into three age groups: Group A: 14 - 24 years of age. Group B: 25 - 54; and Group C: 55 - 64. The 24h-pHM was carried out in accordance with DeMeester standardization, and the Savary-Miller classification for the diagnosis of reflux esophagitis was used. The groups were similar in 24h-pHM parameters (p > 0.05), having above normal values. For the study group as a whole, there was no correlation between age group and intensity of acid reflux, and there was no correlation between intensity of acid reflux and severity of esophageal tissue damage. However, when the same patients were sub-grouped in accordance with the depth of their epithelial injury and then distributed into age groups, there was a significant difference in esophagitis without epithelial discontinuity. Younger patients had less epithelial damage than older patients. Additionally, although there was a significant progression from the least severe to the moderate stages of epithelial damage among the age groups, there was no apparent difference among the age groups in the distribution between the moderate stages and most severe stages. The findings support the conclusion that the protective response of individuals to acid reflux varies widely. Continued aggression by acid reflux appears to lead to the exhaustion of individual mechanisms of epithelial protection in some patients, but not others, regardless of age or duration of the disease. Therefore, the diagnosis and follow-up of GERD should include both measurements of the quantity of refluxed acid and an assessment of the damage to the esophageal epithelium.
Resumo:
This work aimed to contribute to drug discovery and development (DDD) for tauopathies, while expanding our knowledge on this group of neurodegenerative disorders, including Alzheimer’s disease (AD). Using yeast, a recognized model for neurodegeneration studies, useful models were produced for the study of tau interaction with beta-amyloid (Aβ), both AD hallmark proteins. The characterization of these models suggests that these proteins co-localize and that Aβ1-42, which is toxic to yeast, is involved in tau40 phosphorylation (Ser396/404) via the GSK-3β yeast orthologue, whereas tau seems to facilitate Aβ1-42 oligomerization. The mapping of tau’s interactome in yeast, achieved with a tau toxicity enhancer screen using the yeast deletion collection, provided a novel framework, composed of 31 genes, to identify new mechanisms associated with tau pathology, as well as to identify new drug targets or biomarkers. This genomic screen also allowed to select the yeast strain mir1Δ-tau40 for development of a new GPSD2TM drug discovery screening system. A library of unique 138 marine bacteria extracts, obtained from the Mid-Atlantic Ridge hydrothermal vents, was screened with mir1Δ-tau40. Three extracts were identified as suppressors of tau toxicity and constitute good starting points for DDD programs. mir1Δ strain was sensitive to tau toxicity, relating tau pathology with mitochondrial function. SLC25A3, the human homologue of MIR1, codes for the mitochondrial phosphate carrier protein (PiC). Resorting to iRNA, SLC25A3 expression was silenced in human neuroglioma cells, as a first step towards the engineering of a neural model for replicating the results obtained in yeast. This model is essential to understand the mechanisms of tau toxicity at the mitochondrial level and to validate PiC as a relevant drug target. The set of DDD tools here presented will foster the development of innovative and efficacious therapies, urgently needed to cope with tau-related disorders of high human and social-economic impact.
Resumo:
ABSTRACT - Background: From a public health perspective, the study of socio-demographic factors related to physical activity is important in order to identify subgroups for intervention programs. Purpose: This study also aimed to identify the prevalence and the socio-demographic correlates related with the achievement of recommended physical activity levels. Methods: Using data from the European Social Survey round 6, physical activity and socio-demographic characteristics were collected from 39278 European adults (18271 men, 21006 women), aged 18-64 years, from 28 countries in 2012. Meeting physical activity guidelines was assessed using World Health Organization criteria. Results: 64.50% (63.36% men, 66.49% women) attained physical activity recommended levels. The likelihood of attaining physical activity recommendations was higher in age group of 55-64 years (men: OR=1.22, p<0.05; women: OR=1.66, p<0.001), among those who had completed high school (men: OR=1.28, p<0.01; women: OR=1.26, p<0.05), among those who lived in rural areas (men: OR=1.20, p<0.001; women: OR=1.10, p<0.05), and among those who had 3 or more people living at home (men: OR=1.40, p<0.001; women: OR=1.43, p<0.001). On the other hand, attaining physical activity recommendations was negatively associated with being unemployed (men: OR=0.70, p<0.001; women: OR=0.87, p<0.05), being a student (men: OR=0.56, p<0.001; women: OR=0.64, p<0.01), being a retired person (men: OR=0.86, p<0.05) and with having a higher household income (OR=0.80, p<0.001; women: OR=0.81, p<0.01). Conclusion: This research helped clarify that, as the promotion of physical activity is critical to sustain health and prevent disease, socio-demographic factors are important to consider when planning the increase of physical activity.
Resumo:
The immune system comprises of different cell types whose role is to protect us against pathogens. This thesis investigates a very important mechanism for our organism protection in a specific disorder: cross-presentation in Wiskott-Aldrich Syndrome (WAS). WAS is caused by loss-of-function mutations in the cytoskeletal regulator WASp and WAS patients suffer from eczema, thrombocytopenia, and immunodeficiency. X-linked neutropenia (XLN) is caused by gain-of-function mutations in WASp and XLN patients suffer from severe congenital neutropenia and immunodeficiency. This thesis was focused on the role of B and T lymphocytes and dendritic cells (DCs). This work will be divided into two main topics: 1) In the first part I studied the capacity of B cells to take up, degrade and present antigen. Moreover I studied the capacity of B cells to induce T cell proliferation. 2) In the second part, I studied T cell proliferation induced by dendritic cells. To increase our understanding about this mechanism, additional experiments were performed, including acidification capacity of CD8+ and CD8- DCs, reactive oxygen species (ROS) production since it is directly connected to acidification. These assays were measured by flow cytometry. Localization of Rac1 and Rac2 GTPases was assessed by confocal microscopy. Proliferation, acidification and ROS production assays were performed also with cells from X-linked neutropenia (XLN) mice. From this study we concluded that B cells cannot induce CD8+ T cell proliferation however they take up and present antigen. Moreover I have shown that increased cross-presentation by WASp KO DCs with ovalbumin is associated with decreased capacity to acidify endosomal compartment; and WASp KO CD8- DCs have increased Rac2 localization to the phagosome. XLN dendritic cells have similar acidification and ROS production capacity than wildtype cells. In conclusion, our data suggests that WASp regulates antigen processing and presentation in DCs.
Resumo:
The present study is a qualitative analysis of the tensions that occur in cross-functional teams (CFTs) and the way in which they can affect the teams' accomplishments. The research is focused on a single case, COHTTEC 2005, a program aimed at transforming new technologies into businesses that took place in Lisbon, Portugal, starting March 2005. In this program, participants were organized in cross-functional teams that included researchers and management students. Semi-structured interviews were made to a sample of 17 participants. These interviews were recorded and transcribed. A table was then elaborated based on the primary data provided by the subjects and these data were classified in different categories. A three-stage model of group dynamics is proposed. The major findings of this project point to the role of interpersonal relationships on group outcomes. More specifically, several patterns associated with team malfunction were uncovered, the clearest ones being autocratic decision-making and arrogant behavior from some team members, as well as escalation in relationship conflict. Implications from these results are discussed, both for future research and for practice.
Resumo:
A presente dissertação teve como finalidade estudar os testemunhos arqueológicos respeitantes às práticas funerárias levadas a cabo no atual concelho de Cascais durante os séculos VI e VII. As necrópoles em estudo são sítios bem conhecidos pelos investigadores, uma vez que a descoberta de algumas é precoce, datando de finais do século XIX. Com este trabalho, pretendeu-se introduzir uma série de componentes que a investigação privilegia atualmente, sobretudo no que respeita às vivências nos espaços rurais entre o fim do Império Romano e o domínio muçulmano na Península Ibérica. A investigação desenvolvida baseou-se no estudo preliminar das coleções osteológicas de quatro das cinco necrópoles, bem como na prospeção e no levantamento arqueológicos. O inventário antropológico teve como objetivo apurar o número mínimo de indivíduos por necrópole e por sepultura e fazer uma caracterização básica do sexo e da idade dos inumados. A prospeção assentou na análise das fontes bibliográficas sobre os sítios. Os trabalhos de campo desenvolveram-se no sentido de apurar o estado de conservação dos vestígios, na eventual identificação de outros novos e no consequente levantamento gráfico e fotográfico dos mesmos. Foi igualmente examinado o espólio cerâmico e metálico recolhido aquando da escavação das necrópoles, de modo obter uma visão abrangente sobre os rituais funerários e a estabelecer cronologias mais precisas. Embora se trate de um estudo limitado devido à inexistência de um registo mais rigoroso dos vestígios, foi possível tirar algumas conclusões e constatar alguns padrões. Os resultados possibilitaram apontar um conjunto de condições que se repetem nos locais onde estes cemitérios se implantam, percebendo dinâmicas em relação a fatores de caráter natural e de carácter antrópico. Também se apurou que existiriam diferentes formas de organizar os espaços funerários e que estes seriam constituídos por sepulturas muito diversas do ponto de vista construtivo. Além disso, começa-se a desvelar as razões para a reutilização de sepulturas para vários enterramentos e a entender a forma como as comunidades rurais conduziam os rituais funerários, ainda muito enraizados numa antiga matriz pagã.
Resumo:
We investigate the impact of cross-delisting on firms’ financial constraints and investment sensitivities. We find that firms that cross-delisted from a U.S. stock exchange face stronger post-delisting financial constraints than their cross-listed counterparts, as measured by investment-to-cash flow sensitivity. Following a delisting, the sensitivity of investment-to-cash flow increases significantly and firms also tend to save more cash out of cash flows. Moreover, this increase appears to be primarily driven by informational frictions that constrain access to external financing. We document that information asymmetry problems are stronger for firms from countries with weaker shareholders protection and for firms from less developed capital markets.
Resumo:
We investigate the long-term performance of cross-delisted firms from U.S. stock markets. Using a sample of foreign firms listed and delisted from U.S. stock exchange markets over 2000-2012, we examine the operating performance and the long-run stock returns performance of firms post-cross-delisting. Our results suggest that cross-delisted firms have less growth opportunities than matched cross-listed firms in the long run. Moreover, firms that cross-delist after the passage of Rule 12h-6 of 2007 exhibit a significant decline in operating performance. In contrast, before the adoption of the Rule 12h-6, cross-delisted firms seem to be affected by the cost of a U.S. listing in the precross -delisting period. In addition, we provide evidence that cross-delisted firms underperform their cross-listed peers; cross-delisted firms experience negative average abnormal returns, especially in the post-delisting period.
Resumo:
Special issue guest editorial, June, 2015.
Resumo:
Traffic Engineering (TE) approaches are increasingly impor- tant in network management to allow an optimized configuration and resource allocation. In link-state routing, the task of setting appropriate weights to the links is both an important and a challenging optimization task. A number of different approaches has been put forward towards this aim, including the successful use of Evolutionary Algorithms (EAs). In this context, this work addresses the evaluation of three distinct EAs, a single and two multi-objective EAs, in two tasks related to weight setting optimization towards optimal intra-domain routing, knowing the network topology and aggregated traffic demands and seeking to mini- mize network congestion. In both tasks, the optimization considers sce- narios where there is a dynamic alteration in the state of the system, in the first considering changes in the traffic demand matrices and in the latter considering the possibility of link failures. The methods will, thus, need to simultaneously optimize for both conditions, the normal and the altered one, following a preventive TE approach towards robust configurations. Since this can be formulated as a bi-objective function, the use of multi-objective EAs, such as SPEA2 and NSGA-II, came nat- urally, being those compared to a single-objective EA. The results show a remarkable behavior of NSGA-II in all proposed tasks scaling well for harder instances, and thus presenting itself as the most promising option for TE in these scenarios.
Resumo:
A measurement is presented of the tt¯ inclusive production cross section in pp collisions at a center-of-mass energy of s√=8 TeV using data collected by the ATLAS detector at the CERN Large Hadron Collider. The measurement was performed in the lepton+jets final state using a data set corresponding to an integrated luminosity of 20.3 fb−1. The cross section was obtained using a likelihood discriminant fit and b-jet identification was used to improve the signal-to-background ratio. The inclusive tt¯ production cross section was measured to be 260±1(stat)+22−23(stat)±8(lumi)±4(beam) pb assuming a top-quark mass of 172.5 GeV, in good agreement with the theoretical prediction of 253+13−15 pb. The tt¯→(e,μ)+jets production cross section in the fiducial region determined by the detector acceptance is also reported.