979 resultados para TRANSFERABLE INTERACTION MODELS


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Pós-graduação em Microbiologia - IBILCE

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To interpret the mean depth of cosmic ray air shower maximum and its dispersion, we parametrize those two observables as functions of the rst two moments of the lnA distribution. We examine the goodness of this simple method through simulations of test mass distributions. The application of the parameterization to Pierre Auger Observatory data allows one to study the energy dependence of the mean lnA and of its variance under the assumption of selected hadronic interaction models. We discuss possible implications of these dependences in term of interaction models and astrophysical cosmic ray sources.

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The identification of molecular processes involved in cancer development and prognosis opened avenues for targeted therapies, which made treatment more tumor-specific and less toxic than conventional therapies. One important example is the epidermal growth factor receptor (EGFR) and EGFR-specific inhibitors (i.e. erlotinib). However, challenges such as drug resistance still remain in targeted therapies. Therefore, novel candidate compounds and new strategies are needed for improvement of therapy efficacy. Shikonin and its derivatives are cytotoxic constituents in traditional Chinese herbal medicine Zicao (Lithospermum erythrorhizin). In this study, we investigated the molecular mechanisms underlying the anti-cancer effects of shikonin and its derivatives in glioblastoma cells and leukemia cells. Most of shikonin derivatives showed strong cytotoxicity towards erlotinib-resistant glioblastoma cells, especially U87MG.ΔEGFR cells which overexpressed a deletion-activated EGFR (ΔEGFR). Moreover, shikonin and some derivatives worked synergistically with erlotinib in killing EGFR-overexpressing cells. Combination treatment with shikonin and erlotinib overcame the drug resistance of these cells to erlotinib. Western blotting analysis revealed that shikonin inhibited ΔEGFR phosphorylation and led to corresponding decreases in phosphorylation of EGFR downstream molecules. By means of Loewe additivity and Bliss independence drug interaction models, we found erlotinb and shikonin or its derivatives corporately suppressed ΔEGFR phosphorylation. We believed this to be a main mechanism responsible for their synergism in U87MG.ΔEGFR cells. In leukemia cells, which did not express EGFR, shikonin and its derivatives exhibited even greater cytotoxicity, suggesting the existence of other mechanisms. Microarray-based gene expression analysis uncovered the transcription factor c-MYC as the commonly deregulated molecule by shikonin and its derivatives. As validated by Western blotting analysis, DNA-binding assays and molecular docking, shikonin and its derivatives bound and inhibited c-MYC. Furthermore, the deregulation of ERK, JNK MAPK and AKT activity was closely associated with the reduction of c-MYC, indicating the involvement of these signaling molecules in shikonin-triggered c-MYC inactivation. In conclusion, the inhibition of EGFR signaling, synergism with erlotinib and targeting of c-MYC illustrate the multi-targeted feature of natural naphthoquinones such as shikonin and derivatives. This may open attractive possibilities for their use in a molecular targeted cancer therapy.

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We report a measurement of the νµ charged current quasi-elastic cross-sections on carbon in the T2K on-axis neutrino beam. The measured charged current quasi-elastic cross-sections on carbon at mean neutrino energies of 1.94 GeV and 0.93 GeV are (11.95 ± 0.19(stat.) +1.82−1.47(syst.)) ×10^−39 cm^2/neutron, and (10.64 ± 0.37(stat.)+2.03−1.65(syst.)) × 10^−39 cm^2/neutron, respectively. These results agree well with the predictions of neutrino interaction models. In addition, we investigated the effects of the nuclear model and the multi-nucleon interaction.

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Tree-reweighted belief propagation is a message passing method that has certain advantages compared to traditional belief propagation (BP). However, it fails to outperform BP in a consistent manner, does not lend itself well to distributed implementation, and has not been applied to distributions with higher-order interactions. We propose a method called uniformly-reweighted belief propagation that mitigates these drawbacks. After having shown in previous works that this method can substantially outperform BP in distributed inference with pairwise interaction models, in this paper we extend it to higher-order interactions and apply it to LDPC decoding, leading performance gains over BP.

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Underspanned suspension bridges are structures with important economical and aesthetic advantages, due to their high structural efficiency. However, road bridges of this typology are still uncommon because of limited knowledge about this structural system. In particular, there remains some uncertainty over the dynamic behaviour of these bridges, due to their extreme lightness. The vibrations produced by vehicles crossing the viaduct are one of the main concerns. In this work, traffic-induced dynamic effects on this kind of viaduct are addressed by means of vehicle-bridge dynamic interaction models. A finite element method is used for the structure, and multibody dynamic models for the vehicles, while interaction is represented by means of the penalty method. Road roughness is included in this model in such a way that the fact that profiles under left and right tyres are different, but not independent, is taken into account. In addition, free software {PRPgenerator) to generate these profiles is presented in this paper. The structural dynamic sensitivity of underspanned suspension bridges was found to be considerable, as well as the dynamic amplification factors and deck accelerations. It was also found that vehicle speed has a relevant influence on the results. In addition, the impact of bridge deformation on vehicle vibration was addressed, and the effect on the comfort of vehicle users was shown to be negligible.

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Geralmente, nos experimentos genótipo por ambiente (G × E) é comum observar o comportamento dos genótipos em relação a distintos atributos nos ambientes considerados. A análise deste tipo de experimentos tem sido abordada amplamente para o caso de um único atributo. Nesta tese são apresentadas algumas alternativas de análise considerando genótipos, ambientes e atributos simultaneamente. A primeira, é baseada no método de mistura de máxima verossimilhança de agrupamento - Mixclus e a análise de componentes principais de 3 modos - 3MPCA, que permitem a análise de tabelas de tripla entrada, estes dois métodos têm sido muito usados na área da psicologia e da química, mas pouco na agricultura. A segunda, é uma metodologia que combina, o modelo de efeitos aditivos com interação multiplicativa - AMMI, modelo eficiente para a análise de experimentos (G × E) com um atributo e a análise de procrustes generalizada, que permite comparar configurações de pontos e proporcionar uma medida numérica de quanto elas diferem. Finalmente, é apresentada uma alternativa para realizar imputação de dados nos experimentos (G × E), pois, uma situação muito frequente nestes experimentos, é a presença de dados faltantes. Conclui-se que as metodologias propostas constituem ferramentas úteis para a análise de experimentos (G × E) multiatributo.

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As análises biplot que utilizam os modelos de efeitos principais aditivos com inter- ação multiplicativa (AMMI) requerem matrizes de dados completas, mas, frequentemente os ensaios multiambientais apresentam dados faltantes. Nesta tese são propostas novas metodologias de imputação simples e múltipla que podem ser usadas para analisar da- dos desbalanceados em experimentos com interação genótipo por ambiente (G×E). A primeira, é uma nova extensão do método de validação cruzada por autovetor (Bro et al, 2008). A segunda, corresponde a um novo algoritmo não-paramétrico obtido por meio de modificações no método de imputação simples desenvolvido por Yan (2013). Também é incluído um estudo que considera sistemas de imputação recentemente relatados na literatura e os compara com o procedimento clássico recomendado para imputação em ensaios (G×E), ou seja, a combinação do algoritmo de Esperança-Maximização com os modelos AMMI ou EM-AMMI. Por último, são fornecidas generalizações da imputação simples descrita por Arciniegas-Alarcón et al. (2010) que mistura regressão com aproximação de posto inferior de uma matriz. Todas as metodologias têm como base a decomposição por valores singulares (DVS), portanto, são livres de pressuposições distribucionais ou estruturais. Para determinar o desempenho dos novos esquemas de imputação foram realizadas simulações baseadas em conjuntos de dados reais de diferentes espécies, com valores re- tirados aleatoriamente em diferentes porcentagens e a qualidade das imputações avaliada com distintas estatísticas. Concluiu-se que a DVS constitui uma ferramenta útil e flexível na construção de técnicas eficientes que contornem o problema de perda de informação em matrizes experimentais.

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Stroke is nowadays one of the main causes of death in Brazil and worldwide. During the rehabilitation process, patients undergo physioterapic exercises based on repetition, which may cause them to feel little progress is being made. Focusing on themes from the areas of Human-Computer Interaction and Motor Imagery, the present work describes the development of a digital game concept aimed at motor rehabilitation to the neural rehabilitation of patients who have suffered a stroke in a playful and engaging way. The research hypothesizes that an interactive digital game based on Motor Imagery contributes to patients' raised commitment in the stroke sequel rehabilitation process. The research process entailed the investigation of 10 subjects who live with sequels caused by stroke - it was further established that subjects were over 60 years old. Using as foundation an initial survey regarding target-users' specificities, where an investigation on subjectrelated aspects was carried out through Focus Group (n=9) and Contextual Analysis (n=3), having as subjects elderly individuals, a list with the necessary requirements for the conceptualization of a digital game was fleshed out. The initial survey also enabled the establishment of preliminary interactions for the formulation of game prototypes. At first, low-resolution prototypes were used, with two distinct interaction models for the game - one with a direct approach to the Motor Imagery concept, and another using a narrative with characters and scene settings. The goal was to verify participants' receptivity regarding the addition of playful activities into game dynamics. Prototypes were analyzed while being used by five patients, through the Cooperative Evaluation technique. The tests indicated a preference for option with elements in a playful narrative. Based on these results high fidelity prototypes were created, where concepts close to the game's final version were elaborated. The High Fidelity prototype was also evaluated with four patients through the Cooperative Evaluation technique. It was concluded that elderly individuals and patients were receptive to the idea of a digital game for the rehabilitation from sequels caused by stroke; that, for the success of devices aimed at these cohorts, their contexts, needs and expectations must be respected above all; and that user-centered design is an essential approach in that regard.

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Foundations support constitute one of the types of legal entities of private law forged with the purpose of supporting research projects, education and extension and institutional, scientific and technological development of Brazil. Observed as links of the relationship between company, university, and government, foundations supporting emerge in the Brazilian scene from the principle to establish an economic platform of development based on three pillars: science, technology and innovation – ST&I. In applied terms, these ones operate as tools of debureaucratisation making the management between public entities more agile, especially in the academic management in accordance with the approach of Triple Helix. From the exposed, the present study has as purpose understanding how the relation of Triple Helix intervenes in the fund-raising process of Brazilian foundations support. To understand the relations submitted, it was used the interaction models University-Company-Government recommended by Sábato and Botana (1968), the approach of the Triple Helix proposed by Etzkowitz and Leydesdorff (2000), as well as the perspective of the national innovation systems discussed by Freeman (1987, 1995), Nelson (1990, 1993) and Lundvall (1992). The research object of this study consists of 26 state foundations that support research associated with the National Council of the State Foundations of Supporting Research - CONFAP, as well as the 102 foundations in support of IES associated with the National Council of Foundations of Support for Institutions of Higher Education and Scientific and Technological Research – CONFIES, totaling 128 entities. As a research strategy, this study is considered as an applied research with a quantitative approach. Primary research data were collected using the e-mail Survey procedure. Seventy-five observations were collected, which corresponds to 58.59% of the research universe. It is considering the use of the bootstrap method in order to validate the use of the sample in the analysis of results. For data analysis, it was used descriptive statistics and multivariate data analysis techniques: the cluster analysis; the canonical correlation and the binary logistic regression. From the obtained canonical roots, the results indicated that the dependency relationship between the variables of relations (with the actors of the Triple Helix) and the financial resources invested in innovation projects is low, assuming the null hypothesis of this study, that the relations of the Triple Helix do not have interfered positively or negatively in raising funds for investments in innovation projects. On the other hand, the results obtained with the cluster analysis indicate that entities which have greater quantitative and financial amounts of projects are mostly large foundations (over 100 employees), which support up to five IES, publish management reports and use in their capital structure, greater financing of the public department. Finally, it is pertinent to note that the power of the classification of the logistic model obtained in this study showed high predictive capacity (80.0%) providing to the academic community replication in environments of similar analysis.

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We consider how three firms compete in a Salop location model and how cooperation in location choice by two of these firms affects the outcomes. We con- sider the classical case of linear transportation costs as a two-stage game in which the firms select first a location on a unit circle along which consumers are dispersed evenly, followed by the competitive selection of a price. Standard analysis restricts itself to purely competitive selection of location; instead, we focus on the situation in which two firms collectively decide about location, but price their products competitively after the location choice has been effectuated. We show that such partial coordination of location is beneficial to all firms, since it reduces the number of equilibria significantly and, thereby, the resulting coordination problem. Subsequently, we show that the case of quadratic transportation costs changes the main conclusions only marginally.

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The structure of a turbulent non-premixed flame of a biogas fuel in a hot and diluted coflow mimicking moderate and intense low dilution (MILD) combustion is studied numerically. Biogas fuel is obtained by dilution of Dutch natural gas (DNG) with CO2. The results of biogas combustion are compared with those of DNG combustion in the Delft Jet-in-Hot-Coflow (DJHC) burner. New experimental measurements of lift-off height and of velocity and temperature statistics have been made to provide a database for evaluating the capability of numerical methods in predicting the flame structure. Compared to the lift-off height of the DNG flame, addition of 30 % carbon dioxide to the fuel increases the lift-off height by less than 15 %. Numerical simulations are conducted by solving the RANS equations using Reynolds stress model (RSM) as turbulence model in combination with EDC (Eddy Dissipation Concept) and transported probability density function (PDF) as turbulence-chemistry interaction models. The DRM19 reduced mechanism is used as chemical kinetics with the EDC model. A tabulated chemistry model based on the Flamelet Generated Manifold (FGM) is adopted in the PDF method. The table describes a non-adiabatic three stream mixing problem between fuel, coflow and ambient air based on igniting counterflow diffusion flamelets. The results show that the EDC/DRM19 and PDF/FGM models predict the experimentally observed decreasing trend of lift-off height with increase of the coflow temperature. Although more detailed chemistry is used with EDC, the temperature fluctuations at the coflow inlet (approximately 100K) cannot be included resulting in a significant overprediction of the flame temperature. Only the PDF modeling results with temperature fluctuations predict the correct mean temperature profiles of the biogas case and compare well with the experimental temperature distributions.

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Chitin is an important structural component of the cellular wall of fungi and exoskeleton of many invertebrate plagues, such as insects and nematodes. In digestory systems of insects it forms a named matrix of peritrophic membrane. One of the most studied interaction models protein-carbohydrate is the model that involves chitin-binding proteins. Among the involved characterized domains already in this interaction if they detach the hevein domain (HD), from of Hevea brasiliensis (Rubber tree), the R&R consensus domain (R&R), found in cuticular proteins of insects, and the motif called in this study as conglicinin motif (CD), found in the cristallography structure of the β-conglicinin bounded with GlcNac. These three chitin-binding domains had been used to determine which of them could be involved in silico in the interaction of Canavalia ensiformis and Vigna unguiculata vicilins with chitin, as well as associate these results with the WD50 of these vicilins for Callosobruchus maculatus larvae. The technique of comparative modeling was used for construction of the model 3D of the vicilin of V. unguiculata, that was not found in the data bases. Using the ClustalW program it was gotten localization of these domains in the vicilins primary structure. The domains R&R and CD had been found with bigger homology in the vicilins primary sequences and had been target of interaction studies. Through program GRAMM models of interaction ( dockings ) of the vicilins with GlcNac had been gotten. The results had shown that, through analysis in silico, HD is not part of the vicilins structures, proving the result gotten with the alignment of the primary sequences; the R&R domain, although not to have structural similarity in the vicilins, probably it has a participation in the activity of interaction of these with GlcNac; whereas the CD domain participates directly in the interaction of the vicilins with GlcNac. These results in silico show that the amino acid number, the types and the amount of binding made for the CD motif with GlcNac seem to be directly associates to the deleterious power that these vicilins show for C. maculatus larvae. This can give an initial step in the briefing of as the vicilins interact with alive chitin in and exert its toxic power for insects that possess peritrophic membrane

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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Exatas, Departamento de Ciência da Computação, 2016.

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Operational procedures may negatively interfere in negotiation and execution regarding universities and business companies. In some cases it may even derail business interaction. Thus, aiming to overcome this and other barriers a university-industry interaction model was structured. The model enhances the appropriation of technological solutions on behalf of enterprises, as well as aim to improve the quality of teaching and research done at the university. In order to conduct a case study, sampling considering the Federal University of Rio Grande do Norte (UFRN) was made as well as the Oil and Gas sector. For data collection questionnaires, classroom observation, document analysis, semi-structured interviews were used. The study describes the companies as well as the internal organization of UFRN in their interaction context. The diagnosis related to past interactions as well as the expectations of the companies and the university s internal subjects regarding the university-industry relationship were also studied. Thus, specific questionnaires were applied for the three types of groups: researchers, managers and business companies. These subjects pointed out that the great deal of barriers they identified were related to issues regarding the university internal management. Given these barriers, the critical factors were then identified in order to overcome this reality. Among the nine critical factors only one belongs to the macro environment, while the remaining factors are related to organizational issues present in the university context. It was possible to formulate a university-business interaction model one the researched focused on the case study results and contribution from a theoretical framework that was enabled trough literature review. The model considers all business collaboration mechanisms; it focuses on a particular strategic productive sector and provides a co-evolution vision over time, according to the sector´s development strategy. The need for institutionalizing the relationship with the companies involved is pointed out. The proposed model considers all the critical factors identified by the research; it aims long-term relationship with the company and integrates teaching, research and extension actions. The model implementation was also considered. It was seen that it must be done in three phases. The phases will be defined by the level of maturity in the relationship between the university and the companies. Thus, a framework was developed in order to assess the interaction level regarding company institutionalization. Whilst structuring the model was a concern with replication came up. It was pointed out that this model should not only serve to this specific case study situation. So the final result is a model of university-industry relationship appropriate in the first instance, for UFRN, but has applicability, in general, to any Brazilian university