979 resultados para fundamental parameters
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We employ the time-dependent R-matrix (TDRM) method to calculate anisotropy parameters for positive and negative sidebands of selected harmonics generated by two-color two-photon above-threshold ionization of argon. We consider odd harmonics of an 800-nm field ranging from the 13th to 19th harmonic, overlapped by a fundamental 800-nm IR field. The anisotropy parameters obtained using the TDRM method are compared with those obtained using a second-order perturbation theory with a model potential approach and a soft photon approximation approach. Where available, a comparison is also made to published experimental results. All three theoretical approaches provide similar values for anisotropy parameters. The TDRM approach obtains values that are closest to published experimental values. At high photon energies, the differences between each of the theoretical methods become less significant.
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Background: Pedigree reconstruction using genetic analysis provides a useful means to estimate fundamental population biology parameters relating to population demography, trait heritability and individual fitness when combined with other sources of data. However, there remain limitations to pedigree reconstruction in wild populations, particularly in systems where parent-offspring relationships cannot be directly observed, there is incomplete sampling of individuals, or molecular parentage inference relies on low quality DNA from archived material. While much can still be inferred from incomplete or sparse pedigrees, it is crucial to evaluate the quality and power of available genetic information a priori to testing specific biological hypotheses. Here, we used microsatellite markers to reconstruct a multi-generation pedigree of wild Atlantic salmon (Salmo salar L.) using archived scale samples collected with a total trapping system within a river over a 10 year period. Using a simulation-based approach, we determined the optimal microsatellite marker number for accurate parentage assignment, and evaluated the power of the resulting partial pedigree to investigate important evolutionary and quantitative genetic characteristics of salmon in the system.
Results: We show that at least 20 microsatellites (ave. 12 alleles/locus) are required to maximise parentage assignment and to improve the power to estimate reproductive success and heritability in this study system. We also show that 1.5 fold differences can be detected between groups simulated to have differing reproductive success, and that it is possible to detect moderate heritability values for continuous traits (h(2) similar to 0.40) with more than 80% power when using 28 moderately to highly polymorphic markers.
Conclusion: The methodologies and work flow described provide a robust approach for evaluating archived samples for pedigree-based research, even where only a proportion of the total population is sampled. The results demonstrate the feasibility of pedigree-based studies to address challenging ecological and evolutionary questions in free-living populations, where genealogies can be traced only using molecular tools, and that significant increases in pedigree assignment power can be achieved by using higher numbers of markers.
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It has become clear over the last few years that many deterministic dynamical systems described by simple but nonlinear equations with only a few variables can behave in an irregular or random fashion. This phenomenon, commonly called deterministic chaos, is essentially due to the fact that we cannot deal with infinitely precise numbers. In these systems trajectories emerging from nearby initial conditions diverge exponentially as time evolves)and therefore)any small error in the initial measurement spreads with time considerably, leading to unpredictable and chaotic behaviour The thesis work is mainly centered on the asymptotic behaviour of nonlinear and nonintegrable dissipative dynamical systems. It is found that completely deterministic nonlinear differential equations describing such systems can exhibit random or chaotic behaviour. Theoretical studies on this chaotic behaviour can enhance our understanding of various phenomena such as turbulence, nonlinear electronic circuits, erratic behaviour of heart and brain, fundamental molecular reactions involving DNA, meteorological phenomena, fluctuations in the cost of materials and so on. Chaos is studied mainly under two different approaches - the nature of the onset of chaos and the statistical description of the chaotic state.
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Determining the morphological parameters that describe galaxies has always been a challenging task. The studies on the correlations between different photometric as well as spectroscopic parameters of the galaxies help in understanding their structure, properties of the stars and gas which constitute the galaxy, the various physical and chemical processes which determine the properties, and galaxy formation and evolution. In the last few decades, the advent of Charge Coupled Devices (CCDs) and near infrared arrays ha\·e provided quick and reliable digitized data acquisition, in the optical and near infrared bands. This has provided an avalanche of data, which can be processed using sophisticated image analysis techniques to obtain information about the morphology of galaxies. The photometric analysis performed in this thesis involve the extraction of structural parameters of early type gala.xies imaged in the near infrared K (2.2ttm) band, obtaining correlations between these, parameters and using them to constrain the large scale properties of galaxi,~s.
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The fundamental features of growth may be universal, because growth trajectories of most animals are very similar, but a unified mechanistic theory of growth remains elusive. Still needed is a synthetic explanation for how and why growth rates vary as body size changes, both within individuals over their ontogeny and between populations and species over their evolution. Here we use Bertalanffy growth equations to characterize growth of ray-finned fishes in terms of two parameters, the growth rate coefficient, K, and final body mass, m∞. We derive two alternative empirically testable hypotheses and test them by analyzing data from FishBase. Across 576 species, which vary in size at maturity by almost nine orders of magnitude, K scaled as m_∞^(-0.23). This supports our first hypothesis that growth rate scales as m_∞^(-0.25) as predicted by metabolic scaling theory; it implies that species which grow to larger mature sizes grow faster as juveniles. Within fish species, however, K scaled as m_∞^(-0.35). This supports our second hypothesis which predicts that growth rate scales as m_∞^(-0.33) when all juveniles grow at the same rate. The unexpected disparity between across- and within-species scaling challenges existing theoretical interpretations. We suggest that the similar ontogenetic programs of closely related populations constrain growth to m_∞^(-0.33) scaling, but as species diverge over evolutionary time they evolve the near-optimal m_∞^(-0.25) scaling predicted by metabolic scaling theory. Our findings have important practical implications because fish supply essential protein in human diets, and sustainable yields from wild harvests and aquaculture depend on growth rates.
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In Brazil, social rights have always been considered secondary legal categories, whose implementation could wait for the pending of political decisions. At the end of the Second World War, International Law emphasizes the protection of human beings, raising his dignity as a legal pillar of the legal orders and one of the main foundations of Constitutions. At the post-positivism Constitutionalism, the realization of social rights receives special attention with the assumption of supremacy and normativity of the Constitutions, while the judiciary participates in the realization of democracy, not only as applicator of laws, but also as the guardian of constitutionality of the acts and administrative omissions, creatively contributing to the constitutional achievement, filling gaps and normative state omissions. In this aspect, the supply of medicines, whose costs can not be supported by the individual, keep a close connection with the right to life, health and dignity of the human being, as the subject of numerous lawsuits directed against the Public Administration. Such phenomenon has caused intense debate regarding judicial activism and legitimacy of these decisions, particularly on the need to define what are the limits and possibilities considering the principle of separation of powers and the principle of reserve of the possible; bieng this the problematic developed in this research. Thus, this research aims to verify the legitimacy of judicial decisions that determines to the Public Administration the compulsory providing of medicine to those who can not afford the cost of their treatment, as well as, contribute to the dogmatic constructions of parameters to be observed by judicial interference. Regarding the methodology, this research has an investigative and descriptive caracter and an theoretical approach based on bibliographical data collection (judicial and doutrine decisions) that received qualitative treatment and dialectical approach. As a result, it is known that the judicial decision that determines the supply of medicines to those individuals who can not afford them with their own resources is legitimate and complies with the democratic principle, not violating the principle of separation of powers and the reserve of the possible, since the judicial decison is not stripped with an uniform and reasonable criteria, failing to contain high burden of subjectivism and witch signifies a possible exacerbation of functions by the judiciary, suffering, in this case, of requirement of legal certainty. It is concluded that the Court decision that determines the government the providing of medicine to those who can not afford the cost of treatment should be based on parameters such as: the protection of human dignity and the minimum existencial principle, the inafastable jurisdiction principle; compliance critique of the possible reserve principle; subsidiarity of judicial intervention; proportionality (quantitative and qualitative) in the content of the decision; the questioning about the reasons for non-delivery of the drug through administrative via; and, finally, the attention not to turn the judiciary into a mere production factor of the pharmaceutical industry, contributing to the cartelization of the right to health
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If, on one hand, only with the 1988 Federal Constitution the right to health began to receive the treatment of authentic fundamental social right; on the other, it is certain since then, the level of concretization reached as to such right depicts a mismatch between the constitutional will and the will of the rulers. That is because, despite the inherent gradualness of the process of concretization of the fundamental social rights, the Brazilian reality, marked by a picture of true chaos on public health routinely reported on the evening news, denatures the priority status constitutionally drew for the right to health, demonstrating, thus, that there is a clear deficit in this process, which must be corrected. This concern regarding the problem of the concretization of the social rights, in turn, is underlined when one speaks of the right to health, since such right, due to its intimate connection with the right to life and human dignity, ends up assuming a position of primacy among the social rights, presenting itself as an imperative right, since its perfect fruition becomes an essential condition for the potential enjoyment of the remaining social rights. From such premises, this paper aims to provide a proposal for the correction of this problem based upon the defense of an active role of the Judiciary in the concretization of the right to health as long as grounded to objective and solid parameters that come to correct, with legal certainty, the named deficit and to avoid the side effects and distortions that are currently beheld when the Judiciary intends to intervene in the matter. For that effect, emerges as flagship of this measure a proposition of an existential minimum specific to the right to health that, taking into account both the constitutionally priority points relating to this relevant right, as well as the very logic of the structuring of the Sistema Único de Saúde - SUS inserted within the core of the public health policies developed in the country, comes to contribute to a judicialization of the subject more in alignment with the ideals outlined in the 1988 Constitution. Furthermore, in the same intent to seek a concretization of the right to health in harmony with the constitutional priority inherent to this material right, the research alerts to the need to undertake a restructuring in the form of organization of the Boards of Health in order to enforce the constitutional guideline of SUS community participation, as well as the importance of establishing a new culture budget in the country, with the Constitution as a compass, pass accurately portray a special prioritization directed constitutional social rights, especially the right to health
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The school is the social place which should provide the formation of critical readers. In this context, the role of the teacher is crucial when it comes to teaching reading. Thus, this doctoral research aims to explicit the reading practices evidenced from social voices of teachers and Fundamental School students from state public schools at RN that have successful results, according to IDEB 2009. Moreover, we seek to explicit, through the positions of teachers, the conceptions of reading underlying their reading activities, as well as elucidate the social voices related to teaching of reading that are present in the National Curriculum Guide for 9 years Fundamental School and in the Political-Pedagogical Projects of the educational institutions investigated. In order to accomplish this goal, we carried out observations in the classroom, applied questionnaires with teachers and students in the 9th grade of Fundamental School, in classes of Portuguese Language, and also performed dialogical meetings with the management and pedagogics schools teams. The theoretical foundation that guides the research comes from bakhtinian thinking (2009, 2010), which addresses the dialogical perspective of language and active responsive comprehension. Furthermore, this work is anchored in theoretical reflections of Antunes (2005, 2009) and Geraldi (2003, 2006, 2010) about the reading and writing in the country, which contribute to the resizing of the teaching and learning process of Portuguese Language. This study belongs to the field of Applied Linguistics, which investigates language as social practice in the context of learning mother language or in contexts where relevant questions about the use of language are evidenced. The parameters of qualitative research in a social-historic perspective are adopted seeking to understand the school context by the subjects involved in research. The research corpus is composed of: (i) information constructed through the use of questionnaires with teachers and students; (ii) information constructed from the observed lesson and dialogue with management and pedagogical teams; (iii) a set of selected information, i.e., empiricism built through documentary analysis of the National Curriculum Guide for 9 years Fundamental School (CONSELHO NACIONAL DE EDUCAÇÃO, 2010) and the Political- Pedagogical Projects of the investigated schools. The analysis of the sayings of teachers and students suggest reading practices from various texts, in particular, from the literary sphere, in activities involving discussions, reading and reading comprehension exercises, interviews, songs, seminars organizations, concerts, dramatizations, literary weeks, among other practices. Furthermore, these analyses reveal that teach Portuguese Language requires commitment, responsibility and satisfaction, as well as more grounded theoretical principles, which make teaching practice more efficient. The research also reveals that the success of the teaching-learning process occurs by virtue of the involvement of school s segments in the educational process, creating therefore a network of responsibilities. In this sense, this research may contribute to the production of knowledge that can guide and enrich the teaching and learning of reading, envisioning a pedagogical practice constructed from the relationship with the other, i.e., from the dialogism which provides formation of young people that exercise their citizenship
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The energy efficiency of buildings should be a goal at the pre-design phase, though the importance of the design variables is often neglected even during the design process. Highlighting the relevance of these design variables, this research studies the relationships of building location variables with the electrical energy consumption of residential units. The following building design parameters are considered: orientation, story height and sky view factor (SVF). The consideration of the SVF as a location variable contributes to the originality of this research. Data of electrical energy consumption and users' profiles were collected and several variables were considered for the development of an Artificial Neural Network model. This model allows the determination of the relative importance of each variable. The results show that the apartments' orientation is the most important design variable for the energy consumption, although the story height and the sky view factor play a fundamental role in that consumption too. We pointed out that building heights above twenty-four meters do not optimize the energy efficiency of the apartments and also that an increasing SVF can influence the energy consumption of an apartment according to their orientation.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Educação para a Ciência - FC
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Pós-graduação em Educação - FCT
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Pós-graduação em Linguística e Língua Portuguesa - FCLAR