4,074 research outputs found
Quantum Griffiths effects in metallic systems
No full textWe show that two apparently contradictory theories on the
existence of Griffiths-McCoy singularities in magnetic metallic
systems (see Castro Neto A. H. and Jones B. A.,
Phys. Rev. B 62 (2000) 14975 and Millis A. J.,
Morr D. and Schmalian J., Phys. Rev.
B 66 (2002) 174433) are in fact mathematically equivalent. We
discuss the generic phase diagram of the problem and show that
there is a non-universal crossover temperature range
where power law behavior (Griffiths-McCoy
behavior) is expected. For power law behavior ceases to
exist due to the destruction of quantum effects generated by the
dissipation in the metallic environment. We show that T* is an
analogue of the Kondo temperature and is controlled by
non-universal couplings
A sinfonia do sagrado em Castro Alves: (Deus, Eros e mãe em Os escravos)
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Programa de Pós-Graduação em Literatura.No presente trabalho realiza-se uma leitura intertextual entre a Bíblia e Os escravos, coletânea de poemas de teor abolicionista do poeta romântico Antônio Frederico de Castro Alves (1847-1871), objetivando demonstrar que os textos poéticos arquitetam-se na desconstrução e reconstrução dos textos bíblicos. A leitura dos poemas centra-se nos personagens: Deus, Eros e Mãe, os quais conformam uma trindade poética/sagrada. A pesquisa divide-se em três movimentos: Prelúdios do sagrado no Romantismo, Tríade melódica e À guisa de coda: trindade poética. No primeiro efetuam-se algumas aproximações ao conceito do sagrado e aos Romantismos francês e brasileiro. O seguinte corresponde à leitura das composições, através das linhas melódicas: A dualidade de Deus, A ambivalência de Eros e O duplo calvário da Mãe escrava. E no último movimento amalgamam-se as inter-relações entre a trindade cristã e poética e os dramas bíblico e poético
A Business Performance Management Framework
No full textPereira, A. C. B., & de Castro Neto, M. (2020). A Business Performance Management Framework. In Á. Rocha, H. Adeli, L. P. Reis, S. Costanzo, I. Orovic, & F. Moreira (Eds.), Trends and Innovations in Information Systems and Technologies: WorldCIST 2020 (Vol. 1, pp. 312-323). (Advances in Intelligent Systems and Computing; Vol. 1159 AISC). Springer. https://doi.org/10.1007/978-3-030-45688-7_32In an increasingly competitive market, companies need to look not only at results, but also at how they can improve their performance to achieve them. Knowing the factors that influence business performance allows to identify initiatives that lead to their improvement or mitigate potential risks, ensuring strategic alignment across the organization. This article presents a Business Performance Management (BPM) framework, where the key components that impact business performance are described, which includes Business Intelligence (BI) as an integral part of the technological framework and a Performance Management (PM) cycle as a methodological approach to its implementation for business performance improvement.authorsversionpublishe
Bosonization Of A 2d Electron Gas In A Magnetic Field
No full textStarting from a Landau level description of a 2D fermion gas subject to a perpendicular uniform magnetic field, under the condition that there is a large integer number of filled Landau levels, we introduce a bosonization scheme for the low energy excitations of the system. We give an explicit construction of the fermion operator in terms of the bosons and show that the description of the elementary neutral excitations within a bosonic language provides a quadratic bosonic Hamiltonian for the interacting electron system which can be easily diagonalized. © Springer-Verlag 1997.1032279281MacDonald, A.H., (1989) The Quantum Hall Effect: A Perspective, , Dordrecht: Kluwer Academic(1990) The Quantum Hall Effect, 2nd Ed., , R.E. Prange, S.M. Girvin eds., New York: SpringerKarlhede, A., Kivelson, S.A., Sondhi, S.L., The Quantum Hall Effect: The article (1992) 9th Jerusalem Winter School on Theor. Phys., , Lectures presKallin, C., Halperin, B.I., (1984) Phys. Rev. B, 30, p. 5655Tomonaga, S., (1950) Prog. Theor. Phys. (Kyoto), 5, p. 544Pegg, D.T., Barnet, S.M., (1988) Europhysics Letters, 6, p. 483Susskind, L., Glogower, J., (1964) Physics, 1, p. 49Thirring, W., (1958) Ann. Phys. (N. Y.), 3, p. 91Luttinger, J.M., (1963) J. Math. Phys., 4, p. 1154Mattis, D., Lieb, E., (1965) J. Math. Phys., 6, p. 304Luther, A., (1975) Phys. Rev. B, 14, p. 2153Coleman, S., (1975) Phys. Rev. D., 11, p. 2088Haldane, F.D.M., (1981) J. Phys. C, 14, p. 2585H. Westfahl Jr., A.H. Castro Neto, A.O. Caldeira, cond-mat/9611004Mandelstam, S., (1975) Phys. Rev. D, 11, p. 3026Castro Neto, A.H., Fradkin, E., (1993) Phys. Rev. Lett., 72, p. 1393(1995) Phys. Rev. B, 51, p. 4048Lopez, A., Fradkin, E., (1991) Phys. Rev. B, 44, p. 5246(1992) Phys. Rev. Lett., 69, p. 2126(1993) Nucl. Phys. B, 33 C, p. 67Luther, A., (1979) Phys. Rev. B, 19, p. 320Haldane, F.D.M., Varenna Lectures (1992) (1992) Helv. Phys. Acta., 65, p. 152Houghton, A., Marston, B., (1993) Phys. Rev. B, 48, p. 7790Kwon, H.J., Houghton, A., Marston, B., (1995) Phys. Rev. B, 52, p. 800
Laboratory Biomarkers for Diagnosis and Prognosis in COVID-19
No full textSevere acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) causes a wide spectrum of clinical manifestations, with progression to multiorgan failure in the most severe cases. Several biomarkers can be altered in coronavirus disease 2019 (COVID-19), and they can be associated with diagnosis, prognosis, and outcomes. The most used biomarkers in COVID-19 include several proinflammatory cytokines, neuron-specific enolase (NSE), lactate dehydrogenase (LDH), aspartate transaminase (AST), neutrophil count, neutrophils-to-lymphocytes ratio, troponins, creatine kinase (MB), myoglobin, D-dimer, brain natriuretic peptide (BNP), and its N-terminal pro-hormone (NT-proBNP). Some of these biomarkers can be readily used to predict disease severity, hospitalization, intensive care unit (ICU) admission, and mortality, while others, such as metabolomic and proteomic analysis, have not yet translated to clinical practice. This narrative review aims to identify laboratory biomarkers that have shown significant diagnostic and prognostic value for risk stratification in COVID-19 and discuss the possible clinical application of novel analytic strategies, like metabolomics and proteomics. Future research should focus on identifying a limited but essential number of laboratory biomarkers to easily predict prognosis and outcome in severe COVID-19
Mobility of Bloch walls via the collective coordinate method
No full textWe have studied the problem of the dissipative motion of Bloch walls considering a totally anisotropic one-dimensional spin chain in the presence of a magnetic field. Using the so-called “collective coordinate method” we construct an effective Hamiltonian for the Bloch wall coupled to the magnetic excitations of the system. It allows us to analyze the Brownian motion of the wall in terms of the reflection coefficient of the effective potential felt by the excitations due to the existence of the wall. We find that for finite values of the external field the wall mobility is also finite. The spectrum of the potential at large fields is investigated and the dependence of the damping constant on temperature is evaluated. As a result we find the temperature and magnetic-field dependence of the wall mobility. © 2000 The American Physical Society.Fil: Desposito, Marcelo Arnaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Villares Ferrer, A.. Universidade Estadual de Campinas; BrasilFil: Caldeira, A. O.. Universidade Estadual de Campinas; BrasilFil: Castro Neto, A. H.. University of California; Estados Unido
Computational methods for 2D materials modelling
No full textMaterials with thickness ranging from a few nanometers to a single atomic layer present unprecedented opportunities to investigate new phases of matter constrained to the two-dimensional plane. Particle-particle Coulomb interaction is dramatically affected and shaped by the dimensionality reduction, driving well-established solid state theoretical approaches to their limit of applicability. Methodological developments in theoretical modelling and computational algorithms, in close interaction with experiments, led to the discovery of the extraordinary properties of two-dimensional materials, such as high carrier mobility, Dirac cone dispersion and bright exciton luminescence, and inspired new device design paradigms. This review aims to describe the computational techniques used to simulate and predict the optical, electronic and mechanical properties of two-dimensional materials, and to interpret experimental observations. In particular, we discuss in detail the particular challenges arising in the simulation of two-dimensional constrained fermions and quasiparticles, and we offer our perspective on the future directions in this field
Grain yield of maize as a consequence of a crop rotation with a second crop, forage, green manure and lie fallow.
No full textAmong the numerous benefits of Crop-Livestock-Forest Integration are: the restoration of soil fertility, the establishment of pastures with low costs, the improvement in physical, chemical and biological properties of the soil, the control of pests, pathogens and weeds, the recycling of nutrients from the soil, the increase in grain yield. The Crop-Livestock-Forest systems can increase job opportunities, the efficiency in the use of machinery, equipment and manpower, and also productivity and profitability. Quantify these benefits should be role of the research to support public policy actions
Adaptools 2.0: Implementation And Utilization Aspects [adaptools 2.0: Aspectos De Implementação E Utilização]
No full textThis paper present the new version of the tool AdapTools. This application provides mechanisms for implementation, execution and debugging of adaptive robots. We will focus on the aspects of implementation of the new structure of data and the model of non-deterministic execution, the new model of coding using the compiler AdapMap and improvement in the insertion of semantic routines, which makes it unnecessary to recompile the code of the tool.57527532Pistori, H., Neto, J.J., (2003) AdapTools: Aspectos de Implementação e Utilizaç ão, , Boletim técnico PCS - USPPistori, H., Neto, J.J., Costa, E.R., A free software for the development of adaptive automata (2003) IV International Forum on Free Software, 2Pistori, H., Neto, J.J., A free software for the development of adaptive automata Proceedings of the IV Workshop on Free Software - WSL (IV International Forum on Free Software), Porto Alegre, Brazil, June 5-7, 2003Neto, J., Moraes, M., Using adaptive formalisms to describe contextdependencies in natural language (2003) Lecture Notes in Artificial Intelligence, 2721, pp. 94-97. , N.J. Mamede, J. Baptista, I. Trancoso, M. das Graças, V. Nunes (Eds.): Computational Processing of the Portuguese Language 6th International Workshop, PROPOR 2003, JunePistori, H., (2003) Tecnologia Adaptativa Em Engenharia de Computação: Estado Da Arte e Aplicações, , Ph.D. dissertation, Universidade de São Paulo, São Paulo, BrasilNeto, J.J., (2004) Tecnologia Adaptativa, , (unpublished) São Paulo, Brasil, setembro deSantos, D.G., Pistori, H., Castro Jr., A.A., Neto, J.J., Adaptools: Umambiente gráfico de apoio ao desenvolvimento de software adaptativo SIMS - Simpósio de Informática e Mostra de Software Acadêmico, 2005Santos, D.G., Jesus, L., Aspectos de projeto e implementação do não- determinismo no AdapTools e seus impactos no aperfeiçoamento da ferramenta (2006) Monografia de Conclusão de Curso de Engenharia de Computação, , Campo Grande - MS, Brasil, dezembro de UCD
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