On complexified analytic Hamiltonian flows and geodesics on the space of Kahler metrics

In the case of a compact real analytic symplectic manifold M we describe an approach to the complexification of Hamiltonian flows [Se, Do1, Th1] and corresponding geodesics on the space of Kahler metrics. In this approach, motivated by recent work on quantization, the complexified Hamiltonian flows act, through the Grobner theory of Lie series, on the sheaf of complex valued real analytic functions, changing the sheaves of holomorphic functions. This defines an action on the space of (equivalent) complex structures on M and also a direct action on M. This description is related to the approach of [BLU] where one has an action on a complexification M_C of M followed by projection to M. Our approach allows for the study of some Hamiltonian functions which are not real analytic. It also leads naturally to the consideration of continuous degenerations of diffeomorphisms and of Kahler structures of M. Hence, one can link continuously (geometric quantization) real, and more general non-Kahler, polarizations with Kahler polarizations. This corresponds to the extension of the geodesics to the boundary of the space of Kahler metrics. Three illustrative examples are considered. We find an explicit formula for the complex time evolution of the Kahler potential under the flow. For integral symplectic forms, this formula corresponds to the complexification of the prequantization of Hamiltonian symplectomorphisms. We verify that certain families of Kahler structures, which have been studied in geometric quantization, are geodesic families.Comment: final versio

Geometric quantization, complex structures and the coherent state transform

It is shown that the heat operator in the Hall coherent state transform for a compact Lie group $K$ is related with a Hermitian connection associated to a natural one-parameter family of complex structures on $T^*K$. The unitary parallel transport of this connection establishes the equivalence of (geometric) quantizations of $T^*K$ for different choices of complex structures within the given family. In particular, these results establish a link between coherent state transforms for Lie groups and results of Hitchin and Axelrod, Della Pietra and Witten.Comment: to appear in Journal of Functional Analysi

Effectiveness and long-term retention of anti-tumour necrosis factor treatment in juvenile and adult patients with juvenile idiopathic arthritis: data from Reuma.pt

Methods. We prospectively collected patient and disease characteristics from patients with JIA who started biological therapy. Adverse events were collected during the follow-up period. Predictors of response at 1 year and drug retention rates were assessed at 4 years of treatment for the first biologic agent.Results. A total of 812 JIA patients [65% females, mean age at JIA onset 6.9 years (s.d. 4.7)], 227 received biologic therapy; 205 patients (90.3%) were treated with an anti-TNF as the first biologic. All the parameters used to evaluate disease activity, namely number of active joints, ESR and Childhood HAQ/HAQ, decreased significantly at 6 months and 1 year of treatment. The mean reduction in Juvenile Disease Activity Score 10 (JADAS10) after 1 year of treatment was 10.4 (s.d. 7.4). According to the definition of improvement using the JADAS10 score, 83.3% respond to biologic therapy after 1 year. Fourteen patients discontinued biologic therapies due to adverse events. Retention rates were 92.9% at 1 year, 85.5% at 2 years, 78.4% at 3 years and 68.1% at 4 years of treatment. Among all JIA subtypes, only concomitant therapy with corticosteroids was found to be univariately associated with withdrawal of biologic treatment (P = 0.016).Conclusion. Biologic therapies seem effective and safe in patients with JIA. In addition, the retention rates for the first biologic agent are high throughout 4 years

Para uma semiotica literaria: Paixao, discurso, sujeito nos Trabalhos de Frei Tome de Jesus

This work alternates between description/explanation and theoretical discussion. The book itself was written from the particular perspective of the convocation/evocation of the subject, and it is in relation to this that various other questions, such as that of the 'author', of the 'text' as such, and of the 'reader', are introduced and discussed. In the second chapter I attempt to expound ideas about methods of approach-reductionism, humanism and to identify my option of an open, textualist and dialogical immanentisme. In the course of my are not only pragmatic, but are derived from the operationality of the text qua text. Chapter Three is important for its discussion of the complexity of enunciation, and of the enuntiation of the subject. The aim of this chapter is to review the notion of subject within my self-imposed limits. Chapter IV is crucial for a definition of the 'subject' as discursified passion. I show how the enunciation of the subject is linked to the process of demodalisation and reinvestment of subjectivity by means of the figures of abandonment, ascesis and mortification. It must be clearly understood that the imperious emergence of the spiritual subject implies the disappearance of the passional subject, given that the program of 'reform' implies a passage from 'flesh' to 'spirit'. The act of reading should be seen as one of the performatives of the 'subject'. In imitation of the model proposed by the narrator, the 'retreatant' learns to 'exercise' himself, abandoning the letter and discussion of the various literary genres, I believe I have shown that the Travails are not exclusively a work of parenaesis. The deciding factor in reaching this conclusion is an appeal to the text as such. Use of the concepts of direct dialogue seems to me be extremely in discussing the 'scene of enunciation', whether religious and/or mystical. The formal structure of the Travails is defined from the viewpoint of of the 'subject', of the 'instance of enunciation', of the 'illocutionary act', and the 'speech acts' on the basis of criteria which following the way of personal identification with the one to whom he, begins to hold converse. In the act of reading, and thereafter, the desire is called upon to transform itself. The Travails correspond to a moment of culture, to a moral-practical or easthetic-expressive rationality, they are not an absolute text. For the potential reader, it is question of speaking this text, of prayin. The connotation requires a construction: above all of the readerAvailable from Fundacao para a Ciencia e a Tecnologia, Servico de Informacao e Documentacao, Av. D. Carlos I, 126, 1200 Lisboa / FCT - Fundação para o Ciência e a TecnologiaSIGLEPTPortuga

Evaluation of the Earth Pressures Acting on Shafts Through Analytical and Numerical Methods

Dissertação de Mestrado Integrado em Engenharia Civil apresentada à Faculdade de Ciências e TecnologiaO uso do espaço subterrâneo em ambiente urbano é cada vez mais frequente dadas as limitações espaciais existentes à superfície, principalmente em áreas urbanas de ocupação consolidada. A utilização desse espaço é cada vez mais variada e vai desde a simples construção de caves de edifícios até à execução de colossais estações intermodais de transportes e armazéns. Com o intuito de otimizar a escavação dessas estruturas novas soluções construtivas têm sido desenvolvidas e adotadas. Uma das mais recentes técnicas utilizadas passa pela construção de poços circulares ou elípticos, onde se procura retirar o máximo partido da forma autoequilibrada destas estruturas como forma a minimizar o suporte necessário para garantir a sua estabilidade e ao mesmo tempo, assegurar um nível de deformações associadas à escavação mínimo.Para o correto dimensionamento destas estruturas é necessária uma adequada estimativa das pressões atuantes sobre o suporte e de como estas são influenciadas pelas condições geométricas do poço e pelas propriedades do solo e do suporte. Para este efeito existem na bibliografia soluções analíticas que permitem efetuar uma estimativa dessas pressões, podendo igualmente recorrer-se a modelos numéricos onde todo o comportamento do poço pode ser analisado detalhadamente.Neste trabalho são expostas as vantagens e desvantagens da construção deste tipo de estruturas e as possíveis técnicas de construção existentes no mercado. Numa segunda fase efetua-se uma revisão comparativa entre as diversas soluções analíticas existentes para o cálculo de pressões atuantes em poços de secção circular e confrontam-se os resultados obtidos com os decorrentes da realização de modelos físicos. Por último, apresenta-se a modelação numérica da escavação de um poço circular procurando-se avaliar até que ponto esta metodologia consegue capturar o comportamento observado através dos modelos físicos em diferentes condições paramétricas. Efetua-se igualmente a comparação das pressões atuantes no suporte, obtidas analiticamente e numericamente, com o intuito de avaliar a fiabilidade destas e procurar estabelecer referências que possam servir para o dimensionamento deste tipo de estruturas.The use of the subsoil in urban environment is continuously increasing due to the spatial restrictions that exist at ground-surface, and particularly in densely inhabited areas. The subsoil is nowadays used by a varied range of structures, that goes from the simple construction of cellars of buildings to the execution of colossal intermodal transport and warehouse stations. In order to optimize the excavation of these structures new design solutions have been developed and adopted. One of the most recent methods employed is the construction of circular or elliptical shafts in which the design takes full advantage of the self-balanced shape of these structures in order to minimize the support required to guarantee its stability while at the same time ensures that the excavation induces a minimum level of displacements.For the design of these structures an adequate evaluation of the pressures acting on its lining and how they are influenced by the geometrical conditions and by the soil and lining properties is required. For this purpose, there are available in the literature analytical solutions that permit to estimate the pressures, while numerical methods can also be used to analyse in detail the behaviour of the shaft.In this work the advantages and disadvantages of the construction of this type of structures and the existing construction techniques available in the market are presented. In a second stage, a comparative revision of the different analytical solutions available for the estimation of the pressure acting on circular shafts is performed, and the obtained results are compared with those obtained from physical models. Lastly, the numerical modelling of a circular shaft is carried out with the purpose of assess if this method can capture the behaviour observed in the physical models for different parametric conditions. A comparison between the pressures obtained by analytical and numerical methods is also performed aiming to attest their reliability to become references for using in the design of this type of structures

Coherent state transforms and the Mackey-Stone-Von Neumann theorem

Mackey showed that for a compact Lie group K, the pair (K, C-0(K)) has a unique non-trivial irreducible covariant pair of representations. We study the relevance of this result to the unitary equivalence of quantizations for an infinite-dimensional family of K x K invariant polarizations on T*K. The Kahler polarizations in the family are generated by (complex) time-tau Hamiltonian flows applied to the (Schrodinger) vertical real polarization. The unitary equivalence of the corresponding quantizations of T*K is then studied by considering covariant pairs of representations of K defined by geometric prequantization and of representations of C-0(K) defined via Heisenberg time-(-tau) evolution followed by time-(+tau) geometric-quantization-induced evolution. We show that in the semiclassical and large imaginary time limits, the unitary transform whose existence is guaranteed by Mackey's theorem can be approximated by composition of the time-(+tau) geometric-quantization-induced evolution with the time-(-tau) evolution associated with the momentum space [W. D. Kirwin and S. Wu, Momentum space for compact Lie groups and the Peter-Weyl theorem (unpublished)] quantization of the Hamiltonian function generating the flow. In the case of quadratic Hamiltonians, this asymptotic result is exact and unitary equivalence between quantizations is achieved by identifying the Heisenberg imaginary time evolution with heat operator evolution, in accordance with the coherent state transform of Hall. (C) 2014 AIP Publishing LLC