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Purpose: Depression in older females is a significant and growing problem. Females who experience life stressors across the life span are at higher risk for developing problems with depression than their male counterparts. The primary aim of this study was (a) to examine gender-specific differences in the correlates of depression in older primary care patients based on baseline and longitudinal analyses; and (b) to examine the longitudinal effect of biopsychosocial risk factors on depression treatment outcomes in different models of behavioral healthcare (i.e., integrated care and enhanced referral). Method: This study used a quantitative secondary data analysis with longitudinal data from the Primary Care Research in Substance Abuse and Mental Health for Elderly (PRISM-E) study. A linear mixed model approach to hierarchical linear modeling was used for analysis using baseline assessment, and follow-up from three-month and six-month. Results: For participants diagnosed with major depressive disorder female gender was associated with increased depression severity at six-month compared to males at six-month. Further, the interaction between gender and life stressors found that females who reported loss of family and friends, family issues, money issues, medical illness was related to higher depression severity compared to males whereas lack of activities was related to lower depression severity among females compared to males. Conclusion: These findings suggest that gender moderated the relationship between specific life stressors and depression severity similar to how a protective factor can impact a person’s response to a problem and reduce the negative impact of a risk factor on a problem outcome. Therefore, life stressors may be a reliable predictor of depression for both females and males in either behavioral health treatment model. This study concluded that life stressors influence males basic comfort, stability, and survival whereas life stressors influence females’ development, personal growth, and happiness; therefore, life stressors may be a useful component to include in gender-based screening and assessment tools for depression.

The problem of determining the structure of linear transformations on the algebra of n-square matrices over the complex field is discussed by M. Marcus and B. N. Moyls in the paper ''Linear Transformations on Algebras of Matrices". The authors were able to characterize linear transformations which preserve one or more of the following properties of n-square matrices; rank, determinant and eigenvalues. The problem of obtaining a similar characterization of transformations as given by M. Marcus and B. N. Moyls but for a wider class of fields is considered in this thesis. In particular, their characterization of rank preserving transformations holds for an arbitrary field. One of the results on determinant preserving transformations obtained by M. Marcus and B. N. Moyls states that if a linear transformation T maps unimodular matrices into unimodular matrices, then T preserves determinants. Since this result does not necessarily hold for algebras of matrices over finite fields, the discussion on the characterization of determinant preserving transformations is limited to algebras of matrices over infinite fields. / Science, Faculty of / Mathematics, Department of / Graduate

A generalization of a theorem of N.R. 0'Brian, zeroes of holomorphic vector fields and the Grothendieck residue, Bull. London Math. Soc, 7 (1975) is given. The theorem of Riemann-Roch and Hirzebruch for V-equivariant holomorphic vector bundles is obtained, via holomorphic vector fields, in the case all zeroes of the holomorphic vector field V are isolated. The Bruhat decomposition of G/B is obtained from the G -action on G/B . It is shown that a theorem of A. Bialynicki-Birula, Some theorems on actions of algebraic groups, Ann. of Math. 98, 480-497 (1973) is the generalization of the Bruhat decomposition on G/B , which was a conjecture of B. Iversen. The existence of a G -action on G/P with only one fixed a point is proved, where G is a connected linear algebraic group defined over an algebraically closed field k of characteristic zero and P is a parabolic subgroup of G . The following is obtained P = N[sub G](Pu) = {geG: Adg(Pu) = Pu} where G is a connected linear algebraic group, P is a parabolic subgroup of G and P^ is the tangent space of the set of unipotent elements of P at the identity. An elementary proof of P = N[sub G](P) = {geG: gPg ⁻¹=P} is given, where G is a connected linear algebraic group and P is a parabolic subgroup of G . / Science, Faculty of / Mathematics, Department of / Graduate

This dissertation applies policy improvement and successive approximation or value iteration to a general class of Markov decision processes with discounted costs. In particular, a class of Markov decision processes, called piecewise-linear, is studied. Piecewise-linear processes are characterized by the property that the value function of a process observed for one period and then terminated is piecewise-linear if the terminal reward function is piecewise-linear. Partially observable Markov decision processes have this property. It is shown that there are e-optimal piecewise-linear value functions and piecewise-constant policies which are simple. Simple means that there are only finitely many pieces, each of which is defined on a convex polyhedral set. Algorithms based on policy improvement and successive approximation are developed to compute simple approximations to an optimal policy and the optimal value function. / Business, Sauder School of / Graduate

In this thesis, I introduce a promising framework for representing an air traffic flow (stream) and flow-management action operating under weather uncertainty. I propose to use a meshed queuing and Markov-chain model---specifically, a queuing model whose service-rates are modulated by an underlying Markov chain describing weather-impact evolution---to capture traffic management in an uncertain environment. Two techniques for characterizing flow-management performance using the model are developed, namely 1) a master-Markov-chain representation technique that yields accurate results but at relatively high computational cost, and 2) a jump-linear system-based approximation that has promising scalability. The model formulation and two analysis techniques are illustrated with numerous examples. Based on this initial study, I believe that the interfaced weather-impact and traffic-flow model analyzed here holds promise to inform strategic flow contingency management in NextGen.

The purpose of this thesis is to integrate the most up-to-date information on the subject of linear programming into a comprehensive and understandable treatise for the consideration of management. The value of this study, then, is determined by the effectiveness of its presentation so that management may grasp an ample understanding of the subject.

Orientador: Concetta Kascheres / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-07-20T18:03:21Z (GMT). No. of bitstreams: 1 Figueiredo_LucianaJansendeOliveira_D.pdf: 3846694 bytes, checksum: 53880dd08682b26e037f5c580d012dc7 (MD5) Previous issue date: 1995 / Doutorado

Orientador: Marcus Vinicius Soledade Poggi de Aragão / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Ciencia da Computação / Made available in DSpace on 2018-07-20T17:26:15Z (GMT). No. of bitstreams: 1 Parreira_AndersonDelcio_M.pdf: 2926539 bytes, checksum: 1988c6c0a1469a2fe4ef22acd76a154d (MD5) Previous issue date: 1995 / Resumo: Este trabalho tem como tema central a proposta de um método de resolução eficiente do Problema de Máxima Satisfatibilidade Ponderada. Esta proposta tem sua motivação em uma classe de instâncias deste problema que pode ser resolvida em tempo polinomial. A classe de interesse neste trabalho é a das instâncias cujo grafo de co-ocorrência associado é uma k-árvore. O algoritmo capaz de resolve-lo em tempo linear é um método algébrico conhecido como Algoritmo Fundamental de Hammer, Rosenberg e Rudeanu em sua versão modificada proposta por Crama, Hansen e laumard. A abordagem deste trabalho está na utilização de métodos enumerativos, branch & bound como são mais frequentemente citados, de modo a transformar instâncias gerais em instâncias pertencentes à classe de interesse. Deste modo, tanto a enumeração como a resolução algébrica podem ter suas tarefas simplificadas. Três estratégias para esta combinação algébrico-enumerativa foram propostas e implementadas. Os algoritmos resultantes foram extensivamente testados em diferentes conjuntos de instâncias, sendo seus resultados comparados com implementações dos algoritmos puramente algébrico e puramente enumerativo. Esse trabalho apresenta também uma generalização dos limites superiores propostos por Hansen para programação não-linear 0-1 para o caso em que variáveis complementadas são incorporadas aos termos. Esses limites além de integrados ao método proposto, foram implementados e testados individualmente / Abstract: The proposal of an efficient resolution on method for the Maximum Satisfiability Problem is the object of this work. The motivation for this proposal relies on a special class of instances that can be solved by a linear time algorithm. This class is the one for which the co-occurrence graph associated to the instance is a partial k-tree. It was shown by Crama, Hansen and Jaumard how the Basic Algorithm of Hammer, Rosenberg and Rudeanu, an algebraic method, an solve these instances in linear time. The approach here proposed consists in applying an enumerative method to derive from any general instance several linear time instances that constitute a partition of the solution space. This allows the enumerative and the algebraic approaches to have their tasks simplified. Three strategies of this algebraic-enumerative combination where proposed and implemented. The resulting algorithm where tested on several different data sets. The results where compared with both algebraic and enumerative pure approaches. This work also generalizes Hansen's upper bounds and penalties for non-linear 0-1 programming to the case where complemented and uncomplement variables appear in the product terms. These where also implemented, tested and incorporated to the combined codes / Mestrado / Mestre em Ciência da Computação