Popular beliefs regarding the treatment of senile cataract

OBJECTIVE: To identify popular beliefs regarding the treatment of senile cataract in patients enrolled in the community health programs on eye rehabilitation. METHODS: A cross-sectional survey was carried out using an interview questionnaire that was applied to 776 subjects drawn from a non-probabilistic sample in five cities of the state of São Paulo. The sample was made up of 47.2% males and 52.8% females, aged 50 to 96 years (average age 71.6 years). RESULTS: Of the total of subjects studied, 41.9% had never attended school, and 78.5% were no longer in the employment market. Most (85.1%) credited the sight restoration to cataract surgery. Among those unconvinced, 47.4% asserted that sight restoration depended only on God's will. A greater proportion of women than men (p 0.0000) believed in the association of cataract and menopause, maternity, and menstrual periods and they admitted using herbal and rose teas for treating cataract. CONCLUSIONS: Misbeliefs related to the causes and treatment of senile cataract were identified, most probably of sociocultural basis, indicating the need of education on the subject.

Valor preditivo de exames pré-operatórios em facectomias

OBJETIVO: Determinar a prevalência de resultados anormais numa rotina de exames pré-operatórios para facectomias e sua influência na ocorrência de complicações clínicas perioperatórias. MÉTODOS: Estudo prospectivo desenvolvido em um centro médico acadêmico no Brasil, com uma amostra de 746 pacientes, selecionados entre indicados para cirurgia de catarata. Para todos os pacientes foram solicitados eletrocardiograma, hemograma completo e glicemia de jejum, além de uma avaliação clínica. Foram excluídos do estudo pacientes com menos de 40 anos de idade, pacientes submetidos previamente à cirurgia ocular, pacientes com indicação de anestesia geral, ou pacientes que sofreram infarto agudo do miocárdio até três meses antes da cirurgia. Eventos médicos intra-operatórios foram registrados numa ficha de protocolo. Para análise, utilizou-se do teste de Fisher e análise de variância (ANOVA). RESULTADOS: Na amostra de 746 pacientes, 405 (54,3%) eram homens. A idade média foi de 66,6±11,6 anos. Ocorreram complicações intra-operatórias em 71 (9,5%) pacientes. Houve resultados anormais em 13,5% (101 pacientes) das dosagens de hemoglobina e em 16,6% (124) das dosagens de glicemia de jejum. Em relação aos eletrocardiogramas, foram constatadas anormalidades em 46,6% (348) dos indivíduos. Houve maior prevalência de eletrocardiogramas com anormalidades em pacientes com complicações clínicas perioperatórias (p=0,02). Não existiu diferença estatisticamente significativa nas dosagens de hemoglobina (14,0±1,6 g/dL em pacientes sem complicações intra-operatórias e 14,3±1,3 g/dL em pacientes com complicações - p=0,150) e nas de glicemia de jejum (104±29 mg/dL em pacientes sem complicações e 105±41 mg/dL em pacientes com complicações - p=0,850). CONCLUSÕES: Dentro da rotina investigada de exames pré-operatórios para facectomia, apenas os resultados anormais presentes no eletrocardiograma estiveram associados à ocorrência de complicações durante o período de perioperatório.

Dynamic artificial neural network for electricity market prices forecast

This paper presents an artificial neural network applied to the forecasting of electricity market prices, with the special feature of being dynamic. The dynamism is verified at two different levels. The first level is characterized as a re-training of the network in every iteration, so that the artificial neural network can able to consider the most recent data at all times, and constantly adapt itself to the most recent happenings. The second level considers the adaptation of the neural network’s execution time depending on the circumstances of its use. The execution time adaptation is performed through the automatic adjustment of the amount of data considered for training the network. This is an advantageous and indispensable feature for this neural network’s integration in ALBidS (Adaptive Learning strategic Bidding System), a multi-agent system that has the purpose of providing decision support to the market negotiating players of MASCEM (Multi-Agent Simulator of Competitive Electricity Markets).

Symbolic Knowledge Extraction from Trained Neural Networks Governed by Lukasiewicz Logics

This work describes a methodology to extract symbolic rules from trained neural networks. In our approach, patterns on the network are codified using formulas on a Lukasiewicz logic. For this we take advantage of the fact that every connective in this multi-valued logic can be evaluated by a neuron in an artificial network having, by activation function the identity truncated to zero and one. This fact simplifies symbolic rule extraction and allows the easy injection of formulas into a network architecture. We trained this type of neural network using a back-propagation algorithm based on Levenderg-Marquardt algorithm, where in each learning iteration, we restricted the knowledge dissemination in the network structure. This makes the descriptive power of produced neural networks similar to the descriptive power of Lukasiewicz logic language, minimizing the information loss on the translation between connectionist and symbolic structures. To avoid redundance on the generated network, the method simplifies them in a pruning phase, using the "Optimal Brain Surgeon" algorithm. We tested this method on the task of finding the formula used on the generation of a given truth table. For real data tests, we selected the Mushrooms data set, available on the UCI Machine Learning Repository.

Quase-verdade e pragmatismo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Tópicos da teoria da relatividade

Dissertação de Mestrado, Matemática para Professores, 25 de Outubro 2013, Universidade dos Açores.

Inexact restoration approaches to solve mathematical program with complementarity constraints

Mathematical Program with Complementarity Constraints (MPCC) finds applica- tion in many fields. As the complementarity constraints fail the standard Linear In- dependence Constraint Qualification (LICQ) or the Mangasarian-Fromovitz constraint qualification (MFCQ), at any feasible point, the nonlinear programming theory may not be directly applied to MPCC. However, the MPCC can be reformulated as NLP problem and solved by nonlinear programming techniques. One of them, the Inexact Restoration (IR) approach, performs two independent phases in each iteration - the feasibility and the optimality phases. This work presents two versions of an IR algorithm to solve MPCC. In the feasibility phase two strategies were implemented, depending on the constraints features. One gives more importance to the complementarity constraints, while the other considers the priority of equality and inequality constraints neglecting the complementarity ones. The optimality phase uses the same approach for both algorithm versions. The algorithms were implemented in MATLAB and the test problems are from MACMPEC collection.

Derivative-free nonlinear optimization filter simplex

The filter method is a technique for solving nonlinear programming problems. The filter algorithm has two phases in each iteration. The first one reduces a measure of infeasibility, while in the second the objective function value is reduced. In real optimization problems, usually the objective function is not differentiable or its derivatives are unknown. In these cases it becomes essential to use optimization methods where the calculation of the derivatives or the verification of their existence is not necessary: direct search methods or derivative-free methods are examples of such techniques. In this work we present a new direct search method, based on simplex methods, for general constrained optimization that combines the features of simplex and filter methods. This method neither computes nor approximates derivatives, penalty constants or Lagrange multipliers.

Harvesting dynamic aspects from a real rational map : the bulb of period 5

This journal provides immediate open access to its content on the principle that making research freely available to the public supports a greater global exchange of knowledge.

Coletores de distribuição e sua otimização hidráulica, aplicados a uma instalação de produção de água arrefecida em sistemas de AVAC ( Fórum Picoas)

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Mecânica

Desenvolvimento e estudo de modelos de FACTS para o trânsito de energia: aplicação ao estudo das condições técnicas de ligação de linhas MAT

Dissertação para obtenção do grau de Mestre em Engenharia Electrotécnica Ramo de Energia

Mapping stability : real rational maps of degree zero

In memory of our beloved Professor José Rodrigues Santos de Sousa Ramos (1948-2007), who João Cabral, one of the authors of this paper, had the honor of being his student between 2000 and 2006, we wrote this paper following the research by experimentation, using the new technologies to capture a new insight about a problem, as him so much love to do it. His passion was to create new relations between different fields of mathematics. He was a builder of bridges of knowledge, encouraging the birth of new ways to understand this science. One of the areas that Sousa Ramos researched was the iteration of maps and the description of its behavior, using the symbolic dynamics. So, in this issue of this journal, honoring his memory, we use experimental results to find some stable regions of a specific family of real rational maps, the ones that he worked with João Cabral. In this paper we describe a parameter space (a,b) to the real rational maps fa,b(x) = (x2 −a)/(x2 −b), using some tools of dynamical systems, as the study of the critical point orbit and Lyapunov exponents. We give some results regarding the stability of these family of maps when we iterate it, specially the ones connected to the order 3 of iteration. We hope that our results would help to understand better the behavior of these maps, preparing the ground to a more efficient use of the Kneading Theory on these family of maps, using symbolic dynamics.

Estudo comparativo das técnicas, parâmetros e indicadores de avaliação da qualidade do leite dos Açores

Dissertação de Mestrado, Tecnologia e Segurança Alimentar, 27 de Novembro de 2015, Universidade dos Açores.

The 27th British liquid crystal society annual meeting 2013, Cambridge

Attending the British Liquid Crystal Society’s (BLCS) Annual Meeting was a formative experience in my days as a PhD student, starting way back in the 1990s. At that time, this involved travelling to (to me) exotic parts of the United Kingdom, such as Reading, Oxford or Manchester, away from Southampton where I was based. Some postdoctoral years in a different country followed, and three BLCS Meetings were missed, until in 1997 and 1998, I was able to attend again, in Southampton and Leeds, respectively. Not much had changed from my student days, the size and the format were still about the same, many of the leading characters were still around, and the closing talk would still be given by John Lydon. Well, at some point, I got myself a proper academic job on the Continent and stopped attending BLCS Annual Meetings altogether. The fond memories of my youth started to fade. Were the Meetings still on? It seemed so, as old friends and acquaintances would occasionally recount attending them, and even winning prizes at them. But, it all seemed rather remote now. Until, that is, it came to pass that the 27th BLCS Meeting would be held in Selwyn College, Cambridge, just down (or up, depending on how you look at it) the road from the Isaac Newton Institute, where I was spending part of my sabbatical leave. The opportunity to resume attendance could not be missed. A brief e-mail exchange with the organisers, and a cheque to cover the fee, duly secured this. And thus, it was with trepidation that I approached my first BLCS Annual Meeting in more than a decade.

Custo social de duas técnicas de cirurgia de catarata no Brasil

OBJETIVO: Comparar os custos sociais pós-operatórios da cirurgia de catarata segundo as técnicas de facoemulsificação (Faco) e extração extracapsular (EECP). MÉTODOS: Estudo prospectivo, intervencionista e randomizado com 205 pacientes: 101 submetidos à Faco e 104 à EECP, no sistema público em São Paulo, SP, em 2002. Para avaliação do impacto socioeconômico dessas cirurgias, foi considerado o custo no período pós-operatório para os pacientes, empregadores e Sistema Previdenciário. As comparações entre os grupos foram feitas pelo teste do qui-quadrado ou por Mann-Whitman, quando apropriado. O nível de significância estabelecido foi de 5%. RESULTADOS: Considerando os gastos com os retornos hospitalares e aquisição de lentes corretivas (óculos), o paciente submetido à Faco obteve uma economia média de US$ 16,74, comparado ao paciente submetido à EECP. Quanto aos custos com licença médica, na primeira quinzena de afastamento do paciente, e os gastos com a ausência no trabalho do acompanhante, nos retornos pós-operatórios, o sistema empresarial obteve uma economia média de US$ 0,18 no grupo dos pacientes submetidos à Faco em relação ao grupo submetido à EECP. O gasto do Sistema Previdenciário por paciente foi estimado em US$ 6,57 no grupo Faco e US$ 51,15 no grupo EECP. CONCLUSÕES: A técnica de Faco representou economia média de US$ 61,5 para empregadores, pacientes, acompanhantes e Sistema Previdenciário, quando comparada à técnica de EECP.