Functional and structural characterization of the RNase II-family of enzymes

Dissertation presented to obtain a Doctoral Degree in Biology by Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa

Probabilistic maintenance and optimization strategies for deteriorating civil infrastructures

In developed countries, civil infrastructures are one of the most significant investments of governments, corporations, and individuals. Among these, transportation infrastructures, including highways, bridges, airports, and ports, are of huge importance, both economical and social. Most developed countries have built a fairly complete network of highways to fit their needs. As a result, the required investment in building new highways has diminished during the last decade, and should be further reduced in the following years. On the other hand, significant structural deteriorations have been detected in transportation networks, and a huge investment is necessary to keep these infrastructures safe and serviceable. Due to the significant importance of bridges in the serviceability of highway networks, maintenance of these structures plays a major role. In this paper, recent progress in probabilistic maintenance and optimization strategies for deteriorating civil infrastructures with emphasis on bridges is summarized. A novel model including interaction between structural safety analysis,through the safety index, and visual inspections and non destructive tests, through the condition index, is presented. Single objective optimization techniques leading to maintenance strategies associated with minimum expected cumulative cost and acceptable levels of condition and safety are presented. Furthermore, multi-objective optimization is used to simultaneously consider several performance indicators such as safety, condition, and cumulative cost. Realistic examples of the application of some of these techniques and strategies are also presented.

A reliability-based measure of robustness for concrete structures subjected to corrosion

This work is a contribution to the definition and assessment of structural robustness. Special emphasis is given to reliability of reinforced concrete structures under corrosion of longitudinal reinforcement. On this communication several authors’ proposals in order to define and measure structural robustness are analyzed and discussed. The probabilistic based robustness index is defined, considering the reliability index decreasing for all possible damage levels. Damage is considered as the corrosion level of the longitudinal reinforcement in terms of rebar weight loss. Damage produces changes in both cross sectional area of rebar and bond strength. The proposed methodology is illustrated by means of an application example. In order to consider the impact of reinforcement corrosion on failure probability growth, an advanced methodology based on the strong discontinuities approach and an isotropic continuum damage model for concrete is adopted. The methodology consist on a two-step analysis: on the first step an analysis of the cross section is performed in order to capture phenomena such as expansion of the reinforcement due to the corrosion products accumulation and damage and cracking in the reinforcement surrounding concrete; on the second step a 2D deteriorated structural model is built with the results obtained on the first step of the analysis. The referred methodology combined with a Monte Carlo simulation is then used to compute the failure probability and the reliability index of the structure for different corrosion levels. Finally, structural robustness is assessed using the proposed probabilistic index.

Structural change: a brief review

This is a short summary of some aspects of structural change models, and is not intended to be comprehensive survey or review. Many important works have been left out. Also, the presentation was not intended to be rigorous nor general. It’s main purpose is only to focus on some recent developments in this area and motivate the reader to learn more.

Active bionanoconjugates of laccase and gold nanoparticles: kinetic and structural studies

Thesis for the master degree in Structural and Functional Biochemistry

Spatial and temporal analysis of recent drought using vegetation temperature condition index: case of Somali regional state of Ethiopia

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

The differential effects of switching costs and attractiveness of alternatives on customer loyalty

Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Estatística e Gestão de Informação.

An NMR structural study of nickel-substituted rubredoxin

J Biol Inorg Chem (2010) 15:409–420 DOI 10.1007/s00775-009-0613-6

Kinetic, Structural, and EPR Studies Reveal That Aldehyde Oxidoreductase from Desulfovibrio gigas Does Not Need a Sulfido Ligand for Catalysis and Give Evidence for a Direct Mo-C Interaction in a Biological System

J. Am. Chem. Soc., 2009, 131 (23), pp 7990–7998 DOI: 10.1021/ja809448r

Correlating EPR and X-ray structural analysis of arsenite-inhibited forms of aldehyde oxidoreductase

J Biol Inorg Chem (2007) 12:353–366 DOI 10.1007/s00775-006-0191-9

Structural and electron paramagnetic resonance (EPR) studies of mononuclear molybdenum enzymes from sulfate-reducing bacteria

Acc. Chem. Res., 2006, 39 (10), pp 788–796 DOI: 10.1021/ar050104k

Desulfovibrio gigas ferredoxin II: redox structural modulation of the [3Fe–4S] cluster

J Biol Inorg Chem (2006) 11: 307–315 DOI 10.1007/s00775-005-0077-2

Membrane structural changes support the involvement of mitochondria in the bile salt-induced apoptosis of rat hepatocytes

Clin Sci (Lond). 2002 Nov;103(5):475-85

Structural and functional studies of PpcA: a key protein in the electron transfer pathways of Geobacter sulfurreducens

Dissertação para obtenção do Grau de Doutor em Bioquímica, ramo de Biotecnologia

Contribuição para a adaptação cultural do Neck Disability Index e caraterização da prática de fisioterapia em pacientes com dor crónica cervical

RESUMO: Objetivo: Este trabalho teve como objetivo contribuir para o processo de adaptação cultural do Neck Disability Index (NDI), através da análise da sua unidimensionalidade e do estudo da sua fiabilidade (consistência interna e fiabilidade teste-reteste), validade de constructo e poder de resposta. De igual forma pretendeu-se caraterizar a intervenção realizada pela fisioterapia e os resultados obtidos em pacientes com Dor Cervical Crónica (DCC). Introdução: A dor cervical é um problema cada vez mais comum nos países industrializados, constituindo uma das três condições mais frequentemente reportadas por queixas de origem músculo-esquelética. A sua incidência é um fenómeno em crescimento, com custos implicados para a sociedade. Desta forma reconhece-se a importância de um instrumento que monitorize a evolução da incapacidade funcional associada à DCC. O NDI é atualmente o instrumento de avaliação mais recomendado para avaliar a incapacidade funcional associada à dor cervical. Foi traduzido e adaptado à língua portuguesa, mas à data não foi realizada nenhuma avaliação das suas propriedades psicométricas. Por outro lado, apesar de a literatura referir que os serviços de Fisioterapia são extremamente procurados por indivíduos com DCC, em Portugal, a informação sobre a sua prática nesta condição clínica é escassa ou mesmo inexistente. Assim, e sendo a incapacidade nas atividades funcionais uma das variáveis de maior impacto da DCC e ao mesmo tempo um dos resultados principais da intervenção da Fisioterapia, importa por um lado possuir instrumentos capazes de avaliar o nível de incapacidade funcional e a sua mudança, e por outro, aferir qual a intervenção realizada pela Fisioterapia e quais os resultados obtidos. Metodologia: Realizou-se um estudo de coorte prospetivo com uma amostra de conveniência, do tipo não probabilístico, constituída por 88 pacientes com DCC de origem músculo-esquelética e causa não traumática referenciados para 6 serviços de fisioterapia / medicina física e de reabilitação de clínicas e centros de reabilitação, sendo elegíveis todos os pacientes que cumprissem os critérios de inclusão e exclusão estabelecidos. Os pacientes foram avaliados em três momentos pré-definidos: antes do início das sessões de fisioterapia ou na 1ª semana de tratamento; 4 a 7 dias após a 1ª avaliação; e 7 semanas após o início da fisioterapia. Para verificação da unidimensionalidade do NDI, procedeu-se a uma Análise Fatorial Exploratória. As propriedades psicométricas do NDI avaliadas foram a Fiabilidade (consistência interna e fiabilidade teste-reteste), a Validade de Constructo e o Poder de Resposta. Posteriormente procedeu-se à caraterização da prática da fisioterapia quanto às modalidades utilizadas, número de sessões de tratamento e duração do episódio de cuidados. Adicionalmente descreveu-se os resultados obtidos após a intervenção da fisioterapia ao nível da dor e incapacidade. Resultados: os resultados obtidos foram positivos e significativos, com a confirmação da unidimensionalidade do NDI, sendo que em todos os critérios seguidos o fator mínimo retido foi de um. Na avaliação da consistência interna o valor obtido foi acima do mínimo aceitável (α Cronbach = 0,77), enquanto o valor de fiabilidade teste-reteste foi elevado (CCI =0,95). De igual forma, os resultados foram positivos para a validade de constructo, obtendo-se uma associação positiva do NDI com a Escala Numérica da dor (END). O valores de poder de resposta reportaram uma Área Abaixo da Curva de 0,63 (IC 95%=0,51-0,75), com valor de Diferença Mínima Clinicamente importante de 5,5 pontos (sensibilidade = 69,6%; especificidade = 43,6%). Relativamente á intervenção de fisioterapia em casos de DCC verificou-se que as características da prática da fisioterapia reportadas neste relatório são de difícil comparação ou análise dada a escassez ou inexistência de trabalhos publicados sobre este assunto em pacientes com DCC. No entanto, neste estudo, encontraram-se reduções significativas na intensidade da dor e incapacidade funcional após a intervenção de fisioterapia (z= -7,16; p<0,001 e t= 10,412, p<0,05, respetivamente). Conclusão: Os resultados do presente estudo revelam que o NDI-VP possui uma boa Fiabilidade, Validade de Constructo e Poder de Resposta. Revela ainda que a intervenção da fisioterapia em casos de DCC, apesar da escassez de trabalhos publicados, proporciona uma redução significativa dos níveis de dor e incapacidade em pacientes com DCC.--------------- ABSTRACT:Objective: the aim of this study was to contribute for the process of cultural adaption of the Neck Disability Index (NDI), through the analysis of his unidimensionality and the study of his reliability (internal consistency and test-retest reliability), construct validity and responsiveness. At the same time it pretends to characterize the intervention performed by physical therapy and the results in patients with Chronic Neck Pain (CNP). Introduction: neck pain is a common problem in the industrialized countries, since is one of the three most reported conditions by complaints with musculoskeletal origin. His incidence is a growth phenomena that implicate great costs to society. Therefore the importance of an instrument that monitories the evolution of the functional disability associated to CNP is recognized. Nowadays, NDI is the instrument most recommended to evaluate functional disability associated to neck pain. It has been translated and adapted to portuguese but, till now, no evaluation of his psychometric proprieties has been completed. In the other hand, despite literature refers that physical therapy services are extremely searched by patients with neck pain, in Portugal, the information about practice in this clinical condition is very few or inexistent. Therefore, and since disability in the functional activities is one of the variables with most impact of CNP and, at the same time, one of the main results of physical therapy interventions, it’s important to have instruments capable of evaluate the level of functional disability and his change, and also calculate which intervention of physical therapy is most appropriate and his results. Methodology: it was used a prospective cohort study with a convenience sample, non-probabilistic, consisting of 88 patients with CNP of musculoskeletal origin and non-traumatic cause, referred to 6 physical therapy services of clinics and rehabilitation centers, and fulfilled the inclusion and exclusion criteria established. Patients were evaluated in three pre-defined moments: before the beginning of physical therapy or during the first week of treatment; 4 to 7 days after the first evaluation; and 7 weeks after beginning of physical therapy. To verify NDI unidimensionality, we run an Exploratory Factorial Analysis. NDI psychometric proprieties evaluated were reliability (internal consistency and test-retest reliability), construct validity and responsiveness. Subsequently, it was proceeded the characterization the practice of physical therapy regarding to the modalities used, the number of treatment sessions and duration of the episode of care. Additionally it was described the results obtained after the intervention of the physical therapy, the level of pain and the disability. Results: results were positive and significant, with the confirmation of the NDI unidimensionality, since in every followed criteria the minimal retained factor was one. In the evaluation of internal consistency the value was above the minimal accepted (α Cronbach = 0,77), and the test-retest reliability value was high (CCI =0,95). Results were positive to construct validity, with an positive association of the NDI with Numeric Rating Scale (NRS). Responsiveness values reported an Area Under Curve (AUC) of 0,63 (IC 95%=0,51-0,75) with a Minimal Important Detectable Change (MIDC) of 5,5 points (sensitivity = 69,9%; specificity = 43,6%). Regarding physical therapy interventions in CNP, it was verified that the physical therapy characteristics reported are difficult to compare or analyze since there are very few published studies about this topic. However, in this study, significant reductions were founded in pain intensity and functional disability after intervention(z= -7,16; p<0,001 and t= 10,412, p<0,05, respectively).Conclusion: present study results reveals that NDI has an good reliability, construct validity and responsiveness. It also reveals that physical therapy intervention in CNP, beside few studies published, result in a significant reduction of pain and disability levels in patients with CNP.