Development of biocompatible and “smart” porous structures using CO2-assisted processes

Dissertação apresentada para a obtenção do grau de Doutor em Engenharia Química, especialidade Engenharia da Reacção Química, pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

Evaluation of Spatial interpolation techniques for mapping climate variables with low sample density: a case study using a new gridded dataset of Bangladesh

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

Influence of the deposition pressure on the properties of transparent and conductive ZnO: Ga thin-film produced by r.f. sputtering at room temperature

Thin Solid Films, vol. 427, nº 1-2

Structured products in the current low interest rate environment

Directed Research Internship

Ecophysiology of Ruditapes decussatus

The physiological responses of the clam R. decussatus from the Ria Formosa, southern Portugal, were examined in relation to normoxia, hypoxia (11, 6, 3 and 1.2 kPa) and anoxia; acute elevation of temperature (at 20, 27 and 32 °C), and its effect on the resistance to air exposure (at 20, 28 and 35 °C); current velocity (0.6, 3, 8 17, 24 and 36 cm. s-1) and turbidity (10, 100 and 300 mg. l-1 dry weight of particulate matter), and the efficiency of this species in retaining particles of different size (at 10 and 100 mg. l-1); and to copper contamination considering both short-term acute exposure to high levels (0.1-10 mg Cu. l-1) and chronic environmental levels (0.01 mg Cu. l-1). Clearance rates, respiration rates, absorption efficiency and excretion rates were assessed through the physiological energetics in terms of the energy budget and scope for growth (SFG). Stress independent respiration rates (R) and clearance rates (CR) were observed in relation to hypoxia down to 12 kPa and 6 kPa, respectively. Anoxic rates were 3.6 % of normoxic rates. Scope for growth was greatly reduced under extreme hypoxia (14 % of SFG in normoxia). Respiration rate was temperature independent in the range 20-32 °C but the decline in clearance rate resulted in negative SFG at 32 °C. Gaping during air exposure and the maintenance of faster aerobic metabolism led to 100 % mortality in 20 hours at 35 °C, 4 days at 28 °C and 5 days at 20 °C. Low current velocities (≤ 8 cm. s-1) supported high clearance rates. Shear stresses ≥ 0.9 Pa induced sediment movement and disturbed the feeding processes resulting in decreased clearance rates (at 36 cm. s-1, is 10 % of maximum CR). The observed ability of jetting out depleted water at a different level than the one of the inhalant current results is an important adaptation of clams to the slow currents of sheltered environments. Ingestion at high seston concentrations (> 100 mg. l-1) is controled by reducing the amount filtered, lowering CR (to 30 % of CR at low seston loads) and producing pseudofeces. Observed efficient retention of particles (70-100 %) in the range 3 to 8 μm is beneficial when algal cells are diluted by fine silt particles as it is likely to occur in the clams natural environment. R. decussatus in the short term escaped the exposure to copper by valve closure and therefore acute tests are not applicable to adult clams of this species. At environmental levels chronic exposure to copper did not induce lethal effects during the exposure period (20 days), but scope for growth was reduced to c. 30 %, indicating sustained impairment of physiological functions. The sensitivity of the physiological energetics and the integrated scope for growth measurement in assessing stress effects caused by natural environmental factors was highlighted.

Analysis of glycosylation heterogeneity in antibody production by Pichia pastoris

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Biotecnologia

Influence of constraining and confinement in the molecular mobility of low molecular weight materials

Dissertation presented to obtain a Ph.D. Degree in Chemical Physics

Low-voltage low-power CMOS analogue circuits for Gaussian and uniform noise generation

IEEE International Symposium on Circuits and Systems, MAY 25-28, 2003, Bangkok, Thailand. (ISI Web of Science)

Fully transparent ZnO thin-film transistor produced at room temperature

Advanced Materials, Vol. 17, nº 5

Microeukaryoticdiversity in the extreme environments of the Iberian PyriteBelt: a comparison between universal and fungi-specific primer sets, temperature gradient gel electrophoresis and cloning

FEMS Microbiology Ecology, Vol. 57, nº 1

The role of ribonuclease R in bacterial adaptation to cold shock

RESUMO:Os microrganismos reagem à súbita descida de temperatura através de uma resposta adaptativa específica que assegura a sua sobrevivência em condições desfavoráveis. Esta adaptação inclui alterações na composição da membrana, na maquinaria de tradução e transcrição. A resposta ao choque térmico pelo frio induz uma repressão da transcrição. No entanto, a descida de temperatura induz a produção de um grupo de proteínas específicas que ajudam a ajustar/re-ajustar o metabolismo celular às novas condições ambientais. Em E. coli o processo de adaptação demora apenas quatro horas, no qual um grupo de proteínas específicas são induzidas. Depois desde período recomeça lentamente a produção de proteínas.A ribonuclease R, uma das proteínas induzidas durante o choque térmico pelo frio, é uma das principais ribonucleases em E. coli envolvidas na degradação do RNA. É uma exoribonuclease que degrada RNA de cadeia dupla, possui funções importantes na maturação e “turnover” do RNA, libertação de ribossomas e controlo de qualidade de proteínas e RNAs. O nível celular desta enzima aumenta até dez vezes após exposição ao frio e estabiliza em células na fase estacionária. A capacidade de degradar RNA de dupla cadeia é importante a baixas temperaturas quando as estruturas de RNA estão mais estáveis. No entanto, este mecanismo é desconhecido. Embora a resposta específica ao “cold shock” tenha sido descoberta há mais de duas décadas e o número de proteínas envolvidas sugerirem que esta adaptação é rápida e simples, continuamos longe de compreender este processo. No nosso trabalho pretendemos descobrir proteínas que interactuem com a RNase R em condições ambientais diferentes através do método “TAP-tag” e espectrometria de massa. A informação obtida pode ser utilizada para deduzir algumas das novas funções da RNase R durante a adaptação bacteriana ao frio e durante a fase estacionária. Mais importante ainda, RNase R poderá ser recrutada para um complexo de proteínas de elevado peso molecular durante o “cold-shock”.------------ABSTRACT:Microorganisms react to the rapid temperature downshift with a specific adaptative response that ensures their survival in unfavorable conditions. Adaptation includes changes in membrane composition, in translation and transcription machinery. Cold shock response leads to overall repression of translation. However, temperature downshift induces production of a set of specific proteins that help to tune cell metabolism and readjust it to the new environmental conditions. For Escherichia coli the adaptation process takes only about four hours with a relatively small set of specifically induced proteins involved. After this time, protein production resumes, although at a slower rate. One of the cold inducible proteins is RNase R, one of the main E. coli ribonucleases involved in RNA degradation. RNase R is an exoribonuclease that digest double stranded RNA, serves important functions in RNA maturation and turnover, release of stalled ribosomes by trans-translation, and RNA and protein quality control. The level of this enzyme increases about ten-fold after cold induction, and it is also stabilised in cells growing in stationary phase. The RNase R ability to digest structured RNA is important at low temperatures where RNA structures are stabilized but the exact role of this mechanism remains unclear. Although specific bacterial cold shock response was discovered over two decades ago and the number of proteins involved suggests that this adaptation is fast and simple, we are still far from understanding this process. In our work we aimed to discover the proteins interacting with RNase R in different environmental conditions using TAP tag method and mass spectrometry analysis. The information obtained can be used to deduce some of the new functions of RNase R during adaptation of bacteria to cold and in stationary growth phase. Most importantly RNase R can be recruited into a high molecular mass complex of protein in cold shock.

Recent droughts and the impact of North Atlantic Oscillation in Iberia; a spatiotemporal analysis based on vegetation temperature condition Index (VTCI)

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

The impact of sizeof the firm and exchange rate in the export propensity of domestic and foreign owned firms in a developing country: A study of the Brazilian exporters

A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics

Project of a bandgap voltage reference and a temperature sensor for "energy harvest" systems

Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e Computadores

Avaliação da monitorização diária da proteína C-Reativa no doente crítico

RESUMO: O objectivo desta Tese de Doutoramento foi estudar o valor da Proteína CReactiva(PCR) como marcador de infecção e sepsis. Por definição, um marcador da infecção não está presente se o doente não está infectado, deve aparecer concomitantemente ou idealmente preceder a instalação da infecção, deve desaparecer com a instituição de terapêutica antimicrobiana adequada e permanecer elevado se a infecção for refractária ao tratamento. Do ponto de vista biológico, a PCR é o protótipo das proteínas de fase aguda, com uma marcada elevação da sua concentração sérica em resposta a diversos estímulos inflamatórios em particular infecções bacterianas. A sua concentração sérica depende apenas da intensidade do estímulo e da velocidade de síntese hepática, não sendo influenciada por nenhum factor ou tratamento a não ser que este tenha influência directa sobre o estímulo desencadeante, o que a torna um marcador de infecção com grande potencial. Nesta Tese comparou-se a PCR com marcadores clássicos de infecção, temperatura e contagem leucocitária, em diversas situações clínicas analisando doentes com infecções documentadas e doentes controlos, sem infecção. Globalmente os resultados dos trabalhos desta Tese mostram que a PCR é um bom marcador de infecção de acordo com a definição previamente apresentada. Em conjunto com a restante avaliação clínica e laboratorial, a monitorização diária da PCR nos doentes sem infecção mostrou ser útil como sentinela da infecção, isto é, apresenta valores baixos nos doentes sem infecção e sobe precocemente nos doentes que desenvolvem uma infecção. Nos doentes com infecção documentada revelou um ser bom marcador de resposta à terapêutica e evolução clínica, diminuindo naqueles que melhoravam e persistindo elevada nos que tinham mau prognóstico, bem assim como identificar diferentes perfis evolutivos. Em suma, a monitorização diária da PCR mostrou utilidade ao longo de todo o internamento na Unidade de Cuidados Intensivos, quer na presença quer na ausência de infecção. Deste todo, a monitorização diária da PCR pode a possibilitar uma utilização mais racional e judiciosa da terapêutica antimicrobiana, contribuindo dessa forma para uma diminuição da toxicidade e da pressão antibiótica, menor risco de emergência de resistências e finalmente diminuição dos custos. Uma vez que, os doentes internados nas Unidades de Cuidados Intensivos apresentam as mesmas doenças que os restantes doentes admitidos no hospital apenas se distinguindo pela sua maior gravidade, poder-se-á extrapolar que a PCR também é potencialmente um bom marcador de infecção nestes doentes. ----------------ABSTRACT: The aim of this PhD Thesis was to assess the value of C-Reactive Protein (CRP) as a marker of infection and sepsis. A marker of infection should be absent in a non-infected patient, should increase alongside or ideally precede the development of an infection, and finally should assess the therapeutic response, that is to say decrease or even disappear with adequate antimicrobial therapy or on the opposite remain elevated if the infection is refractory to the prescribed treatment. The biology of CRP makes it the prototype of acute phase proteins, with marked and sharp elevations of its serum concentration in response to several inflammatory stimulus in particular bacterial infections. Besides, CRP level depends only of the intensity of the stimulus and the rate of hepatic synthesis. Its concentration is not modified by any therapy or intervention. Only those interventions affecting the inflammatory process responsible for the acute phase reaction can change the CRP level. These properties make CRP a potentially good marker of infection. In this Thesis the value of CRP was studied in comparison to traditional markers of infection, like temperature and white cell count, in different clinical situations analysing patients with documented infections and a control group without infection. The aggregated results of the analysis presented in this Thesis illustrate that CRP could be used as a marker of infection. In conjunction with other clinical and laboratory manifestations of sepsis, daily CRP measurement in patients without infection was useful in prediction of infection as its concentration remains low in patients without infection whereas if an infection appears its levels raise markedly. In addition, in patients with documented infections CRP was useful as a marker of therapeutic response and follow-up, with marked decreases in patients with good outcome and remaining elevated in those with poor prognosis, as well as the recognition of different patterns of evolution. In summary, daily CRP measurement was helpful in critical ill patients along the entire Intensive Care Unit stay, both in the presence and in the absence of infection. As a result, daily CRP measurement can assure a better and more rational use of antibiotics and consequently contribute to a decrease in the antibiotic toxicity and demand, reducing the risks of emergence of resistant strains aas well as costs. Provided that patients admitted to an Intensive Care Unit presented the same clinical diagnosis as those admitted to the wards but with higher severity, one can speculate that CRP is also a potentially good marker of infection in these of patients.