Distributed processing of large remote sensing images using MapReduce - A case of Edge Detection

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

Valorização das águas corticeiras: extracção de antioxidantes

Dissertação para obtenção do Grau de Mestre em Engenharia Química e Bioquímica

Pre-treatment of different types of lignocellulosic biomass using ionic liquids

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

Ionic liquids as catalysts of lignocellulosic biomass processing

The present work is devoted to study the pre-treatment of lignocellulosic biomass, especially wheat straw, by the application of the acidic ionic liquid (IL) such as 1-butyl-3-methylimidazolium hydrogen sulphate. The ability of this IL to hydrolysis and conversion of biomass was scrutinised. The pre-treatment with hydrogen sulphate-based IL allowed to obtain a liquor rich in hemicellulosic sugars, furans and organic acids, and a solid fraction mainly constituted by cellulose and lignin. Quantitative and qualitative analyses of the produced liquors were made by capillary electrophoresis and high-performance liquid chromatography. Pre-treatment conditions were set to produce xylose or furfural. Specific range of temperatures from 70 to 175 °C and residence times from 20.0 to 163.3 min were studied by fixing parameters such as biomass/IL ratio (10 % (w/w)) and water content (1.25 % (w/w)) in the pre-treatment process. Statistical modelling was applied to maximise the xylose and furfural concentrations. For the purpose of reaction condition comparison the severity factor for studied ionic liquid was proposed and applied in this work. Optimum conditions for xylose production were identified to be at 125 °C and 82.1 min, at which 16.7 % (w/w) xylose yield was attained. Furfural was preferably formed at higher pre-treatment temperatures and longer reaction time (161 °C and 104.5 min) reaching 30.7 % (w/w) maximum yield. The influence of water content on the optimum xylose formation was also studied. Pre-treatments with 5 and 10 % (w/w) water content were performed and an increase of 100 % and 140 % of xylose yield was observed, respectively, while the conversion into furfural maintained unchanged.

Development of new membranes based on ionic liquid materials for gas separation

In the field of energy, natural gas is an essential bridge to a clean, low carbon, renewable energy era. However, natural gas processing and transportation regulation require the removal of contaminant compounds such as carbon dioxide (CO2). Regarding clean air, the increasing atmospheric concentrations of greenhouse gases, specifically CO2, is of particular concern. Therefore, new costeffective, high performance technologies for carbon capture have been researched and the design of materials with the ability to efficiently separate CO2 from other gases is of vital importance.(...)

Managing talent through developmental job experiences (DJE): The mediating role of DJE between HPWS and employees' outcomes

In the competitive landscape of the 21st century, effectively managing human capital in firms is considered to be a potential source of sustainable performance. Therefore, in this study, we tested the influence of high-performance work systems, as a talent management tool, on employees’ experience of developmental jobs. Then, we tested the mediating effect of such experiences on employees’ engagement, exhaustion, performance and turnover intention. With a sample of 254 employees of a diversity of companies and sectors of activity, our findings demonstrated that high-performance practices increase engagement, via the promotion of developmental experiences of fit, which improves performance and decreases turnover intention. Besides, those practices do not control for the pressure dimension of the developmental job experiences that increases exhaustion and turnover intention despite not worsening performance.

Design and characterization of novel biopolymeric structure using biocompatible ionic liquids

The main objective of this thesis was the development of polymeric structures from the dissolution of FucoPol, a bacterial exopolysaccharide (EPS), in a biocompatible ionic liquid, choline acetate. The FucoPol was produced by the bacteria Enterobacter A47 using glycerol as carbon source at controlled temperature and pH (30ºC and 7, respectively). At the end of 3 days it was produced 7 g/L of FucoPol. The net yield of Fucopol in glycerol (YP/S) was 0.22 g/g and the maximum productivity 2.37 g/L.d This polymer was characterized about its composition in sugars and acyl groups (by High-Performance Liquid Chromatography - HPLC), containing fucose (35 % mol), galactose (21 % mol), glucose (29 % mol), rhamnose (3% mol) and glucuronic acid (12% mol) as well as acetate (14.28 % mol), pyruvate (2.15 % mol) and succinate (1.80 % mol). Its content of water and ash was 15% p/p and 2% p/p, respectively, and the chemical bonds (determined by Infrared Spectroscopy - FT-IR) are consistent to the literature reports. However, due to limitations in Differential Scanning Calorimetry (DSC) equipment it was not possible to determine the glass transition temperature. In turn, the ionic liquid showed the typical behavior of a Newtonian fluid, glass transition temperature (determined by DSC) -98.03ºC and density 1.1031 g/cm3. The study of chemical bonds by FT-IR showed that amount of water (8.80%) influenced the visualization of the bands predicted to in view of their chemical structure. After the dissolution of the FucoPol in the ionic liquid at different temperatures (50, 60, 80 and 100 ° C) it was promoted the removal of this by the phase inversion method using deionized water as a solvent, followed by drying in an oven at 70 ° C. The mixtures before and after the phase inversion method were characterized through the studies mentioned above. In order to explore possible application field’s biocompatibility assays and collage on balsa wood tests were performed. It was found that the process of washing with water by the phase inversion method was not totally effective in removing the biocompatible ionic liquid, since all FucoPol – IL mixtures still contained ionic liquid in their composition as can be seen by the DSC results and FT-IR. In addition, washing the mixtures with water significantly altered the composition of FucoPol. However, these mixtures, that developed a viscous behavior typical of a non-Newtonian fluid (shear-thinning), have the potential to be applied in the biomedical field as well as biological glues.

Validação de limpeza de equipamentos para produção de fórmulas líquidas e pastosas

A utilização de equipamentos multiproduto é uma prática bastante comum em indústria farmacêutica. No entanto, a esta prática podem associar-se riscos de transferência de contaminantes sendo de extrema importância garantir a eficácia dos procedimentos de limpeza estabelecidos. Esta dissertação tem como objetivo a validação de limpeza dos equipamentos do setor das Formas Líquidas e Pastosas (FLP), dos Laboratórios Atral, SA por forma a evidenciar a eficácia e eficiência destes procedimentos na remoção de substâncias ativas (SA), excipientes e agentes de limpeza (tipos de contaminantes). Tendo em conta a diversidade de produtos e equipamentos do setor, recorreu-se a uma análise de risco para identificação de equipamentos e produtos pior-caso. A partir desta análise será também possível identificar os resíduos de substância ativa a procurar após higienização de um determinado equipamento. Para tal, foi necessário estabelecer e validar métodos de análise em HPLC (High Performance Liquid Chromatography) capazes de identificar e quantificar os resíduos das SAs em questão. A baixa frequência de produção de alguns dos produtos pior-caso impossibilitou o terminar dos estudos de validação de limpeza para o agitador de hélice e equipamentos de produção de cremes. O desenvolvimento destes procedimentos permitirá identificar potenciais riscos anteriormente desconhecidos, bem como a recolha e elaboração de documentos comprovativos da capacidade e adequabilidade dos procedimentos de limpeza aplicados.

Optimisation and design of post-tensioning anchorage corner blisters in concrete box girder bidges

The design of anchorage blisters of internal continuity post-tensioning tendons of bridges built by the cantilever method, presents some peculiarities, not only because they are intermediate anchorages but also because these anchorages are located in blisters, so the prestressing force has to be transferred from the blister the bottom slab and web of the girder. The high density of steel reinforcement in anchorage blisters is the most common reason for problems with concrete cast in situ, resulting in zones with low concrete compacity, leading to concrete crushing failures under the anchor plates. A solution may involve improving the concrete compression and tensile strength. To meet these requirements a high-performance fibre reinforced self-compacting mix- ture (HPFRC) was used in anchorage corner blisters of post-tensioning tendons, reducing the concrete cross-section and decreasing the reinforcement needed. To assess the ultimate capacity and the adequate serviceability of the local anchorage zone after reducing the minimum concrete cross-section and the confining reinforcement, specified by the anchorage device supplier for the particular tendon, load transfer tests were performed. To investigate the behaviour of anchorage blisters regarding the transmission of stresses to the web and the bottom slab of the girder, and the feasibility of using high performance concrete only in the blister, two half scale models of the inferior corner of a box girder existing bridge were studied: a reference specimen of ordinary reinforced concrete and a HPFRC blister specimen. The design of the reinforcement was based in the tensile forces obtained on strut-and-tie models. An experimental program was carried out to assess the models used in design and to study the feasibility of using high performance concrete only in the blister, either with casting in situ, or with precast solutions. A non-linear finite element analysis of the tested specimens was also performed and the results compared.

Sol-gel entrapped biosystems: enzyme(s) and whole cells

In this work two different procedures to utilize the sol-gel technology were applied to immobilize/encapsulate enzymes and living cells. CO2 has reached levels in the atmosphere that make it a pollutant. New methods to utilize this gas to obtain products of added value can be very important, both from an environmentally point of view and from an economic standpoint. The first goal of this work was to study the first reaction of a sequential, three-step, enzymatic process that carries out the conversion of CO2 to methanol. Of the three oxidoreductases involved, our focus was on formate dehydrogenase (FateDH) that converts CO2 to formate. This reaction requires the presence of the cofactor β-nicotinamide adenine dinucleotide in reduced form (NADH). The cofactor is expensive and unstable. Our experiments were directed towards generating NADH from its oxidized form (NAD+), using glutamate dehydrogenase (GDH). The formation of NADH from NAD+ in aqueous medium was studied with both free and sol-gel entrapped GDH. This reaction was then followed by the conversion of CO2 to formate, catalysed by free or sol-gel entrapped FateDH. The quantification of NADH/NAD+ was made using UV/Vis spectroscopy. Our results showed that it was possible to couple the GDH-catalyzed generation of the cofactor NADH with the FateDH-catalyzed conversion of CO2, as confirmed by the detection of formate in the medium, using High Performance Liquid Chromatography (HPLC). The immobilization of living cells can be advantageous from the standpoint of ease of recovery, reutilization and physical separation from the medium. Also dead cells may not always exhibit enzymatic activities found with living cells. In this work cell encapsulation was performed using Escherichia coli bacteria. To reduce toxicity for living organisms, the sol-gel method was different than for enzymes, and involved the use of aqueous-based precursors. Initial encapsulation experiments and viability tests were carried out with E. coli K12. Our results showed that sol-gel entrapment of the cells was achieved, and that cell viability could be increased with additives, namely betaine that led to greater viability improvement and was selected for further studies. For an approach to “in-cell” Nuclear Magnetic Resonance (NMR) experiments, the expression of the protein ctCBM11 was performed in E. coli BL21. It was possible to obtain an NMR signal from the entrapped cells, a considerable proportion of which remained alive after the NMR experiments. However, it was not possible to obtain a distinctive NMR signal from the target protein to distinguish it from the other proteins in the cell.

Asking why

The growth of a solid, knowledge-intensive firm, OutSystems—an IT company recognized in 2003 by Fortune magazine as one of the most promising start-ups in the world—is accompanied by efforts to create a strong culture that preserves the traits that have driven OutSystems’ success and that drives innovation, adaptability, high performance, and accountability. The lessons OutSystems learned from previous international experiences are presented along with its latest growth model of branded local partners. The case study is intended to introduce concepts related to organizational culture, traits of cultures that drive innovation, national versus organizational culture, and the challenges of globalization. It is designed to be used in Organizational Behavior classes and is appropriate for MBA- and Master’s-level courses in the area of management. It is suggested as a guideline for 60- to 90-minute classes. Participants are invited to discuss the importance of organizational cultures and their fit with the company strategy. Participants are also encouraged to brainstorm about the best approach to face OutSystems’ new stage of growth, specifically the advantages and consequences of growing as a metanational company. Finally, in the conclusion, the most relevant findings taken from the discussions proposed are revisited: The importance of an organizational culture adapted to the market needs and the potential of innovation behind metanational companies. Other considerations are made about: how the case illustrates the importance of leadership, group age, and group size in the process of building a culture; and how OutSystems’ culture solves the apparent contradiction behind adaptable culture.