Volatile terpenoids and C13 norisoprenoids in wines: development of rapid methods of analysis and evaluation of the sesquiterpenoids biological potential

Vitis vinifera L., the most widely cultivated fruit crop in the world, was the starting point for the development of this PhD thesis. This subject was exploited following on two actual trends: i) the development of rapid, simple, and high sensitive methodologies with minimal sample handling; and ii) the valuation of natural products as a source of compounds with potential health benefits. The target group of compounds under study were the volatile terpenoids (mono and sesquiterpenoids) and C13 norisoprenoids, since they may present biological impact, either from the sensorial point of view, as regards to the wine aroma, or by the beneficial properties for the human health. Two novel methodologies for quantification of C13 norisoprenoids in wines were developed. The first methodology, a rapid method, was based on the headspace solid-phase microextraction combined with gas chromatography-quadrupole mass spectrometry operating at selected ion monitoring mode (HS-SPME/GC-qMS-SIM), using GC conditions that allowed obtaining a C13 norisoprenoid volatile signature. It does not require any pre-treatment of the sample, and the C13 norisoprenoid composition of the wine was evaluated based on the chromatographic profile and specific m/z fragments, without complete chromatographic separation of its components. The second methodology, used as reference method, was based on the HS-SPME/GC-qMS-SIM, allowing the GC conditions for an adequate chromatographic resolution of wine components. For quantification purposes, external calibration curves were constructed with ��-ionone, with regression coefficient (r2) of 0.9968 (RSD 12.51 %) and 0.9940 (RSD of 1.08 %) for the rapid method and for the reference method, respectively. Low detection limits (1.57 and 1.10 ��g L-1) were observed. These methodologies were applied to seventeen white and red table wines. Two vitispirane isomers (158-1529 L-1) and 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) (6.42-39.45 ��g L-1) were quantified. The data obtained for vitispirane isomers and TDN using the two methods were highly correlated (r2 of 0.9756 and 0.9630, respectively). A rapid methodology for the establishment of the varietal volatile profile of Vitis vinifera L. cv. 'Fern��o-Pires' (FP) white wines by headspace solid-phase microextraction combined with comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (HS-SPME/GCxGC-TOFMS) was developed. Monovarietal wines from different harvests, Appellations, and producers were analysed. The study was focused on the volatiles that seem to be significant to the varietal character, such as mono and sesquiterpenic compounds, and C13 norisoprenoids. Two-dimensional chromatographic spaces containing the varietal compounds using the m/z fragments 93, 121, 161, 175 and 204 were established as follows: 1tR = 255-575 s, 2tR = 0,424-1,840 s, for monoterpenoids, 1tR = 555-685 s, 2tR = 0,528-0,856 s, for C13 norisoprenoids, and 1tR = 695-950 s, 2tR = 0,520-0,960 s, for sesquiterpenic compounds. For the three chemical groups under study, from a total of 170 compounds, 45 were determined in all wines, allowing defining the "varietal volatile profile" of FP wine. Among these compounds, 15 were detected for the first time in FP wines. This study proposes a HS-SPME/GCxGC-TOFMS based methodology combined with classification-reference sample to be used for rapid assessment of varietal volatile profile of wines. This approach is very useful to eliminate the majority of the non-terpenic and non-C13 norisoprenic compounds, allowing the definition of a two-dimensional chromatographic space containing these compounds, simplifying the data compared to the original data, and reducing the time of analysis. The presence of sesquiterpenic compounds in Vitis vinifera L. related products, to which are assigned several biological properties, prompted us to investigate the antioxidant, antiproliferative and hepatoprotective activities of some sesquiterpenic compounds. Firstly, the antiradical capacity of trans,trans-farnesol, cis-nerolidol, ��-humulene and guaiazulene was evaluated using chemical (DPPH��� and hydroxyl radicals) and biological (Caco-2 cells) models. Guaiazulene (IC50= 0.73 mM) was the sesquiterpene with higher scavenger capacity against DPPH���, while trans,trans-farnesol (IC50= 1.81 mM) and cis-nerolidol (IC50= 1.48 mM) were more active towards hydroxyl radicals. All compounds, with the exception of ��-humulene, at non-cytotoxic levels (��� 1 mM), were able to protect Caco-2 cells from oxidative stress induced by tert-butyl hydroperoxide. The activity of the compounds under study was also evaluated as antiproliferative agents. Guaiazulene and cis-nerolidol were able to more effectively arrest the cell cycle in the S-phase than trans,trans-farnesol and ��-humulene, being the last almost inactive. The relative hepatoprotection effect of fifteen sesquiterpenic compounds, presenting different chemical structures and commonly found in plants and plant-derived foods and beverages, was assessed. Endogenous lipid peroxidation and induced lipid peroxidation with tert-butyl hydroperoxide were evaluated in liver homogenates from Wistar rats. With the exception of ��-humulene, all the sesquiterpenic compounds under study (1 mM) were effective in reducing the malonaldehyde levels in both endogenous and induced lipid peroxidation up to 35% and 70%, respectively. The developed 3D-QSAR models, relating the hepatoprotection activity with molecular properties, showed good fit (R2LOO > 0.819) with good prediction power (Q2 > 0.950 and SDEP < 2%) for both models. A network of effects associated with structural and chemical features of sesquiterpenic compounds such as shape, branching, symmetry, and presence of electronegative fragments, can modulate the hepatoprotective activity observed for these compounds. In conclusion, this study allowed the development of rapid and in-depth methods for the assessment of varietal volatile compounds that might have a positive impact on sensorial and health attributes related to Vitis vinifera L. These approaches can be extended to the analysis of other related food matrices, including grapes and musts, among others. In addition, the results of in vitro assays open a perspective for the promising use of the sesquiterpenic compounds, with similar chemical structures such as those studied in the present work, as antioxidants, hepatoprotective and antiproliferative agents, which meets the current challenges related to diseases of modern civilization.

Estrat��gias de altera����o da funcionalidade de prote��nas de soja

Este trabalho teve como principal objetivo estudar e modificar as propriedades funcionais das prote��nas de soja de forma a otimizar e diversificar a sua aplica����o industrial. Para tal, foram propostas e estudadas quatro estrat��gias: i) extra����o do isolado de prote��nas de soja (IPS) a partir de diferentes mat��rias-primas, ii) adi����o de galactomananas (GM) com graus de ramifica����o e massas moleculares diferentes, iii) hidr��lise enzim��tica controlada das prote��nas de soja, iv) processamento por alta press��o hidrost��tica. O estudo e a interpreta����o da influ��ncia destas estrat��gias sobre as propriedades funcionais das prote��nas de soja, nomeadamente, na capacidade gelificante e emulsionante, foram realizados recorrendo fundamentalmente a ensaios reol��gicos din��micos a baixas deforma����o, espectroscopia de infravermelho, electroforeses, calorimetria diferencial de varrimento e ensaios de microscopia confocal de varrimento laser. O estudo da extra����o e caracteriza����o dos isolados de prote��nas de soja obtidos a partir de diferentes mat��rias-primas permitiu concluir que as carater��sticas f��sico-qu��micas dos isolados s��o dependentes da origem da mat��ria-prima de extra����o e da severidade dos tratamentos industriais pr��vios �� extra����o do isolado. Contudo, as propriedades viscoel��sticas dos g��is obtidos por aquecimento controlado n��o foram significativamente distintas embora tenha sido poss��vel relacionar o grau de agrega����o com a diminui����o da temperatura de gelifica����o e com o aumento inicial dos m��dulos viscoel��sticos. As altera����es sofridas pelos isolados de origem comercial mostraram ser irrevers��veis resultando em g��is menos r��gidos e com maior car��ter viscoso. A adi����o de galactomanana alterou significativamente o mecanismo de gelifica����o induzido termicamente das prote��nas de soja, bem como as propriedades viscoel��sticas dos g��is e a microestrutura dos g��is, demonstrando-se a ocorr��ncia de separa����o de fases, em virtude da incompatibilidade termodin��mica entre os biopol��meros, resultando em g��is mais r��gidos e no decr��scimo da temperatura de gelifica����o. A extens��o destas altera����es foi dependente da massa molecular, grau de ramifica����o e da raz��o IPS/GM. O efeito da hidr��lise enzim��tica por a����o da bromelina, nas propriedades gelificantes e emulsionantes das prote��nas de soja, mostrou ser dependente do grau de hidr��lise (GH). Valores de GH inferiores a 15 % melhoraram as propriedades gelificantes das prote��nas de soja. Por outro lado, o aumento do GH teve um efeito negativo nas propriedades emulsionantes, o qual foi atenuado por adi����o da goma de alfarroba, com efeito positivo na gelifica����o das prote��nas de soja. A concentra����o cr��tica limite de compatibilidade entre os hidrolisados de prote��na de soja e a goma de alfarroba aumentou com o decr��scimo do GH e da massa molecular do polissacacr��deo. O efeito da AP sobre as propriedades f��sico-qu��micas e funcionais dos IPS foi influenciado pela origem do isolado e pelas condi����es de tratamento. O processamento at�� 100 MPa desencadeou um aumento da atividade emulsionante e consider��vel melhoria da capacidade gelificante. Contudo, valores de press��o superiores promoveram a desnatura����o das prote��nas constituintes dos isolados, resultando no decr��scimo da temperatura de gelifica����o e numa re-associa����o das subunidades proteicas, diminuindo a elasticidade dos g��is finais. Os resultados sugeriram que as altera����es nas prote��nas de soja promovidas durante o tratamento por AP constituem um fator limitante para o desdobramento e re-associa����o durante o aquecimento t��rmico, necess��rios para a forma����o e fortalecimento de gel formado. O processamento por AP influenciou a estrutura secund��ria e a microestrutura das amostras. A presen��a de GA teve um papel baroprotetor. Assim, com este trabalho demonstrou-se que com as estrat��gias seguidas para manipula����o das propriedades funcionais de prote��nas de soja, nomeadamente atrav��s da adi����o de um polissacar��deo com propriedades estruturais controladas, da adequada combinação da adi����o de um polissacar��deo neutro com a hidr��lise controlada das prote��nas ou com tratamento por alta press��o, �� poss��vel a cria����o de novas funcionalidades, com utilidade no desenvolvimento de novas formula����es alimentares, permitindo expandir a aplica����o destas prote��nas vegetais.

Metal-organic frameworks based on phosphonate linkers

During the last few decades, Metal-Organic Frameworks (MOFs), also known as Coordination Polymers, have attracted worldwide research attentions due to their incremented fascinating architectures and unique properties. These multidimensional materials have been potential applications in distinct areas: gas storage and separation, ion exchange, catalysis, magnetism, in optical sensors, among several others. The MOF research group at the University of Aveiro has prepared MOFs from the combination of phosphonate organic primary building units (PBUs) with, mainly, lanthanides. This thesis documents the last findings in this area involving the synthesis of multidimensional MOFs based on four di- or tripodal phosphonates ligands. The organic PBUs were designed and prepared by selecting and optimizing the best reaction conditions and synthetic routes. The self-assembly between phosphonate PBUs and rare-earths cations led to the formation of several 1D, 2D and 3D families of isotypical MOFs. The preparation of these materials was achieved by using distinct synthetic approaches: hydro(solvo)thermal, microwave- and ultrasound-assisted, one-pot and ionothermal synthesis. The selection of the organic PBUs showed to have an important role in the final architectures: while flexible phosphonate ligands afforded 1D, 2D and dense 3D structures, a large and rigid organic PBU isolated a porous 3D MOF. The crystal structure of these materials was successfully unveiled by powder or single-crystal X-ray diffraction. All multidimensional MOFs were characterized by standard solid-state techniques (FT-IR, electron microscopy (SEM and EDS), solid-state NMR, elemental and thermogravimetric analysis). Some MOF materials exhibited remarkable thermal stability and robustness up to ca. 400 ��C. The intrinsic properties of some MOFs were investigated. Photoluminescence studies revealed that the selected organic PBUs are suitable sensitizers of Tb3+ leading to the isolation of intense green-emitting materials. The suppression of the O���H quenchers by deuteration or dehydration processes improves substantially the photoluminescence of the optically-active Eu3+-based materials. Some MOF materials exhibited high heterogeneous catalytic activity and excellent regioselectivity in the ring-opening reaction of styrene oxide (PhEtO) with methanol (100% conversion of PhEtO at 55 ��C for 30 min). The porous MOF material was employed in gas separation processes. This compound showed the ability to separate propane over propylene. The ionexchanged form of this material (containing K+ cations into its network) exhibited higher affinity for CO2 being capable to separate acetylene over this environment non-friendly gas.

Coping, fatores psicossociais e capacidade para o trabalho

O coping desempenha um importante papel na sa��de individual e rendimento organizacional. Tal como o coping �� um tema de interesse recente e promissor na ��rea da psicologia da sa��de ocupacional, tamb��m os fatores psicossociais do trabalho t��m ganho um crescente interesse no dom��nio da sa��de ocupacio-nal. No entanto, pouco se sabe acerca das configura����es de coping mais salu-tog��nicas no mundo do trabalho, e menos ainda acerca da participa����o dos fatores psicossociais na defini����o das mesmas. Esta ��ltima perspetiva assume os fatores psicossociais n��o como causas de stresse, mas enquanto recursos de coping. Com o presente estudo, desej��vamos saber se as pessoas com melhor sa��de no trabalho usam estrat��gias de coping diferentes daquelas com menor sa��de, bem como se a escolha dessas estrat��gias �� influenciada pelos fatores psicossociais do trabalho. Pretendia-se ainda caracterizar o coping dos trabalhadores mais saud��veis e produtivos, e perceber que fatores psicosso-ciais contribuem para o mesmo. Foram estudados 2960 profissionais de traba-lhos mentais, sendo 31% (n=909) profissionais de sa��de e 69% (n=2051) pro-fissionais de outras ��reas. Al��m das vari��veis sociodemogr��ficas, avaliou-se o coping (Brief COPE), os fatores psicossociais do trabalho (COPSOQ) e o ��ndi-ce de capacidade para o trabalho (ICT), enquanto indicador de sa��de ocupa-cional. Desenhou-se um estudo transversal e quantitativo, com n��veis de an��li-se descritivo, explorat��rio, correlacional e preditivo. Os resultados confirmaram as hip��teses de estudo e permitem concluir genericamente que (1) o coping diferencia e determina a sa��de no trabalho, (2) os fatores psicossociais do trabalho influenciam o coping, ainda que modestamente, e (3) o coping dos profissionais de sa��de �� estruturalmente diferente do coping dos n��o profissio-nais de sa��de. Os resultados possibilitam ainda estabelecer perfis de bom e de mau coping no trabalho e concorrem para definir estrat��gias de interven����o psicol��gica para o desenvolvimento do report��rio de coping dos profissionais de trabalhos mentais, bem como estrat��gias de gest��o (de recursos humanos) para a melhoria do ambiente psicossocial do trabalho. Por fim, os resultados estimulam algumas considera����es te��ricas e metodol��gicas que sugerem dire����es futuras para o estudo dos efeitos da rela����o do coping com o ambien-te psicossocial do trabalho na sa��de e bem-estar individual, no rendimento organizacional e na qualidade de vida no trabalho. Julgamos, por fim, que os resultados obtidos podem contribuir para aprimorar os mecanismos de coping dos profissionais e para ajustar o ambiente psicossocial do trabalho.

Expanded porphyrins and their evaluation as anion chemosensors

Expanded porphyrins are synthetic analogues of porphyrins, differing from the last ones and other naturally occurring tetrapyrrolic macrocycles by containing a larger central core, with a minimum of 17 atoms, while retaining the extended conjugation features that are a tremendous feature of these biological pigments. The core expansion results in various systems with novel spectral and electronic features, often uniques. Most of these systems can also coordinate cations and/or anions, and in some cases they can bind more than one of these species. In many cases, these molecules display structural features, such as non-planar structures, that have no antecedents in the chemistry of porphyrins or related macrocyclic compounds. This work will discuss several synthetic approaches for the synthesis of expanded porphyrins, namely the construction of new building blocks by Michael addition, as well as potential synthetic routes towards expanded porphyrins. The synthesis of smaller oligopyrrolic compounds namely, bipyrroles and dipyrromethanes, not only were developed for the synthesis of expanded porphyrins as they were also used in Knoevenagel condensations furnishing chromogenic compounds able to recognize different anions in solution. Also, an approach to the synthesis of novel expanded porphyrins namely sapphyrins has been done by aza-Michael additions. Several synthetic routes towards the synthesis of pyridyl and pyridinium N-Fused pentaphyrins and hexaphyrins have been explored in order to achieve compounds with potential applications in catalysis and PDI, respectively. Studies on the synthesis of compounds with potential anion binding properties, led to the structural characterization and NMR anion binding studies of [28]hexaphyrins functionalized with several diamines in the para position of their pentafluorophenyl groups. These compounds allow NH hydrogen bond interactions with various anions. All synthesized compounds were fully characterized by modern spectroscopic techniques.

Derivation of soil screening values for metals in Portuguese natural soil

The increasing human activity has been responsible by profound changes and a constinuos degradation of the soil compartment in all the European territory. Some European policies are appearing focusing soil���s protection and the management of contaminated sites, in order to recover land for other uses. To regulate the risk assessment and the management of contaminated soils, many European member states adopted soil guideline values, as for example soil screnning values (SSV).These values are particularly useful for the the first tier of the Ecological Risk Assessment (ERA) processes of contaminated sites,especially for a first screening of sites requiring a more site-specific evaluation. Hence, the approriate definition of regional SSVs will have relevant economic impacts in the management of contaminated sites. Portugal is one of European Member States that still lack these soil guideline values. In this context, this study gaves a remarkable contribution in the generation of ecotoxicological data for soil microbiological parameters, terrestrial plants and invertebrates for the derivation of SSVs for uranium (U), cadmium (Cd) and copper (Cu), using a Portuguese natural soil, representative of a dominant type of soil in the Portuguese territory. SSVs were derived based on two methods proposed by the the Technical Guidance Document for Risk Assessment of the European Commission; namely the assessment factor method (AF) and the species sensitivity distribution (SSD) method (with some adaptations). The outputs of both methods were compared and discussed. Further, this study laid the foundation for a deeper reflection about the cut-off (hazard concentration for a given percentage of species - HCps) to be estimated from the SSDs, and to be selected for the derivation of SSVs, with the adequate level of protection. It was proven that this selection may vary for different contaminants, however a clear justification should be given, in each case. The SSvs proposed in this study were for: U (151.4 mg U kg-1dw), Cd (5.6 mg Cd kg-1dw), and Cu (58.5 mg Cu kg-1dw) These values should now be tested for their descriminating power of soils with different levels of contamination. However, this studies clarifies the approach that should be followed for the derivation of SSVs for other metals and organic contaminants, and for other dominant types of Portuguese natural soils.

Novel hardware and software combination for automotive motorsport vehicles based on direct processing of graphical functions

The main motivation for the work presented here began with previously conducted experiments with a programming concept at the time named "Macro". These experiments led to the conviction that it would be possible to build a system of engine control from scratch, which could eliminate many of the current problems of engine management systems in a direct and intrinsic way. It was also hoped that it would minimize the full range of software and hardware needed to make a final and fully functional system. Initially, this paper proposes to make a comprehensive survey of the state of the art in the specific area of software and corresponding hardware of automotive tools and automotive ECUs. Problems arising from such software will be identified, and it will be clear that practically all of these problems stem directly or indirectly from the fact that we continue to make comprehensive use of extremely long and complex "tool chains". Similarly, in the hardware, it will be argued that the problems stem from the extreme complexity and inter-dependency inside processor architectures. The conclusions are presented through an extensive list of "pitfalls" which will be thoroughly enumerated, identified and characterized. Solutions will also be proposed for the various current issues and for the implementation of these same solutions. All this final work will be part of a "proof-of-concept" system called "ECU2010". The central element of this system is the before mentioned "Macro" concept, which is an graphical block representing one of many operations required in a automotive system having arithmetic, logic, filtering, integration, multiplexing functions among others. The end result of the proposed work is a single tool, fully integrated, enabling the development and management of the entire system in one simple visual interface. Part of the presented result relies on a hardware platform fully adapted to the software, as well as enabling high flexibility and scalability in addition to using exactly the same technology for ECU, data logger and peripherals alike. Current systems rely on a mostly evolutionary path, only allowing online calibration of parameters, but never the online alteration of their own automotive functionality algorithms. By contrast, the system developed and described in this thesis had the advantage of following a "clean-slate" approach, whereby everything could be rethought globally. In the end, out of all the system characteristics, "LIVE-Prototyping" is the most relevant feature, allowing the adjustment of automotive algorithms (eg. Injection, ignition, lambda control, etc.) 100% online, keeping the engine constantly working, without ever having to stop or reboot to make such changes. This consequently eliminates any "turnaround delay" typically present in current automotive systems, thereby enhancing the efficiency and handling of such systems.

Ferroelectric : CNTs structures fabrication for advanced functional nano devices

This work is about the combination of functional ferroelectric oxides with Multiwall Carbon Nanotubes for microelectronic applications, as for example potential 3 Dimensional (3D) Non Volatile Ferroelectric Random Access Memories (NVFeRAM). Miniaturized electronics are ubiquitous now. The drive to downsize electronics has been spurred by needs of more performance into smaller packages at lower costs. But the trend of electronics miniaturization challenges board assembly materials, processes, and reliability. Semiconductor device and integrated circuit technology, coupled with its associated electronic packaging, forms the backbone of high-performance miniaturized electronic systems. However, as size decreases and functionalization increases in the modern electronics further size reduction is getting difficult; below a size limit the signal reliability and device performance deteriorate. Hence miniaturization of siliconbased electronics has limitations. On this background the Road Map for Semiconductor Industry (ITRS) suggests since 2011 alternative technologies, designated as More than Moore; being one of them based on carbon (carbon nanotubes (CNTs) and graphene) [1]. CNTs with their unique performance and three dimensionality at the nano-scale have been regarded as promising elements for miniaturized electronics [2]. CNTs are tubular in geometry and possess a unique set of properties, including ballistic electron transportation and a huge current caring capacity, which make them of great interest for future microelectronics [2]. Indeed CNTs might have a key role in the miniaturization of Non Volatile Ferroelectric Random Access Memories (NVFeRAM). Moving from a traditional two dimensional (2D) design (as is the case of thin films) to a 3D structure (based on a tridimensional arrangement of unidimensional structures) will result in the high reliability and sensing of the signals due to the large contribution from the bottom electrode. One way to achieve this 3D design is by using CNTs. Ferroelectrics (FE) are spontaneously polarized and can have high dielectric constants and interesting pyroelectric, piezoelectric, and electrooptic properties, being a key application of FE electronic memories. However, combining CNTs with FE functional oxides is challenging. It starts with materials compatibility, since crystallization temperature of FE and oxidation temperature of CNTs may overlap. In this case low temperature processing of FE is fundamental. Within this context in this work a systematic study on the fabrication of CNTs - FE structures using low cost low temperature methods was carried out. The FE under study are comprised of lead zirconate titanate (Pb1-xZrxTiO3, PZT), barium titanate (BaTiO3, BT) and bismuth ferrite (BiFeO3, BFO). The various aspects related to the fabrication, such as effect on thermal stability of MWCNTs, FE phase formation in presence of MWCNTs and interfaces between the CNTs/FE are addressed in this work. The ferroelectric response locally measured by Piezoresponse Force Microscopy (PFM) clearly evidenced that even at low processing temperatures FE on CNTs retain its ferroelectric nature. The work started by verifying the thermal decomposition behavior under different conditions of the multiwall CNTs (MWCNTs) used in this work. It was verified that purified MWCNTs are stable up to 420 ��C in air, as no weight loss occurs under non isothermal conditions, but morphology changes were observed for isothermal conditions at 400 ��C by Raman spectroscopy and Transmission Electron Microscopy (TEM). In oxygen-rich atmosphere MWCNTs started to oxidized at 200 ��C. However in argon-rich one and under a high heating rate MWCNTs remain stable up to 1300 ��C with a minimum sublimation. The activation energy for the decomposition of MWCNTs in air was calculated to lie between 80 and 108 kJ/mol. These results are relevant for the fabrication of MWCNTs ��� FE structures. Indeed we demonstrate that PZT can be deposited by sol gel at low temperatures on MWCNTs. And particularly interesting we prove that MWCNTs decrease the temperature and time for formation of PZT by ~100 ��C commensurate with a decrease in activation energy from 68��15 kJ/mol to 27��2 kJ/mol. As a consequence, monophasic PZT was obtained at 575 ��C for MWCNTs - PZT whereas for pure PZT traces of pyrochlore were still present at 650 ��C, where PZT phase formed due to homogeneous nucleation. The piezoelectric nature of MWCNTs - PZT synthesised at 500 ��C for 1 h was proved by PFM. In the continuation of this work we developed a low cost methodology of coating MWCNTs using a hybrid sol-gel / hydrothermal method. In this case the FE used as a proof of concept was BT. BT is a well-known lead free perovskite used in many microelectronic applications. However, synthesis by solid state reaction is typically performed around 1100 to 1300 ��C what jeopardizes the combination with MWCNTs. We also illustrate the ineffectiveness of conventional hydrothermal synthesis in this process due the formation of carbonates, namely BaCO3. The grown MWCNTs - BT structures are ferroelectric and exhibit an electromechanical response (15 pm/V). These results have broad implications since this strategy can also be extended to other compounds of materials with high crystallization temperatures. In addition the coverage of MWCNTs with FE can be optimized, in this case with non covalent functionalization of the tubes, namely with sodium dodecyl sulfate (SDS). MWCNTs were used as templates to grow, in this case single phase multiferroic BFO nanorods. This work shows that the use of nitric solvent results in severe damages of the MWCNTs layers that results in the early oxidation of the tubes during the annealing treatment. It was also observed that the use of nitric solvent results in the partial filling of MWCNTs with BFO due to the low surface tension (<119 mN/m) of the nitric solution. The opening of the caps and filling of the tubes occurs simultaneously during the refluxing step. Furthermore we verified that MWCNTs have a critical role in the fabrication of monophasic BFO; i.e. the oxidation of CNTs during the annealing process causes an oxygen deficient atmosphere that restrains the formation of Bi2O3 and monophasic BFO can be obtained. The morphology of the obtained BFO nano structures indicates that MWCNTs act as template to grow 1D structure of BFO. Magnetic measurements on these BFO nanostructures revealed a week ferromagnetic hysteresis loop with a coercive field of 956 Oe at 5 K. We also exploited the possible use of vertically-aligned multiwall carbon nanotubes (VA-MWCNTs) as bottom electrodes for microelectronics, for example for memory applications. As a proof of concept BiFeO3 (BFO) films were in-situ deposited on the surface of VA-MWCNTs by RF (Radio Frequency) magnetron sputtering. For in situ deposition temperature of 400 ��C and deposition time up to 2 h, BFO films cover the VA-MWCNTs and no damage occurs either in the film or MWCNTs. In spite of the macroscopic lossy polarization behaviour, the ferroelectric nature, domain structure and switching of these conformal BFO films was verified by PFM. A week ferromagnetic ordering loop was proved for BFO films on VA-MWCNTs having a coercive field of 700 Oe. Our systematic work is a significant step forward in the development of 3D memory cells; it clearly demonstrates that CNTs can be combined with FE oxides and can be used, for example, as the next 3D generation of FERAMs, not excluding however other different applications in microelectronics.

Assessing the effectiveness of chemical treatment with nanomaterials in improving the quality of different industrial effluents

Industrial activities are the major sources of pollution in all environments. Depending on the type of industry, various levels of organic and inorganic pollutants are being continuously discharged into the environment. Although, several kinds of physical, chemical, biological or the combination of methods have been proposed and applied to minimize the impact of industrial effluents, few have proved to be totally effective in terms of removal rates of several contaminants, toxicity reduction or amelioration of physical and chemical properties. Hence, it is imperative to develop new and innovative methodologies for industrial wastewater treatment. In this context nanotechnology arises announcing the offer of new possibilities for the treatment of wastewaters mainly based on the enhanced physical and chemical proprieties of nanomaterials (NMs), which can remarkably increase their adsorption and oxidation potential. Although applications of NMs may bring benefits, their widespread use will also contribute for their introduction into the environment and concerns have been raised about the intentional use of these materials. Further, the same properties that make NMs so appealing can also be responsible for producing ecotoxicological effects. In a first stage, with the objective of selecting NMs for the treatment of organic and inorganic effluents we first assessed the potential toxicity of nanoparticles of nickel oxide (NiO) with two different sizes (100 and 10-20 nm), titanium dioxide (TiO2, < 25 nm) and iron oxide (Fe2O3, ��� 85x425 nm). The ecotoxicological assessment was performed with a battery of assays using aquatic organisms from different trophic levels. Since TiO2 and Fe2O3 were the NMs that presented lower risks to the aquatic systems, they were selected for the second stage of this work. Thus, the two NMs pre-selected were tested for the treatment of olive mill wastewater (OMW). They were used as catalyst in photodegradation systems (TiO2/UV, Fe2O3/UV, TiO2/H2O2/UV and Fe2O3/H2O2/UV). The treatments with TiO2 or Fe2O3 combined with H2O2 were the most efficient in ameliorating some chemical properties of the effluent. Regarding the toxicity to V. fischeri the highest reduction was recorded for the H2O2/UV system, without NMs. Afterwards a sequential treatment using photocatalytic oxidation with NMs and degradation with white-rot fungi was applied to OMW. This new approach increased the reduction of chemical oxygen demand, phenolic content and ecotoxicity to V. fischeri. However, no reduction in color and aromatic compounds was achieved after 21 days of biological treatment. The photodegradation systems were also applied to treat the kraft pulp mill and mining effluents. For the organic effluent the combination NMs and H2O2 had the best performances in reduction the chemical parameters as well in terms of toxicity reduction. However, for the mine effluent the best (TiO2/UV and Fe2O3/UV) were only able to significantly remove three metals (Zn, Al and Cd). Nonetheless the treatments were able of reducing the toxicity of the effluent. As a final stage, the toxicity of solid wastes formed during wastewater treatment with NMs was assessed with Chironomus riparius larvae, a representative species of the sediment compartment. Certain solid wastes showed the potential to negatively affect C. riparius survival and growth, depending on the type of effluent treated. This work also brings new insights to the use of NMs for the treatment of industrial wastewaters. Although some potential applications have been announced, many evaluations have to be performed before the upscaling of the chemical treatments with NMs.

Avalia����o da biologia reprodutiva do cagarro Calonectris diomedea borealis no arquip��lago dos A��ores

Disserta����o mest., Biologia Marinha, Universidade do Algarve, 2008

A extraordin��ria capacidade de perdoar: implica����es na (re)constru����o da felicidade

Hoje, como nunca antes, as ci��ncias humanas e sociais consubstanciam um corpo consistente e unificado de dados rigorosos que sublinham as descri����es do ���florescimento humano��� (flourishing) de quem, surpreendentemente, optou por perdoar, n��o obstante a complexidade das condi����es, circunstancias e situa����es profundamente devastadoras fizessem supor o contr��rio, e de quem aceitou deixar-se ���tocar��� pelo acto sublime de ser perdoado. Intacta na densidade do pensamento filos��fico e teol��gico, que irrompeu ao longo da hist��ria, a extraordin��ria arte de perdoar deixou-se escapar dos seus manuais para, tamb��m, encontrar o seu devido lugar no sistema de pensamento cient��fico, dentro de um quadro rigoroso e metodol��gico que configura o actual rumo tomado pelas ci��ncias do funcionamento humano ��ptimo que consubstancia o emergente movimento da Psicologia Positiva (McCullough, 2000; Peterson & Seligman, 2004; Seligman, 2006). A centralidade deste trabalho inscreve a intencionalidade de analisar a rela����o entre o fen��meno psicol��gico do perd��o interpessoal e as suas implica����es na reconstru����o da felicidade daquele cuja praticabilidade dessa ���for��a��� positiva se afigura como uma realidade poss��vel, partindo da analise das rela����es entre vari��veis psicol��gicas (tra��os de personalidade) e factores sociodemograficos (e.g., a idade, o g��nero, a religiosidade e o envolvimento religioso na pr��xis da catequese) tanto no perd��o disposicional quanto na felicidade ou bem-estar subjectivo e, ainda, na influ��ncia que estes dois constructos exercem entre si. Justamente porque uma Psicologia do Perd��o encontra n��o somente a sua raiz no horizonte da Psicologia das Rela����es Interpessoais mas, na sua inevitabilidade, apela a uma dimens��o tanto teol��gica e espiritual quanto psicossocial (McCullough, 2000, 2001; McCullough et al., 1997, 1998, 2001; McCullough & Worthington, 1999),posicionamos o estudo numa amostra que, por um lado, consubstancia uma forte componente interpessoal na sua profissionalidade (um contexto educativo, um contexto de profiss��es de ajuda do dom��nio da sa��de e um contexto administrativo) e, por outro lado, inscreve participantes portadores de uma religiosidade que se exprime por um forte envolvimento religioso na pr��xis da catequese. Foram inquiridos 158 participantes dos tr��s contextos que consubstanciam a amostra global. Para a avalia����o das vari��veis em estudo que influem na rela����o entre a ���for��a��� do perd��o e a felicidade, utilizamos a Escala unifactorial sobre a disposi����o para o perd��o interpessoal (Barros, 2002, 2004), a Escala sobre a propens��o para o perd��o (Mullet, et al., 2003), o Invent��rio de Personalidade ��� NEO-FFI (Costa & McCrae, 1992; Lima & Sim��es, 2002; Sim��es et al., 2001), a Escala de satisfa����o com a Vida (Diener et al., 1985; Sim��es, 1992) e as Escalas da Afectividade Positiva e da Afectividade Negativa (Watson, Clark, & Tellegen, 1988; Sim��es, 1993). Se, por um lado, os resultados obtidos sugerem que a ���for��a��� do perd��o est�� n��o apenas positivamente associada com a religiosidade e o envolvimento religioso dos sujeitos mas que, encontra uma maior depend��ncia com os tra��os de personalidade comparativamente aos factores sociodemogr��ficos, por outro lado, apontam que o perd��o disposicional �� uma vari��vel preditora na felicidade ou bem-estar subjectivo dos participantes. Estes resultados remetem para importantes implica����es. A investiga����o sobre a tem��tica do perd��o interpessoal contribui, de forma significativa, n��o somente para a constru����o de uma Psicologia do Perd��o no quadro global da Psicologia das Rela����es Interpessoais e, por extens��o, da Psicologia da Educa����o mas, contemporaneamente, configura um processo psicol��gico sustent��vel ao florescimento humano e �� felicidade aut��ntica.

Identification of genes regulated by mir-363*, a regulator of bone marrow endothelial cell properties

As c��lulas estaminais hematopoi��ticas residem na medula ��ssea e possuem capacidade para se auto-renovar e dar origem a todos os tipos de c��lulas sangu��neas. O endot��lio da medula ��ssea �� constitu��do por c��lulas endoteliais de medula ��ssea (BMEC) e compreende dois nichos com fun����es distintas: o nicho osteobl��stico e o nicho vascular. O nicho osteobl��sctico proporciona condi����es para a quiesc��ncia de c��lulas estaminais hematopoi��ticas, enquanto no nicho vascular ocorre prolifera����o e diferencia����o das mesmas. Quando ocorre um desequil��brio na express��o de genes que codificam para prote��nas envolvidas na mobiliza����o de c��lulas do nicho osteobl��stico para o nicho vascular ��� factores angi��crinos ��� ocorre uma desestabiliza����o do microambiente medular, que se pode traduzir num processo tumoral. Os microRNAs (miRNAs) s��o uma classe de RNAs n��o codificantes, de cadeia simples, que regula a express��o g��nica. Os miRNAs s��o sequ��ncias end��genas de RNA que possuem entre 19 e 25 nucle��tidos de tamanho. Os miRNAs s��o reguladores da express��o genica, induzindo o silenciamento a n��vel da p��s-transcri����o, atrav��s da sua liga����o com uma sequ��ncia específica para a qual possuem afinidade, na regi��o 3��� n��o traduzida (3��� UTR) dos seus mRNA alvo, conduzindo �� inibi����o da tradu����o ou �� sua degrada����o. Os miRNAs est��o envolvidos na regula����o de genes de diversas vias afectando processos fundamentais como hematopoiese, apoptose, prolifera����o celular e tumorig��nese. Os n��veis de express��o dos miRNAs est��o alterados no cancro, podendo actuar directamente como supressores de tumor ou como oncogenes, sendo neste caso denominados de oncomirs. Os perfis dos n��veis de express��o de v��rios miRNAs foram estudados, tendo-se verificado que se alteram durante o processo de carcinog��nese, podendo actuar directamente como supressores de tumor ou como oncogenes, sendo neste caso denominados de oncomirs. Apesar do miR-363* estar envolvido na regula����o da express��o de genes que regulam propriedades das c��lulas endoteliais e medula ��ssea, os genes sobre os quais exerce a sua fun����o ainda n��o foram identificados.O objectivo do presente estudo �� a identifica����o dos genes directamente regulados pelo miR-363* (genes alvo) e a sua relev��ncia para a disfun����o medular e a sua caracteriza����o nos s��ndromes mielodispl��sicos. A estrat��gia usada baseou-se na redu����o ou aumento for��ados dos n��veis de miR-363* em c��lulas endoteliais e subsequente an��lise da express��o g��nica atrav��s de microarrays de cDNA do genoma humano. A redu����o do miR-363* vai implicar o aumento da express��o dos seus genes alvo, assim como o aumento dos n��veis do miR-363* vai induzir a degrada����o e consequente redu����o dos seus genes alvos. A intersec����o dos dados gerados atrav��s do estudo da express��o com bases de dados que possuem algoritmos para previs��o de genes alvo directos dos miRNAs (miRBase e MicroCosm Targets) permitiu restringir os genes a analisar a sete genes, nomeadamente BST1, ESAM, FCER1G, IKBKG, SELE, THBS3 e TIMP1. A interac����o directa destes candidatos a alvos directos do miR-363* foi posteriormente validada. Para tal, as 3���UTR dos genes foram clonadas num vector que cont��m o gene da luciferase. Uma vez as clonagens realizadas, efectuaram-se ensaios funcionais em c��lulas endoteliais, nomeadamente HUVEC, nas quais se co-transfectaram os vectores gerados, anti-miRs ou pre-miRs (para diminuir ou aumentar o n��vel de miRNA) e o plasm��deo controlo da Renilla para normaliza����o dos ensaios de luciferase. A varia����o da luminesc��ncia obtida em presen��a do aumento ou redu����o do miR-363* deu uma forte indica����o da regula����o directa do miR-363* nesses alvos. No entanto, a confirma����o desta interac����o directa foi efectuada atrav��s de ensaios de mutag��nese, nos quais de induziram muta����es na 3���UTR nos locais de liga����o do miRNA, seguidos dos ensaios funcionais como acima descritos. Esta estrat��gia sugere que o TIMP1, inibidor da metaloprotease-9 (MMP-9), �� regulado directamente pelo miR-363*. Adicionalmente, os n��veis de express��o dos alvos directos do miR-363* foram estudados em 17 amostras de aspirados de medula ��ssea de doentes com s��ndromes mielodispl��sicos. Os s��ndromes mielodispl��sicos s��o caracterizados como um grupo heterog��neo de condi����es, que apresentam citopenias (produ����o deficiente de eritr��citos, leuc��citos e/ou megacari��citos) e medula ��ssea displ��stica e hipercelular. A escalonagem dos doentes foi feita de acordo com o sistema de progn��stico IPSS elaborado pela Organiza����o Mundial de Sa��de, e que consiste numa tabela de risco de progress��o de s��ndromes mielodispl��sicos para leucemia miel��ide aguda (LMA) e que agrupa os doentes em baixo risco ��� que compreende os n��veis baixo e interm��dio 1 ��� e em alto risco ��� que compreende os n��veis interm��dio 2 e alto. Dos genes regulados pelo miR-363*, o destacam-se o TIMP1, estando aumentando em doentes com mau progn��stico, e o THBS3 que apresenta um aumento nos doentes com progn��stico interm��dio. Em suma, os estudos realizados permitiram a identifica����o de genes regulados pelo miR-363* e contribuiram para o conhecimento de como o miR-363* contribui para a disfun����o medular, particularmente em s��ndromes mielodispl��sicos, pela desregula����o das propriedades endoteliais.

Effect of polyunsaturated fatty acids (PUFAs) on the proliferation and extracellular matrix mineralization and gene expression of gilthead seabream skeletal cell lines

The aquaculture industry aims at replacing significant amounts of marine fish oil by vegetable oils in fish diet. Dietary lipids have been shown to alter the fatty acid composition of bone compartments, which would impact the local production of factors controlling bone formation. Knowledge on the mechanisms underlying the nutritional regulation of bone metabolism is however scarce in fish. Two in vitro bone-derived cell systems developed from seabream (an important species for aquaculture in the Mediterranean region) vertebra, capable of in vitro mineralization and exhibiting prechondrocyte (VSa13) and pre-osteoblast (VSa16) phenotype, were used to assess the effect of certain polyunsaturated fatty acids (PUFAs; arachidonic (AA), eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids) on cell proliferation, extracellular matrix (ECM) mineralization and gene expression. While all PUFAs promoted morphological changes in both cell lines, VSa16 cell proliferation appeared to be stimulated by PUFAs in a dose dependent manner until 100���M, whereas proliferation of VSa13 cells was impaired at concentrations above 10���M. AA, EPA and DHA inhibited VSa13 ECM mineralization, alone and in combination, while VSa16 ECM mineralization was only inhibited by AA and EPA. DHA had the opposite effect, increasing mineralization almost by 2 fold. When EFAs were combined, DHA apparently compensated for the inhibitory effect of AA and EPA. Expression of marker genes for bone and lipid metabolisms has been investigated by qPCR and shown to be regulated in pre-osteoblasts exposed to individual PUFAs. Our results show that PUFAs are effectors of fish bone cell lines, altering cell morphology, proliferation and mineralization when added to culture medium. This work also demonstrates the suitability of our in vitro cell systems to get insights into mineralization-related effects of PUFAs in vivo and to evaluate the replacement of fish oils by vegetable oil sources in fish feeds.

Aprender a desaprender: (Gogo e Didi, cantata com prel��dio e fugas)

Duas partes substantivas dividem o presente relat��rio: i) o estudo de uma pr��tica teatral específica, sustentada numa pedagogia de natureza gen��tica e consubstanciado na cocria����o de um projeto teatral coletivo; ii) o estudo de um vocabul��rio espec��fico, consubstanciado na reda����o de verbetes a partir da obra de alguns mestres de teatro contempor��neo e da minha pr��pria experimenta����o. Atrav��s da pr��tica teatral baseada no princ��pio geral da autenticidade pude chegar �� compreens��o e vis��o concreta de que o teatro �� uma est��tica, uma t��cnica e uma ��tica ligadas entre si de forma interdependente, que um ator s�� aprende a amar o teatro quando chega a ser capaz de se autorrevelar e que um ator s�� se autorrevela quando �� capaz de se entregar sem reservas �� cocria����o com os outros e com o p��blico. Pelo estudo e reda����o dos verbetes compreendemos que o teatro �� uma arte que acontece sempre no presente e que tanto a alma quanto a est��tica teatral subsistem na capacidade de o ator estar totalmente presente em cena, de tal modo que o inebriamento dionis��aco acontece apenas sob esta condi����o e, sem esta condi����o, ou quando esta condi����o se rompe, quebra-se o equil��brio entre o dionis��aco e a racionalidade apol��nea que acompanha a atua����o.

A resili��ncia e a capacidade de adapta����o �� mudan��a dos professores da licenciatura em Educa����o B��sica face ao tratado Bolonha: constru����o de uma escala de resili��ncia

Com este estudo tenta-se estabelecer uma rela����o entre a resili��ncia e a capacidade de adapta����o �� mudan��a, proporcionada pelo Processo de Bolonha, por parte dos docentes do ensino superior, constituindo-se como principal objetivo desta investiga����o a constru����o de um question��rio que relaciona estes tr��s aspetos. Procura- se ainda percecionar a exist��ncia de diferen��as nesta rela����o entre docentes do setor universit��rio e do polit��cnico. O question��rio constru��do contempla os diversos aspetos da carreira profissional e as diferentes vari��veis de mudan��a que foram exigidas ou a que foram sujeitos os docentes tendo em conta este novo paradigma educacional. Foi aplicado a docentes do ensino superior a lecionar em institui����es p��blicas a n��vel nacional (continente e ilhas), com uma amostra por conveni��ncia (aleat��ria), procurando desenvolver uma pesquisa quantitativa em educa����o. Os dados foram recolhidos atrav��s de plataforma eletr��nica, de forma an��nima, tendo-se obtido 564 respostas, representativas dos dois setores de ensino e de todas as institui����es do pa��s. Recorreu-se a um quadro te��rico de refer��ncia assente numa revis��o da literatura, perspetivado no ��mbito do estudo com enfoque na capacidade de resili��ncia, associada ao modelo transacional e ��s fontes e ��reas de desenvolvimento da mesma (Grotberg, 1985, Wolin & Wolin, 1993, Kumpfer,1999); relacionado com a profiss��o docente foram trabalhados a identidade e o desenvolvimento profissional, compet��ncias, rela����es pessoais e interpessoais e desenvolvimento humano, bem como toda a organiza����o do ensino superior (Gon��alves 1987, 2007, Garcia, 1999, Zarifian, 2001, Ralha-Sim��es & Sim��es, 2002, Le Boterf, 2005, legisla����o relacionada com o Ensino Superior). O estudo encontra-se organizado em cinco cap��tulos: I - enquadramento te��rico, dedicado �� resili��ncia, �� profiss��o docente, ao ensino superior, ao Processo de Bolonha e �� articula����o dos fatores anteriores; II- metodologia da investiga����o e aspetos inerentes, bem como a amostra e os motivos de constru����o do instrumento; III ��� apresenta����o e an��lise dos dados recolhidos, tentando responder ��s quest��es de pesquisa, aos objetivos tra��ados e contributos para a melhoria; IV ��� considera����es finais onde constam as conclus��es do estudo e as possibilidades de futuras perspetivas de investiga����o; V ��� bibliografia. Como principais conclus��es deste estudo salienta-se o facto de as capacidades de resili��ncia dos docentes, nomeadamente a valoriza����o pessoal, que os pr��prios destacam como fator protetor, estarem bem desenvolvidas e interferirem na sua adapta����o ��s altera����es introduzidas ao n��vel pedag��gico, cient��fico e did��tico. Salvaguarda- se contudo que esta adapta����o n��o ocorre ao n��vel da sua carreira profissional e manifesta-se de forma pouco vincada em rela����o �� quest��o da tutoria ou orienta����o tutorial. Por outro lado, sobressai um bom autoconhecimento e a exist��ncia de rela����es intra e interpessoais positivas. No que respeita ��s diferen��as ao n��vel de adaptabilidade entre os docentes dos dois setores de ensino, apesar de existirem, as mesmas n��o s��o significativas.