11 resultados para polimeri side-chain push-pull-push ottica non lineare (NLO) Third Harmonic Generation (THG)


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Dissertation presented to obtain a Ph.D. degree in Biology, speciality Microbiology, by Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Dissertação apresentada para obtenção do Grau de Doutor em Conservação e Restauro, especialidade de Ciências da Conservação, pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Dissertation presented to obtain the Doutoramento (Ph.D.) degree in Biochemistry at the Instituto de Tecnologia Qu mica e Biol ogica da Universidade Nova de Lisboa

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The bacterium Geobacter sulfurreducens (Gs) is capable of oxidizing a large variety of compounds relaying electrons out of the cytoplasm and across the membrane in a process designated as extracellular electron transfer. The Gs genome was fully sequenced and a family composed by five periplasmic triheme cytochromes c7 (designated PpcA-E) was identified. These cytochromes play an important role in the reduction of extracellular acceptors. They contain approximately 70 amino acids, three heme groups with bis-histidinyl axial coordination, and share between 57 and 77% sequence identity. The triheme cytochrome PpcA is highly abundant in Gs and is most likely the reservoir of electrons destined for outer surface. In addition to its role in electron transfer pathways this protein can perform e-/H+ energy transduction, a process that is disrupted when the strictly conserved aromatic residue phenylalanine 15 is replaced by a leucine (PpcAF15L). This Thesis focuses on the expression, purification and characterization of these proteins using Nuclear Magnetic Resonance and ultraviolet-visible spectroscopy. The orientations of the heme axial histidine ring planes and the orientation of the heme magnetic axis were determined for each Gs triheme cytochrome. The comparison of the orientations obtained in solution with the crystal structures available showed significant differences. The results obtained provide the paramagnetic constraints to include in the future refinement of the solution structure in the oxidized state. In this work was also determined the solution structure and the pH-dependent conformational changes of the PpcAF15L allowing infer the structural origin for e-/H+ energy transduction mechanism as shown by PpcA. Finally, the backbone and side chain NH signals of PpcA were used to map interactions between this protein and the putative redox partner 9,10-anthraquinone-2,6-disulfonate (AQDS). In this work a molecular interaction was identified for the first time between PpcA and AQDS, constituting the first step toward the rationalization of the Gs respiratory chain.

Relevância:

40.00% 40.00%

Publicador:

Resumo:

Field Lab in Entrepreneurial Innovative Ventures

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Dissertação para obtenção do Grau de Doutor em Engenharia Civil,Especialidade Estruturas

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Dissertation presented to obtain the PhD degree in Electrical and Computer Engineering - Electronics

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The relative attractiveness of cities as places to live determines population movements in or out of them. Understanding the appealing features of a city is fundamental to local governments, particularly for cities facing population decline. Pull and push attributes of cities can include economic aspects, the availability of amenities and psychological constructs, initiating a discussion around which factors are more relevant in explaining migration. However, a pull–push approach has been underexplored in studies of shrinking cities. In the present study, we contribute to the discussion by identifying pull and push factors in Portuguese shrinking cities. Data were collected using a face-to-face questionnaire survey of 701 residents in four shrinking cities: Oporto, Barreiro, Peso da Régua and Moura. Factor analysis and automatic linear modelling were used to analyse the data. Our results support previous findings that the economic activity of a city is the most relevant feature for retaining residents. However, other characteristics specific to each city, especially those related to heritage and natural beauty, are also shown to influence a city’s attractiveness as a place to live. The cause of population shrinkage is also found to influence residents’ assessments of the pull and push attributes of each city. Furthermore, the results show the relevance of social ties and of place attachment to inhabitants’ intention to continue living in their city of residence.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In this paper, we investigate whether being part of the euro area influences the conditional probability of going through a sudden stop or a bonanza of capital flows. Our sample period is from 1995 until 2014. We identify these two phenomena and we evaluate which push and pull factors help predict the conditional probability of experiencing one of them. We find that most countries had significant capital inflows until 2008 and that there were more sudden stops during the recent financial crisis than in any other moment in our sample. The factors that better help forecast the conditional probability of a sudden stop are global uncertainty (represented by the push factor “Volatility Index”), and the domestic economic activity (pull factors “GDP growth” and “consumer confidence”). An indicator of country risk (pull factor “change in credit rating”) is the most significant one for predicting bonanzas. Ultimately, we find no evidence that being part of the euro area influences the conditional probability of going through a sudden stop or a bonanza.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

This work project aims to demonstrate how to design and develop an innovative concept of video streaming app. The project combines technology push and market pull theories into developing a product that is more suitable for the customer needs, with the particularity that there is no other way of seeing any place in the world, live and ondemand. An analysis on the bigger influencers in terms of design-thinking and new product development, as Tim Brown or Paul Trott, lead to a better understanding on how There App should evolve, keeping in mind the customer desires and technical features.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In the increasingly competitive market of higher education introduced by the Bologna Declaration, understanding the decision-making of master in management students is at the center of institutional management and marketing efforts on its mission to attract prospective students in a less costly, more efficient manner. The means-end chain approach, applied to the choice of a Portuguese institution in which to pursue a master in management, points to the position in rankings and to the non-specificity of the program as the most important attributes. Additionally, results show that students with distinct demographic, household, or background characteristics choose in significantly different manners.