977 resultados para mixed transfer functions


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Transfer prices are used by the majority of firms worldwide when intermediate products or services are transferred within the same organization. These prices are reported as revenue for the selling entity (division, unit, department etc.) and as cost for the buying entity. Nevertheless, transfer prices lead to many disputes among managers in the same organization as transfer prices influence the performance of their entities. In cross-border transactions, transfer prices can be used by firms to reduce corporate taxes and thus, increase total firm profits. In order to fight against this firms’ practice, tax authorities require firms to establish a transfer pricing system in accordance with OECD1 Transfer Pricing Guidelines.

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RESUMO: As células dendríticas (CDs) são fundamentais na imunomodulação e iniciação de respostas imunes adaptativas, enquanto os ácidos siálicos (Sias) são potenciais imunomoduladores. Estas células expressam níveis elevados da sialiltransferase ST6Gal-1, que transfere Sias para a posição terminal de oligossacáridos. De facto, a maturação de CDs está associada a uma diminuição da sialilação na sua superfície celular. Apesar de ter função biológica desconhecida, a forma solúvel, extracelular de ST6Gal-1 aumenta em cancros e inflamação. Ainda assim, esta foi recentemente identificada como moduladora da hematopoiese. Considerando o importante papel das CDs na iniciação de respostas anticancerígenas, uma ligação entre a sialilação extrínseca induzida por ST6Gal-1 extracelular e o seu papel na modulação de CDs deve ser identificada. Neste trabalho hipotetizou-se que a sialilação α2,6 extrínseca de CDs diminui o seu perfil de maturação mediante ativação por lipopolissacarídeo (LPS). O objetivo principal foi sialilar extrinsecamente em α2,6 CDs da medula óssea de murganhos, avaliando os seus perfis de maturação e de libertação de citocinas, após estimulação com LPS (por Citometria de Fluxo e ELISA, respetivamente). Ao contrário da hipótese, o perfil celular não foi modulado, usando várias abordagens. Por outro lado, a consequência da falta de α2,6 Sias na maturação de CDs foi avaliada analisando: 1) CDs da medula óssea de murganhos tratadas com sialidase, 2) CDs da medula óssea e 3) CDs das vias aéreas, ambas de murganhos deficientes em ST6Gal-1, comparando com a estirpe selvagem. Estes resultados sugerem que a perta total de α2,6 Sias se relaciona com o aumento da expressão do complexo de histocompatibilidade principal de classe II. Apesar de controverso, é provável existirem mecanismos inerentes à ativação por LPS, reduzindo a eficácia de ST6Gal-1 extracelular. Por outro lado, a modificação no perfil de CDs de murganhos deficientes em ST6Gal-1 poderá relacionar-se com uma predisposição para um estado inflamatório severo. Com isto, o trabalho desenvolvido abriu futuras linhas de investigação, nomeadamente explorar outros fatores envolvidos na (de)sialilação α2,6 de CDs, podendo ter impacto em imunoterapia com uso de CDs.--------------------------ABSTRACT: Dendritic cells (DCs) are vital for immunomodulation and the initiation of adaptive immune responses, whereas sialic acids (Sias) are potential immunomodulators. These cells express high levels of sialyltransferase ST6Gal-1, responsible for transferring Sias to the terminal position of oligosaccharide chains. Indeed, DCs’ maturation is associated with decreased cell surface sialylation. Although its biological significance is unknown, the soluble, extracellular form of ST6Gal-1 increases in cancers and inflammation. However, extracellular ST6Gal-1 was recently identified as modulator of hematopoiesis. Considering that DCs play a crucial role in the initiation of a productive anti-cancer immune response, a link between extrinsic sialylation by the extracellular ST6Gal-1 on DC function needs to be investigated. We hypothesize that extrinsic α2,6 sialylation of DCs diminishes their maturation features upon lipopolysaccharide (LPS) stimulation. The main goal was to extrinsically α2,6 sialylate mice bone marrow derived DCs (BMDCs) and to evaluate their maturation and cytokine profiles upon LPS stimulation (by Flow Cytometry and ELISA, respectively). Unlike the hypothesis, we observed that BMDCs’ profile is not modulated, even using several approaches. In contrast, the consequence of lacking cell surface α2,6 Sias in DC maturation was assessed by analysing: 1) sialidase treated BMDCs, 2) BMDCs from mice lacking ST6Gal-1 and 3) DCs from mice airways, comparing wild type with ST6Gal-1 knockout mice. These results suggest that overall lack in α2,6 Sias is related with increased expression of major histocompatibility class II (MHC-II). Although appearing to be controversial findings, other intracellular mechanisms might be occurring upon LPS-induced BMDC activation, probably reducing extracellular ST6Gal-1 effect. In opposite, the modification observed in DC profile of ST6Gal-1 knockout mice might be related to its predisposition to a more severe inflammatory status. With this, the developed work opened future lines of investigation, namely exploring other factors involved in α2,6 (de)sialylation of DC, which might have influence in immunotherapy using DCs.

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IntroductionMixed-species biofilms are involved in a wide variety of infections. We studied the synergistic interactions during dual-species biofilm formation among isolates of Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia.MethodsIsolates were cultured as single-species and all possible combinations of dual-species biofilms.ResultsThe 61 A. baumannii biofilms increased by 26-fold when cultured with S. maltophilia isolates; 62 A. baumannii biofilms increased by 20-fold when cultured with S. maltophilia isolates; and 31 P. aeruginosa biofilms increased by 102-fold when cultured with S. maltophilia 106.ConclusionsSynergy was observed between two isolates, including those that inherently lacked biofilm formation ability.

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Polyhydroxyalkanoates (PHA) production using mixed microbial cultures (MMC) requires a multi-stage process involving the microbial selection of PHA-storing microorganisms, typically operated in sequencing batch reactors (SBR), and an accumulation reactor. Since low-cost renewable feedstocks used as process feedstock are often nitrogen-deficient, nutrient supply in the selection stage is required to allow for microbial growth. In this context, the possibility to uncouple nitrogen supply from carbon feeding within the SBR cycle has been investigated in this study. Moreover, three different COD:N ratios (100:3.79, 100:3.03 and 100:2.43) were tested in three different runs which also allowed the study of COD:N ratio on the SBR performance. For each run, a synthetic mixture of acetic and propionic acids at an overall organic load rate of 8.5 gCOD L-1 d-1 was used as carbon feedstock, whereas ammonium sulfate was the nitrogen source in a lab-scale sequence batch reactor (SBR) with 1 L of working volume. Besides, a sludge retention time (SRT) of 1 d was used as well as a 6 h cycle length. The uncoupled feeding strategy significantly enhanced the selective pressure towards PHA-storing microorganisms, resulting in a two-fold increase in the PHA production (up to about 1.3 gCOD L-1). A high storage response was observed for the two runs with the COD:N ratios (gCOD:gN) of 100:3.79 and 100:3.03, whereas the lowest investigated nitrogen load resulted in very poor performance in terms of polymer production. In fact, strong nitrogen limitation caused fungi to grow and a very poor storage ability by microorganisms that thrived in those conditions. The COD:N ratio also affected the polymer composition, indeed the produced poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) showed a variable HV content (1-20 %, w/w) among the three runs, lessening as the COD:N increased. This clearly suggests the possibility to use the COD:N ratio as a tool for tuning polymer properties regardless the composition of the feedstock.

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Exosomes are small membrane vesicles secreted by most cell types, either normal or malignant and are found in most body fluids such as saliva, plasma and breast milk. In the past decade, the interest in these vesicles has been growing more and more since it was found that besides their beneficial functions such as the removal of cellular debris and unnecessary proteins during cell maturation process, they can also interact with other cells and transfer information between them, thus helping diseases like cancer to progress. The present work intended to use gold nanoparticles as vehicles for gene silencing in an attempt to reduce the tumor-derived exosome secretion, regulated by Rab27a protein, and also aimed to compare the exosome secretion between two breast cell lines, MCF7 and MDA. Changes in RAB27A gene expression were measured by Real-time Quantitative PCR and it was revealed a decreased in RAB27A gene expression, as expected. Exosomes were isolated and purified by two different methods, ultracentrifugation and the commercial kit ExoQuick™ Solution, and further characterized using Western Blot analysis. ExoQuick™ Solution was proven to be the most efficient method for exosome isolation and it was revealed that MDA cells secrete more exosomes. Furthermore, the isolated MCF7-derived exosomes were placed together with a normal bronchial/tracheal epithelial cell line (BTEC) for an additional assay, which aimed to observe the uptake of exosomes by other cells and the exosomes’ capability of promoting cell-cell communication. This observation was made based on alterations in the expression levels of c-Myc and miR-21 genes and the fact that they both have an increased expression in BTEC cells incubated with tumor-derived exosomes when compared to control cells (without incubation with the exosomes) lead us to the conclusion that the exosome uptake and exchange of information between the exosomes and the normal cells did occurred.

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Polyhydroxyalkanoates (PHAs) are natural biologically synthesized polymers that have been the subject of much interest in the last decades due to their biodegradability. Thus far, its microbial production is associated with high operational costs, which increases PHA prices and limits its marketability. To address this situation, this thesis’ work proposes the utilization of photosynthetic mixed cultures (PMC) as a new PHA production system that may lead to a reduction in operational costs. In fact, the operational strategies developed in this work led to the selection of PHA accumulating PMCs that, unlike the traditional mixed microbial cultures, do not require aeration, thus permitting savings in this significant operational cost. In particular, the first PHA accumulating PMC tested in this work was selected under non-aerated illuminated conditions in a feast and famine regime, being obtained a consortium of bacteria and algae, where photosynthetic bacteria accumulated PHA during the feast phase and consumed it for growth during the famine phase, using the oxygen produced by algae. In this symbiotic system, a maximum PHA content of 20% cell dry weight (cdw) was reached, proving for the first time, the capacity of a PMC to accumulate PHA. During adaptation to dark/light alternating conditions, the culture decreased its algae content but maintained its viability, achieving a PHA content of 30% cdw. Also, the PMC was found to be able to utilize different volatile fatty acids for PHA production, accumulating up to 20% cdw of a PHA co-polymer composed of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (HV) monomers. Finally, a new selective approach for the enrichment of PMCs in PHA accumulating bacteria was tested. Instead of imposing a feast and famine regime, a permanent feast regime was used, thus selecting a PMC that was capable of simultaneously growing and accumulating PHA, being attained a maximum PHA content of 60% cdw, the highest value reported for a PMC thus far. The results presented in this thesis prospect the utilization of cheap, VFA-rich fermented wastes as substrates for PHA production, which combined with this new photosynthetic technology opens up the possibility for direct sunlight illumination, leading to a more cost-effective and environmentally sustainable PHA production process.

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RESUMO: Os glicoconjugados que decoram a superfície celular e os lípidos e proteínas secretados ocupam o ponto de encontro onde normalmente ocorrem interacções críticas homólogas (hospedeiro-hospedeiro) e heterólogas (hospedeiro-patogénio). Apesar de ser largamente aceite que os glicanos são parte integrante do processo de imunidade, continua a não ser claro qual o papel que os glicanos, em toda a sua diversidade, tomam no quadro geral da imunidade. Os glicanos, que são frequentemente terminados por resíduos de ácido siálico, podem ser alterados por factores externos, tais como patogénios, ou por acontecimentos fisiológicos celulares específicos. Normalmente em posição terminal, as glico-estruturas que contêm ácido siálico assumem um papel fundamental numa quantidade substancial de receptores imunes envolvidos na adesividade e tráfico celular, tal como as Selectinas e as Siglecs, das quais se sabe apresentarem uma relevante função imune. À altura do início desta tese, era sabido que os ácidos siálicos expressos à superfície das células poderiam modular mecanismos importantes nas respostas imunes adaptativas. Considerando a posição de charneira que as células dendríticas (DCs) ocupam na transição da resposta imune inata para a adaptativa, antecipámos que os ácidos siálicos poderiam também modular mecanismos relevantes nas DCs humanas. As DCs têm uma função muito relevante na verificação e captura antigénica, migração para os gânglios linfáticos e apresentação antigénica aos linfócitos, uma sequência de funções que conduz, em ultima instância, à indução da resposta inata adaptativa. Considerando estas premissas, a nossa hipótese principal foi que os ácidos siálicos podem influenciar funções relevantes das DCs, tais como captura de antigénios, maturação, migração para os gânglios linfáticos e apresentação antigénica às células Para testar esta hipótese, dividimos o trabalho em quatro partes: 1) Analisámos os glicanos sialilados de superfície, expressos durante a diferenciação de monócitos humanos em DCs (moDCs). Os nossos dados mostraram que a expressão dos glicanos com ligações em O (O-glicanos) e sialilados em α2,3, assim como glicanos com ligações em N (N-glicanos) sialilados em α2,6 e α2,3 aumentou durante o processo de diferenciação das moDCs. Contribuindo para esta nova configuração glicosídica, três sialiltransferases (STs) poderão estar envolvidas: a ST6Gal-1 correlaciona-se com a expressão aumentada de N-glicanos sialilados em α2,6; a ST3Gal-1 contribui para a sialilação em α2,3 de O-glicanos, em especial de antigénios T; e a ST3Gal-4 poderá ser responsável pelo aumento de N-glicanos sialilados em α2,3. Após estímulo e consequente maturação das moDCs, ambos os níveis de expressão génica de ST6Gal-1 e ST3Gal-4 são negativamente modificados sendo, também, que a expressão de ST3Gal-1 varia consoante o estímulo. 2) Estudámos posteriormente as consequências da modulação dos ácidos siálicos de superfície nas funções das DCs. Observámos que a remoção dos ácidos siálicos de superfície diminui significativamente a capacidade de macropinocitose e endocitose mediada por receptores nas moDCs. Em contrapartida, o tratamento com sialidase aumentou significativamente a capacidade das moDCs para fagocitar Escherichia coli. Determinou-se também que este mecanismo requer a existência de ácido siálico presente nas E. coli indicando um mecanismo de interacção hospedeiro-patogénio dependente de ácido siálico em ambas as partes envolvidas. As moDCs tratadas com sialidase também apresentam um nível superior de expressão de moléculas de MHC e moléculas co-estimulatórias, sugerindo um fenótipo celular mais maduro. Recorrendo ao modelo de ratinho, utilizaram-se DCs derivadas de células da medula (BMDCs) de ratinhos deficientes em ST3Gal-1 e ST6Gal-1. Estes ensaios revelaram que quer a endocitose quer a maturação são influenciadas por modificações 37 nos glicanos sialilados em α2,3 ou α2,6. A detecção e quantificação de proteínas Nglicosiladas e sialiladas em α2,6 apontou para um potencial envolvimento de integrinas β2 nestes mecanismos. 3) O efeito da sialilação em α2,6 na migração das DCs para os gânglios linfáticos foi também analisado. Observámos que BMDCs deficientes para ST6Gal-1 apresentam uma redução de cerca de 50% nos níveis de migração das DCs para os gânglios linfáticos, tal como aferido em ensaios de inflamação in situ e estudos de transferência adoptiva de células. Uma redução dos níveis deste tipo de migração foi também observada quando BMDCs nativas foram transferidas para ratinhos receptores deficientes em ST6Gal-1. São, contudo, necessários mais ensaios de forma a identificar as moléculas envolvidas neste processo. 4) Por último, analisámos o impacto da sialilação na estimulação antigénica das DCs às células T. Assim, concluiu-se que moDCs tratadas com sialidase apresentam um nível de expressão superior de IL-12, TNF-ɑ, IL-6 e IL-10, e activação do factor de transcrição nuclear kappa B (NF-κB). As DCs tratadas com sialidase induziram uma maior proliferação nas células T, com expressão correspondente de interferão-γ. Este dado sugere que a remoção de ácidos siálicos de superfície contribui para o desenvolvimento de uma resposta pro-inflamatória do tipo 1 por células T auxiliares (resposta Th1). Considerando estes dados no seu todo, concluímos que o ácido siálico tem um papel marcante nas funções imunes das DCs. Alterações à concentração de ácido siálico à superfície das células podem alterar a endocitose/fagocitose, maturação, migração para os tecidos e gânglios linfáticos e capacidade estimulatória para com as células T. Complementando estes dados, as ligações glicosídicas de ácidos siálicos criados por ST6Gal-1 e ST3Gal-1 são funcionalmente relevantes. A modulação programada da sialilação do glicocálice, mediada por sialidases individuais ou sialiltransferases é uma possibilidade aceitável para a melhoria da fagocitose por DCs e da sua potência imunológica. Este facto tem um significado particular para imunoterapias baseadas em DCs, podendo provar-se decisivo para a sua eficiência e aplicabilidade num futuro muito próximo.-------------------------------ABSTRACT: Glycans decorating cell surface and secreted proteins and lipids occupy the junction where critical host–host and host-pathogen interactions occur. In spite of the wide acceptance that glycans are centrally implicated in immunity, exactly how glycans and their variety and variability contribute to the overall immune response remains poorly defined. Glycans, frequently terminated by sialic acid residues, may be modified by external factors such as pathogens or upon specific physiological cellular events. The terminal, privileged positions of sialic acid-modified structures makes them key, fundamental determinants for a number of immune receptors with known involvement in cellular adhesiveness and cell trafficking, such as Selectins and Siglecs, with known relevant immune functions. At the time this thesis was initiated, it was established that sialic acids expressed at cell surface could modulate important mechanisms of the adaptive immune responses. Given the key role of dendritic cells (DCs) in the transition from innate to the adaptive immune responses, we anticipated that sialic acids could also modulate important mechanisms of human DCs. DCs have a relevant role in antigen screening and uptake, migration to lymph nodes and antigen presentation to lymphocytes, ultimately triggering the adaptive immune response. Therefore, our primary hypothesis was that sialic acids may modulate DC functions, such as antigen uptake, maturation, homing to lymph nodes and antigen presentation to T cells. To test this hypothesis, we divided our work in four parts. 1) Surface sialylated glycans expressed during differentiation from human monocytes to DCs (moDCs) were analyzed. Our data showed that α2,3-sialylated O-glycans and α2,6- and α2,3-sialylated N-glycans expression increased during moDC differentiation. Three main sialyltransferases (STs) are committed with this new glycan configuration: ST6Gal- 1 correlates with the increased expression of α2,6-sialylated N-glycans; ST3Gal-1 32 contributes for the α2,3-sialylation of O-glycans, especially T antigens; and ST3Gal-4 may contribute for the increased α2,3-sialylated N-glycans. Upon moDC maturation, ST6Gal-1 and ST3Gal-4 are downregulated and ST3Gal-1 is altered in a stimulus dependent manner. 2) We subsequently analyzed the consequences of the modulation of cell surface sialic acids in DC functions. We observed that removing surface sialic acid by sialidase significantly decreased the capacity of moDCs to micropinocytose and receptormediated endocytose. In contrast, treatment with a sialidase significantly improved the capacity of moDCs to phagocytose Escherichia coli. The improved phagocytosis mechanism required E. coli sialic acids, indicating a mechanism of host–pathogen interaction dependent on sialic acid moieties. Sialidase-treated moDCs have increased expression of MHC and co-stimulatory molecules, suggesting a more mature phenotype. Experiments using mouse bone marrow-derived DCs (BMDCs) from ST3Gal-1-/- and ST6Gal-1-/- strains indicated that endocytosis and maturation are influenced by changes in either α2,3 or α2,6-sialylated glycans. The analysis of α2,6-sialylated, N-glycosylated proteins, strongly suggested the potential involvement of β2 integrins, underlying these mechanisms. 3) The effect of α2,6-sialylation in DC homing to lymph nodes was also analyzed. We observed that BMDCs deficient for ST6Gal-1 have an almost 50% reduction in DC homing, as assayed by in situ inflammation and adoptive transfer studies. A reduction in DC homing was also observed when wild type BMDCs were transferred into ST6Gal-1-/- recipient mice. Further investigations are necessary to identify the molecules involved in this process. 4) Finally, we also analyzed the impact of sialylation on DCs ability to prime T cells. Sialidase-treated moDCs show increased gene expression of IL-12, TNF-α, IL-6 and IL- 10 cytokines, and activation of the transcription factor nuclear factor-κB. Sialidase33 treated DCs induced a higher proliferative response of T cells with concomitant higher expression of interferon-γ, suggesting that the clearance of cell surface sialic acids contributes to the development of a T helper type 1 proinflammatory response. Together, our data strongly support sialic acid’s relevance in DC immune functions. Alterations of cell surface sialic acid content can alter the endocytosis/phagocytosis, maturation, migration/homing and the ability for T cell priming in human DCs. Moreover, sialic acid linkages created by ST6Gal-1 and ST3Gal-1 are functionally relevant. The engineering of cell surface sialylation, mediated by individual sialidases or sialyltransferases is a likely possibility to fine tune DC phagocytosis and immunological potency, with particular significance to DC-based therapies.

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The present work project investigates the implications of design thinking on an interbusiness collaborative project, unveiling both the benefits and fragilities that derive from the use of such methodology within the mentioned context. The study is organized in two parts. The first one starts with a literature review on the two relevant frames of reference – design thinking and business collaboration. It proceeds to the creation of a conceptual framework to assess the potential value of the design-based approach. The second part focuses on the practical application of to the newly developed instrument to the inTRAIN project – R&D for railway interiors.

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Tissue-to-tissue interfaces are commonly present in all tissues exhibiting structural, biological and chemical gradients serving a wide range of physiological functions. These interfaces are responsible for mediation of load transfer between two adjacent tissues. They are also important structures in sustaining the cellular communications to retain tissueâ s functional integration and homeostasis. [1] All cells have the capacity to sense and respond to physical and chemical stimulus and when cultured in three-dimensional (3D) environments they tend to perform their function better than in two-dimensional (2D) environments. Spatial and temporal 3D gradient hydrogels better resemble the natural environment of cells in mimicking their extracellular matrix. [2] In this study we hypothesize that differential functional properties can be engineered by modulation of macromolecule gradients in a cell seeded threedimensional hydrogel system. Specifically, differential paracrine secretory profiles can be engineered using human Bone Marrow Stem Cells (hBMSCâ s). Hence, the specific objectives of this study are to: assemble the macromolecular gradient hydrogels to evaluate the suitablity for hBMSCâ s encapsulation by cellular viability and biofunctionality by assessing the paracrine secretion of hBMSCâ s over time. The gradient hydrogels solutions were prepared by blend of macromolecules in one solution such as hyaluronic (HA) acid and collagen (Col) at different ratios. The gradient hydrogels were fabricated into cylindrical silicon moulds with higher ratio solutions assembled at the bottom of the mould and adding the two solutions consecutively on top of each other. The labelling of the macromolecules was performed to confirm the gradient through fluorescence microscopy. Additionally, AFM was conducted to assess the gradient hydrogels stiffness. Gradient hydrogels characterization was performed by HA and Col degradation assay, degree of crosslinking and stability. hBMSCâ s at P3 were encapsulated into each batch solution at 106 cells/ml solution and gradient hydrogels were produced as previously described. The hBMSCâ s were observed under confocal microscopy to assess viability by Live/Dead® staining. Cellular behaviour concerning proliferation and matrix deposition was also performed. Secretory cytokine measurement for pro-inflammatory and angiogenesis factors was carried out using ELISA. At genomic level, qPCR was carried out. The 3D gradient hydrogels platform made of different macromolecules showed to be a suitable environment for hBMSCâ s. The hBMSCâ s gradient hydrogels supported high cell survival and exhibited biofunctionality. Besides, the 3D gradient hydrogels demonstrated differentially secretion of pro-inflammatory and angiogenic factors by the encapsulated hBMSCâ s. References: 1. Mikos, AG. et al., Engineering complex tissues. Tissue Engineering 12,3307, 2006 2. Phillips, JE. et al., Proc Natl Acad Sci USA, 26:12170-5, 2008

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\The idea that social processes develop in a cyclical manner is somewhat like a `Lorelei'. Researchers are lured to it because of its theoretical promise, only to become entangled in (if not wrecked by) messy problems of empirical inference. The reasoning leading to hypotheses of some kind of cycle is often elegant enough, yet the data from repeated observations rarely display the supposed cyclical pattern. (...) In addition, various `schools' seem to exist which frequently arrive at di erent conclusions on the basis of the same data." (van der Eijk and Weber 1987:271). Much of the empirical controversies around these issues arise because of three distinct problems: the coexistence of cycles of di erent periodicities, the possibility of transient cycles and the existence of cycles without xed periodicity. In some cases, there are no reasons to expect any of these phenomena to be relevant. Seasonality caused by Christmas is one such example (Wen 2002). In such cases, researchers mostly rely on spectral analysis and Auto-Regressive Moving-Average (ARMA) models to estimate the periodicity of cycles.1 However, and this is particularly true in social sciences, sometimes there are good theoretical reasons to expect irregular cycles. In such cases, \the identi cation of periodic movement in something like the vote is a daunting task all by itself. When a pendulum swings with an irregular beat (frequency), and the extent of the swing (amplitude) is not constant, mathematical functions like sine-waves are of no use."(Lebo and Norpoth 2007:73) In the past, this di culty has led to two di erent approaches. On the one hand, some researchers dismissed these methods altogether, relying on informal alternatives that do not meet rigorous standards of statistical inference. Goldstein (1985 and 1988), studying the severity of Great power wars is one such example. On the other hand, there are authors who transfer the assumptions of spectral analysis (and ARMA models) into fundamental assumptions about the nature of social phenomena. This type of argument was produced by Beck (1991) who, in a reply to Goldstein (1988), claimed that only \ xed period models are meaningful models of cyclic phenomena".We argue that wavelet analysis|a mathematical framework developed in the mid-1980s (Grossman and Morlet 1984; Goupillaud et al. 1984) | is a very viable alternative to study cycles in political time-series. It has the advantage of staying close to the frequency domain approach of spectral analysis while addressing its main limitations. Its principal contribution comes from estimating the spectral characteristics of a time-series as a function of time, thus revealing how its di erent periodic components may change over time. The rest of article proceeds as follows. In the section \Time-frequency Analysis", we study in some detail the continuous wavelet transform and compare its time-frequency properties with the more standard tool for that purpose, the windowed Fourier transform. In the section \The British Political Pendulum", we apply wavelet analysis to essentially the same data analyzed by Lebo and Norpoth (2007) and Merrill, Grofman and Brunell (2011) and try to provide a more nuanced answer to the same question discussed by these authors: do British electoral politics exhibit cycles? Finally, in the last section, we present a concise list of future directions.

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This work presents a model and a heuristic to solve the non-emergency patients transport (NEPT) service issues given the new rules recently established in Portugal. The model follows the same principle of the Team Orienteering Problem by selecting the patients to be included in the routes attending the maximum reduction in costs when compared with individual transportation. This model establishes the best sets of patients to be transported together. The model was implemented in AMPL and a compact formulation was solved using NEOS Server. A heuristic procedure based on iteratively solving problems with one vehicle was presented, and this heuristic provides good results in terms of accuracy and computation time.

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COST (European Co-operation in the field of scientific and technical research) is the longest running framework for research co-operation iri Europe, having been established in 1971 by a Ministerial Conference attended by Ministers for Science and Technology from 19 countries. Today COST is used by the scientific communities of 35 European countries to cooperate in exchanging knowledge and technology developed within research projects supported by national or European funds. The main objective of COST is to contribute to the realization of the European Research Área (ERA) anticipating and complementing the activities of the' Framework Programmes, constituting a "bridge" towards the scientific communities of emerging countries, increasing the mobility of researchers across Europe and fostering the establishment of "Networks of Excelience". Another essential objective is the knowledge transfer between the scientific soc'iety and industry. It is widely acknowledged that European scientific performance in relation to investment in science is excellent but technological and commercial performance has steadily worsened. The present paper discusses how the COST Action's instruments, from training schools to short scientific missions and workshops have been used within The COST ACTION FP11O1 Assessment, Reinforcement and Monitoring of Timber Structures to achieve such objectives.

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This study presents an experimental program to assess the tensile strain distribution along prestressed carbon fiber reinforced polymer (CFRP) reinforcement flexurally applied on the tensile surface of RC beams according to near surface mounted (NSM) technique. Moreover, the current study aims to propose an analytical formulation, with a design framework, for the prediction of distribution of CFRP tensile strain and bond shear stress and, additionally, the prestress transfer length. After demonstration the good predictive performance of the proposed analytical approach, parametric studies were carried out to analytically evaluate the influence of the main material properties, and CFRP and groove cross section on the distribution of the CFRP tensile strain and bond shear stress, and on the prestress transfer length. The proposed analytical approach can also predict the evolution of the prestress transfer length during the curing time of the adhesive by considering the variation of its elasticity modulus during this period.

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Thermal degradation upon melting is one of the major drawbacks reported for polyhydroxyalkanoates (PHA). However, the role of residues originating from the fermentation and the extraction steps on the thermal stability of this class of biopolymers still needs to be clarified. In the particular case of PHA produced from mixed microbial cultures (MMC), this topic is even less documented in the literature. Here, two polyhydroxy(butyrate-co-valerate) (PHBV) produced from MMC enriched in PHA accumulating organisms and fed with cheese whey were studied. A micro extrusion line is used to produce filaments and assess the processability and the degradation of processed PHBV. The prototype micro extrusion line allows for studying grams of materials. The two PHBV contain 18 mol% HV. PHBV was recovered with 11 wt% residues, and further submitted to a purification procedure resulting in a second biopolyester containing less than 2 wt% impurities. The thermorheological characterization of the two PHBV is first presented, together with their semicrystalline properties. Then the processing windows of the two biopolyesters are presented. Finally, the properties of extruded filaments are reported and the thermomechanical degradation of PHBV is extensively studied. The structure was assessed by wide angle X-ray diffraction, mechanical and rheological properties are reported, thermal properties are studied with differential scanning calorimetry and thermogravimetric analysis, whereas Fourier Transform Infrared spectroscopy was used to assess the impact of the extrusion on PHBV chemical structure. All results obtained with the two PHBV are compared to assess the effects of residues on both PHBV processability and degradation.

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Universities are increasingly institutionalizing activities related to technology transfer and one of the main institutional mechanisms that has emerged is the “technology transfer unit” (TTU). Many of them are focusing their activities on the management of the university intellectual property. Studies have investigated factors that seem to affect their performance, but few have looked in detail at internal procedures and techniques that are used in their processes related to technology evaluation and licensing. The aim of this paper is to provide a comprehensive overview of some of the several steps that comprises the processes regarding technology evaluation and licensing, providing an analysis of the critical issues that affect each step of the process. A review of the literature was made, complemented with interviews to seven university TTUs, which was used as a check and a complement to the literature review and as way of perceiving from an insider perspective, the problems and issues that this paper wants to emphasize and to state clearly.