6,841 research outputs found
Municípios em Portugal
Enquadramento da realidade municipal portuguesa, numa ótica jurídica.info:eu-repo/semantics/publishedVersio
Understanding the mobile hospitality services adoption: A UTAUT2 and perceived value application in a hotel consumer context
Com o intuito de atrair os novos utilizadores de tecnologias moveis, algumas cadeias hoteleiras começaram a lançar Serviços Moveis Hoteleiros (SMH). Os SMH, referem-se ao uso de telemóveis como ferramentas de acesso e compra de serviços hoteleiros. Através de aplicações para telemóvel, os hóspedes podem ter acesso a serviços como reserva de quartos, check-in/out, concierge, serviço de quartos e de limpeza. OS SMH permitem aos hóspedes acederem aos serviços dos hotéis de forma rápida, onde e quando quiserem, apenas precisando de uma ligação à internet para desempenharem essas tarefas. Sendo que, a aceitação dos SMH pelos utilizadores é crucial para o sucesso da implementação destes sistemas, é imperioso para os profissionais e académicos, compreenderem os factores que influenciam a adopção dos SMH. Foi então desenvolvido um modelo conceptual que combina a extensão da teoria unificada de aceitação e uso da tecnologia (UTAUT2) com o factor de valor percepcionado, com vista a explicar a intenção de uso e recomendação dos SMH. Para testar o modelo conceitual foram reunidos dados de 348 casos validados, e observou-se que o modelo explica 62 por cento da variação na intenção de uso dos SMH, e 51 por cento da variação na recomendação. Os resultados suportam que a expectativa de performance, expectativa de esforço, condições facilitadoras e o factor valor percepcionado explicam a intenção de uso dos SMH. Por sua vez, a recomendação dos SMH é influenciada pela intenção de uso e pelo factor de valor percepcionadas. As implicações teórico-práticas dos nossos resultados são discutidas.In order to attract new consumers, stay competitive, and increase revenues, some hospitality corporations have started to launch Mobile Hospitality Services (MHS). MHS refer to using cell phones as a tool to access, request, and buy services related to hotels. For this reason we developed a conceptual model that combines the extension of unified theory of acceptance and use of technology (UTAUT2) with perceived value to explain behavior intention and recommendation of MHS. To test the conceptual model we collected data from 348 cases, and found that the model explains 62 percent of the variation in behavior intention to use MHS, and 51 percent of the variation in recommendation. Our findings support the belief that performance expectancy, effort expectancy, facilitating conditions, and perceived value explain behavior intention of MHS. Recommendation of MHS is explained by behavioral intention and perceived value. Theoretical and managerial implications of our results are discussed
Bond behaviour of NSM CFRP-concrete systems: adhesive and CFRP cross-section influences
Near Surface Mounted (NSM) strengthening technique has been used in a sustainable way for retrofitting existing structures. This technique, which utilizes CFRP laminates inserted in the concrete cover, has been used due to the several advantages when compared with the technique based on the application of these reinforcing materials on the concrete surface (EBR technique). Although several studies have been developed on this topic in the recent past, open issues still deserve research, such as the influence of the adhesive type on the performance of the NSM-CFRP system. The present work details an experimental program carried out in order to assess the effect of using three adhesives with distinct mechanical properties on the bond behavior of the NSM-CFRP system, through direct pullout tests (DPT). Thus, the following variables were considered in the present study: (i) the type of adhesive; (ii) the cross section of the laminate; and, (iii) the bond length. The experimental pullout force-slip responses were obtained and digital image correlation (DIC) was used for obtaining additional information about the bond mechanisms developed. In general, two of the three adhesives, with similar mechanical characteristics, provided essentially similar bond behavior, with high level of effectiveness, whereas the third adhesive, which had a much lower elastic modulus than the other two, provided the lowest effectiveness in terms of the investigated parameters.This work was supported by FEDER funds through the Operational Program for Competitiveness Factors –
COMPETE and National Funds through FCT (Portuguese Foundation for Science and Technology) under the
projects CutInDur FCOMP-01-0124-FEDER-014811 (FCT PTDC/ECM/112396/2009), FRPreDur FCOMP-01-
0124-FEDER-028865 (FCT PTDC/ECM-EST/2424/2012), FRPLongDur POCI-01-0145-FEDER-016900 (FCT
PTDC/ECM-EST/1282/2014) and partly financed by the project POCI-01-0145-FEDER-007633.
Durability of bond in NSM CFRP-concrete systems under different environmental conditions
This paper addresses the durability of bond between concrete and carbon fibre reinforced polymer (CFRP) strips installed according to the near-surface mounted (NSM) technique (NSM CFRP-concrete systems) under the effects of two main groups of environmental conditions: (i) laboratory-based ageing conditions; (ii) real outdoor ageing conditions. The bond degradation was evaluated by carrying out direct pullout tests on aged specimens that were previously subjected to distinct environmental conditions for different periods of exposure. Moreover, the degradation of the mechanical properties of the involved materials was investigated. The digital image correlation (DIC) method was used to document the evolution of the deformation fields at the surface over the whole region of interest consisting of concrete and epoxy adhesive at the ligament region. This information supported the discussion about the evolution of the bond resistant mechanism developed in NSM CFRP-concrete specimens during testing, as well as the assessment of the bond quality of the system. In general, the results obtained from the durability tests conducted have shown that the different exposure environments, which may be considered as quite severe, did not result in significant damage on NSM CFRP-concrete system. The maximum decrease of about 12% on bond strength was obtained for real outdoor environments. Conversely, a maximum increase of 8% on bond strength was obtained on the specimens exposed to the temperature cycles between –15 °C and +60 °C. DIC allowed to document the stress transfer mechanisms established between the CFRP and the concrete substrate, revealing the crack patterns and the influence widths of the CFRP reinforcement strips, which were shown to be important for avoiding group effect when using multiple parallel strengthening CFRP strips.FEDER funds through the Operational Program for Competitiveness Factors - COMPETE and National Funds through FCT - Portuguese Foundation for Science and Technology under the projects CutInDur FCOMP-01-0124-FEDER-014811 (PTDC/ECM/112396/2009), FRPLongDur POCI-01-0145-FEDER-016900 (PTDC/ECM-EST/1282/2014) and partly financed by the project POCI-01-0145-FEDER-007633. The authors also like to thank all the companies that have been involved supporting and contributing for the development of this study, mainly: S&P Clever Reinforcement Ibérica Lda., Artecanter - Indústria de Transformação de Granitos, Lda., Vialam – Indústrias Metalúrgicas e Metalomecânicas, Lda.info:eu-repo/semantics/publishedVersio
Comportamento da aderência de sistema de reforço NSM-CFRP na presença de diferentes tipos de adesivos
No contexto atual, o reforço de estruturas de betão armado assume uma importância cada vez maior devido a diversos fatores. A técnica de reforço de estruturas de betão armado que utiliza laminados de CFRP inseridos no betão de recobrimento (designada por NSM – Near Surface Mounted na literatura inglesa) tem vindo a ser alvo de vários estudos dadas as suas potencialidades. No entanto, o estudo da influência do tipo de adesivo na aplicação desta técnica apresenta conhecimento limitado. É sobretudo neste aspeto que o presente estudo incide. Foi desenvolvido um programa experimental constituído por ensaios de arranque direto com o objetivo de estudar o comportamento da ligação entre os laminados de CFRP e o betão de sistemas NSM-CFRP, utilizando três variáveis de estudo: (i) tipo de adesivo; (ii) comprimento de ancoragem; e, (iii) secção transversal do laminado de CFRP. Durante a realização dos ensaios, sob controlo de deslocamento, foi monitorizada a força de arranque bem como o deslizamento no final da zona carregada. Foi também utilizada a Correlação Digital de Imagem (DIC) como complemento para avaliação do comportamento da ligação. De uma forma geral, dois dos adesivos proporcionaram padrões de comportamento da ligação semelhantes, dada a semelhança das suas propriedades mecânicas. Um terceiro adesivo, de propriedades mecânicas bastante inferiores originou resultados menos promissores. A ligação tende a ser tanto mais resistente quanto maior for o seu comprimento. Em termos da influência da secção transversal do laminado, é notória a maior capacidade resistente da ligação para laminados com área de secção transversal superior. A utilização da metodologia DIC permitiu concluir que os mecanismos resistentes da ligação são fortemente dependentes das propriedades resistentes do adesivo.FCT e cofinanciado pelo Fundo Europeu de Desenvolvimento Regional (FEDER) através do Program
a Operacional Fatores de Competitividade e internacionalização (POCI) e do Programa Regional d
e Lisboa no âmbito dos projetos FRPLongDur POCI-01-0145-FEDER-016900 (PTDC/ECM-EST/1282/2014) e POCI-01-0145-FEDER-007633. S&P Clever
Reinforcement (oferta do laminado de CFK e adesivo S&P Resin 220) e Sika (oferta do adesivo SikaDur 30
Leukocyte ratios are useful early predictors for adverse outcomes of COVID-19 infection
Leukocyte biomarkers, including the neutrophil-to-lymphocyte (NLR), monocyte-to-lymphocyte-(MLR), platelet-to-lymphocyte (PLR) ratios and systemic immune-inflammation index (SII) have been associated with severity and mortality of patients with COVID-19. The purpose of this study was to evaluate the association of baseline leukocyte biomarkers calculated in the emergency department (ED) with the disease severity and mortality. This was a retrospective cohort study that evaluated 1,535 (mean age 57+18 years) patients with SARS-CoV-2 infection in the ED of a single reference center. Outcomes were severity, defined as intensive care unit (ICU) admission requirement, and in-hospital mortality. All leukocyte biomarkers were calculated in the ED before the hospital admission. Their ability to predict the severity and mortality was measured using receiver operating characteristic (ROC) curves. Severity and mortality were observed in 30.9% and 12.6% of the patients, respectively, and were significantly correlated with NLR, MLR, PLR and SII, but only NLR was independently associated with both outcomes on multivariate analysis. Analysis of ROC curves revealed that NLR (0.78 for severity and 0.80 for mortality) and SII (0.77 for severity and 0.75 for mortality) had the best ability to predict mortality, when compared to other ratios. The highest AUC was observed for NLR, employing cut-off points of 5.4 for severity and 5.5 for mortality. Leukocyte biomarkers, particularly NLR, are capable of predicting the severity and mortality of patients with SARS-CoV-2 infection and could be important adjunct tools to identify patients in the ED that are more prone to develop adverse outcomes
TCTEX1D4, a novel protein phosphatase 1 interactor: connecting the phosphatase to the microtubule network
Reversible phosphorylation plays an important role as a mechanism of intracellular control in eukaryotes. PPP1, a major eukaryotic Ser/Thr-protein phosphatase, acquires its specificity by interacting with different protein regulators, also known as PPP1 interacting proteins (PIPs). In the present work we characterized a physiologically relevant PIP in testis. Using a yeast two-hybrid screen with a human testis cDNA library, we identified a novel PIP of PPP1CC2 isoform, the T-complex testis expressed protein 1 domain containing 4 (TCTEX1D4) that has recently been described as a Tctex1 dynein light chain family member. The overlay assays confirm that TCTEX1D4 interacts with the different spliced isoforms of PPP1CC. Also, the binding domain occurs in the N-terminus, where a consensus PPP1 binding motif (PPP1BM) RVSF is present. The distribution of TCTEX1D4 in testis suggests its involvement in distinct functions, such as TGFβ signaling at the blood-testis barrier and acrosome cap formation. Immunofluorescence in human ejaculated sperm shows that TCTEX1D4 is present in the flagellum and in the acrosome region of the head. Moreover, TCTEX1D4 and PPP1 co-localize in the microtubule organizing center (MTOC) and microtubules in cell cultures. Importantly, the TCTEX1D4 PPP1BM seems to be relevant for complex formation, for PPP1 retention in the MTOC and movement along microtubules. These novel results open new avenues to possible roles of this dynein, together with PPP1. In essence TCTEX1D4/PPP1C complex appears to be involved in microtubule dynamics, sperm motility, acrosome reaction and in the regulation of the blood-testis barrier
An intriguing shift occurs in the novel protein phosphatase 1 binding partner, TCTEX1D4: evidence of positive selection in a pika model
T-complex testis expressed protein 1 domain containing 4 (TCTEX1D4) contains the canonical phosphoprotein phosphatase 1 (PPP1) binding motif, composed by the amino acid sequence RVSF. We identified and validated the binding of TCTEX1D4 to PPP1 and demonstrated that indeed this protein is a novel PPP1 interacting protein. Analyses of twenty-one mammalian species available in public databases and seven Lagomorpha sequences obtained in this work showed that the PPP1 binding motif 90RVSF93 is present in all of them and is flanked by a palindromic sequence, PLGS, except in three species of pikas (Ochotona princeps, O. dauurica and O. pusilla). Furthermore, for the Ochotona species an extra glycosylation site, motif 96NLS98, and the loss of the palindromic sequence were observed. Comparison with other lagomorphs suggests that this event happened before the Ochotona radiation. The dN/dS for the sequence region comprising the PPP1 binding motif and the flanking palindrome highly supports the hypothesis that for Ochotona species this region has been evolving under positive selection. In addition, mutational screening shows that the ability of pikas TCTEX1D4 to bind to PPP1 is maintained, although the PPP1 binding motif is disrupted, and the N- and C-terminal surrounding residues are also abrogated. These observations suggest pika as an ideal model to study novel PPP1 complexes regulatory mechanisms
Predominance of Leishmania (Leishmania) amazonensis DNA in Lutzomyia longipalpis sand flies (Diptera: Psychodidae) from an endemic area for leishmaniasis in Northeastern Brazil
Leishmaniasis is a serious public health concern in the Northeastern region of Brazil, where the sand fly fauna is well studied, although few species have been identified as competent vectors. The detection of Leishmania spp. parasites in wild-caught sand flies could help sanitary authorities draw strategies to avoid the transmission of the parasites and, therefore, the incidence of leishmaniases. We detected Leishmania DNA in wild-caught sand flies and correlated that data with aspects of sand fly ecology in the Caxias municipality, Maranhao State, Brazil. The sand flies were sampled in the peridomicile (open areas in the vicinity of human residences) and intradomicile (inside the residences) from July/2019 to March/2020. Leishmania DNA was detected in females, targeting a fragment of the Internal Transcribed Spacer (ITS1) from ribosomal DNA. Among the fourteen species of sand flies identified, five (Lutzomyia longipalpis, Nyssomyia whitmani, Evandromyia evandroi, Micropygomyia trinidadensis, and Micropygomyia quinquefer) harbored DNA of Leishmania (Leishmania) amazonensis. The most abundant species in rural (Ny. whitmani: 35.2% and Ev. evandroi: 32.4%) and urban areas (Lu. longipalpis: 89.8%) are the permissive vectors of L. (L.) amazonensis, especially Ny. whitmani, a known vector of causative agents of cutaneous leishmaniasis. Although Lu. longipalpis is the vector of L. (L.) infantum, which was not detected in this study, its permissiveness for the transmission of L. (L.) amazonensis has been reported. We suspect that visceral leishmaniasis and cutaneous leishmaniasis are caused by L. (L.) amazonensis, and the transmission may be occurring through Lu. longipalpis, at least in the urban area
Not so pseudo: the evolutionary history of protein phosphatase 1 regulatory subunit 2 and related pseudogenes
Background: Pseudogenes are traditionally considered “dead” genes, therefore lacking biological functions. This
view has however been challenged during the last decade. This is the case of the Protein phosphatase 1 regulatory
subunit 2 (PPP1R2) or inhibitor-2 gene family, for which several incomplete copies exist scattered throughout the
genome.
Results: In this study, the pseudogenization process of PPP1R2 was analyzed. Ten PPP1R2-related pseudogenes
(PPP1R2P1-P10), highly similar to PPP1R2, were retrieved from the human genome assembly present in the
databases. The phylogenetic analysis of mammalian PPP1R2 and related pseudogenes suggested that PPP1R2P7
and PPP1R2P9 retroposons appeared before the great mammalian radiation, while the remaining pseudogenes are
primate-specific and retroposed at different times during Primate evolution. Although considered inactive, four of
these pseudogenes seem to be transcribed and possibly possess biological functions. Given the role of PPP1R2 in
sperm motility, the presence of these proteins was assessed in human sperm, and two PPP1R2-related proteins
were detected, PPP1R2P3 and PPP1R2P9. Signatures of negative and positive selection were also detected in
PPP1R2P9, further suggesting a role as a functional protein.
Conclusions: The results show that contrary to initial observations PPP1R2-related pseudogenes are not simple
bystanders of the evolutionary process but may rather be at the origin of genes with novel functions.publishe
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