O comércio eletrónico e o turismo

Dissertação de Mestrado em Gestão de Empresas (MBA).As grandes alterações no setor do Turismo registadas nos últimos anos foram determinadas pela evolução das tecnologias da informação e comunicação, TICs. A aplicação B2B2C, suportada pelo e-commerce e pelo e-business, fizeram do Turismo um dos setores com maior crescimento na área das transações online. A Internet, através da sua interatividade e constante atualização de informação, conseguiu reduzir a intangibilidade do produto turístico, o que explica o sucesso desta ferramenta tanto para a indústria como para os consumidores. Entre as mais relevantes transformações destacam-se o surgimento de novos intermediários no mercado, bem como a possibilidade de venda direta e as mudanças de comportamento do consumidor. Com base na nova realidade da indústria turística e na alteração do comportamento dos consumidores, este estudo pretende analisar as novas tendências do mercado e contribuir para a compreensão dos fatores que influenciam a atitude do consumidor face ao eTourism. Os principais resultados obtidos indicam-nos que existem alguns determinantes com influência no planeamento das viagens através da Internet, tais como a experiência com eTourism, o e-commerce, a confiança e a avaliação do website.ABSTRACT: The main changes in the Tourism sector in recent years were determined by the evolution of information and communication technology, ICTs. The B2B2C application supported by e-commerce and the e-business, have made tourism one of the fastest growing sectors in the area of online transactions. The Internet, through its interactivity and constant information update, reduced the intangibility of the tourism product, which explains the success of this tool for both industry and consumers. Among the most significant changes we can point out the appearance of new market intermediaries as well as the possibility of direct sales and changes in consumer behaviour. Based on the new reality of tourism industry and the changes in consumer behaviour, this study aims to analyse the new market trends and to contribute to understand which factors influence consumer`s attitude towards eTourism. The main results show us that there are some determinants which influence travel planning through the Internet, such as experience with eTourism, trust, e-commerce and website evaluation

AVALIAÇÃO DAS PREVISÕES DO ATRASO ZENITAL TROPOSFÉRICO PARA A AMÉRICA DO SUL, OBTIDAS USANDO MODELO DE PREVISÃO NUMÉRICA DE TEMPO COM ALTA RESOLUÇÃO ESPACIAL

A Center for Weather Forecast and Climatic Studies of National Institute for Space Research (CPTEC/INPE) has provided to the Brazilian Geodetic community, since 2004, an alternative to correct the GNSS observables from the tropospheric refraction. Numerical Weather Prediction (NWP) Model is used to generate Zenital Tropospheric Delay (ZTD). For the version 1, it was developed a model with horizontal resolution of 100 km, which was updated with Eta model, with resolution of 20 km. This paper provides the most significative details of the current version, as well an evaluation of its quality, using for such ZTD estimates from GPS data collect at RBMC. Comparing to the old version, considerable improvement could be observed from the new model, mainly in Brasilia and Curitiba, reaching up to 55% improvement. When all stations were used in the quality control, almost null bias and RMS of about 4 to 5 cm could be observed.O Centro de Previsão de Tempo e Estudos Climáticos do Instituto Nacional de Pesquisas Espaciais (CPTEC/INPE) desde 2004 tem disponibilizado à comunidade geodésica uma alternativa para a modelagem dos efeitos dos gases atmosféricos na propagação dos sinais GNSS (Global Navigation Satellite Systems). Trata-se do emprego de modelos de Previsão Numérica de Tempo (PNT) para gerar previsões do Atraso Zenital troposférico (ZTD). Uma primeira versão foi desenvolvida utilizando um modelo de PNT com resolução horizontal de 100x100km, substituída posteriormente pela atual que passa a empregar o modelo regional Eta com resolução de 20x20km. O presente trabalho apresenta os detalhes mais significativos da atual versão, bem como uma avaliação utilizando estimativas do ZTD geradas a partir dos dados GPS da RBMC. Em uma comparação com a versão anterior, pode-se observar uma melhoria considerável na qualidade das previsões do ZTD em Brasília e Curitiba. Nessas regiões, onde a qualidade da versão anterior era comprometida, foram observadas melhorias na qualidade final de 50% e 55%, respectivamente. Nas demais estações da RBMC avaliadas observou-se que, independente das estações sazonais, o efeito sistemático é praticamente nulo e os valores do EMQ estão em torno de 4 a 5 cm

Verificação de antagonismo entre larvas de Schistosoma mansoni e larvas de outros Digenea em Biomphalaria tenagophila, molusco planobídeo de criadouro natural situado na região de Campinas, SP, Brasil

Foi observado o comportamento de larvas de S. mansoni em moluscos prévia e naturalmente infectados por larvas de outros Digenea. Foi verificado que as larvas de S. mansoni não se desenvolveram nos moluscos previamente infectados com purcocercárias longifurcadas com ocelos ou com furcocercárias longifurcadas sem ocelos. Observou-se resistência parcial ao desenvolvimento de S. mansoni nos moluscos previamente infectados por equinostomocercárias ou por distomocercárias com acúleo. A ausência de reação amebocitária em torno dos esporocistos de S. mansoni nos moluscos infectados por outros digenéticos parece indicar a não participação dos amebócitos na resistência oferecida ao desenvolvimento das larvas de S. mansoni.The objective of the present work is to study the development of S. mansoni larvae in snails found naturally infected by other digenetic trematode larvae. It was found that S. mansoni larvae did not develop in snails previoulsy infected by furcicercariae either with or without ocelli. Partial resistance to the development of S. mansoni was observed in snails previously infected by cercariae of Echinostomatidae or by cercariae with aculeus of Distomata. Absence of amoebocitary reaction around the S. mansoni sporocysts in snails previously infected by other digenetic trematodes indicates that amoebocytes did not play any role in the resistance mechanism

Impacto do rastreamento clínico e genético para neoplasia endócrina múltipla tipo 1

PURPOSE: To perform clinical and genetic screening for multiple endocrine neoplasia type 1 (MEN1) in patients at the Academic Hospital of the University of São Paulo School of Medicine, and to analyze its impact on clinical management of patients with MEN1. METHODS: The clinical diagnosis of MEN1 was made in accordance with the Consensus on multiple endocrine neoplasias. Mutation analysis of the entire MEN1 tumor suppressor gene and genetic screening of at-risk family members were performed by direct sequencing. To analyze the implementation of genetic diagnosis, the studied patients were separated into 3 groups: MEN1 index cases (group I), clinically diagnosed MEN1 cases (group II), and genetically diagnosed MEN1 cases (group III). RESULTS: In total, 154 individuals were clinically and genetically studied. We identified 12 different MEN1 mutations. Fifty-two MEN1 cases were identified: 13 in group I, 28 in group II, and 11 in group III. The mean age in group III (27.0 years) was significantly lower than in groups I (39.5 years) and II (42.4 years; P = 0.03 and P = 0.01, respectively). Patients in groups I and II mostly presented 2 or 3 MEN1-related tumors, while 81.8% of those in group III presented 1 or no MEN1-related tumor. Additionally, in group III, 45.4% of cases were asymptomatic, and no metastasis or death was verified. Surveillance for MEN1 mutations allowed the exclusion of 102 noncarriers, including a case of MEN1 phenocopy. CONCLUSION: Our data supports the benefits of clinical and genetic screening for multiple endocrine neoplasia type 1 in the management of this syndrome.OBJETIVOS: Realizar rastreamentos clínico e gênico para Neoplasia Endócrina Múltipla tipo 1 (NEM1) e analisar seu impacto no seguimento clínico desses pacientes no Hospital das Clínicas, SP. MÉTODOS: O diagnóstico clínico de NEM1 foi realizado de acordo com o Consenso sobre neoplasias endócrinas múltiplas. A análise genética para identificação de mutações foi realizada por sequenciamento automático de todas as regiões codificadoras e fronteiras exon/intron do gene MEN1. Os casos afetados foram sub-divididos em 3 grupos e analisados separadamente: casos-índices (grupo I), familiares diagnosticados clinicamente (grupo II) e genicamente (grupo III). RESULTADOS: Um total de 154 casos participou desse estudo, sendo 52 diagnosticados com NEM1: 13 do grupo I, 28 do grupo II e 11 do grupo III. A idade média ao diagnóstico no grupo III (27 anos) foi significativamente menor que a dos grupos I (39,5 anos; p = 0,03) e II (42,4 anos; p = 0,01). A maioria dos pacientes dos grupos I e II apresentou 2 ou 3 tumores, enquanto que 81,8% dos casos do grupo III apresentavam 1 ou nenhum tumor relacionado à NEM1. Além disto, 45,4% dos casos do grupo III eram assintomáticos, não sendo observados nenhuma metástase ou óbito. Os demais 102 familiares sob-risco estudados não herdaram mutação MEN1 e foram excluídos do rastreamento clínico. Um caso de fenocópia NEM1 foi também localizado. DISCUSSÃO: Nossos dados demonstraram importantes benefícios no seguimento dos pacientes NEM1, obtidos pela implementação dos rastreamentos clínico e gênico para essa doença

The impact of clinical and genetic screenings on the management of the multiple endocrine neoplasia type 1

PURPOSE: To perform clinical and genetic screening for multiple endocrine neoplasia type 1 (MEN1) in patients at the Academic Hospital of the University of São Paulo School of Medicine, and to analyze its impact on clinical management of patients with MEN1. METHODS: The clinical diagnosis of MEN1 was made in accordance with the Consensus on multiple endocrine neoplasias. Mutation analysis of the entire MEN1 tumor suppressor gene and genetic screening of at-risk family members were performed by direct sequencing. To analyze the implementation of genetic diagnosis, the studied patients were separated into 3 groups: MEN1 index cases (group I), clinically diagnosed MEN1 cases (group II), and genetically diagnosed MEN1 cases (group III). RESULTS: In total, 154 individuals were clinically and genetically studied. We identified 12 different MEN1 mutations. Fifty-two MEN1 cases were identified: 13 in group I, 28 in group II, and 11 in group III. The mean age in group III (27.0 years) was significantly lower than in groups I (39.5 years) and II (42.4 years; P = 0.03 and P = 0.01, respectively). Patients in groups I and II mostly presented 2 or 3 MEN1-related tumors, while 81.8% of those in group III presented 1 or no MEN1-related tumor. Additionally, in group III, 45.4% of cases were asymptomatic, and no metastasis or death was verified. Surveillance for MEN1 mutations allowed the exclusion of 102 noncarriers, including a case of MEN1 phenocopy. CONCLUSION: Our data supports the benefits of clinical and genetic screening for multiple endocrine neoplasia type 1 in the management of this syndrome.OBJETIVOS: Realizar rastreamentos clínico e gênico para Neoplasia Endócrina Múltipla tipo 1 (NEM1) e analisar seu impacto no seguimento clínico desses pacientes no Hospital das Clínicas, SP. MÉTODOS: O diagnóstico clínico de NEM1 foi realizado de acordo com o Consenso sobre neoplasias endócrinas múltiplas. A análise genética para identificação de mutações foi realizada por sequenciamento automático de todas as regiões codificadoras e fronteiras exon/intron do gene MEN1. Os casos afetados foram sub-divididos em 3 grupos e analisados separadamente: casos-índices (grupo I), familiares diagnosticados clinicamente (grupo II) e genicamente (grupo III). RESULTADOS: Um total de 154 casos participou desse estudo, sendo 52 diagnosticados com NEM1: 13 do grupo I, 28 do grupo II e 11 do grupo III. A idade média ao diagnóstico no grupo III (27 anos) foi significativamente menor que a dos grupos I (39,5 anos; p = 0,03) e II (42,4 anos; p = 0,01). A maioria dos pacientes dos grupos I e II apresentou 2 ou 3 tumores, enquanto que 81,8% dos casos do grupo III apresentavam 1 ou nenhum tumor relacionado à NEM1. Além disto, 45,4% dos casos do grupo III eram assintomáticos, não sendo observados nenhuma metástase ou óbito. Os demais 102 familiares sob-risco estudados não herdaram mutação MEN1 e foram excluídos do rastreamento clínico. Um caso de fenocópia NEM1 foi também localizado. DISCUSSÃO: Nossos dados demonstraram importantes benefícios no seguimento dos pacientes NEM1, obtidos pela implementação dos rastreamentos clínico e gênico para essa doença

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

Aim: Amazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types. Location: Amazonia. Taxon: Angiosperms (Magnoliids; Monocots; Eudicots). Methods: Data for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran\u27s eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny. Results: In the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R$^{2}$ = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R$^{2}$ = 28%). A greater number of lineages were significant indicators of geographic regions than forest types. Main Conclusion: Numerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions

Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates

Aim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis). Time period: Tree-inventory plots established between 1934 and 2019. Major taxa studied: Trees with a diameter at breast height (DBH) ≥ 9.55 cm. Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield. Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes. Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests. Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types

Geography and ecology shape the phylogenetic composition of Amazonian tree communities

AimAmazonia hosts more tree species from numerous evolutionary lineages, both young and ancient, than any other biogeographic region. Previous studies have shown that tree lineages colonized multiple edaphic environments and dispersed widely across Amazonia, leading to a hypothesis, which we test, that lineages should not be strongly associated with either geographic regions or edaphic forest types.LocationAmazonia.TaxonAngiosperms (Magnoliids; Monocots; Eudicots).MethodsData for the abundance of 5082 tree species in 1989 plots were combined with a mega-phylogeny. We applied evolutionary ordination to assess how phylogenetic composition varies across Amazonia. We used variation partitioning and Moran's eigenvector maps (MEM) to test and quantify the separate and joint contributions of spatial and environmental variables to explain the phylogenetic composition of plots. We tested the indicator value of lineages for geographic regions and edaphic forest types and mapped associations onto the phylogeny.ResultsIn the terra firme and várzea forest types, the phylogenetic composition varies by geographic region, but the igapó and white-sand forest types retain a unique evolutionary signature regardless of region. Overall, we find that soil chemistry, climate and topography explain 24% of the variation in phylogenetic composition, with 79% of that variation being spatially structured (R2 = 19% overall for combined spatial/environmental effects). The phylogenetic composition also shows substantial spatial patterns not related to the environmental variables we quantified (R2 = 28%). A greater number of lineages were significant indicators of geographic regions than forest types.Main ConclusionNumerous tree lineages, including some ancient ones (>66 Ma), show strong associations with geographic regions and edaphic forest types of Amazonia. This shows that specialization in specific edaphic environments has played a long-standing role in the evolutionary assembly of Amazonian forests. Furthermore, many lineages, even those that have dispersed across Amazonia, dominate within a specific region, likely because of phylogenetically conserved niches for environmental conditions that are prevalent within regions