825 resultados para Propensity
Repeated, long-distance migrations by a philopatric predator targeting highly contrasting ecosystems
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Long-distance movements of animals are an important driver of population spatial dynamics and determine the extent of overlap with area-focused human activities, such as fishing. Despite global concerns of declining shark populations, a major limitation in assessments of population trends or spatial management options is the lack of information on their long-term migratory behaviour. For a large marine predator, the tiger shark Galeocerdo cuvier, we show from individuals satellite-tracked for multiple years (up to 1101 days) that adult males undertake annually repeated, round-trip migrations of over 7,500 km in the northwest Atlantic. Notably, these migrations occurred between the highly disparate ecosystems of Caribbean coral reef regions in winter and high latitude oceanic areas in summer, with strong, repeated philopatry to specific overwintering insular habitat. Partial migration also occurred, with smaller, immature individuals displaying reduced migration propensity. Foraging may be a putative motivation for these oceanic migrations, with summer behaviour showing higher path tortuosity at the oceanic range extremes. The predictable migratory patterns and use of highly divergent ecosystems shown by male tiger sharks appear broadly similar to migrations seen in birds, reptiles and mammals, and highlight opportunities for dynamic spatial management and conservation measures of highly mobile sharks.
Repeated, long-distance migrations by a philopatric predator targeting highly contrasting ecosystems
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Long-distance movements of animals are an important driver of population spatial dynamics and determine the extent of overlap with area-focused human activities, such as fishing. Despite global concerns of declining shark populations, a major limitation in assessments of population trends or spatial management options is the lack of information on their long-term migratory behaviour. For a large marine predator, the tiger shark Galeocerdo cuvier, we show from individuals satellite-tracked for multiple years (up to 1101 days) that adult males undertake annually repeated, round-trip migrations of over 7,500 km in the northwest Atlantic. Notably, these migrations occurred between the highly disparate ecosystems of Caribbean coral reef regions in winter and high latitude oceanic areas in summer, with strong, repeated philopatry to specific overwintering insular habitat. Partial migration also occurred, with smaller, immature individuals displaying reduced migration propensity. Foraging may be a putative motivation for these oceanic migrations, with summer behaviour showing higher path tortuosity at the oceanic range extremes. The predictable migratory patterns and use of highly divergent ecosystems shown by male tiger sharks appear broadly similar to migrations seen in birds, reptiles and mammals, and highlight opportunities for dynamic spatial management and conservation measures of highly mobile sharks.
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INTRODUCTION: Development of a therapy for bone metastases is of paramount importance for castration-resistant prostate cancer (CRPC). The osteomimetic properties of CRPC confer a propensity to metastasize to osseous sites. Micro-ribonucleic acid (miRNA) is non-coding RNA that acts as a post-transcriptional regulator of multiple proteins and associated pathways. Therefore identification of miRNAs could reveal a valid third generation therapy for CRPC. Areas covered: miR34a has been found to play an integral role in the progression of prostate cancer, particularly in the regulation of metastatic genes involved in migration, intravasation, extravasation, bone attachment and bone homeostasis. The correlation between miR34a down-regulation and metastatic progression has generated substantial interest in this field. Expert opinion: Examination of the evidence reveals that miR34a is an ideal target for gene therapy for metastatic CRPC. We also conclude that future studies should focus on the effects of miR34a upregulation in CRPC with respect to migration, translocation to bone micro-environment and osteomimetic phenotype development. The success of miR34a as a therapeutic is reliant on the development of appropriate delivery systems and targeting to the bone micro-environment. In tandem with any therapeutic studies, biomarker serum levels should also be ascertained as an indicator of successful miR34a delivery.
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Background: Non-invasive ventilation (NIV) is increasingly used in patients with Acute Respiratory Distress Syndrome (ARDS). Whether, during NIV, the categorization of ARDS severity based on the PaO2/FiO2 Berlin criteria is useful is unknown. The evidence supporting NIV use in patients with ARDS remains relatively sparse.
Methods: The Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study described the management of patients with ARDS. This sub-study examines the current practice of NIV use in ARDS, the utility of the PaO2/FiO2 ratio in classifying patients receiving NIV and the impact of NIV on outcome.
Results: Of 2,813 patients with ARDS, 436 (15.5%) were managed with NIV on days 1 and 2 following fulfillment of diagnostic criteria. Classification of ARDS severity based on PaO2/FiO2 ratio was associated with an increase in intensity of ventilatory support, NIV failure, and Intensive Care Unit (ICU) mortality. NIV failure occurred in 22.2% of mild, 42.3% of moderate and 47.1% of patients with severe ARDS. Hospital mortality in patients with NIV success and failure was 16.1 % and 45.4%, respectively. NIV use was independently associated with increased ICU (HR 1.446; [1.159-1.805]), but not hospital mortality. In a propensity matched analysis, ICU mortality was higher in NIV than invasively ventilated patients with a PaO2/FiO2 lower than 150 mmHg.
Conclusions: NIV was used in 15% of patients with ARDS, irrespective of severity category. NIV appears to be associated with higher ICU mortality in patients with a PaO2/FiO2 lower than 150 mmHg.
Trial Registration: ClinicalTrials.gov NCT02010073
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In the current study, we compared technical efficiency of smallholder rice farmers with and without credit in northern Ghana using data from a farm household survey. We fitted a stochastic frontier production function to input and output data to measure technical efficiency. We addressed self-selection into credit participation using propensity score matching and found that the mean efficiency did not differ between credit users and non-users. Credit-participating households had an efficiency of 63.0 percent compared to 61.7 percent for non-participants. The results indicate significant inefficiencies in production and thus a high scope for improving farmers’ technical efficiency through better use of available resources at the current level of technology. Apart from labour and capital, all the conventional farm inputs had a significant effect on rice production. The determinants of efficiency included the respondent’s age, sex, educational status, distance to the nearest market, herd ownership, access to irrigation and specialisation in rice production. From a policy perspective, we recommend that the credit should be channelled to farmers who demonstrate the need for it and show the commitment to improve their production through external financing. Such a screening mechanism will ensure that the credit goes to the right farmers who need it to improve their technical efficiency.
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This PhD by publication examines selected practice-based audio-visual works made by the author over a ten-year period, placing them in a critical context. Central to the publications, and the focus of the thesis, is an exploration of the role of sound in the creation of dialectic tension between the audio, the visual and the audience. By first analysing a number of texts (films/videos and key writings) the thesis locates the principal issues and debates around the use of audio in artists’ moving image practice. From this it is argued that asynchronism, first advocated in 1929 by Pudovkin as a response to the advent of synchronised sound, can be used to articulate audio-visual relationships. Central to asynchronism’s application in this paper is a recognition of the propensity for sound and image to adhere, and in visual music for there to be a literal equation of audio with the visual, often married with a quest for the synaesthetic. These elements can either be used in an illusionist fashion, or employed as part of an anti-illusionist strategy for realising dialectic. Using this as a theoretical basis, the paper examines how the publications implement asynchronism, including digital mapping to facilitate innovative reciprocal sound and image combinations, and the asynchronous use of ‘found sound’ from a range of online sources to reframe the moving image. The synthesis of publications and practice demonstrates that asynchronism can both underpin the creation of dialectic, and be an integral component in an audio-visual anti-illusionist methodology.
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As experiências precoces de vergonha, na infância e adolescência, cujas memórias assumem características traumáticas, e de centralidade para a identidade, estão associadas a maior propensão para a vergonha e psicopatologia na adultez. O presente estudo visou clarificar o impacto das características traumáticas e da centralidade, das memórias de vergonha, e das memórias precoces de calor e segurança, na qualidade de vinculação aos pais e ao par amoroso, apreciando a orientação sexual. Nesse sentido, 123 sujeitos, homossexuais masculinos (N = 53) e heterossexuais masculinos e femininos (N = 70), completaram a bateria de questionários de autorresposta, para avaliar as caraterísticas traumáticas e a centralidade das memórias de vergonha, as memórias precoces de calor e segurança, a qualidade de vinculação ao pai, à mãe e ao par amoroso, recolhidos a partir de amostra de conveniência não aleatória da população geral. Os resultados mostram que os homossexuais, comparativamente com os heterossexuais, apresentam níveis mais elevados de caraterísticas traumáticas e de centralidade para a identidade, das memórias de vergonha, a par de níveis inferiores de memórias precoces positivas. As caraterísticas traumáticas e de centralidade, das memórias de vergonha, surgem associadas, com intensidade tendencialmente superior nos homossexuais, à restrição da aquisição de autonomia, conferida pelo pai, à sua desvalorização e à ansiedade de separação materna. O vínculo inseguro, aos progenitores, perpetua-se à adultez e ao par amoroso. Relativamente aos heterossexuais, apurámos que o laço emocional e a ansiedade de separação e dependência, paterna e materna, surgem associados a maior confiança e menor evitamento, respetivamente, ao par amoroso. Paralelamente, a ansiedade de separação e dependência materna surge, ainda, associada a maior dependência daquela figura. Este estudo conclui que as experiências precoces de vergonha, na infância e adolescência, podem funcionar como memórias com caraterísticas traumáticas e autobiográficas, constituir marcos de referência centrais no que concerne à identidade e história de vida, sobretudo em homossexuais, com atribuição de significado a outras experiências de vida, nomeadamente no que respeita à vinculação ao par romântico. / Early experiences of shame, in childhood and adolescence, whose memories assume traumatic characteristics, and centrality to identity, are associated with greater propensity to shame and psychopathology in adulthood. The present study aimed to clarify the impact of traumatic features and centrality to identity of shame memories, and of early memories of warmth and safety, on quality of attachment to parents and the loving couple`s bond, considering sexual orientation. Accordingly, 123 subjects, male homosexuals (N = 53) and male and female (N = 70) heterosexuals, completed the battery of self-report questionnaires, to assess trauma characteristics and centrality of shame memories, early memories of warmth and safeness, quality of attachment to the father, mother and loving couple, collected from a non-random convenience sample from general population. The results point that homosexual men, compared with heterosexuals, show higher levels of traumatic characteristics and centrality to identity of shame memories, along with lower levels of early positive memories. Traumatic characteristics and centrality of shame memories arise associated, tendentiously with higher intensity in homosexuals, to restriction of autonomy`s acquisition, conferred by the father, his devaluation and maternal separation anxiety. The unsecured bond, to parents, perpetuates into adulthood and loving couple. Regarding heterosexuals, we found that emotional bond and separation anxiety and dependency, paternal and maternal, arise associated with greater confidence, and less avoidance, respectively, to the loving couple. Further, separation anxiety and mother`s dependency also appears associated with greater dependency to that figure. This study concludes that early experiences of shame, in childhood and adolescence, might function as memories with traumatic and autobiographical characteristics, produce landmarks of central reference regarding identity and life`s history, particularly in homosexual, with attribution of meaning to other life experiences, particularly in the linking to the romantic couple.
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Objetivos: O presente estudo tem como objetivo analisar as características estruturais, funcionais e relacionais-contextuais das redes sociais pessoais de famílias unipessoais idosas. Metodologia: Utilizámos para recolha de dados um questionário para caracterizar sociodemograficamente a amostra, o Instrumento de Análise da Rede Social Pessoal (versão para idosos) (IARSP-Idosos) (Guadalupe, 2010; Guadalupe e Vicente 2012) e a escala de solidão UCLA (Neto, 1989). Participantes: A amostra é constituída por 567 indivíduos com média de idades de 75,53 anos, maioritariamente do sexo feminino (63,0%; n = 357). Predominam os sujeitos casados (53,7%; n = 304), com filhos (87,8%; n = 498) e em situação de coabitação (n = 450; 79,4%). Contudo, 20,6% (n = 117) vivem sós, constituindo as famílias unipessoais. Resultados: As redes sociais dos idosos têm em média 7,99 elementos, predominantemente familiares (M = 76,89%). Os participantes percecionam um nível elevado de apoio por parte das suas redes. São redes coesas, pouco dispersas e os contactos entre os elementos são frequentes. As mulheres, os indivíduos solteiros, viúvos ou divorciados e os idosos sem filhos têm uma maior probabilidade de viverem sós (p < 0,05) e estes apresentam uma maior probabilidade de necessitar de apoio social formal (p < 0,05). As famílias unipessoais, quando comparadas com os que não vivem sós, apresentam um maior número de campos relacionais e maior proporção de relações de amizade e de vizinhança (p < 0,05). Têm menor perceção de apoio material e instrumental, informativo, companhia social, acesso a novos vínculos e reciprocidade de apoio (p < 0,05). Além disso, referem menor frequência de contactos e uma maior dispersão geográfica (p < 0,05). Nas famílias unipessoais, observou-se a existência de correlações negativas significativas (p < 0,05) entre a percepção de solidão e o tamanho da rede, a proporção das relações familiares na rede, o apoio emocional e informativo e a reciprocidade de apoio. CONCLUSÃO: Os idosos com famílias unipessoais percecionam menor apoio por parte das suas redes, tendo uma maior propensão à solidão. É fundamental, ao longo do ciclo vital, promover a quantidade e qualidade dos vínculos, no sentido de manter a efetividade do suporte das redes mesmo quando se vive só. / Objectives: The present study aims to analyze the structural, functional and relational-contextual characteristics of older single-person households. Methodology: We used as instruments a questionnaire to evaluate sociodemographic data, the Instrumento de Análise da Rede Social Pessoal (version for elderly people: IARSP-Idosos) (Guadalupe, 2010; Guadalupe e Vicente 2012) and the UCLA Loneliness Scale (Neto, 1989). Participants: The sample consists of 567 individuals with an average age of 75.53 years, mostly females (63.0%; n = 357). There is a predominance of married individuals (53.7%; n = 304) with children (87.8%; n = 498). Older people live mainly in cohabitation (n = 450; 79.4%), however 20.6% oh them live alone, constituting one-person households. Results: The elderly personal social networks have 8 elements, on average, with a predominance of family relationships (M = 76.89%). The participants perceived a high level of support from their networks. In general the networks are cohesive, with low dispersion and have frequent contacts. The women, single, widowed or divorced and childless elderly are more likely to live alone (p < 0.05) and to need social services support (p < 0.05). The single-person households, compared with those who do not live alone, have a greater number of relational fields and a higher proportion of friendships and neighborhood relations (p < 0.05). They have a lower perception of material and informative support, social company and acess to new ties and reciprocal support (p < 0.05). They also refer lowest frequency of contacts and a wider geographical dispersion (p < 0.05). In single-person households there was a negative significant correlation between the perception of loneliness and the social network size, the proportion of family relationships in the network, emotional and informational support and reciprocal support. Conclusions: The elderly single-person households perceived less support from their networks and a greater propensity to loneliness. It is critical to promot the quality of ties, rather then their quantity, throughout the life cycle, in order to maintain the network effectiveness even when the person lives alone.
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When a company desires to invest in a project, it must obtain resources needed to make the investment. The alternatives are using firm s internal resources or obtain external resources through contracts of debt and issuance of shares. Decisions involving the composition of internal resources, debt and shares in the total resources used to finance the activities of a company related to the choice of its capital structure. Although there are studies in the area of finance on the debt determinants of firms, the issue of capital structure is still controversial. This work sought to identify the predominant factors that determine the capital structure of Brazilian share capital, non-financial firms. This work was used a quantitative approach, with application of the statistical technique of multiple linear regression on data in panel. Estimates were made by the method of ordinary least squares with model of fixed effects. About 116 companies were selected to participate in this research. The period considered is from 2003 to 2007. The variables and hypotheses tested in this study were built based on theories of capital structure and in empirical researches. Results indicate that the variables, such as risk, size, and composition of assets and firms growth influence their indebtedness. The profitability variable was not relevant to the composition of indebtedness of the companies analyzed. However, analyzing only the long-term debt, comes to the conclusion that the relevant variables are the size of firms and, especially, the composition of its assets (tangibility).This sense, the smaller the size of the undertaking or the greater the representation of fixed assets in total assets, the greater its propensity to long-term debt. Furthermore, this research could not identify a predominant theory to explain the capital structure of Brazilian
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An important aspect of sustainability is to maintain biodiversity and ecosystem functioning while improving human well-being. For this, the ecosystem service (ES) approach has the potential to bridge the still existing gap between ecological management and social development, especially by focusing on trade-offs and synergies between ES and between their beneficiaries. Several frameworks have been proposed to account for trade-offs and synergies between ES, and between ES and other components of social-ecological systems. However, to date, insufficient explicit attention has been paid to the three facets encompassed in the ES concept, namely potential supply, demand, and use, leading to incomplete descriptions of ES interactions. We expand on previous frameworks by proposing a new influence network framework (INF) based on an explicit consideration of influence relationships between these three ES facets, biodiversity, and external driving variables. We tested its ability to provide a comprehensive view of complex social-ecological interactions around ES through a consultative process focused on environmental management in the French Alps. We synthetized the interactions mentioned during this consultative process and grouped variables according to their overall propensity to influence or be influenced by the system. The resulting directed sequence of influences distinguished between: (1) mostly influential variables (dynamic social variables and ecological state variables), (2) target variables (provisioning and cultural services), and (3) mostly impacted variables (regulating services and biodiversity parameters). We discussed possible reasons for the discrepancies between actual and perceived influences and proposed options to overcome them. We demonstrated that the INF holds the potential to deliver collective assessments of ES relations by: (1) including ecological as well as social aspects, (2) providing opportunities for colearning processes between stakeholder groups, and (3) supporting communication about complex social-ecological systems and consequences for environmental management.
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Thesis (Ph.D.)--University of Washington, 2016-08
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Thesis (Ph.D.)--University of Washington, 2016-07
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Thesis (Ph.D.)--University of Washington, 2016-08
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Purpose: The purpose of this paper is to analyse differences in the drivers of firm innovation performance across sectors. The literature often makes the assumption that firms in different sectors differ in their propensity to innovate but not in the drivers of innovation. The authors empirically assess whether this assumption is accurate through a series of econometric estimations and tests. Design/methodology/approach: The data used are derived from the Irish Community Innovation Survey 2004-2006. A series of multivariate probit models are estimated and the resulting coefficients are tested for parameter stability across sectors using likelihood ratio tests. Findings: The results indicate that there is a strong degree of heterogeneity in the drivers of innovation across sectors. The determinants of process, organisational, new to firm and new to market innovation varies across sectors suggesting that the pooling of sectors in an innovation production function may lead to biased inferences. Research limitations/implications: The implications of the results are that innovation policies targeted at stimulating innovation need to be tailored to particular industries. One size fits all policies would seem inappropriate given the large degree of heterogeneity observed across the drivers of innovation in different sectors. Originality/value: The value of this paper is that it provides an empirical test as to whether it is suitable to group sectoral data when estimating innovation production functions. Most papers simply include sectoral dummies, implying that only the propensity to innovate differs across sectors and that the slope of the coefficient estimates are in fact consistent across sectors.
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Adenosquamous carcinoma is a rare tumor with coexisting elements of infiltrating squamous cell carcinoma and adenocarcinoma. This tumor is reported to arise in different organs but rarely in the oesophagus. In most cases, it shows highly aggressive biological behaviour with high propensity to regional lymph-node metastasis and poor prognosis. We describe the management of a patient with an aggressive adenosquamous carcinoma of the esophagogastric junction.