905 resultados para Hierarchical Bayes
Resumo:
The safety benefit of signalizing intersections of high-speed divided expressways is considered. Analyses were conducted on 50 and 55 mph and on 55 mph only intersections, comparing unsignalized and signalized intersections. Results of the 55 mph analysis are included in this report. Matched-pair analysis indicates that generally, signalized intersections have higher crash rate but lower costs per crash. On the other hand, before-and-after analysis (intersections signalized between 1994 and 2001) indicates lower crash rates (~30 percent) and total costs (~10 percent) after signalization. Empirical Bayes (EB) adjusted before-and-after analysis reduces estimates of safety benefit (crash rate) to about 20 percent. The study shows how commonly used analyses can differ in their results, and that there is great variability in the safety performance of individual signalized locations. This variability and the effect of EB adjustment are demonstrated through the use of innovative graphics.
Resumo:
Epidemiological processes leave a fingerprint in the pattern of genetic structure of virus populations. Here, we provide a new method to infer epidemiological parameters directly from viral sequence data. The method is based on phylogenetic analysis using a birth-death model (BDM) rather than the commonly used coalescent as the model for the epidemiological transmission of the pathogen. Using the BDM has the advantage that transmission and death rates are estimated independently and therefore enables for the first time the estimation of the basic reproductive number of the pathogen using only sequence data, without further assumptions like the average duration of infection. We apply the method to genetic data of the HIV-1 epidemic in Switzerland.
Resumo:
Mathematical methods combined with measurements of single-cell dynamics provide a means to reconstruct intracellular processes that are only partly or indirectly accessible experimentally. To obtain reliable reconstructions, the pooling of measurements from several cells of a clonal population is mandatory. However, cell-to-cell variability originating from diverse sources poses computational challenges for such process reconstruction. We introduce a scalable Bayesian inference framework that properly accounts for population heterogeneity. The method allows inference of inaccessible molecular states and kinetic parameters; computation of Bayes factors for model selection; and dissection of intrinsic, extrinsic and technical noise. We show how additional single-cell readouts such as morphological features can be included in the analysis. We use the method to reconstruct the expression dynamics of a gene under an inducible promoter in yeast from time-lapse microscopy data.
Resumo:
This article reviews the methodology of the studies on drug utilization with particular emphasis on primary care. Population based studies of drug inappropriateness can be done with microdata from Health Electronic Records and e-prescriptions. Multilevel models estimate the influence of factors affecting the appropriateness of drug prescription at different hierarchical levels: patient, doctor, health care organization and regulatory environment. Work by the GIUMAP suggest that patient characteristics are the most important factor in the appropriateness of prescriptions with significant effects at the general practicioner level.
Resumo:
SUMMARY The human auditory cortex, located on the supratemporal plane of the temporal lobe, is divided in a primary auditory area and several non-primary areas surrounding it. These different areas show anatomical and functional differences. Many studies have focussed on auditory areas in non-human primates, using investigation techniques such as electrophysiological recordings, tracing of neural connections, or immunohistochemical and histochemical staining. Some of these studies have suggested parallel and hierarchical organization of the cortical auditory areas as well as subcortical auditory relays. In humans, only few studies have investigated these regions immunohistochemically, but activation and lesion studies speak in favour of parallel and hierarchical organization, very similar to that of non-human primates. Calcium-binding proteins and metabolic markers were used to investigate possible correlates of hierarchical and parallel organization in man. Calcium-binding proteins, parvalbumin, calretinin and calbindin, modulate the concentration of intracellular free calcium ions and were found in distinct subpopulations of GABAergic neurons in non-human primates species. In our study, their distribution showed several differences between auditory areas: the primary auditory area was darkly stained for both parvalbumin and calbindin, and their expression rapidly decreased while moving away from the primary area. This staining pattern suggests a hierarchical organization of the areas, in which the more darkly stained areas could correspond to an earlier integration level and the areas showing light staining may correspond to higher level integration areas. Parallel organization of primary and non-primary auditory areas was suggested by the complementarity, within a given area, between parvalbumin and calbindin expression across layers. To investigate the possible differences in the energetic metabolism of the cortical auditory areas, several metabolic markers were used: cytochrome oxidase and LDH1 were used as oxidative metabolism markers and LDH5 was used as glycolytic metabolism marker. The results obtained show a difference in the expression of enzymes involved in oxidative metabolism between areas. In the primary auditory area the oxidative metabolism markers were maximally expressed in layer IV. In contrast, higher order areas showed maximal staining in supragranular layers. The expression of LDH5 varied in patches, but did not differ between the different hierarchical auditory areas. The distribution of the two LDH enzymes isoforms also provides information about cellular aspects of metabolic organization, since neurons expressed the LDH1 isoform whereas astrocytes express primarily LDH5, but some astrocytes also contained the LDH1 isoform. This cellular distribution pattern supports the hypothesis of the existence of an astrocyte-neuron lactate shuttle, previously suggested in rodent studies, and in particular of lactate transfer from astrocytes, which produce lactate from the glucose obtained from the circulation, to neurons that use lactate as energy substrate. In conclusion, the hypothesis of parallel and hierarchical organization of the auditory areas can be supported by CaBPs, cytochrome oxidase and LDH1 distribution. Moreover, the two LDHs cellular distribution pattern support the hypothesis of an astrocyte-neuron lactate shuttle in human cortex.
Resumo:
The websites are becoming the firms’ first contact interface with their clients. Hence, understanding customers’ online attitudes and behaviors have been capturing increased research attention. The extant research has pointed customers’ satisfaction with the websites as the main reason for customers’ online behaviors. This research has used mostly variables related to the characteristics of the websites as the predictors of customers’ website satisfaction. However, recent research shows that groups of individuals displaying distinctive characteristics react differently to the same context. Therefore, behavior may be considerably different among groups of customers. In this study, we develop a conceptual model of the influence of individual characteristics on the traditional website quality – website satisfaction relationship. We propose a model based on the construct of consumer technology attractiveness (CTA) to represent the genuine positive propensity of individuals toward technology. We further test the moderating effect of this construct on the commonly used predictors of customer’s website satisfaction using Hierarchical Multiple Regression. The empirical study was based on websites of banks operating in Portuguese market. The commercial banking industry is one of the Portuguese industries that better uses the Internet to establish relationships with clients. Data were collected through an online website satisfaction survey, participated by the lecturers and postgraduate students from four Portuguese Universities and Polytechnic Institutes. Our final sample comprised 276 valid questionnaires. Our study permits to conclude that the most commonly used antecedents of website overall satisfaction are still relevant for analyzing consumer’s satisfaction with the banks websites. We also conclude that CTA has a significant moderating effect on almost all customers’ website satisfaction variables used in the study. This study contributes to highlight the theoretical importance and significant influence of consumers’ personal characteristics on their online behavior. Moreover, for the practitioners, a better understanding of these individual characteristics will assist them in developing customized websites that will meet customers’ expectations. O estudo dos comportamentos dos consumidores em ambientes online tem vindo a ter um crescente interesse, uma vez que os websites estão a transformar-se num importante ponto de contacto entre as empresas e os seus clientes. A satisfação dos clientes com os websites tem sido apontada pela Literatura como o principal condicionante dos comportamentos online dos consumidores. No entanto, a investigação científica tem conseguido provar que grupos de indivíduos com características distintas reagem de forma diferente quando submetidos a contextos idênticos, o que poderá levar a diferenças significativas no comportamento online de consumidores pertencentes a diferentes grupos. Neste estudo desenvolvemos um modelo conceptual que reflecte a influência de características individuais na relação entre a qualidade e a satisfação com os websites. Propomos um modelo assente na atractividade tecnológica do consumidor (CTA), que representa a propensão genuína que os indivíduos possuem em relação à tecnologia. Testamos o efeito moderador deste conceito sobre as variáveis mais utilizadas nos estudos sobre a satisfação dos consumidores com os websites, utilizando a Regressão Múltipla Hierárquica. O estudo empírico baseou-se nos websites dos bancos que operam no mercado português, uma vez que este sector é um dos que melhor utiliza a Internet na sua relação com os clientes. Os dados foram recolhidos através de um questionário sobre satisfação com os websites, colocado online e dirigido a docentes e estudantes de programas de pós-graduações, mestrados e doutoramentos de quatro universidades e instituto politécnico portugueses, tendo resultado numa amostra final de 276 questionários validados estatisticamente. Este estudo permitiu concluir que as variáveis que são mais utilizadas como antecedentes da satisfação dos consumidores com os websites, continuam a ser igualmente válidas para a análise dos websites dos bancos. Também concluímos que a CTA tem efeitos moderadores significativos na grande maioria das variáveis utilizadas neste estudo. Assim, conseguimos realçar a importância teórica das características pessoais dos consumidores no seu comportamento online. Para os gestores, uma melhor compreensão destas características individuais permitir-lhes-á desenvolver websites customizados que irão satisfazer as expectativas dos seus clientes.
Resumo:
The objective of this research was to analyze the organizational culture of a Brazilian public hospital. It is a descriptive study with quantitative approach of data, developed in a public hospital of São Paulo State, Brazil. The sample was composed by 52 nurses and 146 nursing technicians and auxiliaries. Data were collected from January to June 2011 using the Brazilian Instrument for Assessing Organizational Culture – IBACO. The analysis of the organizational values showed the existence of hierarchical rigidity and centralization of power within the institution, as well as individualism and competition, which hinders teamwork. The values concerning workers’ well-being, satisfaction and motivation were not highly valued. In regard to organizational practices, the promotion of interpersonal relationship, continuous education, and rewarding practices were not valued either. It becomes apparent that traditional models of work organization support work practices and determine the organizational culture of the hospital.
Resumo:
Diante da crescente competitividade, característica do mercado global, e da necessidade de melhorar a eficiência e a produtividade nas organizações, torne-se imperativo o aperfeiçoamento, incessante, na forma de actuação dos gestores. Consciente que, até então, as empresas suportam, essencialmente, no sistema contabilístico, este que, muitas vezes, fornece informações insuficientes e restringidos à tomada de decisões de curto prazo, mostra-se necessário investir em sistemas de medição, ligado à estratégia organizacional, que permitam melhor planeamento e controlo e, ainda, gerar e medir indicadores de longo prazo. No intuito de contribuir para a melhoria do paradigma da gestão, mais concretamente da gestão das empresas Cabo-Verdianas, e, em particular a da empresa em estudo, propomos, como objectivo desta dissertação, o estudo da utilização das ferramentas de gestão tradicional, face às novas ferramentas emergentes. Nisto, apresentamos, como estudo de caso, a avaliação do sistema de controlo de gestão da Empresa Bento - Comércio, Construtores, Imobiliária e Investimentos, Sociedade Anónima, (Bento S.A.), analisando, à luz da literatura consultada, o sistema de gestão estratégica, seguido pela empresa de modo a poder propor eventuais melhorias. Durante a revisão bibliográfica, foram estudadas várias ferramentas da gestão estratégica, das quais escolhemos o Balanced Scorecard (BSC) como um instrumento capaz de responder às lacunas detectadas na estratégia de gestão da Empresa, em que após uma breve descrição dos aspectos teóricos do conceito, suportado nos estudos empíricos publicados, apresentámos uma proposta para sua adopção, concepção e implementação. É de realçar que, durante o estudo constatou-se, por parte da administração da empresa, uma maior consciência da importância da comunicação e divulgação da sua estratégia entre os diferentes níveis hierárquicos, o que evidencia que ela está, mesmo, disposta a apostar na sua inovação estratégica. With the raising competitiveness, characteristic of the global market, and of the need of improving the efficiency and productivity in organizations, the constant improvement in the way of acting of managers it becomes peremptory. Aware that, so far, enterprises support, essentially, on the accounting system, which, many times, gives restrict and insufficient information for the taking of decisions in a short term, it is shown to be necessary to invest in measuring systems, connected to the organizational strategy, which contains signs that allow a better planning and control and, furthermore, give birth to and measure signs on a long term. With the aim of contributing for the improvement of the managing pattern, specifically, the management of Cape Verdean enterprises, and, in particular, the one of the enterprise in study, we propose, as an aim of this dissertation, the study of the use of the traditional managing tools, in view of the emerging new tools. Thus, we present, as study case, the evaluation of the system of management control of the Enterprise Bento - Comércio, Construtores, Imobiliária e Investimentos, Sociedade Anónima, (Bento, S.A.), analyzing the system of strategic management, used by the enterprise to be able to propose eventual improvements. During the bibliographic revision, we studied many strategic management tools, among which we chose the Balanced Scorecard (BSC) as an instrument capable to respond to the gaps detected in the management strategy of the enterprise, in which, after a brief description of the theoretical aspects of the concept, supported on the empiric studies published, we present a proposal for its adoption, conception and implementation. We would like to accentuate that, during the study we noticed that there exists, on the behalf of the management of the enterprise, a major awareness of the importance of communication and diffusion of its strategy among the different hierarchical levels, what makes clear that the enterprise is really open to bet on its strategic innovation.
Resumo:
Objective To aprehend the social representations about the solvability in mental health care with users of the Family Health Strategy and professionals of family health teams and of the Center for Psychosocial Care. Method A qualitative study using semi-structured interviews for data collection, and the Alceste software for analysis. This software uses the Hierarchical Descending Classification based on the examination of lexical roots, considering the words as units and providing context in the corpus. Results The representations emerge in two opposing poles: the users require satisfaction with care and the professionals realize the need for improvement of health actions. Although the matricial support in mental health and the home visits are developed, the barriers related to investment in health, continuing education and organization of care persist. Conclusion The different representations enable improvements in customer service, solvability of care and aggregate knowledge and practices in the expanded perspective of health needs in the family, social and therapeutic context.
Resumo:
Peter Karlson and Martin Lüscher used the term pheromone for the first time in 1959 to describe chemicals used for intra-species communication. Pheromones are volatile or non-volatile short-lived molecules secreted and/or contained in biological fluids, such as urine, a liquid known to be a main source of pheromones. Pheromonal communication is implicated in a variety of key animal modalities such as kin interactions, hierarchical organisations and sexual interactions and are consequently directly correlated with the survival of a given species. In mice, the ability to detect pheromones is principally mediated by the vomeronasal organ (VNO), a paired structure located at the base of the nasal cavity, and enclosed in a cartilaginous capsule. Each VNO has a tubular shape with a lumen allowing the contact with the external chemical world. The sensory neuroepithelium is principally composed of vomeronasal bipolar sensory neurons (VSNs). Each VSN extends a single dendrite to the lumen ending in a large dendritic knob bearing up to 100 microvilli implicated in chemical detection. Numerous subpopulations of VSNs are present. They are differentiated by the chemoreceptor they express and thus possibly by the ligand(s) they recognize. Two main vomeronasal receptor families, V1Rs and V2Rs, are composed respectively by 240 and 120 members and are expressed in separate layers of the neuroepithelium. Olfactory receptors (ORs) and formyl peptide receptors (FPRs) are also expressed in VSNs. Whether or not these neuronal subpopulations use the same downstream signalling pathway for sensing pheromones is unknown. Despite a major role played by a calcium-permeable channel (TRPC2) present in the microvilli of mature neurons TRPC2 independent transduction channels have been suggested. Due to the high number of neuronal subpopulations and the peculiar morphology of the organ, pharmacological and physiological investigations of the signalling elements present in the VNO are complex. Here, we present an acute tissue slice preparation of the mouse VNO for performing calcium imaging investigations. This physiological approach allows observations, in the natural environment of a living tissue, of general or individual subpopulations of VSNs previously loaded with Fura-2AM, a calcium dye. This method is also convenient for studying any GFP-tagged pheromone receptor and is adaptable for the use of other fluorescent calcium probes. As an example, we use here a VG mouse line, in which the translation of the pheromone V1rb2 receptor is linked to the expression of GFP by a polycistronic strategy.
Resumo:
This study aimed to analyze the social representations in the professionals of technical staff, who work with children at USP daycare centers. Eight professionals of the nursing field underwent a semi-structured interview. The interviews were recorded and transcribed in their entirety and the content of the discourse was subjected to thematic-categorical analysis. The categories were transformed into variables and processed by the software Classification Hiérarchique Classificatoire et Cohésitive (CHIC®) and analyzed by the hierarchical similarity tree. The results indicate that actions to promote health are reported as educational and transformative, in which health care gains new meaning through contextualized conceptions in the field of child education. We conclude that professionals attribute new meanings to their practices in the health care environment of daycare centers as their representations shifts from the logic of the biomedical field to a logic of educational care. In this sense, they perceive themselves as being challenged to establish an interaction with the children in terms of their activities related to the promotion of health and in an educational act.
Resumo:
The aim of this study is to analyze and understand the reasons for the occurrence of sensitive hospitalizations in accordance with users. Qualitative study conducted with users who were admitted to Pedreira General Hospital, in São Paulo. The data was collected through semi structured interviews and thereafter, transcribed and processed in the electronic program Alceste. When analyzing the content, the access was seized fundamentally as an empirical category, bringing up problems that later deserved, from the Brazilian Ministry of Health, a specific Program to improve the quality and access to primary care. The hierarchical and pyramidal organization shape from the health system in the city of São Paulo can be one of the important aspects for the access matter and established as an important restricting factor in the primary care role in reducing or even preventing the occurrence of these hospitalizations.
Resumo:
Esta pesquisa gira à volta da avaliação do desempenho organizacional com enfoque no sistema denominado Balanced Scorecard. Esta ferramenta, criada no início da década de noventa, por David Norton e Robert Kaplan, tem vindo a contagiar os gestores, e nos dias de hoje várias são as organizações que beneficiam dela para obter excelência. A primeira metodologia foi apresentada em mil novecentos e noventa e três (1993), constituída por oito etapas. No ano de mil novecentos e noventa e seis (1996), os autores desenvolveram uma nova metodologia, melhorada, composta por dez etapas. Começámos por fazer um levantamento teórico dos conceitos ligados a esta ferramenta, as suas vantagens e desvantagens, as fases da sua execução, os possíveis obstáculos ao seu sucesso e os frutos que poderão ser colhidos com a sua implementação. Através de uma proposta de implementação, escolhemos o Comando da 1ª Região Militar, para verificar quais serão os impactos na gestão desta organização. Do diagnóstico situacional efectuado com base em entrevistas, análise documental e observação, verificámos que a organização possui algumas insuficiências ao nível do desempenho de gestão, derivadas sobretudo da situação logística e financeira. Na construção do mapa estratégico, principal componente do Balanced scorecard, vimo-nos na necessidade de deslocar a perspectiva do cliente ou de mercado para o topo de configuração, devido à natureza do objecto negocial da organização em estudo. O modelo de avaliação de desempenho desenvolvido evidenciou a importância que a utilização deste sistema poderá ter na melhoria das actividades castrenses, sobretudo pelo aumento do nível de comunicação entre os subgrupos e a gestão de topo, neste caso, o Pessoal de Comando e as Pequenas Unidades, devido à natureza e qualidade das informações fornecidas pelo mapa estratégico. The aim of this study is to look at the organizational performance measurement system, with a special emphasis upon the so called Balanced Scorecard System. This tool, created at the beginning of the 1990’s by David Norton and Robert Kaplan, has been gaining the enthusiasm of administrator, and at the present time, several organizations are using it in the search for excellence. The first methodology was presented in 1993 and was formed by eight steps. In 1996, however, its creators developed an improved version of this methodology, now composed by ten steps. We start by doing a research of the theoretical concepts related to this tool, its advantages and disadvantages, the stages of its implementation, possible obstacles to its success, and the benefits that can come from its use. Based on an implementation proposal, we chose the First Military Command Region of Cape Verde to study the possible impacts of this system on the management of that Institution. From an investigation on the existent situation, based on interviews, analysis of documents and “in locus” observation, we realised that the institution shows some administrative insufficiencies, mainly due to its logistics and financial situation. In the building of the strategic map, the main component of the Balanced Scorecard System, we were obliged to move the perspective of the client or the market to the top of the configuration, because of the nature of the trading object of the institution being studied. The performance measurement model developed, clearly showed the importance that the implementation of this system might have on the improvement of the Military activities, mainly because of the improvement on the type of communication that can be established between the subgroups and the higher hierarchical levels, in this case, the Commander Staff and the lower Units, due to the type and quality of the information provided by the strategic map.
Resumo:
BACKGROUND: Mitochondrial DNA sequencing increasingly results in the recognition of genetically divergent, but morphologically cryptic lineages. Species delimitation approaches that rely on multiple lines of evidence in areas of co-occurrence are particularly powerful to infer their specific status. We investigated the species boundaries of two cryptic lineages of the land snail genus Trochulus in a contact zone, using mitochondrial and nuclear DNA marker as well as shell morphometrics. RESULTS: Both mitochondrial lineages have a distinct geographical distribution with a small zone of co-occurrence. In the same area, we detected two nuclear genotype clusters, each being highly significantly associated to one mitochondrial lineage. This association however had exceptions: a small number of individuals in the contact zone showed intermediate genotypes (4%) or cytonuclear disequilibrium (12%). Both mitochondrial lineage and nuclear cluster were statistically significant predictors for the shell shape indicating morphological divergence. Nevertheless, the lineage morphospaces largely overlapped (low posterior classification success rate of 69% and 78%, respectively): the two lineages are truly cryptic. CONCLUSION: The integrative approach using multiple lines of evidence supported the hypothesis that the investigated Trochulus lineages are reproductively isolated species. In the small contact area, however, the lineages hybridise to a limited extent. This detection of a hybrid zone adds an instance to the rare reported cases of hybridisation in land snails.
Resumo:
Cape Verde is a tropical oceanic ecosystem, highly fragmented and dispersed, with islands physically isolated by distance and depth. To understand how isolation affects the ecological variability in this archipelago, we conducted a research project on the community structure of the 18 commercially most important demersal fishes. An index of ecological distance based on species relative dominance (Di) is developed from Catch Per Unit Effort, derived from an extensive database of artisanal fisheries. Two ecological measures of distance between islands are calculated: at the species level, DDi, and at the community level, DD (sum of DDi). A physical isolation factor (Idb) combining distance (d) and bathymetry (b) is proposed. Covariance analysis shows that isolation factor is positively correlated with both DDi and DD, suggesting that Idb can be considered as an ecological isolation factor. The effect of Idb varies with season and species. This effect is stronger in summer (May to November), than in winter (December to April), which appears to be more unstable. Species react differently to Idb, independently of season. A principal component analysis on the monthly (DDi) for the 12 islands and the 18 species, complemented by an agglomerative hierarchical clustering, shows a geographic pattern of island organization, according to Idb. Results indicate that the ecological structure of demersal fish communities of Cape Verde archipelago, both in time and space, can be explained by a geographic isolation factor. The analytical approach used here is promising and could be tested in other archipelago systems.