944 resultados para stop and search


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Both genetic factors and life experiences appear to be important in shaping dogs' responses in a test situation. One potentially highly relevant life experience may be the dog's training history, however few studies have investigated this aspect so far. This paper briefly reviews studies focusing on the effects of training on dogs' performance in cognitive tasks, and presents new, preliminary evidence on trained and untrained pet dogs' performance in an 'unsolvable task'. Thirty-nine adult dogs: 13 trained for search and rescue activities (S&R group), 13 for agility competition (Agility group) and 13 untrained pets (Pet group) were tested. Three 'solvable' trials in which dogs could obtain the food by manipulating a plastic container were followed by an 'unsolvable' trial in which obtaining the food became impossible. The dogs' behaviours towards the apparatus and the people present (owner and researcher) were analysed. Both in the first 'solvable' and in the 'unsolvable' trial the groups were comparable on actions towards the apparatus, however differences emerged in their human-directed gazing behaviour. In fact, results in the 'solvable' trial, showed fewer S&R dogs looking back at a person compared to agility dogs, and the latter alternating their gaze between person and apparatus more frequently than pet dogs. In the unsolvable trial no difference between groups emerged in the latency to look at the person however agility dogs looked longer at the owner than both pet and S&R dogs; whereas S&R dogs exhibited significantly more barking (always occurring concurrently to looking at the person or the apparatus) than both other groups. Furthermore, S&R dogs alternated their gaze between person and apparatus more than untrained pet dogs, with agility dogs falling in between these two groups. Thus overall, it seems that the dogs' human-directed communicative behaviours are significantly influenced by their individual training experiences. © 2009 Elsevier B.V. All rights reserved.

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A estirpe Bacillus licheniformis I89 possui a capacidade de produzir alguns compostos com actividade antibacteriana. No presente estudo, a separação desses compostos foi realizada através da aplicação de vários procedimentos, incluindo extracção em fase sólida e cromatografia liquida de alta pressão. Dois destes compostos bioactivos constituem o lantibiótico de classe II lichenicidina e são caracterizados pela massas molecular de 3250 Da (Bliα) e 3020 Da (Bliβ). O cluster responsável pela biossíntese da lichenicidina foi heterologamente expresso em Escherichia coli, constituindo a primeira descrição da produção de um lantibiótico totalmente in vivo num hospedeiro Gram-negativo. Este sistema foi subsequentemente explorado com o objectivo de relacionar cada proteína codificada no cluster genético da lichenicidina na produção dos péptidos Bliα e Bliβ. O desenvolvimento do sistema de trans complementação possibilitou a produção de variantes destes péptidos. A análise das massas moleculares destas variantes assim como a análise dos padrões de fragmentação obtidos por MS/MS permitiu a revisão de algumas das características estruturais previamente proposta para Bliα e Bliβ. A análise dos genes hipoteticamente envolvidos na protecção da estirpe produtora contra a acção antibiótica da lichenicidina revelou, que em E. coli, a sua ausência não resulta no aumento da susceptibilidade a este composto. Verificou-se também que a presença destes genes não é essencial para a produção de lichenicidina em E. coli. Foi também confirmado experimentalmente que a membrana externa da E. coli constitui uma barreira natural para a entrada dos péptidos na célula. De facto, uma das características intrigantes da produção de lichenicidina por uma bactéria de Gram negativo reside no mecanismo de transporte dos dois péptidos através da membrana externa. Neste estudo foi demonstrado que na ausência da proteína de membrana TolC, a massa molecular de Bliα e Bliβ não foi identificada no sobrenadante de E. coli, demonstrando assim que a sua presença no ambiente extra-celular não se devia a um processo de lise bacteriana. Foi ainda avaliada a capacidade da maquinaria biossintética da lichenicidina para produzir o lantibiótico haloduracina, através do processamento de chimeras lichenicidina-haloduracina, contudo, os resultados foram negativos. Verificou-se ainda que em determinadas condições de incubação, a diferenciação da morfologia original da estirpe B. licheniformis I89 pode ocorrer. Esta dissociação implicou a transição da colónia parental e rugosa para uma colónia de aparência mais simples e suave. Desta forma, as diferenças das duas morfologias em termos de taxa de crescimento, esporulação e actividade antibiótica foram investigadas. Considerando especificamente Bliα e Bliβ verificou-se que a abundância destes péptidos nas culturas do fenótipo fino é geralmente inferior aquela identificada nas culturas do fenótipo parental. Por último, a diversidade de elementos genéticos constituintes de péptido sintetases não ribossomais (NRPS) foi investigada em lagoas no centro de Portugal e em solos provenientes de caves do sul de Portugal, revelando a presença de potenciais novas NRPS nestes ambientes.

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The possibility of creating baryon asymmetry at the electroweak phase transition in the minimal supersymmetric standard model is considered for the case when right-handed squarks are much lighter than left-handed ones. It is shown that the usual requirement upsilon(T-c)/T-c greater than or similar to 1 for baryogenesis can be satisfied in a range of the parameters of the model, consistent with present experimental bounds.

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This research intends to examine if there were significant differences on the brand engagement and on the electronic word of mouth (e-WOM)1 referral intention through Facebook between Generation X and Generation Y (also called millennials). Also, this study intends to examine if there are differences in the motivations that drive these generations to interact with brands through Facebook. Results indicated that Generation Y members consumed more content on Facebook brands’ pages than Generation X. Also, they were more likely to have an e-WOM referral intention as well as being more driven by brand affiliation and opportunity seeking. Finally, currently employed individuals were found to contribute with more content than students. This study fills the gap in the literature by addressing how marketing professionals should market their brand and interact and engage with their customers, based on customers’ generational cohort.

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What are ways of searching in graphs? In this class, we will discuss basics of link analysis, including Google's PageRank algorithm as an example. Readings: The PageRank Citation Ranking: Bringing Order to the Web, L. Page and S. Brin and R. Motwani and T. Winograd (1998) Stanford Tecnical Report

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Ante el crecimiento económico y la transformación del país. Con el incremento de los flujos de comercio y el transporte, Bogotá, buscando reducir el impacto ambiental por la cantidad de vehículos y reducir la congestión, ha decidido implementar políticas públicas que restringen el ingreso de vehículos de carga pesada por la ciudad. Esto crea una necesidad de espacios a las afueras de la ciudad, cerca de las zonas logísticas y con la capacidad de ofrecer a los transportadores los servicios de alimentación, parqueadero, alojamiento y reabastecimiento de combustible. Atendiendo estas necesidades, Stop And Go surge como proyecto de inversión que pretende constituir un espacio eficazmente equipado, con altos estándares de calidad y de bajo costo. En el presente documento se desarrolla el plan de negocios y de viabilidad, recorriendo la estructura de la organización, las características de los servicios ofrecidos, la propuesta de mercadeo y la viabilidad estratégica y financiera.

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There are three key driving forces behind the development of Internet Content Management Systems (CMS) - a desire to manage the explosion of content, a desire to provide structure and meaning to content in order to make it accessible, and a desire to work collaboratively to manipulate content in some meaningful way. Yet the traditional CMS has been unable to meet the latter of these requirements, often failing to provide sufficient tools for collaboration in a distributed context. Peer-to-Peer (P2P) systems are networks in which every node is an equal participant (whether transmitting data, exchanging content, or invoking services) and there is an absence of any centralised administrative or coordinating authorities. P2P systems are inherently more scalable than equivalent client-server implementations as they tend to use resources at the edge of the network much more effectively. This paper details the rationale and design of a P2P middleware for collaborative content management.

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Brazil`s State of Sao Paulo Research Foundation

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This presentation was offered as part of the CUNY Library Assessment Conference, Reinventing Libraries: Reinventing Assessment, held at the City University of New York in June 2014.

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Efficiently inducing precise causal models accurately reflecting given data sets is the ultimate goal of causal discovery. The algorithm proposed by Wallace et al. [10] has demonstrated its ability in discovering Linear Causal Models from data. To explore the ways to improve efficiency, this research examines three different encoding schemes and four searching strategies. The experimental results reveal that (1) specifying parents encoding method is the best among three encoding methods we examined; (2) In the discovery of linear causal models, local Hill climbing works very well compared to other more sophisticated methods, like Markov Chain Monte Carto (MCMC), Genetic Algorithm (GA) and Parallel MCMC searching.

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This paper analyzes corruption as a collusive act which requires the participation of two willing partners. An agent intending to engage in a corrupt act must search for a like-minded partner. When many people in the economy are corrupt, such a search is more likely to be fruitful. Thus when an agent engages in a search, he raises the net benefit of searching for other similar agents in the economy, creating an externality. This introduces a non-convexity in the model, which consequently has multiple equilibria. The economy can be in stable equilibrium with a high or low level of corruption.

Starting from the high-corruption equilibrium, a sufficient increase in vigilance triggers a negative cascade, leading the economy to a new equilibrium in which no agent finds it profitable to search for corrupt partners. The no-corruption equilibrium continues to be stable if vigilance is then relaxed. This suggests that the correct way to deal with corruption is to launch a ``big push'' with large amounts of resources. Once the level of corruption declines, these resources can be withdrawn.

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This paper presents a discrete-time sequential stochastic asset-selling problem with an infinite planning horizon, where the process of selling the asset may reach a deadline at any point in time with a probability. It is assumed that a quitting offer is available at every point in time and search skipping is permitted. Thus, decisions must be made as to whether or not to accept the quitting offer, to accept an appearing buyer’s offer, and to conduct a search for a buyer. The main purpose of this paper is to clarify the properties of the optimal decision rules in relation to the model’s parameters.

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Em modelos de competição de preços, somente um custo de procura positivo por parte do consumidor não gera equilíbrio com dispersão de preços. Já modelos dinâmicos de switching cost consistentemente geram este fenômeno bastante documentado para preços no varejo. Embora ambas as literaturas sejam vastas, poucos modelos tentaram combinar as duas fricções em um só modelo. Este trabalho apresenta um modelo dinâmico de competição de preços em que consumidores idênticos enfrentam custos de procura e de switching. O equilíbrio gera dispersão nos preços. Ainda, como os consumidores são obrigados a se comprometer com uma amostra fixa de firmas antes dos preços serem definidos, somente dois preços serão considerados antes de cada compra. Este resultado independe do tamanho do custo de procura individual do consumidor.