1,909 research outputs found

    Topology and Dynamics in Complex Networks: The Role of Edge Reciprocity

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    A key issue in complex systems regards the relationship between topology and dynamics. In this work, we use a recently introduced network property known as steering coefficient as a means to approach this issue with respect to different directed complex network systems under varying dynamics. Theoretical and real-world networks are considered, and the influences of reciprocity and average degree on the steering coefficient are quantified. A number of interesting results are reported that can assist the design of complex systems exhibiting larger or smaller relationships between topology and dynamics

    Island spider origins show complex vertical stratification patterns in Macaronesia

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    1.Spiders are among the most diverse and yet threatened groups of arthropods in Macaronesia. Found in most habitat types, they occupy the vertical gradient of native forests from ground to canopy level. 2. We hypothesize that their vertical distribution is influenced by the colonization origin. As introduced species should arrive using shipping containers and similar means, they should mostly occupy the lower levels in the gradient, with potential negative effects on the indigenous epigean fauna. 3. Spiders were sampled from epigean to arboreal microhabitats (maximum height varying between 2 and 4 m) on 45 sites across five islands belonging to three archipelagos. The mean and range of vertical stratification were obtained for each captured species. These values were then compared between different colonization origins at Macaronesian and archipelagic levels. 4. Native non-endemic species were found at significantly higher vertical strata than both endemic and introduced species. Likewise, native non-endemics had a larger vertical range. These patterns were largely replicated across archipelagos, although there were exceptions. 5. Overall, introduced species do not seem to occur mostly at lower strata in the native forests of Macaronesia (at least in the studied vertical range) but seem to be vertically restricted in most settings with the exception of Madeira.info:eu-repo/semantics/publishedVersio

    Evolutionary Insights into IL17A in Lagomorphs

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    In leporids, IL17A had been implicated in the host defense against extracellular pathogens, such as Francisella tularensis that infects hares and rabbits and causes the zoonotic disease tularemia. Here, we studied IL17A from five lagomorphs, European rabbit, pygmy rabbit, brush rabbit, European brown hare, and American pika. We observed that this protein is highly conserved between these species, with a similarity of 97-99% in leporids and ~88% between leporids and American pika. The exon/intron structure, N-glycosylation sites, and cysteine residues are conserved between lagomorphs. However, at codon 88, one of the interaction sites between IL17A and its receptor IL17RA, there is an Arg>Pro mutation that only occurs in European rabbit and European brown hare. This could induce critical alterations in the IL17A structure and conformation and consequently modify its function. The differences observed between leporids and humans or rodents might also represent important alterations in protein structure and function. In addition, as for other interleukins, IL17A sequences of human and European rabbit are more closely related than the sequences of human and mouse or European rabbit and mouse. This study gives further support to the hypothesis that European rabbit might be a more suitable animal model for studies on human IL17.FCT and North Portugal Regional Operational Programme 2007/2013 (ON.2) grants supported this work

    Digital clinical guidelines modelling

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    Oliveira T., Costa A., Neves J., Novais P., Digital Clinical Guidelines Modelling, Modelling and Simulation 2011, Novais P., Machado J., Analide C., Abelha A., (Eds.) (ESM’2011 – The 2011 European Simulation and Modelling Conference, Guimarães, Portugal) EUROSIS Publisher, ISBN: 978-9077381-66-3, pp 392-398, 2011.Healthcare environments are very demanding, because practitioners are required to consult many patients in a short period of time, increasing the levels of stress which usually harms the outcome of healthcare processes. The short time practitioners have with their patients does not facilitate informed decision making and checking all possibilities. A possible solution is the use of guideline-based applications, because they have the potential of being an effective means of both changing the process of healthcare and improving its outcomes. However, current Clinical Guidelines are available in text format as long documents, which render them difficult to consult and to integrate in clinical Decision Support Systems. With this paper we present a new model for guideline interpretation, in order to facilitate de development of guideline-based Decision Support Systems and to increase the availability of Clinical Guidelines at the moment of the clinical process. This model will also provide mechanisms to comply with cases where incomplete and uncertain information is present. The development and implementation of this model will be presented in the following pages

    Performance as a classification criterion of tourist origins and destinations

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    The definition of performance variables, which can be used as indicators of the results obtained/to be obtained, is a fundamental prerequisite in the carrying out of any evaluation process. Portfolio analysis has been used as a tool for the study of market segments, namely of tourist destinations. However, a review of the literature did not identify a single case where the performance variable is adjusted to the nature of the object. In fact, contrary to many other situations, the use of performance variables in absolute terms does not appear to be the most recommendable solution given that the total volume is conditioned by the size of the territory and, above all, by the number of inhabitants. In other words, for a certain level of socio-economic development, larger countries (in terms of size and number of inhabitants) will tend to have higher absolute values. Besides this, the empirical studies reviewed contain little, or no, information about competition, being temporally static. Although in some cases growth rate is used as a variable, thus presupposing the consideration of two magnitudes in two different moments in time, more than one register per object is never considered, meaning that evolutive analyses are not viable. Consequently, a performance proxy was developed which enables a direct comparison between generating countries (origins) and between destinations, regardless of the number of inhabitants. The selection of the performance proxy can depend on the object of study. In any case, it should always permit the evaluation, in general terms, of the results obtained by the destination for the set of origins under analysis and the results generated by the origin for the set of destinations under study. The proposed tool is a component of a model for the identification of priority market segments, and is constituted by a system of orthogonal axes which produces four quadrants that are distinct in terms of intensity (axis OY) and growth (axis OX) of tourist flows. The tool, like the model, can be applied to any type of destination (city, region or country) and to any market segmentation criterion (geographic, demographic, behavioural, psychographic or other). In the study reported here, the instrument is applied to the 15 Member States of the European Union (before its expansion on May 1st 2004), for the period from 1996 to 2001. Eurostat was the sole source of data for the study. The UK and Ireland are the countries classified as ‘Progressing Origins’. With 16.8% of the population, they increased their contribution from 17.7% to 21.9% and are responsible for 38.7% of the growth that occurred between 1996 and 2001. Spain, Greece and Ireland are the countries classified as ‘Progressing Destinations’. With 14.4% of the population, they increased their share of the market from 21.5% to 24.2%, capturing 35.1% of the growth that occurred between 1996 and 2001

    Find it: an assistant home agent

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    Cognitive impaired population face with innumerable problems in their daily life. Surprisingly, they are not provided with any help to perform those tasks for which they have difficulties. As a consequence, it is necessary to develop systems that allow those people to live independently and autonomously. Living in a technological era, people could take advantage of the available technology, being provided with some solutions to their needs. This paper presents a platform that assists users with remembering where their possessions are. Mainly, an object recognition process together with an intelligent scheduling applications are integrated in an Ambient Assisted Living (AAL) environment.(undefined

    An application to enrich the study of auditory emotion recognition

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    The ability to recognize emotions in spoken words is central in human communication and social relationships. When studying one's ability to perceive emotions, the standard paradigm is to have listeners choose which one of several emotion words best characterizes linguistically neutral utterances made by actors attempting to portray various emotional states. Usually, generic experiment control software are used, which may present several limitations. In this paper we present a novel approach to the problem, based on a mobile application that can be easily configured by the researcher to set up the desired protocol. This approach not only facilitates and improves study design and data collection, but also provides a plethora of new variables about the participants that, to the best of our knowledge, have never been considered before in this domain, including behavioural research.This work has been supported by COMPETE: POCI-01-0145-FEDER-007043 and FCT - Fundacao para a Ciencia e Tecnologia under projects UID/CEC/00319/2013 and PTDC/MHN-PCN/3606/2012.info:eu-repo/semantics/publishedVersio
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