51 research outputs found

    Tracking the spatial diffusion of influenza and norovirus using telehealth data: A spatiotemporal analysis of syndromic data

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    Background: Telehealth systems have a large potential for informing public health authorities in an early stage of outbreaks of communicable disease. Influenza and norovirus are common viruses that cause significant respiratory and gastrointestinal disease worldwide. Data about these viruses are not routinely mapped for surveillance purposes in the UK, so the spatial diffusion of national outbreaks and epidemics is not known as such incidents occur. We aim to describe the geographical origin and diffusion of rises in fever and vomiting calls to a national telehealth system, and consider the usefulness of these findings for influenza and norovirus surveillance. Methods: Data about fever calls (5- to 14-year-old age group) and vomiting calls (≥ 5-year-old age group) in school-age children, proxies for influenza and norovirus, respectively, were extracted from the NHS Direct national telehealth database for the period June 2005 to May 2006. The SaTScan space-time permutation model was used to retrospectively detect statistically significant clusters of calls on a week-by-week basis. These syndromic results were validated against existing laboratory and clinical surveillance data. Results: We identified two distinct periods of elevated fever calls. The first originated in the North-West of England during November 2005 and spread in a south-east direction, the second began in Central England during January 2006 and moved southwards. The timing, geographical location, and age structure of these rises in fever calls were similar to a national influenza B outbreak that occurred during winter 2005–2006. We also identified significantly elevated levels of vomiting calls in South-East England during winter 2005–2006. Conclusion: Spatiotemporal analyses of telehealth data, specifically fever calls, provided a timely and unique description of the evolution of a national influenza outbreak. In a similar way the tool may be useful for tracking norovirus, although the lack of consistent comparison data makes this more difficult to assess. In interpreting these results, care must be taken to consider other infectious and non-infectious causes of fever and vomiting. The scan statistic should be considered for spatial analyses of telehealth data elsewhere and will be used to initiate prospective geographical surveillance of influenza in England.

    Dynamic networks and behavior: separating selection from influence.

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    A current problem in the analysis of behavioral dynamics, given a simultaneously evolving social network, is the difficulty of separating effects of partner selection from effects of social influence. In this paper we present a recently developed family of statistical models that enables researchers to separate the two effects in a statistically adequate manner. To illustrate our method we make use of a three-wave panel measured in the years 1995-1997 at a school in the West of Scotland. We are able to assess the strength of selection and influence mechanisms associated with friendship networks of substance-using adolescents

    Optimal foraging and community structure: implications for a guild of generalist grassland herbivores

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    A particular linear programming model is constructed to predict the diets of each of 14 species of generalist herbivores at the National Bison Range, Montana. The herbivores have body masses ranging over seven orders of magnitude and belonging to two major taxa: insects and mammals. The linear programming model has three feeding constraints: digestive capacity, feeding time and energy requirements. A foraging strategy that maximizes daily energy intake agrees very well with the observed diets. Body size appears to be an underlying determinant of the foraging parameters leading to diet selection. Species that possess digestive capacity and feeding time constraints which approach each other in magnitude have the most generalized diets. The degree that the linear programming models change their diet predictions with a given percent change in parameter values (sensitivity) may reflect the observed ability of the species to vary their diets. In particular, the species which show the most diet variability are those whose diets tend to be balanced between monocots and dicots. The community-ecological parameters of herbivore body-size ranges and species number can possibly be related to foraging behavior.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47765/1/442_2004_Article_BF00377109.pd

    The relationship between green space and prosocial behaviour among children and adolescents: A systematic review

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    2020 Putra, Astell-Burt, Cliff, Vella, John and Feng. The plausible role of nearby green space in influencing prosocial behaviour among children and adolescents has been studied recently. However, no review has been conducted of the evidence testing the association between green space and prosocial behaviour. This systematic review addresses this gap among children and adolescents. Within this review, we propose a conceptual framework describing potential pathways linking green space to prosocial behaviour, discuss the direction, magnitude, moderators, and mediators of the association, and develop a narrative synthesis of future study directions. Out of 63 extracted associations from 15 studies, 44 were in the positive or expected direction, of which 18 were reported to be statistically significant (p \u3c 0.05). Overall, the current evidence shows that exposure to green space may potentially increase prosocial behaviour among children and adolescents, with some contingencies (e.g., child\u27s sex and ethnic background). However, the volume and quality of this evidence is not yet sufficient to draw conclusions on causality. Further, heterogeneity in the indicators of green space exposure could lead to mixed findings. In addition, none of the included studies investigated potential mediators. Nevertheless, this review provides preliminary evidence and a basis for further investigation with rigorous study methodology capable of drawing causal inferences and testing potential effect modifiers, linking pathways, and relevant green space measures

    Association between green space quality and prosocial behaviour: A 10-year multilevel longitudinal analysis of Australian children

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    2020 Elsevier Inc. Background: Current evidence from studies on green space and child prosocial behaviour suggests a paucity of studies investigating the plausible role of green space quality in shaping the development of prosocial behaviour. This study aimed to examine longitudinal association between green space quality and prosocial behaviour among children. Methods: We analysed 10-year longitudinal data (2004-2014) from the Longitudinal Study of Australian Children (LSAC), a nationally representative cohort study. Prosocial behaviour that covers positive behaviours (e.g. sharing, helping) was measured using a prosocial scale from Goodman\u27s Strengths and Difficulties Questionnaire (SDQ). Parents\u27 perceptions on the availability of good parks, playgrounds, and play space in the neighbourhood assessed green space quality. Multilevel linear regression models were used to examine potential changes in prosocial behaviour across childhood in relation to green space quality. A two-way interaction term between green space and age was fitted to assess potential differences in the effect of green space quality by age. Sensitivity analyses by child\u27s sex and history of residential movement were also performed. Results: From the analysis of 24,418 observations nested in 4969 children, prosocial behaviour was relatively high (mean = 8.13 out of 10; SD = 1.79) and about balanced proportions between girls (48.74%) and boys (51.26%) were included. Prosocial behaviour was higher among children whose parents agreed (β = 0.10; 95%CI = 0.04, 0.16) and strongly agreed (β = 0.20; 95%CI = 0.13, 0.27) to having quality green space in their neighbourhood. The benefit of exposure to favourable green space on prosocial behaviour was similar among both children who changed and did not change neighbourhood, but reported higher among boys than girls. Younger compared with older children or adolescents tended to benefit more by the presence of quality green space. Conclusion: Green space quality was positively associated with child prosocial behaviour. Boys and younger children tended to benefit more from quality green space. Future research might seek to identify preferred characteristics of quality green spaces, and to understand how these preferences vary by gender and age, to best support the development of prosocial behaviour across childhood and adolescence
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