186 research outputs found

    Pathogen persistence

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    Discuss the progression of their research into the ecology and evolution of horizontal and vertical transmission strategies in a model insect-virus interaction system

    Variation in life history and flight morphological traits in Speckled Wood (Pararge aegeria) butterflies infected with a baculovirus.

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    Sub-lethal impacts are known to affect the insect-host relationship and have an important role in describing host dynamics. The impact of sub-lethal infections of pathogens on life history traits of affected hosts has been understudied in natural or semi-natural systems. The Speckled Wood (Pararge aegeria) is a satyrine butterfly that is common in temperate zones and has been extensively used as a model system for evolutionary ecology studies. It is known that the deployment of the immune system within this species, as with other invertebrates, is energetically costly and may result in trade-offs with fitness-related traits. In this study, we investigated the sub-lethal effect of exposure to Autographa californica multiple nucleopolyhedrovirus (AcMNPV) on life history and flight morphological traits of P. aegeria. Larvae were inoculated with increasing doses of AcMNPV and measurements made of life history and flight morphology traits. Generally, larvae exposed to virus took longer to develop to pupae and larval mass acquisition per day was significantly reduced in viral exposed larvae. However, viral exposed larvae were able to attain the same pupal mass and their duration as pupae was the same as controls. Forewing length, forewing aspect ratio, dry thorax mass and forewing loading were related to sex and bioassay differences but there was no evidence of any viral impact on these measures. Adult male butterflies had significantly less basal wing melanisation when exposed to virus compared to control males but there was no difference between females. Implications for population dynamics of P. aegeria are discussed

    Co-occurrence and clustering of health conditions at age 11: cross-sectional findings from the Millennium Cohort Study

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    OBJECTIVES: To identify patterns of co-occurrence and clustering of 6 common adverse health conditions in 11-year-old children and explore differences by sociodemographic factors. DESIGN: Nationally representative prospective cohort study. SETTING: Children born in the UK between 2000 and 2002. PARTICIPANTS: 11 399 11-year-old singleton children for whom data on all 6 health conditions and sociodemographic information were available (complete cases). MAIN OUTCOME MEASURES: Prevalence, co-occurrence and clustering of 6 common health conditions: wheeze; eczema; long-standing illness (excluding wheeze and eczema); injury; socioemotional difficulties (measured using Strengths and Difficulties Questionnaire) and unfavourable weight (thin/overweight/obese vs normal). RESULTS: 42.4% of children had 2 or more adverse health conditions (co-occurrence). Co-occurrence was more common in boys and children from lower income households. Latent class analysis identified 6 classes: 'normative' (57.4%): 'atopic burdened' (14.0%); 'socioemotional burdened' (11.0%); 'unfavourable weight/injury' (7.7%); 'eczema/injury' (6.0%) and 'eczema/unfavourable weight' (3.9%). As with co-occurrence, class membership differed by sociodemographic factors: boys, children of mothers with lower educational attainment and children from lower income households were more likely to be in the 'socioemotional burdened' class. Children of mothers with higher educational attainment were more likely to be in the 'normative' and 'eczema/unfavourable weight' classes. CONCLUSIONS: Co-occurrence of adverse health conditions at age 11 is common and is associated with adverse socioeconomic circumstances. Holistic, child focused care, particularly in boys and those in lower income groups, may help to prevent and reduce co-occurrence in later childhood and adolescence

    Effect of classroom-based physical activity interventions on academic and physical activity outcomes: a systematic review and meta-analysis

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    BACKGROUND: Physical activity is associated with many physical and mental health benefits, however many children do not meet the national physical activity guidelines. While schools provide an ideal setting to promote children\u27s physical activity, adding physical activity to the school day can be difficult given time constraints often imposed by competing key learning areas. Classroom-based physical activity may provide an opportunity to increase school-based physical activity while concurrently improving academic-related outcomes. The primary aim of this systematic review and meta-analysis was to evaluate the impact of classroom-based physical activity interventions on academic-related outcomes. A secondary aim was to evaluate the impact of these lessons on physical activity levels over the study duration. METHODS: A systematic search of electronic databases (PubMed, ERIC, SPORTDiscus, PsycINFO) was performed in January 2016 and updated in January 2017. Studies that investigated the association between classroom-based physical activity interventions and academic-related outcomes in primary (elementary) school-aged children were included. Meta-analyses were conducted in Review Manager, with effect sizes calculated separately for each outcome assessed. RESULTS: Thirty-nine articles met the inclusion criteria for the review, and 16 provided sufficient data and appropriate design for inclusion in the meta-analyses. Studies investigated a range of academic-related outcomes including classroom behaviour (e.g. on-task behaviour), cognitive functions (e.g. executive function), and academic achievement (e.g. standardised test scores). Results of the meta-analyses showed classroom-based physical activity had a positive effect on improving on-task and reducing off-task classroom behaviour (standardised mean difference = 0.60 (95% CI: 0.20,1.00)), and led to improvements in academic achievement when a progress monitoring tool was used (standardised mean difference = 1.03 (95% CI: 0.22,1.84)). However, no effect was found for cognitive functions (standardised mean difference = 0.33 (95% CI: -0.11,0.77)) or physical activity (standardised mean difference = 0.40 (95% CI: -1.15,0.95)). CONCLUSIONS: Results suggest classroom-based physical activity may have a positive impact on academic-related outcomes. However, it is not possible to draw definitive conclusions due to the level of heterogeneity in intervention components and academic-related outcomes assessed. Future studies should consider the intervention period when selecting academic-related outcome measures, and use an objective measure of physical activity to determine intervention fidelity and effects on overall physical activity levels

    The genome sequence of the cabbage moth, Mamestra brassicae (Linnaeus, 1758)

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    We present a genome assembly from an individual male Mamestra brassicae (the Cabbage Moth; Arthropoda; Insecta; Lepidoptera; Noctuidae). The genome sequence is 576.2 megabases in span. Most of the assembly is scaffolded into 31 chromosomal pseudomolecules, including the Z sex chromosome. The mitochondrial genome has also been assembled and is 15.38 kilobases in length. Gene annotation of this assembly on Ensembl identified 12,891 protein coding genes

    Effect of CO2 concentrations on entomopathogen fitness and insect-pathogen interactions

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    Numerous insect species and their associated microbial pathogens are exposed to elevated CO2 concentrations in both artificial and natural environments. However, the impacts of elevated CO2 on the fitness of these pathogens and the susceptibility of insects to pathogen infections are not well understood. The yellow mealworm, Tenebrio molitor, is commonly produced for food and feed purposes in mass-rearing systems, which increases risk of pathogen infections. Additionally, entomopathogens are used to control T. molitor, which is also a pest of stored grains. It is therefore important to understand how elevated CO2 may affect both the pathogen directly and impact on host-pathogen interactions. We demonstrate that elevated CO2 concentrations reduced the viability and persistence of the spores of the bacterial pathogen Bacillus thuringiensis. In contrast, conidia of the fungal pathogen Metarhizium brunneum germinated faster under elevated CO2. Pre-exposure of the two pathogens to elevated CO2 prior to host infection did not affect the survival probability of T. molitor larvae. However, larvae reared at elevated CO2 concentrations were less susceptible to both pathogens compared to larvae reared at ambient CO2 concentrations. Our findings indicate that whilst elevated CO2 concentrations may be beneficial in reducing host susceptibility in mass-rearing systems, they may potentially reduce the efficacy of the tested entomopathogens when used as biological control agents of T. molitor larvae. We conclude that CO2 concentrations should be carefully selected and monitored as an additional environmental factor in laboratory experiments investigating insect-pathogen interactions

    Determinants of Change in Physical Activity in Children 0-6 years of Age: A Systematic Review of Quantitative Literature.

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    Background Understanding the determinants of children’s health behaviours is important to develop successful behaviour-change interventions. Objective We aimed to synthesise the evidence around determinants (‘preceding predictors’) of change in physical activity (PA) in young children (0–6 years of age). Methods As part of a suite of reviews, prospective quantitative studies investigating change in physical activity in children aged 0–6 years were identified from eight databases (to October 2015): MEDLINE, Embase, CINAHL, PsycINFO, Web of Knowledge, British Nursing Index, Applied Social Sciences Index and Abstracts, and Sociological Abstracts. Determinants and direction of association were extracted, described and synthesised according to the socio-ecological model (individual, interpersonal, organisational, community, policy). Results Forty-four determinants, predominantly in the interpersonal and organisational domains, were reported across 44 papers (six prospective cohort, 38 interventional); 14 determinants were assessed in four or more papers. Parental monitoring showed a consistent positive association with change in PA; provider training was positively associated with change in children’s moderate-to-vigorous PA only. Five (sex, parental goal setting, social support, motor skill training and increased time for PA) showed no clear association. A further seven (child knowledge, parental knowledge, parental motivation, parenting skills, parental self-efficacy, curriculum materials and portable equipment) were consistently not associated with change in children’s PA. Maternal role-modelling was positively associated with change in PA in all three studies in which it was examined. Conclusions A range of studied determinants of change in young children’s PA were identified, but only parental monitoring was found to be consistently positively associated. More evidence dealing with community and policy domains from low-/middle-income countries and about lesser-explored modifiable family- and childcare-related determinants is required. International Prospective Register for Systematic Reviews (PROSPERO) Registration Number CRD42012002881. Electronic supplementary material The online version of this article (doi:10.1007/s40279-016-0656-0) contains supplementary material, which is available to authorized users

    Thermal ecology shapes disease outcomes of entomopathogenic fungi infecting warm-adapted insects

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    The thermal environment is a critical determinant of outcomes in host-pathogen interactions, yet the complexities of this relationship remain underexplored in many ecological systems. We examined the Thermal Mismatch Hypothesis (TMH) by measuring phenotypic variation in individual thermal performance profiles using a model system of two species of entomopathogenic fungi (EPF) that differ in their ecological niche, Metarhizium brunneum and M. flavoviride, and a warm-adapted model host, the mealworm Tenebrio molitor. We conducted experiments across ecologically relevant temperatures to determine the thermal performance curves for growth and virulence, measured as % survival, identify critical thresholds for these measures, and elucidate interactive host-pathogen effects. Both EPF species and the host exhibited a shared growth optima at 28 °C, while the host’s growth response was moderated in sublethal pathogen infections that depended on fungus identity and temperature. However, variances in virulence patterns were different between pathogens. The fungus M. brunneum exhibited a broader optimal temperature range (23–28 °C) for virulence than M. flavoviride, which displayed a multiphasic virulence-temperature relationship with distinct peaks at 18 and 28 °C. Contrary to predictions of the TMH, both EPF displayed peak virulence at the host's optimal temperature (28 °C). The thermal profile for M. brunneum aligned more closely with that of T. molitor than that for M. flavoviride. Moreover, the individual thermal profile of M. flavoviride closely paralleled its virulence thermal profile, whereas the virulence thermal profile of M. brunneum did not track with its individual thermal performance. This suggests an indirect, midrange (23 °C) effect, where M. brunneum virulence exceeded growth. These findings suggest that the evolutionary histories and ecological adaptations of these EPF species have produced distinct thermal niches during the host interaction. This study contributes to our understanding of thermal ecology in host-pathogen interactions, underpinning the ecological and evolutionary factors that shape infection outcomes in entomopathogenic fungi. The study has ecological implications for insect population dynamics in the face of a changing climate, as well as practically for the use of these organisms in biological control

    Proof of concept and feasibility of the app-based ‘#SWPMoveMore Challenge’: Impacts on physical activity and well-being in a police population

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    An app-based physical activity intervention (#SWPMoveMore Challenge) was completed by 239 workers from one UK police force using a quasi-experimental design. Impacts were assessed against minutes of movement, individual difference and work-related stress variables using quantitative and qualitative approaches. The concept was feasible and translatable to a UK police population and the intervention significantly benefited direct measures of physical activity and perceptions of vitality, job stress, job satisfaction, negative coping strategy use and engagement at work. The intervention was also motivational in helping individuals take-up and maintain physical activity and positively impacted morale and comradery within the work-force
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