1,135 research outputs found
Functional richness and identity do not strongly affect invasibility of constructed dune communities
© 2017 Mason et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Biotic effects are often used to explain community structure and invasion resistance. We evaluated the contribution of functional richness and identity to invasion resistance and abiotic resource availability using a mesocosm experiment. We predicted that higher functional richness would confer greater invasion resistance through greater resource sequestration. We also predicted that niche pre-emption and invasion resistance would be higher in communities which included functional groups similar to the invader than communities where all functional groups were distinct from the invader. We constructed communities of different functional richness and identity but maintained constant species richness and numbers of individuals in the resident community. The constructed communities represented potential fore dune conditions following invader control activities along the Australian east coast. We then simulated an invasion event by bitou (Chrysanthemoides monilifera ssp. rotundata DC. Norl.), a South African shrub invader. We used the same bitou propagule pressure across all treatments and monitored invasion success and resource availability for 13 months. Contrary to our predictions, we found that functional richness did not mediate the number of bitou individuals or bitou cover and functional identity had little effect on invasion success: there was a trend for the grass single functional group treatment to supress bitou individuals, but this trend was obscured when grasses were in multi functional group treatments. We found that all constructed communities facilitated bitou establishment and suppressed bitou cover relative to unplanted mesocosms. Abiotic resource use was either similar among planted communities, or differences did not relate to invasion success (with the exception of light availability). We attribute invasion resistance to bulk plant biomass across planted treatments rather than their functional group arrangement
8th International Conference: Primary Therapy of Early Breast Cancer, St Gallen, Switzerland, March 12–15 2003
The International St Gallen Breast Cancer Conference concentrates almost exclusively on adjuvant, multimodal primary therapy for early breast cancer. Begun 25 years ago, this meeting was initially held every 4 years, but therapeutic progress, new strategies and provocative trials data have accelerated to the extent that conferences are now held biennially. The meeting this year was attended by almost 3000 delegates. Major topics included new prognostic and predictive markers in early breast cancer, the best use of adjuvant chemotherapy and endocrine therapy, and innovations in local surgery and radiation therapy
Reducing unhealthy weight gain in children through community capacity−building: results of a quasi−experimental intervention program, Be Active Eat Well
Background:Be Active Eat Well (BAEW) was a multifaceted community capacity-building program promoting healthy eating and physical activity for children (aged 4–12 years) in the Australian town of Colac.Objective:To evaluate the effects of BAEW on reducing children\u27s unhealthy weight gain.Methods:BAEW had a quasi-experimental, longitudinal design with anthropometric and demographic data collected on Colac children in four preschools and six primary schools at baseline (2003, n=1001, response rate: 58%) and follow-up (2006, n=839, follow-up rate: 84%). The comparison sample was a stratified random selection of preschools (n=4) and primary schools (n=12) from the rest of the Barwon South Western region of Victoria, with baseline assessment in 2003–2004 (n=1183, response rate: 44%) and follow-up in 2006 (n=979, follow-up rate: 83%).Results:Colac children had significantly lower increases in body weight (mean: -0.92 kg, 95% CI: -1.74 to -0.11), waist (-3.14 cm, -5.07 to -1.22), waist/height (-0.02, -0.03 to -0.004), and body mass index z-score (-0.11, -0.21 to -0.01) than comparison children, adjusted for baseline variable, age, height, gender, duration between measurements and clustering by school. In Colac, the anthropometric changes were not related to four indicators of socioeconomic status (SES), whereas in the comparison group 19/20 such analyses showed significantly greater gains in anthropometry in children from lower SES families. Changes in underweight and attempted weight loss were no different between the groups.Conclusions:Building community capacity to promote healthy eating and physical activity appears to be a safe and effective way to reduce unhealthy weight gain in children without increasing health inequalities.<br /
‘Do i care?’ young adults' recalled experiences of early adolescent overweight and obesity: a qualitative study
<p>Objective: Individual behaviour change to reduce obesity requires awareness of, and concern about, weight. This paper therefore describes how young adults, known to have been overweight or obese during early adolescence, recalled early adolescent weight-related awareness and concerns. Associations between recalled concerns and weight-, health- and peer-related survey responses collected during adolescence are also examined.</p>
<p>Design: Qualitative semi-structured interviews with young adults; data compared with responses to self-report questionnaires obtained in adolescence.</p>
<p>Participants: A total of 35 participants, purposively sub-sampled at age 24 from a longitudinal study of a school year cohort, previously surveyed at ages 11, 13 and 15. Physical measures during previous surveys allowed identification of participants with a body mass index (BMI) indicative of overweight or obesity (based on British 1990 growth reference) during early adolescence. Overall, 26 had been obese, of whom 11 had BMI99.6th centile, whereas 9 had been overweight (BMI=95th–97.9th centile).</p>
<p>Measures: Qualitative interview responses describing teenage life, with prompts for school-, social- and health-related concerns. Early adolescent self-report questionnaire data on weight-worries, self-esteem, friends and victimisation (closed questions).</p>
<p>Results: Most, but not all recalled having been aware of their overweight. None referred to themselves as having been obese. None recalled weight-related health worries. Recollection of early adolescent obesity varied from major concerns impacting on much of an individual's life to almost no concern, with little relation to actual severity of overweight. Recalled concerns were not clearly patterned by gender, but young adult males recalling concerns had previously reported more worries about weight, lower self-esteem, fewer friends and more victimisation in early adolescence; no such pattern was seen among females.
Conclusion: The popular image of the unhappy overweight teenager was not borne out. Many obese adolescents, although well aware of their overweight recalled neither major dissatisfaction nor concern. Weight-reduction behaviours are unlikely in such circumstances.</p>
Community Health Environment Scan Survey (CHESS): a novel tool that captures the impact of the built environment on lifestyle factors
Background: Novel1 1This study was performed on behalf of the Community Interventions for Health (CIH) collaboration. efforts and accompanying tools are needed to tackle the global burden of chronic disease. This paper presents an approach to describe the environments in which people live, work, and play. Community Health Environment Scan Survey (CHESS) is an empirical assessment tool that measures the availability and accessibility, of healthy lifestyle options lifestyle options. CHESS reveals existing community assets as well as opportunities for change, shaping community intervention planning efforts by focusing on community-relevant opportunities to address the three key risk factors for chronic disease (i.e. unhealthy diet, physical inactivity, and tobacco use). Methods: The CHESS tool was developed following a review of existing auditing tools and in consultation with experts. It is based on the social-ecological model and is adaptable to diverse settings in developed and developing countries throughout the world. Results: For illustrative purposes, baseline results from the Community Interventions for Health (CIH) Mexico site are used, where the CHESS tool assessed 583 food stores and 168 restaurants. Comparisons between individual-level survey data from schools and community-level CHESS data are made to demonstrate the utility of the tool in strategically guiding intervention activities. Conclusion: The environments where people live, work, and play are key factors in determining their diet, levels of physical activity, and tobacco use. CHESS is the first tool of its kind that systematically and simultaneously examines how built environments encourage/discourage healthy eating, physical activity, and tobacco use. CHESS can help to design community interventions to prevent chronic disease and guide healthy urban planning
Positive Interspecific Relationship between Temporal Occurrence and Abundance in Insects
One of the most studied macroecological patterns is the interspecific abundance–occupancy relationship, which relates species distribution and abundance across space. Interspecific relationships between temporal distribution and abundance, however, remain largely unexplored. Using data for a natural assemblage of tabanid flies measured daily during spring and summer in Nova Scotia, we found that temporal occurrence (proportion of sampling dates in which a species occurred in an experimental trap) was positively related to temporal mean abundance (number of individuals collected for a species during the study period divided by the total number of sampling dates). Moreover, two models that often describe spatial abundance–occupancy relationships well, the He–Gaston and negative binomial models, explained a high amount of the variation in our temporal data. As for the spatial abundance–occupancy relationship, the (temporal) aggregation parameter, k, emerged as an important component of the hereby named interspecific temporal abundance–occurrence relationship. This may be another case in which a macroecological pattern shows similarities across space and time, and it deserves further research because it may improve our ability to forecast colonization dynamics and biological impacts
Consequences of converting graded to action potentials upon neural information coding and energy efficiency
Information is encoded in neural circuits using both graded and action potentials, converting between them within single neurons and successive processing layers. This conversion is accompanied by information loss and a drop in energy efficiency. We investigate the biophysical causes of this loss of information and efficiency by comparing spiking neuron models, containing stochastic voltage-gated Na+ and K+ channels, with generator potential and graded potential models lacking voltage-gated Na+ channels. We identify three causes of information loss in the generator potential that are the by-product of action potential generation: (1) the voltage-gated Na+ channels necessary for action potential generation increase intrinsic noise and (2) introduce non-linearities, and (3) the finite duration of the action potential creates a ‘footprint’ in the generator potential that obscures incoming signals. These three processes reduce information rates by ~50% in generator potentials, to ~3 times that of spike trains. Both generator potentials and graded potentials consume almost an order of magnitude less energy per second than spike trains. Because of the lower information rates of generator potentials they are substantially less energy efficient than graded potentials. However, both are an order of magnitude more efficient than spike trains due to the higher energy costs and low information content of spikes, emphasizing that there is a two-fold cost of converting analogue to digital; information loss and cost inflation
Social marketing and healthy eating : Findings from young people in Greece
This document is the Accepted Manuscript version. The final publication is available at Springer via http://dx.doi.org/10.1007/s12208-013-0112-xGreece has high rates of obesity and non-communicable diseases owing to poor dietary choices. This research provides lessons for social marketing to tackle the severe nutrition-related problems in this country by obtaining insight into the eating behaviour of young adults aged 18–23. Also, the main behavioural theories used to inform the research are critically discussed. The research was conducted in Athens. Nine focus groups with young adults from eight educational institutions were conducted and fifty-nine participants’ views towards eating habits, healthy eating and the factors that affect their food choices were explored. The study found that the participants adopted unhealthier nutritional habits after enrolment. Motivations for healthy eating were good health, appearance and psychological consequences, while barriers included lack of time, fast-food availability and taste, peer pressure, lack of knowledge and lack of family support. Participants reported lack of supportive environments when deciding on food choices. Based on the findings, recommendations about the development of the basic 4Ps of the marketing mix, as well as of a fifth P, for Policy are proposedPeer reviewe
Effect of prenatal glucocorticoid treatment on size at birth among infants born at term gestation
ObjectiveTo determine whether prenatal treatment with a single course of glucocorticoids (GCs) affects size at birth among full-term infants independent of fetal size before GC administration or exposure to preterm labor (PTL).Study designIn all, 105 full-term infants were recruited into three study groups (30 GC treated; 60 controls matched for gestational age (GA) at birth and sex; and 15 PTL controls without GC exposure). Size of the infants was estimated before treatment using two-dimensional (2D) ultrasound and by direct measurement at birth.ResultsLength, weight and head circumference at birth were smaller among GC-treated infants compared with matched controls (P's<0.01), although fetal size did not differ before treatment (P's>0.2). Exposure to PTL did not account for this effect.ConclusionsPrenatal treatment with a single course of GCs was associated with a reduction in size at birth among infants born at term gestation. This effect cannot be explained by differences in fetal size before treatment or exposure to PTL
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