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1.
Sci Total Environ ; 747: 141227, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-32781316

RESUMO

Industrial, pre-consumer pellets are a major type of plastics pollution found on shorelines worldwide. This study investigates the distribution and characteristics of plastic pellets accumulated on beaches of the Laurentian Great Lakes of North America and provides a "snapshot" of pellet distribution in a lake system that accounts for 21% of the world's freshwater reserves. We sampled pellets simultaneously from 10m2 quadrats on 66 beaches and characterized the 12,595 pellets collected (average of 19.1 pellets/m2). Forty-two beaches contained pellets and 86% of the pellets were found on three beaches: Rossport (Lake Superior), Baxter (Lake Huron), and Bronte (Lake Ontario). The number of pellets on each beach was compared with factors hypothesized to control their accumulation. In general, positive correlations were found between pellet abundance and watershed population, number of plastic-related industries, and proximity to a river mouth, although for Lake Superior, abundance was related to a train spill that took place over 10 years ago. Beach grain size appears to be related to pellet abundance, with very fine sand, fine sand and medium sand containing the greatest number of pellets. All pellets were visually characterized based on size, color, shape, weathering, and distinguishing traits. The predominant color was white, oblate shapes were most common, and the main distinguishing trait was a dimple. Most pellets showed little evidence of weathering, with the weathered samples mainly from Lakes Erie and Ontario. Lake Ontario pellets were the most varied, with 6/7 shapes, 35/40 colors, and 21/25 distinguishing traits, indicating a wider range of pellet sources compared to the other lakes. Polymer compositions were mainly polyethylene (PE) and polypropylene (PP). Our results will lead to increased recognition of regional pellet pollution in the Great Lakes watershed, thereby motivating change during their production, transport and use.

2.
Nat Ecol Evol ; 3(3): 363-373, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30643247

RESUMO

Urban areas are often perceived to have lower biodiversity than the wider countryside, but a few small-scale studies suggest that some urban land uses can support substantial pollinator populations. We present a large-scale, well-replicated study of floral resources and pollinators in 360 sites incorporating all major land uses in four British cities. Using a systems approach, we developed Bayesian network models integrating pollinator dispersal and resource switching to estimate city-scale effects of management interventions on plant-pollinator community robustness to species loss. We show that residential gardens and allotments (community gardens) are pollinator 'hotspots': gardens due to their extensive area, and allotments due to their high pollinator diversity and leverage on city-scale plant-pollinator community robustness. Household income was positively associated with pollinator abundance in gardens, highlighting the influence of socioeconomic factors. Our results underpin urban planning recommendations to enhance pollinator conservation, using increasing city-scale community robustness as our measure of success.


Assuntos
Conservação dos Recursos Naturais/métodos , Polinização , Teorema de Bayes , Biodiversidade , Cidades , Inglaterra , Escócia , Análise de Sistemas
3.
Ambio ; 48(8): 855-866, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30448996

RESUMO

This paper considers how an interdisciplinary approach to the "wicked problem" of plastics pollution offers unique and important collaborative possibilities. Specially, the paper considers the approach of the Synthetic Collective, a group comprising artists, humanities scholars, and scientists. Considering first how artists and scientists might respond differently to tracking, mapping, understanding, and representing plastics pollution, we then look for potential points of commonality across disciplinary difference. In respect to the urgent and multifaceted problem of marine plastics pollution in the Great Lakes region, we ask what are some of the successes and pitfalls of bringing together diverse approaches and interests? The paper concludes with a clear strategy: a set of instructions geared towards building successful interdisciplinary collaborations. Ultimately, we conclude that a strong relationship amongst scientists and artists is possible, fruitful, and indeed warranted when shared goals are the driving principle of the group.


Assuntos
Estudos Interdisciplinares , Plásticos , Poluição Ambiental , Great Lakes Region , Ciências Humanas
4.
Int J Cardiol Heart Vasc ; 18: 65-70, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29876506

RESUMO

BACKGROUND: Families of children at the worst end of the congenital heart disease endure a significant burden which is often not clearly delineated in the clinical literature. We examined the greatest concerns of parents whose children have a Fontan circulation. METHODS: Parents (N = 107) of children in the Australian and New Zealand Fontan Registry completed online surveys with open-ended and closed questions. A qualitative method approach incorporating thematic analyses was used. RESULTS: The greatest concerns for parents of a child with a Fontan circulation were centered on fear of death for their child and psychosocial well-being, followed by lesser themes around anti-coagulation use, pregnancy and financial burdens. CONCLUSIONS: Fear of death and the psychological well-being of their children were the main parental concerns. It highlights the need to clearly communicate information on outcomes to families, and the need for family-focused psychological interventions to improve the psychosocial functioning of both parents and young people.

5.
Int J Cardiol ; 260: 54-59, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29622455

RESUMO

BACKGROUND: Little is known about adults living with a Fontan circulation's concerns outside the scope of their clinical outcomes. We examined adults with a Fontan circulations' greatest concerns, as well as their concerns around anti-coagulation, pregnancy and finances. METHODS: Adults with a Fontan circulation in the Australian and New Zealand Fontan Registry were invited to complete an anonymous online survey, of which 57 participated. A qualitative method approach using thematic analyses was used. RESULTS: The greatest concerns for adults living with a Fontan circulation were fear of death/uncertainty around life expectancy which for many individuals colored their concerns around physical health, pregnancy and having children, quality of life and finances. Improving information about outcomes to patients with a Fontan circulation might alleviate uncertainties about their future. CONCLUSIONS: Fear of death is the primary concern of adults with a Fontan circulation. It may require improved communication and targeted psychological interventions. Physical exercise incorporated as part of their lifestyle should be encouraged to alleviate physical concerns and also improve psychological well-being.


Assuntos
Medo/psicologia , Técnica de Fontan/psicologia , Técnica de Fontan/tendências , Autorrelato , Adolescente , Adulto , Austrália/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Sistema de Registros , Fatores de Tempo , Adulto Jovem
6.
PLoS One ; 11(6): e0158117, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27341588

RESUMO

Planted meadows are increasingly used to improve the biodiversity and aesthetic amenity value of urban areas. Although many 'pollinator-friendly' seed mixes are available, the floral resources these provide to flower-visiting insects, and how these change through time, are largely unknown. Such data are necessary to compare the resources provided by alternative meadow seed mixes to each other and to other flowering habitats. We used quantitative surveys of over 2 million flowers to estimate the nectar and pollen resources offered by two exemplar commercial seed mixes (one annual, one perennial) and associated weeds grown as 300m2 meadows across four UK cities, sampled at six time points between May and September 2013. Nectar sugar and pollen rewards per flower varied widely across 65 species surveyed, with native British weed species (including dandelion, Taraxacum agg.) contributing the top five nectar producers and two of the top ten pollen producers. Seed mix species yielding the highest rewards per flower included Leontodon hispidus, Centaurea cyanus and C. nigra for nectar, and Papaver rhoeas, Eschscholzia californica and Malva moschata for pollen. Perennial meadows produced up to 20x more nectar and up to 6x more pollen than annual meadows, which in turn produced far more than amenity grassland controls. Perennial meadows produced resources earlier in the year than annual meadows, but both seed mixes delivered very low resource levels early in the year and these were provided almost entirely by native weeds. Pollen volume per flower is well predicted statistically by floral morphology, and nectar sugar mass and pollen volume per unit area are correlated with flower counts, raising the possibility that resource levels can be estimated for species or habitats where they cannot be measured directly. Our approach does not incorporate resource quality information (for example, pollen protein or essential amino acid content), but can easily do so when suitable data exist. Our approach should inform the design of new seed mixes to ensure continuity in floral resource availability throughout the year, and to identify suitable species to fill resource gaps in established mixes.


Assuntos
Biodiversidade , Flores , Néctar de Plantas , Pólen , Animais , Abelhas , Ecossistema , Alimentos , Polinização , Estações do Ano , Sementes
7.
Proc Biol Sci ; 282(1803): 20142849, 2015 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-25673686

RESUMO

Insect pollinators provide a crucial ecosystem service, but are under threat. Urban areas could be important for pollinators, though their value relative to other habitats is poorly known. We compared pollinator communities using quantified flower-visitation networks in 36 sites (each 1 km(2)) in three landscapes: urban, farmland and nature reserves. Overall, flower-visitor abundance and species richness did not differ significantly between the three landscape types. Bee abundance did not differ between landscapes, but bee species richness was higher in urban areas than farmland. Hoverfly abundance was higher in farmland and nature reserves than urban sites, but species richness did not differ significantly. While urban pollinator assemblages were more homogeneous across space than those in farmland or nature reserves, there was no significant difference in the numbers of rarer species between the three landscapes. Network-level specialization was higher in farmland than urban sites. Relative to other habitats, urban visitors foraged from a greater number of plant species (higher generality) but also visited a lower proportion of available plant species (higher specialization), both possibly driven by higher urban plant richness. Urban areas are growing, and improving their value for pollinators should be part of any national strategy to conserve and restore pollinators.


Assuntos
Biodiversidade , Ecossistema , Insetos/fisiologia , Polinização/fisiologia , Agricultura , Animais , Abelhas/fisiologia , Cidades , Dípteros/fisiologia , Magnoliopsida/fisiologia , Reino Unido
8.
Accid Anal Prev ; 50: 905-16, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22878143

RESUMO

Previous research on the theory of planned behavior (TPB) is characterized by cross-sectional tests of the model's proposed causal relationships. In the absence of effective experimental techniques for changing the TPB's cognitive antecedents, the present research aimed to provide a stronger non-experimental test of the model, using causal analyses of two-wave panel data. Two studies of driver behavior were conducted in which naturally occurring within-participant changes in TPB constructs were measured over time, and used to predict corresponding within-participant changes in both intentions and behavior. A two-wave panel design was used in both studies. Study 1 had a one-month gap between baseline and follow-up. At both waves, a convenience sample comprising predominantly university students (N=135) completed questionnaire measures of all TPB cognitions and behavior (compliance with speed limits in urban areas). Cross-lagged multiple regressions and bootstrapping procedures for testing multiple mediators supported all of the relationships proposed by the TPB. These findings were extended in study 2 using a large, non-student sample of speed limit offenders (N=1149), a six-month gap between baseline and follow-up, and a larger number of cognitive antecedents. Participants completed postal questionnaires at both waves to measure all cognitions proposed by the two-component TPB, along with moral norm, anticipated regret, self-identity and speeding on urban roads, country roads, and fast dual carriageways or motorways. Changes in instrumental and affective attitude, descriptive norm, self-efficacy, moral norm, anticipated regret and self-identity predicted changes in intention to speed. Changes in intention and self-efficacy predicted behavior-change. Injunctive norm and perceived controllability did not predict intention or behavior-change. Additionally, direct (unhypothesized) relationships with behavior were found for affective attitude, descriptive norm and anticipated regret. The implications of the findings for theory and the development of effective behavior-change interventions are discussed.


Assuntos
Condução de Veículo/psicologia , Cognição , Comportamento Social , Aceleração , Adolescente , Adulto , Idoso , Causalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escócia , Inquéritos e Questionários
9.
Biochim Biophys Acta ; 1639(3): 203-12, 2003 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-14636952

RESUMO

The anti-atherogenic effect of HDL has been suggested to be partly due to the action of HDL-associated paraoxonase (PON). Three distinct enzymes have been identified, encoded by PON1, PON2 and PON3, clustered on chromosome 7q21-q22. Two cSNPs in PON1 (L55M and Q192R) and one in PON2 (S311C) have been implicated as independent risk factors for coronary heart disease (CHD) in some, but not all, studies. A PON3 SNP (A99A) was identified and the effect of these four PON SNPs on HDL levels and CHD risk was examined in the prospective Northwick Park Heart Study II (NPHSII). Genotype frequencies did not differ between cases and controls but the CHD risk associated with smoking was significantly modified by PON1 L55M genotype. Compared to LL non-smokers, LL smokers had a hazard ratio (HR) of 1.30 (95% CI 0.81-2.06) while M-allele carriers had a HR of 1.76 (1.17-2.67). When genotypes were analysed in combination, men with the genotype PON1 55 LM/MM+PON2 311 CC, had HR of 3.54 (1.81-6.93) compared to PON1 LL+PON2 SS/SC men (interaction P=0.004). These effects were independent of classical risk factors. These data demonstrate the importance of stratifying by environmental factors and the use of multiple SNPs for genetic analysis.


Assuntos
Arildialquilfosfatase/genética , Cromossomos Humanos Par 7 , Doença das Coronárias/epidemiologia , Família Multigênica , Polimorfismo Genético , Substituição de Aminoácidos , Mapeamento Cromossômico , Doença das Coronárias/enzimologia , Doença das Coronárias/genética , Genótipo , Humanos , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Fumar , Fatores de Tempo , População Branca
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