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1.
J Hazard Mater ; 453: 131392, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37086672

RESUMO

Microplastics are a prolific environmental contaminant. Curbing microplastic pollution requires an array of globally relevant interventions, including source-reduction and curative measures. A novel, nature-based solution to microplastics is proposed, in which mussels are deployed in aquatic ecosystems to act as microplastic biofilters, removing waterborne microplastics and repackaging them into biodeposits that are subsequently captured and removed. Blue mussels (Mytilus edulis) were used to establish the feasibility of such an approach. In the laboratory, mussels were exposed to representative microplastics in a flume tank; at an initial concentration of 1000 microplastics L-1, mussels reduced waterborne microplastic concentrations at an average rate of 40,146 microplastics kg-1 h-1. Mussel faeces sank irrespective of microplastic content, with average sinking velocities of 223-266 m day-1. Modelling predicts ∼3 × 109 mussels deployed on ropes at the mouths of estuaries could remove 4% of waterborne microplastics discharged from rivers. Mussels were successfully deployed in a prototype biodeposit collection system in an urban marina, with 5.0 kg of mussels removing and repackaging 239.9 ± 145.9 microplastics and anthropogenic particles day-1 into their faeces. These results provide impetus for further development of nature-based solutions targeting plastic debris.


Assuntos
Microplásticos , Mytilus edulis , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental/métodos , Plásticos , Poluentes Químicos da Água/análise , Recuperação e Remediação Ambiental/métodos
2.
Environ Pollut ; 268(Pt A): 115754, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33032097

RESUMO

Antifouling paint particles (APPs) and associated metals have been identified in sediments around boatyards and marinas globally, but the effects of APPs on benthic organisms are largely unknown. Sub-lethal endpoints were measured following laboratory exposures of the harbour ragworm (Hediste diversicolor) and the common cockle (Cerastoderma edule) to environmentally relevant concentrations of biocidal ('modern' and 'historic') and biocide-free ('silicone') APPs added to clean estuarine sediment. Further, the 5-day median lethal concentrations (LC50) and effects concentrations (EC50) for modern biocidal APPs were calculated. For ragworms, significant decreases in weight (15.7%; p < 0.01) and feeding rate (10.2%; p < 0.05) were observed in the modern biocidal treatment; burrowing behaviour was also reduced by 29% in this treatment, but was not significant. For cockles, the modern biocidal treatment led to 100% mortality of all replicates before endpoints were measured. In cockles, there was elevated levels of metallothionein-like protein (MTLP) in response to both modern and historic biocidal treatments. Ragworms had a higher tolerance to modern APPs (5-day LC50:19.9 APP g L-1; EC50: 14.6 g L-1) compared to cockles (5-day LC50: 2.3 g L-1 and EC50: 1.4 g L-1). The results of this study indicate that modern biocidal APPs, containing high Cu concentrations, have the potential to adversely affect the health of benthic organisms at environmentally relevant concentrations. The findings highlight the need for stricter regulations on the disposal of APP waste originating from boatyards, marinas and abandoned boats.


Assuntos
Poliquetos , Poluentes Químicos da Água , Animais , Sedimentos Geológicos , Invertebrados , Metais/análise , Pintura/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
3.
Sci Rep ; 10(1): 12161, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699214

RESUMO

Rates and drivers of primary productivity are well understood for many terrestrial ecosystems, but remain poorly resolved for many marine ecosystems, particularly those within in coastal benthic environments. We quantified net primary productivity (NPP) using two methods as well as carbon standing stock within kelp forests (Laminaria hyperborea) at multiple subtidal habitats in the United Kingdom (UK). Study sites spanned 9° in latitude and encompassed a gradient in average temperature of ~ 2.5 °C. In addition to temperature, we measured other factors (e.g. light intensity, water motion, nutrients, sea urchin density) that may influence productivity. Although estimates of NPP were highly variable between sites, ranging from 166 to 738 g C m-2 yr-1, our study-wide average of 340 g C m-2 yr-1 indicated that L. hyperborea forests are highly productive. We observed clear differences between NPP and carbon standing stock between our cold northernmost sites and our warm southernmost sites, with NPP and standing stock being around 1.5 and 2.5 times greater in the northern sites, respectively. Ocean temperature was identified as a likely driver of productivity, with reduced NPP and standing stock observed in warmer waters. Light availability was also strongly linked with carbon accumulation and storage, with increased light levels positively correlated with NPP and standing stock. Across its geographical range, total NPP from L. hyperborea is estimated at ~ 7.61 Tg C yr-1. This biomass production is likely to be important for local food webs, as a trophic subsidy to distant habitats and for inshore carbon cycling and (potentially) carbon sequestration. However, given the strong links with temperature, continued ocean warming in the northeast Atlantic may reduce primary productivity of this foundation species, as optimal temperatures for growth and performance are surpassed.


Assuntos
Ecossistema , Laminaria/crescimento & desenvolvimento , Animais , Oceano Atlântico , Biomassa , Carbono/metabolismo , Ciclo do Carbono , Cadeia Alimentar , Laminaria/metabolismo , Luz , Ouriços-do-Mar/crescimento & desenvolvimento , Temperatura
4.
PeerJ ; 3: e863, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25834773

RESUMO

Extreme climatic events, including heat waves (HWs) and severe storms, influence the structure of marine and terrestrial ecosystems. Despite growing consensus that anthropogenic climate change will increase the frequency, duration and magnitude of extreme events, current understanding of their impact on communities and ecosystems is limited. Here, we used sessile invertebrates on settlement panels as model assemblages to examine the influence of HW magnitude, duration and timing on marine biodiversity patterns. Settlement panels were deployed in a marina in southwest UK for ≥5 weeks, to allow sufficient time for colonisation and development of sessile fauna, before being subjected to simulated HWs in a mesocosm facility. Replicate panel assemblages were held at ambient sea temperature (∼17 °C), or +3 °C or +5 °C for a period of 1 or 2 weeks, before being returned to the marina for a recovery phase of 2-3 weeks. The 10-week experiment was repeated 3 times, staggered throughout summer, to examine the influence of HW timing on community impacts. Contrary to our expectations, the warming events had no clear, consistent impacts on the abundance of species or the structure of sessile assemblages. With the exception of 1 high-magnitude long-duration HW event, warming did not alter not assemblage structure, favour non-native species, nor lead to changes in richness, abundance or biomass of sessile faunal assemblages. The observed lack of effect may have been caused by a combination of (1) the use of relatively low magnitude, realistic heat wave treatments compared to previous studies (2), the greater resilience of mature adult sessile fauna compared to recruits and juveniles, and (3) the high thermal tolerance of the model organisms (i.e., temperate fouling species, principally bryozoans and ascidians). Our study demonstrates the importance of using realistic treatments when manipulating climate change variables, and also suggests that biogeographical context may influence community-level responses to short-term warming events, which are predicted to increase in severity in the future.

5.
PLoS One ; 6(5): e19514, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21611170

RESUMO

Species richness is the most commonly used but controversial biodiversity metric in studies on aspects of community stability such as structural composition or productivity. The apparent ambiguity of theoretical and experimental findings may in part be due to experimental shortcomings and/or heterogeneity of scales and methods in earlier studies. This has led to an urgent call for improved and more realistic experiments. In a series of experiments replicated at a global scale we translocated several hundred marine hard bottom communities to new environments simulating a rapid but moderate environmental change. Subsequently, we measured their rate of compositional change (re-structuring) which in the great majority of cases represented a compositional convergence towards local communities. Re-structuring is driven by mortality of community components (original species) and establishment of new species in the changed environmental context. The rate of this re-structuring was then related to various system properties. We show that availability of free substratum relates negatively while taxon richness relates positively to structural persistence (i.e., no or slow re-structuring). Thus, when faced with environmental change, taxon-rich communities retain their original composition longer than taxon-poor communities. The effect of taxon richness, however, interacts with another aspect of diversity, functional richness. Indeed, taxon richness relates positively to persistence in functionally depauperate communities, but not in functionally diverse communities. The interaction between taxonomic and functional diversity with regard to the behaviour of communities exposed to environmental stress may help understand some of the seemingly contrasting findings of past research.


Assuntos
Biodiversidade , Internacionalidade , Invertebrados/crescimento & desenvolvimento , Água do Mar , Animais , Dinâmica Populacional , Especificidade da Espécie
6.
Chem Commun (Camb) ; (11): 1386-8, 2009 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-19259596

RESUMO

A substantial set of ion-driven molecular logic gates are implemented in turn by arranging the association between easily available lumophores and receptors in detergent micelles.

7.
Prog Community Health Partnersh ; 3(4): 359-63, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20097997

RESUMO

African and Latino Americans have higher rates of diabetes and its complications than White Americans. Identifying people with undiagnosed diabetes and helping them obtain care can help to prevent complications and mortality. To kick off a screening initiative, our community-academic partnership created the "Food for Life Festival," or "Festival Comida para la Vida." This article will describe the community's perspective on the Festival, which was designed to screen residents, and demonstrate that eating healthy can be fun, tasty, and affordable in a community-centered, culturally consonant setting. More than 1,000 residents attended the event; 382 adults were screened for diabetes, and 181 scored as high risk. Fifteen restaurants distributed free samples of healthy versions of their popular dishes. Community residents, restaurateurs, and clinicians commented that the event transformed many of their preconceived ideas about healthy foods and patient care.


Assuntos
Conscientização , Diabetes Mellitus/prevenção & controle , Comportamento Alimentar , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde/métodos , Férias e Feriados , Negro ou Afro-Americano , Comportamento Cooperativo , Diabetes Mellitus/epidemiologia , Feminino , Educação em Saúde , Hispânico ou Latino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Marketing Social , Estados Unidos/epidemiologia
8.
Org Biomol Chem ; 6(14): 2468-80, 2008 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-18600265

RESUMO

Using cartoons as an organizational aid, we illustrate how the 'fluorophore-spacer-receptor' format of fluorescent PET (photoinduced electron transfer) sensors and switches can be logically extended in many different directions. These include emissive sensors for various chemical species and properties, and exploit various kinds of emission. Common sensing issues such as dynamic range, internal referencing, selectivity, mapping and space resolution are addressed. The sensory output function is also developed into more complex forms, molecular logic/computation being one such example. Molecular logic leads to molecular arithmetic. Real-life applications to physiological monitoring, medical diagnostics and molecular computational identification of small objects are included.

9.
Mt Sinai J Med ; 75(1): 13-21, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18306238

RESUMO

OBJECTIVE: Diabetes prevalence and mortality are increasing, with minority populations disproportionately affected. Despite evidence that weight loss due to improved nutrition and increased physical activity can prevent or control diabetes, there is often a disconnect between this evidence and individuals' lifestyles. METHODS: East Harlem is a predominantly African-American and Latino neighborhood that has the highest rates of diabetes prevalence and mortality in New York City. The East Harlem Diabetes Center of Excellence is a community-centered coalition. To help direct their work, the coalition used their experiences, research, outreach, and literature review to build a conceptual model describing how local factors affect health behaviors and health outcomes such as obesity and diabetes. RESULTS: This model describes the relationship between the physical environment, the social/medical environment and individual factors including demographic data, food and exercise beliefs and behaviors, and health outcomes. The coalition inserted local data from surveys and focus groups into the model to identify targets for future interventions, research, and activism. CONCLUSIONS: This type of collaboration and the model may be useful tools to help communities identify and address the deficits that prevent their residents from enjoying the health benefits of improved nutrition and increased physical activity, and that also lead to racial and ethnic disparities in health.


Assuntos
Planejamento em Saúde Comunitária , Diabetes Mellitus/epidemiologia , Surtos de Doenças , Estado Nutricional , Participação do Paciente , Características de Residência , Adulto , Negro ou Afro-Americano , Comportamento Cooperativo , Diabetes Mellitus/mortalidade , Estudos Epidemiológicos , Feminino , Grupos Focais , Inquéritos Epidemiológicos , Hispânico ou Latino , Humanos , Masculino , Atividade Motora , Cidade de Nova Iorque/epidemiologia , Prevalência , Meio Social
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