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1.
Environ Pollut ; 313: 120171, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36113647

RESUMO

The immense production of plastic polymers combined with their discordancy with nature has led to vast plastic waste contamination across the geosphere, from the oceans to freshwater reservoirs, wetlands, remote snowpacks, sediments, air and multiple other environments. These environmental pollutants include microplastics (MP), typically defined as small and fragmented plastics less than 5 mm in size, and nanoplastics (NP), particles smaller than a micrometer. The formation of micro and nanoplastics in aqueous media to date has been largely attributed to fragmentation of plastics by natural (i.e., abrasion, photolysis, biotic) or industrial processes. We present a novel method to create small microplastics (≲ 5 µm) and nanoplastics in water from a wide variety of plastic materials using a small volume of a solubilizer liquid, such as n-dodecane, in combination with vigorous mixing. When the suspensions or solutions are subjected to ultrasonic mixing, the particle sizes decrease. Small micro- and nanoparticles were made from commercial, real world and waste (aged) polyethylene, polystyrene, polycarbonate and polyethylene terephthalate, in addition to other plastic materials and were analyzed using dark field microscopy, Raman spectroscopy and particle size measurements. The presented method provides a new and simple way to create specific size distributions of micro- and nanoparticles, which will enable expanded research on these plastic particles in water, especially those made from real world and aged plastics. The ease of NP and small MP formation upon initial mixing simulates real world environments, thereby providing further insight into the behavior of plastics in natural settings.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Microplásticos , Plásticos , Polietileno , Polietilenotereftalatos , Poliestirenos , Suspensões , Água , Poluentes Químicos da Água/análise
2.
Conserv Biol ; 36(3): e13845, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34622490

RESUMO

Biodiversity loss is driven by human behavior, but there is uncertainty about the effectiveness of behavior-change programs in delivering benefits to biodiversity. To demonstrate their value, the biodiversity benefits and cost-effectiveness of behavior changes that directly or indirectly affect biodiversity need to be quantified. We adapted a structured decision-making prioritization tool to determine the potential biodiversity benefits of behavior changes. As a case study, we examined two hypothetical behavior-change programs--wildlife gardening and cat containment--by asking experts to consider the behaviors associated with these programs that directly and indirectly affect biodiversity. We assessed benefits to southern brown bandicoot (Isoodon obesulus) and superb fairy-wren (Malurus cyaneus) by eliciting from experts estimates of the probability of each species persisting in the landscape given a range of behavior-change scenarios in which uptake of the behaviors varied. We then compared these estimates to a business-as-usual scenario to determine the relative biodiversity benefit and cost-effectiveness of each scenario. Experts projected that the behavior-change programs would benefit biodiversity and that benefits would rise with increasing uptake of the target behaviors. Biodiversity benefits were also predicted to accrue through indirect behaviors, although experts disagreed about the magnitude of additional benefit provided. Scenarios that combined the two behavior-change programs were estimated to provide the greatest benefits to species and be most cost-effective. Our method could be used in other contexts and potentially at different scales and advances the use of prioritization tools to guide conservation behavior-change programs.


Proyección de los beneficios para la biodiversidad obtenidos de los programas de cambios de comportamiento de conservación Resumen La pérdida de la diversidad biológica es causada por el comportamiento humano, pero existe incertidumbre sobre la efectividad que tienen los programas de cambio de comportamiento para otorgar beneficios a la biodiversidad. Para demostrar el valor que poseen, los beneficios para la biodiversidad y la rentabilidad de los cambios de comportamiento que afectan directa o indirectamente a la biodiversidad necesitan ser cuantificados. Adaptamos una herramienta de priorización de toma de decisiones estructurada para determinar el potencial de los beneficios para la biodiversidad obtenidos de los cambios de comportamiento. Como estudio de caso, examinamos dos programas hipotéticos de cambio de comportamiento, la jardinería silvestre y la contención de gatos, mediante la petición a expertos de considerar los comportamientos asociados con estos programas que directa o indirectamente afectan a la biodiversidad. Evaluamos los beneficios para el bandicut café (Isoodon obeselus) y el reyezuelo supremo (Malurus cyaeneus) mediante la obtención de estimaciones de expertos de la probabilidad de que cada especie persista en el paisaje con una gama establecida de escenarios de cambios de comportamiento en los cuales la aceptación de los comportamientos varió. Después comparamos estas estimaciones con un escenario de situación normal para determinar el beneficio relativo para la biodiversidad y la rentabilidad de cada escenario. Los expertos proyectaron que los programas de cambio de comportamiento beneficiarían a la biodiversidad y que los beneficios aumentarían con la creciente aceptación de los comportamientos deseados. También se pronosticó que los beneficios se acumularían mediante comportamientos indirectos, aunque los expertos estuvieron en desacuerdo sobre la magnitud del beneficio adicional proporcionado. Se estimó que los escenarios que combinaron los dos programas de cambio de comportamiento proporcionarían el mayor beneficio para las especies y serían los más rentables. Nuestro método podría usarse en otros contextos y potencialmente a diferentes escalas y fomenta el uso de herramientas de priorización para orientar a los programas de cambios en el comportamiento de conservación.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Conservação dos Recursos Naturais/métodos , Análise Custo-Benefício , Previsões , Incerteza
3.
Sci Rep ; 8(1): 4535, 2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29540746

RESUMO

While resistance to anticoagulant rodenticides is known to occur in many European populations of Norway rat and house mouse, to-date no data is available on the occurrence in Ireland of such resistance. No genetic evidence for the occurrence of resistance was found in 65 Norway rat samples analysed, indicative of an absence, or low prevalence, of resistance in rats in at least the Eastern region of the island of Ireland. The presence of two of the most commonly found amino acid substitutions Leu128Ser and Tyr139Cys associated with house mouse resistance to anticoagulant rodenticides was confirmed. The occurrence of two such mutations is indicative of the occurrence of resistance to anticoagulant rodenticides in house mice in the Eastern region of the island of Ireland.


Assuntos
Substituição de Aminoácidos , Resistência a Medicamentos , Proteínas de Membrana/genética , Rodenticidas , Vitamina K Epóxido Redutases/genética , Animais , Anticoagulantes/efeitos adversos , Irlanda , Camundongos , Ratos , Rodenticidas/efeitos adversos
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