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1.
Environ Evid ; 12(1): 12, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-39294822

RESUMO

BACKGROUND: This systematic map principally sought to understand the different forms of effectiveness that existing studies evaluate in relation to Natural Flood Management (NFM) in the UK with a supplementary question of whether studies engaged with climate change and future flood risk. NFM measures seek to protect, enhance, emulate, or restore the natural function of rivers as part of approaches to flood risk management (FRM). While there is agreement in both academic and practice/policy literature that NFM should be part of a holistic FRM strategy to address current and future flood risk, the specifics of how to expand the application of and consistently implement NFM successfully in practice are less well known. A core focus of this study is on how the effectiveness of NFM measures is evaluated in different studies based on approaches drawn from the Environmental Impact Assessment (EIA) literature: procedural, substantive, transactive and normative. The systematic map also examines how studies account for climate change, which is a crucial issue given the connections between NFM and climate change adaptation and resilience. METHODS: We searched 13 bibliographic databases, Google scholar as a web-based search engine, and 21 organisational sites. Articles were screened by title, abstract, and full text based on defined eligibility criteria. Checks were performed for consistency amongst reviewers. Forms of effectiveness were coded on the basis of the included studies in the systematic map. The quantity and characteristics of the available evidence are summarised with the frequencies of effectiveness forms for each NFM measure are presented in heat maps. REVIEW FINDINGS: A total of 216 articles reported eligible studies that were coded as part of the systematic map. Overall, the systematic map shows that the majority of studies considered at least one approach to effectiveness; however, very few studies considered multiple forms of effectiveness. The systematic map also demonstrates that climate change is considered systematically by around one-quarter of studies although many studies make claims about NFM's effectiveness in the face of future climatic change. CONCLUSIONS: NFM can be effective in several different ways owing to their multiple benefits; however, there are evidence gaps around understanding these different forms of effectiveness. This is particularly marked for studies considering transactive and normative effectiveness. Interdisciplinary studies are more likely to consider multiple forms of effectiveness. This systematic map also found that whilst 75% of studies mention future climate change in their studies, only 24.1% contain a systematic consideration of the issue through, for example, using climate change projections. NFM is also at risk of climate change (e.g. through drought) and therefore it is imperative that study designs seek to incorporate consideration of effectiveness under future climate change. Policymakers should be made aware of the lack of understanding of how NFM measures perform under future climate change.

2.
Environ Toxicol Chem ; 39(10): 2076-2089, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32681761

RESUMO

Fish acute toxicity tests are conducted as part of regulatory hazard identification and risk-assessment packages for industrial chemicals and plant protection products. The aim of these tests is to determine the concentration which would be lethal to 50% of the animals treated. These tests are therefore associated with suffering in the test animals, and Organisation for Economic Co-operation and Development test guideline 203 (fish, acute toxicity) studies are the most widely conducted regulatory vertebrate ecotoxicology tests for prospective chemical safety assessment. There is great scope to apply the 3Rs principles-the reduction, refinement, and replacement of animals-in this area of testing. An expert ecotoxicology working group, led by the UK National Centre for the Replacement, Refinement and Reduction of Animals in Research, including members from government, academia, and industry, reviewed global fish acute test data requirements for the major chemical sectors. The present study highlights ongoing initiatives and provides an overview of the key challenges and opportunities associated with replacing, reducing, and/or refining fish acute toxicity studies-without compromising environmental protection. Environ Toxicol Chem 2020;39:2076-2089. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Alternativas aos Testes com Animais/métodos , Ecotoxicologia/métodos , Peixes , Substâncias Perigosas/toxicidade , Testes de Toxicidade Aguda/métodos , Alternativas aos Testes com Animais/legislação & jurisprudência , Animais , Ecotoxicologia/legislação & jurisprudência , Dose Letal Mediana , Organização para a Cooperação e Desenvolvimento Econômico , Medição de Risco , Testes de Toxicidade Aguda/normas
3.
Sci Adv ; 4(9): eaat5528, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30191179

RESUMO

Global warming, acidification, and oxygen stress at the Paleocene-Eocene Thermal Maximum (PETM) are associated with severe extinction in the deep sea and major biogeographic and ecologic changes in planktonic and terrestrial ecosystems, yet impacts on shallow marine macrofaunas are obscured by the incompleteness of shelf sections. We analyze mollusk assemblages bracketing (but not including) the PETM and find few notable lasting impacts on diversity, turnover, functional ecology, body size, or life history of important clades. Infaunal and chemosymbiotic taxa become more common, and body size and abundance drop in one clade, consistent with hypoxia-driven selection, but within-clade changes are not generalizable across taxa. While an unrecorded transient response is still possible, the long-term evolutionary impact is minimal. Adaptation to already-warm conditions and slow release of CO2 relative to the time scale of ocean mixing likely buffered the impact of PETM climate change on shelf faunas.


Assuntos
Evolução Biológica , Fósseis , Moluscos/anatomia & histologia , Moluscos/fisiologia , Animais , Organismos Aquáticos , Biodiversidade , Tamanho Corporal , Fósseis/anatomia & histologia , Aquecimento Global , Moluscos/classificação
4.
Proc Biol Sci ; 285(1879)2018 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-29848656

RESUMO

River systems worldwide have been modified for human use and the downstream ecological consequences are often poorly understood. In the Colorado River estuary, where upstream water diversions have limited freshwater input during the last century, mollusc remains from the last several hundred years suggest widespread ecological change. The once abundant clam Mulinia modesta has undergone population declines of approximately 94% and populations of predators relying on this species as a food source have probably declined, switched to alternative prey species or both. We distinguish between the first two hypotheses using a null model of predation preference to test whether M. modesta was preyed upon selectively by the naticid snail, Neverita reclusiana, along the estuary's past salinity gradient. To evaluate the third hypothesis, we estimate available prey biomass today and in the past, assuming prey were a limiting resource. Data on the frequency of drill holes-identifiable traces of naticid predation on prey shells-showed several species, including M. modesta, were preferred prey. Neverita reclusiana was probably able to switch prey. Available prey biomass also declined, suggesting the N. reclusiana population probably also declined. These results indicate a substantial change to the structure of the benthic food web. Given the global scale of water management, such changes have probably also occurred in many of the world's estuaries.


Assuntos
Bivalves/fisiologia , Cadeia Alimentar , Caramujos/fisiologia , Movimentos da Água , Animais , Estuários , México , Comportamento Predatório
5.
Front Microbiol ; 9: 345, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29552001

RESUMO

Commercial poultry abattoirs were evaluated to determine the efficacy of the multi-hurdle antimicrobial strategy employed to reduce the microbial load present on incoming broilers from the farm. As next generation sequencing (NGS) has been recently employed to characterize the poultry production system, this study utilized 16S High throughput sequencing (HTS) and quantitative plating data to profile the microbiota of chicken carcasses and determine the efficacy of the multi-hurdle antimicrobial system. Aerobic plate count (APC) and Enterobacteriaceae (EB) microbial counts were quantified from whole bird carcass rinsates (WBCR). The remaining rinsates underwent microbiome analysis using 16S rRNA gene fragments on an Illumina MiSeq and were analyzed by Quantitative Insights into Microbial Ecology (QIIME). The key stages of processing were determined to be at rehang, pre-chill, and post-chill as per the Salmonella Reduction Regulation (75 Fed. Reg. 27288-27294). The APC microbial data from rehang, pre-chill, and post-chill were mean log 4.63 CFU/mL, 3.21 CFU/mL, and 0.89 CFU/mL and EB counts were mean log 2.99 CFU/mL, 1.95 CFU/mL, and 0.35 CFU/mL. NGS of WBCR identified 222 Operational Taxonomic Units' (OTU's) of which only 23 OTU's or 10% of the population was recovered post-chill. Microbiome data suggested a high relative abundance of Pseudomonas at post-chill. Additionally, Pseudomonas, Enterobacteriaceae, and Weeksellaceae Chryseobacterium have been identified as potential indicator organisms having been isolated from all processing abattoirs and sampling locations. This study provides insight into the microbiota of commercial broilers during poultry processing.

7.
PLoS One ; 8(5): e63071, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23690981

RESUMO

The fossil record is the only source of information on the long-term dynamics of species assemblages. Here we assess the degree of ecological stability of the epifaunal pterioid bivalve assemblage (EPBA), which is part of the Middle Devonian Hamilton fauna of New York--the type example of the pattern of coordinated stasis, in which long intervals of faunal persistence are terminated by turnover events induced by environmental change. Previous studies have used changes in abundance structure within specific biofacies as evidence for a lack of ecological stability of the Hamilton fauna. By comparing data on relative abundance, body size, and predation, indexed as the frequency of unsuccessful shell-crushing attacks, of the EPBA, we show that abundance structure varied through time, but body-size structure and predation pressure remained relatively stable. We suggest that the energetic set-up of the Hamilton fauna's food web was able to accommodate changes in species attributes, such as fluctuating prey abundances. Ecological redundancy in prey resources, adaptive foraging of shell-crushing predators (arising from predator behavioral or adaptive switching in prey selection in response to changing prey abundances), and allometric scaling of predator-prey interactions are discussed as potential stabilizing factors contributing to the persistence of the Hamilton fauna's EPBA. Our study underscores the value and importance of multiple lines of evidence in tests of ecological stability in the fossil record.


Assuntos
Ecologia , Fósseis , Animais , Biodiversidade , Tamanho Corporal , Cadeia Alimentar , Comportamento Predatório
8.
J Food Sci ; 75(8): M515-20, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21535507

RESUMO

Post chill whole poultry carcasses from a commercial processing plant were stored in a processing combo at room temperature (70 °F/21 °C) for 54 h to mimic the scenario of temperature abuse before further processing. Temperature data were collected in 1-min intervals and averaged each hour by 9 temperature data loggers. Two linear regressions were developed for the combo and internal breast temperature and slopes were nearly identical. Microbial data was collected by performing whole bird carcass rinses that were enumerated for aerobic plate count (APC), Enterobacteriaceae, Escherichia coli, and total coliform. Samples were collected from the chiller chute at time zero for initial bacterial counts. Carcass sampling continued once the internal breast temperature achieved 45 °F (7 °C 10 h) and continued every 2 h until the final internal breast temperature was 63 °F (17 °C 54 h). Linear regressions were developed for the first 26 h, which exhibited no statistically significant growth except for Enterobacteriaceae. A 2nd linear regression (28 to 54 h) exhibited significant growth for all analyses. Overall, APC increased from a log(10) colony forming unit (CFU)/mL count of 2.86 to 7.02, Enterobacteriaceae increased from 0.66 to 6.64, coliform increased from 0.72 to 4.81, and E. coli increased from 0.53 to 4.45. Denaturing gradient gel electrophoresis was performed to detect changes in the bacterial populations, which indicated 95% similarity within sampled groups, but the overall percent similarity among samples collected over 54 h was 8%. From the data, microbial growth demonstrates a period of 26 h for minimal growth; therefore, the product could be further processed rather than designated as waste.


Assuntos
Enterobacteriaceae/crescimento & desenvolvimento , Manipulação de Alimentos , Bactérias Aeróbias Gram-Negativas/crescimento & desenvolvimento , Carne/análise , Carne/microbiologia , Temperatura , Animais , Galinhas , Contagem de Colônia Microbiana , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/isolamento & purificação , Bactérias Aeróbias Gram-Negativas/genética , Bactérias Aeróbias Gram-Negativas/isolamento & purificação , Cinética , Tipagem Molecular , Filogenia
9.
Part Fibre Toxicol ; 4: 12, 2007 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-18053256

RESUMO

Nanotechnology is the new industrial revolution of the 21st Century as the various processes lead to radical improvements in medicine, manufacturing, energy production, land remediation, information technology and many other everyday products and applications. With this revolution however, there are undoubted concerns for health, safety and the environment which arise from the unique nature of materials and processes at the nanometre scale.The in vitro assays used in the screening strategy are all validated, internationally accepted protocols and provide a useful indication of potential toxicity of a chemical as a result of effects on various toxicological endpoints such as local site of contact (dermal) irritation, general cytotoxicity and mutagenicity.The initial in vitro screening strategy described in this paper to investigate the potential health implications, if any, which may arise following exposure to one specific application of nanoparticulate cerium oxide used as a diesel fuel borne catalyst, reflects a precautionary approach and the results will inform judgement on how best to proceed to ensure safe use.

10.
IEEE Trans Image Process ; 14(8): 1088-95, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16121457

RESUMO

Computational mathematical morphology (CMM) is a nonlinear filter representation particularly amenable to real-time image processing. A windowed, translation-invariant filter is represented by a set of less-than-or-equal decisions that are executed by a parallel arrangement of comparators. In the state-of-the-art implementation, each pixel value of a windowed observation is indexed into separate lookup tables to retrieve a set of bit vectors which are "anded" together to produce a bit vector with a unique nonzero bit. The position of that bit is used to look up a filter value in a table. The number of stored bit vectors is proportional to the number of image gray levels. An architecture for CMM is presented that uses a minimal number of bit vectors so that required memory is less sensitive to the number of gray levels. The number of pixels in the observation window is the dimension of the image space. In the proposed architecure, basis elements are projected to subspaces of the image space and only bit vectors unique to each subspace are stored. Each projection corresponds to a subspace partition. Filter memory is greatly reduced by using intermediate lookup tables to map observations to unique bit vectors. We investigate two possible projection strategies: A fixed, singleton architecture, in which each subspace is one dimension, and a minimal architecture, in which a large number of subspace projections are searched for, one with minimal memory. Insensitivity to the number of gray levels is demonstrated through simulated, random-image space tessellations. We also present memory savings in a digital photocopier application.


Assuntos
Algoritmos , Gráficos por Computador , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Armazenamento e Recuperação da Informação/métodos , Reconhecimento Automatizado de Padrão/métodos , Processamento de Sinais Assistido por Computador , Metodologias Computacionais , Análise Numérica Assistida por Computador
11.
IEEE Trans Image Process ; 12(2): 153-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-18237896

RESUMO

A real-time, compact architecture is presented for translation-invariant windowed nonlinear discrete operators represented in computational mathematical morphology. The architecture enables output values to be computed in a fixed number of operations and thus can be pipelined. Memory requirements for an operator are proportional to its basis size. An operator is implemented by three steps: 1) each component of a vector observation is used as an index into a table of bit vectors; 2) all retrieved bit vectors are "ANDed" together; and 3) the position of the first nonzero bit is used as an index to a table of output values. Computational mathematical morphology is described, the new architecture is illustrated through examples, and formal proofs are given. A modification of the basic architecture provides for increasing operators.

12.
Postgrad Med ; 57(6): 25, 1975 May.
Artigo em Inglês | MEDLINE | ID: mdl-27414198
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