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1.
Mar Pollut Bull ; 199: 115917, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38118398

RESUMO

Addressing the wide range of marine pollution problems facing the global ocean requires a continual transfer of credible, relevant and timely scientific information to policy and decision makers in coastal and ocean management. The United Nations GESAMP (Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection) is a long-standing scientific advisory group providing such information on a wide range of marine topics and emerging issues of concern to ten UN Sponsoring Organizations. This paper presents an overview of GESAMPs operation and examples of its current work. The group's scientific output is often cited by national governments, inter-governmental groups, and a range of non-governmental groups. Given the growing concerns about ocean health and the impacts of many stressors in an era of climate change, the development of timely and effective ocean policy and decision making would benefit from wider recognition and application of GESAMPs work.


Assuntos
Conservação dos Recursos Naturais , Poluição Ambiental , Políticas , Oceanos e Mares
2.
Sci Total Environ ; 409(23): 5020-5, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21911246

RESUMO

A depth profile of (239)Pu and (240)Pu specific activities and isotope ratios was determined in an inter-tidal sediment core from the Esk Estuary in the northeastern Irish Sea. The study site has been impacted with plutonium through routine radionuclide discharges from the Sellafield nuclear reprocessing plant in Cumbria, NW England. A pronounced sub-surface maximum of ~10 k Bq kg(-1) was observed for (239+240)Pu, corresponding to the peak in Pu discharge from Sellafield in 1973, with a decreasing trend with depth down to ~0.04 k Bq kg(-1) in the deeper layers. The depth profile of (239+240)Pu specific activities together with results from gamma-ray spectrometry for (137)Cs and (241)Am was compared with reported releases from the Sellafield plant in order to estimate a reliable sediment chronology. The upper layers (1992 onwards) showed higher (239+240)Pu specific activities than would be expected from the direct input of annual Sellafield discharges, indicating that the main input of Pu is from the time-integrated contaminated mud patch of the northeastern Irish Sea. The (240)Pu/(239)Pu atom ratios ranged from ~0.03 in the deepest layers to >0.20 in the sub-surface layers with an activity-weighted average of 0.181. The decreasing (240)Pu/(239)Pu atom ratio with depth reflects the changing nature of operations at the Sellafield plant from weapons-grade Pu production to reprocessing spent nuclear fuel with higher burn-up times in the late 1950s. In addition, recent annual (240)Pu/(239)Pu atom ratios in winkles collected during 2003-2008 from three stations along the Cumbrian coastline showed no significant spatial or temporal differences with an overall average of 0.204, which supports the hypothesis of diluted Pu input from the contaminated mud patch.


Assuntos
Monitoramento Ambiental/estatística & dados numéricos , Poluentes Ambientais/análise , Sedimentos Geológicos/química , Plutônio/análise , Amerício/análise , Oceano Atlântico , Césio/análise , Monitoramento Ambiental/métodos , Irlanda , Centrais Nucleares , Radioisótopos/análise , Espectrometria gama , Fatores de Tempo
3.
J Environ Radioact ; 96(1-3): 63-74, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17512643

RESUMO

This paper presents new data on the distribution of long-lived radionuclides in Irish Sea subtidal sediments, contaminated as a result of the BNFL Sellafield discharges. The results from different sampling campaigns in 1999 have been combined to assess the extent of radionuclide mobility relative to earlier surveys, in both the eastern and western Irish Sea areas, and to investigate changes in radionuclide distribution over time. The results appear to confirm the trend of continuing re-distribution and transfer of contamination away from the English coast. West of the Isle of Man, radionuclide concentrations and inventories have remained more or less constant. The inventory of radionuclides in sandy sediments in the eastern Irish Sea is still under-represented by current sampling, but could be improved by deeper and more extensive vibrocoring.


Assuntos
Monitoramento de Radiação/métodos , Radioisótopos/análise , Movimentos da Água , Poluentes Radioativos da Água/análise , Amerício/análise , Radioisótopos de Césio/análise , Sedimentos Geológicos , Irlanda , Oceanos e Mares , Plutônio/análise , Poluentes Radioativos , Resíduos Radioativos , Reino Unido , Água , Contaminação Radioativa da Água
4.
CNS Spectr ; 10(6): 481-8, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15908902

RESUMO

Alzheimer's disease is a progressive condition characterized by a loss of cognition, altered behavior, and a loss of functional ability, such as bathing, dressing, toileting, and organizing finances. Family and friends provide nearly three quarters of all care for patients with Alzheimer's disease. This informal care results in significant burden to caregivers. Caregiver burden is the set of physical, psychological or emotional, social, and financial problems that family members may experience when caring for impaired older adults. Caregivers of Alzheimer's disease patients report higher rates of physical symptoms, mortality, depression, and fatigue, as well as adverse effects on employment compared with those who are not caregivers for Alzheimer's disease patients. In many cases, the same family members are responsible for both out-of-pocket expenditures and caregiving duties. For this article, a MEDLINE search using the key words "caregiver and Alzheimer's disease" and "cost and Alzheimer's disease" was performed. The purpose of this article is to review the literature on caregiver burden, the components of caregiver burden, effects of caregiving on the health of caregivers, the cost of Alzheimer's disease on the caregiver and society, and the benefits attainable with treatment.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Cuidadores/psicologia , Cuidadores/estatística & dados numéricos , Inibidores da Colinesterase/uso terapêutico , Efeitos Psicossociais da Doença , Depressão/prevenção & controle , Depressão/psicologia , Emprego/estatística & dados numéricos , Galantamina/uso terapêutico , Transtornos do Sono-Vigília/epidemiologia , Idoso , Humanos
5.
J Environ Radioact ; 77(2): 159-73, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15312701

RESUMO

In 1994 there were substantial increases in the quantity of 99Tc discharged into the north-east Irish Sea from BNFL Sellafield (UK), concomitant with improvements in waste treatment procedures. As a consequence, the concentration of 99Tc observed in seawater and biota samples, taken from the Irish Sea coastline, increased significantly. Elevated concentrations were also reported in Dutch, Danish, Norwegian, Swedish and Arctic waters in subsequent years. In the present study a simple numerical model was developed and applied to time-series data of 99Tc concentrations in the brown seaweed Fucus vesiculosus, collected from three UK sites in the vicinity of Sellafield (St. Bees, Heysham, Port William). The model considered site-specific scaling effects, lag times, previous discharge history and potential seasonal variation in uptake. In general, there was a good fit between predicted and observed concentrations, but the degree of uncertainty varied inversely with the frequency of sampling. We did not observe a significant seasonal variation. The modelled lag times to the three sites were consistent with transport times based on observations of the water column distribution of 99Tc. The model was applied to a variety of discharge scenarios, reflecting current discussion on the future management of 99Tc releases. Concentrations in Fucus reached asymptotic values in 3-10 years, depending on the scenario and sampling site under consideration.


Assuntos
Fucus/química , Tecnécio/análise , Poluentes Radioativos da Água/análise , Monitoramento Ambiental , Modelos Teóricos , Reatores Nucleares , Oceanos e Mares , Reprodutibilidade dos Testes , Fatores de Tempo , Reino Unido
6.
J Environ Radioact ; 74(1-3): 185-98, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15063547

RESUMO

The radionuclide (99)Tc had been discharged from the nuclear reprocessing facility in Sellafield (UK) into the Irish Sea in increased amounts in the 1990s. We compare the simulated dispersion of (99)Tc in surface water as calculated by a hydrodynamic model and an assessment box model with field-observations from 1996 to 1999 to study concentrations, pathways and travel times. The model results are consistent with the observations and show the typical pathway of dissolved radionuclides from the Irish Sea via the North Sea along the Norwegian Coast. Subsequently the contaminated water separates into three branches of which the two Arctic branches bear the potential for future monitoring of the signal in the next decades. The results of the hydrodynamic model indicate a large variability of surface concentrations in the West Spitsbergen Current which has implications for future monitoring strategies. According to the observed and simulated distributions we suggest an improved box model structure to better capture the pattern for concentrations at the surface.


Assuntos
Modelos Teóricos , Tecnécio/análise , Poluentes Radioativos da Água/análise , Regiões Árticas , Monitoramento Ambiental , Centrais Elétricas , Movimentos da Água
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