Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Cancer Med ; 12(7): 8729-8741, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36647755

RESUMO

BACKGROUND: It is not well understood the overall changes that multidisciplinary teams (MDTs) have had to make in response to the COVID-19 pandemic, nor the impact that such changes, in addition to the other challenges faced by MDTs, have had on decision-making, communication, or participation in the context of MDT meetings specifically. METHODS: This was a mixed method, prospective cross-sectional survey study taking place in the United Kingdom between September 2020 and August 2021. RESULTS: The participants were 423 MDT members. Qualitative findings revealed hybrid working and possibility of virtual attendance as the change introduced because of COVID-19 that MDTs would like to maintain. However, IT-related issues, slower meetings, longer lists and delays were identified as common with improving of the IT infrastructure necessary going forward. In contrast, virtual meetings and increased attendance/availability of clinicians were highlighted as the positive outcomes resulting from the change. Quantitative findings showed significant improvement from before COVID-19 for MDT meeting organisation and logistics (M = 45, SD = 20) compared to the access (M = 50, SD = 12, t(390) = 5.028, p = 0.001), case discussions (M = 50, SD = 14, t(373) = -5.104, p = 0.001), and patient representation (M = 50, SD = 12, t(382) = -4.537, p = 0.001) at MDT meetings. DISCUSSION: Our study explored the perception of change since COVID-19 among cancer MDTs using mixed methods. While hybrid working was preferred, challenges exist. Significant improvements in the meeting organisation and logistics were reported. Although we found no significant perceived worsening across the four domains investigated, there was an indication in this direction for the case discussions warranting further 'live' assessments of MDT meetings.


Assuntos
COVID-19 , Neoplasias , Humanos , Estudos Prospectivos , Estudos Transversais , Pandemias , Equipe de Assistência ao Paciente , COVID-19/epidemiologia , Neoplasias/epidemiologia , Neoplasias/terapia
2.
Sci Total Environ ; 434: 3-12, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22245159

RESUMO

Eighteen months of 7-hourly analyses of rainfall and stream water chemistry are presented, spanning a wide range of chemical determinands and building on over 20 years of weekly records for the moorland headwaters of the river Severn. The high-frequency time series data show that hydrochemical responses to major hydrological and biological drivers of short-term variability in rainfall and rivers are not captured by conventional low-frequency monitoring programmes. A wealth of flow related, flow independent, diurnal, seasonal and annual fluctuations indicate a cacophony of interactions within the catchment and stream. The complexity of the chemical dynamics is visually obvious, although there appears to be no clear way of translating this complexity into a simple algorithm. The work provides a proof of concept for the complex structure of catchment functioning revealed by extensive high-frequency measurements coupled with high analytical sensitivity and reproducibility. It provides new insights into hydrogeochemical functioning and a novel resource for catchment modelling.


Assuntos
Chuva , Movimentos da Água , Qualidade da Água , Monitoramento Ambiental , Controle de Qualidade
3.
J Environ Monit ; 14(1): 34-40, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22009450

RESUMO

Al is a critical ecotoxicant in surface waters impacted by acidic deposition. Apart from the most acidic surface waters, Al concentrations are often considered to be controlled by Al(OH)(3) or aluminosilicate (clay) solubility for modelling studies. For many UK rivers there is no clear evidence for such solubility controls even though there is the potential under moderately acidic/alkaline conditions. Here, Al solubility in ground and river water is compared for acid sensitive catchments in mid-Wales. The results reveal that there may be a solubility control within the groundwater but a more complex state of affairs within the river. The groundwater is of high CO(2) content and once in the river it degasses to raise pH. However, there is limited change in Al concentration and hence the solubility relationship is lost. The results flag the potential importance of groundwater solubility controls for Al and the potential for the groundwater zone to act as an Al filter. For positive alkalinity groundwaters, the high CO(2) levels depress the pH to near the value for minimum Al solubility. However, there is no simple groundwater end-member. Examining Al solubility controls solely within the rivers provides cryptic and misleading clues to the hydrogeological controls for Al within catchments. Assessing the within-catchment processes requires direct measurement with full consideration of both inorganic and organic attenuation.


Assuntos
Alumínio/análise , Dióxido de Carbono/química , Água Subterrânea/química , Rios/química , Poluentes Químicos da Água/análise , Alumínio/química , Concentração de Íons de Hidrogênio , Solubilidade , País de Gales , Poluentes Químicos da Água/química
4.
Sci Total Environ ; 434: 186-200, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22119034

RESUMO

This paper examines two hydrochemical time-series derived from stream samples taken in the Upper Hafren catchment, Plynlimon, Wales. One time-series comprises data collected at 7-hour intervals over 22 months (Neal et al., 2012-this issue), while the other is based on weekly sampling over 20 years. A subset of determinands: aluminium, calcium, chloride, conductivity, dissolved organic carbon, iron, nitrate, pH, silicon and sulphate are examined within a framework of non-stationary time-series analysis to identify determinand trends, seasonality and short-term dynamics. The results demonstrate that both long-term and high-frequency monitoring provide valuable and unique insights into the hydrochemistry of a catchment. The long-term data allowed analysis of long-term trends, demonstrating continued increases in DOC concentrations accompanied by declining SO(4) concentrations within the stream, and provided new insights into the changing amplitude and phase of the seasonality of the determinands such as DOC and Al. Additionally, these data proved invaluable for placing the short-term variability demonstrated within the high-frequency data within context. The 7-hour data highlighted complex diurnal cycles for NO(3), Ca and Fe with cycles displaying changes in phase and amplitude on a seasonal basis. The high-frequency data also demonstrated the need to consider the impact that the time of sample collection can have on the summary statistics of the data and also that sampling during the hours of darkness provides additional hydrochemical information for determinands which exhibit pronounced diurnal variability. Moving forward, this research demonstrates the need for both long-term and high-frequency monitoring to facilitate a full and accurate understanding of catchment hydrochemical dynamics.


Assuntos
Estações do Ano , Qualidade da Água , País de Gales
5.
J Environ Monit ; 13(8): 2153-64, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21701704

RESUMO

Dissolved aluminium concentrations ([Al]) in the <0.45 µm filtered fraction are described for 54 UK river sites covering rural, acidic/acid sensitive, agricultural and urban typologies, and wide pH range (4 to 11). High [Al] occurred under acidic conditions and for acid runoff neutralised by bicarbonate rich groundwater. Thermodynamic analysis indicates Al hydroxide/hydroxy-silicate oversaturation at circumneutral pH across the rivers, but undersaturation at lower/higher pH. The oversaturation reflects in part the presence of Al bearing colloids as indicated by (1) [Al] being correlated with components associated with both lithogenic (Fe, Ti and lanthanides) colloids and organic carbon, (2) baseflow studies using cross-flow ultrafiltration and (3) comparison of our data with Acid Waters Monitoring Network (AWMN) information on labile and non-labile Al. Tree harvesting and emission reductions of SO(x) in acidic and acid sensitive catchments in mid-Wales led to acidification reversal, lower [Al] and changing [H(+)] - [Al] relationships. The [Al] decline was confined to acidic conditions while [Al] increased during the later part of the monitoring period with a peak around 2002 for moorland and forested systems. Colloidal production across the flow range was indicated late in the record by comparison of our data with information collected by the AWMN for a site in mid-Wales. This production seems interlinked with organic carbon and with dissolved CO(2) changes. In order for further understanding of Al hydrogeochemistry in river systems there is a need to integrate research that moves from equilibrium to kinetic and colloidal consideration including the critical issues of organic and inorganic controls within the context of bioavailability and aquatic stress. The colloidal Al may well be of low environmental concern to fish and other factors such as habitat may well be critical.


Assuntos
Alumínio/análise , Monitoramento Ambiental , Rios/química , Poluição Química da Água/análise , Carbono/análise , Coloides/química , Ecossistema , Monitoramento Ambiental/métodos , Cinética , Reino Unido
6.
Sci Total Environ ; 409(10): 1843-53, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21353288

RESUMO

Operationally defined dissolved Titanium [Ti] (the <0.45µm filtered fraction) in rivers draining rural, agricultural, urban and industrial land-use types in the UK averaged 2.1µg/l with a range in average of 0.55 to 6.48µg/l. The lowest averages occurred for the upland areas of mid-Wales the highest just downstream of major sewage treatment works (STWs). [Ti] in rainfall and cloud water in mid-Wales averaged 0.2 and 0.7µg/l, respectively. Average, baseflow and stormflow [Ti] were compared with two markers of sewage effluent and thus human population: soluble reactive phosphorus (SRP) and boron (B). While B reflects chemically conservative mixing, SRP declined downstream of STW inputs due to in-stream physico-chemical and biological uptake. The results are related to colloidal and sub-colloidal Ti inputs from urban/industrial conurbations coupled with diffuse background (geological) sources and within-river removal/retention under low flows as a result of processes of aggregation and sedimentation. The urban/industrial inputs increased background [Ti] by up to eleven fold, but the total anthropogenic Ti input might well have been underestimated owing to within-river retention. A baseline survey using cross-flow ultrafiltration revealed that up to 79% of the [Ti] was colloidal/nanoparticulate (>1kDa i.e. >c. 1-2nm) for the rural areas, but as low as 28% for the urban/industrial rivers. This raises fundamental issues of the pollutant inputs of Ti, with the possibility of significant complexation of Ti in the sewage effluents and subsequent breakdown within the rivers, as well as the physical dispersion of fine colloids down to the macro-molecular scale. Although not directly measured, the particulate Ti can make an important contribution to the net Ti flux.


Assuntos
Rios/química , Titânio/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Agricultura , Cidades , Monitoramento Ambiental , Resíduos Industriais/análise , População Rural , Ultrafiltração , Reino Unido
7.
Sci Total Environ ; 408(21): 5035-51, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20708776

RESUMO

This paper presents new information on the hydrology and water quality of the eroding peatland headwaters of the River Severn in mid-Wales and links it to the impact of plantation conifer forestry further down the catchment. The Upper Hafren is dominated by low-growing peatland vegetation, with an average annual precipitation of around 2650 mm with around 250 mm evaporation. With low catchment permeability, stream response to rainfall is "flashy" with the rising limb to peak stormflow typically under an hour. The water quality is characteristically "dilute"; stormflow is acidic and enriched in aluminium and iron from the acid organic soil inputs. Baseflow is circum-neutral and calcium and bicarbonate bearing due to the inputs of groundwater enriched from weathering of the underlying rocks. Annual cycling is observed for the nutrients reflecting uptake and decomposition processes linked to the vegetation and for arsenic implying seasonal water-logging within the peat soils and underlying glacial drift. Over the decadal scale, sulphate and nitrate concentrations have declined while Gran alkalinity, dissolved organic carbon and iron have increased, indicating a reduction in stream acidification. Within the forested areas the water quality is slightly more concentrated and acidic, transgressing the boundary for acid neutralisation capacity as a threshold for biological damage. Annual sulphate and aluminium concentrations are double those observed in the Upper Hafren, reflecting the influence of forestry and the greater ability of trees to scavenge pollutant inputs from gaseous and mist/cloud-water sources compared to short vegetation. Acidification is decreasing more rapidly in the forest compared to the eroding peatland possibly due to the progressive harvesting of the mature forest reducing the scavenging of acidifying inputs. For the Lower Hafren, long-term average annual precipitation is slightly lower, with lower average altitude, at around 2520mm and evaporation is around double that of the Upper Hafren.


Assuntos
Ácidos/análise , Monitoramento Ambiental , Rios/química , Poluentes Químicos da Água/análise , Alumínio/análise , Concentração de Íons de Hidrogênio , Árvores , Poluição da Água/prevenção & controle , Poluição da Água/estatística & dados numéricos
8.
Sci Total Environ ; 408(6): 1374-85, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19932654

RESUMO

The changing patterns of riverine boron concentration are examined for the Thames catchment in southern/southeastern England using data from 1997 to 2007. Boron concentrations are related to an independent marker for sewage effluent, sodium. The results show that boron concentrations in the main river channels have declined with time especially under baseflow conditions when sewage effluent dilution potential is at its lowest. While boron concentrations have reduced, especially under low-flow conditions, this does not fully translate to a corresponding reduction in boron flux and it seems that the "within-catchment" supplies of boron to the river are contaminated by urban sources. The estimated boron reduction in the effluent input to the river based on the changes in river chemistry is typically around 60% and this figure matches with an initial survey of more limited data for the industrial north of England. Data for effluent concentrations at eight sewage treatment works within the Kennet also indicate substantial reductions in boron concentrations: 80% reduction occurred between 2001 and 2008. For the more contaminated rivers there are issues of localised rather than catchment-wide sources and uncertainties over the extent and nature of water/boron stores. Atmospheric sources average around 32 to 61% for the cleaner and 4 to 14% for the more polluted parts. The substantial decreases in the boron concentrations correspond extremely well with the timing and extent of European wide trends for reductions in the industrial and domestic usage of boron-bearing compounds. It clearly indicates that such reductions have translated into lower average and peak concentrations of boron in the river although the full extent of these reductions has probably not yet occurred due to localised stores that are still to deplete.


Assuntos
Boro/análise , Detergentes/química , Rios/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Estações do Ano , Esgotos/química , Sódio/análise , Reino Unido , Poluição Química da Água/estatística & dados numéricos , Abastecimento de Água/análise
9.
Environ Pollut ; 153(2): 273-83, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17950507

RESUMO

Concentrations of seven metals were measured in over 1000 samples as part of an integrated survey. Sixteen metal pairs were significantly positively correlated. Cluster analysis identified two clusters. Metals from the largest (Cr, Cu, Ni, V, Zn), but not the smallest (Cd, Pb) cluster were significantly negatively correlated with spatial location and soil pH and organic matter content. Cd and Pb were not correlated with these parameters, due possibly to the masking effect of recent extensive release. Analysis of trends with soil properties in different habitats indicated that general trends may not necessarily be applicable to all areas. A risk assessment indicated that Zn poses the most widespread direct risk to soil fauna and Cd the least. Any risks associated with high metal concentrations are, however, likely to be greatest in habitats such as arable and horticultural, improved grassland and built up areas where soil metal concentrations are more frequently elevated.


Assuntos
Metais/análise , Microbiologia do Solo , Poluentes do Solo/análise , Solo/análise , Agricultura , Cádmio/análise , Cromo/análise , Cobre/análise , Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental , Geografia , Substâncias Húmicas/análise , Concentração de Íons de Hidrogênio , Resíduos Industriais , Chumbo/análise , Níquel/análise , Medição de Risco/métodos , Espectrofotometria Atômica , Reino Unido , Zinco/análise
10.
Sci Total Environ ; 314-316: 99-120, 2003 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-14499529

RESUMO

Soluble reactive phosphorus (SRP) data are presented for rainfall, cloud water, soil waters, stream waters and groundwaters at the Plynlimon catchments in mid Wales to examine the hydrochemical functioning of inorganic phosphorus for an acidic and acid sensitive area characteristic of much of the UK uplands. In general, stream water concentrations are low compared to lowland areas. Average concentrations of SRP in rainfall and cloud water (0.3 and 0.9 microM l(-1), respectively) are higher than in stream water with wider ranges in concentration (0-19.3 and 0-20.9 microM l(-1), respectively). Throughfall and stemflow is enriched in SRP compared to rain and cloud water by a factor of approximately twofold and sixfold, respectively: the average concentrations and ranges are 0.73 and 0-6.61 microM l(-1) for throughfall and 2.12 and 0-18.61 microM l(-1) for stemflow. Soil water SRP concentrations measured in the surface layers of representative areas of podzol and gley soils, are further enriched with respect to inputs. Average concentrations and ranges for the L/F and Oh horizons in the podzols are 3.1 microM l(-1) (range: 0.03-17.2 microM l(-1)) and 0.75 microM l(-1) (range: 0.03-2.64 microM l(-1)), respectively. Correspondingly, the average values and ranges for the L/F and Oh horizons in the gley are 2 microM l(-1) (range: 0.03-16.65 microM l(-1)) and 0.4 microM l(-1) (range: 0.03-8.61 microM l(-1)). SRP concentrations in stream and ground water are lower than in atmospheric inputs and surface soil waters and show marked spatial variability. This variability is linked to three catchment features. (1) For streams draining podzolic soils, most of the SRP is retained by the catchment. For this situation, stream and ground waters have average concentrations of approximately 0.05 microM l(-1) with a range of 0-1.47 microM l(-1). There is no clear stream or groundwater SRP response to felling despite a large release of SRP from felling debris (brash) and the forest floor (L/F horizon) with average post-felling concentrations of 11.02 microM l(-1) (0.40-155.0 microM l(-1)) and 23.60 microM l(-1) (0.26-172.23 microM l(-1)), respectively. (2) For forested catchments with gley soils, stream water SRP concentrations are more variable with, in one case, much higher concentrations than for the podzol counterparts (range in average 0.05-0.46 microM l(-1)). (3) For the streams draining gley soils, felling results in a mixed SRP response. At the local scale (ditch drainage), there is a marked enrichment in SRP concentration (average concentrations increase from 0.05 to 1.31 microM l(-1), with a peak concentration of 4.0 microM l(-1)). This response is consistent with the observed mobilisation of SRP from brash and forest floor material (post-felling mean concentrations of 9.39 and 11.94 microM l(-1), respectively). However, stream water concentrations are an order of magnitude lower than observed in the soil waters implying considerable immobilisation of SRP between the soils and the stream. At the larger catchment scale, no discernable enrichment in SRP is observed following felling. The results are related to input-output budgets and the findings interpreted in terms of the dominant hydrogeochemical processes operative and environmental management issues.


Assuntos
Fósforo/análise , Chuva , Solo , Água/química , Monitoramento Ambiental , Agricultura Florestal , Fenômenos Geológicos , Geologia , Fósforo/química , Folhas de Planta , Valores de Referência , Solubilidade , Árvores , País de Gales , Abastecimento de Água
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA