982 resultados para Routine


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The Continuous Plankton Recorder has been sampling the northeast Pacific on a routine basis since 2000. Although this is a relatively short time series still, climate variability within that time has caused noticeable related changes in the plankton. The earlier part of the time series followed the 1999 La Nina and conditions were cool, but conditions between 2003 and 2005 were anomalously warm. Oceanic zooplankton have responded to this warming in several ways that are discernible in CPR data. The seasonal cycle of mesozooplankton biomass in the eastern Gulf of Alaska has shifted earlier in the spring by a few weeks (sampling resolution is too coarse to be more accurate). The copepod Neocalanus plumchruslflemingeri is largely responsible as it makes up a high proportion of the spring surface biomass and stage-based determinations have shown an earlier maximum in warmer years across much of the northeast Pacific, spanning nearly 20 degrees of latitude. Summer copepod populations are more diverse than in spring, although lower in biomass. The northwards extension of southern taxa in the summer correlates with surface temperature and in warmer years southern taxa are found further north than in cooler years. These findings support the importance of monitoring the open ocean particularly as it is an important foraging ground for large fish, birds and mammals. Higher trophic levels may time their reproduction or migration to coincide with the abundance of particular prey which may be of a different composition and/or lower abundance at a particular time in warmer conditions.

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First designed in the 1920s and in routine use in the Atlantic since the 1930s, the Continuous Plankton Recorder (CPR) is an ocean observing tool that has been used in the north Pacific since 2000 and still retains its relevance. It was the sampler of choice in 2000 because it is reliable, cost-effective, samples on the scale of an entire ocean and, while not a perfect sampler, its limitations are mostly well-known. Earlier this year, the GOOS Scientific Steering Committee endorsed the north Pacific CPR survey as an ocean observing tool. Data from the seven years of sampling in the North Pacific have already shown responses in open ocean plankton to changes from cool to warm ocean conditions, from which we can start to make predictions on responses to future climate changes. This presentation describes and presents results from the survey, and ends with some thoughts on development of the north Pacific CPR survey.

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The Continuous Plankton Recorder (CPR) began its first routine deployment to collect plankton samples in the North Sea in 1931. The better part of a century after that event, the Recorder is used for sampling plankton widely in many oceans. The CPR is designed to be towed behind ships of opportunity (such as commercial and passenger vessels) and to collect plankton samples along the ship’s path. The samples provide information on the broad scale spatial distributions of larger hard-shelled phytoplankton and robust mesozooplankton organisms (Richardson et al., 2006). Changes in these distributions provide indices for the biological health of the ocean including those required for fisheries and for assessment of climate change impacts.

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Knowledge on the impact of climate variability in the diet of planktivorous fish is limited by the laborious work involved in stomach content analysis, impractical for large scale studies. Routine measurements of plankton such as the Continuous Plankton Recorder (CPR) survey provide valuable information of the temporal variation of phyto- and zooplankton prey availability for higher trophic levels. Sardines are a world-wide distributed and commercially important planktivorous fish, at the basis of the pelagic marine food web. Being predominantly non-selective filter-feeders, their diets closely correspond to the water plankton species and a significant relationship was recently found between Sardina pilchardus feeding intensity and remotely sensed chlorophyll alpha . Data of sardine stomach prey composition and CPR were obtained during 2003 for the same location off the west coast of Portugal, an area characterised by strong seasonality of plankton abundance and composition, mainly governed by upwelling events. Phyto- and zooplankton prey in sardine stomachs were identified to the lowest possible taxa and their numerical and volumetric abundance was registered, as well as their contribution to the prey carbon content. The seasonal variation of the abundance and composition of sardine diet was then compared to the abundance and composition of the water plankton obtained with the CPR at the same time and for the same area where the fish were collected, in order to evaluate if CPR data can be used to proxy sardine prey availability and diet composition at large temporal scales.

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The relationship between toxic marine microalgae species and climate change has become a high profile and well discussed topic in recent years, with research focusing on the possible future impacts of changing hydrological conditions on Harmful Algal Bloom (HAB) species around the world. However, there is very little literature concerning the epidemiology of these species on marine organisms and human health. Here, we examine the current state of toxic microalgae species around the UK, in two ways: first we describe the key toxic syndromes and gather together the disparate reported data on their epidemiology from UK records and monitoring procedures. Secondly, using NHS hospital admissions and GP records from Wales, we attempt to quantify the incidence of shellfish poisoning from an independent source. We show that within the UK, outbreaks of shellfish poisoning are rare but occurring on a yearly basis in different regions and affecting a diverse range of molluscan shellfish and other marine organisms. We also show that the abundance of a species does not necessarily correlate to the rate of toxic events. Based on routine hospital records, the numbers of shellfish poisonings in the UK are very low, but the identification of the toxin involved, or even a confirmation of a poisoning event is extremely difficult to diagnose. An effective shellfish monitoring system, which shuts down aquaculture sites when toxins exceed regularity limits, has clearly prevented serious impact to human health, and remains the only viable means of monitoring the potential threat to human health. However, the closure of these sites has an adverse economic impact, and the monitoring system does not include all toxic plankton. The possible geographic spreading of toxic microalgae species is therefore a concern, as warmer waters in the Atlantic could suit several species with southern biogeographical affinities enabling them to occupy the coastal regions of the UK, but which are not yet monitored or considered to be detrimental.

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The Continuous Plankton Recorder (CPR) survey has been sampling plankton in the North Sea since 1931. However the identification of the larval and juvenile fish taken in the survey has not been a part of the routine analysis of the samples. Specialist analysis of the fish was carried out between 1948 and the early 1980s but the data were available as hard copy only. As part of MarBEF, data on >60 taxa from 1948 to 1972 have been entered on a database which is now linked to EUROBIS to show the biogeographical information and the data are available for general research. Examples of the data are shown. These data provide a background on the variability of fish stocks before the recent period of rapid warming and in some cases before significant fisheries developed. Data for subsequent years will be made available as possible and work is now underway to bring the analysis up to date. This will provide time series over six decades.

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An extensive literature base worldwide demonstrates how spatial differences in estuarine fish assemblages are related to those in the environment at (bio)regional, estuary-wide or local (within-estuary) scales. Few studies, however, have examined all three scales, and those including more than one have often focused at the level of individual environmental variables rather than scales as a whole. This study has identified those spatial scales of environmental differences, across regional, estuary-wide and local levels, that are most important in structuring ichthyofaunal composition throughout south-western Australian estuaries. It is the first to adopt this approach for temperate microtidal waters. To achieve this, we have employed a novel approach to the BIOENV routine in PRIMER v6 and a modified global BEST test in an alpha version of PRIMER v7. A combination of all three scales best matched the pattern of ichthyofaunal differences across the study area (rho = 0.59; P = 0.001), with estuary-wide and regional scales accounting for about twice the variability of local scales. A shade plot analysis showed these broader-scale ichthyofaunal differences were driven by a greater diversity of marine and estuarine species in the permanently-open west coast estuaries and higher numbers of several small estuarine species in the periodically-open south coast estuaries. When interaction effects were explored, strong but contrasting influences of local environmental scales were revealed within each region and estuary type. A quantitative decision tree for predicting the fish fauna at any nearshore estuarine site in south-western Australia has also been produced. The estuarine management implications of the above findings are highlighted.

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Transient micronutrient enrichment of the surface ocean can enhance phytoplankton growth rates and alter microbial community structure with an ensuing spectrum of biogeochemical feedbacks. Strong phytoplankton responses to micronutrients supplied by volcanic ash have been reported recently. Here we: (i) synthesize findings from these recent studies; (ii) report the results of a new remote sensing study of ash fertilization; and (iii) calculate theoretical bounds of ash-fertilized carbon export. Our synthesis highlights that phytoplankton responses to ash do not always simply mimic that of iron amendment; the exact mechanisms for this are likely biogeochemically important but are not yet well understood. Inherent optical properties of ash-loaded seawater suggest rhyolitic ash biases routine satellite chlorophyll-a estimation upwards by more than an order of magnitude for waters with <0.1 mg chlorophyll-a m-3, and less than a factor of 2 for systems with >0.5 mg chlorophyll-a m-3. For this reason post-ash-deposition chlorophyll-a changes in oligotrophic waters detected via standard Case 1 (open ocean) algorithms should be interpreted with caution. Remote sensing analysis of historic events with a bias less than a factor of 2 provided limited stand-alone evidence for ash-fertilization. Confounding factors were poor coverage, incoherent ash dispersal, and ambiguity ascribing biomass changes to ash supply over other potential drivers. Using current estimates of iron release and carbon export efficiencies, uncertainty bounds of ash-fertilized carbon export for 3 events are presented. Patagonian iron supply to the Southern Ocean from volcanic eruptions is less than that of windblown dust on thousand year timescales but can dominate supply at shorter timescales. Reducing uncertainties in remote sensing of phytoplankton response and nutrient release from ash are avenues for enabling assessment of the oceanic response to large-scale transient nutrient enrichment.

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As part of the Sentinel-3 mission and in order to ensure the highest quality of products, ESA in cooperation with EUMETSAT has set up the Sentinel-3 Mission Performance Centre (S-3 MPC). This facility is part of the Payload Data Ground Segment (PDGS) and aims at controlling the quality of all generated products, from L0 to L2. The S-3 MPC is composed of a Coordinating Centre (CC), where the core infrastructure is hosted, which is in charge of the main routine activities (especially the quality control of data) and the overall service management. Expert Support Laboratories (ESLs) are involved in calibration and validation activities and provide specific assessment of the products (e.g., analysis of trends, ad hoc analysis of anomalies, etc.). The S-3 MPC interacts with the Processing Archiving Centres (PACs) and the Marine centre at EUMETSAT.

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Aims: To determine whether routine outpatient monitoring of growth predicts adrenal suppression in prepubertal children treated with high dose inhaled glucocorticoid.

Methods: Observational study of 35 prepubertal children (aged 4–10 years) treated with at least 1000 µg/day of inhaled budesonide or equivalent potency glucocorticoid for at least six months. Main outcome measures were: changes in HtSDS over 6 and 12 month periods preceding adrenal function testing, and increment and peak cortisol after stimulation by low dose tetracosactrin test. Adrenal suppression was defined as a peak cortisol 500 nmol/l.

Results: The areas under the receiver operator characteristic curves for a decrease in HtSDS as a predictor of adrenal insufficiency 6 and 12 months prior to adrenal testing were 0.50 (SE 0.10) and 0.59 (SE 0.10). Prediction values of an HtSDS change of –0.5 for adrenal insufficiency at 12 months prior to testing were: sensitivity 13%, specificity 95%, and positive likelihood ratio of 2.4. Peak cortisol reached correlated poorly with change in HtSDS ( = 0.23, p = 0.19 at 6 months; = 0.33, p = 0.06 at 12 months).

Conclusions: Monitoring growth does not enable prediction of which children treated with high dose inhaled glucocorticoids are at risk of potentially serious adrenal suppression. Both growth and adrenal function should be monitored in patients on high dose inhaled glucocorticoids. Further research is required to determine the optimal frequency of monitoring adrenal function.

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This paper investigated whether the SF-12 could replace the SF-36 in the measurement of health status among ischaemic heart disease patients. The SF-36 and SF-12 were administered to 105 cardiac patients. The SF-36 summary scores were strongly correlated and similar to the SF-12 summary scores. Also, the SF-12 scores were as powerful as the SF-36 summary scores in discriminating between subgroups of patients categorized according to their self-reported health status or angina classification. It is suggested that when there is a need to collect routine information about cardiac patients' general physical and mental health, the SF-12 is preferable to the SF-36 because of its brevity and acceptability to patients.

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Increasing emphasis is being placed on the evaluation of health-related quality of life. However, there is no consensus on the definition of this concept and as a result there are a plethora of existing measurement instruments. Head-to-head comparisons of the psychometric properties of existing instruments are necessary to facilitate evidence-based decisions about which instrument should be chosen for routine use. Therefore, an individualised instrument (the modified Patient Generated Index), a generic instrument (the Short Form 36) and a disease-specific instrument (the Quality of Life after Myocardial Infarction questionnaire) were administered to patients with ischaemic heart disease (n=117) and the evidence for the validity, reliability and sensitivity of each instrument was examined and compared. The modified Patient Generated Index compared favourably with the other instruments but none of the instruments examined provided sound evidence for sensitivity to change. Therefore, any recommendation for the use of the individualised approach in the routine collection of health-related quality of life data in clinical practice must be conditional upon the submission of further evidence to support the sensitivity of such instruments.

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OBJECTIVE: To determine the effect of dietary supplementation with omega-3 fish oils with or without copper on disease activity in systemic lupus erythematosus (SLE). Fish oil supplementation has a beneficial effect on murine models of SLE, while exogenous copper can decrease the formation of lupus erythematosus cells in rats with a hydralazine-induced collagen disease. METHODS: A double blind, double placebo controlled factorial trial was performed on 52 patients with SLE. Patients were randomly assigned to 4 treatment groups. Physiological doses of omega-3 fish oils and copper readily obtainable by dietary means were used. One group received 3 g MaxEPA and 3 mg copper, another 3 g MaxEPA and placebo copper, another 3 mg copper and placebo fish oil, and the fourth group received both placebo capsules. Serial measurements of disease activity using the revised Systemic Lupus Activity Measure (SLAM-R) and peripheral blood samples for routine hematological, biochemical, and immunological indices were taken at baseline, 6, 12, and 24 weeks. RESULTS: There was a significant decline in SLAM-R score from 6.12 to 4.69 (p <0.05) in those subjects taking fish oil compared to placebo. No significant effect on SLAM-R was observed in subjects taking copper. Laboratory variables were unaffected by either intervention. CONCLUSION: In the management of SLE, dietary supplementation with fish oil may be beneficial in modifying symptomatic disease activity.

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The use of apoptosis-inducing agents in the treatment of malignant cancer is increasingly being considered as a therapeutic approach. In this study, the induction of apoptosis and necrosis was examined in terms of temporal dose responses, comparing a malignant and nonmalignant breast cell line. Staurosporine (SSP)-induced apoptosis and H2O2-induced necrosis were evaluated by two cytotoxicity assays, neutral red (NR) and methyl-thiazolyl tertrazolium (MTT), in comparison with a differential dye uptake assay, using Hoechst33342/propidium iodide (Hoechst/PI). Confirmatory morphological assessment was also performed by routine resin histology and transmission electron microscopy. Cell viability was assessed over a 0.5-48 h time course. In nonmalignant HBL-100 cells, 50 nM SSP induced 100% apoptosis after a 48 h exposure, while the same exposure to SSP caused only 4% apoptosis in metastatic T47D cells. Although complete apoptosis of both cell lines was induced by 50 M SSP, this effect was delayed in T47D (24 h) compared with HBL-100 (4 h). Results also showed that neither MTT or NR can distinguish between the modes of cell death, nor detect the early onset of apoptosis revealed by Hoechst/PI.

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Conservators have long been aware of the problems associated with the preservation of rubber objects due to inherent instability that can be attributed, in part, to the presence of additives. Inorganic additives, such as fillers, accelerators, stabilizers, and special ingredients are necessary in manufacturing to alter the properties of natural rubber. These materials all have different interactions with the rubber, and each other, and differing effects on the ageing process. To date, the most effective and accepted methods to preserve rubber are cold, dark storage of objects, or the use of low oxygen environments. While these methods are effective, they greatly limit access. The application of coatings to the surface of rubber objects can slow deterioration and greatly increase the ability of an institution to handle and display rubber objects. While numerous coatings for preventive and interventive treatment have been tested, none have been so successful to warrant routine use. The first section of this research highlighted the relationship between the inclusion of certain additives in natural rubber objects and the accelerated or slowed down overall degradation. In the second part of this research, the acrylic varnishes Golden Polymer Varnish with UVLS, Lascaux Acrylic Transparent Varnish-UV, Sennelier Matte Lacquer with UV Protection, and Liquitex Soluvar Varnish containing ultraviolet light absorbers or stabilizers were tested as a preventative coating for rubber. Through testing the visual and physical properties of the samples, as well as compound analysis the results of this research suggest that acrylic varnishes do provide protection, each to varying degrees. The results also provided insight into the behavior of rubber and these varnishes with continuing light exposure.