9 research outputs found

    Functional Analysis of European Wetland Vegetation

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    Riverine marginal wetland vegetation was studied at thirty-two hydrogeomorphic units of sites used by the European Community project "Functional Analysis of European Wetland Ecosystems", these units were situated in England, France, Ireland and Spain. Fieldwork was carried out between May 1991 and August 1993. The aim of the work was to develop a system of analysis of wetland vegetation using functional attributes which could be used to predict the effect of anthropogenic perturbation. Grime's C-S-D established-phase strategy theory was used as the framework for this study. Analysis of plant species abundance, using DCA (detrended correspondence analysis) and PCA (principal components analysis), revealed the extent of variation in the plant species composition between the hydrogeomoq)hic units. A majority of the hydrogeomorphic units could be assigned to CORINE biotope categories (the European Community categorisation system of sites of nature conservation importance); most sites were water fringe vegetation (53) or humid grassland (37). Eight morphological traits were measured from one hundred and forty-four common plant populations from the hydrogeomorphic units. Non-hierarchical classification of populations by traits was carried out using sum of squares and centroid dissimilarity algorithms. It was determined that the most efficient classification was into three groups. Each of these three groups was associated with different parts of the C-S-D strategy space. The results strongly suggested that morphological traits can be used to classify plants into functional groups which have differing ecological properties. Using twelve traits, linear and multiple discriminant analysis were used to distinguish objectively between populations with a selected strategies determined from the work of Grime. Competitive and stress-tolerant populations were found to be significantly different using twelve traits. Stepwise multiple regression identified the important traits for predicting competitive ability (C) and stress tolerance (S). Significant predictors of the C-strategy were height of plant and the dry weight of leaves; and of the S strategy, the dry weight of stems and the weight per seed. Use of these predictive equations permitted calculation of C and S for the one hundred and forty-four populations that were studied. The mean C and S scores of the populations present in each hydrogeomorphic unit were used to determine the functional vegetation type (FVT) in terms of competitiveness (CFVT) and stress-tolerance (SFVT). CFVT and SFVT were inversely correlated (r = -0.73, P<0.001). A greenhouse experiment was carried out to determine the effect of competition (phytometer), disturbance (cutting) and stress (saturated soil conditions) on the morphology of six common wetland plants. The stress treatment was too weak to have much effect on the morphology of the species. The ranking of the species in terms of C and D (disturbance-tolerance) showed a degree of similarity with the strategy designation of Grime. The competitive ability of the test species, using the phytometr)' method, was significantly related to the field determined C score (r = 0.80, P<0.05). Eleven state variables, defined as measurable variables of biotic communities which have a particular range of values for each type of vegetational community, were measured in the studied wetlands. Using PCA, the major gradient in state variables was most strongly correlated to biomass. However, using CCA (canonical correspondence analysis), constraining the axes to be linear combinations of CFVT and SFVT, a different gradient in state variables was identified. This gradient was related to a high canopy, large stem area with great distance between stems and dominated by a few species at high CP/T-low SFVT values and high stem density, species richness and density of reproductive structures at low CFVT-high SFVT values. Using stepwise multiple regression, state variables could significantly predict CFVT (P<0.0001). Common CORINE biotopes were related to the CCA ordination diagram of FVT and state-variables. 3 biotopes (humid grassland, mesophile grassland and reed beds) were related to certain areas of the CFVT-SFVT gradient. Sedge beds ranged across much of the gradient, this could be due to the taxonomic diversity of the biotope. The results suggested a certain degree of comparability between the strategy, state-variable and phytosociological biotope units in the studied wetlands. (Abstract shortened by ProQuest.)

    Gazing over the horizon: Will an equitable Green Climate Fund allocation policy be significant for the Pacific post-2020?

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    The establishment of the Green Climate Fund (GCF) has increased expectations and optimism amongst developing countries, especially those that are particularly vulnerable to climate change. The GCF aims to channel a significant portion of global funds for climate change response, with a goal of reaching US$100 billion per year by 2020. Portrayed as a timely saviour to the climate finance needs of vulnerable countries, the allocation of GCF funds among countries will be key to low carbon and resilient futures. Its broad allocation policy increases the possibility that particularly vulnerable countries which have struggled to access international climate finance will continue to face such challenges. Adopting an equitable/fair principle of allocation, this article highlights a number of scenarios on the possible impact of the post-2020 climate financing environment on particularly vulnerable countries with a special focus on the Pacific Small Island Developing States (PSIDS). This study argues that PSIDS are extremely sensitive to GCF allocation mechanisms. While the study supports the notion of balanced allocation as currently advanced by the GCF, the precarious situation of PSIDS necessitates a re-think of how the GCF finance is to be allocated in the future

    Cool Pavements: State of the Art and New Technologies

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    With growing urban populations, methods of reducing the urban heat island effect have become increasingly important. Cool pavements altering the heat storage of materials used in pavements can lead to lower surface temperatures and reduce the thermal radiation emitted to the atmosphere. Cool pavement technologies utilize various strategies to reduce the temperature of new and existing pavements, including increased albedo, evaporative cooling, and reduced heat conduction. This process of negative radiation forces helps offset the impacts of increasing atmospheric temperatures. This paper presents an extensive analysis of the state of the art of cool pavements. The properties and principles of cool pavements are reviewed, including reflectivity, thermal emittance, heat transfer, thermal capacity, and permeability. The different types, research directions, and applications of reflective pavements are outlined and discussed. Maintenance and restoration technologies of cool pavements are reviewed, including permeable pavements. Results show that cool pavements have significant temperature reduction potential in the urban environment. This research is important for policy actions of the European Union, noting that European and international business stakeholders have recently expressed their interest in new ways of reducing energy consumption through technologically advanced pavements

    Prospective observational cohort study on grading the severity of postoperative complications in global surgery research

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    Background The Clavien–Dindo classification is perhaps the most widely used approach for reporting postoperative complications in clinical trials. This system classifies complication severity by the treatment provided. However, it is unclear whether the Clavien–Dindo system can be used internationally in studies across differing healthcare systems in high- (HICs) and low- and middle-income countries (LMICs). Methods This was a secondary analysis of the International Surgical Outcomes Study (ISOS), a prospective observational cohort study of elective surgery in adults. Data collection occurred over a 7-day period. Severity of complications was graded using Clavien–Dindo and the simpler ISOS grading (mild, moderate or severe, based on guided investigator judgement). Severity grading was compared using the intraclass correlation coefficient (ICC). Data are presented as frequencies and ICC values (with 95 per cent c.i.). The analysis was stratified by income status of the country, comparing HICs with LMICs. Results A total of 44 814 patients were recruited from 474 hospitals in 27 countries (19 HICs and 8 LMICs). Some 7508 patients (16·8 per cent) experienced at least one postoperative complication, equivalent to 11 664 complications in total. Using the ISOS classification, 5504 of 11 664 complications (47·2 per cent) were graded as mild, 4244 (36·4 per cent) as moderate and 1916 (16·4 per cent) as severe. Using Clavien–Dindo, 6781 of 11 664 complications (58·1 per cent) were graded as I or II, 1740 (14·9 per cent) as III, 2408 (20·6 per cent) as IV and 735 (6·3 per cent) as V. Agreement between classification systems was poor overall (ICC 0·41, 95 per cent c.i. 0·20 to 0·55), and in LMICs (ICC 0·23, 0·05 to 0·38) and HICs (ICC 0·46, 0·25 to 0·59). Conclusion Caution is recommended when using a treatment approach to grade complications in global surgery studies, as this may introduce bias unintentionally

    The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis

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    © 2017 British Journal of Anaesthesia Background: The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Methods: Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. Results: We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32–0.77); P\u3c0.01], but no difference in complication rates [OR 1.02 (0.88–1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62–0.92); P\u3c0.01; I2=87%] and reduced complication rates [OR 0.73 (0.61–0.88); P\u3c0.01; I2=89%). Conclusions: Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine

    Critical care admission following elective surgery was not associated with survival benefit: prospective analysis of data from 27 countries

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    This was an investigator initiated study funded by Nestle Health Sciences through an unrestricted research grant, and by a National Institute for Health Research (UK) Professorship held by RP. The study was sponsored by Queen Mary University of London
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