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Aim: The aims of this study were to explore the outcome measures that can be recorded in a radiotherapy IT system and the extract mortality results for a group of patients receiving radical radiotherapy treatment for primary brain cancer. Method: Treatment mortality outcomes were extracted from a radiotherapy database and were compared to treatment technique used between 1 January 2011 and 31 December 2017. The patients selected received 1 course of radiotherapy of 60 Gray in 30 treatments (n = 270). These patients received either Conformal Radiotherapy (CRT) (n = 127) or Volumetric Modulated Arc Therapy (VMAT) (n = 143). Kaplan–Meier plots were generated for these two groups to assess the survival. The median survival was 20·1 months (95%CI = 16·8−23·4) and 14·0 months (95%CI = 11·1−16·5) for CRT and VMAT, respectively. Discussion: Surprisingly, the results of this data extraction demonstrated that CRT gave better survival for this group of patients, than VMAT. The reason for the difference in survival is unclear and more data are needed to explain the result. Conclusion: This demonstrates that not only that a radiotherapy database can be used to extract outcome measures but that it must be done to explore where a change in treatment delivery has been of benefit to the patients or not. [ABSTRACT FROM AUTHOR]

Aim The aim was to quantify the influence of urban land use and urban populations on mangrove systems around the world over the past four decades. Location Global. Time period 1997-2015. Major taxa studied Avicennia, Laguncularia, Rhizophora, Aves, Actinopterygii, Crustacea and Mollusca. Methods This review extracts results of mangrove studies on forest cover and structure, nutrient dynamics, sediment contamination and faunal community assemblages conducted around the world between 1997 and 2015. These observations are then correlated with surrounding social-ecological spatial characteristics pertaining to urbanization. Results Mangrove coverage in large cities is mostly decreasing, and at a greater rate than means for corresponding countries. Both expanding urbanization and existing agriculture are most strongly correlated with mangrove losses, which are primarily occurring 5-10 km from urban areas. Along a gradient of surrounding urban land use, mangrove leaf δ15N content increases, and leaf carbon to nitrogen ratios decrease. Sediment concentrations of almost all examined heavy metals are strongly and positively correlated with both surrounding urban and mangrove extent. The diversity of subsistence fisheries increases significantly with surrounding mangrove extent. Worm diversity decreases with increasing surrounding urbanness (urban index), and mangrove specialist bird diversity increases with increasing surrounding urban coverage as well as with mangrove coverage. Main conclusions Mangroves increasingly coexist within highly anthropogenic landscapes along urbanized coasts. Most ecological reports of these systems, however, lack quantified representations of the urban landscape, such as population density or impervious surface coverage. The results of this analysis suggest that some of the reported patterns of forest coverage, nitrogen dynamics, heavy metal contamination and faunal community assemblages in isolated urban mangroves are systemic across the world. These findings are particularly pertinent to 21st century tropical coastlines, which will see some of the greatest urbanization rates over the next century and will guide urban mangrove ecology towards the development of more synergistic social-ecological systems. [ABSTRACT FROM AUTHOR]

Aim Terrestrial ecosystems have sequestered, on average, the equivalent of 30% of anthropogenic carbon (C) emissions during the past decades, but annual sequestration varies from year to year. For effective C management, it is imperative to develop a predictive understanding of the interannual variability (IAV) of terrestrial net ecosystem C exchange (NEE). Location Global terrestrial ecosystems. Methods We conducted a comprehensive review to examine the IAV of NEE at global, regional and ecosystem scales. Then we outlined a conceptual framework for understanding how anomalies in climate factors impact ecological processes of C cycling and thus influence the IAV of NEE through biogeochemical regulation. Results The phenomenon of IAV in land NEE has been ubiquitously observed at global, regional and ecosystem scales. Global IAV is often attributable to either tropical or semi-arid regions, or to some combination thereof, which is still under debate. Previous studies focus on identifying climate factors as driving forces of IAV, whereas biological mechanisms underlying the IAV of ecosystem NEE are less clear. We found that climate anomalies affect the IAV of NEE primarily through their differential impacts on ecosystem C uptake and respiration. Moreover, recent studies suggest that the carbon uptake period makes less contribution than the carbon uptake amplitude to IAV in NEE. Although land models incorporate most processes underlying IAV, their efficacy to predict the IAV in NEE remains low. Main conclusions To improve our ability to predict future IAV of the terrestrial C cycle, we have to understand biological mechanisms through which anomalies in climate factors cause the IAV of NEE. Future research needs to pay more attention not only to the differential effects of climate anomalies on photosynthesis and respiration but also to the relative importance of the C uptake period and amplitude in causing the IAV of NEE. Ultimately, we need multiple independent approaches, such as benchmark analysis, data assimilation and time-series statistics, to integrate data, modelling frameworks and theory to improve our ability to predict future IAV in the terrestrial C cycle. [ABSTRACT FROM AUTHOR]

Aim Scientists, governments and non-governmental organizations are increasingly moving towards the collection of large, open-access data. In aquatic sciences, this effort is expanding the scope of questions and analyses that can be performed to further our knowledge of the global drivers of water quality. Cyanotoxin concentration is one variable that has received considerable attention, and although strong local-scale models have been described in the literature, modelling cyanotoxin concentrations across broader spatial scales has been more difficult. Commonly used statistical frameworks have not fully captured the complex response of toxic algal blooms to global change, limiting our ability to predict and mitigate the impairment of freshwaters by toxic algae. Here, we advance our understanding of emergent drivers of cyanotoxins across a structured landscape by applying a hierarchical 'hurdle' model. Location Lakes and reservoirs in the conterminous United States [ n = 1127]. Methods We studied cyanobacteria and their toxins [microcystins] during the 2007 summer period. We applied a hierarchical zero-altered model to test the importance of multi-scale interactions among environmental features in driving microcystin concentrations above the limit of detection. We then used boosted regression trees [BRTs] to identify environmental thresholds associated with severe impairment by microcystins. Results Accounting for numerous non-detections, spatial heterogeneity and cross-scale interactions substantially improved continental-scale predictions of bloom toxicity. Our model accounted for 55% of the variance in the probability of detecting microcystins across the United States, and 26% of the variability in microcystin concentrations once detected. BRTs further showed that although both local and regional drivers were associated with microcystin concentrations at low to intermediate provisional guidelines, only local drivers came into play when predicting higher limits. Main conclusions Identifying the interaction between local and regional processes is key to understanding the heterogeneous responses of microcystins to environmental change. Our framework could increase the effectiveness of continental-scale analyses for many different water variables. [ABSTRACT FROM AUTHOR]

Aim To use global databases to (1) provide a visualization of global geographical patterns of species invasions, origins and pathways and (2) depict the international uptake of legislative and policy responses to invasive alien species (IAS). Location Global. Methods Patterns of recorded species invasions and pathways of introduction were mapped and visualized using data from the Global Invasive Species Database (GISD) and the CABI Invasive Species Compendium (CABI ISC), along with associated legal instruments relevant to IAS compiled from the ECOLEX database. A novel indicator of the asymmetry between each country's 'ingress/egress' of IAS (kappa, K), was developed to further explore spatial patterns. Results Substantial variation in the spatial patterns of invasion was determined, with the Global North, some newly industrialized countries and small tropical islands being the main recipients of IAS and asymmetry (K) being highest in New World countries and small islands. Of the 1517 recorded IAS, 39% were introduced only intentionally and 26% only unintentionally, 22% both intentionally and unintentionally, while 13% had no information available. The dominant pathway for species invasions was horticulture and the nursery trade, with 31% of the species introduced outside of their natural geographical range. Large increases in legislation on IAS have occurred since the 1990s, particularly for those countries that have high numbers of species invasions. Main conclusions Clear global patterns in the distributions of IAS are determined, supporting arguments emphasizing the role of colonial history, economic development and trade in driving the human-mediated movement of species. Dominant pathways for species invasions are similar across different regions. Policy responses towards IAS show an increasing desire from the international community to act on species invasions. Current patterns suggest that Africa and Central Asia are priority areas for future IAS research and control. [ABSTRACT FROM AUTHOR]

Aim The 'two sides of the same coin' hypothesis posits that biological traits that predispose species to extinction and invasion lie on opposite ends of a continuum. Conversely, anthropogenic factors may have similar effects on extinction and invasion risk. We test these two hypotheses using data on more than 1000 reptile species. Location Global. Methods We used hierarchical Bayesian models to determine whether biological traits and anthropogenic factors were correlated with whether a species was: (1) listed as Threatened versus Least Concern on the IUCN Red List, and (2) successful versus unsuccessful at establishing a viable population once introduced outside of its native geographical range. The 'two sides of the same coin' hypothesis predicts that model coefficients for each trait should be opposite in sign between these two models. Results Seventy-three per cent of model coefficients describing 10 aspects of a species' life history, ecology, biogeography and environmental niche breadth were opposite in sign between the two groups; however, most effect sizes for variables that showed contrasting relationships were small and/or uncertain. The only exception was body size: larger-bodied species were more likely to be threatened, whereas smaller-bodied species were more likely to be invasive. As predicted, human population density across a species' native geographical range was positively correlated with both threat and invasion probabilities. Other anthropogenic variables did not have strong analogous effects. Main conclusions The assumption that threatened and invasive species lie on opposite ends of a continuum, while consistent with life-history theory, appears to be an oversimplification. Our results do suggest, however, that anthropogenic variables can be important predictors of a species' fate, and should be more routinely incorporated in trait-based analyses of extinction and invasion risk. [ABSTRACT FROM AUTHOR]

Aim Terrestrial invertebrates comprise a large proportion of alien species world-wide, yet a quantitative global synthesis of their effects on native species and ecosystems has not been explored. We conducted a meta-analysis to examine the ecological impacts of terrestrial invertebrate invaders and to test how impacts are modulated by the invader's trophic position, habitat attributes (i.e. insularity and disturbance) and the study methodology (observational versus experimental). Location Global. Methods We investigated the effects of terrestrial invertebrate invaders on populations, communities and ecosystems by conducting a random effects meta-analysis using 112 articles reporting data from 710 field and laboratory studies. The analysis included 16 insect, 11 earthworm, 7 slug and 1 nematode invaders. Results On average, across invaders, the presence of invaders reduced plant fitness (52%), animal diversity (33%) and animal abundance (29%). Leaf litter decomposition was 41% higher in the presence of invaders, while other ecosystem-level variables such as nutrient cycling were not affected in a consistent direction. Invasive predators and detritivores decreased animal abundance, whereas herbivores and omnivores had limited impacts. Single invaders increased soil nitrogen pools while multiple species did not. Insularity and disturbance did not affect the magnitude of the impacts significantly, mainly because there was a large variation among studies. Main conclusions Overall, our study indicates that terrestrial invertebrate invaders have significant consistent effects on populations, communities and ecosystems, with islands and disturbed sites not being more prone to impacts. However, effects vary considerably depending on the type of impact being examined and the trophic position of the invader. There is no evidence that invaders cause larger impacts when multiple species of invaders, rather than single invaders, are involved. [ABSTRACT FROM AUTHOR]

Aim The relative contribution of community functional diversity and composition to ecosystem functioning is a critical question in ecology in order to enable better predictions of how ecosystems may respond to a changing climate. However, there is little consensus about which modes of functional biodiversity are most important for tree growth at large spatial scales. Here we assessed the relative importance of climate, functional diversity and functional identity (i.e. the community mean values of four key functional traits) for tree growth across the European continent, spanning the northern boreal to the southern Mediterranean forests. Location Finland, Germany, Sweden, Spain and Wallonia ( Belgium). Methods Using data from five European national forest inventories we applied a hierarchical linear model to estimate the sensitivity of tree growth to changes in climate, functional diversity and functional identity along a latitudinal gradient. Results Functional diversity was weakly related to tree growth in the temperate and boreal regions and more strongly in the Mediterranean region. In the temperate region, where climate was the most important predictor, functional diversity and identity had a similar importance for tree growth. Functional identity was strongest at the latitudinal extremes of the continent, largely driven by strong changes in the importance of maximum height along the latitudinal gradient. Main conclusions Functional diversity is an important driver of tree growth in the Mediterranean region, providing evidence that niche complementarity may be more important for tree growth in water-limited forests. The strong influence of functional identity at the latitudinal extremes indicates the importance of a particular trait composition for tree growth in harsh climates. Furthermore, we speculate that this functional identity signal may reflect a trait-based differentiation of successional stages rather than abiotic filtering due to water or energy limitation. [ABSTRACT FROM AUTHOR]

Aim To assess the effects of climate change, past land uses and physiography on the current position of the tree line in the Catalan Pyrenees and its dynamics between 1956 and 2006. Location More than 1000 linear kilometres of sub-alpine tree line in the Catalan Pyrenees (north-east Spain) Methods Using aerial photographs and supervised classification, we reclassified the images into a binary raster with 'tree' and 'non-tree' values, and determined canopy cover in 1956 and 2006. We then determined the change in position of the tree line between 1956 and 2006 based on changes in forest cover. We used the distance from the position of the tree line in 1956 to the theoretical potential tree line - determined from interpretation of aerial photographs, identifying the highest old remnants of forest for homogeneous areas of the landscape in terms of bioclimatic conditions, bedrock, landform and exposure - as a surrogate of intensity of past land uses. Results Our analyses showed that the Pyrenean tree line has moved upwards on average almost 40 m (mean advance ± SE: 35.3 ± 0.5 m, P < 0.001), although in most cases it has remained unchanged (61.8%) or advanced moderately, i.e. between 25 and 100 m (23.7%); only 9.2% of the locations have advanced more than 100 m. Upward shifts of the tree line were significantly larger in locations heavily modified in the past by anthropogenic disturbance (mean advance 50.8 ± 1.1 m) compared with near natural tree line locations (19.7 ± 0.8 m, P < 0.001), where the mean displacement was much lower than expected and was not related to changes in temperature along the study period. Main conclusions Our results stress the impact of the cessation of human activity in driving forest dynamics at the tree line in the Catalan Pyrenees, and reveal a very low or even negligible signal of climate change in the study area. [ABSTRACT FROM AUTHOR]