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881.
Georgios Karris Aristotelis Martinis Katerina Kabassi Aggeliki Dalakiari Malamo Korbetis 《Journal of biological education》2020,54(2):162-175
ABSTRACTThe current study aims at monitoring, measuring and evaluating the ‘Safe havens for wild birds’ campaign, implemented within the framework of the LIFE programme, in Greece and more specifically in the Ionian Islands. The study detects attitude changes that occurred in three target groups (pupils, local hunters and residents) on three islands where the phenomenon of illegal spring killing is more intense. A questionnaire-based survey was conducted in two phases, just before the launch (2013) and after the completion of the campaign (2015), to enable a comparison of answers and data. The results show that pupils and to a lesser extent residents, enhanced their knowledge and awareness of poaching, the migration of avifauna and the consequences of illegal killing on migratory birds, while this aspect of attitude change was not observed in the hunting community which still believes that spring poaching should be treated as a legal activity and part of local culture. 相似文献
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883.
Winnie Chua Jonathan P. Law Victor R. Cardoso Yanish Purmah Georgiana Neculau Muhammad Jawad-Ul-Qamar Kalisha Russell Ashley Turner Samantha P. Tull Frantisek Nehaj Paul Brady Peter Kastner Andr Ziegler Georgios V. Gkoutos Davor Pavlovic Charles J. Ferro Paulus Kirchhof Larissa Fabritz 《PLoS medicine》2021,18(2)
BackgroundLarge-scale screening for atrial fibrillation (AF) requires reliable methods to identify at-risk populations. Using an experimental semi-quantitative biomarker assay, B-type natriuretic peptide (BNP) and fibroblast growth factor 23 (FGF23) were recently identified as the most suitable biomarkers for detecting AF in combination with simple morphometric parameters (age, sex, and body mass index [BMI]). In this study, we validated the AF model using standardised, high-throughput, high-sensitivity biomarker assays.Methods and findingsFor this study, 1,625 consecutive patients with either (1) diagnosed AF or (2) sinus rhythm with CHA2DS2-VASc score of 2 or more were recruited from a large teaching hospital in Birmingham, West Midlands, UK, between September 2014 and February 2018. Seven-day ambulatory ECG monitoring excluded silent AF. Patients with tachyarrhythmias apart from AF and incomplete cases were excluded. AF was diagnosed according to current clinical guidelines and confirmed by ECG. We developed a high-throughput, high-sensitivity assay for FGF23, quantified plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) and FGF23, and compared results to the previously used multibiomarker research assay. Data were fitted to the previously derived model, adjusting for differences in measurement platforms and known confounders (heart failure and chronic kidney disease). In 1,084 patients (46% with AF; median [Q1, Q3] age 70 [60, 78] years, median [Q1, Q3] BMI 28.8 [25.1, 32.8] kg/m2, 59% males), patients with AF had higher concentrations of NT-proBNP (median [Q1, Q3] per 100 pg/ml: with AF 12.00 [4.19, 30.15], without AF 4.25 [1.17, 15.70]; p < 0.001) and FGF23 (median [Q1, Q3] per 100 pg/ml: with AF 1.93 [1.30, 4.16], without AF 1.55 [1.04, 2.62]; p < 0.001). Univariate associations remained after adjusting for heart failure and estimated glomerular filtration rate, known confounders of NT-proBNP and FGF23. The fitted model yielded a C-statistic of 0.688 (95% CI 0.656, 0.719), almost identical to that of the derived model (C-statistic 0.691; 95% CI 0.638, 0.744). The key limitation is that this validation was performed in a cohort that is very similar demographically to the one used in model development, calling for further external validation.ConclusionsAge, sex, and BMI combined with elevated NT-proBNP and elevated FGF23, quantified on a high-throughput platform, reliably identify patients with AF.Trial registrationRegistry IRAS ID 97753 Health Research Authority (HRA), United KingdomWinnie Chua and colleagues identify and validate biomarkers for atrial fibrillation 相似文献
884.
Pumpkin pectin: gel formation at unusually low concentration 总被引:2,自引:0,他引:2
Nataliya M. Ptitchkina Irina A. Danilova Georgios Doxastakis Stefan Kasapis Edwin R. Morris 《Carbohydrate polymers》1994,23(4):265-273
The gel properties of high-methoxy pectin from pumpkins have been investigated to assess the potential of this material as a hard-currency export from the former Soviet Union. Comparison was made with commercial slow-set, medium-set and rapid-set pectins from citrus peel. Gels were formed by cooling pectin solutions (pH 3·0; 60% (w/w) sucrose; 5% (w/w) corn syrup) from 95°C to 25°C, and the time-temperature course of network formation was monitored by small-deformation oscillatory measurements of storage modulus (G′). At concentrations above 1% (w/w) the pumpkin pectin gave weaker gels than the other three samples, but its minimum critical gelling concentration (c0) was found to be much lower (by at least a factor of five). Compression testing gave similar results, with pumpkin pectin giving useful breaking-stress (‘hardness’) at concentrations down to 0·5% (w/w), about a factor of two lower than for the citrus samples. Its gelation was also less rapid, giving G′ values below those of the other three samples at temperatures down to 60°C, but then setting sharply; this behaviour could be useful in avoiding ‘pregelation’ in commercial processing. The commercial slow-set pectin showed typical ‘weak gel’ properties in the solution state at 95°C, with systematic reduction in gel-like character with increasing ester content in the other samples. The rigidity of the final gels also decreased systematically through the series: rapid-set < medium-set < slow-set. These observations are tentatively ascribed to stable association of unesterified galacturonate chain segments at low pH, where electrostatic repulsion is suppressed. 相似文献
885.
886.
Fraser Aitken Georgios Menelaou Oliver Warrington Rene S. Koolschijn Nadge Corbin Martina F. Callaghan Peter Kok 《PLoS biology》2020,18(12)
The way we perceive the world is strongly influenced by our expectations. In line with this, much recent research has revealed that prior expectations strongly modulate sensory processing. However, the neural circuitry through which the brain integrates external sensory inputs with internal expectation signals remains unknown. In order to understand the computational architecture of the cortex, we need to investigate the way these signals flow through the cortical layers. This is crucial because the different cortical layers have distinct intra- and interregional connectivity patterns, and therefore determining which layers are involved in a cortical computation can inform us on the sources and targets of these signals. Here, we used ultra-high field (7T) functional magnetic resonance imaging (fMRI) to reveal that prior expectations evoke stimulus-specific activity selectively in the deep layers of the primary visual cortex (V1). These findings are in line with predictive processing theories proposing that neurons in the deep cortical layers represent perceptual hypotheses and thereby shed light on the computational architecture of cortex.The way we perceive the world is strongly influenced by our expectations, but the neural circuitry through which the brain achieves this remains unknown. A study using ultra-high field fMRI reveals that prior expectations evoke stimulus-specific signals in the deep layers of the primary visual cortex. 相似文献