14,116 research outputs found
A comparison of sequential total and activated white cell count in patients undergoing coronary artery bypass grafting, using cardiopulmonary bypass, with and without a white cell filter
Introduction
Cardiopulmonary bypass (CPB) has been shown to induce a systemic inflammatory response similar to the local reaction seen after tissue damage [1]. This leads to the release of toxic substances, such as elastase, which cause endothelial damage and may adversely affect outcome [2]. Use of a leucocyte depleting arterial line filter is one of many anti-inflammatory strategies that are undergoing evaluation. Leucocyte depleting filters may be capable of selectively removing activated white cells [3], but this has not been proved in vivo. The aim of the present study was to compare sequential total and activated white cells during CPB, using either a leucocyte depleting or standard arterial line filter.
Materials and methods
After local ethical committee approval, 20 patients undergoing coronary artery bypass grafting using CPB were prospectively randomly allocated to have either a Leukogard LGâ6 (Pall Biomedical, Portsmouth, UK) or a nonleucocyte depleting filter inserted into the arterial line of the CPB circuit. Arterial limb blood samples were taken immediately after institution of CPB (0min) and at 10âmin intervals throughout the bypass period. Activated white cells were identified using nitroblue tetrazolium, then both total and activated white cell numbers counted after staining with Leucoplate.Results
Table 1 shows the number of white cells counted/1.25 ? l (volume of a single channel of Nageotte counting chamber) using light microscopy (Ă 25).Conclusion
The LG6 leucocyte filter reduces the total white cell count and is capable of selectively removing activated white cells during CPB. The exact relationship between leucocyte depletion and improved patient outcome still remains unclear
Learning the Designer's Preferences to Drive Evolution
This paper presents the Designer Preference Model, a data-driven solution
that pursues to learn from user generated data in a Quality-Diversity
Mixed-Initiative Co-Creativity (QD MI-CC) tool, with the aims of modelling the
user's design style to better assess the tool's procedurally generated content
with respect to that user's preferences. Through this approach, we aim for
increasing the user's agency over the generated content in a way that neither
stalls the user-tool reciprocal stimuli loop nor fatigues the user with
periodical suggestion handpicking. We describe the details of this novel
solution, as well as its implementation in the MI-CC tool the Evolutionary
Dungeon Designer. We present and discuss our findings out of the initial tests
carried out, spotting the open challenges for this combined line of research
that integrates MI-CC with Procedural Content Generation through Machine
Learning.Comment: 16 pages, Accepted and to appear in proceedings of the 23rd European
Conference on the Applications of Evolutionary and bio-inspired Computation,
EvoApplications 202
Transference of Transport Anisotropy to Composite Fermions
When interacting two-dimensional electrons are placed in a large
perpendicular magnetic field, to minimize their energy, they capture an even
number of flux quanta and create new particles called composite fermions (CFs).
These complex electron-flux-bound states offer an elegant explanation for the
fractional quantum Hall effect. Furthermore, thanks to the flux attachment, the
effective field vanishes at a half-filled Landau level and CFs exhibit
Fermi-liquid-like properties, similar to their zero-field electron
counterparts. However, being solely influenced by interactions, CFs should
possess no memory whatever of the electron parameters. Here we address a
fundamental question: Does an anisotropy of the electron effective mass and
Fermi surface (FS) survive composite fermionization? We measure the resistance
of CFs in AlAs quantum wells where electrons occupy an elliptical FS with large
eccentricity and anisotropic effective mass. Similar to their electron
counterparts, CFs also exhibit anisotropic transport, suggesting an anisotropy
of CF effective mass and FS.Comment: 5 pages, 5 figure
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Costs of switching to low global warming potential inhalers. An economic and carbon footprint analysis of NHS prescription data in England.
OBJECTIVES: Metered-dose inhalers (MDIs) contain propellants which are potent greenhouse gases. Many agencies propose a switch to alternative, low global warming potential (GWP) inhalers, such as dry powder inhalers (DPIs). We aimed to analyse the impact on greenhouse gas emissions and drug costs of making this switch. SETTING: We studied National Health Service prescription data from England in 2017 and collated carbon footprint data on inhalers commonly used in England. DESIGN: Inhalers were separated into different categories according to their mechanisms of action (eg, short-acting beta-agonist). Within each category we identified low and high GWP inhalers and calculated the cost and carbon impact of changing to low GWP inhalers. We modelled scenarios for swapping proportionally according to the current market share of each equivalent DPI (model 1) and switching to the lowest cost pharmaceutically equivalent DPI (model 2). We also reviewed available data on the carbon footprint of inhalers from scientific publications, independently certified reports and patents to provide more accurate carbon footprint information on different types of inhalers. RESULTS: If MDIs using HFA propellant are replaced with the cheapest equivalent DPI, then for every 10% of MDIs changed to DPIs, drug costs decrease by ÂŁ8.2M annually. However if the brands of DPIs stay the same as 2017 prescribing patterns, for every 10% of MDIs changed to DPIs, drug costs increase by ÂŁ12.7M annually. Most potential savings are due to less expensive long-acting beta-agonist (LABA)/inhaled corticosteroids (ICS) inhalers. Some reliever inhalers (eg, Ventolin) have a carbon footprint over 25 kg CO2e per inhaler, while others use far less 1,1,1,2-tetrafluoroethane (HFA134a) (eg, Salamol) with a carbon footprint of <10 kg CO2e per inhaler. 1,1,1,2,3,3,3-Heptafluoropropane (HFA227ea) LABA/ICS inhalers (eg, Flutiform) have a carbon footprint over 36 kg CO2e, compared with an equivalent HFA134a combination inhaler (eg, Fostair) at <20 kg CO2e. For every 10% of MDIs changed to DPIs, 58 kt CO2e could be saved annually in England. CONCLUSIONS: Switching to DPIs would result in large carbon savings and can be achieved alongside reduced drug costs by using less expensive brands. Substantial carbon savings can be made by using small volume HFA134a MDIs, in preference to large volume HFA134a MDIs, or those containing HFA227ea as a propellant.This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors
Assessment of valley cold pools and clouds in a very high-resolution numerical weather prediction model
The formation of cold air pools in valleys under stable conditions represents an important challenge for numerical weather prediction (NWP). The challenge is increased when the valleys that dominate cold pool formation are on scales unresolved by NWP models, which can lead to substantial local errors in temperature forecasts. In this study a 2-month simulation is presented using a nested model con- figuration with a finest horizontal grid spacing of 100 m. The simulation is compared with observations from the recent COLd air Pooling Experiment (COLPEX) project and the modelâs ability to represent cold pool formation, and the surface energy balance is assessed. The results reveal a bias in the model long-wave radiation that results from the assumptions made about the sub-grid variability in humidity in the cloud parametrization scheme. The cloud scheme assumes relative humidity thresholds below 100 % to diagnose partial cloudiness, an approach common to schemes used in many other models. The biases in radiation, and resulting biases in screen temperature and cold pool properties are shown to be sensitive to the choice of critical relative humidity, suggesting that this is a key area that should be improved for very high-resolution modeling
Episodic and binge gambling: an exploration and preliminary quantitative study
The DSM-5 includes provisions for episodic forms of gambling disorder, with such changes aligned with earlier accounts of potential binge gambling behaviours. However, there is little research that indicates the utility of these classifications of episodic or binge gambling, and this study considered their characteristics in a clinical sample. It involved administration of a new binge gambling screening tool, along with routine measures, to n = 214 patients entering a specialist treatment clinic for gambling problems. Results indicated that episodic gambling was common in this clinical context, with 28 and 32% of patients reporting gambling episodes that were (a) regular and alternating, and (b) irregular and intermittent, respectively. These patterns were distinguished by factors including associations with covariates that indicated differences from continuous gamblers. For example, the irregular episodic gamblers, but not the regular pattern, demonstrated lower levels of problem gambling severity and comorbidity. Rates of potential binge gambling, which was defined in terms of additional criteria, were around 4% and numbers were insufficient for comparable analyses. The findings support inclusion of episodic forms of gambling disorder in the DSM-5, but highlight the need for improved recognition and research on heterogeneous forms of episodic gambling
A caseâstudy of coldâair pool evolution in hilly terrain using field measurements from COLPEX
A caseâstudy investigation of coldâair pool (CAP) evolution in hilly terrain is conducted using field measurements made during IOP 16 of the COLdâair Pool EXperiment (COLPEX). COLPEX was designed to study coldâair pooling in smallâscale valleys typical of the UK (âŒ100â200âm deep, âŒ1âkm wide). The synoptic conditions during IOP 16 are typical of those required for CAPs to form during the night, with high pressure, clear skies and low ambient winds. Initially a CAP forms around sunset and grows uninterrupted for several hours. However, starting 4âhr after sunset, a number of interruptions to this steady cooling rate occur. Three episodes are highlighted from the observations and the cause of disruption attributed to (a) wave activity, in the form of gravity waves and/or KelvinâHelmholtz (KH) instability, (b) increases in the aboveâvalley winds resulting from the development of a nocturnal lowâlevel jet (NLLJ), (c) shearâinduced mixing resulting from instability of the NLLJ. A weakly stable residual layer provides the conditions for wave activity during Episode 1. This residual layer is eroded by a developing NLLJ from the top down during Episode 2. The sustained increase in winds at hillâtop levels â attributed to the NLLJ â continue to disrupt the CAP through Episode 3. Although cooling is interrupted, the CAP is never completely eroded during the night. Complete CAP breakâup occurs some 3.5âhr after local sunrise. This caseâstudy highlights a number of meteorological phenomena that can disrupt CAP evolution even in ideal CAP conditions. These processes are unlikely to be sufficiently represented by current operational weather forecast models and can be challenging even for highâresolution research models
The C-terminus of Bienertia sinuspersici Toc159 contains essential elements for its targeting and anchorage to the chloroplast outer membrane
Most nucleus-encoded chloroplast proteins rely on an N-terminal transit peptide (TP) as a post-translational sorting signal for directing them to the organelle. Although Toc159 is known to be a receptor for specific preprotein TPs at the chloroplast surface, the mechanism for its own targeting and integration into the chloroplast outer membrane is not completely understood. In a previous study, we identified a novel TP-like sorting signal at the C-terminus (CT) of a Toc159 homolog from the single-cell C4 species, Bienertia sinuspersici. In the current study, we have extended our understanding of the sorting signal using transient expression of fluorescently-tagged fusion proteins of variable-length, and with truncated and swapped versions of the CT. As was shown in the earlier study, the 56 residues of the CT contain crucial sorting information for reversible interaction of the receptor with the chloroplast envelope. Extension of this region to 100 residues in the current study stabilized the interaction via membrane integration, as demonstrated by more prominent plastid-associated signals and resistance of the fusion protein to alkaline extraction. Despite a high degree of sequence similarity, the plastid localization signals of the equivalent CT regions of Arabidopsis thaliana Toc159 homologs were not as strong as that of the B. sinuspersici counterparts. Together with computational and circular dichroism analyses of the CT domain structures, our data provide insights into the critical elements of the CT for the efficient targeting and anchorage of Toc159 receptors to the dimorphic chloroplasts in the single-cell C4 species.published_or_final_versio
SeaWiFS satellite ocean color data from the Southern Ocean
SeaWiFS estimates of surface chlorophyll concentrations are reported for the region of the U.S. JGOFS study in the Southern Ocean (similar to 170 degrees W, 60 degrees S). Elevated chlorophyll was observed at the Southern Ocean fronts, near the edge of the seasonal ice sheet, and above the Pacific-Antarctic Ridge. The elevated chlorophyll levels associated with the Pacific-Antarctic Ridge are surprising since even the crest of the ridge is at depths \u3e 2000 m. This elevated phytoplankton biomass is likely the result of mesoscale physical-biological interactions where the Antarctic Circumpolar Current (ACC) encounters the ridge. Four cruises surveyed this region between October 1997 and March 1998, as part of the U.S. JGOFS. Satellite-derived chlorophyll concentrations were compared with in situ extracted chlorophyll measurements from these cruises. There was good agreement (r(2) of 0.72, from a linear regression of shipboard vs, satellite chlorophyll), although SeaWiFS underestimated chlorophyll concentrations relative to the ship data
Exploring the behavioural drivers of veterinary surgeon antibiotic prescribing: a qualitative study of companion animal veterinary surgeons in the UK
Background:
Multi-drug resistant bacteria are an increasing concern in both human and veterinary medicine. Inappropriate prescribing and use of antibiotics within veterinary medicine may be a contributory factor to antimicrobial resistance (AMR). The âOne Healthâ Initiative aims to work across species and environments to reduce AMR, however; little is currently known about the factors which influence antibiotic prescribing among veterinary surgeons in companion animal practice.
This paper reports on qualitative data analysis of interviews with veterinary surgeons whose practice partially or wholly focuses on companion animals (N =â16). The objective of the research was to explore the drivers of companion animal veterinary surgeonsâ antibiotic prescribing behaviours. The veterinary surgeons interviewed were all practising within the UK (England (n =â4), Scotland (n =â11), Northern Ireland (n =â1)). A behavioural thematic analysis of the data was undertaken, which identified barriers and facilitators to specific prescribing-related behaviours.
Results:
Five components of prescribing behaviours were identified: 1) confirming clinical need for antibiotics; 2) responding to clients; 3) confirming diagnosis; 4) determining dose, duration and type of antibiotic; and 5) preventing infection around surgery (with attendant appropriate and inappropriate antibiotic prescribing behaviours). Barriers to appropriate prescribing identified include: business, diagnostic, fear, habitual practice and pharmaceutical factors. Facilitators include: AMR awareness, infection prevention, professional learning and regulation and government factors.
Conclusion:
This paper uses a behavioural lens to examine drivers which are an influence on veterinary surgeonsâ prescribing behaviours. The paper contributes new understandings about factors which influence antibiotic prescribing behaviours among companion animal veterinary surgeons. This analysis provides evidence to inform future interventions, which are focused on changing prescribing behaviours, in order to address the pressing public health concern of AMR
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