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Extracellular volume fraction improves risk-stratification for ventricular arrhythmias and sudden death in non-ischemic cardiomyopathy.
No full textObjectivesTo evaluate whether CMR-based parametric mapping and strain analysis can improve the risk-stratification for ventricular arrhythmias (VA) and sudden death (SD) in non-ischemic cardiomyopathy (NICM). Methods and resultsSecondary analysis of a prospective single-centre-registry (NCT02326324), including 703 consecutive NICM patients, 618 with extracellular volume (ECV) available. The combined primary endpoint included appropriate implantable cardioverter defibrillator therapies, sustained ventricular tachycardia, resuscitated cardiac arrest and SD. During a median follow-up of 21 months, 14 patients (2%) experienced the primary endpoint. Native T1 was not associated with the primary endpoint. Left ventricular global longitudinal strain lost its significant association after adjustment for left ventricular ejection fraction (LVEF). Among patients with ECV available, 11 (2%) reached the primary endpoint. Mean ECV was significantly associated with the primary endpoint and the best cut-off was 30%. ECV≥30% was the strongest independent predictor of the primary endpoint (HR 14.1, p=0.01) after adjustment for LGE and LVEF. ECV≥30% discriminated the arrhythmic risk among LGE+ cases and among those with LVEF≤35%. A simple clinical risk-stratification model, based on LGE, LVEF≤35% and ECV≥30%, achieved an excellent predictive ability (Harrell’s C 0.82) and reclassified the risk of 32% of the study population as compared to LVEF≤35% alone. Conclusions Comprehensive CMR evaluation in NICM showed that ECV was the only parameter with an independent and strong predictive value for VA/SD, on top of LGE and LVEF. A risk-stratification model based on LGE, LVEF≤35% and ECV≥30% achieved an excellent predictive ability for VA/SD
Optimised cell growth and poly(3-hydroxybutyrate) synthesis from saponified spent coffee grounds oil
No full textSpent coffee grounds (SCG) oil is an ideal substrate for the biosynthesis of polyhydroxyalkanoates (PHAs) by Cupriavidus necator. The immiscibility of lipids with water limits their bioavailability, but this can be resolved by saponifying the oil with potassium hydroxide to form water-soluble fatty acid potassium salts and glycerol. Total saponification was achieved with 0.5 mol/L of KOH at 50 °C for 90 min. The relationship between the initial carbon substrate concentration (C0) and the specific growth rate (µ) of C. necator DSM 545 was evaluated in shake flask cultivations; crude and saponified SCG oils were supplied at matching initial carbon concentrations (C0 = 2.9-23.0 g/L). The Han-Levenspiel model provided the closest fit to the experimental data and accurately described complete growth inhibition at 32.9 g/L (C0 = 19.1 g/L) saponified SCG oil. Peak µ-values of 0.139 h−1 and 0.145 h−1 were obtained with 11.99 g/L crude and 17.40 g/L saponified SCG oil, respectively. Further improvement to biomass production was achieved by mixing the crude and saponified substrates together in a carbon ratio of 75:25% (w/w), respectively. In bioreactors, C. necator initially grew faster on the mixed substrates (µ = 0.35 h−1) than on the crude SCG oil (µ = 0.23 h−1). After harvesting, cells grown on crude SCG oil obtained a total biomass concentration of 7.8 g/L and contained 77.8 % (w/w) PHA. Whereas cells grown on the mixed substrates produced 8.5 g/L of total biomass and accumulated 84.4 % (w/w) of PHA
Elucidating Heterogeneous Iron Biomineralization Patterns in a Denitrifying As(III)-Oxidizing Bacterium: Implications for Arsenic Immobilization
No full textAnaerobic nitrate-dependent iron(II) oxidation is a process common to many bacterial species, which promotes the formation of Fe(III) minerals that can influence the fate of soil and groundwater pollutants, such as arsenic. Herein, we investigated simultaneous nitrate-dependent Fe(II) and As(III) oxidation by Acidovorax sp. strain ST3 with the aim of studying the Fe biominerals formed, their As immobilization capabilities and the metabolic effect on cells. X-ray powder diffraction (XRD) and scanning transmission electron microscopy (STEM) nanodiffraction were applied for biomineral characterization in bulk and at the nanoscale, respectively. NanoSIMS (nanoscale secondary ion mass spectrometry) was used to map the intra and extracellular As and Fe distribution at the single-cell level and to trace metabolically active cells, by incorporation of a 13C-labeled substrate (acetate). Metabolic heterogeneity among bacterial cells was detected, with periplasmic Fe mineral encrustation deleterious to cell metabolism. Interestingly, Fe and As were not co-localized in all cells, indicating delocalized sites of As(III) and Fe(II) oxidation. The Fe(III) minerals lepidocrocite and goethite were identified in XRD, although only lepidocrocite was identified via STEM nanodiffraction. Extracellular amorphous nanoparticles were formed earlier and retained more As(III/V) than crystalline “flakes” of lepidocrocite, indicating that longer incubation periods promote the formation of more crystalline minerals with lower As retention capabilities. Thus, the addition of nitrate promotes Fe(II) oxidation and formation of Fe(III) biominerals by ST3 cells which retain As(III/V), and although this process was metabolically detrimental to some cells, it warrants further examination as a viable mechanism for As removal in anoxic environments by biostimulation with nitrate
Review of 'Harnessing Public Research for Innovation in the 21st Century: An International Assessment of Knowledge Transfer Policies. Edited by: Anthony Arundel, Suma Athreye and Sacha Wunsch-Vincent Cambridge and the World Intellectual Property Organization. Cambridge, United Kingdom. 2021. 502 pp. ISBN 9781108842792'
No full textControlling desolvation through polymer-assisted grinding
No full textWe demonstrate the ability to controllably desolvate a crystal-solvate system in step-wise fashion through polymer-assisted grinding by varying the type and proportion of polymer agent used. A plausible mechanistic explanation is proposed based on a combination of experimental evidence and computational analysis. Specifically, Raman spectroscopy, total scattering pair distribution function analysis and computed reaction energies suggest that the desolvation process is associated with preferred interactions between the solvent molecules and specific polymers. This approach could potentially be extended to any type of material, including heat-sensitive materials, where classical desolvation by thermal processes is not possible, and provides a new potential technique for formulation processing
ESBMC-Jimple: Verifying Kotlin Programs via Jimple Intermediate Representation
No full textIn this work, we describe and evaluate the first model checker for verifying Kotlin programs through the Jimple intermediate representation. The verifier, named ESBMC-Jimple, is built on top of the Efficient SMT-based Context-Bounded Model Checker (ESBMC). It uses the Soot framework to obtain the Jimple IR, representing a simplified version of the Kotlin source code, containing a maximum of three operands per instruction. ESBMC-Jimple processes Kotlin source code together with a model of the standard Kotlin libraries and checks a set of safety properties. Experimental results show that ESBMC-Jimple can correctly verify a set of Kotlin benchmarks from the literature and that it is competitive with state-of-theart Java bytecode verifiers. A demonstration is available at https://youtu.be/J6WhNfXvJNc
Energy Efficiency Optimization for PSOAM Mode-Groups based MIMO-NOMA Systems
No full textPlane spiral orbital angular momentum (PSOAM) mode-groups (MGs) and multiple-input multiple-output nonorthogonal multiple access (MIMO-NOMA) serve as two emerging techniques for achieving high spectral efficiency (SE) in the next-generation networks. In this paper, a PSOAM MGs based multi-user MIMO-NOMA system is studied, where the base station transmits data to users by utilizing the generated PSOAM beams. For such scenario, the interference between users in different PSOAM mode groups can be avoided, which leads to a significant performance enhancement. We aim to maximize the energy efficiency (EE) of the system subject to the constraints of the total transmission power and the minimum data rate. This designed optimization problem is non-convex owing to the interference among users, and hence is quite difficult to tackle directly. To solve this issue, we develop a dual layer resource allocation algorithm where the bisection method is exploited in the outer layer to obtain the optimal EE and a resource distributed iterative algorithm is exploited in the inner layer to optimize the transmit power. Besides, an alternative resource allocation algorithm with Deep Belief Networks (DBN) is proposed to cope with the requirement for low computational complexity. Simulation results verify the theoretical findings and demonstrate the proposed algorithms on the PSOAM MGs based MIMO-NOMA system can obtain a better performance comparing to the conventional MIMO-NOMA system in terms of EE