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One factor with great bearing on the electrochemical performance of conjugated polymers is the film morphology. A balance between crystalline and amorphous domains needs to be achieved for the polymer to have an optimal ionic-electronic conductance. Herein, the morphological and electrochemical properties of poly(ethylenedioxythiophene) polymers functionalized with phosphonate groups separated by methylene and butylene alkyl spacers from the backbone are compared. Extending the spacer from methylene to butylene increases structural ordering in the solid state as revealed by grazing-incidence wide-angle X-ray scattering. However, the ordered domains are only short range, suggestive of a paracrystalline morphology in which ordered regions are separated by amorphous regions. This has a negative impact on the intermolecular charge transport. The longer spacer appears to have impeded the uptake of hydrated counterions, seen by the increase in the ionization potential and energy requirement for electrochemical switching, as well as the decrease in the volumetric capacitance. These results elucidate the advantages of having the phosphonate pendant group close to the backbone, separated only by a methylene spacer. This synthetic design likely facilitates hydrated counterions to accumulate around the polar phosphonate groups, close to the doped backbone where they can easily compensate the charge carriers formed upon oxidation., A.L., D.L.O., and D.M. would like to acknowledge the Australian Research Council, Discovery Project Grant DP190102560, for funding this research. The authors would like to acknowledge the use of facilities and the assistance of Dr. David Miskovic of the UNSW School of Materials Science and Engineering, Dr. Anne Rich of the Spectroscopy Laboratory, Dr. Bill Bin Gong and Dr. Yu Wang in the Solid State & Elemental Analysis Unit, as well as the members of the NMR Facility under the Mark Wainwright Analytical Centre at UNSW Sydney., Peer Reviewed, Postprint (published version)

David Gillespie,1,2 Nick Francis,3 Haroon Ahmed,4 Kerenza Hood,2 Carl Llor,5 Patrick White,6 Emma Thomas-Jones,2 Helen Stanton,2 Bernadette Sewell,7 Rhiannon Phillips,8 Gurudutt Naik,4 Hasse Melbye,9 Rachel Lowe,2 Nigel Kirby,2 Ann Cochrane,10 Janine Bates,2 Mohammed Fasihul Alam,11 Christopher Butler1 1Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, England, UK; 2Centre for Trials Research, School of Medicine, College of Biomedical & Life Sciences, Cardiff University, Cardiff, Wales, UK; 3Primary Care, Population Sciences and Medical Education, University of Southampton, Southampton, England, UK; 4Division of Population Medicine, School of Medicine, Cardiff University, Cardiff, Wales, UK; 5University Institute in Primary Care Research Jordi Gol, Via Roma Health Centre, Barcelona, Spain; 6School of Population Health and Environmental Sciences, Kings College London, London, England, UK; 7Swansea Centre for Health Economics, Swansea University, Swansea, Wales, UK; 8Cardiff School of Sport & Health Science, Cardiff Metropolitan University, Cardiff, Wales, UK; 9General Practice Research Unit, Department of Community Medicine, UIT the Arctic University of Norway, Tromsø, Norway; 10York Trials Unit, Department of Health Sciences, University of York, York, England, UK; 11Department of Public Health, College of Health Sciences, QU-Health, Qatar University, Doha, QatarCorrespondence: David Gillespie, Nuffield Department of Primary Care Health Sciences, University of Oxford, Radcliffe Observatory Quarter, Woodstock Road, Oxford, England, OX2 6GG, UK, Email david.gillespie@phc.ox.ac.ukBackground: It has been demonstrated that antibiotic prescribing for Acute Exacerbations of Chronic Obstructive Pulmonary Disease (AECOPD) can be safely reduced in primary care when general practitioners have access to C-reactive protein (CRP) rapid testing.Aim: To investigate the factors associated with post-consultation COPD health status in patients

BACKGROUND: C-reactive protein (CRP) point-of-care testing can reduce antibiotic use in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in primary care, without compromising patient care. Further safe reductions may be possible. AIM: To investigate the associations between presenting features and antibiotic prescribing in patients with AECOPD in primary care. DESIGN AND SETTING: Secondary analysis of a randomised controlled trial of participants presenting with AECOPD in primary care (the PACE trial). METHOD: Clinicians collected participants' demographic features, comorbid illnesses, clinical signs, and symptoms. Antibiotic prescribing decisions were made after participants were randomised to receive a point-of-care CRP measurement or usual care. Multivariable regression models were fitted to explore the association between patient and clinical features and antibiotic prescribing, and extended to further explore any interactions with CRP measurement category (CRP not measured, CRP <20 mg/l, or CRP ≥20 mg/l). RESULTS: A total of 649 participants from 86 general practices across England and Wales were included. Odds of antibiotic prescribing were higher in the presence of clinician-recorded crackles (adjusted odds ratio [AOR] = 5.22, 95% confidence interval [CI] = 3.24 to 8.41), wheeze (AOR = 1.64, 95% CI = 1.07 to 2.52), diminished vesicular breathing (AOR = 2.95, 95% CI = 1.70 to 5.10), or clinician-reported evidence of consolidation (AOR = 34.40, 95% CI = 2.84 to 417.27). Increased age was associated with lower odds of antibiotic prescribing (AOR per additional year increase = 0.98, 95% CI = 0.95 to 1.00), as was the presence of heart failure (AOR = 0.32, 95% CI = 0.12 to 0.85). CONCLUSION: Several demographic features and clinical signs and symptoms are associated with antibiotic prescribing in AECOPD. Diagnostic and prognostic value of these features may help identify further safe reductions.

We demonstrate the use of tetraethylorthosilicate (TEOS) as a silica precursor for water barrier poly(styrenebutadiene) latex dispersion coating applications. The TEOS is adsorbed at the surface interface by the latex particles in the aqueous dispersion due to the hydrophobic nature of the surface and the TEOS. It then undergoes hydrolysis and condensation to the silica phase in the interstitial sites in the partially dry close-packed polymer structure. The fully cured film exhibits a greater degree of coalescence than films prepared from the unmodified latex binder. Large discrete silica particles are not formed within the cured film; rather the films contain homogenous silica dispersion with a probable particle size no larger than 10 nm. This higher degree of coalescence results in improvements in water vapour barrier performance from 121 - 20 g m(-2) d(-1), with direct water barrier performance (Cobb 120 s) improving from 25 to < 2 g m(-2), compared to the silica-free film.

We demonstrate how nano-scale metamorphic processes can be unravelled with small- and wide-angle transmission scattering of Synchrotron radiation (SAXS and WAXS, respectively) in concert with a novel loading cell. We studied the dehydration of Volterra alabaster, a polycrystalline gypsum rock, at four temperatures (128, 144, 152, and 173˚C) and two axial strains. Cylindrical samples with a diameter of 13 mm and a thickness of 1 mm were confined axially by the Beryllium (Be) windows of the loading cell. Prior to heating, the Be windows were screwed into the cell up to hand-tightness ("low strain") or up to 54 Nm ("high strain") using a torque wrench, thus keeping the sample discs in place. Radially, the discs remained unconfined with respect to the cell interior. A high-powered electric heater clamped around the cell supplied heat conductively. Numerical models of the thermo-elastic response of the cell and the sample suggest that dehydration onset occurred at temperatures above 105 ˚C. Hence, the transient heating period of the sample was so short compared to the observed dehydration kinetics that the experiments were essentially isothermal. During each experiment, three or five 100x100 micron interrogation points along the disc radius were irradiated with Synchrotron radiation (12 or 16 KeV) for 5 s per scan. These points were distributed equidistantly between disc centre and margin. WAXS and SAXS detectors collected patterns over a scattering vector length range between 1.17 to 4.13 per Å and 0.003 to 0.22 per Å, respectively. The dehydration product was always hemihydrate. The WAXS data provide the dehydration kinetics. The conversion curves are well described by an Avrami model. However, at the two intermediate temperatures of the low-strain experiments, a clear transient "bump" in the conversion curves suggests a switch in mechanism, possibly from nucleation-and-growth to diffusion control. An Arrhenius fit to low- and high-strain data yields activation energie