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Constantinos Kallis,1– 3 Amit Kaura,1,3 Nathan A Samuel,4 Abdulrahim Mulla,3 Ben Glampson,3 Kevin O’Gallagher,5 Jim Davies,4 Dimitri Papadimitriou,3 Kerrie J Woods,4 Anoop D Shah,6,7 Bryan Williams,6,7 Folkert W Asselbergs,6,7 Erik K Mayer,3,8 Richard W Lee,1,9 Christopher Herbert,10 Stuart W Grant,11 Nick Curzen,12 Iain B Squire,13 Thomas Johnson,14 Ajay M Shah,15 Divaka Perera,5 Rajesh K Kharbanda,4 Riyaz S Patel,6 Keith M Channon,4 Jamil Mayet,1,3 Jennifer K Quint1– 3 1National Heart and Lung Institute, Imperial College London, London, UK; 2School of Public Health, Imperial College London, London, UK; 3NIHR Imperial Biomedical Research Centre, Imperial College London and Imperial College Healthcare NHS Trust, London, UK; 4NIHR Oxford Biomedical Research Centre, University of Oxford and Oxford University Hospitals NHS Foundation Trust, Oxford, UK; 5NIHR King’s Biomedical Research Centre, King’s College London and King’s College Hospital NHS Foundation Trust, London, UK; 6NIHR University College London Biomedical Research Centre, University College London and University College London Hospitals NHS Foundation Trust, London, UK; 7Institute of Health Informatics, University College London, London, UK; 8Imperial Clinical Analytics, Research & Evaluation (iCARE) and Department of Surgery & Cancer, Imperial College London, London, UK; 9Early Diagnosis and Detection Centre, NIHR BRC at The Royal Marsden and Institute of Cancer Research, London, UK; 10NIHR Leeds Clinical Research Facility, Leeds Teaching Hospitals Trust and University of Leeds, Leeds, UK; 11NIHR Manchester Biomedical Research Centre, Manchester University NHS Foundation Trust and the University of Manchester, Manchester, UK; 12NIHR Southampton Clinical Research Facility and Biomedical Research Centre, Faculty of Medicine, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK; 13NIHR Leicester Biomedical Research Centre, Glenfield Hospital, and Department of Cardiovascular Sciences, University of Leicester, Leicester, UK; 14NIHR Bristol Biomedical Research Centre, University of Bristol and University Hospitals Bristol NHS Foundation Trust, Bristol, UK; 15NIHR Guys & St Thomas’ Hospital Clinical Research Facility, King’s College Hospital, and King’s College London British Heart Foundation Centre of Excellence, London, UKCorrespondence: Jennifer K Quint, School of Public Health, Imperial College London, Floor 9, Sir Michael Uren Building, 86 Wood Ln, London, W12 0BZ, United Kingdom, Email j.quint@imperial.ac.ukBackground: No single biomarker currently risk stratifies chronic obstructive pulmonary disease (COPD) patients at the time of an exacerbation, though previous studies have suggested that patients with elevated troponin at exacerbation have worse outcomes. This study evaluated the relationship between peak cardiac troponin and subsequent major adverse cardiac events (MACE) including all-cause mortality and COPD hospital readmission, among patients admitted with COPD exacerbation.Methods: Data from five cross-regional hospitals in England were analysed using the National Institute of Health Research Health Informatics Collaborative (NIHR-HIC) acute coronary syndrome database (2008– 2017). People hospitalised with a COPD exacerbation were included, and peak troponin levels were standardised relative to the 99th percentile (upper limit of normal). We used Cox Proportional Hazard models adjusting for age, sex, laboratory results and clinical risk factors, and implemented logarithmic transformation (base-10 logarithm). The primary outcome was risk of MACE within 90 days from peak troponin measurement. Secondary outcome was risk of COPD readmission within 90 days from peak troponin measurement.Results: There were 2487 patients included. Of these, 377 (15.2%) patients had a MACE event and 203 (8.2%) were readmitted within 90 days from peak troponin measurement. A total of 1107 (44.5%) patients had an elevated troponin level. Of 1107 patients with elevated troponin at exacerbation, 256 (22.8%) had a MACE event and 101 (9.0%) a COPD readmission within 90 days from peak troponin measurement. Patients with troponin above the upper limit of normal had a higher risk of MACE (adjusted HR 2.20, 95% CI 1.75– 2.77) and COPD hospital readmission (adjusted HR 1.37, 95% CI 1.02– 1.83) when compared with patients without elevated troponin.Conclusion: An elevated troponin level at the time of COPD exacerbation may be a useful tool for predicting MACE in COPD patients. The relationship between degree of troponin elevation and risk of future events is complex and requires further investigation.Keywords: COPD, CVD, exacerbation

Raman and photoluminescence analyses were carried out on silicon quantum wires with 5- to 10-nanometer diameter range and a 0.5-micrometer length. The wires were observed to react to weakly disordered structures and exhibited stress and confinement effects. They were also found to emit photoluminescence ranging from 500 to 600 nanometers. The wavelength and the polarization state of the initial laser beam were believed to dictate the energy position and photoluminescence efficiency.

We report on the application of a static (dc) electric field in the plume region during the pulsed Nd doped yttrium aluminum garnet laser deposition (PLD) of tetrahedral amorphous carbon (ta-C) films in vacuum ambient (pressure=10-4–10-3 Pa), where the working pressure is exclusively due to ablation vapor. This approach is strikingly different from the plasma- or ion-beam-assisted PLD because the mean free path at this pressure is by far longer than the target to substrate distance. Thus, the electric field interacts with individual ionized species invoking ion acceleration and gas-phase reactions among different ionized species. These phenomena are clearly dependent on the laser wavelength (first, second, or third harmonic, λ=1064, 532, and 355 nm, respectively) used for the ablation. We found that the application of the electric field causes surface smoothing (the roughness decreases from about 1 to 0.4 nm) and faster deposition rate (from about 2 to 7 nm/min) for the second and third harmonics. In addition, the phenomena are less intense in the case of the first harmonic due to the low concentration of ionized species in the plume. In addition, in the case of PLD using λ=532 nm, the electric field improves the film’s density (from 2.60 to 2.95 g/cm3). The correlations found are discussed in terms of the ablated species and the deposition mechanisms of the ta-C. [ABSTRACT FROM AUTHOR]

The structural properties of copper selenide (CuxSe), formed as a secondary phase on the surface of CuGaSe2 films grown under Cu-rich conditions on GaAs (100) substrates, were studied by micro-Raman spectroscopy. Raman bands at 45 and 263 cm-1, observed on crystallites dispersed on the CuGaSe2 film, are in agreement with the Raman modes of CuSe and Cu2Se. Polarization- and angular-dependent micro-Raman measurements reveal that the CuxSe-crystallites are grown with a preferential orientation on the CuGaSe2 surface. [ABSTRACT FROM AUTHOR]

Raman scattering and photoluminescence (PL) emission of Cu[sub x]Ga[sub y]Se[sub 2] thin films, grown by metalorganic chemical vapor deposition (MOCVD) on GaAs (100) and by physical vapor deposition (PVD) on Glass/Mo substrates, were studied at room and low temperatures as a function of composition. Line width changes of Raman bands in the temperature range 20–300 K indicate the formation of a more disordered Cu[sub x]Ga[sub y]Se[sub 2] phase with increasing Ga content. It is most likely that Raman bands observed at 193 and 199 cm-1 in the Ga-rich samples at low temperatures are associated with defect-related interface modes. The intensity increase of these bands and the photoluminescence intensity enhancement may be correlated to an increase in defect concentration in the Ga-rich phase. The radiative recombination in defect-rich Ga-rich samples with a higher degree of disorder apparently supports the PL emission. The observed changes are more pronounced in MOCVD than in PVD grown films. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The structural and optical properties of nitrogenated amorphous carbon films, grown by rf-magnetron sputtering on silicon substrates, were studied by Raman and photoluminescence (PL) spectroscopy as a function of the nitrogen concentration and the substrate bias voltage V[sub b]. For films deposited with V[sub b]=10 V, the photoluminescence emission was most intense at nitrogen concentrations in the carrier gas of 25% (75% Ar), while the intensity ratio I(D)/I(G) of the Raman bands of disordered graphite (D band) and graphite (G band) partially substituted by nitrogen exhibited a minimum simultaneously observed with a minimum of G-band frequency and a maximum of G-band width. Changes in spectral characteristics of Raman scattering at a concentration of 25% (≅30 at %) are indicative of an increase of sp³-bonded fraction and disorder. PL-enhancement coincides, in this case, with structural changes and is probably correlated to the substitution of nitrogen in the tetrahedraly bonded amorphous matrix. In the case of films deposited in a pure nitrogen atmosphere, N[sub 2] = 100%, no significant PL-intensity changes appeared to exist between films deposited at low positive (10 V) and highly negative (-200 V) substrate bias. After several months of sample storage in air, samples grown at negative V[sub b] were found to preserve their structural and optical properties, while films grown at positive bias (V[sub b]=10) and nitrogen concentrations in the carrier gas above 70% (≅40 at %) delaminated. [ABSTRACT FROM AUTHOR]

Raman scattering photoluminescence (PL) emission of Cu(sub x)Ga(sub y)Se(sub 2) thin films, are studied at room or low temperatures as a function of composition. An increase in defect concentration and an intensity enhancement of defect related PL emission, coincides with the increase in intensity of the modes.

Vibrational relaxation of HCl(v=1) has been measured in mixtures with H2, HD, and D2 in the temperature range between 300 and 140 K using laser-induced fluorescence. Relaxation in mixtures with n-H2 and with hydrogen enriched with its para modification is a pure vibration–translation, rotation (V–T,R) process. In mixtures with HD and D2 both vibration–vibration (V–V) and V–T,R relaxation rates could be determined separately. [ABSTRACT FROM AUTHOR]

Drawing on Aaker’s brand equity model and Keller’s brand engagement concept and building on the sponsorship between a professional basketball club and a software company, this study examined how sport sponsorship affects brand equity and purchase behavior of the sponsor’s product. Data from 222 survey respondents were collected and analyzed using structural equation modeling techniques. The results provided evidence that perceived quality and brand engagement impact brand loyalty and purchase behavior of fans toward the sponsor’s product. Perceived fit between sponsor and sponsee and team identification were found to influence significantly sponsor’s brand equity constructs. The study extends Aaker’s model in the sport sponsorship context and highlights the influential role of perceived quality and brand engagement on driving sport team fans to form brand loyalty and purchase sponsor’s product. [ABSTRACT FROM PUBLISHER]

What is known and objective The relative effectiveness and safety profile of the treatments with marketing authorization for relapsing multiple sclerosis ( MS) are not well known because randomized controlled trials with head-to-head comparisons between these treatments do not exist. Thus, a network of multiple-treatments meta-analysis was performed using four clinical outcomes: 'patients free of relapse', 'patients without disease progression', 'patients without MRI progression' and 'patients with adverse events'. Methods Randomized controlled trials ( RCTs) on MS were systematically searched in PubMed and Cochrane Central Register of Controlled Trial. The network analysis performed pairwise comparisons between the marketed treatments (Betaferon 250mcg, Avonex 30mcg, Rebif 44mcg, Rebif 22mcg, Aubagio 7 mg, Aubagio 14 mg, Copaxone 20 mg, Tysabri 300 mg, Gilenya 0·5 mg and Novantrone 12 mg/m2) using direct and indirect analyses. Results and discussion The analysis included 48 articles, involving 20 455 patients with MS. The direct analysis showed better response for more than one outcome for Gilenya compared with Avonex ('patients free of relapse' and 'patients without MRI progression') and for Betaferon compared with Avonex ('patients without disease progression' and 'patients without MRI progression'). The indirect analysis indicated that Tysabri may have better relative effectiveness compared with the other treatments for two outcomes: 'patients free of relapse' and 'patients without MRI progression'. Regarding 'patients with adverse events', no data were available for all comparisons to make fair inferences. What is new and conclusion This was an attempt, for the first time, to compare the efficacy and safety profile of existing approved treatments for relapsing MS. Although some treatments have shown better response, the results of the network analysis should be interpreted with caution because of the lack of RCTs with head-to-head comparisons between treatments. [ABSTRACT FROM AUTHOR]

Objective To assess the interaction of the MTHFR C677T polymorphism with changes in lipid and glucose metabolism effected by oral hormone replacement therapy (HRT) in postmenopausal women. Methods In this open-label, prospective, interventional study, parameters of lipid and glucose metabolism, as well as homocysteine, were assessed in 97 postmenopausal women at baseline and 1 year after the initiation of HRT. Participants were stratified into three subgroups, according to the MTHFR C677T polymorphism (wild-type: CC genotype; heterozygous: CT genotype; homozygous for the mutant variable: TT genotype). Results The TT genotype was associated with an elevation of total and low density lipoprotein (LDL) cholesterol, while CT and CC genotypes were associated with a reduction of total cholesterol and LDL cholesterol after 1 year of HRT ( p = 0.032 for total cholesterol and p = 0.002 for LDL cholesterol). Women with the TT genotype had higher glucose levels in contrast to women with the CC genotype who had lower glucose levels after 1 year of HRT ( p = 0.011). Additionally, CC carriers under HRT had a significant elevation of apolipoprotein A1 levels ( p = 0.018), contrarily to CT and TT genotypes. Conclusion While HRT was associated with favorable changes in lipid and metabolic parameters in carriers of the CC genotype, this effect was not evident in carriers of the T allele. The MTHFR C677T polymorphism may modify the effect of HRT on lipid and metabolic parameters in postmenopausal women. [ABSTRACT FROM AUTHOR]

In fluid mechanics, topology optimization is used for designing flow passages, connecting predefined inlets and outlets, with optimal performance based on selected criteria. In this article, the continuous adjoint approach to topology optimization in incompressible ducted flows with heat transfer is presented. A variable porosity field, to be determined during the optimization, is the means to define the optimal topology. The objective functions take into account viscous losses and the amount of heat transfer. Turbulent flows are handled using the Spalart–Allmaras model and the proposed adjoint is exact,i.e.the adjoint to the turbulence model equation is formulated and solved, too. This is an important novelty in this article which extends the porosity-based method to account for heat transfer flow problems in turbulent flows. In problems such as the design of manifolds, constraints on the outlet flow direction, rates and mean outlet temperatures are imposed. [ABSTRACT FROM AUTHOR]

SUMMARY Robust design problems in aerodynamics are associated with the design variables, which control the shape of an aerodynamic body, and also with the so-called environmental variables, which account for uncertainties. In this kind of problems, the set of design variables, which leads to optimal performance, taking into account possible variations in the environmental variables, is sought. One of the possible ways to solve this problem is by means of the second-order second-moment approach, which requires first-order and second-order derivatives of the objective function with respect to the environmental variables. Should the minimization problem be solved using a gradient-based method, algorithms for the computation of up to third-order sensitivity derivatives (twice with respect to the environmental variables and once with respect to the shape controlling design variables) must be devised. In this paper, a combination of the continuous adjoint variable method and direct differentiation to compute the third-order sensitivities is proposed. This is shown to be the most efficient among all alternative methods provided that the environmental variables are much less than the design ones. Apart from presenting the method formulation, this paper focuses on the assessment of the so-computed up-to third-order mixed derivatives through comparison with costly finite-difference schemes. To this end, the robust design of a two-dimensional duct is performed. Then, using the validated method, the robust design of a two-dimensional cascade airfoil is demonstrated. Although both cases are handled as inverse design problems, the method can be extended to other objective functions or three-dimensional problems in a straightforward manner. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]