1,121 research outputs found

    Modeling the effects of concentration of solid nanoparticles in liquid feedstock injection on high-velocity suspension flame spray process

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    This paper presents the effects of the concentration of solid nanoparticles in the liquid feedstock injection on the high-velocity suspension flame spray (HVSFS) process. Four different concentrations of solid nanoparticles in suspension droplets with various droplet diameters are used to study gas dynamics, vaporization rate, and secondary breakup. Two types of injections, viz. surface and group, are used. The group-type injection increases the efficiency of droplet disintegration and the evaporation process and reduces the gas cooling. The initiation of the fragmentation process is difficult for small droplets carrying a high concentration of nanoparticles. Also, smaller droplets undergo rapid vaporization, leaving clogs of nanoparticles in the middle of the barrel. For larger droplets, severe fragmentation occurs inside the combustion chamber. For a higher concentration of nanoparticles, droplets exit the gun without complete evaporation. The results suggest that, in coating applications involving a higher concentration of nanoparticles, smaller droplet sizes are preferred

    Prediction of cardiac worsening through to cardiogenic shock in patients with acute heart failure

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    Aims: Acute heart failure (AHF) can result in worsening of heart failure (WHF), cardiogenic shock (CS), or death. Risk factors for these adverse outcomes are not well characterized. This study aimed to identify predictors for WHF or new‐onset CS in patients hospitalized for AHF. Methods and results: Prospective cohort study enrolling consecutive patients with AHF admitted to a large tertiary care centre with follow‐up until death or discharge. WHF was defined by the RELAX‐AHF‐2 criteria. CS was defined as SCAI stages B–E. Potential predictors were assessed by fitting logistic regression models adjusted for age and sex. N = 233 patients were enrolled, median age was 78 years, and 80 were women (35.9%). Ischaemic cardiomyopathy was present in 82 patients (40.8%). Overall, 96 (44.2%) developed WHF and 18 (9.7%) CS. In‐hospital death (8/223, 3.6%) was related to both events (WHF: OR 6.64, 95% CI 1.21–36.55, P = 0.03; CS: OR 38.27, 95% CI 6.32–231.81, P < 0.001). Chronic kidney disease (OR 2.20, 95% CI 1.25–3.93, P = 0.007), logarithmized serum creatinine (OR 2.90, 95% CI 1.51–5.82, P = 0.002), cystatin c (OR 1.86, 95% CI 1.27–2.77, P = 0.002), tricuspid valve regurgitation (OR 2.08, 95% CI 1.11–3.94, P = 0.023) and logarithmized pro‐adrenomedullin (OR 3.01, 95% CI 1.75–5.38, P < 0.001) were significant predictors of WHF. Chronic kidney disease (OR 3.17, 95% CI 1.16–9.58, P = 0.03), cystatin c (OR 1.88, 95% CI 1.00–3.53, P = 0.045), logarithmized pro‐adrenomedullin (OR 2.90, 95% CI 1.19–7.19, P = 0.019), and tricuspid valve regurgitation (OR 10.44, 95% CI 2.61–70.00, P = 0.003) were significantly with new‐onset CS. Conclusions: Half of patients admitted with AHF experience WHF or new‐onset CS. Chronic kidney disease, tricuspid valve regurgitation, and elevated pro‐adrenomedullin concentrations predict these events. They could potentially serve as early warning signs for further deterioration in AHF patients

    Adherence to subcutaneous interferon beta-1a treatment using an electronic injection device:a prospective open-label Scandinavian noninterventional study (the ScanSmart study)

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    Background: Disease modifying drugs help control the course of relapsing remitting multiple sclerosis (RRMS); however, good adherence is needed for long-term outcomes. Objective: To evaluate patient adherence to treatment with subcutaneous interferon beta-1a using RebiSmart® and assess injection-site reactions and treatment satisfaction. Methods: This prospective, single-arm, open-label, noninterventional multicenter Phase IV trial included disease modifying drug-experienced mobile patients with RRMS. Adherence was measured over 12 weeks. Items 13–23, 35, 37, and 38 of the Multiple Sclerosis Treatment Concerns Questionnaire (injection-site reactions and treatment satisfaction) were recorded at 12 weeks. Results: Sixty patients were recruited (mean age 43.7 [±SD 7.9] years; 83% female; mean years since multiple sclerosis diagnosis 6.7 [SD 4.5]). Adherence data were obtained in 54 patients only due to technical problems with six devices. Over 12 weeks, 89% (n=48) of patients had ≥90% adherence to treatment. Most patients experienced mild influenza-like symptoms and injection-site reactions, and global side effects were minimal. Most patients (78%) rated the convenience as the most important aspect of the device, and most experienced no or mild pain. Conclusion: RRMS patients treated with subcutaneous interferon beta-1a, administered with RebiSmart, demonstrated generally good adherence, and the treatment was generally well tolerated

    Surface Screening Charge and Effective Charge

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    The charge on an atom at a metallic surface in an electric field is defined as the field-derivative of the force on the atom, and this is consistent with definitions of effective charge and screening charge. This charge can be found from the shift in the potential outside the surface when the atoms are moved. This is used to study forces and screening on surface atoms of Ag(001) c(2×2)(2\times 2) -- Xe as a function of external field. It is found that at low positive (outward) fields, the Xe with a negative effective charge of -0.093 e|{e}| is pushed into the surface. At a field of 2.3 V \AA1^{-1} the charge changes sign, and for fields greater than 4.1 V \AA1^{-1} the Xe experiences an outward force. Field desorption and the Eigler switch are discussed in terms of these results.Comment: 4 pages, 1 figure, RevTex (accepted by PRL

    Navigating overgrazing and cultural values through narratives and participatory mapping : a socio-cultural analysis of sheep grazing in the Faroe Islands

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    Long-term livestock grazing has shaped landscapes, biodiversity, societies, cultures, and economies in the North Atlantic over time. However, overgrazing has become a major environmental sustainability challenge for this region, covering the Faroe Islands, Greenland, Iceland, Norway, and Scotland. The objective of this study was to elicit narratives and spatial patterns of local people's management preferences for sheep grazing in the Faroe Islands through a socio-cultural lens. We collected data via a Public Participation Geographic Information Systems (PPGIS) survey with an open question about hopes and concerns for sheep management in the Faroe Islands and a mapping exercise for expressing spatial preferences for sheep management. Four distinct narratives emerged from a qualitative analysis of responses to the open question (n = 184): (1) Sustainable sheep management, (2) Nature without sheep, (3) Sheep as part of Faroese culture, and (4) Sheep as nuisance. Visual inspection of narrative-specific maps with locations where either no or fewer sheep were preferred indicated that sheep management is not simply a 'sheep vs. no sheep' issue but embedded in a more nuanced consideration of the place of sheep in the landscape and society. For example, for some residents sheep-farming is not a commercial enterprise but a social activity and local source of food. Our combined methodological approach using qualitative and spatial data can help researchers in other fields identify the interplay between place-specific areas of grazing management concern and socio-cultural values, enabling more targeted land-use management policies or plans.Peer reviewe

    The Association of Type 2 Diabetes Mellitus with Cerebral Gray Matter Volume Is Independent of Retinal Vascular Architecture and Retinopathy.

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    It is uncertain whether small vessel disease underlies the relationship between Type 2 Diabetes Mellitus (T2DM) and brain atrophy. We aimed to study whether retinal vascular architecture, as a proxy for cerebral small vessel disease, may modify or mediate the associations of T2DM with brain volumes. In this cross-sectional study using Magnetic Resonance Imaging (MRI) scans and retinal photographs in 451 people with and without T2DM, we measured brain volumes, geometric measures of retinal vascular architecture, clinical retinopathy, and MRI cerebrovascular lesions. There were 270 people with (mean age 67.3 years) and 181 without T2DM (mean age 72.9 years). T2DM was associated with lower gray matter volume (p = 0.008). T2DM was associated with greater arteriolar diameter (p = 0.03) and optimality ratio (p = 0.04), but these associations were attenuated by adjustments for age and sex. Only optimality ratio was associated with lower gray matter volume (p = 0.03). The inclusion of retinal measures in regression models did not attenuate the association of T2DM with gray matter volume. The association of T2DM with lower gray matter volume was independent of retinal vascular architecture and clinical retinopathy. Retinal vascular measures or retinopathy may not be sufficiently sensitive to confirm a microvascular basis for T2DM-related brain atrophy

    Microscopic Surface Structure of Liquid Alkali Metals

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    We report an x-ray scattering study of the microscopic structure of the surface of a liquid alkali metal. The bulk liquid structure factor of the eutectic K67Na33 alloy is characteristic of an ideal mixture, and so shares the properties of an elemental liquid alkali metal. Analysis of off-specular diffuse scattering and specular x-ray reflectivity shows that the surface roughness of the K-Na alloy follows simple capillary wave behavior with a surface structure factor indicative of surface induced layering. Comparison of thelow-angle tail of the K67Na33 surface structure factor with the one measured for liquid Ga and In previously suggests that layering is less pronounced in alkali metals. Controlled exposure of the liquid to H2 and O2 gas does not affect the surface structure, indicating that oxide and hydride are not stable at the liquid surface under these experimental conditions.Comment: 12 pages, 3 figures, published in Phys. Rev.
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