3,153 research outputs found

    Tuning the crystallinity parameters in macroporous titania films

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    Although macroporous titania scaffolds are used for many different applications, not much is known about the importance of the synthesis strategy on the resulting materials' properties. We present a comparative study on the influence of different colloidal titania precursors for direct co-deposition with poly(methyl methacrylate) (PMMA) beads on the properties of the resulting macroporous scaffolds after calcination. The colloidal titania precursors for the film assembly differ in their size and initial crystallinity, ranging from amorphous sol-gel clusters to already crystalline pre-formed particles of 4 nm, 6 nm and 20 nm in size, as well as a combination of sol-gel and nanoparticle precursors in the so-called `Brick and Mortar' approach. The type of the precursor greatly influences the morphology, texture and the specific crystallinity parameters of the macroporous titania scaffolds after calcination such as the size of the crystalline domains, packing density of the crystallites in the macroporous walls and interconnectivity between the crystals. Moreover, the texture and the crystallinity of the films can be tuned by postsynthesis processing of the films such as calcination at different temperatures, which can be also preceded by a hydrothermal treatment. The ability to adjust the porosity, the total surface area and the crystallinity parameters of the crystalline macroporous films by selecting suitable precursors and by applying different post-synthetic treatments provides useful tools to optimize the film properties for different applications

    Statewide retrospective study of low acuity emergency presentations in New South Wales, Australia: who, what, where and why?

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    This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/Abstract Objective The present study aims to use a statewide population-based registry to assess the prevalence of low acuity emergency department (ED) presentations, describe the trend in presentation rates and to determine whether they were associated with various presentation characteristics such as the type of hospital as well as clinical and demographic variables. Design and setting This was a retrospective analysis of a population-based registry of ED presentations in New South Wales (NSW). Generalised estimating equations with log links were used to determine factors associated with low acuity presentations to account for repeat presentations and the possibility of clustering of outcomes. Participants Patients were included in this analysis if they presented to an ED between January 2010 and December 2014. The outcomes of interest were low acuity presentation, defined as those who self-presented (were not transported by ambulance), were assigned a triage category of 4 or 5 (semiurgent or non-urgent) and discharged back to usual residence from ED. Results There were 10.7 million ED presentations analysed. Of these, 45% were classified as a low acuity presentation. There was no discernible increase in the rate of low acuity presentations across NSW between 2010 and 2014. The strongest predictors of low acuity ED presentation were age <40 years of age (OR 1.77); injury or musculoskeletal administrative and non-urgent procedures (OR 2.96); ear, nose and throat, eye or oral (OR 5.53); skin or allergy-type presenting problems (OR 2.84). Conclusions Low acuity ED presentations comprise almost half of all ED presentations. Alternative emergency models of care may help meet the needs of these patients

    Prognostic Role of Polyvascular Involvement in Patients with Symptomatic Peripheral Artery Disease.

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    Background: Statin therapy is recommended for patients with peripheral artery disease (PAD). However, PAD patients with polyvascular (PV) extent remain threatened by an increased residual cardiovascular (CV) risk. Purpose: To investigate the association of prescribed statin therapy and mortality in PAD patients with or without PV extent. Methods: A single-center retrospective longitudinal observational study originating from a consecutive registry with 1380 symptomatic PAD patients over a mean observational time of 60 ± 32 months. The association of atherosclerotic extent and statin use (PAD, plus one additional region (CAD or CeVD, [+1 V]), +2 vascular regions (+CAD and CeVD [+2 V]) with the risk of all-cause mortality was evaluated using Cox proportional hazard models adjusted for potential confounding factors. Results: The mean age of the study's participants was 72.0 ± 11.7 years, with 36% being female. PAD patients with PV extent [+1 V] and [+2 V] were older and suffered from diabetes, hypertension, or dyslipidemia more often; they, too, had more severely impaired kidney function (all p < 0.0001) compared to patients with PAD only. PAD patients with PV [+1 V] and [+2 V] received better statin medication and reached the recommended LDL-C target compared to PAD-only patients (p < 0.001). Despite better statin treatment, the rate of all-cause mortality was higher in PV patients than in PAD-only patients (PAD only: 13%; [+1 V]: 22%; [+2 V]: 35%; p < 0.0001). Conclusion: PV patients receive better statin therapy than PAD-only patients but nevertheless still have higher mortality rates. Future studies are needed to explore whether more aggressive LDL-lowering treatment for PAD patients may be translated into better prognosis

    Modulated IR radiometry as a tool for the thickness control of coatings

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    The thickness of coatings can be determined using the data measured by Modulated IR Radiometry for sets of coatings, produced under specific controlled conditions: – Keeping constant all deposition parameters except the deposition time, coatings of approximately constant thermal transport properties, but different thickness are produced. The modulated IR phase lag signals measured for the coatings are calibrated with the help of signals obtained for homogeneous opaque reference samples of smooth surface. Quantitative results for the thermal transport properties are obtained using the inverse solution of the 2-layer thermal wave problem by which direct relations are established between the relative extrema of the inverse calibrated thermal wave phase signals measured as a function of the heating modulation frequency and the thermal coating parameters, the ratio of the effusivities coating-to-substrate, the coating's thermal diffusion time, and the coating thickness. The coating thickness values obtained by Modulated IR Radiometry are compared with the values measured by standard microscopic methods, and relative errors of 3 – 4% have been found for the coating thickness of a set of TiCO coatings on steel, presented here as an example.(undefined

    The Sydney Triage to Admission Risk Tool (START) to predict Emergency Department Disposition: A derivation and internal validation study using retrospective state-wide data from New South Wales, Australia.

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    BACKGROUND: Disposition decisions are critical to the functioning of Emergency Departments. The objectives of the present study were to derive and internally validate a prediction model for inpatient admission from the Emergency Department to assist with triage, patient flow and clinical decision making. METHODS: This was a retrospective analysis of State-wide Emergency Department data in New South Wales, Australia. Adult patients (age ≥ 16 years) were included if they presented to a Level five or six (tertiary level) Emergency Department in New South Wales, Australia between 2013 and 2014. The outcome of interest was in-patient admission from the Emergency Department. This included all admissions to short stay and medical assessment units and being transferred out to another hospital. Analyses were performed using logistic regression. Discrimination was assessed using area under curve and derived risk scores were plotted to assess calibration. RESULTS: 1,721,294 presentations from twenty three Level five or six hospitals were analysed. Of these 49.38% were male and the mean (sd) age was 49.85 years (22.13). Level 6 hospitals accounted for 47.70% of cases and 40.74% of cases were classified as an in-patient admission based on their mode of separation. The final multivariable model including age, arrival by ambulance, triage category, previous admission and presenting problem had an AUC of 0.82 (95% CI 0.81, 0.82). CONCLUSION: By deriving and internally validating a risk score model to predict the need for in-patient admission based on basic demographic and triage characteristics, patient flow in ED, clinical decision making and overall quality of care may be improved. Further studies are now required to establish clinical effectiveness of this risk score model

    Laser modulated optical reflectance of thin semiconductor films on glass

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    Semiconductor films, deposited by reactive magnetron sputtering on glass substrates have been analyzed with the help of laser-modulated optical reflectance. The results are discussed with respect to the thermal and charge carrier transport properties. Semiconductor properties have been identified both for micro-crystalline and amorphous film

    The Fermi energy in oxides: assessing and understanding the limits using XPS

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    The Fermi energy in semiconductors can often be freely controlled across the whole energy gap by doping. This is not the case in oxides, where different mechanisms exist, which can limit the range of the Fermi energy. These limits can be caused by i) dopants having deep rather than shallow charge transition levels, ii) self-com­pen­sation where the Fermi energy dependence of the defect formation energy leads to spontaneous formation of compensating defects, iii) the change of the oxidation state of either the cations or the oxygen. The latter is particularly relevant for compounds with transition metal or rare earth cations and has been recently demonstrated to explain the low water splitting efficiency of hematite [1]. Please click Additional Files below to see the full abstract
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