42 research outputs found
Growth and Mechanical and Tribological Characterization of Multi-Layer Hard Carbon Films
Vacuum-arc deposition is used to deposit multilayer C films by modulating the sample bias during deposition. Effect of varying the sublayer thickness in multilayer films consisting of alternating layers of ``hard`` (68.4 GPa, -100 V bias) and ``soft`` (27.5 GPa, - 200 V bias) was investigated. Films consisting of equal thickness layers of hard and soft material and an individual layer thickness varying from 10 to 35 nm were deposited. Mechanical property measurements were obtained by finite element modeling of nanoindentation load-displacement curves. The film hardness values were about 20% below the average of the component layers and relatively independent of the layer thickness. TEM revealed deterioration of the multilayer structure when the sublayer thickness was below 15 nm due to implantation damage of the hard layers caused by the energetic C{sup +} ions of the soft layers (-2000 V bias) deposited over them. Pin-on-disk wear tests show that the wear rate drops when sublayer thickness is decreased below 20 nm and remains constant with further decreases in the layer thickness
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Growth and mechanical and tribological characterization of multi-layer hard carbon films
Vacuum-arc deposition is used to deposit multilayer C films by modulating the sample bias during deposition. Effect of varying the sublayer thickness in multilayer films consisting of alternating layers of ``hard`` (68.4 GPa, -100 V bias) and ``soft`` (27.5 GPa, - 200 V bias) was investigated. Films consisting of equal thickness layers of hard and soft material and an individual layer thickness varying from 10 to 35 nm were deposited. Mechanical property measurements were obtained by finite element modeling of nanoindentation load-displacement curves. The film hardness values were about 20% below the average of the component layers and relatively independent of the layer thickness. TEM revealed deterioration of the multilayer structure when the sublayer thickness was below 15 nm due to implantation damage of the hard layers caused by the energetic C{sup +} ions of the soft layers (-2000 V bias) deposited over them. Pin-on-disk wear tests show that the wear rate drops when sublayer thickness is decreased below 20 nm and remains constant with further decreases in the layer thickness
Evolving trends in consumption of direct oral anticoagulants in 65 countries/regions from 2008 to 2019
Background: Direct oral anticoagulants (DOACs) have been increasingly utilised over warfarin. However, little is known about the relative consumption trends and costs of each DOAC at the global level. Methods: An ecological study using pharmaceutical sales data from IQVIA-MIDAS database was used to estimate consumption and cost of individual DOACs in 65 countries from 2008 to 2019. Consumption was estimated from the volume of DOACs sold, expressed as defined-daily-dose/1000-inhabitants/day (DDDTID). Compound and absolute annual growth rates were reported to quantify consumption changes over time. Costs were estimated as manufacturer price per day-of-therapy. Results: Global consumption of dabigatran, rivaroxaban, apixaban and edoxaban were 0.31, 1.05, 1.08 and 0.78 DDDTID, respectively, in Q2â2019, compared to 0.23, 0.54, 0.21 and 0.03 in Q2â2015, with highest consumption in Western Europe, Northern Europe and Oceania (18.2, 14.07, 13.14 DDDTID). In most countries (46/65, 70%), rivaroxaban contributed to most DOAC consumption (35%â100%), whereas dabigatran accounted for less than one-third. Edoxaban accounted for < 20% of the total in Northern America and Europe but contributed significant proportions in Japan (28.58%) and South Korea (31.37%). Longer median time-to-adoption from FDA approval for apixaban and edoxaban was observed. Costs of all DOACs were ~2â4 times higher in the USA, Puerto Rico and Thailand than in other countries. Conclusions: Regional differences exist in consumption pattern and trends of individual DOACs over the past decade. Consumption of rivaroxaban and apixaban overtook dabigatran in most countries, whereas use of edoxaban remains limited except in East Asian countries. The USA pays higher prices for DOACs than other countries
Cost-effectiveness of Midazolam versus Haloperidol versus Olanzapine for the management of acute agitation in the Accident and Emergency department
Objectives: A multicenter randomized clinical trial in Hong Kong Accident and Emergency (A&E) departments concluded that intramuscular (IM) olanzapine is noninferior to haloperidol and midazolam, in terms of efficacy and safety, for the management of acutely agitated patients in A&E setting. Determining their comparative cost-effectiveness will further provide an economic perspective to inform the choice of sedative in this setting. Methods: This analysis used data from a randomized clinical trial conducted in Hong Kong A&E departments between December 2014 and September 2019. A within-trial cost-effectiveness analysis comparing the 3 sedatives was conducted, from the A&E perspective and a within-trial time horizon, using a decision-analytic model. Sensitivity analyses were also undertaken. Results: In the base-case analysis, median total management costs associated with IM midazolam, haloperidol, and olanzapine were Hong Kong dollar (HKD) 1958.9 (US dollar [USD] 251.1), HKD 2504.5 (USD 321.1), and HKD 2467.6 (USD 316.4), respectively. Agitation management labor cost was the main cost driver, whereas drug costs contributed the least. Midazolam dominated over haloperidol and olanzapine. Probabilistic sensitivity analyses supported that midazolam remains dominant > 95% of the time and revealed no clear difference in the cost-effectiveness of IM olanzapine versus haloperidol (incremental cost-effectiveness ratio 667.16; 95% confidence interval â770.89, 685.90). Conclusions: IM midazolam is the dominant cost-effective treatment for the management of acute agitation in the A&E setting. IM olanzapine could be considered as an alternative to IM haloperidol given that there is no clear difference in cost-effectiveness, and their adverse effect profile should be considered when choosing between them
Cognitive Learning Styles and Digital Equity: Searching for the Middle Way
This research is driven by a desire to understand the lifelong learner in the context of styles of learning and the emerging implications of technology enhanced learning for digital equity. Recognizing cognitive learning styles is the first step educators need to take in order to be most effective in working with students of diversity and bridging across formal and informal settings. Learning environments as a characterising feature of learning styles have undergone unprecedented change over the past decade with learning environments now blending physical and virtual space. To support the increasing diversity of learners pedagogy has to be fair, culturally responsive, equitable and relevant to the âvirtual generationâ. This in turn will inform our understanding of the âmiddle wayâ in recognising cognitive learning styles , associated cultural context, and the implications to digital pedagogy equity