6,022 research outputs found
Advanced coatings through pulsed magnetron sputtering
Pulsed magnetron sputtering (PMS) has become
established as the process of choice for the deposition
of dielectric materials for many applications. The
process is attractive because it offers stable arc free
operating conditions during the deposition of, for
example, functional films on architectural and automotive
glass, or antireflective/antistatic coatings on
displays. Recent studies have shown that pulsing the
magnetron discharge also leads to hotter and more
energetic plasmas in comparison with continuous dc
discharges, with increased ion energy fluxes delivered to
the substrate. As such, the PMS process offers benefits
in the deposition of a wide range of materials. The
present paper describes three examples where PMS has
led to either significant enhancement in film properties
or enhanced process flexibility: in low friction titanium
nitride coatings, in Al doped zinc oxide transparent
conductive oxide coatings sputtered directly from
powder targets and in thin film photovoltaic devices
based on copper (indium/gallium) diselenide. These
examples demonstrate the versatility of PMS and open
up new opportunities for the production of advanced
coatings using this technique
Socioeconomic, Demographic and Policy Comparisons of Living and Deceased Kidney Transplantation Rates Across 53 Countries.
There are more than 1.7 million sufferers of end stage kidney disease (ESKD) worldwide and for many a donated kidney provides the only chance of regaining independence from dialysis. Unfortunately, the demand for kidneys for transplantation far exceeds the available supply. It is important, therefore, that we understand the factors that may influence kidney donation rates. While certain socio-demographic factors have been linked to kidney donation rates, few studies have examined the influence of multiple socio-demographic factors on rates of both living and deceased kidney transplantation (KT) and none have examined their comparative effect in large numbers of culturally and socio-politically diverse countries. In this study, we performed univariate and multivariate analyses of the influence of 15 socio-economic factors on both the living donor (LD) and the deceased donor (DD) kidney transplantation rates (KTR) in 54 countries. Our analyses demonstrated that factors such as UN HDI (United Nations Human Development Index), religion, education, age, healthcare expenditure, presumed consent legislation and existence of a nationally managed organ donation program were associated with higher deceased KTR. In contrast, the only factors associated with living KTR were a highly significant negative association with presumed consent and variable associations with different religions. We suggest that by identifying factors that affect kidney transplantation rates these can be used to develop programs for enhancing donor rates in individual countries where those rates are below the leading countries. Keywords Organ Donation, Kidney Transplantation; Living Donor Transplantation, Deceased Donor Kidneys, Socioeconomics; Public Policy; Demographics; Presumed Consent Lay summary Using data from 53 countries, this study shows that Human Development Index, religion, Gross Domestic Product (GDP), education, age, healthcare expenditure, presumed consent legislation and existence of a nationally managed organ donation programme were associated with higher deceased donation rates. For living transplants, a negative association was noted with presumed consent and variable associations with different religions. These factors could be targeted in countries with low donation rates
The future of pharmacology education: a global outlook
Pharmacology educators play a unique role in higher education, at the intersection of basic biological, and clinical sciences. They teach a on wide range of courses including undergraduate and postgraduate medicine, pharmacy, nursing, dentistry, physiotherapy, osteopathy, veterinary science and biomedical science [1]. Note that this is far from an exhaustive list. Significant changes have taken place in pharmacology education in response to advances in pharmacology, developments in educational approaches and learning technologies, changes in healthcare education delivery, and the massification and internationalization of higher education. These challenge the educator, whose role is increasingly recognized as encompassing teaching, leadership and scholarly activity [2]. The future of pharmacology education depends on our ability to navigate these changes. We argue that there are sets of interrelated knowledge, skill, and attribute competencies that pharmacology educators must master to ultimately enable their students to succeed, discussed in detail in the following sections
Visual kinematic force estimation in robot-assisted surgery – application to knot tying
Robot-assisted surgery has potential advantages but lacks force feedback, which can lead to errors such as broken stitches or tissue damage. More experienced surgeons can judge the tool-tissue forces visually and an automated way of capturing this skill is desirable. Methods to measure force tend to involve complex measurement devices or visual tracking of tissue deformation. We investigate whether surgical forces can be estimated simply from the discrepancy between kinematic and visual measurement of the tool position. We show that combined visual and kinematic force estimation can be achieved without external measurements or modelling of tissue deformation. After initial alignment when no force is applied to the tool, visual and kinematic estimates of tool position diverge under force. We plot visual/kinematic displacement with force using vision and marker-based tracking. We demonstrate the ability to discern the forces involved in knot tying and visualize the displacement force using the publicly available JIGSAWS dataset as well as clinical examples of knot tying with the da Vinci surgical system. The ability to visualize or feel forces using this method may offer an advantage to those learning robotic surgery as well as adding to the information available to more experienced surgeons
Online-based participatory design: A Case Study of Developing International Standards During a Pandemic
Standards are essential instruments to ensure the safety, efficiency and quality of products, services, systems, processes, and environments. In pre-pandemic times, standard development process used to happen through in-person consultation and meetings, however, the COVID-19 pandemic disrupted the whole routine. A team of technical experts from the National Standards Authority of Ireland trialled an online-based participatory design process to support the review and development of a standard through stakeholder engagement. This article introduces the experience of developing a new standard by leveraging on emerging digital technologies, through stakeholder participation. This research offers a framework, outlining the steps undertaken during the process, to support future online-based standard development processes in co-operation with stakeholders, by respecting cultures, backgrounds, skills, and experiences
Shadows and traces in bicategories
Traces in symmetric monoidal categories are well-known and have many
applications; for instance, their functoriality directly implies the Lefschetz
fixed point theorem. However, for some applications, such as generalizations of
the Lefschetz theorem, one needs "noncommutative" traces, such as the
Hattori-Stallings trace for modules over noncommutative rings. In this paper we
study a generalization of the symmetric monoidal trace which applies to
noncommutative situations; its context is a bicategory equipped with an extra
structure called a "shadow." In particular, we prove its functoriality and
2-functoriality, which are essential to its applications in fixed-point theory.
Throughout we make use of an appropriate "cylindrical" type of string diagram,
which we justify formally in an appendix.Comment: 46 pages; v2: reorganized and shortened, added proof for cylindrical
string diagrams; v3: final version, to appear in JHR
Profile of the most common complaints for five health professions in Australia
© 2019 AHHA. Objective: The aims of this study were to profile the most common complaints and to examine whether any demographic factors are associated with receiving a complaint for five health professions in Australia. Methods: A national cohort study was conducted for all complaints received for medicine, nursing/midwifery, dentistry, pharmacy and psychology from 1 July 2012 to 31 December 2013 (18 months). Data were collected from the Australian Health Practitioner Regulation Agency (AHPRA), the New South Wales (NSW) Health Professional Councils' Authority and the NSW Health Care Complaints Commission. The frequency and risk of complaints were summarised for the five professions and by demographic information. Results: There were 545 283 practitioners registered with AHPRA between 1 July 2012 and 31 December 2013, consisting of 20 935 dentists, 101 066 medical practitioners, 363 040 nurses/midwives, 28 370 pharmacists and 31 872 psychologists. During the study period there were 12 616 complaints, corresponding to an annual rate of 1.5 per 100 practitioners. Complaints were most common for doctors and dentists (5% per annum per practitioner) and least common for nurses/midwives (0.5% per annum per practitioner). Sex (P < 0.01), age (P < 0.01) and country of birth (P < 0.01) were all associated with risk of complaint. The most common complaints were clinical care (44% of all complaints), medication (10%) and health impairment of the practitioner (8%). Types of complaints varied by profession, sex and age. Conclusions: The risk of a complaint is low, but varies by profession and demographics. The types of complaints also vary by profession and demographics. Differences between professions is most likely driven by their different work tasks and work environments. What is already known on this subject?: Although complaints are summarised annually from state and national health regulators, no overall national summary of complaints across professions exists. Thus, it is difficult to examine which complaints are most common, how professions differ from each other or what factors may be associated with risk and type of complaint. Previous studies have primarily focused on a single profession, such as medicine, where, for example, the number of prior complaints, sex, doctor speciality and age have been found to be associated with recurrent complaints. What does this paper add?: This paper is the first of this kind to provide a national summary of all complaints from five of the most common health professions in Australia. We found that regardless of profession, men were at least twice as likely to have a complaint made against them than women. We also found that the types of complaint differed between men and women. There were similarities across professions for the most common types of complaints, but clear differences between professions were also noted. Not surprising, clinical care was typically the most common type of complaint for the five professions, but somewhat surprising was the inclusion of health impairment as one of the most common types of complaints. What are the implications for practitioners?: Identifying the most common complaints, and the factors associated with these, may assist practitioners to understand their risk(s) of complaint and could potentially assist educators and regulators develop education programs that help reduce complaints
An International Comparison of the Effect of Policy Shifts to Organ Donation Following Cardiocirculatory Death (DCD) on Donation Rates After Brain Death (DBD) and Transplantation Rates
During the past decade an increasing number of countries have adopted policies that emphasize donation after cardiocirculatory death (DCD) in an attempt to address the widening gap between the demand for transplantable organs and the availability of organs from donation after brain death (DBD) donors. In order to examine how these policy shifts have affected overall deceased organ donor (DD) and DBD rates, we analyzed deceased donation rates from 82 countries from 2000–2010. On average, overall DD, DBD and DCD rates have increased over time, with the proportion of DCD increasing 0.3% per year (p = 0.01). Countries with higher DCD rates have, on average, lower DBD rates. For every one-per million population (pmp) increase in the DCD rate, the average DBD rate decreased by 1.02 pmp (95% CI: 0.73, 1.32; p<0.0001). We also found that the number of organs transplanted per donor was significantly lower in DCD when compared to DBD donors with 1.51 less transplants per DCD compared to DBD (95% CI: 1.23, 1.79; p<0.001). Whilst the results do not infer a causal relationship between increased DCD and decreased DBD rates, the significant correlation between higher DCD and lower DBD rates coupled with the reduced number of organs transplanted per DCD donor suggests that a national policy focus on DCD may lead to an overall reduction in the number of transplants performed
Optimisation of HiPIMS photocatalytic titania coatings for low temperature deposition
Titanium dioxide in its anatase form is widely used in photocatalytic applications due to its high photocatalytic activity, stability and low cost. Titania coatings directly deposited by conventional magnetron sputtering tend to have an amorphous microstructure. For the anatase structure to develop, substrate heating or post-deposition thermal treatment is usually required, with the anatase crystal phase generally forming at temperatures in excess of 400 °C. This precludes the choice of thermally sensitive substrate materials for the photoactive coating.
Depending on the nature of the driving voltage waveform, high power impulse magnetron sputtering (HiPIMS) has been shown to deliver a relatively low thermal flux to the substrate, whilst still allowing the direct deposition of crystalline titania coatings. Consequently, this technique offers the potential to deposit photocatalytically active titania coatings directly onto polymeric substrates and, therefore, opens up a range of new applications. In the present work a range of titanium dioxide thin films were deposited by HiPIMS onto glass substrates in order to study the influence of various process parameters, such as pressure, pulse frequency and pulse duration on coating structure and photocatalytic properties. The photocatalytic properties of the coatings were assessed by their ability to degrade the organic dye methylene blue under UV and fluorescent light irradiation. The degradation rate of methylene blue was calculated by measuring its absorption peak height at 665 nm in continuous mode under UV/fluorescent light source. The hydrophilic properties of the coatings were also investigated by measuring the contact angle of water droplets on the coating surfaces. Experimentally, the optimum conditions to maximise the photocatalytic performance of the coatings were found. The influence of various deposition parameters on the photocatalytic properties and crystal structure of the coatings is discussed.
Optimised coatings then were deposited onto polymeric substrates, such as polyethylene terephthalate (PET) and polycarbonate, to assess the suitability of using this method for high-energy, low-temperature deposition of photoactive titania coatings and the relevance of the optimised condition was tested for other types of substrates other than glass. It was found that titania coatings deposited by HiPIMS directly onto polymeric substrates showed relatively high levels of activity in their as-deposited state.
The ability to deposit crystalline titania with photocatalytic functionality at temperatures low enough to enable the use of polymer substrates is a significant advancement in the field. It could potentially allow the production of high volumes of photocatalytic material on substrates, such as polymer web, which is not possible with current deposition techniques
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