A mixed methods study of Aboriginal health workers' and exercise physiologists' experiences of co-designing chronic lung disease 'yarning' education resources.

BACKGROUND: Despite the high incidence of chronic obstructive pulmonary disease (COPD) in Aboriginal communities in Australia, Aboriginal Health Workers (AHWs) have limited knowledge about effective management. AIM: To evaluate an online education program, co-designed with AHWs and exercise physiologists (EPs) or physiotherapists (PTs), to increase knowledge about COPD and its management. METHODS: AHWs and EPs from four Aboriginal Community Controlled Health Services (ACCHS) were recruited. An Aboriginal researcher and a physiotherapist experienced in COPD management and pulmonary rehabilitation (PR) delivered seven online education sessions. These sessions used co-design principles and an Aboriginal pedagogy framework '8 Ways of learning', which incorporates Aboriginal protocols and perspectives to realign teaching techniques and strengthen learning outcomes. Topics covered were: How the lungs work; What is COPD; Medications and how to use inhalers and COPD Action Plans; Why exercise is important; Managing breathlessness; Healthy eating; Managing anxiety and depression. After each session, AHWs with support from EPs, co-designed education 'yarning' resources using Aboriginal ways of learning to ensure topics were culturally safe for the local Aboriginal community and practiced delivering this at the following session. At the end of the program participants completed an anonymous online survey (5-point Likert scale) to assess satisfaction, and a semi-structured interview about their experience of the online education. RESULTS: Of the 12 participants, 11 completed the survey (7 AHWs, 4 EPs). Most (90%) participants strongly agreed or agreed that the online sessions increased knowledge and skills they needed to support Aboriginal patients with COPD. All (100%) participants felt: their cultural perspectives and opinions were valued and that they were encouraged to include cultural knowledge. Most (91%) reported that delivering their own co-designed yarning scripts during the online sessions improved their understanding of the topics. Eleven participants completed semi-structured interviews about participating in online education to co-design Aboriginal 'yarning' resources. Themes identified were: revealing the Aboriginal lung health landscape; participating in online learning; structuring the online education sessions; co-designing with the facilitators. CONCLUSIONS: Online education using co-design and 8 Ways of learning was rated highly by AHWs and EPs for improving COPD knowledge and valuing cultural perspectives. The use of co-design principles supported the cultural adaptation of COPD resources for Aboriginal people with COPD. TRIAL REGISTRATION: PROSPERO (registration number: CRD42019111405).

Effectiveness of direct-acting antiviral therapy among Aboriginal and Torres Strait Islander peoples with HCV infection in Australia: A national real-world cohort (REACH-C).

Aboriginal and Torres Strait Islander peoples experience a disproportionate burden of hepatitis C virus (HCV) infection. This study assessed the effectiveness of direct-acting antiviral (DAA) therapy among Aboriginal peoples in the three years following universal access in Australia. REACH-C, a national multicentre prospective cohort study, evaluated HCV treatment outcomes from sequential DAA initiations across 33 health services between March 2016 and June 2019. DAA effectiveness was assessed by sustained virological response (SVR) in the total (full analysis set) and effectiveness (modified analysis set excluding those lost to follow-up) populations. Overall, 915 (10%) Aboriginal and 8095 (90%) non-Indigenous people commenced DAA therapy, of whom 30% and 16% reported current injecting drug use and 73% and 42% were treated in primary care, respectively. SVR in the total and effectiveness populations was 74% and 94% among Aboriginal people and 82% and 94% among non-Indigenous people, with loss to follow-up contributing to lower SVR in the total population analysis (22% Aboriginal, 13% non-Indigenous). Among Aboriginal people, returning for follow-up was positively associated with older age (aOR 1.20; 95% CI 1.04, 1.39) and SVR was negatively associated with cirrhosis (aOR 0.39; 95% CI 0.19, 0.80) and prior DAA treatment (aOR 0.14; 95% CI 0.04, 0.49). Factors reflecting higher vulnerability or inequity were not associated with returning for testing or SVR. DAA therapy was highly effective among Aboriginal peoples with HCV treated through primary and tertiary services. Tailored community-led interventions are necessary to optimize follow-up and engagement. Sustained DAA uptake and equitable access to care, treatment and prevention are required for HCV elimination.

Femtosecond Laser-Induced Crystallization of Amorphous Silicon Thin Films under a Thin Molybdenum Layer.

A new process to crystallize amorphous silicon without melting and the generation of excessive heating of nearby components is presented. We propose the addition of a molybdenum layer to improve the quality of the laser-induced crystallization over that achieved by direct irradiation of silicon alone. The advantages are that it allows the control of crystallite size by varying the applied fluence of a near-infrared femtosecond laser. It offers two fluence regimes for nanocrystallization and polycrystallization with small and large crystallite sizes, respectively. The high repetition rate of the compact femtosecond laser source enables high-quality crystallization over large areas. In this proposed method, a multilayer structure is irradiated with a single femtosecond laser pulse. The multilayer structure includes a substrate, a target amorphous Si layer coated with an additional molybdenum thin film. The Si layer is crystallized by irradiating the Mo layer at different fluence regimes. The transfer of energy from the irradiated Mo layer to the Si film causes the crystallization of amorphous Si at low temperatures (∼700 K). Numerical simulations were carried out to estimate the electron and lattice temperatures for different fluence regimes using a two-temperature model. The roles of direct phonon transport and inelastic electron scattering at the Mo-Si interface were considered in the transfer of energy from the Mo to the Si film. The simulations confirm the experimental evidence that amorphous Si was crystallized in an all-solid-state process at temperatures lower than the melting point of Si, which is consistent with the results from transmission electron microscopy (TEM) and Raman. The formation of crystallized Si with controlled crystallite size after laser treatment can lead to longer mean free paths for carriers and increased electrical conductivity.

Effects of Annealing Temperature and Ambient on Metal/PtSe2 Contact Alloy Formation.

Forming gas annealing is a common process step used to improve the performance of devices based on transition-metal dichalcogenides (TMDs). Here, the impact of forming gas anneal is investigated for PtSe2-based devices. A range of annealing temperatures (150, 250, and 350 °C) were used both in inert (0/100% H2/N2) and forming gas (5/95% H2/N2) environments to separate the contribution of temperature and ambient. The samples are electrically characterized by circular transfer length method structures, from which contact resistance and sheet resistance are analyzed. Ti and Ni are used as metal contacts. Ti does not react with PtSe2 at any given annealing step. In contrast to this, Ni reacts with PtSe2, resulting in a contact alloy formation. The results are supported by a combination of X-ray photoelectron spectroscopy, Raman spectroscopy, energy-dispersive X-ray spectroscopy, and cross-sectional transmission electron microscopy. The work sheds light on the impact of forming gas annealing on TMD-metal interfaces, and on the TMD film itself, which could be of great interest to improve the contact resistance of TMD-based devices.

Phosphorus monolayer doping (MLD) of silicon on insulator (SOI) substrates.

This paper details the application of phosphorus monolayer doping of silicon on insulator substrates. There have been no previous publications dedicated to the topic of MLD on SOI, which allows for the impact of reduced substrate dimensions to be probed. The doping was done through functionalization of the substrates with chemically bound allyldiphenylphosphine dopant molecules. Following functionalization, the samples were capped and annealed to enable the diffusion of dopant atoms into the substrate and their activation. Electrical and material characterisation was carried out to determine the impact of MLD on surface quality and activation results produced by the process. MLD has proven to be highly applicable to SOI substrates producing doping levels in excess of 1 × 1019 cm-3 with minimal impact on surface quality. Hall effect data proved that reducing SOI dimensions from 66 to 13 nm lead to an increase in carrier concentration values due to the reduced volume available to the dopant for diffusion. Dopant trapping was found at both Si-SiO2 interfaces and will be problematic when attempting to reach doping levels achieved by rival techniques.

Wide Spectral Photoresponse of Layered Platinum Diselenide-Based Photodiodes.

Platinum diselenide (PtSe2) is a group-10 transition metal dichalcogenide (TMD) that has unique electronic properties, in particular a semimetal-to-semiconductor transition when going from bulk to monolayer form. We report on vertical hybrid Schottky barrier diodes (SBDs) of two-dimensional (2D) PtSe2 thin films on crystalline n-type silicon. The diodes have been fabricated by transferring large-scale layered PtSe2 films, synthesized by thermally assisted conversion of predeposited Pt films at back-end-of-the-line CMOS compatible temperatures, onto SiO2/Si substrates. The diodes exhibit obvious rectifying behavior with a photoresponse under illumination. Spectral response analysis reveals a maximum responsivity of 490 mA/W at photon energies above the Si bandgap and relatively weak responsivity, in the range of 0.1-1.5 mA/W, at photon energies below the Si bandgap. In particular, the photoresponsivity of PtSe2 in infrared allows PtSe2 to be utilized as an absorber of infrared light with tunable sensitivity. The results of our study indicate that PtSe2 is a promising option for the development of infrared absorbers and detectors for optoelectronics applications with low-temperature processing conditions.

Fabrication of HfO2 patterns by laser interference nanolithography and selective dry etching for III-V CMOS application.

Nanostructuring of ultrathin HfO2 films deposited on GaAs (001) substrates by high-resolution Lloyd's mirror laser interference nanolithography is described. Pattern transfer to the HfO2 film was carried out by reactive ion beam etching using CF4 and O2 plasmas. A combination of atomic force microscopy, high-resolution scanning electron microscopy, high-resolution transmission electron microscopy, and energy-dispersive X-ray spectroscopy microanalysis was used to characterise the various etching steps of the process and the resulting HfO2/GaAs pattern morphology, structure, and chemical composition. We show that the patterning process can be applied to fabricate uniform arrays of HfO2 mesa stripes with tapered sidewalls and linewidths of 100 nm. The exposed GaAs trenches were found to be residue-free and atomically smooth with a root-mean-square line roughness of 0.18 nm after plasma etching.PACS: Dielectric oxides 77.84.Bw, Nanoscale pattern formation 81.16.Rf, Plasma etching 52.77.Bn, Fabrication of III-V semiconductors 81.05.Ea.