Ultrafast Bragg coherent diffraction imaging of epitaxial thin films using deep complex-valued neural networks
npj Computational Materials 10:1 (2024)
Abstract:
Domain wall structures form spontaneously due to epitaxial misfit during thin film growth. Imaging the dynamics of domains and domain walls at ultrafast timescales can provide fundamental clues to features that impact electrical transport in electronic devices. Recently, deep learning based methods showed promising phase retrieval (PR) performance, allowing intensity-only measurements to be transformed into snapshot real space images. While the Fourier imaging model involves complex-valued quantities, most existing deep learning based methods solve the PR problem with real-valued based models, where the connection between amplitude and phase is ignored. To this end, we involve complex numbers operation in the neural network to preserve the amplitude and phase connection. Therefore, we employ the complex-valued neural network for solving the PR problem and evaluate it on Bragg coherent diffraction data streams collected from an epitaxial La2-xSrxCuO4 (LSCO) thin film using an X-ray Free Electron Laser (XFEL). Our proposed complex-valued neural network based approach outperforms the traditional real-valued neural network methods in both supervised and unsupervised learning manner. Phase domains are also observed from the LSCO thin film at an ultrafast timescale using the complex-valued neural network.Shock compression experiments using the DiPOLE 100-X laser on the high energy density instrument at the European x-ray free electron laser: Quantitative structural analysis of liquid Sn
Journal of Applied Physics AIP Publishing 135:16 (2024) 165902
Barriers to healthcare-worker adherence to infection prevention and control practices in British Columbia during the coronavirus disease 2019 (COVID-19) pandemic: A cross-sectional study.
Infection control and hospital epidemiology 45:4 (2024) 474-482
Abstract:
Objective
The coronavirus disease 2019 (COVID-19) pandemic highlighted the importance of robust infection prevention and control (IPAC) practices to maintain patient and staff safety. However, healthcare workers (HCWs) face many barriers that affect their ability to follow these practices. We identified barriers affecting HCW adherence to IPAC practices during the pandemic in British Columbia, Canada.Design
Cross-sectional web-based survey.Setting
Acute care, long-term care or assisted living, outpatient, mental health, prehospital care, and home care.Participants
Eligible respondents included direct-care providers and IPAC professionals working in these settings in all health authorities across British Columbia.Methods
We conducted a web-based survey from August to September 2021 to assess respondent knowledge and attitudes toward IPAC within the context of the COVID-19 pandemic. Respondents were asked to rate the extent to which various barriers affected their ability to follow IPAC practices throughout the pandemic and to make suggestions for improvement.Results
The final analysis included 2,488 responses; 36% of respondents worked in acute care. Overall, perceptions of IPAC practice among non-IPAC professionals were positive. The main self-perceived barriers to adherence included inadequate staffing to cover absences (58%), limited space in staff rooms (57%), multibed rooms (51%), and confusing messages about IPAC practices (51%). Common suggestions for improvement included receiving more support from IPAC leadership and clearer communication about required IPAC practices.Conclusions
Our findings highlight frontline HCW perspectives regarding priority areas of improvement for IPAC practices. They will inform policy and guideline development to prevent transmission of COVID-19 and future emerging infections.Thermally activated structural phase transitions and processes in metal-organic frameworks.
Chemical Society reviews 53:7 (2024) 3606-3629
Abstract:
The structural knowledge of metal-organic frameworks is crucial to the understanding and development of new efficient materials for industrial implementation. This review classifies and discusses recent advanced literature reports on phase transitions that occur during thermal treatments on metal-organic frameworks and their characterisation. Thermally activated phase transitions and procceses are classified according to the temperaturatures at which they occur: high temperature (reversible and non-reversible) and low temperature. In addition, theoretical calculations and modelling approaches employed to better understand these structural phase transitions are also reviewed.Mechanochemically-induced glass formation from two-dimensional hybrid organic-inorganic perovskites
Chemical Science (2024)