Publications by authors named "R Chadwick"

376 Publications

A Methodology for Remote Microwave Sterilization Applicable to the Coronavirus and Other Pathogens Using Retrodirective Antenna Arrays.

IEEE J Electromagn RF Microw Med Biol 2022 Mar 3;6(1):41-51. Epub 2021 May 3.

Institute of Sensors Signals and Systems, School of Engineering and Physical SciencesHeriot-Watt University EH14 4AS Edinburgh U.K.

This paper describes an innovative remote surface sterilization approach applicable to the new coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The process is based on the application of a liquid film on the surface or object under sterilization (OUS). A beacon signal is used to self-steer the transmitted power from the designed retrodirective antenna array (RDA) towards the OUS using circularly polarized fields; then, the sterilization is completed by raising and maintaining the required temperature for a certain time. Results suggest that the process takes 5 minutes or less for an angular coverage range over 60 degrees whilst abiding by the relevant safety protocols. This paper also models the power incident onto the OUS, providing consistent results with full-wave simulations. A practical RDA system is developed using a 2 × 1 microstrip patch array operating at 2.5 GHz and tested through the positioning of a representative target surface. Measurements, developed by sampling the power transmitted by the heterodyne RDA, are reported for various distances and angles, operating in the near-field of the system. To further validate the methodology, an additional experiment investigating virus deactivation through microwave heating was also developed. Measurements have been performed with an open cavity microwave oven on the Coronavirus (strain 229E) and egg white protein in a cuvette. This demonstrates that the temperature increases of aqueous films up to 70 [Formula: see text]C by remote microwave-induced heat can denature proteins and deactivate viruses. Possible applications of the method include sterilization of ambulances, medical equipment, and internet of things (IoT) devices.
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http://dx.doi.org/10.1109/JERM.2021.3077110DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8956366PMC
March 2022

Dental amalgam: the history and legacy you perhaps never knew?

Br Dent J 2022 May 13;232(9):633-637. Epub 2022 May 13.

Convenor, ISO Technical Committee 106, Subcommittee 1, Working Group 7, Dental Amalgam, International Organisation for Standardisation, Switzerland; Formerly Reader in Dental Material Science, The Dental School, Dundee, UK.

Much has been written about dental amalgam. Over many years, it has served the profession well, yet on environmental grounds its use is being phased down. This article seeks to explore key milestones in the history and development of this versatile material, as well as highlighting how international standards have assisted in reducing environmental mercury contamination.
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http://dx.doi.org/10.1038/s41415-022-4204-zDOI Listing
May 2022

What lies behind the quality assurance of your materials?

Br Dent J 2022 May 13;232(9):630-632. Epub 2022 May 13.

Professor of Operative Dentistry and Dental Materials Science, University of Dundee, UK.

In dentistry, all reputable manufacturers comply with international standards. This is important for quality assurance of dental materials. How such standards came into being and have evolved, however, is perhaps less well-known. This paper covers the necessity and formulation of standards and illustrates their application with reference to materials that may be considered as potential alternatives to dental amalgam. In addition, the uncertainties around such a framework following Brexit are summarised. Robust standards are essential for consumer protection and international trade.
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http://dx.doi.org/10.1038/s41415-022-4196-8DOI Listing
May 2022

Materials legacy - past, present and future.

Br Dent J 2022 May;232(9):585

Guest Editor BDJ Dental Materials Themed Issue andProfessor of Operative Dentistry and Dental Materials Science, The Dental School, Dundee, UK.

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http://dx.doi.org/10.1038/s41415-022-4247-1DOI Listing
May 2022

Challenges for bioethics in the new normal.

Authors:
Ruth Chadwick

Bioethics 2022 May;36(4):347

School of Social Sciences, Cardiff University, Cardiff, UK.

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http://dx.doi.org/10.1111/bioe.13038DOI Listing
May 2022
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