Publications by authors named "Gethin D"

A novel method for determining the yield of bacterial growth using square wave voltammetry and screen printed electrodes is described here. This procedure was shown to be a reliable and accurate way to quickly determine the level of bacterial growth within culturing media and these results suggest that the combination of such sensors and the application of square wave voltammetry is suitable for applications such as within a bioreactor where the rapid determination of bacterial growth may be necessary.

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The ability to maintain body temperature has been shown to bring about improvements in sporting performance. However, current solutions are limited with regards to flexibility, heating uniformity and robustness. An innovative screen-printed Nanocarbon heater is demonstrated which is robust to bending, folding, tensile extensions of up to 20% and machine washing.

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For wearable electronic devices to be fully integrated into garments, without restricting or impeding movement, requires flexible and stretchable inks and coatings, which must have consistent performance and recover from mechanical strain. Combining Carbon Black (CB) and ammonia plasma functionalized Graphite Nanoplatelets (GNPs) in a Thermoplastic Polyurethane (TPU) resin created a conductive ink that could stretch to substrate failure (>300% nominal strain) and cyclic strains of up to 100% while maintaining an electrical network. This highly stretchable, conductive screen-printable ink was developed using relatively low-cost carbon materials and scalable processes making it a candidate for future wearable developments.

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An active ink composed of cellulose nanofibrils and silver nanowires was deposited on flexible and transparent polymer films using the bar coating process, achieving controlled thicknesses ranging from 200 nm up to 2 μm. For 350 nm thick coating on polyethylene terephthalate films, high transparency (75.6% transmittance) and strong reduction of bacterial growth equal to 89.

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Three species of cactus whose spines act as dew harvesters were chosen for this study: Copiapoa cinerea var. haseltoniana, Mammillaria columbiana subsp. yucatanensis and Parodia mammulosa and compared with Ferocactus wislizenii whose spines do not perform as dew harvesters.

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Nanocellulose has a variety of advantages, which make the material most suitable for use in biomedical devices such as wound dressings. The material is strong, allows for production of transparent films, provides a moist wound healing environment, and can form elastic gels with bioresponsive characteristics. In this study, we explore the application of nanocellulose as a bioink for modifying film surfaces by a bioprinting process.

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Four species of cacti were chosen for this study: Copiapoa cinerea var. haseltoniana, Ferocactus wislizenii, Mammillaria columbiana subsp. yucatanensis and Parodia mammulosa.

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Nature has adapted different methods for surviving dry, arid, xeric conditions. It is the focus of this comparative review to pull together the relevant information gleaned from the literature that could be utilized to design moisture harvesting devices informed by biomimetics. Most water harvesting devices in current use are not informed by nature and those that do are usually based on a biomimetic principle that has been based on one species only.

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Antibodies were patterned onto flexible plastic films using the flexographic printing process. An ink formulation was developed using high molecular weight polyvinyl alcohol in carbonate-bicarbonate buffer. In order to aid both antibody adhesion and the quality of definition in the printed features, a nitrocellulose coating was developed that was capable of being discretely patterned, thus increasing the signal-to-noise ratio of an antibody array.

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3-Azabicyclo[3.1.0]hexane compounds were designed as novel achiral μ opioid receptor ligands for the treatment of pruritus in dogs.

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Numerical modelling of atomic force microscopy cantilever designs and experiments is presented with the aim of exploring friction mechanisms at the microscale. As a starting point for this work, comparisons between finite element (FE) models and previously reported mathematical models for stiffness calibration of cantilevers (beam and V-shaped) are presented and discrepancies highlighted. A colloid probe (comprising a plain cantilever on which a particle is adhered) model was developed, and its normal and shear interaction were investigated, exploring the response of the probe accounting for inevitable imperfections in its manufacture.

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Enantioselective synthesis of cyclopropylcarboxamides is possible by asymmetric metallation of prochiral starting cyclopropanes using s-BuLi-sparteine.

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This paper illustrates the application of a combined discrete- and finite-element simulation to the compaction of assemblies comprising both ductile and brittle particles. Through case studies, the results demonstrate the importance of using a fine mesh on the particle boundary, the effect of fragmentation and its impact on the form of the compression curve, and the effect of inclusion of ductile particles at ca. 25% by volume suppressing brittle failure mechanisms.

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