Design of variable-radius kinematic metastructures for the control of belt drive transmission ratios

This paper seeks to address a gap in technology in belt pulley systems by applying kinematic metastructures (Hoberman rings) to develop mechanisms for variable transmission. Here, we describe a design process to enable antagonistic expansion and contraction in dual Hoberman ring belt pulleys. Our design process considers the complex aspects of geometry, component-size, tolerances and wireless motoric actuation

A practical approach to supported liquid extraction and measurement of 18 steroids in plasma and serum by targeted liquid chromatography tandem mass spectrometry

Chromatography combined with mass spectrometry is a gold standard technique for steroid measurement, however the type of sample preparation, the dynamic range and reliability of the calibration curve, the chromatographic separation and mass spectrometry settings ultimately determine the success of the method. The steroid biosynthetic pathway is conserved in higher mammals and literature demonstrates that the concentration ranges of different steroid groups are relatively comparable across species. We sought to develop a robust and reliable multi steroid targeted analysis method for blood that would have wide application across higher mammals. The method was developed following bioanalytical method validation guidelines to standards typically applied to human clinical studies, including isotopically labelled internal standards where at all possible. Here we describe the practical approach to a 96-well supported liquid extraction (SLE) method of extraction from plasma (200 µL) using an Extrahera liquid handling robot (Biotage, Sweden), including quality control samples, followed by a comprehensive separation and targeted LC-MS/MS analysis of 18 steroids in plasma (pregnenolone, progesterone, 17α-hydroxyprogesterone, 11-deoxycorticosterone, corticosterone, 11-dehydrocorticosterone, aldosterone, 11-deoxycortisol, 21-deoxycortisol, cortisol, cortisone, androstenedione, testosterone, 5α-dihydrotestosterone, dehydroepiandrosterone, estrone, 17β-estradiol and estriol). •SLE in a 96-well format of up to 74 biological plasma samples, enriched with multiple isotopically labelled internal standards, a 12-point aqueous calibration curve, and 6 serum quality controls, designed to monitor long-term performance of the method•Chromatographic separation of multiple steroids along the gradient, with ammonium fluoride mobile phase additive to improve sensitivity, followed by electrospray ionisation and constant polarity switching•Aqueous calibration standards that cover physiologically relevant ranges - high nanomolar glucocorticoids, low nanomolar androgens and picomolar ranges for estrogens and steroid intermediates.</p

The voice of the UPIC:Technology and virtual agency

I have previously situated the UPIC of Iannis Xenakis, a computer music instrument of legendary intransigence, as set apart from the mainstream of electroacoustic technologies, developing its own “voice” as the utterance of “prophetic” traces: ancient, not modern. Here, I will approach the sound of the UPIC from the perspective of Robert Hatten’s recent theory of “virtual agency.” The sounds of the UPIC confound traditional notions of meaning in music as expressive – in a human sense, and reconfigure what Brian Kane calls the “audile techniques” of a “community of listeners.” Yet the works made with this technology remain engaging and meaningful to us as music. In this paper, I will explore the idea of ‘virtual agency’ as extended to non-human agents, as figured by the events and appearances of the natural world, and consider the ways in which Xenakis allows us, as listeners, to engage with these “virtual agents” through their traces, evident in the graphism of the UPIC’s interface

Non-invasive methods of monitoring Fe3O4 magnetic nanoparticle toxicity in human liver HepaRG cells using impedance biosensing and Coherent anti-Stokes Raman spectroscopic (CARS) microscopy

Functionalized nanoparticles have been developed for use in nanomedicines for treating life threatening diseases including various cancers. To ensure safe use of these new nanoscale reagents, various assays for biocompatibility or cytotoxicity in vitro using cell lines often serve as preliminary assessments prior to in vivo animal testing. However, many of these assays were designed for soluble, colourless materials and may not be suitable for coloured, non-transparent nanoparticles. Moreover, cell lines are not always representative of mammalian organs in vivo. In this work, we use non-invasive impedance sensing methods with organotypic human liver HepaRG cells as a model to test the toxicity of PEG-Fe3O4 magnetic nanoparticles. We also use Coherent anti-Stokes Raman Spectroscopic (CARS) microscopy to monitor the formation of lipid droplets as a parameter to the adverse effect on the HepaRG cell model. The results were also compared with two commercial testing kits (PrestoBlue and ATP) for cytotoxicity. The results suggested that the HepaRG cell model can be a more realistic model than commercial cell lines while use of impedance monitoring of Fe3O4 nanoparticles circumventing the uncertainties due to colour assays. These methods can play important roles for scientists driving towards the 3Rs principle – Replacement, Reduction and Refinement

Opportunities and challenges in antimicrobial resistance policy including animal production systems and humans across stakeholders in Argentina: a context and qualitative analysis

INTRODUCTION: Gaps in antimicrobial resistance (AMR) surveillance and control, including implementation of national action plans (NAPs), are evident internationally. Countries' capacity to translate political commitment into action is crucial to cope with AMR at the human-animal-environment interface.METHODS: We employed a two-stage process to understand opportunities and challenges related to AMR surveillance and control at the human-animal interface in Argentina. First, we compiled the central AMR policies locally and mapped vital stakeholders around the NAP and the national commission against bacterial resistance. Second, we conducted qualitative interviews using a semistructured questionnaire covering stakeholders' understanding and progress towards AMR and NAP. We employed a mixed deductive-inductive approach and used the constant comparative analysis method. We created categories and themes to cluster subthemes and determined crucial relationships among thematic groups.RESULTS: Crucial AMR policy developments have been made since 1969, including gradually banning colistin in food-producing animals. In 2023, a new government decree prioritised AMR following the 2015 NAP launch. Our qualitative analyses identified seven major themes for tackling AMR: (I) Cultural factors and sociopolitical country context hampering AMR progress, (II) Fragmented governance, (III) Antibiotic access and use, (IV) AMR knowledge and awareness throughout stakeholders, (V) AMR surveillance, (VI) NAP efforts and (VII) External drivers. We identified a fragmented structure of the food production chain, poor cross-coordination between stakeholders, limited surveillance and regulation among food-producing animals and geographical disparities over access, diagnosis and treatment. The country is moving to integrate animal and food production into its surveillance system, with most hospitals experienced in monitoring AMR through antimicrobial stewardship programmes.CONCLUSION: AMR accountability should involve underpinning collaboration at different NAP implementation levels and providing adequate resources to safeguard long-term sustainability. Incorporating a multisectoral context-specific approach relying on different One Health domains is crucial to strengthening local AMR surveillance.</p

Using symbiotic empirical ethics to explore the significance of relationships to clinical ethics:Findings from the Reset Ethics research project

Background: At the beginning of the coronavirus (Covid-19) pandemic, many non-Covid healthcare services were suspended. In April 2020, the Department of Health in England mandated that non-Covid services should resume, alongside the continuing pandemic response. This ‘resetting’ of healthcare services created a unique context in which it became critical to consider how ethical considerations did (and should) underpin decisions about integrating infection control measures into routine healthcare practices. We draw on data collected as part of the ‘NHS Reset Ethics’ project, which explored the everyday ethical challenges of resetting England’s NHS maternity and paediatrics services during the pandemic. Methods: Healthcare professionals and members of the public participated in interviews and focus group discussions. The qualitative methods are reported in detail elsewhere. The focus of this article is our use of Frith’s symbiotic empirical ethics methodology to work from our empirical findings towards the normative suggestion that clinical ethics should explicitly attend to the importance of relationships in clinical practice. This methodology uses a five-step approach to refine and develop ethical theory based on a naturalist account of ethics that sees practice and theory as symbiotically related. Results: The Reset project data showed that changed working practices caused ethical challenges for healthcare professionals, and that infection prevention and control measures represented harmful barriers to the experience of receiving and offering care. For healthcare professionals, offering care as part of a relational interaction was an ethically important dimension of healthcare delivery. Conclusions: Our findings suggest that foregrounding the importance of relationships across a hospital community will better promote the ethically important multi-directional expression of caring between healthcare professionals, patients, and their families. We offer two suggestions for making progress towards such a relational approach. First, that there is a change of emphasis in clinical ethics practice to explicitly acknowledge the importance of the relationships (including with their healthcare team) within which the patient is held. Second, that organisational decision-making should take into account the moral significance afforded to caring relationships by healthcare professionals, and the role such relationships can play in the negotiation of ethical challenges.</p

Accelerated seawater ageing and fatigue performance of glass fibre reinforced thermoplastic composites for marine and tidal energy applications

The use of thermoplastic composites as a sustainable alternative to thermosets is gaining increasing popularity due to their improved recyclability at the end of life. The fatigue performance of glass fibre/acrylic, glass fibre/acrylic- polyphenylene ether, and glass fibre/epoxy specimens, under three distinct upper stress levels (R-ratio = 0.1; f = 5 Hz) was studied. S–N curves were established for these specimens both before and after immersing them for three months in seawater (temperature: 50 °C). The dry thermoplastic composites exhibited similar fatigue performance to the thermoset counterpart at higher stress levels, with thermosets showing greater endurance at lower stress levels. Interestingly, the aged specimens showed comparable fatigue endurance, with a slight advantage in favour of the thermoplastic composites and less variability in their data. This study offers important insights into the fatigue performance of thermoplastic composites, emphasising their potential as sustainable alternatives to conventional thermoset composites for various marine applications

Beyond jamming grippers:Granular material in robotics

Robot grippers based on the jamming of granular material have been studied widely in previous years. Recently, also other benefits and challenges of granular material have emerged for robotics. We discuss various functions of granular matter in robotic actuation, sensory processing, locomotion, and manipulation. We also provide a review of the design and methods of robots for moving in or on challenging granular environments. Drawing on the properties of granular material and their potential applications, we propose our unique perspectives and innovative ideas for future research and development in this field

Gaussian processes for Bayesian inverse problems associated with linear partial differential equations

This work is concerned with the use of Gaussian surrogate models for Bayesian inverse problems associated with linear partial differential equations. A particular focus is on the regime where only a small amount of training data is available. In this regime the type of Gaussian prior used is of critical importance with respect to how well the surrogate model will perform in terms of Bayesian inversion. We extend the framework of Raissi et. al. (2017) to construct PDE-informed Gaussian priors that we then use to construct different approximate posteriors. A number of different numerical experiments illustrate the superiority of the PDE-informed Gaussian priors over more traditional priors