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Robustness and sensitivity of Gd(III)-Gd(III) double electron electron resonance (DEER) measurements : comparative study of high-frequency EPR spectrometer designs and spin label variants
Get PDFFunding: This work was supported financially by the Bluston Making Connections (UK-WIS) scheme, The Royal Society (International Exchanges) and the Carnegie Trust. The Q-band spectrometer high power Q-band with cryogen-free upgrade was provided by the Wellcome Trust (099149/Z/12/Z) and the BBSRC (BB/T017740/1) respectively. The authors thank EPSRC (EP/N509759/1) and the School of Physics and Astronomy, St Andrews for studentships for SRF and EMM respectively.In this paper we explore the robustness and sensitivity of Gd(III)-Gd(III) double electron-electron resonance (DEER) distance measurements in proteins for different spectrometer designs and a three spin labels. To do this a protein was labelled at the same two positions with Gd(III) spin labels and measurements were performed on two home-built high-frequency (W-band, ~95 GHz) EPR spectrometers with different design approaches, and a commercial Q-band spectrometer. The first W-band measurement approach uses a conventional, narrow band single mode cavity, while the second approach uses a broad band non-resonant induction mode sample holder. Both systems incorporate advanced arbitrary waveform generators (AWGs) that give flexibility over excitation bandwidth. We use three DOTA-like Gd(III) spin labels, Gd.C12, Gd.DO3A and the new Gd.L1, conjugated to the model protein calmodulin. We compare measurements taken by including or excluding the excitation of the Gd(III) central transition. The advantages and disadvantages of the EPR spectrometers for the measurement of Gd(III)-Gd(III) DEER are discussed in terms of the robustness of the resulting distance distribution width, absolute and concentration sensitivity, sample handling, ease of use, and flexibility of measurement.Peer reviewe
Industry 4.0: skills for the future and learning development
Get PDFThe world and the workforce are changing with the rise of Industry 4.0, or the Fourth Industrial Revolution, with a shift towards automation and digital technology, and this is coupled with other global shifts such as the climate crisis. Organisations such as the World Economic Forum, the International Labour Organisation, and Skills Development Scotland believe Industry 4.0 will change the way we work and live, with implications for everyone. These organisations argue that we need to become lifelong learners and develop future-ready skills, most notably adaptability, creativity, critical thinking, and problem-solving. But what does this mean for Learning Developers? Firstly, we need to consider how and if our own roles will change, and secondly the impact this will have on our learners and what (if any) changes we should make to support them
Long-term recordings of arcuate nucleus kisspeptin neurons across the mouse estrous cycle
Get PDFFunding: This work was supported by the Wellcome Trust (212242/Z/18/Z). We thank William Colledge (University of Cambridge, UK) for the generous provision of the Kiss1-Cre mouse line.The arcuate nucleus kisspeptin (ARNKISS) neurons represent the GnRH pulse generator that likely drives pulsatile gonadotropin secretion in all mammals. Using an improved GCaMP fiber photometry system enabling long-term continuous recordings, we aimed to establish a definitive profile of ARNKISS neuronal activity across the murine estrous cycle. As noted previously, a substantial reduction in the frequency of ARNKISS neuron synchronization events (SEs) occurs on late proestrus and extends into estrus. The SE amplitude remains constant throughout the cycle. During metestrus, we unexpectedly detected many multipeak SEs where many SEs occurred rapidly, within 160 seconds of each other. By applying a machine learning-based, k-means clustering analysis, we were further able to detect substantial within-stage variability in the patterns of pulse generator activity. Estrous cycle-dependent changes in SE activity occurred around the time of lights on and off. We also find that a mild stressor such as vaginal lavage reduces ARNKISS neuron SE frequency for up to 3 hours. These observations provide a comprehensive account of ARNKISS neuron activity across the estrous cycle, highlight a new pattern of multipeak SE activity, and introduce a new k-means clustering approach for analyzing ARNKISS neuron population behavior.Peer reviewe
From Augustus’s soup to Augustus Gloop : punishing ‘bad eaters’ in children’s literature and beyond
Get PDFWhile previous accounts of the function of food in children’s literature have mainly focused on fiction, this article examines nineteenth-century poetry and drama where ‘bad eating’ is constructed as a form of anti-social behaviour that children should be warned against and should learn to despise in others as well as themselves. Poetry for children, throughout the century, is designed to be repeated orally, often learned by heart and thus internalised: its emblematic characters, secured in memory by rhyme and metre, therefore have particular staying power in childhood consciousness that makes the trope of the ‘bad eater’ especially durable. Theatrical representations, likewise, serve to set the image of the unruly child eater within comic traditions that offer his or her body as an absurd spectacle at which the audience can confidently scoff. These tropes and images have a literary longevity that both reflects and sustains aspects of blame around ‘anti-social’ eating, which children internalise from a young age.Peer reviewe
Surface energy level and ambient photoemission characterisation of metals and semiconductors for optoelectronic and sensing applications
No full textThe accurate measurement of energy levels within metals and semiconductors is essential to informing the design of future device architectures. Within this thesis, the Kelvin probe is used to provide highly accurate characterisation of energy levels within a wide range of materials, from elementary metals such as copper and zinc to multi-halide perovskites and polymer blends.
A combination of ambient photoemission spectroscopy, contact potential difference and absorption spectroscopy is used to characterise a series of multi-halide perovskite thin films for applications in indoor light harvesting, with a halide stoichiometry – iodine:bromine:chlorine – of 2.6 : 0.2 : 0.2 determined to give the best results, before being applied to experimentally confirm DFT calculations of an intercalated bromine perovskite, the first of its kind to be reported in literature, with experimental values agreeing well with the modelled perovskite.
Brass was studied as a model material for the mixing of materials into one sample, before this model was applied to polymer:fullerene blends of P3HT:PC₆₁BM and MEH-PPV:PC₆₁BM, with an overall aim of producing a model which could be applied to additional blends of organic molecules. The results showed that blends cannot always be treated as a simple superposition of components, with crystallinity of one or more component molecules showing a tendency to skew the results, necessitating corrective factors.
Finally, the surface scanning method of contact potential difference was used, complemented by surface-enhanced Raman spectroscopy, to develop a Kelvin probe-based sensor which was able to detect PFAS molecules reliably down to environmentally relevant concentrations
Modeling the contributions of capacity and control to working memory development
Get PDFAdults are known to have superior working memory to children, but whether this improvement is driven primarily by differences in storage capacity or attentional control is debated. In particular, the understanding of how capacity and control influence the development of working memory is hampered by the fact that most theorizing about the effect of variation in either on behavior has been verbal. To address this, we extended a computational model of working memory to clearly separate the contributions of capacity and control, fitting the model to a recent developmental study. We find that the combined influence of capacity and control on working memory may be more complicated than previously appreciated. In particular, the general pattern of qualitative differences between children and adults could be produced by increasing either capacity or control alone. These results point to a need for additional experimental paradigms to clearly parse the differential impact of working memory components
Are treatment services ready for the use of big data analytics and artificial intelligence in managing opioid use disorder?
No full textFunding: Support for this research was provided by the Commonwealth Fund.In this viewpoint, we explore the use of big data analytics and artificial intelligence (AI) and discuss important challenges to their ethical, effective, and equitable use within opioid use disorder (OUD) treatment settings. Applying our collective experiences as OUD policy and treatment experts, we discuss 8 key challenges that OUD treatment services must contend with to make the most of these rapidly evolving technologies: data and algorithmic transparency, clinical validation, new practitioner-technology interfaces, capturing data relevant to improving patient care, understanding and responding to algorithmic outputs, obtaining informed patient consent, navigating mistrust, and addressing digital exclusion and bias. Through this paper, we hope to critically engage clinicians and policy makers on important ethical considerations, clinical implications, and implementation challenges involved in big data analytics and AI deployment in OUD treatment settings.Peer reviewe
Self-directed and prosocial wound care, snare removal, and hygiene behaviors amongst the Budongo chimpanzees
Get PDFFunding: EF was funded by the Clarendon Fund, Keble College, Oxford, and the Explorers Club. CH received funding from the European Union’s 8th Framework Program, Horizon 2020, under grant agreement no. 802719. Open Access to this article is financed by FCT – Fundação para a Ciência e a Tecnologia, within the scope of the project UID/04211Understanding the cognitive and social foundations of healthcare behaviors in humans requires examining their evolutionary precursors in our closest living relatives. Investigating self-directed and other-directed healthcare in chimpanzees provides crucial insights into the origins of medicinal knowledge, identification of specific medicinal resources used for health maintenance, and the emergence of prosocial healthcare capacities. Here we document and analyze both previously reported and newly observed instances of self-directed and other-directed wound care, snare removal, and putatively medicinal hygiene behaviors in the Sonso and Waibira chimpanzee communities of the Budongo Forest in Uganda. Reports of these behaviors come from archival records collected from over thirty years of observation at the Budongo Conservation Field Station (BCFS), videos recorded by researchers at the site, and all-occurrence behavioral data collected over two 4-month periods of direct observation. We describe self-directed wound care behaviors such as wound licking, leaf-dabbing, pressing fingers to wounds, and the application of chewed plant material to wounds, as well as a successful self-directed snare removal. We also document self-directed hygiene behaviors including postcoital genital leaf wiping and post-defecation leaf wiping. For the first time in Budongo, we report the presence of prosocial wound care, adding to similar observations documented at other chimpanzee field sites. We present cases of individuals licking, finger pressing, and applying chewed plant material to the wounds of others. We also establish the presence of prosocial postcoital hygiene behaviors, specifically postcoital leaf wiping. Lastly, we report an additional unpublished case of prosocial snare removal. The presence of prosocial-care behaviors between both kin and non-kin individuals at Budongo adds another site to the growing list of locations where such behaviors have been documented, suggesting prosocial healthcare is more widespread across chimpanzee populations than previously recognized.Peer reviewe
Surviving colonies of Pseudomonas aeruginosa isolated in vivo from infected, antibiotic-treated Galleria mellonella larvae acquire an antibiotic-tolerant phenotype
Get PDFFunding: A.M. and P.J.C. were funded by the University of St Andrews. The Salipante lab maintains the P. aeruginosa deletion strain collection and was supported by the Cystic Fibrosis Foundation (Grant SINGH24R0).Background: The aim of this work was to induce the formation of antibiotic-tolerant and/or persister cells in vivo using antibiotic therapy on Galleria mellonella larvae infected with P. aeruginosa, isolate these surviving cells, and characterise their phenotype and genotype. Methods: Infected larvae were treated with effective doses of either ceftazidime or meropenem. Despite this, surviving P. aeruginosa colonies were isolated from living larvae, and antibiotic killing, fitness, virulence, antibiotic resistance and the whole genome sequence of a selection of these isolates were compared with their original parent strains. Results: The surviving isolates had an increased minimum duration to kill 99% of the population (MDK99) upon exposure to ceftazidime or meropenem and decreased growth rates in culture, but they showed no change to the MIC or virulence—consistent with an antibiotic-tolerant phenotype. Long-read genome sequencing of selected isolates revealed only one single nucleotide polymorphism (SNP) within bkdB, encoding the lipoamide acyltransferase component of the branched-chain α-keto acid dehydrogenase, present in two independent isolates. However, time-kill assays with ceftazidime of bkdB knockout strains showed no significant change in the MDK99. Concomitant with the antibiotic-tolerant phenotype, many of the isolates also had a reduced rate of killing when exposed to heat stress. Conclusions: P. aeruginosa cells that survived antibiotic therapy in vivo were found to be antibiotic-tolerant and thermotolerant but not antibiotic-resistant and had reduced growth rates under optimal conditions but unchanged virulence. In the absence of a convincing genetic explanation, the co-induction of enhanced thermotolerance with antibiotic tolerance indicated that both are conferred by a heritable phenotypic mechanism.Peer reviewe
Retrospective review on reticular materials : facts and figures over the last 30 years
Get PDFFunding: AVD thanks the Faraday Institution (Grants – FIRG018, FIRG064) for funding. RE and EEP the Fonds der Chemischen Industrie for a Liebig Fellowship. SMV thanks the Catalyst Design for Decarbonization Center, an Energy Frontier Research Center (EFRC) funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences (DE-SC0023383), for funding. JDE is the recipient of an Australian Research Council Discovery Early Career Award (project number DE220100163) funded by the Australian Government.The field of reticular materials, such as metal–organic frameworks (MOFs) and covalent organic frameworks (COFs), is expanding continuously – be it in terms of novel structures, advanced characterization techniques, or record-breaking physical properties for applications. This timeline review reflects on the progress over the past 30 years, complemented by input from the community of active researchers. Owing to a global, crowdsourced survey of 228 researchers that is conducted through an online questionnaire, recent insights into the demographics of the field are given. Besides revealing how it works, publish, and interact, the review highlights both academic and industrial milestones. The contemporary trends are described, both at the level of material development and their suitability for a range of applications. To pave the way for newcomers to the field, some remaining challenges and steps to overcome them are discussed. The findings from this contemplative review aim to shape the future course of research in this domain.Non peer reviewe
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