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Engineering mechanical resonances of magnetoelectric transducers
Get PDFFunding: JFB acknowledges funding from Beverly and Frank MacInnis via a scholarship from the University of St Andrews and from the DFG-funded Research Training Group “Template-Designed Organic Electronics 634 (TIDE)”, RTG2591. This work also received financial support through the Alexander von Humboldt foundation (Humboldt Professorship to MCG).Magnetoelectric transducers are being investigated as a promising alternative for wireless power transfer in cases where small device size and/or low operation frequency are desired. To maximize the output power of such transducers, operation at their mechanical resonance frequency is imperative. However, a reduction in size along the direction of oscillation is intrinsically accompanied by an increase in resonance frequency. Here, we report on a computational shape optimization strategy to minimize the resonance frequency in magnetoelectric transducers by ≈38% within a set of given optimization constraints. We show that our algorithm can be used to guide the design of magnetoelectric transducers optimized to operate at different resonance frequencies and allows for consistent frequency spacing between transducers, thus enabling separately addressable devices and clustered operation. Finally, we propose four needle-shaped devices that could be used as bioimplants that impose minimal tissue damage upon direct insertion into tissue. The increase in resonance frequency associated with the needle shape is overcompensated by a frequency minimization step. Our work paves the way for computationally guided resonance frequency tuning in the field of magnetoelectric transducers.Peer reviewe
Interspecific interactions : investigating the role of grey seals in the harbour seal decline
No full textSympatric species can interact within and between trophic levels, having top-down and bottom-effects on the structure of ecological communities. Over the past 20 years, grey seal (Halichoerus grypus) and harbour seal (Phoca vitulina) populations around the UK have experienced contrasting population trends, with grey seals stable or increasing, and harbour seals suffering regional declines. Grey and harbour seals have the potential to interact through competition and predation, and so adverse interactions with grey seals is a potential driver to these harbour seal declines. I investigated interspecific interactions between seal species through changes in diet derived from prey hard parts analysis of scat samples (Chapter 2), individual variation in foraging behaviour from GPS tracking devices (Chapter 3), and evidence of predation in strandings reports and citizen science observations (Chapter 4). I demonstrated changes to the dietary niche of harbour seals through time, e.g. in the Moray Firth, the summer diet diversified between 1988 (D = 3.98 ± 0.61) and 2010 (7.16 ± 0.53). Over the same period, grey seal diet remained highly specialised on calorific sandeels (>98% biomass). From tracking data, there was no evidence of harbour seals working harder between 2012 and 2016/17; two points in time representing an increase in grey seal density of >50%. However, harbour seals were moderately repeatable in trip metrics and had higher levels of individual specialisation in 2012 which could be interpreted as intraspecific competition being a more dominant force than interspecific competition in this year. Finally, by analysing strandings data and citizen science reports from around Scotland, I demonstrated that grey seal predation of harbour seals is widespread and increased in the strandings data between 2010 and 2021. The highest odds for predation as cause of death were found in the East Scotland Seal Monitoring Unit (SMU), on adult harbour seals, and during their summer breeding season. I also modelled different predation scenarios for the SMU and demonstrated that observed levels of predation could be largely responsible for the observed annual declines of up to 21%. The results of these studies combined provide evidence that interactions with grey seals could have contributed to regional declines, and continued pressures imposed through competition and predation will make it challenging for depleted populations of harbour seals to recover
Recontextualising a singing treasure : Eve De Castro-Robinson’s Clarion
Get PDFThis paper is partially presented as a personal narrative or piece of autoethnography. What follows is an account of how I came to commission a new trumpet concerto by leading New Zealand composer Eve De Castro-Robinson’s for trumpet and pūtātara (name given to a conch shell adapted with a wooden mouthpiece by the Māori people). Over the past four decades traditional Māori instruments from New Zealand (called taonga pūoro or ‘singing treasures’) have had a major revival in the hands of musicians, scholars and instrument makers. The writing considers what I feel to be the ethical considerations of playing a when I myself am Pākehā (of European descent).Non peer reviewe
Techno-optimism versus techno-reality : an analysis of internationally funded technological solutions against illegal unreported and unregulated (IUU) fishing in Ghana and Guinea-Bissau
Get PDFFunding: The research for this article has been funded by a grant from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme [grant agreement No 803335, ‘The Lorax project: understanding ecosystemic politics’].Maritime governance has been immersed in growing techno-optimism. Technological developments have largely increased the capacity of states to render legible activities at sea and thus more effectively govern them. One area in which such techno-optimism has gained force but is yet to prove itself is the fight against Illegal, Unreported, and Unregulated (IUU) fishing. While technology-aided international cooperation has been crucial in curbing piracy, it has been slower to tame IUU fishing. In this article, we study international projects introducing technology-based solutions against IUU fishing in West Africa. Triangulating project documentation, donor evaluations, interviews, and other secondary sources, we assess how the techno-optimism driving those initiatives meets the techno-reality of their contexts of implementation. We find that, while grounds for optimism are far from unwarranted, realizing the potential of technological solutions against IUU fishing requires securing parallel cooperation that allows states to transform technology-based awareness into action.Peer reviewe
Microbial communities and soil greenhouse gas fluxes from subtropical tidal and supratidal wetlands
Get PDFFunding: The authors want to thank the Mexican Council of Science and Technology (CONACyT) for financial support. S.T-T. was supported by an ARC DECRA (DE210101029).Coastal wetlands are sinks of atmospheric carbon, but they can also emit greenhouse gases (GHGs) such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) from aerobic and anaerobic microbial soil respiration. The amount and direction of fluxes (emissions or uptakes) are variable and likely to depend on the soil microbial community and other environmental factors, such as salinity. Yet few studies have simultaneously measured GHG fluxes, microbial communities and environmental drivers in wetlands across an intertidal gradient. In this study, we sampled fringe mangroves (FM), basin mangroves (BM), saltmarsh (SM), and supratidal forests (SF) in the subtropical east coast of Australia. We found that CO2 and N2O emissions decreased landwards, from the FM to the SF, while CH4 fluxes increased. The beta diversity of bacterial and archaea communities differed significantly among wetland types. Desulfobacterota were common in mangroves, suggesting sulphate reduction, which is responsible for damping CH4 emissions, whereas the presence of Nitrososphaeria on the SF suggests nitrogen cycling, such as nitrification-denitrification, associated with N2O emissions. Salinity was strongly associated with the variation in microbial communities and the N2O and CH4 fluxes. Thus, interstitial salinity and wetland type can explain and potentially predict microbial community composition and their associated GHG fluxes within the intertidal.Peer reviewe
Speaking the host language : how Salmonella effector proteins manipulate the host
Get PDFFunding: T.L.M.T. is supported by a Biotechnology and Biological Sciences Research Council (BBSRC) David Phillips Fellowship (BB/R011834/1) and a Medical Research Council (MRC) Research Grant MR/V031058/1, which also funds I.D.D.O. and J.M. This work was also supported by the Francis Crick Institute which receives its core funding from Cancer Research United Kingdom (CC 2075), the United Kingdom Medical Research Council (CC 2075), and the Wellcome Trust (CC 2075) to T.D.P. J.S.P. is supported by a Sylvia and Charles Viertel Senior Medical Research Fellowship (SMRF22008).Salmonella injects over 40 virulence factors, termed effectors, into host cells to subvert diverse host cellular processes. Of these 40 Salmonella effectors, at least 25 have been described as mediating eukaryotic-like, biochemical post-translational modifications (PTMs) of host proteins, altering the outcome of infection. The downstream changes mediated by an effector’s enzymatic activity range from highly specific to multifunctional, and altogether their combined action impacts the function of an impressive array of host cellular processes, including signal transduction, membrane trafficking, and both innate and adaptive immune responses. Salmonella and related Gram-negative pathogens have been a rich resource for the discovery of unique enzymatic activities, expanding our understanding of host signalling networks, bacterial pathogenesis as well as basic biochemistry. In this review, we provide an up-to-date assessment of host manipulation mediated by the Salmonella type III secretion system injectosome, exploring the cellular effects of diverse effector activities with a particular focus on PTMs and the implications for infection outcomes. We also highlight activities and functions of numerous effectors that remain poorly characterized.Peer reviewe
Reynolds, Susan, 1929-2021
No full textSusan Reynolds was elected to the British Academy after she had worked out a new framework for the medieval history of England, France, Germany and northern Italy. The breakthrough book was her Kingdoms and Communities in Western Europe 900–1300 (1984); it brought all levels of society together in a synthesis, and was a stunning achievement. Her subsequent Fiefs and Vassals (Oxford, 1994) left a generation reluctant even to use the word ‘feudalism’, and other important contributions continued until not long before she died. In 2001 she was honoured with a Festschrift entitled Law, Laity and Solidarities.Non peer reviewe
Aagenaes syndrome/lymphedema cholestasis syndrome 1 is caused by a founder variant in the 5'-untranslated region of UNC45A
Get PDFBackground & Aims Lymphedema cholestasis syndrome 1 or Aagenaes syndrome is a condition characterized by neonatal cholestasis, lymphedema, and giant cell hepatitis. The genetic background of this autosomal recessive disease was unknown up to now. Methods A total of 26 patients with Aagenaes syndrome and 17 parents were investigated with whole-genome sequencing and/or Sanger sequencing. PCR and western blot analyses were used to assess levels of mRNA and protein, respectively. CRISPR/Cas9 was used to generate the variant in HEK293T cells. Light microscopy, transmission electron microscopy and immunohistochemistry for biliary transport proteins were performed in liver biopsies. Results One specific variant (c.-98G>T) in the 5’-untranslated region of Unc-45 myosin chaperone A (UNC45A) was identified in all tested patients with Aagenaes syndrome. Nineteen were homozygous for the c.-98G>T variant and seven were compound heterozygous for the variant in the 5’-untranslated region and an exonic loss-of-function variant in UNC45A. Patients with Aagenaes syndrome exhibited lower expression of UNC45A mRNA and protein than controls, and this was reproduced in a CRISPR/Cas9-created cell model. Liver biopsies from the neonatal period demonstrated cholestasis, paucity of bile ducts and pronounced formation of multinucleated giant cells. Immunohistochemistry revealed mislocalization of the hepatobiliary transport proteins BSEP (bile salt export pump) and MRP2 (multidrug resistance-associated protein 2). Conclusions c.-98G>T in the 5’-untranslated region of UNC45A is the causative genetic variant in Aagenaes syndrome.Peer reviewe
Scalable production of tissue-like vascularized liver organoids from human PSCs
Get PDFFunding: GJS, SB, and SPH were partly supported by the Research Council of Norway through its Centres of Excellence funding scheme (project number 262613), and financial support from UiO:Life Science (Project MORGI-20493) is gratefully acknowledged. GJS and RS were supported by the Research Council of Norway through project number 247624. This work was also supported by the Norwegian Center for Stem Cell Research and National Core Facility for Human Pluripotent Stem Cells. MEC, EA, PMS were partly supported by South-Eastern Norway Regional Health Authority (HSØ) (project number 2019071). Mass spectrometry-based proteomic analyses were performed by the Proteomics Core Facility, Department of Immunology, University of Oslo/Oslo University Hospital, which is supported by the Core Facilities program of the South-Eastern Norway Regional Health Authority. This core facility is also a member of the National Network of Advanced Proteomics Infrastructure (NAPI), which is funded by the Research Council of Norway INFRASTRUKTUR-program (project number: 295910). JJW is grateful to Rosetrees Trust for their interdisciplinary award. FB is partially funded by the Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 812616. EM and KSÅ were supported by the Research Council of Norway through project number 275124. DC and JM were supported by Progres Q40/06.The lack of physiological parity between 2D cell culture and in vivo culture has led to the development of more organotypic models, such as organoids. Organoid models have been developed for a number of tissues, including the liver. Current organoid protocols are characterized by a reliance on extracellular matrices (ECMs), patterning in 2D culture, costly growth factors and a lack of cellular diversity, structure, and organization. Current hepatic organoid models are generally simplistic and composed of hepatocytes or cholangiocytes, rendering them less physiologically relevant compared to native tissue. We have developed an approach that does not require 2D patterning, is ECM independent, and employs small molecules to mimic embryonic liver development that produces large quantities of liver-like organoids. Using single-cell RNA sequencing and immunofluorescence, we demonstrate a liver-like cellular repertoire, a higher order cellular complexity, presenting with vascular luminal structures, and a population of resident macrophages: Kupffer cells. The organoids exhibit key liver functions, including drug metabolism, serum protein production, urea synthesis and coagulation factor production, with preserved post-translational modifications such as N-glycosylation and functionality. The organoids can be transplanted and maintained long term in mice producing human albumin. The organoids exhibit a complex cellular repertoire reflective of the organ and have de novo vascularization and liver-like function. These characteristics are a prerequisite for many applications from cellular therapy, tissue engineering, drug toxicity assessment, and disease modeling to basic developmental biology.Peer reviewe
Cultural analytics in the UK : events data potential for the creative and cultural industries
Get PDFFunding: This work was supported by the Arts and Humanities Research Council [grant number AH/W007533/1].This article investigates the potential for novel research utilising data generated by the Creative and Cultural Industries (CCI) in the UK, focussing on the long tail of metadata associated with the UK’s rich cultural events landscape. We conducted semi-structured interviews with 29 researchers and related domain experts to ascertain: (1) How cultural data is valued; (2) The landscape of cultural data; (3) How UK research can make better use of cultural events data; (4) The benefits and pitfalls of an evidence-based approach to cultural policy; and (5) The repercussions of the Covid-19 pandemic on how data-led work is positioned within the CCI. We advocate for the potential value of cultural events data to academic research, policy and industry, and also for a humanities-led approach. We suggest that a centralised cultural events data service for use in research, industry and policy is one way of supporting this.Peer reviewe
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