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Li-stuffed garnet solid electrolytes : current status, challenges, and perspectives for practical Li-metal batteries
No full textFunding: This research was financially supported by the Advanced Low Carbon Technology Research and Development Program of Specially Promoted Research for Innovative Next Generation Batteries (ALCA-SPRING) (Grant No. JPMJAL1301) from the Japan Science and Technology Agency (JST), GIMRT program of the Institute for Materials Research of Tohoku University (Proposal No. 202308-CRKKE-0221), AIMR Fusion Research 2023, Core Research Cluster for Materials Science (CRC-MS), and Basic Research grant from TEPCO Memorial Foundation.Solid-state Li-metal batteries have gained considerable attention for next-generation energy storage because of their potential high energy densities and improved safety. Solid electrolytes are critical to the development of solid-state Li-metal batteries. While various solid electrolytes exhibit fast-ion conductivity, garnet-type oxides are among the few that show good chemical stability against Li metal. In addition, their high oxidation stability allows the use of high-voltage cathodes. However, the practical application of garnet solid electrolytes faces severe challenges: 1) difficulty in sintering thin and large-area garnet solid electrolytes, 2) large interfacial resistance between garnet electrolytes and electrode materials, and 3) Li dendrite growth. This review summarizes recent advances in garnet-type solid electrolytes and emphasizes the key challenges hindering their practical application in Li-metal batteries. Based on a comprehensive literature survey and our studies, the optimization of crystal structure and ionic conductivity in Li7La3Zr2O12 (LLZO) is nearly complete. The focus of the field is shifting from high-temperature sintered thick pellets to low-temperature processed thin and flexible LLZO-based organic/inorganic sheet electrolytes, which are more promising for commercialization. Additional research is needed to fully understand the mechanics, interface behavior, Li-ion pathway, and manufacturability of castable LLZO-based sheet electrolytes. In terms of cell energy density, the gravimetric energy density of polycrystalline LLZO-based all-solid-state Li-metal pouch cells is estimated to reach only 272 Wh kg-1 under ideal conditions.Peer reviewe
Towards maximally entangled photon pairs and single cycle quantum nonlinear interferometers
Get PDFThis work contributes to the development of maximally entangled photon pairs and single-cycle quantum nonlinear interferometers. It is both theoretical and experimental in nature.
Under pulsed pumping conditions, the entanglement of photon pairs degrades with increased pump bandwidth. This effect can be overcome by producing a difference beam state where the photon pairs are correlated instead of anti-correlated in frequency. This work identifies the criteria required to produce the maximally entangled photon pair state known as a difference beam state using four-wave mixing. It is shown that the key requirement to produce such a state experimentally is to ensure that Ω_c ≪ Ω_p ≪ Ω_EPM, where Ω_c is the width of the phasematching function, Ω_p is the pump bandwidth and Ω_EPM quantities the contribution of the second-order dispersion. I build an experimental set-up to produce photon pairs and measure the signal photons. I identify the next steps to build a set-up capable of measuring the entanglement of signal and idler photons which is necessary to demonstrate a difference beam state has been produced. This set-up would use a direct detection system that measures both the frequency and arrival time of photon pairs. This would allow for the two photon amplitude to be calculated and the Schmidt number to be determined.
A second aim of this project was to produce a quantum nonlinear interferometer using two nonlinear crystals. I provide a theoretical description of the output of a single-cycle quantum nonlinear interferometer composed of two aperiodically poled lithium niobate crystals, for the first time to our knowledge. I build this interferometer, observing nonlinear interference which is modified using a 4mm thick BK7 sample. A broadband phase measurement was determined from this measurement with a bandwidth of 20nm. This provides an important step towards carrying out a broadband homodyne measurement and thus quantifying the squeezing of the light produced by these crystals. This would allow the crystals to be used in an interferometer that beats the standard quantum noise limit
Enhancing and personalising endometriosis care with causal machine learning
Get PDFFunding: Bowles is partially supported by the Austrian Funding Council (FWF) under Meitner M 3338-N.Endometriosis poses significant challenges in diagnosis and management due to the wide range of varied symptoms and systemic implications. Integrating machine learning into healthcare screening processes can significantly enhance and optimise resource allocation and diagnostic efficiency, and facilitate more tailored and personalised treatment plans. This paper discusses the potential of leveraging patient-reported symptom data through causal machine learning to advance endometriosis care and reduce the lengthy diagnostic delays associated with this condition. The goal is to propose a novel personalised non-invasive diagnostic approach that understands the underlying causes of patient symptoms and combines health records and other factors to enhance prediction accuracy, providing an approach that can be utilised globally
The genome sequence of the particolored bat, Vespertilio murinus Linnaeus, 1758
Get PDFFunding: This work was supported by Wellcome through core funding to the Wellcome Sanger Institute [206194, https://doi.org/10.35802/206194] and the Darwin Tree of Life Discretionary Award [218328, https://doi.org/10.35802/218328 ]. SCV was supported by a UKRI Future Leaders Fellowship (MR/T021985/1) and an ERC Consolidator Grant (101001702; BATSPEAK). ECT is supported by Irish Research Council Laureate Award IRCLA/2017/58 and Science Foundation Ireland Future Frontiers 19/FFP/6790.We present a genome assembly from an individual male Vespertilio murinus (the particolored bat; Chordata; Mammalia; Chiroptera; Vespertilionidae). The genome sequence is 1,925.6 megabases in span. Most of the assembly is scaffolded into 20 chromosomal pseudomolecules, including the X and Y sex chromosomes. The mitochondrial genome has also been assembled and is 16.96 kilobases in length.Peer reviewe
Spatial proteomics identifies a CRTC-dependent viral signaling pathway that stimulates production of interleukin-11
Get PDFFunding: This work was supported by a Medical Research Council project grant (MR/W025647/1) to M.P.W., an Addenbrooke’s Charitable Trust grant (900408) to M.P.W., an Evelyn Trust fellowship (project reference 18/27) to B.J.R., an Evelyn Trust grant (20/75) to P.A.L., a Medical Research Council fellowship and BBSRC project grants to B.C. (MR/R021821/1, BB/X001261/1, BB/V017780/1, and BB/V006096/1), and the NIHR Cambridge Biomedical Research Centre (NIHR203312). G.H.H.B. was supported by the Max Planck Society for the Advancement of Science.Appropriate cellular recognition of viruses is essential for the generation of an effective innate and adaptive immune response. Viral sensors and their downstream signaling components thus provide a crucial first line of host defense. Many of them exhibit subcellular relocalization upon activation, resulting in the expression of interferon and antiviral genes. To comprehensively identify signaling factors, we analyzed protein relocalization on a global scale during viral infection. cAMP-responsive element-binding protein (CREB)-regulated transcription coactivators 2 and 3 (CRTC2/3) exhibited early cytoplasmic-to-nuclear translocation upon infection with multiple viruses in diverse cell types. This movement was dependent on mitochondrial antiviral signaling protein (MAVS), cyclo-oxygenase proteins, and protein kinase A. A key effect of CRTC2/3 translocation is transcription of the fibro-inflammatory cytokine interleukin (IL)-11. This may be important clinically in viral infections associated with fibrosis, including SARS-CoV-2. Nuclear translocation of CRTC2/3 is, therefore, identified as an important pathway in the context of viral infection.Peer reviewe
Health decline and residential transitions among older adults in Europe
Get PDFFunding: Sanny Afable was supported by a St Andrews–Max Planck PhD Studentship in Population Health. He is also grateful for the support from the International Max Planck Research School for Population Health and Data Science (IMPRS-PHDS). Research by Sanny D. Afable, Hill Kulu and Júlia Mikolai was also supported by the ESRC Centre for Population Change Connecting Generations research programme (Grant ES/W002116/1). Mikko Myrskylä was supported by the Strategic Research Council (SRC), FLUX consortium, decision numbers 345130 and 345131; by the National Institute on Aging (R01AG075208); by grants to the Max Planck–University of Helsinki Center from the Max Planck Society (Decision number 5714240218), Jane and Aatos Erkko Foundation, Faculty of Social Sciences at the University of Helsinki and Cities of Helsinki, Vantaa and Espoo; and the European Union (ERC Synergy, BIOSFER, 101071773).Residential mobility is a possible strategy to cope with health challenges in later life. However, little research has examined whether and how health decline triggers residential mobility and whether this relationship differs between parents and childless individuals. Using data on parents and non-parents aged 50+ from the Survey of Health, Ageing and Retirement in Europe (SHARE), we perform multinomial logistic regression to examine how recent and previous health events (defined as a decline in acute health, functional limitation, frailty and self-rated health) influence the 2-year probability of transitions between care arrangements. We find that recent and previous health declines are not triggering moves towards intergenerational co-residence, but acute health events, functional limitation and worsened frailty are associated with transitions to home-based care for parents and non-parents alike. Additionally, previous health declines have a stronger influence on most residential transitions compared to recent health declines across parental status, suggesting that it takes time for health decline to induce residential mobility. Our findings demonstrate the importance of viewing late-life residential mobility from a relational framework and highlight home-based care as a key strategy for responding to health challenges in later life.Peer reviewe
Quantifying stratospheric biases and identifying their potential sources in subseasonal forecast systems
Get PDFFunding: The work of Rachel W.-Y. Wu is funded through ETH grant ETH-05 19-1. Support from the Swiss National Science Foundation through projects PP00P2_170523 and PP00P2_198896 to Daniela I. V. Domeisen is gratefully acknowledged. Chaim I. Garfinkel and Chen Schwartz are supported by the ISF–NSFC joint research program (grant no. 3259/19). The work of Marisol Osman was supported by UBACyT20020170100428BA and PICT-2018-03046 projects. The work of Alvaro de la Cámara is funded by the Spanish Ministry of Science and Innovation through project PID2019-109107GB-I00. Blanca Ayarzagüena and Natalia Calvo acknowledge the support of the Spanish Ministry of Science and Innovation through the JeDiS (RTI2018-096402-B-I00) project. Froila M. Palmeiro and Javier García-Serrano have been partially supported by the Spanish ATLANTE project (PID2019-110234RB-C21) and Ramón y Cajal program (RYC-2016-21181), respectively. Neil P. Hindley and Corwin J. Wright are supported by UK Natural Environment Research Council (NERC), grant number NE/S00985X/1. Corwin J. Wright is also supported by a Royal Society University Research Fellowship UF160545. Seok-Woo Son and Hera Kim are supported by the Basic Science Research Program through the National Research Foundation of Korea (2017R1E1A1A01074889). his material is based upon work supported by the US Department of Energy, Office of Science, Office of Biological and Environmental Research (BER), Regional and Global Model Analysis (RGMA) component of the Earth and Environmental System Modeling program under award no. DE-SC0022070 and National Science Foundation (NSF) IA 1947282. This work was also supported by the National Center for Atmospheric Research (NCAR), which is a major facility sponsored by the NSF under cooperative agreement no. 1852977. Pu Lin is supported by award NA18OAR4320123 from the National Oceanic and Atmospheric Administration (NOAA), U.S. Department of Commerce. Zachary D. Lawrence was partially supported under NOAA award NA20NWS4680051; Zachary D. Lawrence and Judith Perlwitz also acknowledge support from US federally appropriated funds.The stratosphere can be a source of predictability for surface weather on timescales of several weeks to months. However, the potential predictive skill gained from stratospheric variability can be limited by biases in the representation of stratospheric processes and the coupling of the stratosphere with surface climate in forecast systems. This study provides a first systematic identification of model biases in the stratosphere across a wide range of subseasonal forecast systems. It is found that many of the forecast systems considered exhibit warm global-mean temperature biases from the lower to middle stratosphere, too strong/cold wintertime polar vortices, and too cold extratropical upper-troposphere/lower-stratosphere regions. Furthermore, tropical stratospheric anomalies associated with the Quasi-Biennial Oscillation tend to decay toward each system's climatology with lead time. In the Northern Hemisphere (NH), most systems do not capture the seasonal cycle of extreme-vortex-event probabilities, with an underestimation of sudden stratospheric warming events and an overestimation of strong vortex events in January. In the Southern Hemisphere (SH), springtime interannual variability in the polar vortex is generally underestimated, but the timing of the final breakdown of the polar vortex often happens too early in many of the prediction systems. These stratospheric biases tend to be considerably worse in systems with lower model lid heights. In both hemispheres, most systems with low-top atmospheric models also consistently underestimate the upward wave driving that affects the strength of the stratospheric polar vortex. We expect that the biases identified here will help guide model development for subseasonal-to-seasonal forecast systems and further our understanding of the role of the stratosphere in predictive skill in the troposphere.Peer reviewe
Towards human-level deep robotic cloth manipulation using vision-based methods with implicit representations
No full textThis PhD study investigates the application of learning-based neural controllers to cloth-shaping tasks, including flattening and folding fabrics, T-shirts, and other garment types. We constrain our problem to a single-gripper Pick-and-Place (PnP) action output, using a top-down RGB-D camera as the observation input. We explore both Deep Reinforcement Learning (DRL) and Deep Imitation Learning (DIL) algorithms that learn implicit latent representations and do not require explicit intermediate feature extraction.
In general, we developed the proposed controllers in this PhD study initially in simulation, and subsequently proposed a series of Simulation-to-Reality (Sim2Real) techniques for real-world deployment. We first investigated DRL algorithms for square-fabric flattening in simulation. We then explored DIL methods to perform towel folding from both flattened and crumpled initial states. Following this, we compared and contrasted all the developed controllers from this PhD in the real world on two different robotic platforms using our proposed real-world deployment framework for cloth manipulation. Lastly, we extended our study to more complex garment types, such as T-shirts, trousers, skirts, and dresses. We successfully demonstrate that a single goal-conditioned model-based Deep Reinforcement Learning (DRL) method can flatten all four garments in simulation, and it can flatten a long-sleeve T-shirt in our real-robot setup. In addition, we developed a general Python framework for benchmarking various types of control algorithms on many different simulation and real-world environments to facilitate our research.
We advance the State-of-The-Art (SoTA) performance of vision-based neural controllers in the investigated domain. Our research outcomes demonstrate that action diversity, pick-position precision, specialised reward engineering, and high-quality expert demonstrations are keys to the success of these general data-driven controllers. However, our research also indicates that robotic control of cloth-shaping still cannot reach human-level manipulation capabilities, which continues to support the Moravec paradox in robotic control. In the future, we intend to integrate implicit topological structure learning for improved performance and to extend these methods to other action primitives
Tidal flow masks acoustic detections of harbour porpoises (Phocoena phocoena) : implications for passive acoustic studies of cetaceans
Get PDFFunding: This work was undertaken as part of the SEACAMS2 project, part-funded by the European Regional Development Fund through the Welsh Government.Passive acoustics is widely used to detect vocalising cetaceans, yet in tidal environments, strong currents facilitate sediment transport, creating “flow noise” that may mask signals and bias detection ranges. Although detection ranges are known to vary with background noise, the magnitude and spatiotemporal scale of such variation in tidal environments remain poorly quantified. Flow noise may fluctuate within tidal cycles and across small spatial scales, with consequences for estimating cetacean occurrence. To examine this, we tested the effects of flow noise on harbour porpoise (Phocoena phocoena) echolocation click detection, from data collected from an array of moored recorders in a tidal stream environment. Flow noise overlapping with porpoise clicks varied by up to 29 dB in mean sound pressure levels within tidal cycles (∼12 h). Differences between sites <500 m apart were also significant, and modelled relationships between porpoise occurrence and tidal flow speed changed when a fixed detection threshold was applied. These findings show that flow noise in tidal habitats is heterogeneous across space and time, which may bias estimates of cetacean occurrence and distribution. Accounting for flow noise is therefore essential in ecological studies and is particularly relevant in environmental assessments of tidal energy developments.Peer reviewe
Linking genetics, biomechanics, life-history, and behaviour to understand rapid animal signal evolution
No full textAcoustic signals are essential in mate choice and speciation, so understanding factors that promote acoustic divergence will broaden our knowledge of animal signal evolution and the origin of new species. However, signal diversification is expected to be constrained by morphology and biomechanics of sound-producing structures, as well as counter-selection by pre-existing receiver preferences, making early-stage signal diversification extremely rare in nature. In this thesis, I use a rapidly-evolving field cricket, Teleogryllus oceanicus, as a model to investigate how new signal variants emerge and spread. In Hawaii, male mating songs attract both conspecific females and an eavesdropping parasitoid fly, Ormia ochracea, which locates males’ signals and kills them. Under the strong fly selective pressure, acoustic signals of male crickets have been disrupted via genetically-encoded wing polymorphisms, and multiple adaptive male morphs have evolved independently within ca. 20 years (‘flatwing’ and ‘curly-wing’ lost the ability to sing and ‘small-wing’ shifted to different signal values). I investigated the behavioural, bioacoustic, morphological, biomechanical, genetic, genomic, and transcriptomic bases of rapid signal change among these novel morphs. The results firstly indicate how divergent use of alternative mating tactics between these convergent, silent male morphs may enable their co-existence in nature. Next, I characterised the biomechanical basis of rapid sexual signal diversification in small-wing males and determined that it was facilitated by permissive female preferences, which challenges longstanding theory about signal-receiver coevolution. I then tested how these novel signal variants escaped from loss due to drift or counter-selection, finding that the small-wing variant co-opts a pre-existing life-history trade-off that provides additional fitness benefits to both sexes without paying extra costs. As a result, novel signal variants are shielded from extinction. My findings highlight that positive trait covariance involving novel mutations under selection may represent an underappreciated mechanism driving rapid evolution."This work was supported by:
China Scholarship Council – University of St Andrews PhD scholarship [grant number 202004910423].
Natural Environment Research Council [grant numbers NE/W001616/1, NE/ T000619/1].
The Theodore J. Cohn Research Fund.
University of St Andrews (School of Biology)."--Fundin
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