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Optimisation of a P3 phase with superior high voltage reversibility
No full textFunding: This work was supported by the Faraday Institution (grant number FIRG018). The authors gratefully acknowledge support from the Engineering and Physical Sciences Research Council (EPSRC) Light Element Facility Grants EP/L017008/1, EP/ R023751/1 and EP/T019298/1 for funding the acquisition of the scanning electron microscopes and Raman spectrometer. R. A. H. acknowledges the Royal Academy of Engineering for Research Fellowship funding. Y. C. and D. O. S. are grateful to the Faraday Institution for funding the MICHAEL computing cluster hosted at University College London (UCL), FIRG019.Activation of oxygen anion redox represents an effective method of increasing the specific capacity as well as raising the operating voltage of layered sodium transition metal oxides. However, these reactions are often accompanied by irreversible structural transformations and detrimental side-reactions between the electrolyte and electrode interface which accelerate degradation, thereby impeding their practical application. To optimise the oxygen anion reversibility for practical use and compare the effects of dopants, we investigated Zn- and Ti-substitution both separately and combined in P3-structure Na0.7Mn0.75Ni0.25O2, assisted by DFT calculations. The Zn-substituted materials, Na0.7Mn0.65Ni0.25Zn0.1O2 and Na0.7Mn0.58Ni0.25Zn0.07Ti0.1O2 present superior cycling stability over the high voltage range 3.8–4.3 V and enhanced rate capability, delivering a reversible capacity of ∼80 mA h g−1 at 500 mA g−1 over the voltage window 2.2–4.3 V compared with 58.6 mA h g−1 for the parent-phase. The improved electrochemical performance of the Zn-substituted materials is attributed to suppression of the P3 to O′3 phase transformation revealed by X-ray diffraction and the lower electronegativity and filled d-band of Zn. The presence of TiO6 octahedra in the Ti-substituted materials relieves structural distortions/TM ordering, also improving the cycling stability. With Zn/Ti co-substitution these advantages may be combined, as demonstrated by the superior electrochemical performance observed for Na0.7Mn0.58Ni0.25Zn0.07Ti0.1O2.Peer reviewe
Profit shifting from Nigeria to Europe : the impact on human rights
Get PDFFunding: Funding from this work comes from the Scottish Funding Council International Science Partnership Fund 2023-24 (SFC / AN/21/2023) and Prof Sonia Buist Global Child Health Research Fund. BOH received both awards.The United Nations Universal Declaration of Human Rights states that everyone is entitled to economic and social rights essential to survive and thrive (Articles 25 and 26) and everyone is entitled to a social and international order in which their rights and freedom can be realised (Article 28). These rights must be ensured through national efforts and international cooperation (Article 22), but many millions of people worldwide do not access their rights, including the right to clean drinking water, safe sanitation, healthcare, and education. Government revenue from taxes plays a crucial role in ensuring these rights. However, globally, 10% of corporate tax revenue is lost because multinational corporations shift their profits from where they operate. This study examines the impact of profit shifting on tax revenue in Nigeria, focussing on access to economic and social rights and governance. It estimates the impact of revenue gains made on profits shifted from Nigeria to European tax havens, using data on profits shifted published by Wier and Zucman in 2022 and the Government Revenue and Development Estimations (GRADE) model for the estimations. The findings reveal that if the Nigerian government had additional revenue equivalent to tax losses, an additional 500,000 Nigerians would have their right to drink clean water and nearly 800,000 their right to use basic sanitation each day, 150,000 children would have their right to education, and 11 children would have their right to survive each day (amounting to 4,063 children each year). Increased revenue would also improve governance. In contrast, the gains European tax havens make as destinations for shifted profits in terms of rights are almost negligible, given that almost all Europeans have those economic and social rights discussed in this paper fulfilled. The tax reforms championed by the Organisation for Economic Co-operation and Development (OECD), including 27 European member nations, to tackle aggressive corporate tax avoidance and tax evasion—in short, tax abuse—fall short of ensuring a suitable international order for rights to be achieved. To remedy this, all European countries must support negotiations on international tax cooperation at the United Nations. This should include reforms on regulating multinational corporations, particularly through unitary taxation with formulary apportionment. In the short- and medium-term, interim measures to mitigate the harmful impacts of profit shifting are necessary. Countries must take steps to raise the global minimum corporate tax rate, introduce unilateral measures to tax multinational corporations, improve tax transparency and information sharing with lower-income countries, and strengthen anti-avoidance rules.Peer reviewe
The LSE right on Scruton's right : Kenneth Minogue on Roger Scruton's conservatism
Get PDFThis paper explores the intricate dynamics within postwar British intellectual conservatism, focusing on the critique posed by Kenneth Minogue against Roger Scruton’s conservative philosophy. Roger Scruton noted the fragmentation and marginalization of conservatism in postwar British intellectual circles, attributing it to the pervasive influence of John Stuart Mill’s skepticism toward conservative intellect. Despite this, notable conservative clusters emerged at the London School of Economics under Michael Oakeshott and at Peterhouse College, Cambridge, under Maurice Cowling. These clusters, identified as the LSE Right and the Peterhouse Right, respectively, significantly influenced political and academic discourses despite their small size. This paper examines the significant yet underexplored differences between Minogue, representing the LSE Right, and Scruton, the leading figure of Scruton’s Right. Drawing on Minogue’s personal papers, this study elucidates his critical stance on Scruton’s conservatism. By analyzing Minogue’s critique, this paper contributes to a deeper understanding of the doctrinal divergences within British conservatism and their implications for its future trajectory.Peer reviewe
A machine learning-based approach to quantify ENSO sources of predictability
Get PDFFunding: IC was funded by the John Fell Oxford University Press Research Fund and HC by NERC (NE/P018238/1).A machine learning method is used to identify sources of long-term ENSO predictability in the ocean (sea surface temperature (SST) and heat content) and the atmosphere (near-surface zonal wind (U10)). Tropical SST represents the primary source of predictability skill. While U10 does not increase the skill when associated with SST, our analysis suggests U10 alone has apredictive skill comparable to that of SST between 11 and 21 months in advance, from late fall up to late spring. The long-lead signal originates from coupled wind-SST interactions across the Indian Ocean (IO) and propagates across the Pacific via an atmospheric bridge mechanism. A linear correlation analysis supports this mechanism, suggesting a precursor link between anomalies in SST in the western and wind in the eastern IO. Our results have important implications for ENSO predictions beyond 1 year ahead and identify the key role of U10 over the IO.Peer reviewe
Duration and intensity of the late Permian (early Wuchiapingian) cool climate episode : sclerochemical evidence from brachiopod assemblages in Iran
Get PDFFunding: This work was supported by the MURST PRIN 2017RX9XXXY, project “Biota resilience to global change: biomineralization of planktic and benthic calcifiers in the past, present and future” to Prof. E. Erba and by the European Union – Next Generation EU PRIN MUR 2022WEZR44 to Prof. C. Bottini. M.V. was supported by the SPI scholarship 2022 by the Società Paleontologica Italiana (SPI). The work was also partly supported by the Italian Ministry for Universities and Research (MUR) through the project “Dipartimenti di Eccellenza 2023-27” (MV, GC, GDP, CB and LA). H.J. acknowledges funding from the Leverhulme Trust Early Career Fellowship (ECF-2023-199).The Permian period witnessed some of the most dramatic environmental and climate changes in Earth's history. In this paper, we focused on the cool climate episode that occurred during the early Wuchiapingian (Lopingian), which was possibly triggered by CO2 drawdown linked to weathering of the Emeishan LIP in South China. To unravel the duration and magnitude of this climate episode, we analysed brachiopod shells of Araxilevis intermedius (Abich, 1878) from correlatable Upper Permian beds in the Julfa and Abadeh sections of North and Central Iran, deposited near to the palaeoequator. After a multidisciplinary diagenetic screening involving petrography, CL, SEM, EBSD, elemental and isotopic analyses, the stable isotope sclerochemistry was studied in well-preserved shells, to investigate seasonal variations in δ18O and δ13C. At the base of both sections (Clarkina asymmetrica Zone), shells of A. intermedius recorded a high amplitude of temperature seasonality (∼6 °C) indicating the onset of the early Wuchiapingian cooling episode. Temperature seasonality decreased upwards (∼3.2 °C) and returned close to the seasonal temperature variation observed at comparable modern latitudes. The inferred seasonality pattern allowed us to constrain the end of the Wuchiapingian cooling phase to ∼257 Ma, at the top of the Clarkina guangyuanensis Zone. We found that the early Wuchiapingian cooling episode was short-lived, lasting about 2 Myr, supporting previous reports from South China. Based on δ13C results and biodiversity curves, we concluded that, despite witnessing variations in productivity and food supply, brachiopod assemblages showed high ecological resilience and did not undergo a major change in biodiversity.Peer reviewe
Timbre-texture co-ordinate : (a portfolio of original compositions)
Get PDFThe emergence and rapid development of innovative and revolutionary directions of avant-garde music in Europe during the twentieth century posed new problems and opportunities to composers, musicologists and performers. In some central movements and styles of the avant-garde it became impossible to find any traces of established forms of a melody or conventional rhythmic structures, and more and more works obeyed rules and aesthetics that went far beyond the existing paradigm of classical music of previous centuries.
The timbral-textural dimension became one of the foremost driving forces behind the architectonics of avant-garde music. This doctoral thesis researches and presents the theoretical formulation and practical implementation of the phenomenon of the timbre-texture co-ordinate, as well as being an introduction and study of the phenomenon of timbre-texture. This work formulates the theoretical definition and framework and also demonstrates its role within the structure of new music works written for diverse instrumentations ranging from solo instrument to chamber ensemble and orchestral symphony to opera and theatre. The author deals with music where there is no melody, harmony or rhythms in the traditional sense, and thus timbre-texture becomes the main instrument of developing and creating a new piece of music.
The research presents an innovative paradigm for composition, analysis and performance where timbre-texture is the fundamental dimension. It provides specific, rigorous and detailed demonstrations of ways of composing, analysing and performing avant-garde music with extensive use of new composition techniques and extended methods of playing instruments
Behavioural adaptations of beaked whales
No full textAbstract redacted"This work was supported by the U.S. Office of Naval Research [grant number N000141512553]; and funding from the MASTS pooling initiative (The Marine Alliance for Science and Technology for Scotland) and their support is gratefully acknowledged. MASTS is funded by the Scottish Funding Council [grant reference HR09011] and contributing institutions."--Fundin
Exponential asymptotics and higher-order Stokes phenomenon in singularly perturbed ODEs
Get PDFFunding: PHT is supported by the EPSRC grant EP/V012479/1. JS is supported by the EPSRC grant EP/W522491/1. This work was supported by EPSRC grant EP/R014604/1.The higher-order Stokes phenomenon can emerge in the asymptotic analysis of many problems governed by singular perturbations. Indeed, over the last two decades, the phenomenon has appeared in many physical applications, from acoustic and optical wave phenomena and gravity-capillary ripples to models of crystal growth and equatorial Kelvin waves. It emerges in a generic fashion in the exponential asymptotics of higher-order ordinary and partial differential equations. The intention of this work is to highlight its importance, and develop further practical methodologies for the study of higher-order Stokes phenomena, primarily for general nonintegrable problems. Our formal methodology is demonstrated through application to a second-order linear inhomogeneous ODE that exemplifies the simplest example of higher-order Stokes phenomena. In this model problem, the Borel transform can be derived explicitly, and this gives insight into the beyond-all-orders structure. We review and study additional examples, with physically important connections, including higher-order ODEs and eigenvalue problems.Peer reviewe
The importance of comorbidities at baseline and 5-Year follow-up in a lung cancer biomarker screening trial
Get PDFFunding: This research was part of the Vacational Scholarship Scheme at the University of St. Andrews funded by The Melville Trust for the Care and Cure of Cancer.Background/Objectives: Despite recent lung cancer screening (LCS) studies proving significant mortality reduction, comorbidities are a prominent issue affecting cost effectiveness, which is holding back national implementation. Incidental findings (IFs) of comorbidities make a significant contribution to delayed diagnoses and raise discussions about optimal management plans. This is particularly relevant to national lung cancer screening (NLCS), as the high-risk population qualifying for the screening often have increased likelihood for comorbidities due to their smoking history. Methods: The Early Detection of Cancer of the Lung Scotland (ECLS) (ClinicalTrials.gov identifier NCT01925625) study showcases a targeted approach to NLCS by implementing the blood-based biomarker EarlyCDT-Lung test. Firstly, this paper explored the ECLS dataset for comorbidities present within the screening population at baseline A chi-square analysis was then undertaken to investigate the relationship of cohort allocation and incidence of new comorbidities over the five-year follow-up period. Results: High prevalence conditions were cardiovascular (38.5%), neurological/psychiatric (33.9%), gastrointestinal (29.8%), and respiratory (19.2%). While 20.3% of the total patient cohort showed a newly discovered comorbidity, there was no significant variation in new incidences between the intervention and control cohort. Conclusions: When considering these results alongside the all-cause mortality reduction shown in previous analyses, they indicate that this targeted approach to LCS might help improve the benefit–harm ratio through the introduction of biomarkers. Further refining selection criteria for low-dose CT screening might contribute to minimising the risk of overdiagnosis and overtreatment.Peer reviewe
Future changes in the influence of the NAO on Mediterranean winter precipitation extremes in the EC-Earth3 large ensemble : the prominent role of internal variability
Get PDFFunding: MAB acknowledges support from the Natural Environment Research Council (NE/N006038/1).One of the largest uncertainties in future climate projections is the interplay between internally generated and externally forced changes. This study investigates the changes in the link between the North Atlantic Oscillation (NAO) and Mediterranean winter extreme rainfall and dry days by the end of the 21st century compared to present day. We compare two different future pathways and estimate the extent to which the NAO imprint is affected by the global warming level using the latest EC-Earth3 large ensemble historical and future experiments. It is shown that the expected range of winter extremes changes due to internal and unpredictable fluctuations of the NAO largely overcomes the signal associated with externally-forced NAO variations. The NAO is found to exert a similar control on European climate variability, regardless of the amount of warming. For most of the Mediterranean region, magnitude and even sign of projected changes in the NAO-congruent precipitation indices vary substantially across the individual ensemble members according to the corresponding evolution of the NAO. Internal variability provides an average basin-wide contribution of up to 90% or more to the total NAO-driven variability in SSP1–1.9, and of about 80% in SSP5–8.5. Sub-regionally, the anthropogenic component of the NAO link is more evident over the Iberian Peninsula and parts of the central Mediterranean. This emphasises the role of internal variability and related uncertainty in determining the future impact of the NAO via the large spread in the circulation responses. However, the NAO is found to exert a weaker influence on the extreme precipitation total variability in both future scenarios given their future marked increase in total intensity and variance as opposed to the negligible NAO-related trends. Opposite conclusions are drawn for dry days, which are projected to decrease in the future, especially in the northern Mediterranean. Thus, this study also highlights how the variability of future extreme precipitation intensity in the Mediterranean basin will be less dependent on the principal mode of internal climate variability, posing further challenges for prediction and adaptation to weather-related hazards.Peer reviewe
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