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Synthesis, characterisation and reactivity of group 2 complexes with a thiopyridyl scorpionate ligand
Get PDFFunding: The authors thank the University of Leicester and the College of Life Science and Engineering for a PhD scholarship (M. P. S.), Royal Society (RGS\R2\202097) and Engineering and Physical Sciences Research Council (EP/W00691X/1 and EP/T019867/1) for funding. X-ray diffraction at Leicester was also supported by the Engineering and Physical Sciences Research Council (EP/V034766/1).Herein we report the reactivity of the proligand tris(2-pyridylthio)methane (HTptm) with various Alkaline Earth (AE) reagents: (1) dialkylmagnesium reagents and (2) AE bis-amides (AE = Mg-Ba). Heteroleptic complexes of general formulae [Mg(Tptm)(R)] (R = Me, nBu; Tptm = {C(S-C5H4N)3}−) and [AE(Tptm)(N′′)] (AE = Mg-Ba; N′′ = {N(SiMe3)2}−) were targeted from the reaction of HTptm with R2Mg or [AE(N′′)2]2. Reaction of the proligand with dialkylmagnesium reagents led to formation of [{Mg(κ3C,N,N-C{Bu}{S-C5H4N}2)(μ-S-C5H4N)}2] ( 1 ) and [{Mg(κ3C,N,N-C{Me}{S-C5H4N}2)(μ-OSiMe3)}2] ( 2 ) respectively, as a result of a novel transfer of an alkyl group onto the methanide carbon with concomitant C-S bond cleavage. However, reactivity of bis-amide precursors for Mg and Ca did afford the target species [AE(Tptm)(N′′)] ( 3-AE ; AE = Mg-Ca), although these proved susceptible to ligand degradation processes. DFT calculations show that alkyl transfer in the putative [Mg(Tptm)(nBu)] ( 1m′ ) system and amide transfer in 3-Ca is a facile process that induces C-S bond cleavage in the Tptm ligand. 3-Mg and 3-Ca were also tested as catalysts for the hydrophosphination of selected alkenes and alkynes, including the first example of mono-hydrophosphination of 4-ethynylpyridine which was achieved with high conversions and excellent regio- and stereochemical control.Peer reviewe
Testing the predictability of morphological evolution in contrasting thermal environments
Get PDFFunding: The study was funded by a Natural Environment Research Council Grant (NE/N016734/1) awarded to K.J.P., N.B.M., S.S.K., and J.L. S.S.K. was supported by a NERC Advanced Fellowship (NE/J019100/1) and a European Research Council Starting Grant (640004).Gaining the ability to predict population responses to climate change is a pressing concern. Using a “natural experiment,” we show that testing for divergent evolution in wild populations from contrasting thermal environments provides a powerful approach, and likely an enhanced predictive power for responses to climate change. Specifically, we used a unique study system in Iceland, where freshwater populations of threespine sticklebacks (Gasterosteus aculeatus) are found in waters warmed by geothermal activity, adjacent to populations in ambient-temperature water. We focused on morphological traits across six pairs from warm and cold habitats. We found that fish from warm habitats tended to have a deeper mid-body, a subterminally orientated jaw, steeper craniofacial profile, and deeper caudal region relative to fish from cold habitats. Our common garden experiment showed that most of these differences were heritable. Population age did not appear to influence the magnitude or type of thermal divergence, but similar types of divergence between thermal habitats were more prevalent across allopatric than sympatric population pairs. These findings suggest that morphological divergence in response to thermal habitat, despite being relatively complex and multivariate, are predictable to a degree. Our data also suggest that the potential for migration of individuals between different thermal habitats may enhance nonparallel evolution and reduce our ability to predict responses to climate change.Peer reviewe
Multiculturalism, laïcité, unity, and diversity : conceptualizing difference management within China's integration policy
Get PDFTerrorist incidents call for renewed attention to difference management. While countries adopt different integration policies, they share concerns about maintaining the political unity of the secular state in increasingly polarized societies in the post-9/11 context. This paper draws on the discussions of multiculturalism and laïcité to conceptualize the states’ approaches to difference management, with reference to the “diversity within unity” paradigm in China. It argues that China’s integration policy can be understood better within the framework of difference management and benefit from, and pluralize, the rich literature on this topic that focuses largely on Western experience.Peer reviewe
The Jacobite groundwork of James Steuart’s political economy
Get PDFIn the late 1740s and the 1750s the Jacobite exile James Steuart began to compose the work that became his Principles of Political Oeconomy. This article shows how the political principles of this work were shaped in two contexts neglected by earlier scholars: the networks that shaped Steuart’s formation as a Jacobite, and the debates about absolute monarchy that he encountered in France early during his exile starting in 1746. It demonstrates that Steuart’s vision of an economically active, interventionist state chiefly developed not from German debates about administration, as is often assumed, but from long-running Scottish currents of opposition to British government policy and radical French ideas about how monarchical reform can secure equal rights for all. This article thus uncovers the Jacobite and French origins of Steuart’s variety of interventionism, which troubled Adam Smith, inspired French revolutionaries, and influenced Hegel, Marx, and the broader history of political economy.Peer reviewe
Inhomogeneous terminators on the exoplanet WASP-39 b
Get PDFFunding: M.E.S. acknowledges support from the 51 Pegasi b Fellowship funded by the Heising–Simons Foundation.Transmission spectroscopy has been a workhorse technique used over the past two decades to constrain the physical and chemical properties of exoplanet atmospheres. One of its classical key assumptions is that the portion of the atmosphere it probes—the terminator region—is homogeneous. Several works from the past decade, however, have put this into question for highly irradiated, hot (Teq ≳ 1,000 K) gas giant exoplanets, both empirically and through three-dimensional modelling. While models have predicted clear differences between the evening (day-to-night) and morning (night-to-day) terminators, direct morning and evening transmission spectra in a wide wavelength range have not been reported for an exoplanet so far. Under the assumption of precise and accurate orbital parameters for the exoplanet WASP-39 b, here we report the detection of inhomogeneous terminators on WASP-39 b, which has allowed us to retrieve its morning and evening transmission spectra in the near-infrared (2–5 μm) using the James Webb Space Telescope. We have observed larger transit depths in the evening, which are, on average, 405 ± 88 ppm larger than the morning ones, and also have qualitatively larger features than the morning spectrum. The spectra are best explained by models in which the evening terminator is hotter than the morning terminator by 177−57+65 K, with both terminators having C/O ratios consistent with solar. General circulation models predict temperature diferences broadly consistent with the above value and point towards a cloudy morning terminator and a clearer evening terminatorPeer reviewe
Selected works in analytic theology
No full textTable of Contents: 1. The Hiddenness of God (2018, book published by Oxford University Press) 2. “Polytheism and Christian Belief” (2006, published in Journal of Theological Studies) 3. “The Metaphysics of Original Sin” (2007, published in Persons: Human and Divine, edited by Dean Zimmerman and Peter van Inwagen) 4. “Theology without Idolatry or Violence” (2015, published in Scottish Journal of Theology) 5. “Gender as a Divine Attribute” (2016, published in Religious Studies) 6. “Worship, Protest, and the Deformation of Prayer,” (2020, published in Essays in Analytic Theology, vol. 2, by Michael Rea
From portraits of absence to analogies of resurrection : a theological engagement with photographic phenomenology
Get PDFRedacted version excludes images for which permission has not been granted by the rights holderWhile Christian theologians have considered in some depth more established forms of artistic expression (e.g., painting, sculpture, theatre), with only a few notable exceptions very little theological attention has been paid to photography. This is despite the medium’s rapid growth and its social and political importance. In this thesis I begin to address that gap by exploring photographic phenomenology from a theological perspective. I demonstrate that photography can be put to a diverse range of religious uses, and touch on ways in which photographs can be of benefit in contexts of preaching and teaching, pastoral care, and mission. The bulk of this thesis explores possible religious experiences and uses of photographs (uses that might engender religious experience, or mediate a sense of divine presence), but this exploration acknowledges that many of the experiences discussed may not be unique to those of a religious perspective. I propose, therefore, a spectrum of uses and experiences including the seemingly straightforward ‘illustrative or instructional’, the ‘anamnetic’, the ‘affective’ (or ‘sentimental’), and the ‘sacramental’.
This exploration arises from a critical engagement with the dominant photographic phenomenology of proof as presented by Roland Barthes from a theological perspective. From that engagement I pursue one of the experiences Barthes describes but later abandons, that ‘Photography has something to do with resurrection’. I argue that Barthes’ choice to abandon this experience was a mistake. My argument is developed cumulatively across three chapters in each of which I use a key challenge against photography to demonstrate the utility of a theologically engaged photographic phenomenology that extends Barthes’ suggested resurrection-like experience. The challenges discussed are first, that the photograph is always memento mori, secondly, that photographs of violence and suffering always demonstrate the complicity of the photographer and perpetuate the victim’s suffering, and finally, that photographs are sentimental objects. In a chapter that draws together the conclusions of the previous three, I propose a theologically informed methodology for reading photographs that is then applied in the final chapter to three case studies. I conclude the thesis with a reflection upon those case studies, identifying the particular theological functions they serve
Chiral selenium-integrated multi-resonant thermally activated delayed fluorescent emitters showing improved reverse intersystem crossing rate
Get PDFFunding: Jingxiang Wang thanks the China Scholarship Council (202006250026). This work was funded by the EPSRC through grant numbers EP/R00188X/1, EP/W007517/1, EP/W015137/1 and EP/Z535291/1. This project has been partly funded by the European Union Horizon 2021 research and innovation program under grant agreement no. 101073045 (TADFsolutions) and the EPSRC grant EP/X026175/1.Nitrogen/carbonyl (N/C═O) based multi-resonant thermally activated delayed fluorescence (MR-TADF) emitters are attractive due to their bright, narrowband emission and the ease with which they can be synthesized. However, their photophysics typically suffer from slow reverse intersystem crossing (RISC) because of their relatively large singlet-triplet energy gap (ΔEST). Thus, the organic light-emitting diodes (OLEDs) with these emitters typically show severe efficiency roll-off. Here, two MR-TADF emitters DiKTaSe and tBuCz-DiKTaSe have been designed and synthesized. The introduction of selenium in the form of an annelated benzoselenophene enhances spin-orbit coupling and increases the RISC rate. The twisted ortho-substituted tert-butylcarbazole moiety in tBuCz-DiKTaSe helps to suppress aggregation-caused quenching of the emission in films. In addition, the large size of the selenium atom and long C─Se bonds induce helical chirality in both DiKTaSe and tBuCz-DiKTaSe . Finally, the OLEDs with DiKTaSe showed maximum external quantum efficiency (EQEmax) of 22.7% while OLEDs with tBuCz-DiKTaSe showed a higher EQEmax of 27.8% and less-pronounced efficiency roll-off, with EQE at 100 cd m−2 (EQE100)/ EQE at 1000 cd m−2 (EQE1000) of 23.5/12.5%. These efficiency values are amongst the highest of devices employing DiKTa-based emitters. Our work provides key insight into how to judiciously employ heavy atoms to increase the performance of the emitter and the device.Peer reviewe
Beyond Pentelikon : imported white marbles in Athenian sculptural workshops of the Roman period
Get PDFFunding: Financial support was provided by a grant from the Boochever Endowment for Fieldwork and Scientific Analyses, administered by the Archaeological Institute of America, and a Franklin Research Grant from the American Philosophical Society. All photographs of Agora sculptures are provided by the Ephorate of Antiquities of Athens – Agora Excavations/American School of Classical Studies at Athens, © Hellenic Ministry of Culture/Organization of Cultural Resources and Development (H.O.C.RE.D.).This article presents the results of a provenance study of the marbles used for 58 sculptures from the excavations of the Athenian Agora (Greece), including numerous unfinished works. The sculptures were preselected for analysis because they did not match the visual characteristics of local Pentelic marble. All sculptures were studied noninvasively with a standard light source, and measurements of the Maximum Grain Size (MGS), the Most Frequent Grain Size (MFS), and translucency were taken. The sculptures were also analyzed for trace elements, such as strontium (Sr) and manganese (Mn), using a portable X-Ray Fluorescence (pXRF) instrument. Samples were collected from 44 sculptures for laboratory-based analyses, including verification measurements of MGS and MFS under a stereoscopic microscope, qualitative examination of crystalline features of the marbles, and Isotopic Ratio Mass Spectroscopy (IRMS) for measurements of the stable isotopes of carbon and oxygen. The results show that a range of imported white marbles were being carved in local Athenian workshops during the Roman period (1st century BCE to 3rd century CE), including marbles from Thasos (5 sculptures), Paros (as many as 16 sculptures), and Afyon, near Dokimeion in Phrygia (as many as 33 sculptures). Marble from Göktepe, near Aphrodisias in Caria, is also identified (3 or 4 sculptures), but it is present only among the finished works. This study highlights the extensive material networks to which ancient Athens belonged and underscores the importance of interdisciplinary methodologies, integrating archaeometry, archaeology, and art history, for reconstructing the artistic practices and aesthetic desires of past communities.Peer reviewe
Post COVID glaucoma service redesign utilising electronic patient triage and community optometry clinics (Fife, Scotland 2020—2022)
Get PDFFunding: Partial funding from the Scottish Government.Background COVID-19 caused a huge backlog of patients in glaucoma clinics. This study describes redesign of an entire glaucoma service with electronic patient triage to three levels and utilisation of the Scottish optometry infrastructure of upskilled optometrists. Methods 2276 patients in glaucoma clinics were identified and triaged to three levels in keeping with Glauc-strat-fast guidance with local amendments. Every patient detail was entered into a bespoke glaucoma database to include demographics, clinical findings and social deprivation scores. The database generated automatic patient, GP and optometrist letters. Level one patients (482) were discharged within the Scottish general optometry service contract. Level two patients (714) were discharged to glaucoma accredited community optometry clinics. The glaucoma consultants would discuss the optometry decision making through screen share once a week. Level three patients (1080) were retained in hospital. All outcomes were audited and analysed 24 months after the new service. Results Statistically significant parameters were found between the three groups, to include more normal eyes, less mean deviation on visual fields and less social deprivation in level one patients. After 24 months level one patients had a return rate of 40.2%, mainly for other diseases with only 20.4% retained within hospital or level two. 9.4% of level two patients returned to hospital with retention of only 2.7% in hospital at 24 months. Conclusion Glaucoma patients in Scotland can be appropriately triaged to glaucoma accredited community optometry clinics. This frees capacity within hospital to see patients with moderate and severe disease in a timely fashion, for best visual outcomes.Peer reviewe
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