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The Jacobite groundwork of James Steuart’s political economy
No full textIn 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
Shear heating during rapid subduction initiation beneath the Samail Ophiolite
No full textMetamorphic soles beneath ophiolites are thought to record subduction initiation. However, there is ambiguity about the tectonic and thermal mechanisms operative during subduction initiation, arising partly from uncertainty in the duration of sole metamorphism. Here we use chemical mapping and diffusion speedometry of garnet crystals from the metamorphic sole of the Samail Ophiolite (Oman and United Arab Emirates) to show that high-temperature (≥750 °C) metamorphism was rapid, lasting ≤1 Myr (potentially ≤100 kyr) at peak temperature conditions. The short durations are supported by zircon U–Pb ages and new garnet–whole-rock–zircon Lu–Hf data from the same rocks, contrasting with previous inferences for ≥8 Myr metamorphic durations. These observations are nominally consistent with the spontaneous sinking of a dense lower plate. However, the rapid metamorphic timescales cannot be accounted for solely by conductive thermal equilibration with juxtaposed oceanic mantle. One potential explanation is dissipative heating driven by relative motion across the nascent plate interface. This interpretation accounts for the timescales, the spatial pattern of metamorphism and the global similarities in sole pressure–temperature conditions independent of other geodynamic variables
Adverse experiences of women with undiagnosed ADHD and the invaluable role of diagnosis
No full textGirls and women are disproportionately affected by delayed diagnoses of attention-deficit/hyperactivity disorder (ADHD), but research on the impact of this is limited. Our study aimed to centre lived experiences of women with late-diagnosed ADHD to increase understanding of the impact of such delays. We employed a mixed methods survey to investigate the perspectives of 28 women with late-diagnosed ADHD. Results starkly demonstrate the criticism and lack of support participants faced from society and medical professionals, illustrating the negative consequences of delayed ADHD diagnosis on quality of life and mental health. Participants commonly reported internalising criticism and described disconcertingly low self-esteem; citing guilt, shame, and negative self-perception due to delayed diagnoses. Participants found diagnosis revelatory, their lives finally making sense; citing healing, improved self-esteem, and life feeling more worth living. The adversities faced from delayed diagnoses were described from early childhood, through adolescence, and adulthood. Participants reflected on ‘what could have been’, and described grieving the lives they could have led if diagnosed earlier. The negative impacts of missed ADHD diagnosis are broad and span life stages. With potential implications for public health policy, this work highlights the importance of increasing girls’ and women’s access to ADHD diagnoses to address avoidable detrimental hardship
Common mechanism of dual emission in linearly-linked donor-acceptor-type thermally activated delayed fluorescence molecules
No full textLinearly-linked donor–acceptor-type (D–A) thermally activated delayed fluorescence molecules have been expected to be used as efficient emitters in organic light emitting diodes. Despite their simple molecular structures, some of these molecules exhibit a complex dual emission mechanism due to their two conformers: quasi-coplanar (q-copl.) and perpendicular (perp.) conformers. We have investigated three molecules of this type: phenothiazine–triphenyltriazine, 9,9-dimethyl-9,10-dihydroacridine–triphenyltriazine, and phenoxazine–triphenyltriazine using picosecond time-resolved photoluminescence and femtosecond transient absorption spectroscopy measurements. We have revealed the dual emission mechanism common to the three molecules: after photoexcitation, in the q-copl. conformer, the second singlet excited state with local excitation character emits strong fluorescence, which decays in 3–7 ps as it relaxes to the lowest singlet excited state with charge transfer (CT) character. The CT state exhibits relatively weak fluorescence with a lifetime of tens to hundreds of picoseconds. In the perp. conformer, the excited state shows a pronounced CT character with a weaker oscillator strength reduced by two orders of magnitude, structural relaxation in about 4 ps and a slow decay in >1 ns. The dual emission intensity ratio is determined by the population ratio between the q-copl. and perp. conformers in the ground state. The difference in this intensity ratio between the three molecules is ascribed to the difference in relative energetic stability between the two conformers in the ground state. The emission mechanism common to the linearly-linked D–A molecules deepens the understanding of their photophysical properties and opens new pathways for the development of advanced photofunctional materials
Cycloadditions as a sweet route to ‘double C-glycosylation’
No full textPharmaceuticals, such as the antibiotic erythromycin, and sodium-dependent glucose transporter (SGLT1 & SGTL2) inhibitors such as Bexagliflozin (diabetes) and Sotagliflozin (heart disease), are often sugar-decorated (glycosylated). Glycosylation is a key component of the binding motif in SGLT inhibitors and in natural products, glycosylation often confers improved bioactivity and bioavailability. Whilst a single C-glycoside link between a sugar moiety and its aglycone core is a common feature in natural products isolated to date, only a small number, including the antibiotics granaticin and sarubicin, are covalently bonded twice to a single sugar moiety. The way in which this “double C-glycosylation” is naturally mediated is not yet known, yet speculated. Here we report the exploration and development of a potentially biomimetic procedure that utilises intermolecular cycloaddition chemistry to access new “double C-glycosylated” products and enables the creation of bridged polycyclic ethers from a common maltol derived oxidopyrylium salt precursor
Spatial capture-recapture can improve environmental impact assessments for large carnivores
No full text1. Environmental Impact Assessments (EIAs) for large carnivores frequently rely on summary statistics or relative abundance indices to evaluate the effects of infrastructure development on predator populations. However, these approaches often fail to account for imperfect detection and observer bias, which can result in misleading conclusions about population status and trends. This leads to potentially unreliable conclusions and suboptimal conservation decisions.2. This study addresses these limitations by demonstrating the benefits of spatial capture–recapture (SCR), particularly its capacity to account for detection probability and spatial heterogeneity, using the wolf (Canis lupus) as a model species in a 3-year monitoring programme within a windfarm-impacted landscape in Portugal.3. We show that, aside from the addition of georeferenced individual identification and survey effort data, implementing SCR requires only minimal adjustments to existing survey designs while yielding substantial analytical benefits. SCR generates unbiased estimates of density, abundance and space use—critical metrics for assessing population status—and allows the integration of spatial covariates (such as proximity to infrastructure) to enable explicit, model-based inference about potential impacts.4. Practical implications. Incorporating SCR into EIA monitoring can replace relative abundance indices with robust ecological metrics, enhancing transparency and reliability for stakeholders. This approach supports adaptive management procedures and the development of effective mitigation and compensation measures across project phases, ultimately promoting the long-term resilience of large carnivore populations
Why Elon Musk’s US$34 billion loss wasn’t really that – and what it tells us about the philanthropy of the ultra-wealthy
No full textIrredundant bases for soluble groups
No full textLet Δ be a finite set and G be a subgroup of Sym(Δ). An irredundant base for G is a sequence of points of Δ yielding a strictly descending chain of pointwise stabilisers, terminating with the trivial group. Suppose that G is primitive and soluble. We determine asymptotically tight bounds for the maximum length of an irredundant base for G. Moreover, we disprove a conjecture of Seress on the maximum length of an irredundant base constructed by the natural greedy algorithm, and prove Cameron's Greedy Conjecture for |G| odd