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Direct synthesis of polyesterether from ethylene glycol
Get PDFFunding: This research is funded by a UKRI Future Leaders Fellowship (MR/W007460/1) and an EPSRC grant (EP/Y005449/1).We report here a method for making polyesterether from ethylene glycol. The reaction is catalyzed by a ruthenium complex and liberates H2 gas and H2O as byproducts. Mechanistic studies conducted through experiments and DFT computations suggest that the chain growth of the polymerization process involves both dehydrogenation and dehydration pathways stemming from a hemiacetal intermediate, leading to the formation of esters and ethers, respectively. Investigations into the polymerization of other diols have also been conducted, showing that diols with a lower number of carbons between the alcohol groups (propylene glycol, glycerol, and 1,3-propanediol) lead to the formation of polyesterether whereas α,ω-diols containing a higher number of carbons (1,6-hexanediol and 1,10-decanediol) lead to the formation of polyester.Peer reviewe
Researching identity in the imposed boundaries of the nation-state : a meta-analytical review of identity and intergroup relations between Kurds and Turks
Get PDFWe conducted three meta-analyses on 28 studies examining the role of ethnic and national identity in outgroup attitudes, perception of discrimination against Kurds, and support for minority rights within the context of Turkish–Kurdish conflict (e.g., state oppression against Kurds and Kurdish resistance in Turkey). Results revealed a negative relationship between identity and outgroup attitudes. The role of identity in perceived discrimination and support for minority rights was inconsistent and mostly dependent on ethnic group status. We found a negative relationship between identity and perceived discrimination against Kurds among Turks and a positive relationship among Kurds. Additionally, there was a negative relationship between Turkish identity and support for minority rights, while the relationship among Kurds was not significant. Overall, our study demonstrates that intergroup relations in this context are far more complex (and different from others) than often assumed, and it can be harmful to presume symmetrical associations across different groups.Peer reviewe
Book symposium on Jessica Brown, Groups as epistemic and moral agents, Oxford: OUP, 2024--précis and replies to contributors
Get PDFI provide a précis of my book, Groups as Epistemic and Moral Agents (Oxford: 2024) before moving on to discuss the various contributions to the symposium.Peer reviewe
Artificial worlds and artificial minds : authenticity and language learning in digital lifeworlds
Get PDFLanguage learning is increasingly being extended into digital and online spaces that have been enhanced by simulated reality and augmented with data and artificial intelligence. While this may expand opportunities for language learning, some critics argue that digital spaces may represent a pastiche or a parody of reality. However, while there are genuine issues, such criticisms may often fall back on naïve or essentialist views of authenticity, in particular by narrowing language learning scenarios to real-life or genuine communication. I argue that research undersocialises authenticity by not taking social relations into sufficient consideration, which denies or elides the ways that authenticity is achieved. In this conceptual paper, I offer a relational account of authenticity, where I conceive digital environments within a stratified ontological framework, where authenticity is not inherent in individuals or texts, but instead emerges from complex social contexts. Authenticity, then, does not refer to authenticity of texts or “being oneself”, but authenticity in relation to others. A stratified ontology provides opportunities to extend relations with others, offering what is described as a “submersion into a temporary agency”, where language learners can experiment with the social order in order to achieve authenticity of themselves in the target language. Finally, I present a relational pedagogy based on responsiveness, where feedback is distributed among disparate human and technical actors which facilitate, problematise or endorse authenticity.Peer reviewe
Humans may not have a uniquely enhanced sequence memory : sequence discrimination is facilitated by causal-logical framing in humans and chimpanzees
Get PDFFunding. This project has received funding from the John Templeton Foundation (grant no. 61913, Transforming the field of cultural evolution and its application to global human futures). Edinburgh Zoo’s Living Links Research Facility and Budongo Research Unit is core supported by the Royal Zoological Society of Scotland (Registered charity no. SC004064) through funding generated by its visitors, members and supporters and by the University of St Andrews (Registered charity no. SC013532) who core supports the maintenance and management costs of the research facilityHumans have been suggested to possess uniquely enhanced memory for sequences, based on sequence discrimination learning (SDL) tasks involving arbitrarily ordered sequences with no functional connection to outcomes. Such tasks underestimate animals' SDL as they lack affordances of real-world situations. We tested whether stimuli causally connected to outcomes facilitate SDL. A total of 13 chimpanzees, 24 capuchin monkeys, 23 squirrel monkeys, 77 adult and 239 juvenile humans completed an AB versus BA, BB and AA task. Humans discriminated causal sequences better than arbitrary ones and one chimpanzee succeeded in the causal frame condition after 324 trials, suggesting that performance gaps in previous studies are partly due to the arbitrariness of sequences (monkeys mostly failed the training). Without causal framing, children found the task difficult until 10-11 years of age. The sequence memory hypothesis needs to be evaluated with a broader set of tasks and account for cultural scaffolding of participants' understanding of task requirements.Peer reviewe
A cholinergic spinal pathway for the adaptive control of breathing
Get PDFThe ability to amplify motor neuron (MN) output is essential for generating high intensity motor actions. This is critical for breathing that must be rapidly adjusted to accommodate changing metabolic demands. While brainstem circuits generate the breathing rhythm, the pathways that directly augment respiratory MN output are not well understood. Here, we map first-order inputs to phrenic motor neurons (PMNs), a key respiratory MN population that initiates diaphragm contraction to drive breathing. We identify a predominant spinal input from a distinct subset of genetically-defined V0C cholinergic interneurons. We find that these interneurons receive phasic excitation from brainstem respiratory centers, augment phrenic output through M2 muscarinic receptors, and are highly activated under a hypercapnia challenge. Specifically silencing cholinergic interneuron neurotransmission impairs the breathing response to hypercapnia. Collectively, our findings identify a novel spinal pathway that amplifies breathing, presenting a potential target for promoting recovery of breathing following spinal cord injury.Peer reviewe
Synergistic cross-coupling catalysis : a trialkylphosphine/Pd catalyst tethered to MOF-808(Hf) is very effective for Suzuki-Miyaura coupling of problematic nucleophiles
Get PDFFunding: The authors acknowledge the EPSRC and GSK for an iCase studentship for Soneni Ndlovu (EP/T51746X/1). They also gratefully acknowledge support from the EPSRC through grant numbers EP/L017008/1, EP/R023751/1 and EP/T019298/1.Hafnium and zirconium forms of the benzene-1,3,5-tricarboxylate metal organic framework MOF-808 were prepared from aqueous solution and modified post-synthetically with 3-{(4-methoxy-phenyl)thio}propane-1-sulfonate (MPTPS) and 3-(di-tert-butylphosphino)propane-1-sulfonate (DTBPPS). Their ligands were stoichiometrically loaded with Pd2+. Pd@DTBPPS-MOF-808 is found to be a good catalyst for the Suzuki–Miyaura coupling of functionalised aryl boronic acid derivatives with aryl bromides and unactivated aryl chlorides and the MOF-808(Hf)-based catalysts show significant promise for some highly demanding cross-coupling combinations featuring electron deficient nucleophiles that suffer from poor transmetalation and significant protodeborylation. Remarkably, these led to strongly improved conversions over those based on MOF-808(Zr).Peer reviewe
‘I’m dead!’ : action, homicide and denied catharsis in early modern Spanish drama
Get PDFIn early modern Spanish drama the expression ‘¡Muerto soy!’ (‘I’m dead!’) is commonly used to indicate a literal death or to figuratively express a character’s extreme fear or passion. Recent studies, even one collection published under the title of ¡Muerto soy!, have paid scant attention to the phrase in context, a serious omission when one considers the large proportion of comedia studies dedicated to the combined themes of violence, catharsis and audience reaction. Using a corpus-based analysis of over 300 plays by Lope de Vega as a starting point, this paper will trace the use of ‘muerto soy’ to indicate physical injury and incipient death on the stage and off. These incidents will also be related to dramatic catharsis in early modern Spanish theory and practice. By digging deep into the data and looking carefully at some representative examples, this study will also reveal that moments of seemingly shock-filled catharsis for the audience, when characters declare their own annihilation, are actually relatively perfunctory prompts in a predictably entertaining string of events on stage.Peer reviewe
MRAP2 modifies the signaling and oligomerization state of the melanocortin-4 receptor
Get PDFFunding: This work was supported by the Deutsche Forschungsgemeinschaft (DFG) (German Research Foundation) through SFB1423, Project-ID 421152132, subprojects C03 (to P.A., M.J.L.), B02 (to H.B.), A01/Z03 (to P.S.), A04/B01/Z03 to (A.G. B.-S.). P.A. would like to acknowledge generous funding from the Leverhulme Trust RL-2022-015. Funding was received through Germany’s Excellence Strategy–EXC 2008–390540038–UniSysCat (Research Unit E) (to G.K. and P.S.) and by the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Skłodowska-Curie grant agreement No 956314 [ALLODD] (to P.S.). UKRI funding to P. McC. CIHR funding (PJT-183758) to M.B. FRQS PhD scholarship to S.-A.L.The melanocortin-4 receptor is a G protein-coupled receptor and a key regulator of appetite and metabolism. It can interact with the melanocortin-receptor accessory protein 2, a single transmembrane helix protein known to interact with several different G protein-coupled receptors. However, the consequences of this interaction are not completely understood. Here we report that co-expression of melanocortin-receptor accessory protein 2 has multiple effects on the melanocortin-4 receptor: it enhances G protein-mediated signaling and simultaneously impairs β-arrestin2 recruitment and, consequently, internalization. In addition, co-expression of melanocortin-receptor accessory protein 2 leads to an increased number of monomers of melanocortin-4 receptor by disrupting receptor oligomers. A structural homology model of the active state melanocortin-4 receptor – melanocortin-receptor accessory protein 2 – Gαs complex suggests interaction sites that are relevant for receptor activation. Our data indicate that melanocortin-receptor accessory protein 2 is an accessory protein that interacts with and influences melanocortin-4 receptor structure, biasing its signaling towards G protein-mediated effects.Peer reviewe
The Hippo signaling pathway as a therapeutic target in Alzheimer's disease
Get PDFFunding: This research was funded by Alzheimer’s Research UK, the Alzheimer’s Society, the RS Macdonald Charitable Trust, and the University of St Andrews.The Hippo signaling pathway is well-known for its regulation of organ size, cell proliferation, apoptosis, and cell migration and differentiation. Recent studies have demonstrated that Hippo signaling also plays important roles in the nervous system, being involved in neuroinflammation, neuronal differentiation, and neuronal death and degeneration. As such, dysregulation of Hippo signaling, particularly of its core kinases MST1/2 and LATS1/2, has begun to attract attention in the Alzheimer’s disease (AD) field. Here, we discuss the therapeutic potential of targeting the Hippo pathway in AD by providing an overview of Hippo signaling with regards to its function in the nervous system, evidence for its dysregulation in AD patients and models, and recent studies involving genetic or pharmacological modulation of this pathway in AD.Peer reviewe
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