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Working memory and executive functions: theoretical advances
Get PDFThis editorial presents a special collection on working memory and executive functions. Six articles are presented and their contributions to current theoretical debates are briefly discussed
Understanding and tuning Fe‐doping on Zn–Fe layered double hydroxide particle and photocatalytic properties
Get PDFZn-based layered double hydroxides (LDHs) are promising photocatalytic materials, but their synthesis faces environmental and economic challenges. Oxidative ionothermal synthesis (OIS) offers a green route for zinc oxide synthesis using ionic liquids. To reduce costs, the OIS method uses recovered zinc-containing mixed metal systems, such as electric arc furnace dust, instead of pure metallic Zn. Understanding the interaction of Zn with impure metals during oxidation is essential. This study employs 1-Butyl-3-methylimidazolium chloride ([BMIM]Cl) as the solvent and Fe-doped metallic Zn, the most common waste-stream metal, as the starting material. This study applies quartz crystal microbalance with dissipation to monitor product formation, and X-ray diffraction and scanning electron microscopy to characterize composition and morphology. Results show that FeCl2 doping accelerates the reaction, transforming simonkolleite to Zn–Fe LDH with tunable morphologies. A reaction mechanism for Zn in [BMIM]Cl with FeCl2 is proposed. Photocatalytic hydrogen production tests reveal a favorable hydrogen evolution rate of 20.9 μmol h−1 g−1 with 0.45 M FeCl2 doping, attributed to improved surface structure and crystallinity of the hydrotalcite
Composite variable bias: causal analysis of weight outcomes
Get PDFBackground
Researchers often use composite variables (e.g., BMI and change scores). By combining multiple variables (e.g., height and weight or follow-up weight and baseline weight) into a single variable it becomes challenging to untangle the causal roles of each component variable. Composite variable bias—an issue previously identified for exposure variables that may yield misleading causal inferences—is illustrated as a similar concern for composite outcomes. We explain how this occurs for composite weight outcomes: BMI, ‘weight change’, their combination ‘BMI change’, and variations involving relative change.
Methods
Data from the National Child Development Study (NCDS) cohort surveys (n = 9223) were analysed to estimate the causal effect of ethnicity, sex, economic status, malaise score, and baseline height/weight at age 23 on weight-related outcomes at age 33. The analyses were informed by a directed acyclic graph (DAG) to demonstrate the extent of composite variable bias for various weight outcomes.
Results
Estimated causal effects differed across different weight outcomes. The analyses of follow-up BMI, ‘weight change’, ‘BMI change’, or relative change in body size yielded results that could lead to potentially different inferences for an intervention.
Conclusions
This is the first study to illustrate that causal estimates on composite weight outcomes vary and can lead to potentially misleading inferences. It is recommended that only follow-up weight be analysed while conditioning on baseline weight for meaningful estimates. How conditioning on baseline weight is implemented depends on whether baseline weight precedes or follows the exposure of interest. For the former, conditioning on baseline weight may be achieved by inclusion in the regression model or via a propensity score. For the latter, alternative strategies are necessary to model the joint effects of the exposure and baseline weight—the choice of strategy can be informed by a DAG
Strategy diffusion and conformity in evolutionary dynamics on general networks
Get PDFNetworks of social interactions can drive the dynamics of socio-technical systems. In groups, where strategic decisions are shaped by the tension between cooperation and defection, the replicator equation serves as a valuable tool underpinning the modelling of evolutionary dynamics of strategies. In this work, we integrate the replicator dynamics with an SI (Susceptible-Infected) model for information diffusion in general networks. Considering also conformity, we model the evolution of cooperation in a public good game. The trajectories of the resulting dynamical systems converge to consensus about an internal point solution in the snowdrift setting and boundary solutions of full cooperation or full defection in social dilemmas, asymmetric games and stag hunt settings. Through the application of the Lyapunov stability theorem, we establish the stability of the internal equilibrium point. We then examine the basin of attraction obtaining the conditions leading to full cooperation. This work is relevant for the study of social dynamics in groups where strategic interactions are mediated by conformity
The structural organisation of pentraxin-3 and its interactions with heavy chains of inter-α-inhibitor regulate crosslinking of the hyaluronan matrix
Get PDFPentraxin-3 (PTX3) is an octameric protein, comprised of eight identical protomers, that has diverse functions in reproductive biology, innate immunity and cancer. PTX3 interacts with the large polysaccharide hyaluronan (HA) to which heavy chains (HCs) of the inter-α-inhibitor (IαI) family of proteoglycans are covalently attached, playing a key role in the (non-covalent) crosslinking of HC•HA complexes. These interactions stabilise the cumulus matrix, essential for ovulation and fertilisation in mammals, and are also implicated in the formation of pathogenic matrices in the context of viral lung infections. To better understand the physiological and pathological roles of PTX3 we have analysed how its quaternary structure underpins HA crosslinking via its interactions with HCs. A combination of X-ray crystallography, cryo-electron microscopy (cryo-EM) and AlphaFold predictive modelling revealed that the C-terminal pentraxin domains of the PTX3 octamer are arranged in a central cube, with two long extensions on either side, each formed from four protomers assembled into tetrameric coiled-coil regions, essentially as described by (Noone et al., 2022; doi:10.1073/pnas.2208144119). From crystallography and cryo-EM data, we identified a network of inter-protomer salt bridges that facilitate the assembly of the octamer. Small angle X-ray scattering (SAXS) validated our model for the octameric protein, including the analysis of two PTX3 constructs: a tetrameric 'Half-PTX3' and a construct missing the 24 N-terminal residues (Δ1-24-PTX3). SAXS determined a length of ∼520 Å for PTX3 and, combined with 3D variability analysis of cryo-EM data, defined the flexibility of the N-terminal extensions. Biophysical analyses revealed that the prototypical heavy chain HC1 does not interact with PTX3 at pH 7.4, consistent with our previous studies showing that, at this pH, PTX3 only associates with HC•HA complexes if they are formed in its presence. However, PTX3 binds to HC1 at acidic pH, and can also be incorporated into pre-formed HC•HA complexes under these conditions. This provides a novel mechanism for the regulation of PTX3-mediated HA crosslinking (e.g., during inflammation), likely mediated by a pH-dependent conformational change in HC1. The PTX3 octamer was found to associate simultaneously with up to eight HC1 molecules and, thus, has the potential to form a major crosslinking node within HC•HA matrices, i.e., where the physical and biochemical properties of resulting matrices could be tuned by the HC/PTX3 composition
Symbolic and technical principles of scenography in Europe : 'Light and Darkness: Temporality, atmosphere and audience experience'
No full textRadical (re) readings of Polanyi: splitting hairs and building bridges
Get PDFKarl Polanyi has inspired generations of critical scholars and debates about his work show no sign of abating. This reflects the relevance of his ideas and the multiple ways in which they have been interpreted. In a recent article in this journal, Alcock [(2024). Re-embedding Polanyi’s double movement thesis: The non-ideological and destructive countermovement. Globalizations] contributes to these debates by offering a novel reading of one of Polanyi’s core concepts – the ‘countermovement’. He argues that it is best understood as ‘non-ideological’ and ‘destructive’ and that alternative readings of the concept are ‘disembedded’ from Polanyi’s writing. In response, this article discusses the strengths and weaknesses of Alcock’s formulation and makes the case for multiple ‘embedded’ readings of the concept rather than a single definitive interpretation. It concludes by calling for greater unity and solidarity between critical scholars. This article deepens discussions about Polanyian theory and contributes to debates about the capitalist conjuncture, including the growing threat of fascism
Predictors of response to low-dose amitriptyline for irritable bowel syndrome and efficacy and tolerability according to subtype: post hoc analyses from the ATLANTIS trial.
Get PDFBackground
Low-dose amitriptyline, a tricyclic antidepressant (TCA), was superior to placebo for irritable bowel syndrome (IBS) in the AmitripTyline at Low-dose ANd Titrated for Irritable bowel syndrome as Second-line treatment (ATLANTIS) trial.
Objective
To perform post hoc analyses of ATLANTIS for predictors of response to, and tolerability of, a TCA.
Design
ATLANTIS randomised 463 adults with IBS to amitriptyline (232) or placebo (231). We examined the effect of baseline demographic and disease-related patient characteristics on response to amitriptyline and the effect of amitriptyline on individual symptoms and side effects by subtype.
Results
There was a quantitative difference in amitriptyline effectiveness in those ≥50 years vs <50 on the IBS severity scoring system (IBS-SSS) (interaction p=0.048, mean difference in ≥50 years subgroup −46.5; 95% CI −74.2 to −18.8, p=0.0010), and subjective global assessment of relief (interaction p=0.068, OR in ≥50 years subgroup 2.59; 95% CI 1.47 to 4.55, p=0.0010), and those in the 70% most deprived areas of England compared with the 30% least deprived for a ≥30% improvement in abdominal pain (interaction p=0.021, OR in 70% most deprived subgroup 2.70; 95% CI 1.52 to 4.77, p=0.0007). Stronger treatment effects were seen in men, with higher Patient Health Questionnaire-12 scores, and with IBS with diarrhoea. Mean differences in individual IBS-SSS components favoured amitriptyline, and side effects were similar, across almost all IBS subtypes.
Conclusion
These exploratory analyses demonstrate there are unlikely to be deleterious effects of amitriptyline in any particular IBS subtype and could help identify patients in whom amitriptyline may be more effective
Pedestrian crossing decisions can be explained by bounded optimal decision-making under noisy visual perception
Get PDFThis paper presents a model of pedestrian crossing decisions based on the theory of computational rationality. It is assumed that crossing decisions are boundedly optimal, with bounds on optimality arising from human cognitive constraints. While previous models of pedestrian behaviour have been either ‘black-box’ machine learning models or mechanistic models with explicit assumptions about cognitive factors, we combine both approaches. Specifically, we mechanistically model noisy human visual perception and model reward considering human constraints in crossing, but we use reinforcement learning to learn boundedly optimal behaviour policy. The model reproduces a larger number of known empirical phenomena than previous models, in particular: (1) the effect of the time to arrival of an approaching vehicle on whether the pedestrian accepts the gap, the effect of the vehicle's speed on both (2) gap acceptance and (3) pedestrian timing of crossing in front of yielding vehicles, and (4) the effect on this crossing timing of the stopping distance of the yielding vehicle. Notably, our findings suggest that behaviours previously framed as ’biases’ in decision-making, such as speed-dependent gap acceptance, might instead be a product of rational adaptation to the constraints of visual perception. Our approach also permits fitting the parameters of cognitive constraints and rewards per individual to better account for individual differences, achieving good quantitative alignment with experimental data. To conclude, by leveraging both RL and mechanistic modelling, our model offers novel insights into pedestrian behaviour and may provide a useful foundation for more accurate and scalable pedestrian models
Living with the Dead: Memories, Histories, and the Stories Families Tell in Modern Britain
Get PDFThe dead are everywhere in family life. From a great-grandmother’s recipe made time and again, to a dog-eared black-and-white photo of a family on a beach, and from a carefully curated family bible to a much-told story of a family fleeing their home many decades ago, families are made by their pasts. This book examines the relationship between the living and the dead within family life, charting the way families create afterlives for their ancestors. It asks who and what gets to be remembered, and why. Considering different points of connection with the dead in each chapter—through graves, homes, things, photos, writing, research, and stories—this book shows how death and the dead remain a crucial presence within family life. Through an innovative methodology of collaborative critical family history, Living with the Dead features interviews, personal archives, and the results of a collaboration with fifteen family historians, including the author’s own family. What results is a unique way of getting inside families in the past, of charting not only how families have remembered their dead and passed on their histories over time, but the mechanisms of how histories are constructed and shared. Living with the Dead reveals how crucial the dead and stories of them are within families, and provides new ways for historians to unpick the way history is intimately made
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