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Temperature‐Dependent Lithium Migration and Increased Thermal Stability Within Palladium Nanoparticles
Get PDFThe incorporation of light‐element dopants into monometallic nanoparticle catalysts enables precise modulation of their electronic structures, thereby tailoring catalytic performance. However, despite the widespread use and general understanding of such systems, fundamental aspects of dopant–framework interactions and solid‐solution behavior in light‐element‐doped metal nanoparticles remain incompletely characterized. Here, using a one‐step synthesis of lithiated palladium (Pd) nanoparticles formed by an in situ lithiation process with lithium (Li) acetate, we investigate the temperature‐dependent phase behavior of the Pd–Li solid solution by variable‐temperature synchrotron powder X‐ray diffraction (VT‐SPXRD). In situ thermal Bragg diffraction studies reveal unexpected delithiation dynamics and phase complexity in the metastable PdLi intermetallic compound, including previously unreported temperature‐dependent lithium migration and site‐occupancy redistribution. Remarkably, we demonstrate that interstitial lithium doping enhances thermal stability from 150 °C to over 400 °C, with higher lithium loadings (0.5–1.5 eq) maintaining structural integrity up to 515 °C. This unexpected stabilization, attributed to nanoparticle encapsulation effects, provides fundamental insight into light‐element doping mechanisms in metallic nanoparticles and paves the way for the rational design of electronically tuned nanocatalysts
Differential motor signatures in isolated and narcolepsy-related REM sleep behaviour disorder: a preliminary study
Get PDFBackground: REM sleep behaviour disorder (RBD) is a prodrome of α-synucleinopathy, yet mechanistic pathways are unresolved. Narcolepsy type 1 with RBD (NT1-RBD) provides a human model of orexin deficiency. We tested whether REM motor semiology differs categorically between isolated RBD (iRBD) and NT1-RBD. Methods: We retrospectively analyzed blinded video-polysomnographic scorings from 57 patients (iRBD n = 34; NT1-RBD n = 23). Across 857 REM events (iRBD 717; NT1-RBD 140), we classified topography (head/neck, trunk, upper, lower limbs), complexity (elementary vs. complex), content (scenic, violent, self-referential), vocal/orofacial features, spatial distribution and laterality using a pre-specified codebook. The patient was the primary unit of inference. Binary features used Fisher’s exact tests with Cohen’s h; the per-patient complex-event proportion used Mann–Whitney and Cliff’s δ (bootstrap 95% CI). Robustness checks comprised Beta-Binomial posteriors (Beta [1,1]) and patient-label permutation tests (10,000 permutations). Results: REM motor phenotypes diverged categorically. Lower-limb dominance occurred in 18/23 (78.3%) NT1-RBD vs. 7/34 (20.6%) iRBD (Fisher p < 0.0001; Cohen’s h ≈ +1.23), whereas upper-limb dominance occurred in 24/34 (70.6%) iRBD vs. 2/23 (8.7%) NT1-RBD (p < 0.0001; h ≈ −1.40). Any complex event was present in 27/34 (79.4%) iRBD vs. 3/23 (13.0%) NT1-RBD (p < 0.0001; h ≈ −1.46); violent enactments in 16/34 (47.1%) vs. 0/23 (0%) (p < 0.0001; h ≈ −1.51). The per-patient complex-event proportion was higher in iRBD [median 0.21 (0.05–0.33)] than NT1-RBD [0.00 (0.00–0.00)] (Mann–Whitney p < 0.0001; Cliff’s δ = −0.665; 95% CI −0.853 to −0.441). Event-level summaries were concordant; permutation p-values were 0.0001 for upper-limb involvement and 0.0083 for complex behaviour. Conclusion: iRBD and NT1-RBD exhibit qualitatively distinct REM motor phenotypes: upper-body-dominant, complex/scenic behaviours in iRBD versus elementary, predominantly bilateral lower-limb behaviours with notable trunk recruitment in NT1-RBD, supported by large effect sizes and convergent robustness checks. These findings motivate mechanistic studies of hypothalamic-brainstem-cortical integration in REM and suggest that semiological profiling may aid stratification in prodromal neurodegeneration
Community experiences of surgery in peri-urban Cape Town
Get PDFBackground. Surgical care is critical for addressing universal access to healthcare, but access to safe and timely surgery is limited, especially in poorly resourced settings.
Objective. To determine the surgical experiences of individuals in a peri-urban community in Cape Town, South Africa.
Methods. A cross-sectional household survey of individuals in a peri-urban Cape Town community was conducted with door-to door interviews by trained community assistants, who provided multilingual translation of study materials as needed. The study (i) describes the surgical burden of disease and outcomes; (ii) assesses health-seeking behaviour and barriers to care using the Three Delays framework; and (iii) uses descriptive statistics to characterise respondent demographics and surgical experiences and χ2 tests to compare awareness, attitudes and acceptability across genders and locations.
Results. Data from 432 valid responses of 450 surveys conducted showed that chronic diseases were common, affecting 240/431 (56%), with a higher prevalence in females than in males (171/285 (60%) v. 63/133 (47%), p<0.05). Most participants (208/432, 44%) lived within 10 km of their nearest healthcare facility, predominantly public facilities (417/432, 97%). The Three Delays framework showed that 87/432 (20%) delayed seeking surgical care, 114/432 (26%) experienced delays reaching facilities and 95/432 (32%) faced delays in receiving appropriate care, while 95/432 (22%) reported no delays. The surgical burden was substantial, with 260/428 (60%) having undergone surgery in their lifetime and 195 surgical procedures performed in the last 5 years. Postoperative disability affected 43/432 (10%) of participants, primarily manifesting as body function impairments (22/43, 51.2%) and activity limitations (7/43, 16.3%). Only 67% understood post-surgical treatment protocols.
Conclusion. This study reveals significant challenges in surgical care delivery in this peri-urban community. Key findings include a high chronic disease burden, substantial delays in accessing surgical care and significant postoperative disability rates. These results provide the first comprehensive assessment of surgical experiences in peri-urban Cape Town, highlighting the need for comprehensive interventions targeting chronic disease and surgical care, even in peri-urban areas close to public health facilities
The performance of REBCO coated conductor during in situ cryogenic irradiation with fusion-spectrum neutrons
Get PDFUnderstanding the tolerance of REBa2Cu3O 7−x (REBCO) high-temperature superconductors to neutron damage is essential for compact fusion reactor design. Here we report the first in situ measurements of the superconducting performance of REBCO coated conductor (CC) during neutron irradiation. The CC was exposed to 14 MeV neutrons at fluxes up to 7.3 × 107 n cm−2 s−1 while carrying current at 40 K. In situ voltage measurements revealed no instantaneous disruption of superconductivity, but the critical current ( Ic) decreased linearly with fluence at 0.03 A per 1012 n cm−2. Careful analysis excluded thermal effects as the origin of this degradation. Consistent with a point-defect damage mechanism, superconducting performance was recovered fully following room temperature annealing. This observed onset of Ic reduction occurred several orders of magnitude below the critical neutron fluences anticipated by previous ex situ studies, indicating that service lifetimes of REBCO-based magnets may be substantially shorter than current projections
Fertility Norms as Unifying Framework: Coordinating Migration and Fertility Decisions in China′s Internal Migration
Get PDFResearch on the migration‐fertility nexus has generated five theoretical mechanisms – socialisation, assimilation, selection, disruption, and adaptation – that are typically examined in isolation from one another. Drawing on 66 life‐story interviews with internal migrants in Shenzhen, China, this article argues that these mechanisms share a common foundation in fertility norms, understood as socially embedded expectations about reproduction. While socialisation and assimilation have always centred on normative processes, the empirical analysis demonstrates that selection, disruption, and adaptation are likewise mediated by fertility norms – shaping how migrants assess destinations (selection), experience changes in normative constraint (disruption), and reinterpret reproductive expectations across contexts (adaptation). By establishing fertility norms as a unifying analytical lens, the article shows that migration and fertility operate as coordinated life domains. The analysis reveals that prior to migration, individuals evaluate destinations in light of anticipated fertility norms (selection). During migration and settlement, geographic separation from origin communities weakens normative monitoring and sanctioning, creating space for revising reproductive plans (disruption). Over time, sustained exposure to destination contexts reshapes fertility orientations and practices (adaptation), all unfolding against the longer‐term influence of childhood socialisation and intergenerational assimilation. This coordination reveals individuals as strategic navigators who integrate spatial mobility and reproductive decisions together, rather than experiencing them as separate, sequential events
Labour law in Strasbourg
No full textFrom its inception, the European Convention on Human Rights (‘ECHR’) has given the Strasbourg control mechanism – now: the European Court of Human Rights (‘the Court’) and the Committee of Ministers (‘the Committee’) – a labour law mandate. Yet, the Strasbourg control mechanism has met with wide-ranging scepticism from labour lawyers. Two prominent categories of critiques have arisen, arguing that Strasbourg’s recent engagement with labour law is characterised by undue self-restraint (1) in response to political pressure; and/or (2) in respect of collective labour rights in particular. A premise underlying both categories is that Strasbourg’s labour rights output is inconsistent.The comprehensive and serious nature of these concerns demands comprehensive and serious investigation. This thesis responds to that challenge through a systematic and doctrinal review of the output of the modern Strasbourg control mechanism as regards labour rights applications invoking Articles 4 and 11, ECHR, spanning from their receipt by the Registry to supervision of execution by the Committee.This comprehensive review looks afresh at matters previously overlooked or overprioritised in labour lawyers’ engagement with Strasbourg. Crucially, assessment of this broader dataset reveals far greater consistency in the Strasbourg control mechanism’s output than the critiques from labour lawyers suggest. There is an identifiable difference between the Strasbourg control mechanism’s approach to cases involving the State ‘as employer’ and those in which it acts ‘as regulator’. This trend tracks across applications invoking Articles 4 and 11. While the ‘employer’/‘regulator’ distinction is most salient for merits determinations, its effect permeates other determinations.This thesis thus casts new light on the Strasbourg control mechanism’s labour rights output. In doing so, it challenges a key premise underlying labour lawyers’ engagement with Strasbourg to date. Labour lawyers’ response to its findings will therefore shape and direct the vital conversation about Strasbourg’s role in labour law
In the wake of USAID cuts, we can build a Demographic and Health Survey Program founded on more equitable data infrastructure and stronger research integrity
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Calibrating Mid-infrared Emission Features as Diagnostics of Star Formation in Infrared-luminous Galaxies via Radiative Transfer Modeling
Get PDFLuminous infrared (IR) galaxies are key sites of obscured stellar mass assembly at z > 0.5. Their star formation rates (SFRs) are often estimated using the luminosities of the 6.2 and 11.2 μm polycyclic aromatic hydrocarbon (PAH) features or those of the [Ne ii] and [Ne iii] fine-structure lines, as they are minimally affected by obscuration. It is uncertain whether the calibration of these features as SFR tracers depends on the starburst bolometric luminosity or the level of active galactic nucleus (AGN) activity. We here investigate the relationship between the luminosities of PAH and neon lines with SFR for highly luminous objects using radiative transfer modeling and archival observations of 42 local ultraluminous (≥1012L⊙) IR galaxies (ULIRGs). We find that PAH and [Ne ii] features arise mainly in star-forming regions, with small contributions from the AGN or host, but that the [Ne iii] line has a mixed contribution from both star formation and AGN activity. We present relations between LPAH and L[Ne II], and both starburst luminosity and SFR. We find relations for lower-luminosity (LIR ≃ 1010–1012L⊙) systems underestimate the SFRs in local ULIRGs by up to ∼1 dex. The 6.2 and 11.2 μm PAH features, and the [Ne ii] line, are thus good tracers of SFR in ULIRGs. We do not find that a more luminous AGN affects the relationship between SFR and PAH or neon luminosity but that it can make PAH emission harder to discern. Our results and derived relations are relevant to studies of star-forming and composite galaxies at z < 3 with the James Webb Space Telescope
Prediction of COVID-19 hospitalisation, ICU admission or death following ChAdOx1 vaccination using artificial intelligence: A clinical predictive model from the English RAVEN study
Get PDFObjectives: This study identifies predictors of severe COVID-19 following completion of two-dose primary series of the AZD1222 COVID-19 vaccine, employing eXtreme Gradient Boosting (XGBoost) and Shapely additive explanations (SHAP), as an explainable artificial intelligence (AI) approach. Method: A retrospective cohort study using linked primary care data from the Oxford-Royal College of General Practitioners Clinical Informatics Digital Hub (ORCHID), including computerised medical records of over 19 million people in England, for the period from 8th December 2020–31st December 2021, as part of the Real-world effectiveness of the AZD1222 COVID-19 vaccine in England (RAVEN) study. We evaluated a two-dose primary series of the AZD1222 vaccine on COVID-19 related hospitalisation, ICU admission or death. Results: A total of 4,515,280 individuals with a two-dose primary series of AZD1222 vaccine were analysed, where 7,171 individuals had a record of severe COVID-19. Variables with the greatest predictive weight for COVID-19 mortality in vaccinated individuals were age ≥ 85 years, high Cambridge Multi-Morbidity Score, and chronic heart, respiratory and kidney diseases; variables predicting COVID-19 hospitalisation following completed primary series included high CMMS, obesity, and being offered early COVID-19 vaccination in the national vaccine campaign (e.g., vaccinated during the first quarter of 2021); predictors of COVID-19 ICU admission included obesity, female sex, being offered early COVID-19 vaccination in the national vaccine campaign, chronic kidney disease and diabetes. Across models, age ≥ 85 years was highly predictive of mortality and moderately predictive of hospitalisation. However, for ICU admission it was reported as not predictive. Conclusion: Obesity, chronic heart, respiratory and kidney diseases were the main predictors across models, which is comparable to the scientific literature, validating the explainable AI approach. XGBoost can accurately predict severe outcomes in fully vaccinated individuals. Predictive models built on real-world primary care data can help to timely identify individuals to be prioritised for vaccination booster