Evidence indicates hypervitaminosis A may be attributed to overconsumption of natural preformed vitamin A (VA) and overlapping VA intervention strategies. Hypervitaminosis A can disrupt metabolic processes; however, the extent and mechanisms of these impacts are not well understood. This study aims to assess metabolic differences related to hypervitaminosis A and VA supplementation by performing metabolomics analysis. A subsample of South African preschoolers participating in the country’s VA supplementation programme was selected. Participants were divided into two groups: adequate VA (n 15; 0·59–0·99 µmol/g total liver reserve and high VA (n 15; ≥ 1·0 µmol/g total liver reserve). Serum samples were collected at baseline and 28 d after consuming a 200 000 IU VA supplement. Lipidomics and oxylipins assays were conducted using ultraperformance LC-MS. At baseline, unsaturated lysophosphatidylcholines and unsaturated phosphatidylcholines were significantly lower in the high VA group (P < 0·05). A group-by-time interaction with VA supplementation was observed for polyunsaturated lysophosphatidylcholines and polyunsaturated phosphatidylcholines (P < 0·05). Additionally, a group effect was noted for oxylipins, and a time effect in response to VA supplementation was seen with decreased arachidonic acid and lipoxygenase- and non-enzymatically derived oxylipins (P < 0·05). Hypervitaminosis A is associated with modifications in lipids involved in cell structure and signalling, particularly unsaturated lysophosphatidylcholines and phosphatidylcholines. Further research is needed to identify the mechanisms behind these modifications, their physiological effects and their potential as biomarkers of elevated vitamin A status.

Dietary choline and betaine, suggested as neuroprotective nutrients, have not been sufficiently studied in relation to psychological disorders. This study aimed to investigate the association between dietary choline and betaine and common psychological disorders (depression, anxiety and psychological distress) among Iranian adults. Using a multistage cluster random sampling method, 533 middle-aged adults were included in this cross-sectional study. Dietary intakes were assessed using a validated semi-quantitative 168-item FFQ. Depression, anxiety and psychological distress were evaluated using the Hospital Anxiety and Depression Scale and the General Health Questionnaire, both validated for the Iranian population. Binary logistic regression was applied to explore the associations. Mean age of participants was 42·6 (sd 11·14) years; of whom 18·9, 5·1 and 33·4 % had depression, anxiety and psychological distress, respectively. In the crude model, the highest intake of choline was negatively associated with depression (OR = 0·52; 95 % CI: 0·30, 0·91), anxiety (OR = 0·38; 95 % CI: 0·14, 0·99) and distress (OR = 0·60; 95 % CI: 0·38, 0·94) compared with the lowest intake. After considering all confounders, such associations remained significant in the case of depression (OR = 0·51; 95 % CI: 0·26, 0·98) but not for anxiety and distress. Additionally, there was no significant association between betaine intake and odds of depression, anxiety or distress in both crude and adjusted models. This study suggests a protective association between choline intake and depression, while no significant relation was found in the case of anxiety and distress. Betaine intake was not related to psychological disorders. Further prospective studies are crucial to replicate these findings.

This work reports the X-ray powder diffraction (XRPD) data recorded at room temperature (293 K) of dibromidodioxido-[(4,4′-di-tert-butyl)-2,2′-bipyridine]molybdenum(VI). The analysis of the powder diffraction pattern led to an orthorhombic united cell with parameters a = 17.9205(23) Å, b = 13.4451(16) Å, c = 18.1514(19) Å, V = 4,373.5(11) Å3, and values of Z = 8 and Z’ = 2. The crystal structure of this material corresponds to the structure of entry IFUJEC of the Cambridge Structural Database (CSD), determined at 90 K. The excellent Rietveld refinement, carried out with General Structure and Analysis Software II (GSAS-II), showed the single-phase nature of the material and the good quality of the data. This material was also characterized by elemental analysis, UV–vis, Fourier transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance (1H-NMR) techniques.

Bimetallic Pt nanoparticles play a critical role in various applications, including catalysis, chemical production, fuel cells, and biosensing. In this study, we start with Au@Pt core–shell structure and investigate the evolution of these nanoparticles at elevated temperatures. Our in-situ X-ray diffraction study at elevated temperatures concluded that the onset of Au–Pt alloying occurs between 500 and 600 °C. At higher temperatures, the nanoparticles gradually approached the state of a solid solution, but the composition across the nanoparticles was not uniform even at 1,000 °C. Our results suggest that the alloyed nanoparticles at high temperatures are dominated by one solid solution but contain distinct regions with slightly different compositions.

We study the uniform convergence rates of nonparametric estimators for a probability density function and its derivatives when the density has a known pole. Such situations arise in some structural microeconometric models, for example, in auction, labor, and consumer search, where uniform convergence rates of density functions are important for nonparametric and semiparametric estimation. Existing uniform convergence rates based on Rosenblatt’s kernel estimator are derived under the assumption that the density is bounded. They are not applicable when there is a pole in the density. We treat the pole nonparametrically and show various kernel-based estimators can attain any convergence rate that is slower than the optimal rate when the density is bounded uniformly over an appropriately expanding support under mild conditions.

The article examines the challenges that urban teachers faced in unitary systems, where students of different ages and educational levels shared the same classroom and were taught by a single teacher. It aims to compare these challenges across several cities including Alicante, Badajoz, Cádiz, Canary Islands, Málaga, and Zaragoza to determine common issues within Spain. The study is based on sixteen technical reports from 1916 to 1926 and uses qualitative methods to analyze teachers’ narratives for deeper insights. Additionally, a literature review and quantitative analysis of Spanish statistical sources were conducted. Key findings highlight parental disinterest as a significant cause of school absenteeism. The article concludes by stressing the importance of understanding historical educational contexts in informing current educational policies and practices.

Changes in the characterization of communicative competence, especially in the context of large-scale testing, are typically driven by an evolving understanding of real-world communication and advancements in test construct theories. Recent advances in AI technology have fundamentally altered the way language users communicate and interact, prompting a reassessment of how communicative competence is defined and how language tests are constructed.

In response to these significant changes, an AI-mediated interactionalist approach is proposed to expand communicative competence. This approach advocates for extending the traditional concept of communicative competence to encompass AI digital literacy skills and broadened cognitive and linguistic capabilities. These skills enable effective AI tool usage, as well as the interpretation and application of AI-generated outputs and feedback, to improve communication. Embedding these competencies into language assessments ensures alignment with contemporary communication dynamics, enhancing the relevance of language assessments, and preparing learners for navigating AI-augmented communication environments.

While high-stakes testing faces considerable challenges in adopting this expanded construct, low-stakes formative assessments, where scores do not influence critical decisions about individuals and where opportunities exist to rectify errors in score-based actions, if any, provide a fertile ground for exploring the integration of AI tools into assessments. In these contexts, educators can explore giving learners access to various AI tools, such as editing and generative tools, to enhance assessment practices. These explorations can start to address some of the conceptual challenges involved in applying this expanded construct definition in high-stakes environments and contribute to resolving practical issues.

Radiocarbon dating is a widely used method in archaeology and earth sciences, but the precision of calibrated dates from single radiocarbon measurements can be difficult to understand. This study investigates the precision of calibrated radiocarbon dates depending on the uncertainties of the measurement and the details of the calibration curve. Using data for the Holocene epoch and the IntCal20 calibration curve, over 1,000,000 hypothetical radiocarbon measurements were calibrated and analyzed. The study shows that high-precision measurements can yield calibrated date ranges from less than 50 years to more than 200 years (at the 95.4% probability) depending on the specifics of the calibration curve. This research may serve as a tool for planning future studies and assessing whether high-precision measurements are beneficial for proposed case.

In the classification of complete first-order theories, many dividing lines have been defined in order to understand the complexity and the behavior of some classes of theories. In this paper, using the concept of patterns of consistency and inconsistency, we describe a general framework to study dividing lines and introduce a notion of maximal complexity by requesting the presence of all the exhibitable patterns of definable sets. Weakening this notion, we define new properties (Positive Maximality and the $\mathrm {PM}^{(k)}$ hierarchy) and prove some results about them. In particular, we show that $\mathrm {PM}^{(k+1)}$ theories are not k-dependent. Moreover, we provide an example of a $\mathrm {PM}$ but $\mathrm {NSOP}_4$ theory (showing that $\mathrm {SOP}$ and the $\mathrm {SOP}_n$ hierarchy, for $n \geq 4$, cannot be described by positive patterns) and, for each $1<k<\omega $, an example of a $\mathrm {PM}^{(k)}$ but $\mathrm {NPM}^{(k+1)}$ theory (showing that the newly defined hierarchy does not collapse).

Chronological studies are pivotal for understanding different dimensions of the past. Latin America has embraced various archaeometric dating methods, including radiocarbon (14C) dating. This article reviews the development and challenges of radiocarbon databases and datasets in Latin America, analyzing their integration with global projects and highlighting regional disparities. While global databases like IntChron and CARD often marginalize Latin American data, local projects such as ArqueoData, AndesC14, MesoRAD, SAAID and ExPaND focus on regional needs. The fragmentation of radiocarbon data across publications, technical reports, and limited-access archives hinders accessibility and collaboration. This article underscores the necessity of transitioning from static datasets to dynamic web applications, utilizing APIs to enhance data interoperability, incorporating FAIR principles (findability, accessibility, interoperability, and reusability). This article proposes embedding Latin American initiatives within stable, local institutions to ensure sustainability, establishing classification standards for both radiocarbon dates and associated archaeological contexts. Interdisciplinary collaboration between archaeologists and computer scientists is crucial to developing robust, interoperable databases. By embracing these strategies, Latin America can bridge technological and economic gaps, strengthening its contribution to global archaeological research and fostering new insights into the region’s past.

The Centenary of the First World War saw unprecedent prominence given to the ‘colonial contribution’ in commemorative discourse. While this newfound public recognition sometimes relied on simplistic and sanitised narratives of the war, scholarship produced in the period has greatly enriched understandings of how conflict was experienced by colonised peoples. In this article, I explore the utility of one of the key conceptual innovations of the Centenary, the Greater War, for the analysis of colonial experiences of the conflict. I do this by considering three key questions: Can the Greater War framework facilitate new comparative histories of violence in the war? How do its expanded chronologies account for colonial contexts? Can we adapt its conceptual frameworks to better integrate colonial histories? Exploring the potential answers to these questions will point to new avenues of research that can ensure the colonial is effectively incorporated into our narratives of the global conflict.