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Subtle Cognitive Variability in Foetal Alcohol Syndrome Spectrum: Intelligence Profiles and Verbal Fluency Performance Across Diagnostic Categories in Polish Population
Get PDFBackground/Objectives: The foetal alcohol syndrome spectrum is linked with neurodevelopmental delay and cognitive and educational problems. Direct consequences of prenatal alcohol exposure include impaired processes of neural migration and brain development. Among the important features present in affected children are impaired communicational skills and intelligence. Methods: Here we presented the case-control comparison of 124 children with foetal alcohol syndrome spectrum disorder (FAS: 62 (50%), pFAS: 34 (27.42%) and ARND: 28 (22.58%)) and 53 healthy controls regarding intelligence quotient and a verbal fluency task. The verbal and non-verbal intelligence was measured using the WISC-R scale, and the verbal fluency task encompassed phonemic, semantic and categorial assessment in 15 and 60 s; we used the authors' parental/caregiver survey to determine risk factors. In statistical analysis both methods of classical parametric/non-parametric tests and machine learning algorithms were used. Results: Foetal alcohol syndrome spectrum patients were clearly distinguished from healthy controls regarding total verbal and non-verbal intelligence, as well as all three categories of verbal fluency (p < 0.01). ML methods distinguished an FAS group with 0.49 precision and 80% recall and for pFAS and ARND diagnoses we obtained: 0.50/0.33 precision and 3%/7% recall. None of the parameters analysed in our study differentiated foetal alcohol syndrome, partial foetal alcohol syndrome and alcohol-related neurodevelopmental disorders. Conclusions: Children with foetal alcohol syndrome spectrum disorder markedly differ from healthy control subjects in intelligence and verbal fluency. The diagnostic sub-types of foetal alcohol spectrum are not clearly defined in obtained neuropsychological and clinical data
Stratified manifolds with corners
Get PDFWe define categories of stratified manifolds (s-manifolds) and stratified manifolds with corners (s-manifolds with corners). An s-manifold X of dimension n is a Hausdorff, locally compact topological space X with a stratification X = ∐i∈I Xi into locally closed subsets Xi which are smooth manifolds of dimension ⩽ n, satisfying some conditions.S-manifolds can be very singular, but still share many good properties with ordinary manifolds, e.g. an oriented s-manifold X has a fundamental class [X]fund in Steenrod homology HStn(X, ℤ), and transverse fibre products exist in the category of s-manifolds.S-manifolds are designed for applications in Symplectic Geometry. In future work we hope to show that after suitable perturbations, the moduli spaces M of J-holomorphic curves used to define Gromov–Witten invariants, Lagrangian Floer cohomology, Fukaya categories, and so on, can be made into s-manifolds or s-manifolds with corners, and their fundamental classes used to define Gromov–Witten invariants, Lagrangian Floer cohomology, . . .
Counting answers to unions of conjunctive queries: natural tractability criteria and meta-complexity
Get PDFWe study the problem of counting answers to unions of conjunctive queries (UCQs) under structural restrictions on the input query. Concretely, given a class C of UCQs, the problem #UCQ(C) provides as input a UCQ Ψ ∈ C and a database D and the problem is to compute the number of answers of Ψ in D. Chen and Mengel [PODS’16] have shown that for any recursively enumerable class C, the problem #UCQ(C) is either fixed-parameter tractable or hard for one of the parameterised complexity classes W[1] or #W[1]. However, their tractability criterion is unwieldy in the sense that, given any concrete class C of UCQs, it is not easy to determine how hard it is to count answers to queries in C. Moreover, given a single specific UCQ Ψ, it is not easy to determine how hard it is to count answers to Ψ. In this work, we address the question of finding a natural tractability criterion: The combined conjunctive query of a UCQ Ψ = φ1 ∨ · · · ∨φℓ is the conjunctive query ∧ (Ψ) = φ1∧· · ·∧φℓ. We show that under natural closure properties of C, the problem #UCQ(C) is fixed-parameter tractable if and only if the combined conjunctive queries of UCQs in C, and their contracts, have bounded treewidth. A contract of a conjunctive query is an augmented structure, taking into account how the quantified variables are connected to the free variables — if all variables are free, then a conjunctive query is equal to its contract; in this special case the criterion for fixed-parameter tractability of #UCQ(C) thus simplifies to the combined queries having bounded treewidth. Finally, we give evidence that a closure property on C is necessary for obtaining a natural tractability criterion: We show that even for a single UCQ Ψ, the meta problem of deciding whether #UCQ({Ψ}) can be solved in time O(|D|d ) is NP-hard for any fixed d ≥ 1. Moreover, we prove that a known exponential-time algorithm for solving the meta problem is optimal under assumptions from fine-grained complexity theory. As a corollary of our reduction, we also establish that approximating the Weisfeiler-Leman-Dimension of a UCQ is NP-hard
Ethical considerations for semaglutide use in children
No full textSemaglutide, marketed as Ozempic, Wegovy, and Rybelsus, has rapidly become one of the most prominent medications of recent years. Initially approved in 2021 for type 2 diabetes in adults, semaglutide is now authorized for obesity management in adults and children in several countries, including Germany, the United Kingdom, Denmark, and the United Arab Emirates. Despite this broad regulatory approval, its pediatric use remains a subject of debate. Advocates highlight its potential to reduce cardiovascular risk and prevent obesityrelated illness, while critics emphasize uncertainties about long-term safety, efficacy, and impacts on child development. This paper examines the ethical challenges raised by prescribing semaglutide to children, focusing on access barriers, stigma, and the neglect of structural determinants of obesity, and provides ethical recommendations for clinicians aimed at mitigating harm, supporting autonomy, and promoting children’s health
Lexical inference training for homonyms: two randomized controlled trials for children with English as a first and an additional language
No full textBackground: Many words have multiple meanings which present challenges to learning yet research has yet to identify effective interventions for homonyms. Lexical inference may be a promising strategy.
Aim: To evaluate a brief, novel lexical inference intervention for homonyms.
Samples: Children aged 7–8 years (Study 1: N = 180, Study 2: N = 76). Study 2 included children with English as an Additional Language (EAL, n = 37).
Methods: In two randomised controlled trials, participants were assigned to either inference training or control (Study 1: spatial training; Study 2: implicit exposure through reading). Their receptive knowledge of taught and untaught homonyms was measured before and after the intervention, and in Study 2, metacognitive and inference skills too.
Results: Those in the inference interventions showed greater gains in receptive knowledge than control groups. In study 2, children also showed improvement in the inference test with homonyms, and while children with EAL had a specific challenge with receptive knowledge of homonyms compared to their EL1 peers, the intervention was equally effective for both groups. Receptive knowledge and inference with homonyms predicted unique variance in reading comprehension. The intervention showed limited transfer to untaught words, although patterns of errors provided some indication of improved understanding.
Conclusions: A brief inference training is effective for gaining knowledge of homonyms, with limited transfer to untaught words, and the intervention is equally effective for children with EAL and EL1. The findings also showed the importance of homonym understanding and inference for children’s reading comprehension
'How many interviews do I need?' An examination of interview numbers and sampling moves in qualitative research
Get PDFQualitative researchers face an enduring question: how many interviews do I need? While a variety of guidelines exist, there is limited consensus over which specific factors should determine the number of interviews required. We examined the determination of interview sample sizes in 562 qualitative studies across six high-impact management and organizational journals over a decade. Our findings reveal considerable variance in interview numbers, yet often, limited information is provided on the criteria used to determine them. To promote clearer alignment between sample sizes and methodology, we examined studies with detailed descriptions of their interview sampling. We identified specific ‘sampling moves’ used to determine the number of interviews, categorized into three types—opening, focusing, and closing sampling moves—that researchers use to establish confidence in the sample and support theoretical insights. By implication, our study refutes the notion of a “magic” interview number. Instead, sampling moves are heuristic tools that qualitative researchers can thoughtfully adapt to their analytical aims when determining appropriate sample sizes
On evaluating dimensionality reduction techniques in capturing in-cylinder flow field variations
Get PDFInterpreting complex flows, which may include transient features, non-linearity, and high dimensionality, is challenging because averages may not represent any individual flow field. This work evaluates the variability of dimensionallyreduced flow field data measured using Particle Image Velocimetry (PIV) compared to an ensemble mean, using several novel vector comparison metrics, namely; Weighted Relevance Index (WRI), Weighted Magnitude Index (WMI), and a modified Combined Magnitude and Relevance Index (modified-CMRI). Three dimensionality-reduction techniques were assessed, Proper Orthogonal Decomposition (POD), Dynamic Mode Decomposition (DMD) and Sparsity-Promoting DMD (SPDMD) using the proposed metrics. The PIV data were collected using an optically accessible single-cylinder engine under motored conditions at two crank-angle degrees (CAD), 460 CAD (maximum inlet valve lift) and 700 CAD (a typical spark-timing angle). The results show that the 0 Hz SPDMD mode preserves the vector magnitude and alignment and thereby better captures intake jet dynamics, aligning more closely with individual snapshots than ensemble averaging. Furthermore, the metrics consistently identify discrepant snapshots in both datasets when compared to the 0 Hz SPDMD mode, outperforming the traditional ensemble mean approach. These findings underscore the utility of the proposed vector comparison metrics in evaluating dimensionality reduction techniques and their potential to enhance the analysis of complex flow fields, ultimately aiding in the identification of cycle-to-cycle variations (CCVs) in large incylinder flow datasets. Taken together, the use of SPDMD to extract a physically representative reference flow field and the modified-CMRI to quantify deviations from individual cycles, provides a unified framework for analyzing in-cylinder highly variable flows
Characterization of γ′ Precipitation Kinetics in Additively Manufactured Ni-Based Superalloy ABD®-900AM
Get PDFThe γ′ precipitation behavior in additively manufactured ABD®-900AM is quantified in the temperature range of 700 K to 1200 K (427 °C to 927 °C). Data for γ′ precipitate size distributions and median radii are reported as a function of annealing time and temperature. An empirical model predicting the median γ′ precipitate size during post-build heat treatment is established, and effective diffusion coefficients are determined at the three studied temperatures. A strong correlation between median γ′ precipitate size and bulk hardness is identified, revealing an optimum precipitate size of 10 to 20 nm for maximum hardness and enabling classification of the precipitation process into two stages: γ → γ + γ′ transformation and subsequent coarsening. A time–temperature–transformation (TTT) diagram is constructed and further rationalized using CALPHAD and TC-PRISMA modeling. Notably, interconnected γ′ morphologies are observed at early reaction times (r < 6 nm), indicating the possible involvement of spinodal decomposition in the precipitation mechanism. The work provides comprehensive datasets for thermal stability, mechanical response, and phase evolution in ABD®-900AM and offers insights for post-processing strategies and predictive modeling in AM Ni-based superalloys
Strain Rate-Dependent Deformation Mechanisms in CMSX-4 at 800 °C: Insights from Full-Field Optical Extensometry
Get PDFThe deformation behaviour of a Ni-base single crystal superalloy is studied using a multiscale approach incorporating a recently developed videography arrangement, allowing for full-field digital image correlation. Single crystal CMSX-4 in the 001 orientation was used to obtain a significant tensile dataset spanning temperatures from ambient to 900 °C and strain rates from 10−1 to 10−5 s−1. A multiscale approach was applied particularly to three strain rates at 800 °C, to determine transitions in the deformation mechanisms. It is demonstrated that the macroscopic deformation patterns correlate well with microscopic observations; moreover, the full-field strain mapping offers useful insights into the underlying shear and slip events. The strain rate sensitivity was particularly pronounced in the regime emphasised and evidence is presented for transitions in deformation mechanism within a single test as deformation proceeds