This article studies bivariate multiple orthogonal polynomials of mixed type on the step-line. The analysis is based on an LU factorization of the moment matrix adapted to this setting. The orthogonality and biorthogonality relations satisfied by these polynomials are identified, and their exact multidegrees are determined. The corresponding recurrence relations and the growing banded matrices that represent them are also derived. Christoffel-Darboux kernels and the associated Christoffel-Darboux-type formulas are obtained. Finally, an ABC-type theorem relating the inverse of the truncated moment matrix to these kernels is established.
Oral lichen planus (OLP) is a common chronic inflammatory disease of the oral mucosa that causes recurrent pain and discomfort, affecting patients' quality of life. Accurate diagnosis is essential, given its potential progression to oral cancer. Segmentation masks allow the extraction of regions of interest for oral lesion diagnosis and often outperform full-image AI analysis, while precise lesion delineation remains crucial for assessing lesion extent, long-term monitoring, and clinical decision-making. However, OLP lesion segmentation remains challenging because of diffuse lesion boundaries and the low contrast between affected areas and surrounding healthy mucosa. In this study, we investigate the parameter-efficient adaptation of a foundation vision transformer, DINOv2, for medical image segmentation by combining low-rank adaptation (LoRA) with a DeepLabV3 decoder. A boundary-aware optimization integrating Dice, Cross-Entropy and differentiable Hausdorff losses is used to improve contour precision. The study was conducted on 668 OLP photographs, pixel-level annotated by a single oral medicine specialist. Evaluation included pixel-wise (Dice, IoU), boundary (HD95) and object-level metrics (TP/FP/FN, precision, recall, F1). Results were compared with established baselines. The proposed model achieved a Dice score of 0.8401, an IoU of 0.7734, and an HD95 of 62.68 px, outperforming all supervised CNN and Transformer baselines; for example, it improved over SegFormer MiT-B2 by +0.0283 Dice, +0.0305 IoU, and-8.12 px HD95. To assess robustness in low-data settings, we trained the model on subsets of different sizes and found that it consistently maintained its advantage. These results highlight the importance of calibrating boundary-sensitive loss components and object-level thresholds according to clinical priorities.
Traditionally, the lack of association between the form of a word and its meaning (i.e. arbitrariness) has been considered a fundamental aspect of language. However, this idea has recently been challenged by growing evidence of form-meaning relationships in words from different conceptual domains, such as size, shape, motion, and colour. More recently, several studies have provided evidence of non-arbitrary associations between the acoustic or phonological forms of words and their meanings when conveying emotional concepts. This phenomenon is referred to as affective iconicity. These effects are evident within and across languages through the over-representation of certain phonemes in words denoting positive or negative emotions (e.g., the phoneme/i/tends to occur in positive words in several different languages) or through statistical regularities in the phonetic features of emotional words (e.g., in English, German and Spanish, sibilant sounds tend to be associated with a high degree of emotional activation of a word’s referent). In this article, we review the literature on affective iconicity. Overall, the current findings suggest that non-arbitrary relationships between word forms and affective meanings may have evolved from the capacity to integrate multimodal inputs with affective experiences. This ability could have been advantageous for communicating information relevant to an individual's survival through language. We argue that affective iconicity effects arise from a link between phonetic and phonological forms and schematic representations of affective experiences and states during the lexicalisation of emotional concepts.
Beyond conventional 3D-perovskite oxides, layered n = 2 Ruddlesden–Popper (RP) phases are attracting increasing interest as catalysts for the oxygen evolution reaction (OER). Here, Sr3Fe1.75M0.25O7-δ (M = Fe, Nb, Ta, and Ru) were synthesized by conventional solid-state reaction and evaluated for catalyzing the OER in alkaline media. All samples exhibited oxygen non-stoichiometry (δ ≈ 0.5) and moderate specific surface areas (≈1.3 m2 g−1), yielding modest OER activity. Among the investigated compositions, M = Fe and Ru exhibited the highest electrocatalytic activity (η ≈ 0.5 V at 2.5 mA cm−2, Tafel slope ≈140 mV·dec−1) whereas d0-cation substitution (M = Nb, Ta) further decreased activity. XRD, SEM-EDS, TEM-EDS and ICP-OES analyses revealed that these n = 2 RP ferrates suffer extensive cation leaching, surface carbonation (SrCO3) and structural degradation in alkaline media, occurring both under active OER operation and by chemical aging in the absence of an applied potential. The specific degradation mechanisms depend on the nature of M. While M = Fe, Ru phases undergo severe structural hydration and form Sr3Fe2(OH)12, substitution with high-valence d0 cations (Nb5+, Ta5+) suppresses the hydration pathway. These results contribute to a broader understanding of the factors that govern the performance and durability of layered Fe-based oxides as OER catalysts.
Objectives Post-pandemic telemedicine in Spain shows a divergence: use has fallen while patient satisfaction has risen. We examine this paradox and its implications for digital health policy. Methods Sequential mixed-methods design. Phase 1 analysed individual-level microdata from four waves (2022–2025) of the nationally representative Spanish Health Barometer using Cochran-Armitage tests and survey-weighted logistic regression, including covariate-adjusted models. Phase 2 comprised semi-structured interviews with ten purposively sampled physicians (eight hospital specialists, one primary care paediatrician and one out-of-hospital emergency physician), interviewed as key informants, analysed with constructivist grounded theory coding procedures in ATLAS.ti 23. Results Remote care use fell from 32.2% to 19.2%, while satisfaction among telephone users rose from 42.3% to 67.1%; both trends were virtually unchanged after adjustment for age, sex, chronic illness and education. Video consultation never exceeded 0.2% of most recent primary care consultations. Physicians described telemedicine as most valuable for monitoring stable, known patients, structurally limited by the absence of physical examination, and constrained by missing video infrastructure, shared records and legal rules. Conclusions The findings are consistent both with a shift from emergency-era mass use toward more clinically targeted use and with better-organised telephone consultations, which the data cannot distinguish. The interviewed physicians defined the clinical scope of remote care. Remote care in Spanish public primary care remains almost entirely telephone-based. The interviewed physicians identified video infrastructure, shared patient records, clear legal frameworks and digital health literacy as conditions for wider remote care, which warrant evaluation as policy priorities.
