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Factors influencing herders’ willingness to engage in grassland ecological restoration in Ruoergai County

Predictive divergence in machine learning models for clinical mortality risk: A multicohort study of covid-19 patients

Background Machine learning (ML) algorithms are increasingly used in healthcare to support clinical decision-making. While models with similar overall performance are often considered interchangeable for deployment, they may produce divergent predictions, a phenomenon known as algorithmic multiplicity. In such cases, the choice of algorithm may introduce bias. This study investigates the impacts of algorithmic multiplicity in mortality prediction and assesses the influence of patient characteristics on model decisions. Methods A cohort of 4,337 adult patients (≥18 years) with RT-PCR–confirmed covid-19 from five tertiary care hospitals in Brazil was followed from March to August 2020. Five popular ML models for structured data were trained on demographic and laboratory data collected at early hospital admission to predict in-hospital mortality. Model performance, feature importance, and algorithmic prediction similarity were evaluated. Feature distributions were compared between patients correctly or incorrectly classified by all models using paired t-tests or Mann–Whitney U tests, as applicable, at the 5% significance level. Subgroup performance differences were assessed using 10-fold cross-validation applied to five k-means–delineated clusters, compared by one-way ANOVA. Within-cluster predictive divergence was assessed within a 95% confidence interval. Results All models achieved high overall predictive performance (µ = 0.855, σ² = 0.0072). However, the comparison of individual-level predictions revealed substantial heterogeneity, with pairwise prediction correlations ranging from R² = 0.56 to 0.80. Unsupervised k-means clustering identified five clinically distinct patient subgroups with mortality rates ranging from 22% to 80%, within which model performance varied significantly (F = 73.18, p < 0.001). Notably, TabPFN and LightGBM showed superior performance in the “Anemia” cluster, whereas TabPFN underperformed in the “Immunodeficient” cluster (95% CI). Conclusions This study demonstrates that ML models with similar overall performance can yield substantially divergent predictions at both the individual and subgroup levels, and that no single algorithm consistently outperforms others across all patient subgroups. These findings highlight the limitations of relying solely on global performance metrics and underscore the need for context-aware evaluation of ML models in heterogeneous clinical populations.

Joint trajectories of burden and benefits of caregiving among informal caregivers of older adults with functional limitations: a longitudinal study

Correction: Laminin N-terminus α31 regulates corneal epithelial cell adhesion and migration through modifying the organization and proteolytic processing of laminin 332

In-hospital outcomes and temporal analysis of paralyzed patients with acute myocardial infarction undergoing percutaneous coronary intervention

Assessing lactate stability at the minimum lactate steady state velocity in male trained middle-distance runners

Objectives This study investigated the physiological behavior of the running velocity associated with the Minimum Lactate Steady State (vMLaSS), derived from a 6 × 800-m interval protocol, and examined whether this intensity produced stable metabolic and lactate responses during a 30-minute constant-load validation run in trained endurance runners. Methods Fifteen trained male middle- and long-distance runners completed a graded treadmill test to determine maximal oxygen uptake. Following a supramaximal sprint to induce hyperlactatemia, each athlete performed a 30-minute constant-load run at a velocity derived from the lactate-minimum approach. Following a supramaximal sprint to induce hyperlactatemia, each athlete performed a 30-minute constant-speed run at their individually determined MLaSS velocity. Blood lactate samples were collected at 10-minute intervals, and breath-by-breath cardiopulmonary variables were continuously recorded. Lactate kinetics were analyzed using a Friedman test with Wilcoxon signed-rank post-hoc comparisons ( p  < 0.05). Results Blood lactate exhibited significant time-dependent fluctuations during the 30-minute trial (Friedman χ² (3) = 28.72, p  < 0.001). Lactate increased sharply by minute 10, declined at minute 20, and rose again at minute 30, exceeding the classical MLSS criterion of ≤1 mmol·L ⁻ ¹ change during the final 20 minutes. In contrast, cardiopulmonary variables remained stable throughout V̇O₂ (3.43 ± 0.11 L·min ⁻ ¹; p  = 0.86) and V̇CO₂ (3.21 ± 0.14 L·min ⁻ ¹; p  = 0.91). Carbohydrate oxidation predominated (214.5 ± 19.3 g·h ⁻ ¹), whereas fat oxidation remained minimal (–0.9 ± 2.7 g·h ⁻ ¹). Conclusion Despite stable cardiorespiratory and substrate-utilization profiles, the significant variability in blood lactate concentration during the 30-minute constant-load run indicates that the running velocity derived from the lactate-minimum approach did not elicit a lactate steady state in this trained cohort. These findings suggest that physiological responses at the MLaSS-derived intensity may differ from classical steady-state expectations in highly trained endurance runners and highlight the need for direct MLSS verification in future studies.

Correlation between carbon percentage and nanocomposite performance in commodity and engineering thermoplastics (ABS, HIPS, PP, and PC)

Abstract In this study, the effect of graphene nanoplates (GNP) on the mechanical behavior of four engineering thermoplastics Acrylonitrile Butadiene Styrene (ABS), High-Impact Polystyrene (HIPS), Polycarbonate (PC), and Polypropylene (PP) was systematically investigated. Although graphene nanoplates (GNP) have been extensively studied as reinforcing fillers for thermoplastic polymers, the performance of these materials varies greatly depending on the polymer matrix. Uncertainty about how the fundamental chemical composition, especially carbon percentage (C%), affects GNP dispersion and the ensuing mechanical performance is a major unsolved issue. By methodically linking the mechanical response of GNP-reinforced thermoplastics with the polymer carbon content, this study seeks to close this gap. A wide variety of carbon percentages and molecular structures were represented by the selection of four economically significant polymers: ABS, HIPS, PC, and PP. Melt compounding and injection molding were used to create composites with 0.7 weight% GNP. To assess the combined impacts of C% and GNP addition, the suggested approach combines elemental analysis, scanning electron microscopy, X-ray diffraction, and mechanical testing (hardness and impact strength), all of which are backed by a 2 × 4 factorial experimental design. The findings demonstrate that whereas HIPS experiences agglomeration and performance degradation, polymers with more advantageous chemical interactions, such ABS and PP, have better GNP dispersion and improved mechanical characteristics. The derived models’ capacity to reliably relate mechanical behavior, GNP incorporation, and carbon percentage were validated by statistical analysis. These results offer a useful foundation for choosing thermoplastics for nanocomposites based on graphene.

Retraction: Effectiveness of psychosocial interventions for infertile women: A systematic review and meta-analysis with a focus on a method-critical evaluation

Polarimetric imaging of collagen in histopathology specimens: an investigation of congo red and picrosirius red-stained placenta and skin

Abstract Polarisation microscopy is a label-free technique whose tissue architecture profiling through anisotropy remains underinvestigated. In histology, bright-field microscopy and special stains remain the standard for investigating extracellular matrix (ECM) proteins. However, these approaches are qualitative and observer-dependent. By measuring birefringence parameters, quantitative polarisation microscopy (QPM) could offer a more objective alternative. Using dual photoelastic modulators and full Stokes parameter acquisition, QPM was applied to Congo red and picrosirius red-stained sections of human placenta, normal skin, and keloid scars. From the Stokes vectors ( I , Q , U , V ), polarisation azimuth, ellipticity, phase retardation, and depolarisation maps were derived, enabling quantitative characterisation of collagen organisation. QPM revealed distinct anisotropic signatures corresponding to ECM microarchitecture. Picrosirius red-stained sections demonstrated a three/four-fold in phase retardation increase compared to Congo red, confirming its collagen-specific birefringent enhancement. In placenta, spatially heterogeneous birefringence highlighted perivascular collagen arrangements. In skin, stronger phase retardation and depolarisation patterns were observed in dermal collagen bundles, with keloid scars showing markedly increased phase retardation (~ 1.4 radians) and depolarisation (~ 0.96), reflecting altered collagen density and disorganisation. QPM provides objective, spatially-resolved tissue anisotropy metrics, overcoming the qualitative limitations of traditional histological techniques. This approach offers a robust framework for assessing collagen remodelling in various pathological contexts.

Molecular mechanism of gallium nitrate in inhibiting bacterial biofilm formation through pykF modulation

Purpose Gallium nitrate, a non-redox analog of iron (III), suppresses bacterial biofilms and virulence within the framework of bacterial regulation. This study investigates the molecular mechanisms and regulatory pathways through which gallium nitrate modulates bacterial activity and function. Methods The antimicrobial properties of gallium nitrate, its effects on bacterial biofilms, and gallium-responsive signaling pathways were assessed. Observation of marked upregulation of pyruvate kinase ( pykF ) expression following gallium nitrate exposure prompted in vitro and in vivo experiments to examine how gallium influences the expression, enzymatic activity, and functional role of bacterial pykF . Results Crystal violet staining, XTT assay, confocal laser scanning microscopy, and scanning electron microscopy consistently indicated that gallium nitrate suppressed bacterial biofilm formation and metabolic activity. Transcriptomic profiling and subsequent validation analyses further suggested a strong association between pykF and gallium-mediated antibacterial effects. Both in vitro and in vivo experiments revealed that pykF knockout significantly enhanced bacterial survival and biofilm formation. Conclusion Gallium nitrate modulates bacterial biofilm development and virulence, with its antimicrobial effect largely dependent on pykF upregulation. Concurrent therapeutic targeting of both pykF and gallium may provide a more effective strategy against persistent biofilm-associated infections. This work also establishes a mechanistic basis for clinical approaches aimed at reducing biofilm formation and limiting device-related infections.

Clinical, radiological, and CSF features distinguishing spinal dural arteriovenous fistula from idiopathic transverse myelitis and seropositive NMOSD-/MOGAD-associated myelopathy: a retrospective observational study

Serious game prototype for nurses on nipple-areolar lesions resulting from fungal infections in breastfeeding

Background Despite the advantages, breastfeeding can be a difficult and painful process, especially due to the occurrence of nipple-areolar lesions due to fungal infection. Objective: Develop and validate a breastfeeding software program using a game to be used as an educational tool. Methodology An educational software program, the serious game “AleitaGame”, was developed through applied, methodological, quantitative and cross-sectional research. Clinical cases were constructed through a Scoping Review and the media resources and content were chosen. The software, the narrative, the clinical aspects and the context were then validated by experts. Results The construction of the clinical case presented and the scenario of a nipple-areolar lesion resulting from a fungal infection was based on 40 scientific documents. The product was then evaluated by two groups of judges. Conclusion The study allowed the development and validation of the prototype of serious game on nipple-areolar lesions resulting from fungal infections. The game covers historical content, anamnesis and relevant clinical parameters, the game received good evaluation scores from the judges and it is expected that at the end the player will recognize a nipple-areolar injury, identify signs and symptoms and carry out treatment, monitoring and prevention.

Pro-tumoral Ca2+ signaling is dependent on Slowpoke and Ca-α1T channels in Drosophila melanogaster glioma

Changes in U.S. medical school conflict of interest policies from 2014 to 2023

Background Concerns about the influence of the pharmaceutical industry on medical education, ranging from education of students to professional development, have led professional societies to recommend regulation of interactions between industry and medical schools. The objective of this study was to evaluate conflict of interest (COI) policies at medical schools in 2023 compared to 2014. Methods This study used a cross-sectional design to evaluate the COI policies at the top 30 medical schools identified by US News and World Report rankings. The authors collected policies by survey and review of public websites, and assessed their quality across 15 domains informed by guidelines published by leading national organizations and previous PharmFree Scorecards. Each domain was graded on a 3-level scale derived from professional organization guidelines, which when totaled corresponded to the following letter grades: an “A” (score 38–45), “B” (32–37), “C” (25–31), and “I/F” (< 25). This study assessed industry payments to school leadership using the 2023 Open Payments database. Results Eleven of thirty medical schools submitted COI policies, and the remainder were analyzed based on publicly available information. No school received an “A,” 22 (73.3%) schools received a “B”, 6 (20.0%) schools received a “C”, and 2 (6.7%) schools received an “I/F”. Most schools had model policies around COI enforcement (29/30, 96.7%), gift acceptance (25/30, 83.3%), and ghostwriting (24/30, 80.0%). No schools had model policies in limiting direct faculty payments. When comparing 2014 and 2023 Scorecards over the shared 14 domains, 14 (46.7%) schools had a decrease in score, 11 (36.7%) schools had an increase, and 5 (16.7%) schools had no change. Faculty at every school accepted industry payments, including 20 (16.7%) deans and 52 (19.3%) of clerkship directors. Conclusions Medical school COI policies remain less stringent than consensus recommendations; thus, renewed attention to policies and implementation is needed to ensure bias-free medical education.

Drug target mining and in silico screening of Tibetan plant metabolites for potential alleviation of Oroya fever, a neglected tropical disease

Structural characterization and antifungal properties of sequentially extracted polysaccharides from Algerian Opuntia ficus-indica L. cladodes

Opuntia ficus-indica L., a xerophytic cactus native to arid regions, is an understudied source of structurally varied polysaccharides with potential for bioactivity. Four different types of substances were separated in this study, which is the first time this method has been used for Algerian varieties: cellulose (19.1%), pectins (7.20%), hemicelluloses (2.57%), and water-soluble mucilage (8.84% of dry mass). Pectins rich in homogalacturonans (33.5% galacturonic acid) and rhamnogalacturonans (30% rhamnose) were identified by monosaccharide profiling, along with hemicelluloses that were dominated by xylose (55.9%). FTIR spectroscopy validated structural signatures, such as β-glycosidic linkages (890 cm ⁻ ¹) and carboxylate groups (1750 cm ⁻ ¹) in pectins. Penicillium sp . was shown to be dose-dependently inhibited by antifungal assays, with a 75% growth reduction at 100 mg/mL pectin concentration (*p* < 0.05 vs control). The structure of polysaccharides, especially the amount of carboxylate, is correlated with the observed bioactivity. Based on their biocompatibility and regional adaptability, these results establish Algerian O.ficus-indica polysaccharides as viable options for pharmaceutical and food preservation applications.

Reinforcement learning-based optimal control for stochastic opinion dynamics

Association of intraindividual differences in estimated glomerular filtration rates based on cystatin C and creatinine with dementia: A cohort study of the UK Biobank

Background Dementia is a leading cause of cognitive decline, with Alzheimer’s disease (AD) and vascular dementia (VaD) being the most common subtypes. The intraindividual difference between the estimated glomerular filtration rate based on cystatin C and creatinine (eGFR diff ) may serve as an indicator of the overall health status of an individual. However, the relationships between the eGFR diff and dementia risk, dementia subtypes, dementia-related neuroimaging changes, and cognitive functions remain unclear. Methods This study analysed data from over 450,000 participants in the UK Biobank who were followed for up to 15 years. The estimated glomerular filtration rate based on cystatin C (eGFR cys ) and creatinine (eGFR cr ) was calculated using the CKD-EPI equation, and eGFR diff was defined as the difference between these values (eGFR diff  = eGFR cys  − eGFR cr ). Multivariate Cox regression models were used to evaluate the associations between the eGFR diff and all-cause dementia (ACD), AD, and VaD, whereas cross-sectional analysis were used to examine the relationship among the eGFR diff , dementia-related neuroimaging changes, and cognitive functions. Results Over a median follow-up of 13.5 years, 8,710 participants developed dementia, including 3,910 with AD and 1,893 with VaD. Each one standard deviation increase in eGFR diff was associated with a reduced risk of dementia, with hazard ratios (95% confidence intervals) of 0.92 (0.90–0.94) for ACD, 0.94 (0.91–0.98) for AD, and 0.90 (0.85–0.94) for VaD. A negative eGFR diff was associated with adverse neuroimaging changes, including lower total brain and gray matter volumes and higher white matter hyperintensities. Additionally, a negative eGFR diff was associated with poorer performance across multiple cognitive domains. Conclusion A negative eGFR diff was associated with an increased risk of dementia, adverse neuroimaging outcomes, and cognitive decline. These findings suggest that the eGFR diff might be considered a potential associative indicator for dementia and cognitive impairment, suggesting potential clinical value in risk assessment and early intervention strategies.

Cerium and samarium doped TiO2 for degradation of crystal violet dye in wastewater by photo-degradation method

Abstract Crystal Violet is a toxic dye commonly found in wastewater from textile and printing industries. It is harmful to both the environment and human health due to its non-biodegradable and carcinogenic nature. Removing such dyes from water is a major challenge. In this study, we used a process called photocatalysis, where light energy helps to break down harmful chemicals, to degrade Crystal Violet dye. Titanium dioxide (TiO₂), a well-known photocatalyst, was used as the base material. To improve its efficiency, we added small amounts of two rare earth elements Cerium (Ce) and Samarium (Sm) to the TiO₂ structure. The doped TiO₂ photocatalysts were prepared using the co-precipitation method, which allows for even distribution of the dopant metals in the material. After synthesis, the materials were analyzed using different techniques to understand their crystal structure, surface properties, light absorption, and electron movement during the reaction. Photocatalytic activity was tested under UV light to evaluate how effectively the materials could degrade Crystal Violet. We studied the effects of various factors such as catalyst amount, dye concentration, solution pH, and light exposure time. The results showed that both Ce- and Sm-doped TiO₂ performed significantly better than undoped TiO₂. Over 90% of the dye was removed in a short time, with samarium-doped TiO₂ showing slightly better results than cerium-doped TiO₂ due to better electron trapping and redox properties. This study suggests that doping TiO₂ with rare earth metals is a promising and eco-friendly method for treating dye-contaminated wastewater.

Long-term prognostic value of microvascular obstruction by cardiac magnetic resonance in ST-segment elevation myocardial infarction

Aims Microvascular obstruction (MVO) portends a higher risk of remodelling and adverse events following ST-segment elevation myocardial infarction (STEMI). However, data regarding the implications of MVO in STEMI beyond five years of follow-up are scarce. Methods & Results This is a pooled analysis of three observational studies including 876 prospectively enrolled reperfused first STEMI patients, who underwent cardiac magnetic resonance imaging with late gadolinium enhancement (LGE), between 2003–2019. Median follow-up duration was 6.3 (IQR 3.6–9.3) years. The primary outcome was all-cause mortality. The secondary outcome was a combined endpoint of all-cause mortality and recurrent ischemic events (i.e., myocardial infarction or stroke). We performed Cox regression analyses with a time-dependent covariate. The study population consisted of 876 patients, mean age 59 years ± 12, 720 men (82%). MVO was present in 499 patients (58%). The presence of MVO was independently associated with all-cause mortality up to six years post-STEMI (Hazard Ratio [HR] 2.23, 95% CI 1.09–4.57, p = 0.029), but not after six years post-STEMI (HR 0.98, 95% CI 0.45–2.12, p = 0.958). Presence of MVO was not significantly associated with a combined endpoint of all-cause mortality and recurrent ischemic events before or after six years of follow-up (HR 1.27, 95% CI 0.81–1.99, p = 0.294 and HR 0.68, 95% CI 0.35–1.31, p = 0.244, respectively). Conclusions In STEMI patients, the presence of MVO by cardiac magnetic resonance imaging is associated with a more than two-fold higher risk of all-cause mortality up to six years after the index event. This relation seems to dissipate beyond this time period.