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Humanity spoke thousands of languages at the dawn of farming — now many of them are lost

What The Odyssey reveals about ancient science — from botany to psychiatry

International PhD students to face strict limits on time in the US

Myocardial microvascular patterns in histological sections from patients with and without type 2 diabetes

Type 2 diabetes is associated with small vessels dysfunction. This study assessed whether type 2 diabetes is associated with changes in the myocardial capillary pattern in two-dimensional histological sections as an indirect proxy for the three-dimensional network in the myocardium. We used myocardial samples from the left and right ventricles harvested during cardiac surgery (N = 53; 44 without and 9 with type 2 diabetes). We prepared histological sections with CD34-immunostained endothelium. We used cross-sections through the small vessels as points for two methods of point-pattern analysis: Voronoi-based analysis and fractal-based analysis. We were unable to detect differences in the microvascular pattern on myocardial sections of participants with and without type 2 diabetes.

Daily briefing: Orcas smash sunfish to smithereens

Machine learning–optimized discharge timing in typhoid care: Implications for clinical outcomes, cost efficiency, and health system performance

Objective To develop and validate a machine learning model identifying typhoid fever patients at risk of unnecessarily prolonged hospitalization, and to quantify the clinical, financial, and systemic consequences of model-guided discharge optimization in a fragmented, multi-payer public insurance system. Setting Iran Health Insurance Organization inpatient claims for typhoid fever, all provinces, 2024–2025; 80,223 raw claims aggregated into 13,105 hospitalization episodes. Design Retrospective observational study with embedded computational modelling. A gradient-boosted classifier was developed on administrative claims and validated through stratified five-fold cross-validation. Predictions were translated into clinical, financial, and systemic impact levels. Results The model achieved an area under the receiver operating characteristic curve of 0.862, outperforming logistic regression (0.831). Among 13,105 episodes, 4,658 patients were identified as potentially having reducible length of stay, projecting 6,459 potentially recoverable bed-days pending clinical review. Restricted to 5,784 inpatient admissions, optimized discharge timing reduced total expenditure by 22.9% (USD 1,306,306, purchasing power parity-adjusted); 75.0% of savings accrued to patients as reduced out-of-pocket payments and only 25.0% to the insurer, reflecting a mean insurance coverage rate of 27.7% for this care pathway. Freed capacity could accommodate 1,328 additional admissions without infrastructure expansion. Public hospital patients and those aged 60 years and above showed the greatest benefit, with out-of-pocket reductions of 43.8% and 35.5% respectively. The strongest predictor of prolonged stay was payer-classification status rather than any clinical variable, revealing a structural misalignment between insurance administration and discharge practice. Conclusion Machine learning applied to routine insurance claims can reliably flag patients for clinical discharge review and quantify multi-dimensional system impacts. Discharge optimization in typhoid care functions primarily as a patient financial protection intervention, and should be prioritized in public hospitals and among elderly patients where financial vulnerability and optimization potential are both greatest.

Urinary podocalyxin as an early biomarker for diabetic nephropathy

Background Conventional biomarkers, such as the urinary albumin-to-creatinine ratio (uACR), detect diabetic nephropathy (DN) late in its course and may miss early podocyte injury. Urinary podocalyxin (u-PDX), a sialylated glycoprotein shed from podocytes, may offer an earlier means of detection. Methods We conducted a cross-sectional analytical study at Bangabandhu Sheikh Mujib Medical University between March 2023 and August 2024. Eighty-eight adults were enrolled: 59 participants with type 2 diabetes mellitus (T2DM) and 29 healthy controls. Participants with diabetes were stratified into normoalbuminuric (n = 29), microalbuminuric (n = 15), and macroalbuminuric (n = 15) subgroups based on uACR. Clinical variables and biochemical indices were recorded. u-PDX concentrations were measured using ELISA, and associations with uACR and eGFR were analyzed using Kendall’s tau-b and Pearson’s correlation coefficients. Diagnostic performance was assessed using receiver operating characteristic (ROC) curves with bootstrap internal validation. Results Among participants with diabetes, u-PDX levels increased progressively across normo-, micro-, and macroalbuminuric groups (p < 0.001). u-PDX correlated positively with fasting blood glucose, post-glucose plasma glucose, HbA1c, serum creatinine, serum urea, and uACR, with the strongest correlation for uACR (r = 0.79, p < 0.001), and inversely with serum albumin (r = −0.62, p < 0.001) and eGFR (r = −0.51, p < 0.001). In pairwise ROC analysis, a u-PDX cutoff of 0.80 ng/mL discriminated healthy controls from diabetic patients without albuminuria (sensitivity 100.0%, specificity 96.4%); 1.60 ng/mL discriminated diabetic patients without albuminuria from those with microalbuminuria (86.7%, 93.1%); and 5.51 ng/mL discriminated microalbuminuric from macroalbuminuric patients (86.7%, 93.3%). For overall discrimination of albuminuria-defined DN among diabetic patients, the optimal u-PDX cutoff was 2.92 ng/mL (AUC 0.96, 95% CI 0.90–1.00). Conclusions Urinary podocalyxin is a sensitive early biomarker of diabetic nephropathy, rising before overt albuminuria and correlating with albuminuria severity and declining eGFR. However, longitudinal validation is required before u-PDX can be recommended for routine screening in adults with T2DM.

Expression of Concern: Molecular prevalence, phylogeny and hematological impact of Toxoplasma gondii and Plasmodium spp. in common quails from Punjab, Pakistan

Identification of Candidate epitopes from nation-enriched sequences in the African swine fever virus genomes

African swine fever virus (ASFV) is a highly lethal pathogen that causes African swine fever (ASF) and is found in Africa, Europe, and Asia. In addition, extensive regional genetic variation poses significant challenges for vaccine development. In this study, we aimed to identify amino acid sequence fragments that are commonly enriched within ASFV strains from each country and evaluate their potential as epitopes. Amino acid sequences of genomes were segmented into overlapping 9-, 12-, 15-, and 20-mer peptides; selected fragments enriched in countries with at least ten available genomes; and cytotoxic T lymphocyte (CTL), helper T lymphocyte (HTL), and linear B lymphocyte (LBL) epitope predictions, followed by antigenicity assessment. Genomes from Italy yielded the highest number of fragments across all peptide lengths, whereas those from Russia showed a unique pattern in which fragment counts decreased as peptide length increased. From the five countries analyzed, 136 CTL, 95 HTL, and 97 LBL candidate epitopes were identified, of which 39 CTL, 18 HTL, and 75 LBL epitopes were predicted to be antigenic. The identified epitopes originated from structural ( n  = 24), replication/transcription ( n  = 11), and multigene family ( n  = 38) proteins. The resulting epitope library provides a comprehensive resource for the selection of multi target vaccines and diagnostic candidates. These findings provide a foundation for the design of region-specific vaccines and can be broadly applied for the future development of ASFV vaccines and diagnostic tools.

Towards a behavioral profile of degree adverbs in Mainland and Taiwan Mandarin news language

The major difference between Mainland Mandarin and Taiwan Mandarin in adverb usage lies in degree adverbs. Exploring the similarities and differences in degree adverbs across both sides of the strait not only helps reveal the subtle differences between Chinese dialectal varieties, but also helps broaden the path for computer-assisted compilation of language dictionaries, and enlighten the research method used by language variation studies, comparative language studies and other applied linguistics. This paper compares degree adverbs in Mainland Mandarin and Taiwan Mandarin based on self-built news corpus by using BP (behavior profile) approach and finds that: (1) Degree adverbs with high and medium intensification/mitigation level are more commonly used while degree adverbs with extreme and low intensification/mitigation level are avoided on both sides. In addition, Taiwan uses more extreme degree adverbs than Mainland. (2) The usage of degree adverbs in Mainland and Taiwan Mandarin is significantly related to the semantic prosody, word class, and syntactic function of the words they modify. Specifically, in terms of the semantic prosody of the words they modify, degree adverbs in Mainland modify more positive semantic prosody than those in Taiwan. In terms of the word class of the words they modify, degree adverbs in Mainland mostly modify verbs while degree adverbs in Taiwan corpus mostly modify adjectives. In terms of the syntactic function of the words they modify, degree adverbs in Mainland mostly modify predicates while degree adverbs in Taiwan mostly modify attributives. (3) Cluster diagram analysis shows that the unique degree adverbs on both sides can be substituted with degree adverbs that have similar behavioral profile by each other, which reflects the openness and flexibility of language. This article further points out that the similarities and differences between degree adverbs in Mainland and Taiwan are mainly influenced by news language norms, regional socio-cultural differences, and language change and contact. This paper aims to provide new insights for language users regarding the subtle differences between dialectal varieties in news language and beyond, thereby facilitating more effective communication and the appropriate language use.

Polio should have been eradicated by now. What’s plan B?

Behavioural and emotional assessment of Malaysian adolescent boys with congenital colour vision deficiency and its association with socioeconomic factors

Congenital colour vision deficiency (CCVD) is associated with challenges in daily functioning and social interactions, yet its behavioural and emotional implications during adolescence remain underexplored. This study aimed to compare behavioural and emotional problems between adolescent boys with CCVD and those with normal colour vision (NCV) and to examine the influence of socioeconomic factors. A school-based cross-sectional comparative study was conducted where 44 boys with CCVD and 44 age- and class-matched NCV controls (aged 13–16 years) were identified through school-based vision screening. Colour vision status was confirmed using the Ishihara and Farnsworth D15 tests. Their parents completed the Child Behaviour Checklist (CBCL/4–18) to assess Internalising Problems, Externalising Problems , and Total Problems , as well as narrow-band syndromes. Data were analysed using Mann–Whitney U tests and chi-square analyses. Adolescents with CCVD scored significantly higher on most CBCL/4–18 narrow-band scales ( Anxious/Depressed, Withdrawn, Thought Problems, Attention Problems, Delinquent Behaviour, Aggressive Behaviour ), broad-band scales (Internalising Problems and Externalising Problems ), and Total Problems (all q < 0.05). Attention Problems showed the strongest association with CCVD status. Categorical analysis revealed that CCVD status was significantly associated with classification in the Borderline Clinical/Clinical range for Externalising Problems, Attention Problems, Anxious/Depressed, Aggressive Behaviour , and Total Problems . Among boys with CCVD, those whose parents had tertiary education demonstrated higher proportions of behavioural difficulties in the Externalising Problems and Total Problems domains; however, these findings should be interpreted with caution due to the small subgroup size. Lower household income was significantly associated with Withdrawn, Anxious/Depressed, Thought Problems, and Aggressive Behaviour scores (all q < 0.05). In conclusion, the results indicate that psychosocial and environmental factors may influence behavioural outcomes in children with CCVD, highlighting the importance of early identification and supportive interventions.

Integrated machine learning for cause-of-death classification and postmortem interval prediction: Liver and kidney metabolomics from seawater-immersed rat cadavers

Purpose To assess whether liver and kidney metabolomics combined with machine learning can distinguish seawater drowning from postmortem submersion after CO 2 euthanasia and estimate postmortem interval (PMI) under controlled conditions. Methods Sixty male Sprague–Dawley rats were assigned to a seawater-drowning group or a postmortem-submersion group after CO 2 euthanasia (30 per group). Liver and kidney tissues were collected at 0, 12, 24, 36, 48, and 72 h after death and analyzed by untargeted LC–MS/MS. Principal component analysis (PCA) and cross-validated orthogonal partial least squares discriminant analysis (OPLS-DA) were used to characterize global metabolic variation. Random Forest (RF), Support Vector Machine (SVM), Multi-Layer Perceptron (MLP), and Gradient Boosting Decision Tree (GBDT) were evaluated using repeated 10-fold cross-validation (five repeats; 50 folds in total). PMI-specific XGBoost models used 20 metabolites selected within each training fold by absolute Spearman correlation and were assessed by repeated 10-fold and leave-one-time-point-out cross-validation. SHAP analysis summarized feature contributions. Results PCA showed that dominant metabolic variation was mainly associated with PMI, with substantial overlap between the two groups in the PC1–PC2 space. Cross-validated OPLS-DA identified group-associated structure in liver and kidney, with Q 2 (cum) values of 0.847 and 0.723, respectively. Mean classification AUCs ranged from 0.973 to 0.996 in liver and from 0.931 to 1.000 in kidney. Under repeated 10-fold cross-validation, the liver and kidney PMI models achieved MAEs of 4.78 and 4.05 h and R 2 values of 0.823 and 0.892, respectively. Under leave-one-time-point-out cross-validation, MAEs increased to 13.52 and 13.64 h, while R 2 values were 0.587 and 0.592. SHAP analysis showed partly different metabolite contribution patterns between the two organs. Conclusion In this controlled rat model, liver and kidney metabolomic profiles combined with machine learning supported discrimination between seawater drowning and postmortem submersion after CO 2 euthanasia and captured PMI-related metabolic changes. The classification models, PMI-specific XGBoost regression models, and SHAP analyses characterized organ-specific metabolite patterns associated with discrimination between the two modeled conditions and PMI prediction.

Single-cell transcriptomic analysis reveals the immunosuppressive status of NK cell subpopulations in TNBC

Triple-negative breast cancer (TNBC), lacking expression of the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), has clinical features that include high invasiveness, limited response to current immunotherapies, heightened risk of recurrence, and poorer overall prognosis. Central to these adverse clinical outcomes is the tumor microenvironment (TME), where the presence of immature natural killer (NK) cells with lower cytotoxic capacity has been associated with disease progression. Through a comprehensive analysis of publicly available single-cell transcriptomic data from breast cancer, we identified three NK cell subtypes within TNBC and non-TNBC tissues, named NK_XCL1, NK_FCGR3A, and NK_ISG15. Compared to non-TNBC, the presence and cytotoxic activity of NK_FCGR3A cells in TNBC were markedly diminished, primarily due to a substantial increase in the expression of inhibitory receptors like NKG2A (KLRC1). NK_ISG15 cells in TNBC show higher expression of type I interferon signaling genes. Through cell-type cross-talk analysis, we found that the feature of NK_FCGR3A cells in TNBC was mediated by myeloid cells with the HLA-E-KLRC1/HLA-E-CD94:NKG2A signal pathway. Notably, through integrating with public cancer transcriptomic data, we found higher expression of ISG15 is associated with poor prognosis, while higher expression of NK_FCGR3A signature genes is correlated with favorable prognosis. Collectively, these findings and the markers identified offer valuable insights into the mechanisms of immune evasion in TNBC, underscoring potential targets for developing therapeutic strategies that may improve patient outcomes.

Assessment of trends and determinants of under-five mortality among children born to older women: Evidence from Ethiopian demographic and health surveys

Introduction Under-five mortality has long been used as an indicator of the level of socio-economic development of a country. Global attention has been given to the issue through the Sustainable Development Goals, yet the burden continues to be disproportionately concentrated in Sub-Saharan Africa and South Asia. Ethiopia is one of six nations that together account for half of global under-five mortality, with particular burden observed among children born to older mothers. Hence, this study aimed to determine the magnitude of under-five mortality among children born from elder mothers, assess its trend over time, and identify associated factors. Methods Data were drawn from the nationally representative Ethiopia Demographic and Health Surveys (EDHS) conducted in 2000, 2005, 2011, and 2016. The analytic sample comprised 6,199 children born to women aged 35–49 years in the five years preceding each survey. Information on mother and child characteristics, socio-economic factors, and environmental variables was collected through face-to-face household interviews. Descriptive statistics characterized the study participants. Multilevel binary logistic regression was used to estimate adjusted odds ratios and 95% confidence intervals for factors associated with under-five mortality. Result Under five mortality declined from 128 per 1000 live births during the year 2000–56 per 1000 live births in 2016. This study identified several factors contributing for under-five mortality among children of women aged 35–49 years. Protective factors included female child sex (AOR = 0.65, 95% CI: 0.53–0.79), maternal age at first birth of 31–40 years (AOR = 0.34, 95% CI: 0.11–0.98), family size of 6–10 members (AOR = 0.18, 95% CI: 0.14–0.24), birth interval greater than 3 years (AOR = 0.35, 95% CI: 0.26–0.47), and 1–3 antenatal care visits (AOR = 0.65, 95% CI: 0.50–0.84). In contrast, the following factors increased the odds: twin birth (AOR = 6.15, 95% CI: 3.94–9.60), four births in the last five years (AOR = 2.64, 95% CI: 1.15–6.06), nine or more children ever born (AOR = 3.79, 95% CI: 2.10–6.84), and maternal age at birth of the index child of 45–49 years (AOR = 2.13, 95% CI: 1.55–2.93). Conclusion The decline in under-five mortality over the last 16 years in Ethiopia represents promising progress toward the targets set out in the Sustainable Development Goals and national health policy. However, targeted programs and interventions focusing on provision of the recommended antenatal care, adequate birth spacing, limiting the number of births within short intervals, discouraging pregnancies after age 40, and supporting smaller family sizes are essential to further reduce under-five mortality. The study findings highlight the importance of risk-pregnancy screening, well-spaced pregnancies, family health promotion, and strengthened childhood illness prevention and treatment services.

Analysis of mechanical properties and micro-mechanisms of concrete based on the method of using steel slag as aggregate replacement: Macro-mechanical tests and microscopic tests of four typical control groups

There is still controversy over whether the mechanical properties of steel slag concrete are superior to those of ordinary crushed-stone concrete and which method of substituting steel slag for aggregates yields better mechanical performance. Four groups of specimens were designed in this study, namely ordinary crushed-stone concrete, coarse steel-slag natural-sand concrete, crushed-stone fine steel-slag concrete, and all-steel slag concrete. The compressive strength, flexural strength, splitting tensile strength and failure morphology of the four groups of specimens were tested. Meanwhile, microhardness, scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy tests were conducted to analyze the differences in their mechanical properties from a microscopic perspective. The corresponding test results indicated that: (a) Under the test conditions of this study, the order of compressive strength, flexural strength, and splitting tensile strength of concrete is ordinary crushed-stone concrete < coarse steel-slag natural-sand concrete <crushed-stone fine steel-slag concrete < all-steel slag concrete. (b) Steel slag fine aggregates are superior to steel slag coarse aggregates in enhancing the mechanical properties of concrete. Crushing steel slag coarse aggregate into steel slag fine aggregate to replace ordinary fine aggregates is more effective in enhancing mechanical strength than directly using coarse steel slag to replace coarse aggregates. When steel slag simultaneously substitutes for both coarse and fine aggregates, the concrete strength is the highest. Despite limitations of this study, the above conclusions, if further validated by future studies, will provide valuable references for further research on steel slag concrete.

Three tips to avoid AI image mistakes in science

The impact of political ideologies on cultural erosion: Indigenous education policy in Brazil (2009–2022)

Indigenous schools in Brazil aim to provide equitable education to both Indigenous and non-Indigenous communities. As of 2022, there were 3,411 such schools operating nationwide, serving the entire Indigenous population. However, an analysis of educational data reveals significant non-compliance with legislation designed to integrate Indigenous culture into the curriculum. Our research demonstrates that the school system frequently falls short of its legal obligation to promote and safeguard Indigenous cultural values. The systematic suppression of culturally specific materials and native languages is particularly alarming and appears to be associated with the influence of far-right political administrations. This study analyzes school census data from 2009 to 2022, employing chi-square tests, Cramer’s V tests, descriptive statistics and for robustness hierarchical mixed models to examine the relationship between political ideology and educational practices.

Optimal exercise modalities and dosages for improving depression in middle-aged and older adults with Parkinson's disease: A Bayesian Dose–response network meta-analysis

Objective To characterise the dose response relationship between exercise and depressive symptoms in middle aged and older adults with Parkinson disease using a continuous modelling framework and to compare structural differences across exercise modalities. Methods PubMed, Embase, Web of Science, Cochrane Library and APA PsycINFO were searched to 19 February 2026. Exercise dose was standardised as MET-minutes per week. A Bayesian network meta-regression model was used to estimate continuous dose–response relationships. Evidence certainty was assessed using GRADE. Results Twenty-five RCTs were included. Overall exercise dose showed a significant non-linear association with reduced depressive symptoms in middle-aged and older adults with Parkinson disease. Beneficial effects were sustained between 110 and 890 MET-minutes per week, peaking at 560 MET-minutes per week (effect size 0.48, 95% credible interval 0.22–0.80), with an optimal range of 440–670 MET-minutes per week. Effects were not stable at 1000 MET-minutes per week. Modality analyses indicated that exercise combined with cognitive training and mind–body exercise demonstrated consistent benefits within moderate to moderately high dose ranges, both peaking at 560 MET-minutes per week. Aerobic cycling, functional training, and multicomponent training showed no stable significant dose range, whereas walking reached significance only at ≥670 MET-minutes per week with wide credible intervals. Conclusion Exercise in middle-aged and older adults with Parkinson disease and comorbid depression exhibits a structured non-linear dose–response pattern with a defined optimal range, and modality-specific differences indicate that therapeutic effects depend on both quantitative dose and qualitative task characteristics, providing a quantitative basis for precision exercise prescription.

Experimental and numerical studies on heat exchange between slag/metal particles and air inside countercurrent cyclone heat exchanger for recovering waste heat from molten slags in dry and centrifugal granulation process

In dry and centrifugal granulation of molten slags with heat recovery, the heat exchange efficiency between high-temperature particles and the cold air directly determines the efficiency of waste heat recovery. However, the heat transfer characteristics between pure slag particles granulated from blast furnace slag and air and between a mixture of slag and metal particles granulated from steelmaking slag and air in complex flow fields still remain unclear. Therefore, this study employs a combined approach of experiment and numerical simulation to comparatively investigate the heat transfer behavior of pure slag particles and mixtures of slag and metal particles in a countercurrent cyclone heat exchanger. The investigation results indicate that the heat exchanger exhibits optimal heat transfer performance under specific operating conditions, with the maximum heat exchange efficiencies being 80.0% for pure slag particles and 77.0% for a mixture of slag/metal particles produced from steelmaking slag. Both experimental and numerical simulation results indicate that metallic iron particles produced from granulation of steelmaking slag lowers the heat exchange efficiency; when the metallic iron content in the slag increases from 2.5% to 10% by weight, the heat exchange efficiency drops from 77.0% to 73.0%. The numerical simulation results further reveal that the spatial distribution of particles within the heat exchanger is a key factor determining the overall heat exchange efficiency. The results provide a theoretical basis for design and operation optimization of industrial countercurrent cyclone heat exchangers for waste heat recovery from molten slags in dry and centrifugal granulation process.