Category: Nevin Manimala

BMC Emerg Med. 2026 Apr 7. doi: 10.1186/s12873-026-01574-z. Online ahead of print.

NO ABSTRACT

PMID:41947057 | DOI:10.1186/s12873-026-01574-z

G3 (Bethesda). 2026 Apr 6:jkag092. doi: 10.1093/g3journal/jkag092. Online ahead of print.

ABSTRACT

Mutation is the fundamental source of genetic variation, yet growing evidence shows that mutations are not uniformly distributed across genomes but are shaped by genomic architecture, DNA-repair dynamics, and environmental conditions. Here, we investigate fine-scale determinants of mutation distribution in the non-biting midge Chironomus riparius, an ecologically important freshwater insect widely used in ecotoxicology. We integrated mutation data from five independent studies, including spontaneous mutation-accumulation experiments and multigenerational exposure assays involving cadmium, benzo[a]pyrene, tyre and road wear particles, and varying generational time. In total, we analysed 420 single-nucleotide mutations mapped to the chromosome-scale C. riparius reference genome. Using a Bayesian modelling framework, we tested whether mutation density is (i) uniformly distributed, (ii) non-uniformly distributed, or predicted by (iii) distance to telomeres and centromeres, (iv) proximity to genes, or (v) distance to repetitive elements. Models were compared using a cross-validation method. We also quantified the proportion of mutations in exons and evaluated the synonymous vs. non-synonymous spectrum using BayesFactor in R. The best-supported model incorporated non-linear effects of genomic position and distance to genes, identifying proximity to coding regions as the dominant predictor of mutation rate. Mutation density increased with distance from genes, indicating strong protection of genic regions. A model including repetitive elements showed nearly equivalent support, suggesting that functional and structural features jointly shape mutational landscapes. Only 9.8% of mutations occurred in exons despite exons representing 22.85% of callable sites, demonstrating marked depletion of exonic mutations. Among exonic mutations, 70.7% were non-synonymous-statistically indistinguishable from the neutral expectation (75%). These findings show that mutation processes in C. riparius are strongly structured by genome architecture, with implications for evolutionary genomics, ecotoxicology, and population-genetic inference.

PMID:41947018 | DOI:10.1093/g3journal/jkag092

Nat Neurosci. 2026 Apr 7. doi: 10.1038/s41593-026-02255-7. Online ahead of print.

ABSTRACT

The brain must infer the state of the external world despite the inherent uncertainty of its sensory inputs and internal processes. Under conditions of heightened uncertainty, it increasingly relies on prior knowledge, derived from accumulated experience with the regularities and statistical structures of the environment. This principle has been formalized by Bayesian inference theories, which are supported by substantial evidence from both behavioral and neuroscience studies. However, direct evidence for the existence of prior knowledge in the brain, and for the encoding of environmental statistics by neural circuits, remains limited. Here we show that cerebellar circuits learn the prior probability distribution of temporal variables during eyeblink conditioning in mice and encode these representations in Purkinje cell simple and complex spike signaling. We further demonstrate that Purkinje cells are involved in eliciting predictive motor behaviors, such as the conditioned eyeblink response, that also reflect the statistics of the experimentally imposed prior distribution of the stimulus. Computational modeling of these results indicates the juxtaposition of counteracting long-term plasticity mechanisms by which cerebellar Purkinje cells could acquire prior knowledge that is shaped by the statistics of different probability distributions. Our results suggest that the cerebellar circuitry may be uniquely poised to learn the probability of events in the world and internalize these as prior knowledge. These findings advance understanding of how neural computations could implement Bayesian inference.

PMID:41946969 | DOI:10.1038/s41593-026-02255-7

NPJ Digit Med. 2026 Apr 7;9(1):289. doi: 10.1038/s41746-026-02470-3.

ABSTRACT

Atrial fibrillation (AF) is the most common sustained arrhythmia and a leading cause of ischemic stroke. Existing risk scores, such as CHA₂DS₂-VASc, offer limited predictive accuracy and fail to capture complex clinical patterns. To improve generalizability and clinical utility, we developed and externally validated clinically interpretable machine learning models using only age, comorbidities, and medication use to predict 1-year stroke risk in patients with newly diagnosed AF. Both logistic regression (LR) and Platt-calibrated extreme gradient boosting (XGB) models achieved high discrimination in internal (AUCs = 0.915 and 0.914) and external validation cohorts (AUCs = 0.877-0.886), significantly outperforming CHA₂DS₂-VASc (AUCs = 0.614-0.621; p < 0.001). Calibration curves and decision curve analysis confirmed strong clinical utility. Long-term follow-up demonstrated superior risk stratification and treatment responsiveness in LR-defined high-risk groups. These models provide accurate, individualized stroke risk estimates to guide direct oral anticoagulant (DOAC) initiation in real-world hospital settings.

PMID:41946928 | DOI:10.1038/s41746-026-02470-3

Sci Rep. 2026 Apr 7. doi: 10.1038/s41598-026-47471-0. Online ahead of print.

ABSTRACT

Almost half of under-five children in health facilities are febrile in sub-Saharan Africa. The non-specific clinical symptoms coupled with; limited diagnostics capacities, overlapping endemicity and the surveillance gaps complicates accurate cause identification of an acute febrile illnesses in resource limited settings. This challenge leads to misdiagnosis, overtreatment, and delays in appropriate management, increasing morbidity and mortality. Health systems are often overloaded, with providers attributing fevers to the most common pathogen, while other emerging infections are the cause. This study unpacked the febrile illness by testing for dengue fever in parallel to malaria. Febrile ill children below 5 years seeking health services public health facilities in Busia and Kisumu Counties were screened using an approved malaria and dengue fever rapid test kits at the outpatient department. Those who screened positive were recruited into the study. A total of 1004 children were screened, 380 met the recruitment criteria. 215 (21.4%) tested positive for P. falciparum alone, 90 (8.9%) tested positive for dengue fever alone while 75 (7.5%) had co-infections. Busia had the highest P. falciparum-only infection (23.4%) while Kisumu had the highest dengue-only infections (12.6%). Dengue fever is a re-emerging neglected tropical, climate change driven disease in malaria endemic regions. Other than creating awareness to build capacity for diagnosis, this study unmasked and confirmed dengue as a major contributor to the non malarial febrile illnesses among children. There is need to revise the screening algorithm for febrile patients to improve arboviral surveillance.

PMID:41946915 | DOI:10.1038/s41598-026-47471-0

Sci Rep. 2026 Apr 7. doi: 10.1038/s41598-026-47584-6. Online ahead of print.

ABSTRACT

To evaluate the effectiveness of combining problem-based learning with the flipped classroom (PBL-FC) teaching method in the “Ocular Trauma” module in ophthalmology education, specifically in enhancing clinical medicine students’ self-directed learning ability and empathy. A quasi-experimental study with a controlled educational intervention was conducted, and third-year clinical medicine students from eight classes were divided into PBL-FC (n = 43) and traditional groups (n = 44). Both groups were assessed before and after class using Self-Directed Learning Ability and Empathy Quotient (EQ)-40 scales. A comparison was also made between theoretical examination scores. The two groups showed no statistically significant differences (P > 0.05) in gender ratio, age, pre-class empathy scores or pre-class self-directed learning ability scores. After class, the PBL-FC group demonstrated significantly higher total self-directed learning ability scores (175.72 ± 16.20 vs. 156.19 ± 12.72) and scores across all sub-dimensions (P < 0.05). In addition, their empathy (46.91 ± 5.56 vs. 41.89 ± 5.61) and theoretical examination scores (77.81 ± 8.63 vs. 72.45 ± 10.55) were also substantially superior to those of the traditional group (P < 0.05). The combined PBL-FC teaching method is effective in enhancing undergraduate medical students’ self-directed learning ability, empathy and theoretical knowledge. This study provides empirical support for the reform of ophthalmology education.

PMID:41946914 | DOI:10.1038/s41598-026-47584-6

Eur J Clin Nutr. 2026 Apr 7. doi: 10.1038/s41430-026-01732-3. Online ahead of print.

ABSTRACT

BACKGROUND: India’s food consumption landscape has transformed over the past decade, with implications for nutrition security. This article quantifies changes in household expenditure, consumption patterns across major food groups, and dietary sources of selected micronutrients.

METHODS: Data from nationally representative Household Consumption Expenditure Surveys (HCES) 2011-12 and 2023-24 were analysed. Food quantities were standardised to adult female equivalents, and micronutrient intake was derived by linking food acquisition data to Indian Food Composition Tables. Models were fitted using a generalised additive mixed model with random effects (bam function, mgcv package in R).

RESULTS: Monthly per capita expenditure has increased across rural and urban areas, while share of food in household expenditure has declined, signalling economic diversification. Within food budgets, share of cereals has fallen sharply, particularly among poorest quintiles, consistent with expansion of food security programmes providing subsidised cereals. Meanwhile, probability and quantity of consumption of nutrient-dense foods- dairy, fruits, and flesh products, has risen across income groups, with larger gains among poorest households. Seasonal and regional disparities in perishable food consumption persist but have narrowed. Despite greater dietary diversity, micronutrient intake remains suboptimal. Estimated daily intake of Iron, Zinc, Calcium, and B Vitamins fell below Estimated Average Requirements for non-lactating adult women, with median inadequacy exceeding 75% for several micronutrients.

CONCLUSION: India’s dietary transition shows progress but persistent gaps. HCES-based estimates provide valuable insights, underscoring need for integrated strategies aligning food policy, social protection, and nutrition-sensitive interventions to improve equitable access to nutrient-dense foods and reduce micronutrient inadequacy.

PMID:41946892 | DOI:10.1038/s41430-026-01732-3

Ann Biomed Eng. 2026 Apr 7. doi: 10.1007/s10439-026-04130-9. Online ahead of print.

ABSTRACT

PURPOSE: Thick-walled vascular models, including block models, are increasingly used for in vitro investigations of fluid dynamics and endovascular device testing, particularly fatigue testing at high frequencies, as valuable alternatives to thin-walled models due to their simpler fabrication. Physiologically compliant models provide more realistic insights into hemodynamics and implant deformation; however, no compact and experimentally validated closed-form equation exists to predict the volumetric compliance of thick-walled vessel models.

METHODS: A closed-form mathematical equation was derived to estimate the volumetric compliance of thick-walled cylindrical vessel models. The equation was experimentally validated through static compliance tests on cylindrical vascular models of varying wall thicknesses fabricated from two silicone elastomers and polyvinyl alcohol hydrogel (PVA-H) with four PVA concentrations (10, 12, 14, and 16 wt/vol.%). Dynamic compliance tests were performed at 1, 5, 10, and 30 Hz to assess the viscoelastic behavior of the materials. Finally, an applicability study was performed by fabricating block-form anatomical aneurysm models targeting physiological volumetric compliance based on the predicted equation.

RESULTS: Predicted and measured values showed strong agreement (R² > 0.95). PVA-H-10 exhibited volumetric compliance within the physiological range (0.4-1.1%/mmHg). Volumetric compliance decreased by over 50% at 30 Hz, confirming viscoelastic behavior with a maximum loss to storage volumetric compliance ratio of 0.14. Measured aneurysm model compliance matched predictions with an error below 7%.

CONCLUSION: This study provided a validated mathematical and experimental framework for fabricating thick-walled vascular models with physiologically relevant volumetric compliance and viscoelasticity for fluid dynamics and endovascular device testing.

PMID:41946863 | DOI:10.1007/s10439-026-04130-9

Cogn Affect Behav Neurosci. 2026 Apr 7. doi: 10.3758/s13415-026-01423-3. Online ahead of print.

ABSTRACT

Pupil dilation responses are reliable physiological markers of arousal in response to unexpected events. We investigated how these responses generalise across different sensory modalities by using transitions between regular and random sequences of visual dots and auditory tones. In Experiment 1, we investigated sequences of visual dots and found that (a) transitions from a regular sequence to a random sequence induced pupil dilations, (b) transitions from one regular sequence to another regular sequence also induced pupil dilations, and (c) transitions from a random sequence to a regular sequence did not reliably induce them. In Experiment 2, we replicated these findings, confirming their reliability and thereby generalizing the literature from the auditory to the visual modality. In Experiment 3, we directly compared pupil dilations in visual and auditory modalities. We observed strong cross-modal similarity in pupil sizes, particularly for transitions between regular and random sequences. We also decomposed the pupil size time series to approximate phasic pupil dilation events. While the patterns of dilation events were quite similar, differences between modalities in dilation size (but not in rates) occurred during transitions from one regular to another regular sequence. Overall, our findings suggest that pupil-linked arousal reflects inference of statistical structure and its violations, exhibiting substantial (albeit not perfect) similarity across modalities.

PMID:41946847 | DOI:10.3758/s13415-026-01423-3

J Clin Sleep Med. 2026 Apr 7;22(1):44. doi: 10.1007/s44470-026-00066-y.

ABSTRACT

PURPOSE: Examine associations between sleep patterns (duration, timing, and regularity) and weight status and explore moderating effects of parenting/family functioning among children with mild sleep-disordered breathing (SDB) from the Pediatric Adenotonsillectomy Trial for Snoring.

METHODS: Two age groups (3-5 and 6-12-year-olds) were examined separately with waist circumference (WCz) and body mass index (BMIz) z-scores as the primary and secondary endpoints, respectively.

RESULTS: Participants were 207 younger and 252 older children in a socio-demographically diverse sample. In adjusted models with older children, shorter sleep was associated with higher WCz, controlling for weekend mid-sleep timing (coefficient estimate beta = – 0.137, p = 0.027) with a similar finding for BMIz (beta = – 0.144, p = 0.041); later timing was related to higher WCz, controlling for sleep duration (beta = 0.122, p = 0.032). Shorter sleep duration was associated with higher WCz among the older children with greater parental distress (interaction p = 0.005), parent-child dysfunctional interactions (interaction p = 0.020), and less authoritative parenting (interaction p = 0.023) compared to those with more optimal parent-child relationships. There were no statistically significant associations or interactions among younger children.

CONCLUSIONS: In school-aged children, shorter sleep duration and later midpoint, but not social jet lag, tended to be associated with weight status. When mutually adjusting for duration and midpoint, a stronger statistically significant association was observed. Children subject to less optimal parenting practices were at the greatest risk of shorter sleep. Accounting for sleep timing and parenting factors that might further increase children’s biological propensity for obesity is recommended in future studies in this area.

CURRENT KNOWLEDGE/STUDY RATIONALE: Initial evidence suggests that shorter sleep duration and sleep-disordered breathing (SDB) increase the risk of becoming overweight in later childhood. This study examined relationships of additional sleep patterns-timing and regularity-and possible moderating effects of parenting/family factors using a well-characterized cohort of children with mild SDB from the Pediatric Adenotonsillectomy Trial for Snoring.

STUDY IMPACT: This study demonstrates that both shorter sleep duration and later timing relate to higher waist circumference and body mass index z-scores among school-aged children. Parenting factors (i.e., stress, parent-child dysfunctional relationships, and less use of an authoritative parenting style) may moderate sleep pattern-weight status relationships and therefore identify children most vulnerable to obesity because of insufficient sleep.

PMID:41946844 | DOI:10.1007/s44470-026-00066-y