Browse Articles

Darkness and body size shaped end-Cretaceous marine extinction patterns

Abstract The Chicxulub asteroid impact at the Cretaceous–Paleogene (K–Pg) boundary (66 Ma) is thought to have caused the extinction of around 75% of species in the fossil record by triggering catastrophic environmental changes 1 . However, despite decades of research, the mechanisms linking the environmental changes to the selective extinction patterns observed in the marine fossil record remain unresolved. Here we use a global trait-based ecosystem model 2,3 to establish this causality for the marine plankton community beyond the fossilized groups. Our model simulates diversity dynamics during the initial 100 years after the K–Pg boundary and represents explicitly extinction based on biomass thresholds that scales with body size. Under K–Pg climatic forcings, the model reproduces successfully key observed extinction patterns, including the high vulnerability of planktic foraminifera and other zooplankton, the survival of small mixotrophs 4 and phytoplankton 5,6 , and potential for reduced diversity loss in high-latitude settings 7 . Our analysis suggests that impact-driven darkness and body-size-dependent extinction thresholds drove most of the observed extinction patterns. These results suggest that plankton ecologies enhance survival through differences in energy demand and acquisition. Our study bridges the gap between fossil evidence of extinction patterns and the K–Pg impact winter hypothesis, highlighting the value of trait-based models for understanding past biodiversity crises.

Deletion of ARPKD-associated Pkhd1 gene in mice results in decreased Tfap2b expression and eye abnormalities

Abstract Genome-wide association studies report single nucleotide polymorphisms (SNPs) in the PKHD1-TFAP2B genomic interval are associated with primary open-angle glaucoma (POAG) but do not distinguish the causal gene. While neural crest cell (NCC)-specific Tfap2b inactivation causes anterior segment dysgenesis (ASD) and congenital glaucoma (CG), PKHD1 mutations cause autosomal recessive polycystic kidney disease. We now show that Pkhd1 del3-67/del3-67 mice also exhibit CG and ASD. Integrating genetic, epigenetic, bioinformatic and developmental analyses, we show that Pkhd1 del3-67/del3-67 mice lack Tfap2b and AP-2β expression in a subset of periocular mesenchymal cells at E13.5 and its derivatives. Our data suggest the Pkhd1 del3-67 deletion disrupts features of the Pkhd1-Tfap2b genomic architecture essential for Tfap2b cell-specific function. Consistent with this model, Pkhd1 del3-67/+ ;Tfap2b ko/+ mice develop ASD and lack Tfap2b and AP-2β in relevant cell-types. Our results suggest POAG-associated SNPs at this complex locus may impact disease risk by altering TFAP2B regulatory landscapes, providing a mechanistic link and highlighting regulatory complexity of disease-associated regions.

Predicting the ultimate bearing capacity of shallow foundations on ethiopian cohesive soils using a hybrid grey wolf optimizer artificial neural network model

Key role of continental inorganic halogens in the evolution of global air quality

Comparative analysis of intracranial pressure prediction models using optic nerve sheath diameter and additional ultrasound metrics

A fully integrated smart ring for daily biochemical monitoring

Abstract Biochemical analysis complements biophysical measurements by capturing the underlying molecular and metabolic changes that drive physiological health. Here, we introduce a compact, fully integrated smart ring capable of simultaneously monitoring multiple chemical biomarkers in real-time — marking a true biochemical counterpart to existing smart rings. Our ring can continuously measure glucose, ketone, ascorbic acid, uric acid, lactate, and alcohol from passive osmotically extracted sweat, is powered by custom-built high-capacity flexible Zn-AgO batteries, and comprises ultra-compact, energy-efficient electronics for data processing and wireless transmission. It can support ~12 hours of continuous monitoring and preserves personalized calibration stability for ~2 months. The simultaneous biomarker monitoring was validated under diverse daily settings. Reliable, continuous monitoring of glucose and ketone levels showed strong agreement with commercial blood meters and continuous glucose monitors in both healthy and type 1 diabetic individuals, confirming the ring’s accuracy even for at-risk population. Overall, our ring extends beyond commercial smart rings focusing on only biophysical signals, by enabling continuous assessment of biochemical changes and advancing the development of next generation personalized and miniaturized healthcare technologies.

Designing social media to promote productive political dialogue

Absent pleocytosis in infant viral central nervous system infections reflects lymphocyte depletion and cytokine activation

Insights into kinetics, reaction mechanism, thermodynamics, and co-combustion characteristics for Gmelina arborea with polyethylene using thermogravimetric analyzer

Copanlisib in combination with nivolumab formicrosatellite stable colorectal cancer: a phase 1/2 trial

Morphometrics of the skull base for estimating sex among Koreans using 3D CT

Constraining an exoplanet’s magnetic field using star-planet interactions

Theory predicts that a planet with a sufficiently strong magnetic field orbiting close to its host star could induce star-planet magnetic interactions. This is potentially observable as an optical or radio stellar activity signal synchronized with the planet’s orbital period. We analyzed 18 years of high-resolution optical spectroscopy of GJ 436, a low-mass star orbited by a Neptune-sized exoplanet on a polar eccentric orbit. Stellar activity indicators show enhancements at a period corresponding to the exoplanet orbit, modulated by stellar rotation, and the star’s 8-year magnetic cycle. We interpret this as a signal of star-planet magnetic interaction. Using a geometric model, we reproduced these periods if GJ 436 b has a magnetic field strength of 6 to 110 gauss.

A bioorthogonal nanoconcentrisome system for epigenetic and immunometabolic reprogramming of tissue regeneration in aged female rats

Lipid signatures in two functionally selected effluents from clinically relevant postoperative pancreatic fistulas are associated with graded, cell type–specific transcriptional responses

Abstract Clinically relevant postoperative pancreatic fistula (CR-POPF) remains a major cause of morbidity after pancreatoduodenectomy, yet the biochemical composition of postoperative effluents and their effects on anastomotic healing remain poorly understood. We investigated whether CR-POPF effluents exhibit lipolysis-associated lipid signatures and induce defined responses in cellular model systems relevant to anastomotic healing. Drain effluents from 14 patients (7 CR-POPF, 7 non-POPF) underwent GC–MS lipid profiling. Metabolic viability assays (ATP-based readout of cellular stress responses) were performed in peritoneal mesothelial cells and human foreskin fibroblasts as stromal model systems relevant to anastomotic healing, as well as PanC-1 cells. Two CR-POPF effluents associated with reproducible reductions in metabolic viability were functionally selected for transcriptomic profiling. RNA sequencing was performed in mesothelial cells and fibroblasts after exposure to these effluents and monopalmitin. CR-POPF effluents showed coordinated enrichment of long-chain fatty acids and monoacylglycerides. Only a subset reproducibly impaired cellular metabolic viability. Transcriptomic profiling of the two functionally selected CR-POPF effluents revealed a lipid-responsive transcriptional signal across these biologically distinct effluent samples, characterized by induction of ANGPTL4, HMOX1, PLIN2, and PDK4 and consistent with a metabolic and stress-adaptive transcriptional response to lipid exposure. Activation followed a clear gradient (monopalmitin > AES1448 > GR1479) and was more pronounced in mesothelial cells than in fibroblasts. Functionally active CR-POPF effluent samples may carry lipid signals that are associated with a consistent transcriptional signal in peritoneal mesothelial cells and fibroblasts in functionally active effluent samples. The lipid-dependent amplitude and compartment-specific embedding of this signal support a hypothesis-generating framework derived from the two functionally selected CR-POPF effluents.

Epigenetic and 3D genome reprogramming during the aging of the human hippocampus

Changes in gene expression have been observed in the aging human brain, but our understanding of the underlying regulatory mechanisms remains limited. To unravel these complexities, we analyzed single-nucleus gene expression, chromatin accessibility, DNA methylation, and three-dimensional (3D) chromatin architecture from human hippocampal tissues spanning the adult lifespan. We identified both linear and nonlinear dynamic gene regulatory programs during aging. Between the ages of 50 to 75, embryonic yolk sac–derived microglia were depleted and replaced by cells resembling peripheral blood monocyte–derived microglia. Hippocampal astrocytes decreased substantially with age, including those regulating synaptic transmission. Across cell types, 3D genome architecture underwent global erosion. Our analysis provides insights for how altered gene regulatory programs promote cell type–specific aging phenotypes in the human brain.

IDBac: an open-access web platform to identify bacteria and analyze relationships in culture collections using MALDI-TOF mass spectrometry

Abstract The identification and analysis of bacteria is central to the microbiological sciences. While gene sequencing methods have been the standard to achieve this, use of MALDI-TOF mass spectrometry (MS), particularly in clinical microbiology, can provide high-throughput identification to the subspecies level. However, biotyping has yet to be adopted outside of clinical settings due to the lack of a centralized public database of MS protein signatures that would facilitate isolate identification via spectral comparison. Further, most current MALDI MS data analysis platforms lack meaningful ways to compare properties from large numbers of bacterial isolates. Herein we present the IDBac web platform, a crowd-sourced central knowledgebase of protein MS signatures spanning seven bacterial phyla. Accompanying the knowledgebase is analysis infrastructure to identify unknown isolates, probe relationships within culture collections using metadata integration, and visualize specialized metabolite differences within groups of closely related bacteria. To highlight this utility and encourage wide community contribution, examples of each are presented.

Age-specific allometric modelling and ecosystem carbon stock of Phyllostachys reticulata (Rupr.) K.Koch in Ziro Valley, Arunachal Pradesh, India

Step geometry–guided growth of rhombohedral graphene

Rhombohedral (ABC)–stacked graphene has emerged as a platform for exploring correlated and topological physics. However, its large-scale, pure-phase synthesis has been hindered by intrinsic thermodynamic metastability and kinetic instability. In this work, we introduce a step geometry–guided epitaxial strategy to deterministically control interlayer slip, enabling the synthesis of pure-phase rhombohedral graphene. Using this approach, we obtained pure (phase purity > 99%) rhombohedral graphene with an area reaching 160 micrometers by 80 micrometers and thickness ranging from ~15 layers to ~120 nanometers. The resulting samples establish the first comprehensive reference dataset of Raman fingerprints and intrinsic band structures from few-layer films to ~200-layer bulk. Electronic transport measurements reveal a layer-antiferromagnetic state and the quantum anomalous Hall effect, enabling scalable exploration of next-generation quantum science and technology applications.

Bioinspired porous metal-amino acid nanozymes enable multi-pathway treatment of atherosclerosis through anti-oxidation and pro-efferocytosis

Numerical investigation of liquid-Cooled battery thermal management system configurations for a lithium-ion battery pack with experimental validation

Abstract Efficient thermal management is crucial for lithium-ion battery safety and longevity in Electric Vehicles (EVs). This study presents a numerical investigation and experimental validation of liquid cooling strategies for NMC lithium-ion battery modules, comparing serpentine (Configuration 1), parallel (Configuration 2), and parallel/counter-flow hybrid (Configuration 3) layouts. A custom-built 4-cell test rig validated against CFD simulations showed close agreement, with relative deviations below 0.6%, confirming model reliability. Under regulated flow conditions, clear differences in thermal and hydraulic behavior were observed. Configuration 1 exhibited the highest thermal stress, with peak temperatures reaching 75.7 $$\:^\circ\:C$$ (cell 7) and 74.1 $$\:\:^\circ\:C$$ (cell 18) due to downstream heat accumulation and limited contact area, alongside the largest temperature difference (ΔT = 11.0 K) and highest pressure drop (27.3 Pa). Configuration 2 reduced peak pack temperature to 70.6 $$\:^\circ\:C$$ at cell 18 (6.7% lower vs. Configuration 1) and 64.7 $$\:^\circ\:C$$ at cell 7 (14.8% lower), achieving the best intra-cell uniformity (σ = 0.47 K, CV = 5.6%) and lowest pressure drop (9.1 Pa). Configuration 3 offered the most balanced cooling, lowering maximum cell temperature by 7.6% compared to Configuration 1 and 0.9% compared to Configuration 2, while the maximum temperature of cell 18 decreased by 11.8%. It achieved the narrowest inter-cell ΔT (4.1 K), a 62.5% and 11% reduction versus Configurations 1 and 2, respectively, with the lowest σ = 1.0 K (CV = 0.32%). Overall, serpentine cooling is simple but thermally inefficient, parallel flow is the most energy-efficient, and the hybrid parallel/counter-flow design delivers the best overall thermal balance while lowering the required pumping power by about 89%, making it the most suitable layout for safe and reliable EV battery operation.