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Anthropogenic accessibility and observer inequality dictate spatial biodiversity patterns in Malaysia

Spin-state engineering of cobalt(IV)-oxo enables direct oxygen atom transfer for high-efficiency olefin epoxidation

High-valent metal-oxo species, such as cobalt(IV)-oxo (Co IV =O) complexes, represent promising candidates for catalytic olefin epoxidation via oxygen atom transfer (OAT) under mild conditions. However, their utility is often limited by radical-mediated side reactions stemming from stepwise electron-transfer mechanisms. Here, we report a strategy to circumvent this limitation by modulating the spin state of the Co IV =O center through geometry-mediated ligand-field adjustment. Specifically, we employ a planar tricoordinated cobalt site to activate peroxymonosulfate (PMS), generating an intermediate-spin Co IV =O species ((O 3 )Co IV =O, S = 3/2). Unlike its planar tetra-coordinated low-spin counterpart ((O 4 )Co IV =O, S = 1/2), the weakened equatorial coordination field in this configuration reduces the crystal-field splitting energy and rearranges orbital energy levels, stabilizing the empty σ* (d z 2 -p z ) orbital at a lower energy level, enabling direct transfer of a π-electron pair from the olefin substrate. Consequently, the OAT mechanism shifts from a stepwise single-electron transfer to a concerted two-electron pathway, bypassing radical intermediate formation and enhancing both reactivity and selectivity. In the epoxidation of trans-stilbene and derivatives, the (O 3 )Co IV =O catalyst achieves up to 89.2% conversion with 99.9% selectivity, substantially outperforming conventional noble-metal-based systems. Our findings underscore the critical role of spin-state control in promoting concerted OAT and open avenues for designing next-generation oxidation catalysts.

Prediction of pre- and postfusion conformations of class I fusion proteins with AlphaFold2

Viruses such as coronaviruses or filoviruses use their surface glycoproteins (GPs) to attach to the host cell, triggering the fusion of the viral membrane with the endosome membrane. Epitopes on the viral GP are major targets for antibody-mediated recognition and neutralization. During the fusion process, the GP undergoes conformational changes triggered by fluctuations in environmental pH. Structural states are typically classified into three distinct conformations: prefusion, intermediate, and postfusion. These conformations serve as essential templates for prediction of conformational epitopes and structure-based vaccine design. Despite their importance, many viral GP structures remain absent from the Protein Data Bank (PDB). Fortunately, recent breakthroughs in computational structure prediction have greatly enhanced the accuracy and accessibility of protein modeling. In this study, we utilized AlphaFold2-Multimer (AF2-M), version 2.3, to predict various GP structural conformations and observed that the overall frequency of predictions in the postfusion conformation is low. Therefore, we hypothesized that adapting the AF2-M protocol is necessary to enrich for specific conformations, thereby enabling the prediction of both pre- and postfusion conformations. AF2-M requires only the input sequence and internally generates multiple sequence alignments (MSAs) and optional templates before applying its pretrained model weights. We tested the use of template data to enrich pre- or postfusion conformations and demonstrated that our approach significantly increases the prediction frequency of class I fusion protein structures in both conformations, with the template dataset playing a crucial role in guiding modeling towards the intended state. Furthermore, we showed that the lack of correlation between pLDDT and TM-scores suggests that low pLDDT values may obscure the presence of valid alternative conformations.

A novel eco-friendly HPTLC approach for the simultaneous determination of erdosteine, ibuprofen and pseudoephedrine pharmaceutical combination

Abstract This paper introduces the first validated and ecofriendly high-performance thin-layer chromatographic (HPTLC) method for the simultaneous determination of erdosteine (ERD), ibuprofen (IBU), and pseudoephedrine (PSE) pharmaceutical combination. This drug combination aids in treating symptoms associated with upper respiratory tract infections (URTIs) by providing mucolytic, analgesic, anti-inflammatory, and decongestant effects within a single therapeutic regimen. The chromatographic separation was effectively achieved on a silica gel 60F 254 plate using a mobile phase composed of ethyl acetate: methanol: ammonia (7:1.4:0.5, v/v), and UV detection at 210 nm. The analytes were well resolved with retardation factors (R f ) of 0.06, 0.23, and 0.35 for ERD, IBU, and PSE, respectively. The method demonstrated high accuracy, with recoveries ranging from 98.4% to 101.2% and excellent precision, as indicated by % RSD values below 2%. It also showed high sensitivity, with detection limits of 0.014 µg/spot, 0.002 µg/spot and 0.150 µg/spot for ERD, IBU, and PSE, respectively. The method’s environmental sustainability was confirmed using the Analytical EcoScale, Analytical GREEnness (AGREE) calculator and Green Analytical Procedure Index (GAPI). Additionally, its overall whiteness profile was assessed using the Red-Green-Blue (RGB12) model approach, highlighting its analytical efficiency and eco-friendly design.

A GTP synthase ribozyme with increased GTP turnover

Before the invention of encoded protein translation, early stages of life likely relied on catalytic RNAs (ribozymes). To test how such a system could have functioned, researchers have developed ribozymes that could have provided central functions. The central function of self-replication would have required templated RNA polymerization of nucleotides, which is energetically driven in today’s life forms by the use of nucleoside 5′-triphosphates (NTPs). We previously showed that ribozymes can catalyze the formation of guanosine 5′-triphosphate (GTP) from guanosine and the prebiotically plausible polyphosphorylation reagent cyclic trimetaphosphate (cTmp) by generating a guanosine triphosphorylation ribozyme (GTR) using an in vitro selection in emulsion. This ribozyme (GTR1) had a catalytic rate enhancement of about 18,000-fold but a turnover of only about 1.7. Here, we improved this ribozyme by emulsion selection from a doped library of GTR1 that was metabolically coupled to a polymerase ribozyme. High-throughput sequencing and biochemical analysis identified the most efficient variant of GTR1 with 19 mutations, which increased the GTP turnover number to ~13. Biochemical analysis of this GTR1e revealed biphasic reaction kinetics with an apparent overall K M APP around 11 mM for cTmp. When coupled to an RNA polymerase ribozyme, up to five guanosines were incorporated into an RNA polymer, which represents an important step toward modeling an RNA-based life form in the lab.

Persistent symptoms, cognitive impairment, and clinical predictors of long COVID one year after Omicron infection: A clinical case–control study from the Faroe Islands

Background Six years since the emergence of SARS-CoV-2, the newer variants of the virus continue to have long-term health effects. Objectives The aim of the study was to investigate persistent symptoms, cognitive impairment, and clinical and paraclinical predictors of long COVID in individuals infected during the Omicron wave. Methods We conducted a clinical case-control study including participants with persistent symptoms up to 13 months after confirmed SARS-CoV-2 Omicron infection (long COVID or LC group) and antibody-verified never-infected controls (NI group). Results A total symptom score based on a 24-item questionnaire was strongly associated with increased odds of long COVID (adjusted odds ratio (aOR) 1.21, 95% CI 1.13–1.30, p < 0.001). Sub-analysis showed particularly strong associations for fatigue, cognitive impairment, neurological symptoms, and symptoms from the cardiopulmonary and musculoskeletal systems. Both mental impairment and fatigue independently predicted long COVID (aOR 1.27, 95% CI 1.14–1.42, p < 0.001, and aOR 1.27, 95% CI 1.11–1.46, p < 0.001, respectively). Additionally, a higher number of self-reported infections during the follow-up period increased the odds of long COVID (aOR 1.57, 95% CI 1.06–2.34, p = 0.025), though this was not reflected in antibiotic use. Finally, blood analyzes showed that lower white blood cell counts were associated with increased odds of long COVID in women, but not in men, however the clinical significance of this finding remains uncertain. Conclusions One year after Omicron infection, a subset of people continue to experience a substantial symptom burden, particularly fatigue, cognitive impairment, and mental well-being, and a higher frequency of intercurrent infections.

Author Correction: Performance enhancement of electrochemical discharge micromachining of borosilicate glass using nitrogen gas assistance

Reply to González González et al.: The contribution of bacteria to kidney stone formation

A fusion-deletion genomic-event underlies poor prognosis in young patients with luminal breast cancer

Breast cancer in young patients, particularly those with the luminal subtype, exhibits more aggressive behavior and poorer clinical outcomes compared with older patients. However, the genomic mechanisms underlying this age-associated aggressiveness remains poorly understood. In this study, we integrated multi-omics data, including gene fusions, mutations, and copy number variations, to investigate age-related molecular heterogeneity in breast cancer. We identified the co-occurrence of the EEF1AKNMT::DNM3 ( ED ) fusion and KDM6B deletion as a novel prognostic biomarker associated with aggressive tumor biology and reduced survival in luminal breast cancer. Moreover, we discovered a widespread pattern of genomic remodeling in early-onset disease, characterized by an increased fusion burden, distinct mutational profiles, and dysregulated transcriptional programs that collectively contribute to high-risk clinical phenotypes. These findings provide mechanistic insights into the enhanced aggressiveness of breast cancer in young patients and identify potential biomarkers for improved risk stratification.

Application of solid modeling techniques for geometric simulation of surface topography in boring operations

Dual enhancement of superconductivity in FeSe/SrTiO ₃ via orbital and correlation synergy

In iron-based superconductors, the d z 2 orbital band typically resides far below the Fermi level and has not been considered to participate in Cooper pairing. Here, using monolayer FeSe/SrTiO 3 as a model system, we demonstrate that tip-induced tensile strain controllably shifts the d z 2 band toward the Fermi level, driving a two-stage enhancement of superconductivity. In-plane lattice expansion first enhances electronic correlation, amplifying superconductivity in the initial stage. As strain further increases, the upward-shifted d z 2 band hybridizes with the d xy band, reconstructing the pairing-active d -orbital bands and inducing a secondary, stronger gap enhancement. Collectively, these two stages enlarge the superconducting gap from 17.8 to 23.6 meV. Throughout this process, invariant Fermi wave vectors confirm that the enhancement originates from band renormalization and reconstruction rather than carrier doping. Our work establishes a route to tailor superconducting states via strain-activated electronic correlations and band engineering, and reveals a previously unrecognized orbital-selective pairing mechanism with broad implications for correlated multiband superconductors.

PianoGym: Safe post-action piano rhythm training with fatigue constraints

Bimanual piano rhythm training must maintain precise interlimb timing under limited practice time and under fatigue constraints, while feedback on performance is typically available only after an exercise. A piano practice gym environment (PianoGym) is used as a reproducible simulator for fatigue-constrained piano rhythm training under post-action feedback. The training task is formulated as a fatigue-constrained, post-action, partially observable Markov decision process (POMDP). In this POMDP, a controller observes beat asynchrony, dominance gap, synchronization fidelity, and two fatigue signals, and selects the next exercise from a finite library of structured practice actions. To handle delayed measurements and fatigue feasibility under the simulator budget, we introduce a dual-timescale safety layer. The slow Lagrangian part tracks a long-horizon average constraint using revealed true fatigue, while the fast predictive guard screens candidate actions using the online fatigue estimate. On top of this layer, a piano model predictive controller (PianoMPC) uses certainty-equivalent planning and performs finite-horizon rollouts over a calibrated surrogate environment model and searches only within guard-filtered action sets. In the main three-profile experiment, PianoMPC achieves mean time-to-mastery values of 24.4 to 28.2 steps and FeasibleRate values of 0.90 to 0.95 under the shared environment-side guard. Under the same environment-side guard, it also outperforms bandit and value-based agents. These results indicate that model-predictive planning can convert a fixed operational fatigue budget into faster progress in fatigue-aware piano practice within the PianoGym simulator and its stated surrogate fatigue and skill-dynamics assumptions.

Tomato-derived carbon quantum dots: composition-driven structure and copper sensing potential

Abstract Carbon quantum dots (CQDs) were synthesized via a green, bottom-up approach from tomato biomass, using stems and fruits as distinct carbon precursors. To tailor their surface chemistry and optical response, m-aminobenzoic acid was used as a nitrogen-containing dopant during synthesis. The resulting CQDs form colloidally stable, nanoscale aggregates in aqueous media and exhibit strong excitation-dependent photoluminescence, with maximum emission under excitation at 300 and 370 nm. Comprehensive structural and surface analyses reveal that precursor origin significantly influences defect density, hybridization states, and functional group distribution, directly governing luminescent behavior. Both fruit-derived and stem-derived CQDs display efficient fluorescence quenching upon coordination with Cu²⁺ ions, enabling sensitive detection with limits of detection of 0.059 µM and 0.048 µM, respectively. The enhanced sensing performance is attributed to surface-accessible oxygen- and nitrogen-containing functional groups that promote strong metal–ligand interactions. This work demonstrates a sustainable and low-cost strategy for converting agricultural waste into functional nanomaterials, while highlighting the critical role of biomass composition and surface chemistry in tuning CQD photophysics and metal-ion sensing capabilities.

Integrating trophic importance into conservation of terrestrial vertebrates

There is global consensus on the need to prioritize conservation efforts to prevent biodiversity loss and defaunation. Most current conservation initiatives focus on areas with high species diversity or many threatened species, treating species independently and neglecting trophic interactions. To address these oversights, we developed a framework to quantify species’ roles along continuums of trophic importance (TI) and global endangerment (GE), estimated from a global terrestrial meta-food web of over 25,000 vertebrate species. We combined TI with IUCN Red List categories to create a Trophic Importance Global Endangerment (TIGE) index, integrating TI and extinction risk. Our analysis revealed that the TI index provides distinct and complementary insights beyond species endangerment. Systematic conservation planning indicated that prioritizing areas based on TIGE shows significant spatial inconsistency compared to traditional taxonomic approaches. Our findings emphasize the value of incorporating species trophic network importance into conservation strategies to reconcile species ecosystem functioning and biodiversity conservation.

Combined effect of metabolic syndrome and cancer on depression

Background Cancer survivors frequently experience depression and metabolic dysfunction; however, the combined impact of these conditions remains understudied. Aim This study aimed to examine the joint associations between cancer, metabolic syndrome, and depression. Methods Data from the 2007–2021 Korea National Health and Nutrition Examination Survey encompassed 57,176 participants aged ≥ 19 years. Cancer diagnosis and components of metabolic syndrome (waist circumference, triglycerides, high-density lipoprotein cholesterol, blood pressure, and fasting glucose) were obtained through self-report or clinical measurement. Depression was assessed using a single-item question regarding persistent sadness or hopelessness. Multivariable logistic regression models evaluated the associations among cancer, metabolic syndrome, and depression, adjusting for sociodemographic and lifestyle factors. Results Among participants, 1,691 (3.0%) had cancer, 17,510 (30.7%) met criteria for metabolic syndrome, and 7,472 (13.1%) reported depression. Cancer was independently associated with increased risk of depression (odds ratio: 1.26; 95% confidence interval: 1.10–1.45). While metabolic syndrome alone was not significantly associated with depression, patients with cancer who had elevated triglycerides (≥ 150 mg/dL) or decreased high-density lipoprotein cholesterol exhibited substantially higher risk of depression (odds ratio: 1.51; 95% confidence interval: 1.17–1.95 and odds ratio: 1.32; 95% confidence interval: 1.07–1.62, respectively). The association between elevated triglycerides in cancer survivors and depression remained robust after FDR correction. Conclusions Specific lipid abnormalities, rather than metabolic syndrome as a whole, were significantly associated with a higher prevalence of depression among cancer survivors. These findings underscore the need for integrated screening and management that address both metabolic dysfunction and mental health in cancer survivorship care.

A circular economy framework to mitigate water scarcity and river pollution in Delhi, India

The <i>Campylobacter jejuni</i> flagellar V-ring discerns viscosity levels to alter swimming velocity, metabolic gene expression, and fitness

Campylobacter jejuni is an intestinal commensal of birds and animals and a leading cause of bacterial diarrheal disease in humans. In hosts, C. jejuni primarily resides in the mucus layer atop the lower intestinal epithelium. Persistence in this niche requires a single flagellar motor at both C. jejuni poles that generates high torque for flagellar rotation to facilitate motility and high swimming velocities. Unlike many bacterial flagellates, C. jejuni swimming velocity increases as external viscosity increases. We identified a complex formed by FlgV, VidA, and VidC (Cjj81176_1732) positioned near the MS-ring-rotor junction in the flagellar motor we annotated as the V-ring. Viscosity-influenced growth, modulation of swimming velocity, and transcription of iron/heme acquisition, respiratory, and energy-generating systems were dependent on the V-ring. C. jejuni Δ flgV and Δ vidC populations lacking a complete V-ring were motile, but could not optimally modulate swimming velocity. Like nonmotile flagellar stator or filament mutants, motile V-ring mutants had in vivo and in vitro growth and viability defects and dysregulated transcription of genes likely impacting physiology. Because the V-ring mutants behaved similarly as nonmotile mutants that experience little to no viscous drag on the filament, we propose C. jejuni V-ring mutants cannot detect viscous drag on their rotating filaments. We propose the V-ring evolved in C. jejuni and potentially other bacteria producing high torque flagellar motors to monitor external viscosity information via viscous drag on the rotating flagellar filament to adjust swimming velocity, transcription, and physiology for optimal fitness in different host lower intestinal niches.

Designing the syllabus for the EAP course “Architectural Art English”: A needs and genre analysis-based approach

This paper details the design and development of a discipline-specific English for Academic Purposes (EAP) syllabus for undergraduate students majoring in architecture and design related disciplines in an art school in China. Guided by the comprehensive needs analysis model established by Dudley-Evans and St. John [Developments in English for specific purposes: a multi-disciplinary approach. Cambridge University Press (1998)] and Swales [Genre analysis: English in academic and research settings. Cambridge University Press (1990)] genre theory, this study employed a university-wide questionnaire to gather data from 650 participants, including students and faculty. The needs analysis identified a critical disparity between students’ target academic aspirations—such as engaging in international collaboration, pursuing studies abroad, and understanding foreign lectures—and their present situational capabilities, particularly in listening comprehension and command of disciplinary vocabulary. In response to these findings, the proposed “Architectural Art English” syllabus is constructed around a genre-based, content and language integrated learning (CLIL) as well as task-based language teaching (TBLT) approach. It systematically incorporates seven key academic and professional genres relevant to the field: textbooks and monographs, research papers, case studies, and lecture scripts as input genres; and design statements, presentation scripts, and research abstracts as output genres. Each instructional unit is organized around a central architectural theme, utilizing authentic cases and genre analysis of move structures to make disciplinary discourse conventions explicit. The pedagogical framework emphasizes task-based learning, featuring authentic activities such as case analysis, design project presentations, and paper abstract writing to bridge the gap between language skills and disciplinary knowledge. This syllabus aims to addresses the complex interaction of learners’ target needs, subjective wants, and current proficiencies, facilitating their active participation in the global academic community of architecture and design.

Moderate electrical muscle stimulation during voluntary movement does not disrupt the sense of agency or ownership

Consecutive catalytic steps of viral RNA polymerase and exonuclease suggest a way to overcome intrinsic nucleotide analogue resistance

Nucleotide analogues (NAs) have been successfully used for the treatment of various RNA virus infections by selectively targeting the viral RNA-dependent RNA polymerase (RdRp) for incorporation into the viral genome. However two major families of human-infecting RNA viruses, Coronaviridae (CoV) and Arenaviridae, encode exonuclease domains that may recognize and remove incorporated NAs, thus providing natural resistance against some of these drugs. Both polymerization and excision reactions are mechanistically centered on the nucleotide α-phosphate, enabling the potential for sequential inhibition of both RNA synthesis and repair. Here, we provide structural evidence of inversion of configuration at the phosphorus center during polymerization, demonstrating that the SARS-CoV-2 RdRp proceeds through an S N 2 mechanism. A 2.39 Å resolution cryo-EM structure of a ternary replication complex bound to RNA and an α-thio–modified NTP shows that incorporation of the preferred S P isomer at the 3′ end of the RNA yields a phosphorothioate linkage in the R P configuration. This R P -phosphorothioate RNA product shows reduced cleavage by both the SARS-CoV-2 and three arenavirus RNA exonucleases, revealing a stereochemical preference opposite to that of structurally related DNA exonucleases. This observation contradicts the prevailing assumption that sulfur substitution at the metal-coordinating oxygen universally blocks catalysis. Instead, RNA exonuclease stereoselectivity appears to be shaped not only by metal–sulfur interactions but also by the geometry of nucleophile activation. These findings provide mechanistic insights into phosphoryl transfer in viral polymerases and exonucleases and highlight opportunities to counteract intrinsic nuclease-mediated resistance against antiviral nucleotide analogues.