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Standard polymer biodegradability tests in industrial compost rely on running incubations at high initial polymer concentrations and exclusively determining polymer mineralization to carbon dioxide, while not analyzing the nonmineralized fraction of polymer-added carbon. This work presents an approach that combines the use of 13C-labeled polyesters in compost incubations to selectively track both mineralized and nonmineralized polyester 13C at low initial polyester concentrations with analysis of residual polyester during the incubations by compost solvent extraction coupled to proton nuclear magnetic resonance spectroscopy. Incubations with 13C-labeled poly(butylene adipate-co-terephthalate) (PBAT) and poly(butylene sebacate-co-terephthalate) (PBSeT) at low initial concentrations exhibited shorter initial lag-phases and higher relative rates of mineralization as compared to parallel standard incubations run at high initial concentrations of nonlabeled PBAT and PBSeT, suggesting that the latter used polyester amounts in excess of the metabolic capacity of the compost microbial community. Mass balance assessment on polyester-added 13C over the incubations confirmed accurate 13C tracking in both mineralized and nonmineralized pools, despite low initial polyester concentrations. Extraction of residual 13C-labeled and nonlabeled polyesters revealed substantial incorporation of polyester carbon into microbial biomass during compost incubations. Biodegradability tests that exclusively rely on mineralization measurements may therefore underestimate polymer biodegradation in compost.

Ustiloxins are toxic cyclic peptides produced by the rice false smut fungus Ustilaginoidea virens. False smut disease turns rice grains into yellow-orange spores later turned into greenish-black smut balls, significantly reducing yield and grain quality. Due to their hydrophilic nature ustiloxins leach from spore balls and contaminate paddy soil, water, and rice products. They block eukaryotic cell division by binding tubulin and inhibit microtubule polymerization. This review provides information on advances in ustiloxin biology and control. It summarizes ribosomally synthesized and post-translationally modified peptides (RiPPs) biosynthesis and recent insights into pathway genes, regulatory networks including target of rapamycin (TOR) signaling, and comparative fungal genomics. Environmental occurrence is reviewed with emphasis on persistence in soil, water and translocation into rice grains. Ecotoxicological evidence is consolidated, spanning phytotoxicity, effects on beneficial microbes, aquatic organisms, and mammalian toxicity supported by in vivo and mechanistic studies. Progress in detection is outlined with improved LC-MS/MS, immunoassays, and emerging biosensors for field diagnostics. Management strategies are evaluated, including resistant cultivars, disease forecasting, fungicidal and biological controls, and post-harvest detoxification via enzymatic and physical approaches. A dedicated risk assessment discusses human dietary exposure, regulatory status, and the need for maximum limits. The review concludes by highlighting research priorities such as multi-omics, spread modeling, and biotechnological interventions, to close key knowledge gaps and enable effective monitoring and mitigation toward an ustiloxin-free rice agroecosystem.

Wearable biochemical sensors offer a promising route to noninvasive cortisol analysis. However, existing sweat-cortisol sensing platforms often rely on complex collection devices, electronic readout modules, or dedicated instrumentation. Here, we report a multilayer wood-derived hydrogel patch for portable optical analysis of sweat cortisol. The patch integrates the anisotropic porous framework of delignified balsa wood with a polyacrylamide/poly(vinyl alcohol)/glycerol (PAAm/PVA/glycerol) hydrogel network to form a flexible, hydrophilic sensing layer for pump-free sweat uptake. A cortisol-responsive Förster resonance energy transfer (FRET) probe embedded in the sensing layer enables molecular recognition, while adhesive and encapsulation layers improve wet-skin attachment and water retention. A companion smartphone application provides portable cortisol quantification. Under the tested conditions, the complete patch produced a distinguishable response at the lowest experimentally evaluated concentration of 1 pM in human sweat matrices. Pilot human studies supported the feasibility of interval sweat cortisol analysis during exercise-associated, time-of-day-related, and repeated-measurement scenarios. This work extends wood-derived materials into wearable biosensing and provides a bio-derived integration strategy for portable biochemical analysis.

The electrochemical conversion of nitrite/nitrate (NOx -) to ammonia (NH3) offers a sustainable route for NH3 production, particularly coupled with efficient air plasma. However, balancing catalyst activity/stability for gram-level NH3 production remains major challenges. In this study, we report a low-crystallinity phosphorus-doped cobalt electrode (P─Co/NF) for efficient and stable NH3 synthesis via NO2 - reduction, achieving an impressive NH3 yield rate of 414.51 mg h-1 cm-2 and outstanding long-term stability of 1000 h. Comprehensive characterizations and theoretical calculations reveal that the dynamically evolved P─Co/Co(OH)2 heterostructure with asymmetric P─Co─O/OH active sites simultaneously optimizes NO2 - activation and water dissociation. The synergistic interplay between P─Co and Co(OH)2 layer facilitates sufficient *H supply and moderate intermediate adsorption, thereby suppressing H2 evolution. To enable direct air-to-NH3 conversion, a complete system is established by integrating electrocatalysis with microwave plasma and intermittent solar power, achieving an average NH3 yield of 1.19 g per day with Faradaic efficiency >90%. When scaled up to a 100 cm2 flow cell, the system delivers an NH3 production rate of 4.97 g h-1. This work provides a paradigm for designing dynamic asymmetric sites that overcome activity-stability tradeoff under industrial-level current density, paving the way toward the decentralized and sustainable NH3 production.

Understanding the aqueous chemistry of cations in solution is central to modeling ion transport, complexation, and reactivity. Calcium, for example, plays a critical role in biological and environmental systems; however, a fundamental understanding of its coordination in dilute, aqueous solution is lacking. There is still debate regarding the number of water molecules in its first solvation shell. Moreover, studies of Ca2+ coordination in aqueous complexes with ligands other than water are rare. Herein, we apply Ca K-edge x-ray absorption near-edge structure (XANES) and extended x-ray absorption fine structure (EXAFS) spectroscopy combined with ab initio molecular dynamics and time-dependent density functional theory to investigate the coordination environment of aqueous Ca2+. On the one hand, EXAFS spectroscopy is sensitive to bond distances; however, the determination of coordination numbers can be imprecise. XANES spectroscopy, on the other hand, is sensitive to molecular symmetry and therefore to coordination number. We first confirmed that calcium is coordinated, on average, by seven water molecules in dilute aqueous solution. We then extended this approach to examine the coordination environment of aqueous Ca2+ ethylenediaminetetraacetic acid (EDTA) complexes. Notably, a water molecule was present in the first coordination shell of Ca2+, in addition to four O atoms and two N atoms from EDTA4-, such that Ca2+ achieved sevenfold coordination. We conclude that Ca2+ tends to adopt low-symmetry, 7-coordinate complexes in aqueous solution, even in the presence of a hexadentate chelator. Our work lays the groundwork needed to understand Ca coordination in numerous biological and environmental systems.

We describe a chromosome-level, pseudo-haplotype-resolved genome assembly from a female bluethroat (Luscinia s. svecica). The assembly comprises two pseudo-haplotypes of 1461 Mb and 1171 Mb, with 77.4% and 88.4% scaffolded into 40 autosomal chromosomes and the W and Z sex chromosomes in pseudo-haplotype one. Assembly completeness is high (BUSCO 99.2% and 94.9%), with 22,462 and 18,769 annotated protein-coding genes for pseudo-haplotypes one and two, respectively. The use of Oxford Nanopore Technologies sequencing enables resolution of genomic regions that are often fragmented in genome assemblies, including the hypervariable Major Histocompatibility Complex (MHC). We find that MHC loci include both the canonical organization of tandemly duplicated MHCIIβ genes with a single MHCIIα, and a distinct arrangement in which MHCI and MHCIIβ loci are interspersed. Substantial structural differences between the two assembled chromosome 35 homologs are resolved across the MHC region.

The combined preservation of soft tissues, biomineralized structures, and molecular biomarkers is rare; yet, such finds offer key insights into ancient physiology, ecology, and taphonomy. We integrate organic geochemical analyses with high-resolution micro-mineral imaging of a three-dimensionally preserved Cretaceous pterosaur wing phalanx from Brazil to reveal steroid biomarkers and multi-stage mineralization pathways underlying its preservation. A localized redox shift toward acidic, oxidative conditions around the carcass played a central role. Microbial decay generated acidity that promoted early phosphate mineralization (fluorapatite), stabilizing tissues. This fluorapatite is associated with barite and celestite indicating a microenvironment with enhanced microbial sulfate production. Following phosphatization, three phases of carbonate mineralization encapsulated organic compounds, protecting them from diagenetic alteration. Molecular analyses report steroids in pterosaurs, with δ13C values indicating a fish- and cephalopod-based diet, highlighting early mineralization as key to long-term biomolecule preservation.

At the intersection of ecological, psychoacoustic, and anthropological perspectives, this study examines how listeners living in Senegal's Sahelian region perceive seasonal and diurnal patterns in local soundscapes. Field recordings representing rainy and dry seasons, as well as different times of day, were first characterized using ecoacoustic analyses that revealed differences in spectro-temporal modulations. The recordings were then presented to two groups: Senegalese pastoralists (Peul herders) living in the Ferlo (n = 9) and a French control group with no prior exposure to the region (n = 31). Participants completed an identification task for season and time of day. The Senegalese group also took part in a semi-guided anthropological interview. Both groups failed to assign the correct labels. Individual performances were correlated across tasks, suggesting stable perceptual abilities. Stimulus-level analyses revealed shared perceptual structure for time of day, but not for season. Semi-guided interviews revealed that the Senegalese participants based their responses on biophonic information. This pilot study suggests that soundscape perception of seasonal and temporal variations relies on both shared invariants and culturally mediated variants. It also highlights the value of combining psychoacoustics, anthropology, and ecology to better understand soundscape perception.

Urban lakes play a vital role in flood disaster mitigation and water-climate maintenance. However, excessive phosphorus inputs resulting from urban development constitute a significant factor in the deterioration of ecosystems. In this study, samples of sediment profiles from three representative urban lakes (Xianghu Lake, Qianhu Lake, and Aixihu Lake) in Nanchang were collected to investigate the sources and the pollution condition of phosphorus. Results indicated that sediments in Qianhu Lake exhibited the highest concentration of total phosphorus (923.06-1630.17 mg/kg), while Xianghu Lake exhibited the lowest levels. Calcium-bound phosphorus (Ca-P) dominated in all three lakes (accounting for over 30% of total phosphorus), followed by iron-bound phosphorus (Fe-P) and detrital phosphorus (De-P). While the organic phosphorus (Org-P) and exchangeable phosphorus (Ex-P) constituted the lowest proportions. In all the lakes, clay dominated the sediment composition (≥ 34%), followed by coarse silt, while fine silt was the least abundant. Correlation analysis revealed that grain size and organic matter constrained the concentrations of phosphorus speciation. The Absolute Principal Component Score-Multiple Linear Regression model (APCS-MLR) revealed that phosphorus pollution in Xianghu Lake, Qianhu Lake, and Aixihu Lake was predominantly driven by agricultural non-point sources, with the contributions of more than 35%, followed by industrial emissions and domestic sewage, which corresponded with the extensive agricultural land around the lake. Nemerow integrated pollution index analysis revealed that all the lakes were heavily polluted, with the F values of the three lakes more than 1.90. Consequently, comprehensive management measures, including optimizing agricultural fertilization-irrigation forms and restricting pollutant discharges, are required to prevent further deterioration. This study is of practical significance for the prevention of lake eutrophication. It provides a scientific basis for biogeochemical cycles and the protection and management of aquatic ecosystems in the urban lakes.

Geographic knowledge graph (GeoKG) organizes the geographical entities and their relationships, which provides rich spatial semantic to serve various geographic artificial intelligence tasks by knowledge graph representation learning (KGRL). As a bridge between the knowledge graph and downstream tasks, KGRL results in a speedup of inference by embedding the entities and relationships of KG into a low-dimensional vector space. However, the existing KGRLs treated subgraphs in different regions uniformly, ignoring the spatial heterogeneity of GeoKG. It may result in significant performance differences across regions. To address this problem, this study proposes a region adaptive KGRL (RA-KGRL) method to mitigate the impact of spatial heterogeneity on performance. Specifically, RA-KGRL first splits the original GeoKG into subgraphs by introducing regional priors. Then, RA-KGRL learns local models for the subgraphs and performs local-to-global optimization to learn accurate global model. Extensive experiments on thirteen datasets indicate that RA-KGRL is comparable or even better than baselines on the traditional metrics, and outperforms all baselines on the new region adaptive metrics. This study provides a methodological reference for improving the performance of KGRLs on spatial heterogeneity scenarios.

We report 804 metagenome-assembled genomes (MAGs) reconstructed from a water conditioning tank during the establishment of an artificial seawater aquarium at SEA LIFE Nagoya. These MAGs were assigned to 27 phyla (26 bacterial phyla and 1 archaeal phylum), providing a genome-resolved resource for investigating the microbial diversity of artificially managed marine environments.

Coral reefs rely on minimum thresholds of live hard coral cover to sustain key ecological and geomorphic functions, including habitat provisioning, carbonate production, and wave attenuation. While declining hard coral cover is widely recognised as a driver of reef degradation, the boundaries at which reefs transition between distinct functional states remain poorly defined-particularly across reefs with contrasting baseline conditions, where absolute cover values are not directly comparable. To address this gap, we quantified long-term changes in benthic composition from 1995 to 2022 across three eco-geomorphologically distinct reefs spanning the northern, central, and southern Great Barrier Reef. Hard coral cover was indexed relative to each reef's historical maximum, allowing reef state transitions to be parameterised using comparable thresholds. Three reef states were identified, driven predominantly by shifts in coral cover and corresponding changes in algal dominance, with secondary reef-specific reorganisation in coral morphological composition shaped by baseline community structure. 'Healthy' states were characterised by high structural complexity; 'coping' states by overall hard coral cover decline, with reef-specific shifts in dominant coral morphology; and 'struggling' states by near-complete coral loss and algal dominance. Indexed hard coral cover provides a practical benchmark-with transitions into 'coping' states occurring below ∼65% of historical maxima, and further declines below ∼35% associated with 'struggling' states. Regardless of baseline morphological composition, disturbance-driven transitions toward flatter, algal-dominated reef profiles represent a convergent trajectory of functional decline-one that is likely to accelerate as disturbance regimes intensify under climate change.

Diets across age groups vary in both nutritional quality and greenhouse gas emissions, yet their relationship remains poorly understood in the context of population aging and evolving dietary patterns. We evaluated dietary emissions associated with 141 products across 22 age groups in 149 countries from 2000 to 2019, combining age-specific dietary intake from the Global Dietary Database with a consumption-based emission inventory derived from FAOSTAT. We quantified changes in emissions alongside shifts in nutritional quality and examined contributions of demographic and dietary factors. Adolescents and young adults generally had the highest per capita dietary emissions, while seniors contributed most to global emission growth, particularly in high- and upper-middle-income countries. Increased meat intake was a leading contributor to rising emissions and frequently coincided with declining nutritional quality. These findings highlight the need for dietary-emission mitigation efforts across age groups that account for demographic shifts, nutritional needs and national development contexts.

The Amazon rainforest is a key component of the Earth system, regulating regional climate, sustaining high biodiversity and carbon stocks. However, it is threatened by climate and land-use changes. In recent decades, the region has experienced intensified droughts and heatwaves, trends expected to worsen under future warming. In this study, we assess how the timing, length, and spatial distribution of the dry season across the Amazon is projected to change this century under different Shared Socioeconomic Pathways. Using a multi-model ensemble of the Coupled Model Intercomparison Project (CMIP6) weighted according to their RMSE performance, we estimate monthly water balance based on precipitation and evapotranspiration from 2000 to 2100. We calculated dry season onset, end, and length from accumulated water deficits, providing a spatially explicit characterization of seasonal dynamics. We find a significant lengthening of the dry season in 35% of the basin under low-emission scenarios (SSP1-2.6) and up to 56% under high-emission scenarios (SSP5-8.5), with increases of up to 2 months in the southern and eastern Amazon by 2100. Such changes pose major risks for forest degradation, regional water availability, and climate feedback, potentially reducing the biome's role as a carbon sink. With such large changes even under low emission, our findings demonstrate the urgent need for spatially targeted climate adaptation strategies and mitigation policies that consider future changes in seasonal water availability. While such strategies are essential to enhance societal resilience, safeguarding forest ecosystems and preserving Amazonian hydrological functions ultimately depend on ambitious efforts to reduce greenhouse gas emissions. These actions are essential not only for local and regional sustainability but also for global climate stability.

The controllable cleavage of robust imine bonds, which is a fundamental process in dynamic covalent chemistry, remains a critical challenge due to the inherent conflict between bond stability and reversibility. Although the electric field has been proven as a promising catalyst for bond cleavage, achieving the reaction under a well-defined and controllable ultrahigh electric field (UEF) is still experimentally inaccessible. Herein, the scanning tunneling microscopy break junction (STM-BJ) technique is employed as a dual-functional platform that simultaneously provides a tunable UEF (∼109 V/m) and monitors bond cleavage reactions via single-molecule conductance. The imine bonds embedded in the conjugated structure reveal negligible cleavage under field-free conditions, whereas the single-molecule conductance measurements reveal that the UEF markedly promotes cleavage in both polar and nonpolar solvents. The kinetic investigations indicate that the bond cleavage is governed by solvent polarity and electric field strength. Theoretical calculations confirm that the UEF decisively lowers the energy barrier through a cooperative hydrolysis pathway. This work provides direct evidence for the bond cleavage under an electric field and a strategy for manipulating dynamic covalent bonds.

There is a long-standing concern that land degradation reduces agricultural productivity, particularly in the long run. However, the empirical evidence on this issue remains inconclusive. Here, we present a global quantification of the link between land degradation, measured as the difference between current and historical conditions, and crop yield gaps, defined as the difference between attainable and attained yields. Our analysis establishes that, on average, a 10% increase in land degradation is associated with a roughly 2% increase in average crop yield gaps. Regionally, the loss can reach up to 6% for a 10% increase in land degradation in the globally most affected hotspots. These include northern and southern India, northeastern China, the US Midwest, as well as parts of Central and South America, particularly northern Argentina. Aggregated across the world's croplands, this translates into estimated losses of 20 million tonnes in crop production, corresponding to 52 trillion kcal, roughly the annual food calorie supply for 71 million people, and 4 billion USD in annual crop revenues.

Hemorrhagic transformation (HT) remains a life-threatening complication after acute ischemic stroke (AIS), yet no active predictive tool is available for early risk assessment. Herein, we develop an integrated triplex electrochemical aptasensing platform for the parallel and simultaneous quantification of three HT-associated biomarkers-matrix metalloproteinase-9 (MMP-9), fibronectin (FN), and plasminogen activator inhibitor-1 (PAI-1). The system enables parallel detection by inserting three independent screen-printed carbon electrodes (SPCEs) into a multi-channel electrochemical workstation, each functionalized with a distinct aptamer, allowing simultaneous quantification of MMP-9, FN, and PAI-1 within 30&#x202f;min. Each SPCE is modified with a conductive polypyrrole/poly(3,4-ethylenedioxythiophene):polystyrene sulfonate/polyvinyl alcohol hydrogel and gold nanoparticles, followed by immobilization of specific thiolated aptamers via Au-S bonds. Upon target binding, aptamer conformational changes induce a concentration-dependent decrease in differential pulse voltammetry current. The sensor achieves ultralow detection limits of 4.04&#x202f;fg/mL, 0.30&#x202f;fg/mL, and 2.79&#x202f;fg/mL for MMP-9, FN, and PAI-1, respectively, with a total assay time of 30&#x202f;min. Clinical validation using plasma from 12 AIS patients demonstrates excellent agreement with enzyme-linked immunosorbent assay (mean bias <10%) and high reproducibility (RSD <5%). This work presents the first electrochemical aptasensor for FN and PAI-1 detection and provides a clinically validated, point-of-care-compatible platform for personalized HT risk prediction in thrombolytic therapy.

Suspended sediment (SS) dynamics in semi-arid Mediterranean mountain catchments provide key insights into soil erosion processes and sediment transfer under flash flood conditions. requiring detailed monitoring of streamflow (Q) and suspended sediment concentration (SSC). The primary aim of this study was to investigate the temporal variability of suspended sediment concentration (SSC) and its relationship with hydrological responses in two representative headwater catchments of the Central High Atlas of Morocco, namely, Imi n Ouarg (7 km2; 1541 m a.s.l.) and Bou Azmou (2.7 km2; 2270 m a.s.l.). Event-based monitoring was conducted from September 2019 to 2022. Event-based monitoring of discharge and suspended sediment concentration was conducted from September 2019 to 2022. The results reveal marked differences in sediment dynamics between the two catchments. Bou Azmou, characterized by a smaller drainage area and a dominance of bare land (79%), exhibits highly reactive sediment behavior, with abrupt SSC peaks exceeding 120 g/L associated with short and intense flood events. In contrast, Imi n Ouarg, characterized by extensive open forest cover (87%), exhibits lower SSC magnitudes but pronounced temporal variability, with maximum concentrations reaching 127 g/L. This pattern suggests a more complex hydrosedimentary response involving sediment storage, delayed remobilization, and variable hillslope-channel connectivity. In both catchments, the majority of sediment transport occurs during high-flow conditions. confirming the dominant role of flash floods in sediment export. Low-flow periods contribute only marginally to the total sediment flux. The comparative analysis highlights the strong control of morphometry, altitude, and land use on sediment availability and transfer efficiency. Smaller and steeper catchments such as Bou Azmou favor rapid sediment flushing, whereas larger and more vegetated basins like Imi n Ouarg promote delayed and more heterogeneous sediment responses. These findings are consistent with sediment transport patterns reported in Mediterranean environments, where extreme hydrological events govern sediment fluxes. The novelty of this study lies in the establishment of a high-resolution field monitoring dataset in a data-scarce semi-arid mountain context, allowing for a direct comparison of SSC dynamics between two contrasted catchments under natural conditions. This work provides new insights into event-scale sediment processes in the High Atlas and contributes to improving the understanding of sediment responses to flash floods, which is essential for sustainable watershed management under increasing climatic variability.

In recent years, many high-quality reference genome sequences for arthropod species have been generated. Although most genome papers describe their protocols and metrics, no consensus exists on the data that should be included in genome reports. Here, we review current standards across seven key stages of an arthropod genome project (budgeting, sourcing and vouchering, sample preparation and sequencing, genome assembly, analysis reproducibility, databasing, and genome annotation) and identify persistent gaps in standards as well as their implementation. To assess current standards reporting in the community, we surveyed 100 arthropod genome papers published in 2024. The use of long reads to assemble highly contiguous arthropod genomes is now standard practice when adequate input DNA is available, and basic assembly contiguity and conserved gene content statistics are consistently reported. However, there is less standardization in pre- and post-assembly procedures and metrics. When comparing Darwin Tree of Life (DToL) genome notes to other journals, publications from the latter group were less likely to describe compliance with ethical collection practices, sample vouchering, post-assembly curation steps, and assembly quality metrics beyond basic contiguity and completeness values. Genome annotation practices are highly variable: some genome note formats do not explicitly require annotation, and while the reporting rate of protein-coding gene annotations is higher in non-DToL publications, the submission rate of annotations to centralized sequence databases is much lower. Our findings highlight critical opportunities to harmonize reporting standards and promote their dissemination, ensuring that future arthropod genomes are both comparable and maximally reusable for large-scale comparative and applied research.