Characterization of secondary formation of wintertime PM2.5 in eastern China: The role of relative humidity.

Ocean world plumes at Enceladus, Triton, and possibly Europa are astrobiologically significant. These active processes may transport fresh material from potentially habitable subsurface environments to the surface and atmosphere/exosphere, where they can be accessed by spacecraft and telescopic observations. However, it is currently unclear if chemical fractionation or other modification processes might occur during subsurface transport and eruption and potentially lead to changes in concentrations of habitability indicators relative to the source reservoir. To explore this phenomenon in a natural setting, we investigated the cold CO2 geysers in Green River, Utah, which have eruptions driven by volatile exsolution. We collected samples from two geysers with different vent diameters and discharge volumes and compared the chemical composition of the erupted effluent and mineralogy of evaporite deposits with their respective pre-erupted waters; we also performed geochemical modeling to reconstruct the original chemical speciation of the source waters. Observed increases in electrical conductivity for both the erupted effluents may be due to an influx of warm fluids enriched in CO2-charged brine entering the aquifer and initiating eruption via CO2 exsolution and buoyant acceleration. Modeling results indicate source waters extremely rich in dissolved CO2 with pH values significantly lower than those of erupted waters. The outgassing of CO2 and significant levels of sulfate, Na/K ratio, and acidic pH suggest that the effluent from this geysering system may serve as a natural analog for putative plume deposits on Europa. The larger geyser (Crystal) had evaporites that were carbonate-rich, while the smaller geyser (Champagne) produced evaporites dominated by sulfate minerals. Furthermore, in a sample of erupted Champagne waters cooled rapidly in vacuum to replicate a frozen plume deposit, vitreous MgSO4 was the primary constituent; this was not the main component in solution or identified in the evaporite or surrounding tufa. Overall, our observations suggest that geyser discharge volume, eruptive energy, and/or proximity to the host reservoir may all play a role in the composition of plume ejecta and surface deposits, and care should be taken in integrating both in situ and remote sensing observations to fully characterize plume deposits and make robust inferences of ocean composition. Key Words: Enceladus-Europa-Reflectance spectroscopy-Raman spectroscopy-Habitability indicator-Plume. Astrobiology xx, xxx-xxx.

Microbial life is fundamentally shaped by endogenous chemical gradients that arise within structured communities. In assemblages such as biofilms, spatial variations in pH, oxygen (O2), and reactive species create diverse microenvironments. This chemical landscape drives physiological heterogeneity, metabolic stratification, and profound tolerance to antimicrobial agents. Despite their recognized importance, recreating these dynamic microenvironments in vitro has been a persistent challenge. This perspective highlights electrochemistry as a transformative solution, offering unparalleled spatiotemporal control to sculpt the microbial microenvironment. By applying programmable potentials to microelectrodes, key chemical species can be generated or depleted on demand, creating noninvasive and dynamic chemical landscapes. We review recent advances in this field, detailing the principles and applications for electrochemically generating gradients of pH, O2, reactive species of nitric oxide (NO), and reactive oxygen species (ROS). By empowering researchers to move beyond static snapshots and dissect the real-time kinetics of microbial responses, electrochemical gradient generation opens a new frontier for understanding and manipulating the microbial world.

Assessment of leaching behavior, chemical speciation, and environmental risks of lime-treated metal-laden sludge from secondary lead smelting plant wastewater treatment

Latvian herbal medicines under the infrared lens: An FTIR-ATR dataset.

Abstract Over five decades of space exploration have revealed that the Galilean moons—Io, Europa, Ganymede, and Callisto—exhibit a wide spectrum of geological and surface features shaped by the interplay of endogenous and exogenous processes. Each moon displays distinct characteristics: Callisto’s ancient, heavily cratered terrain; Ganymede’s contrasting dark and bright regions; Europa’s extensive fracture networks; and Io’s intense volcanic activity. Their surfaces are primarily composed of water ice mixed with salts, volatiles, and organic compounds, with the exception of Io, and reflect gradients resulting from complex interactions between impact processes, resurfacing mechanisms, and radiation exposure. Surface composition offers valuable clues about potential habitability of subsurface oceans, particularly on Europa, which shows evidence of recent geological activity, liquid water-rock interactions and energy sources. This paper examines how forthcoming data from the Juice and Europa Clipper missions will significantly advance our geological understanding of the moons’ surface environments and their links to the subsurface. By providing high-resolution data and long-term observations from orbit, these missions will help confirm the distribution of subsurface liquid water reservoirs, identify key chemical species—including organics—across surfaces of varying ages, and pinpoint geologically interesting, potentially habitable sites. This information, in addition to laboratory studies or field work, among other efforts will be crucial for designing future in situ exploration to one or more moons or sample return missions, enabling a deeper investigation into the origin and evolution of the Jovian system and the search for signs of life.

Development of a mid-infrared transflection probe and in-vitro feasibility for ethanol monitoring.

Exploration of reactional parameters for palladium-catalyzed cross-coupling reaction with thermal desorption-electrospray ionization mass spectrometry.

Sodium-glucose co-transporter 2 inhibitors (SGLT2is) have consistently been shown to be beneficial in reducing the incidence rate of coronary heart disease (CHD) in diabetic patients. However, their specific pharmacological mechanisms are still unknown. Therefore, we intend to explore the mechanism of SGLT2is in patients with type 2 diabetes mellitus (T2DM) combined with CHD through a network pharmacological approach. Firstly, the Swiss Target Prediction and Drugbank databases were used to predict the targets of SGLT2is. The CHD dataset GSE113079 and T2DM dataset GSE118139 were downloaded from the gene expression omnibus database, and the differentially expressed genes (DEGs) were analyzed. Then, the predicted targets of SGLT2is intersected with the DEGs of the two diseases, and the results were used to construct the “drug-targeted-disease (D-T-D)” and protein–protein interaction networks. Gene Ontology functional analyses and Kyoto Encyclopedia of Genes and Genomes pathway were used for functional studies of target genes. Finally, molecular docking of SGLT2i with target proteins was performed using AutoDockTools software, and the docking results were verified by ELISA, RT-qPCR and western-blot experiments. Among the drug targets of SGLT2is and DEGs in T2DM and CHD, a total of 14 common gene targets exist, and these genes mainly affect the disease progression through the “chemical carcinogenesis-reactive oxygen species”,“apoptosis,” and “chemical carcinogenesis-receptor activation” pathways. Through hub gene identification, we identified 11 hub genes from these 14 targets, of which epidermal growth factor receptor (EGFR) had the highest score. Molecular docking results showed that ertugliflozin had the strongest intermolecular binding to EGFR and that ertugliflozin improved the viability of high-glucose (HG)/high-lipid combined hypoxia-reoxygenation-injured (HG/HP + H/R) cardiomyocytes and inhibited EGFR expression in cardiomyocytes. Based on network pharmacology and bioinformatics analysis, our study elucidated that EGFR is the hub gene for T2DM combined with CHD myocardial injury. Molecular docking and cell experiments further confirmed that SGLT2i-ERTU improves HG/HP + H/R myocardial cell injury by targeting EGFR. Our study deepened the pharmacological mechanism of SGLT2is in the treatment of T2DM combined with CHD and provided a new perspective and therapeutic basis for future experimental research and healthcare.

Future telescopes such as the Large Interferometer For Exoplanets (LIFE) will enable the unprecedented characterisation of the atmospheres of nearby rocky exoplanets, probing mid-infrared signatures of key molecules (e.g. CO_2, H_2O, O_3, and CH_4). Whilst 4D spatial and temporal variations of Earth as an exoplanet are below spectroscopic detection limits, such variability is strongly planet-specific. We investigated LIFE's ability to detect 4D spatial and temporal variability in the atmospheres of tidally locked exoplanets. We created daily synthetic LIFE observations of Proxima Centauri b in a 1:1 and an eccentric 3:2 spin-orbit resonance (SOR), using LIFE on spectra from daily 3D climate-chemistry model (CCM) outputs of an aquaplanet with Earth-like composition. The spectra assume an inclination of 70̧irc. sim Hemispheric distributions of temperature, clouds, and chemical species determine spectral signatures and variability with orbital phase angle. Such variability dictates the extent to which parameters (e.g. radius, temperature, or chemical abundances) can be reliably inferred from snapshot spectra at arbitrary viewing geometries. In the 1:1 SOR, the MIR spectra vary significantly with viewing geometry and indirectly probe atmospheric circulation. Nightside temperature inversions generate O_3, CO_2, and H_2O emission features, though these lie below LIFE's detection threshold; instead, O_3 features disappear at certain phase angles. In contrast, the 3:2 SOR yields a more homogeneous atmosphere with weaker phase variability but enhanced bolometric flux due to eccentric heating. Phase-resolved LIFE observations confidently distinguish between the SORs and capture seasonal O_3 variability for golden targets such as Proxima Centauri b. In the case of abiotic O_2 and O_3 build-up, the O_3 variability presents a potential false positive scenario. Hence, LIFE can disentangle different spin-orbit states and resolve 4D atmospheric variability, enabling the daily characterisation of the 4D physical and chemical state of nearby terrestrial worlds. Importantly, this characterisation requires phase-resolved rather than snapshot spectra.

Abstract The bioavailability of iron from different sources to phytoplankton, driving substantial carbon dioxide uptake of the large blooms downstream of South Georgia Island, remains unknown. Although geochemical characterization suggests that iron from glacial meltwater and groundwater is bioavailable, phytoplankton iron uptake measurements are lacking. In this study, additional to assessing iron chemical speciation and weathering processes, iron-55 uptake by a natural phytoplankton community was quantified in seawater sampled from low and high chlorophyll waters around South Georgia, to which iron from nearshore sources (glacial meltwater and groundwater) was added. Iron bioavailability depended on the chemistry of the fertilized seawater and the chemical composition of the source itself. Aggregation of dissolved organic matter in high chlorophyll water scavenged dissolved iron, making it unavailable to phytoplankton. In low chlorophyll water, as opposed to iron from groundwater, iron from glacial meltwater was bioavailable to phytoplankton and would increase carbon dioxide fixation by 80-100%.

Particulate Matter (PM) is a type of air pollution that poses risks to human health, the environment, and property. Among the various PM types, PM10 is particularly significant, as it acts as a vector for numerous hazardous trace elements that can negatively impact human health and the ecosystem. Identifying potential sources of PM10 and quantifying their impact on ambient concentrations is crucial for developing efficient control strategies to meet threshold values. Receptor modeling, which identifies sources using chemical species information derived from PM samples, has been widely used for source apportionment. In this study, PM10 samples were collected over three periods (April, May, and June 2021), each lasting 16 days, using semi-automatic dust sampling systems at two sites in Biga, Canakkale, Turkiye. The relative contributions of different source types were quantified using EPA PMF (Positive Matrix Factorization) based on 35 elements comprising PM10. As a result of the analysis, five source types were identified: crustal elements/limestone/calcite quarry (64.9%), coal-fired power plants (11.2%), metal industry (9%), sea salt and ship emissions (8.5%), and road traffic emissions and road dust (6.3%). The distribution of source contributions aligned with the locations of identified sources in the region.

Purpose This study aims to develop a new numerical framework for modelling soot formation and evolution via the soot particle size distribution (PSD) in turbulent flames. Design/methodology/approach The numerical framework couples an extended soot sectional method with a finite-rate chemistry model based on detailed chemistry, which solves primary particle and soot aggregate number densities in every section with considering turbulence–chemistry interaction. Soot aggregates and gas species are solved simultaneously with considering differential diffusion and mass exchange between soot and chemical species. A dynamic load-balancing approach with a reference mapping model is also incorporated into the numerical framework to accelerate the parallel reacting flow simulations. Findings This new numerical framework is comprehensively used to simulate soot formation and evolution in non-premixed turbulent sooting bluff body flames with different bluff body radii. With the bluff body radius increasing, the increased residence time of soot aggregates in the recirculation zone results in a significant shift of the PSD towards the larger soot aggregate side. The PSD shape always remains bimodal distribution at the centerline. Coagulation predominantly occurs at small soot aggregates, while the polycyclic aromatic hydrocarbon condensation and H-abstraction-C2H2-addition surface growth take significant effect at large soot aggregates. Originality/value Overall good quantitative and qualitative agreements of numerical results with available experimental dataset demonstrate that the new numerical framework can accurately predict the flow properties and well capture the significant soot formation and evolution processes.

Time of flight secondary ion mass spectrometry (ToF-SIMS) was used to probe the chemistry of graphene grown on copper foil substrates by chemical vapour deposition (CVD) under various growth conditions. The surface sensitivity, mass resolving power, and imaging capability of ToF-SIMS allow us to explore variations in the chemical species present on the graphene surface, as well as in three dimensions under the graphene. In this way, we can observe the impact that variations in the chemical composition of the copper foil have on the growth of the graphene; in particular, the accumulation of contaminations present in the copper foil, which has implications for the potential electrical properties of the graphene. We also observe variations in the permeation of oxygen underneath the graphene layers, resulting in oxidation of the copper substrate, depending on processing conditions employed and the chemical species present on the surface. This has implications for the gas permeation barrier properties of this material, graphene transfer mechanisms, as well as the effectiveness of using the oxidation of the copper foil as a rapid graphene quality control method. These results highlight the significance of understanding the role of trace contaminants and elemental distributions within the catalyst in conjunction with growth parameters for optimised CVD of graphene layers.

The co-contamination of arsenite (AsIII) and cadmium (Cd2+) poses a significant challenge in environmental remediation due to their divergent chemical speciation and transformation pathways. Here, a redox-active layered double oxide (MgMn-LDO) is designed, and achieves adsorption capacities of 821.7 mg g‒1 for AsIII and 1895.6 mg g‒1 for Cd2+ in their coexisting system, presenting a state-of-the-art performance. Unexpectedly, the co-adsorption system not only enhances individual adsorption capacities but also accelerates the adsorption rate by 181‒fold compared to single-component systems. The LDO undergoes a four-stage spatiotemporally ordered topological transformation, which effectively decouples the oxidation of AsIII from the adsorption of Cd2+ and reverses the conventional competitive sequence. This stepwise mechanism ensures preferential oxidation of AsIII to AsV, followed by the alteration of Cd2+ adsorption pathway to isomorphous substitution, expanding diffusion pathways and accelerating As immobilization. Large-scale experiments demonstrate this material's potential in synergistic remediation As/Cd in mining wastewater and contaminated soils.

ABSTRACT The detection of complex chemical species typically relies on cumbersome labelling techniques, expensive, sophisticated preparation steps, and influenced by environmental factors. Liquid-crystals are sensitive to external stimuli – target biomolecules, through changes in their birefringence patterns. We present a novel, cost-effective, flow-based liquid-crystal optical sensing platform for detecting penicillin in solution via penicillinase-catalysed enzymatic hydrolysis. The optical cell employs a flow-based design with PMMA matrix and immobilised penicillinase enzyme on the microgrids. The platform uses 5CB liquid-crystals, enabling the rapid detection of penicillin, resulting in observable birefringence changes under polarised microscopy. This provides a sensitive and rapid method for the detection of penicillin-G. The designed system demonstrated a detection limit of 0.1 μM for penicillin-G (with high sensitivity < 10 μM), outperforming traditional methods such as high-performance liquid chromatography for sensitivity (detection threshold of 50 μM) and response time. The optical cell setup is simple, low-cost (<$1), and exhibits high selectivity with no interference from common salts. A pre-trained convolutional neural network (GoogleNet) coupled with t-SNE visualisation is employed to classify and interpret polarised microscopy images of liquid-crystal birefringence, enabling recognition of specific molecular interaction-induced texture variations, ensuring high selectivity. The liquid-crystal-based platform offers excellent portability and shows strong prospect for on-site and field-deployable sensing applications.

The expanding diversity of synthetic chemicals is increasing ecological risk, yet many predictive models rely on single-species data and inadequately capture interspecies variability in sensitivity. We propose a generalized toxicity prediction framework (GTGT) that predicts species-resolved acute toxicity (log10LC50; LC50 in mg/L) from chemical descriptors, exposure duration, and species features─taxonomy embeddings and mitochondrial Cytochrome b (cytb) sequence embeddings─within a unified deep-learning architecture. Using a dataset of 2860 compounds and 297 fish species, GTGT outperformed representative state-of-the-art models, achieving external-test R2 = 0.83 and RMSE = 0.49. Ablation analyses show that chemical and exposure descriptors provide baseline performance, whereas biological features are critical to capture interspecies susceptibility. Comparative analyses further indicate that taxonomy embeddings encode hierarchical evolutionary relationships, while cytb sequences capture molecular divergence, providing complementary information for robust cross-species prediction. We also provide a web platform for single- and multicompound predictions across multiple fish species, enabling model-based species sensitivity distribution (SSD) curves. This framework links chemical, biological, and exposure dimensions to support SSD parametrization and derivation of protective thresholds for comparison with environmentally relevant exposures, rather than serving as a direct risk metric.

Abstract Hycean planets are hypothetical exoplanets characterized by H 2 O oceans and H 2 -rich atmospheres. These planets are high-priority targets for biosignature searches, as they combine abundant surface liquid water with easy-to-characterize H 2 -rich atmospheres. Perhaps their most unusual climate feature is convective inhibition, which can dramatically alter a planet’s temperature structure. However, so far, hycean planets have mostly been investigated using 1D models that do not account for convective inhibition, and its effects are still poorly understood. This work develops pen-and-paper theory to analyze the effects of moist convective inhibition on hycean planets. The theory is tested and verified against a 1D radiative–convective model. We show that hycean planets near the onset of convective inhibition can exhibit either bistability or oscillations, due to the inhibition layer’s trapping of heat and moisture. Meanwhile, hot hycean planets exhibit multistability, in which the inhibition layer and surface climate show multiple stable equilibria due to the lack of constraints on the water cycle inside the inhibition layer. The water cycle inside the inhibition layer is influenced by numerous processes that are challenging to resolve in 1D, including turbulent diffusion, convective overshoot, and large-scale circulations. Our results demonstrate that hycean planets have unexpectedly rich climate dynamics. Meanwhile, previous claims about hycean planets should be treated with caution until confirmed with more self-consistent 1D and 3D models; this includes the claim that K2-18b might be habitable, as well as the proposal to infer H 2 O oceans on sub-Neptunes from JWST measurements of chemical species in their upper atmospheres.

Phosphorene exhibits promising tribological application due to its layered structure that imparts intrinsic lubricating properties. Understanding the mechanisms by which oxygen and other ambient species modify phosphorene remains a key challenge, with the impact of the layer thickness and point defects still unknown. Despite its promise as a solid-state lubricant, detailed nanoscale understanding of layer-dependent defect formation, surface reactivity, and potential degradation is still limited. In particular, the possible multilayer-dependent degradation behaviour of phosphorene in the presence of common environmental species such as hydrogen (H), oxygen (O), and hydroxyl (OH) has received little attention. In this work, we perform a systematic density functional theory investigation to explore how these chemical species interact with monolayer to four-layer phosphorene, including systems with and without phosphorus vacancies. Our findings show that H, OH adsorption is energetically not favourable in any layer configurations, while O shows strong exothermic interactions across all thicknesses, regardless of the presence of defects, with the bilayer showing the most favourable interaction with these species. Structural responses, including changes in bond lengths and interlayer spacing, were quantified and found to depend on both the type of adsorbate and the number of layers. The presence of vacancies induces localized distortions but does not compromise the overall structural integrity. Bader charge calculations show charge transfer between phosphorene layers and adsorbates. Overall, our results set a foundation for further work on phosphorene by providing a detailed, layer-by-layer understanding of phosphorene's chemical reactivity in ambient environments and highlight the need to consider layer number, intrinsic defects and environmental species in models of phosphorene.

Ground-based high-resolution spectroscopic observations have identified various chemical species in the atmosphere of numerous ultra-hot Jupiters (UHJs), including neutral and ionized metals. These detections have offered valuable insights into planet formation mechanisms via abundance measurements of refractory elements. We observed the dayside thermal emission spectrum of UHJ using the high-resolution spectrographs CARMENES and PEPSI. Through our cross-correlation analysis, we detected emission signals for , AlH, , , , , , , and , marking the first detection of and AlH in an exoplanetary atmosphere. Tentative signals of , , , NaH, and were also identified. Based on those detections, we were able to perform atmospheric retrievals to constrain the thermal profile and elemental abundances of the planet’s dayside hemisphere. The retrieved temperature-pressure profile reveals a strong temperature inversion layer. The chemical free retrieval yielded a metallicity of mathrm HAT-P-70b Al i Ca ii Cr i Fe i Fe ii Mg i Mn i Ti i Al i C i Ca i Na i Ni i Fe/H = 0.38^ +0.74 _ -1.11 , while the chemical equilibrium retrieval resulted in mathrm Fe/H = 0.23^ +1.08 _ -0.98 , with both values consistent with the solar metallicity. We also tentatively found an enriched abundance of Ni, which could result from the accretion of Ni-rich planetesimals during the planet’s formation. On the other hand, elements with condensation temperatures above 1400,K (e.g., Ca, Ti, and V) appear to be slightly depleted, possibly due to cold-trapping on the planet’s nightside. However, Al, with the highest condensation temperature at 1653,K, displays a solar-like abundance, which might reflect the formation-related enrichment of Al. Our retrieval indicates extremely high volume mixing ratios of metal ions ( and ), which are significantly inconsistent with predictions from chemical equilibrium models. This disequilibrium suggests that the atmosphere is likely undergoing significant hydrodynamic escaping, which enhances the atmospheric density at high altitudes where the ionic lines are formed. Fe ii Ca ii