Mechanisms controlling spatial variability of geogenic ammonium in coastal aquifers: Insights from Holocene sedimentary evolution.

The contamination of groundwater with geogenic ammonium (NH) across various geological backgrounds has garnered significant attention, particularly in coastal aquifer systems. However, there remains a gap in our understanding of the mechanisms governing the spatial variability of NH in coastal groundwater at a macroscopic scale. In this study, we collected the sediment samples from two boreholes corresponding to high-NH-N and low-NH-N groundwater.

Progress on ancient DNA investigation of Late Quaternary mammals in China.

It has been more than 40 years since the beginning of exploring the genetic composition of ancient organisms from the perspective of ancient DNA. In the recent 20 years, with the development and application of high-throughput sequencing technology platforms and the improved efficiency of retrieving highly fragmented DNA molecules, ancient DNA research moved forward to a brand-new era of deep-time paleogenomics. It not only solved many controversial phylogenetic problems, enriched the migration and evolution details of various organisms including humans, but also launched exploration of the molecular responses to climate changes in terms of "whole genomic-big data-multi-species" level.

Numeric uptake drives nanoplastic toxicity: Size-effects uncovered by toxicokinetic-toxicodynamic (TKTD) modeling.

Predicting nanoplastic bioaccumulation and toxicity using process-based models is challenging due to the difficulties in tracing them at low concentrations. This study investigates the size-dependent effects of nanoplastic exposure on Daphnia magna using a toxicokinetic-toxicodynamic (TKTD) model. Palladium-doped fluorescent nanoplastics in three sizes (30-nm, 66-nm, 170-nm) were tested at two numeric exposure concentrations.

Interactions between phosphate and arsenic in iron/biochar-treated groundwater: Corrosion control insights from column experiments.

An increasing number of studies have reported the coexistence of arsenic (As) and phosphorus at high concentrations in groundwater, which threatens human health and increases the complexity of groundwater remediation. However, limited work has been done regarding As interception in the presence of phosphate in flowing systems. In this study, a series of experiments were conducted to evaluate the interactions between phosphate and As during As removal by iron (Fe)-based biochar (FeBC).

Assessment of groundwater chemistry to predict arsenic contamination from a canal commanded area: applications of different machine learning models.

Groundwater arsenic (As), contamination is a significant issue worldwide including China and Pakistan, particularly in canal command areas. In this study, 131 groundwater samples were collected, and three machine learning models [Random Forest (RF), Logistic Regression (LR), and Artificial Neural Network (ANN)] were employed to predict As concentration. Descriptive statistics helped to conclude that all of the samples were inside the permitted limit of WHO for pH, Ca, Mg, Turbidity, Cl, K, Na, SO, NO, F and beyond limit of WHO for EC, HCO, TDS, and As.

State-space modelling using wastewater virus and epidemiological data to estimate reported COVID-19 cases and the potential infection numbers.

The current situation of COVID-19 measures makes it difficult to accurately assess the prevalence of SARS-CoV-2 due to a decrease in reporting rates, leading to missed initial transmission events and subsequent outbreaks. There is growing recognition that wastewater virus data assist in estimating potential infections, including asymptomatic and unreported infections. Understanding the COVID-19 situation hidden behind the reported cases is critical for decision-making when choosing appropriate social intervention measures.

Development of a Predictive Model for N-Dealkylation of Amine Contaminants Based on Machine Learning Methods.

Amines are widespread environmental pollutants that may pose health risks. Specifically, the N-dealkylation of amines mediated by cytochrome P450 enzymes (P450) could influence their metabolic transformation safety. However, conventional experimental and computational chemistry methods make it difficult to conduct high-throughput screening of N-dealkylation of emerging amine contaminants.

Analysis of Acute and Short-Term Fluoride Toxicity in Zebrafish Embryo and Sac-Fry Stages Based on Bayesian Model Averaging.

Acute and short-term toxicity tests are foundational to toxicology research. These tests offer preliminary insights into the fundamental toxicity characteristics of the chemicals under evaluation and provide essential data for chronic toxicity assessments. Fluoride is a common chemical in aquatic environments; however, the findings of toxicological data, such as LC for aquatic organisms, often exhibit inconsistency.

Biological and Chemical Processes of Nitrate Reduction and Ferrous Oxidation Mediated by MR-1.

Iron, Earth's most abundant redox-active metal, undergoes both abiotic and microbial redox reactions that regulate the formation, transformation, and dissolution of iron minerals. The electron transfer between ferrous iron (Fe(II)) and ferric iron (Fe(III)) is critical for mineral dynamics, pollutant remediation, and global biogeochemical cycling. Bacteria play a significant role, especially in anaerobic Fe(II) oxidation, contributing to Fe(III) mineral formation in oxygen-depleted environments.

Irradiation and DOM mediate lead release from polyvinyl chloride microplastics in natural surface water.

Polyvinyl chloride (PVC) is a widely used plastic, but the potential risk of heavy metal additive release from PVC microplastics (MPs) has not been fully explored. This study evaluates the release of lead (Pb) from recycled PVC MPs under natural conditions. The released Pb concentration in the dark was 1079.

A Collaborative and Scalable Geospatial Data Set for Arctic Retrogressive Thaw Slumps with Data Standards.

Arctic permafrost is undergoing rapid changes due to climate warming in high latitudes. Retrogressive thaw slumps (RTS) are one of the most abrupt and impactful thermal-denudation events that change Arctic landscapes and accelerate carbon feedbacks. Their spatial distribution remains poorly characterised due to time-intensive conventional mapping methods.

Enhancement of Zn adsorption on coal fly ash-based geopolymer with steel slag incorporation: Leaching behavior and performance insights.

Industrial solid wastes like coal fly ash (CFA) and steel slag pose environmental challenges, while the remediation of heavy metal-contaminated water remains a global priority. This study investigates the impact of incorporating steel slag during the synthesis of CFA-based geopolymers (CFAG) on the leaching characteristics of inherent heavy metals in CFA and the Zn adsorption performance of CFAG. Leaching experiments show geopolymerization effectively immobilizes heavy metals including Fe, Cr, As, Cd, and Ti in CFA while having little effect on Mn, V, and Ni.

Acetochlor degradation in anaerobic microcosms with hyporheic sediments: Insights from biogeochemical data, transformation products, and isotope analysis.

Steep redox gradients and diverse microbial communities in the anaerobic hyporheic zone create complex pathways for the degradation of herbicides, often linked to various terminal electron-accepting processes (TEAPs). Identifying the degradation pathways and their controlling factors under various TEAPs is of great significance for understanding mechanisms of water purification in the hyporheic zone. However, current research on herbicides in this area remains insufficient.

EMT-Induced Morphological Variations on Living Cell Membrane Surface.

Epithelial-mesenchymal transition (EMT) is a drastic and important cellular process by which epithelial cells acquire a mesenchymal phenotype. Herein, we evaluated EMT-induced membrane variations using scanning ion conductance microscopy (SICM), which allows noninvasive nanoscale visualization. The results showed that the number and size of ruffles on the living cell surface decreased as the EMT progressed.

Climate change projections for Diamer Division in lesser Himalayas using multi-global climate model ensemble.

Pakistan, like many other regions around the world, is experiencing the impacts of climate change, particularly in its northern region. These changes have adverse impacts on ecosystems and biodiversity. Herein, we have investigated future projections of temperature and precipitation trends for three periods historical (HT = 1975-2005), near-term (NT = 2010-2029), and mid-term (MT = 2030-2050) using climate model intercomparison projects along with global climate models (GCMs) including RCP4.

Night flight facilitates late breeding catch-up in a long-distance migratory seabird.

Long-distance migrants must optimise their timing of breeding to capitalise on resources at both breeding and over-wintering sites. In species with protracted breeding seasons, departing earlier on migration might be advantageous, but is constrained by the ongoing breeding attempt. Here we investigated how breeding timing affects migratory strategies in the Manx shearwater (Puffinus puffinus), a trans-hemispheric migratory seabird with large temporal variation in the onset of breeding.

Accumulation of lipophilic and proteinophilic halogenated organic pollutants (HOPs) in the different types of feathers of laying hens.

This study investigated the bioaccumulation of halogenated organic pollutants (HOPs) in three types of feathers from laying hens through exposure experiments. The HOPs included lipophilic polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), as well as proteinophilic perfluoroalkyl carboxylic acids (PFCAs). Concentrations of PCBs, PBDEs, and short-chain PFCAs (≤8) were significantly higher in the body feathers than in the primary feathers, while long-chain PFCAs (>8) showed no significant differences among primary, tail, and body feathers.

Quantifying the Interactions and Cumulative Effects of Multiple Stressors on Salmonids.

The cumulative effects of human activities and natural pressures pose significant threats to ecosystem functioning and global biodiversity. Assessing the cumulative impact of multiple stressors-whether acting simultaneously or sequentially and directly or indirectly-is challenging due to their complex interactions. Consequently, these interactions may be unintentionally overlooked or disregarded in management decisions.

Bisphenol A and its potential mechanism of action for reproductive toxicity.

Bisphenol A (BPA) is an organic synthetic chemical used worldwide. Billions of pounds of BPA are produced annually through industrial processes to be used in commercial products, making human exposure to BPA ubiquitous. Concerns have been raised due to the potential adverse health effects of BPA, specifically in vulnerable populations, such as pregnant persons and children.

Alkane degradation coupled to Fe(III) reduction mediated by Gram-positive bacteria.

Petroleum hydrocarbon contamination, such as n-alkanes, poses a significant global threat to ecosystems and human health. Microbial remediation emerges as a promising strategy for addressing this issue through both aerobic and anaerobic processes. Notably, the majority of anaerobic hydrocarbon degraders identified to date are Gram-negative bacteria.

[Hydrochemical Characteristics of Surface Water and Groundwater in Shiyan Urban Area and Sources of Nitrate].

Nitrate pollution in water bodies is a worldwide environmental problem, and identifying the sources of nitrate is of great significance to guarantee the sustainable use of water resources. A variety of water chemistry indicators and nitrate nitrogen and oxygen isotopes （N-NO and O-NO） were used to analyze the water chemistry characteristics of water bodies in Shiyan to identify the sources of nitrate in the water bodies and to calculate the contribution rate of nitrate from different pollution sources of the water bodies using the SIMMR model. The results showed that the hydrochemical types of surface water and groundwater in the study area were dominated by the HCO-Ca·Mg type, and the formation of nitrate in the water body was mainly affected by nitrification, with non-obvious denitrification.

A Novel Organophosphate Ester, Tris(2,4-di-butylphenyl) Phosphate, Induced Reproductive Toxicity in Male Zebrafish at Environmentally Relevant Concentrations.

As a novel organophosphate ester (NOPE), tris(2,4-di-butylphenyl) phosphate (TDtBPP) has attracted significant attention due to its unexpectedly high detection in natural environments. However, the ecological toxic effects of environmentally relevant concentrations of TDtBPP in organisms remain entirely unknown. In this study, 1 month old zebrafish were exposed to 0, 50, 500, or 5000 ng/L TDtBPP for 150 days, and the reproductive toxicity in male fish was evaluated.

Quantification and source apportionment of atmospheric oxidation capacity in urban atmosphere by considering reactive chlorine species and photochemical loss of VOCs.

Atmospheric oxidation capacity (AOC) reflects the potential of the atmosphere in converting primary pollutants into secondary aerosols and ozone (O). In this study, the AOC at an urban supersite in Wuhan, a megacity in central China, was quantified by considering the reactions of volatile organic compounds (VOCs) and carbon monoxide (CO) with atmospheric oxidants (OH, NO, O, and Cl). Photochemical loss of total VOCs (13.