Publications by authors named "Hong-hu Zeng"

Quantitative structure-activity relationships (QSARs) have been used to predict mixture toxicity. However, current research faces gaps in achieving accurate predictions of the mixture toxicity of azole fungicides. To address this gap, the application of machine learning (ML) algorithms has emerged as an effective strategy.

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  • - Antibiotics and triazole fungicides in natural water systems create complex mixtures that can impact aquatic ecosystems, making it important to assess their combined toxicity.
  • - A study tested 75 different combinations of antibiotics and fungicides on the algae Auxenochlorella pyrenoidosa and utilized machine learning models to analyze their toxic effects.
  • - The kernel k-nearest neighbors (KKNN) model was the most effective for predicting toxicity, while the random forest (RF) model accurately classified the mixtures, providing valuable insights for future risk assessments.
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  • - Ampicillin (AMP) and cefazolin (CZO) are widely used antibiotics known for high ecological toxicity, and their combination can create a synergistic effect that is particularly harmful to aquatic organisms like algae.
  • - A study investigated how different concentrations of AMP and CZO affect algae, revealing that exposure led to significant growth inhibition linked to increased reactive oxygen species (ROS) and disruptions in metabolic processes.
  • - Transcriptomic analyses showed that the combination of AMP and CZO affects key biological functions, damaging both photosynthesis and antioxidant systems, leading to a deeper understanding of their environmental risks.
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  • - Understanding how environmental pollutants interact is crucial for assessing their harmful effects on aquatic ecosystems, but previous research often lacks insight into the underlying biochemical and physiological mechanisms.
  • - The study focused on the toxic effects of three azole fungicides—cyproconazole (CYP), imazalil (IMA), and prochloraz (PRO)—on the alga Auxenochlorella pyrenoidosa, finding that higher concentrations reduce chlorophyll content, increase total protein suppression, and negatively impact growth.
  • - The interactions between the pollutants led to varying toxicity effects depending on their concentrations, with low concentrations showing antagonistic effects and high concentrations exhibiting synergistic effects, emphasizing the need for deeper understanding of these biochemical interactions in
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A magnetic activated carbon adsorbent named NiFeO@AC was synthesized by modifying activated carbon with NiFeO and used for the adsorption of Cr(Ⅵ) ions from waste water. The influencing factors, adsorption kinetics, and adsorption isotherms of Cr(Ⅵ) adsorption by the adsorbent were investigated. The results showed that the removal rate of Cr(Ⅵ) adsorption by NiFeO@AC reached 96.

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  • Azole fungicides can be toxic to the environment, and their combined effects in mixtures are not yet fully understood; this study analyzed 225 binary and 126 multi-component mixtures on the algae Chlorella pyrenoidosa.* -
  • The toxicity levels varied significantly among the azole fungicides and their mixtures, with some mixtures showing high toxicity, especially those including epoxiconazole, while their combined effect often resulted in additive, synergistic, or antagonistic interactions.* -
  • At lower concentrations (10% effect), the majority of mixtures (69.23%) exhibited additive toxicity, while at higher concentrations (50% effect), the interactions shifted, with 55.84% showing either synergistic or antagon
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  • The study focuses on improving nitrogen removal from ammonium-rich wastewater using a novel zeolite membrane biological reactor (ZMBR) that enhances partial nitritation (PN) combined with anammox.
  • The ZMBR outperforms traditional membrane biological reactors (MBRs) by tolerating higher nitrogen loading rates and achieving better nitrite production rates, leading to effective nitrogen removal.
  • High-throughput sequencing revealed a significant presence of a beneficial bacteria, Kuenenia stuttgartiensis, in the granular sludge, indicating its potential for efficient nitrogen removal and improved settleability.
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Eucalyptus biochar(BC) was prepared and potassium permanganate was used to modify the biochar(KBC). Static adsorption experiments on Pb(Ⅱ) in aqueous solution were carried out to investigate the effects of pH, adsorbent dosing, adsorption time, temperature, and initial concentration on the adsorption of Pb(Ⅱ). The results showed that the optimum pH was 5 while the adsorption reached saturation after 6 h.

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The potential toxicity of haloacetic acids (HAAs), common disinfection by products (DBPs), has been widely studied; but their combined effects on freshwater green algae remain poorly understood. The present study was conducted to investigate the toxicological interactions of HAA mixtures in the green alga Raphidocelis subcapitata and predict the DBP mixture toxicities based on concentration addition, independent action, and quantitative structure-activity relationship (QSAR) models. The acute toxicities of 6 HAAs (iodoacetic acid [IAA], bromoacetic acid [BAA], chloroacetic acid [CAA], dichloroacetic acid [DCAA], trichloroacetic acid [TCAA], and tribromoacetic acid [TBAA]) and their 68 binary mixtures to the green algae were analyzed in 96-well microplates.

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Currently, few studies have investigated the joint toxicity mechanism of azole fungicides at different exposure times and mixed at the relevant environmental concentrations. In this study, three common azole fungicides, namely, myclobutanil (MYC), propiconazole (PRO), and tebuconazole (TCZ), were used in studying the toxic mechanisms of a single substance and its ternary mixture exposed to ambient concentrations of Chlorella pyrenoidosa. Superoxide dismutase (SOD), catalase (CAT), chlorophyll a (Chla), and total protein (TP), were used as physiological indexes.

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Sulfonamide antibiotics are contaminants of emerging concern (CEC). These CECs raise considerable alarm because they are commonly present in water environments. Studies on the environmental existence of CECs in karst areas of Guilin (Southern China) have yet to be reported.

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Aromatic halogenated chemicals are an unregulated class of byproducts (DBPs) generated from disinfection processes in the water environment. Information on the toxicological interactions, such as antagonism and synergism, present in DBP mixtures remains limited. This study aimed to determine the toxicological effects of aromatic halogenated DBP mixtures on the freshwater bacterium Vibrio qinghaiensis sp.

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A suitable model to predict the toxicity of current and continuously emerging disinfection by-products (DBPs) is needed. This study aims to establish a reliable model for predicting the cytotoxicity of DBPs to Chinese hamster ovary (CHO) cells. We collected the CHO cytotoxicity data of 74 DBPs as the endpoint to build linear quantitative structure-activity relationship (QSAR) models.

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Antibiotics and pesticides may exist as a mixture in real environment. The combined effect of mixture can either be additive or non-additive (synergism and antagonism). However, no effective predictive approach exists on predicting the synergistic and antagonistic toxicities of mixtures.

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Six common heavy metals (Ni, Fe, Zn, Pb, Cd, and Cr) in the water environment were selected to present five groups of binary mixture systems (Ni-Fe, Ni-Zn, Ni-Pb, Ni-Cd, and Ni-Cr) through a direct equipartition ray design. Microplate toxicity analysis based on Chlorella pyrenoidosa measured the 96-h joint toxicities of the binary mixtures. Toxicity interaction of the binary mixture was analyzed by comparing the observed toxicity data with the reference model (concentration addition).

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Two-stage prediction (TSP) model had been developed to predict toxicities of mixtures containing complex components, but its prediction power need to be further validated. Six phenolic compounds and six heavy metals were selected as mixture components. One mixture (M1) was built with equivalent-effect concentration ratio and four mixtures (M2-M5) were designed with fixed concentration ratio.

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The purpose of this study is to compare microbial number, microbial biomass as well as soil enzyme activity between paddy field and dryland originated karst wetland ecosystems. The soil samples (0-20 cm) of uncultivated wetland, paddy field and dryland were collected in Huixian karst cave wetland, Guilin, China. Microbial numbers and biomass were detected using dilute plate incubation counting and chloroform fumigation-extraction, respectively.

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The nature of most environmental contaminants comes from chemical mixtures rather than from individual chemicals. Most of the existed mixture models are only valid for non-interactive mixture toxicity. Therefore, we built two simple linear regression-based concentration addition (LCA) and independent action (LIA) models that aim to predict the combined toxicities of the interactive mixture.

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The individual toxicities of five organophosphorus pesticides (dichlorvos, parathion, methyl parathion, malathion and dimethoate) to Daphnia magna were investigated in 24-h immobilization experiments. Using these toxicity data, their combined toxicities were measured in pesticide mixtures designed using either 'equivalent-effect concentration ratios' or 'uniform-design concentration ratios'. The toxicities of mixtures of similarly or dissimilarly acting toxicants are often predicted from the individual toxicities of the component compounds, using one of two distinct biometric models: concentration addition (CA) or independent action (IA).

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  • - The study compared acute toxicity levels of copper for Daphnia magna using predictions from the biotic ligand model (BLM) and actual measurements taken from water samples in Liaohe River and Taihu Lake during wet and dry seasons.
  • - BLM predicted copper toxicity values ranged from 232.75-411.49 µg/L, while measured values were lower, at 134.55-350.00 µg/L, with better consistency at three sites but discrepancies noted at one site.
  • - The water effect ratios (WERs) were all above 1, indicating increased copper toxicity, especially in dry season samples, potentially due to copper interacting with dissolved organic matter that lowered its toxicity in wet conditions.
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