Microplastic pollution in terrestrial ecosystems threatens to destabilize large soil carbon stocks that help to mitigate climate change. Carbon-based substrates can release from microplastics and contribute to terrestrial carbon pools, but how these emerging organic compounds influence carbon mineralization and sequestration remains unknown. Here, microcosm experiments are conducted to determine the bioavailability of microplastic-derived dissolved organic matter (MP-DOM) in soils and its contribution to mineral-associated carbon pool.
View Article and Find Full Text PDFThe potential of microplastics to act as a vector for anthropogenic contaminants is of rising concern. However, directly quantitatively determining the vector effects of microplastics has been rarely studied. Here, we present a dual-dosing method that simulates the chemical bioaccumulation from soil and microplastics simultaneously, wherein unlabeled hydrophobic organic contaminants (HOCs) were spiked in the soil and their respective isotope-labeled reference compounds were spiked on the polyethylene microplastics.
View Article and Find Full Text PDFMicroplastics alter niches of soil microbiota by providing trillions of artificial microhabitats, termed the "plastisphere." Because of the ever-increasing accumulation of microplastics in ecosystems, it is urgent to understand the ecology of microbes associated with the plastisphere. Here, we present a continental-scale study of the bacterial plastisphere on polyethylene microplastics compared with adjacent soil communities across 99 sites collected from across China through microcosm experiments.
View Article and Find Full Text PDFThe wide application of plastics has led to the ubiquitous presence of nanoplastics and microplastics in terrestrial environments. However, few studies have focused on the mechanism underlying the effects of plastic particles on soil microbiomes and resistomes, especially the differences between nanoplastics and microplastics. This study investigated the microbiome and resistome in soil exposed to polystyrene microplastics (mPS) or nanoplastics (nPS) through 16S rRNA and shotgun metagenomic sequencing.
View Article and Find Full Text PDFThe effect of long term exposure to low concentrations of environmental pollutants on hepatic disorders is a major public health concern worldwide. Polycyclic aromatic hydrocarbons (PAHs) are a class of persistent organic pollutants. In recent years, an increasing number of studies have focused on the deleterious effects of low concentrations of PAHs in the initiation or exacerbation of the progression of chronic liver disease.
View Article and Find Full Text PDFAlthough in vitro simulation and in vivo feeding experiments are commonly used to evaluate the carrier role of microplastics in the bioaccumulation of toxic chemicals, there is no direct method for quantitatively determining their vector effect. In this study, we propose a dual-labeled method based on spiking unlabeled hydrophobic organic contaminants (HOCs) into soils and spiking their respective isotope-labeled reference compounds into microplastic particles. The bioaccumulation of the unlabeled and isotope-labeled HOCs in earthworms was compared.
View Article and Find Full Text PDFColonoscopy is the gold standard method for investigating the gastrointestinal tract. Localizing the polyps in colonoscopy images plays a vital role when doing a colonoscopy screening, and it is also quite important for the following treatment, e.g.
View Article and Find Full Text PDFBroad topics of the plastisphere in various environments are reviewed, including its methodologies, diversity, functionality, and outlook.
View Article and Find Full Text PDFUnderstanding the excited state behavior of isomeric structures of thiolate-protected gold nanoclusters is still a challenging task. In this paper, based on grand unified model and ring model for describing thiolate-protected gold nanoclusters, we have predicted four isomers of Au(SR)nanoclusters. Density functional theory calculations show that the total energy of one of the predicted isomers is 0.
View Article and Find Full Text PDFStraw incorporation is typically employed to enhance the nutrient content of soil and promote crop growth in intensive agricultural systems. Despite studies regarding the effects of straw incorporation on soil microbial communities, the underlying mechanisms of its effect on community co-occurrence interactions and assembly processes remain poorly understood. Herein, soil samples with or without straw incorporation were collected across a latitudinal gradient from north to central China.
View Article and Find Full Text PDFBiodegradable polymers are promoted as promising alternatives for conventional non-degradable plastics, but they may also negatively impact soil ecosystems. Here, we estimated the effects of biodegradable (polylactide (PLA) and polybutylene succinate (PBS)) and non-biodegradable (polyethylene (PE) and polystyrene (PS)) microplastics at a concentration of 1% (w/w) on dissolved organic matter (DOM) in two soil types, a black soil (BS) and a yellow soil (YS), by using fluorescence excitation-emission matrix spectroscopy and ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). PBS significantly increased the contents of soil dissolved organic carbon (DOC) and the relative intensities of protein-like components.
View Article and Find Full Text PDFThe increasing One-Health concept calls for a more in-depth understanding of the dissemination of antibiotic resistance in plant microbiomes. While there is considerable published evidence that microplastics can promote the spread of antibiotic resistance genes (ARGs) in the environment, whether and how microplastics impact the plant endophytic resistome are largely unknown. Here we examined the ARGs along the soil-root continuum of maize and wheat under the pressure of microplastics.
View Article and Find Full Text PDFHeteroatom substitution of gold nanoclusters enables precise tuning of their physicochemical properties at the single-atom level, which has a significant impact on the applications related to excited states including photovoltaics, photocatalysis and photo-luminescence. To this end, understanding the effect of metal exchange on the structures, electronic properties and photoexcited dynamic behavior of nanoclusters is imperative. Combining density functional theory with time-domain nonadiabatic molecular dynamics simulations, herein we explored the effect of metal replacement on the electronic and vibrational properties as well as excited-state dynamics of ligand-protected MAu(SR) (M = Pd, Pt, Cd, and Hg) nanoclusters.
View Article and Find Full Text PDFThe gradual accumulation of microplastics has aroused increasing concern for the unique niche, termed "plastisphere." As research so far has focused on their characteristics in aquatic ecosystems, our understanding of the colonization and assembly of the attached bacterial communities on microplastics in soil ecosystems remains poor. Here, we aimed to characterize the plastisphere microbiomes of two types of microplastics (polylactic acid [PLA] and polyethylene [PE]) differing in their biodegradability in two different soils.
View Article and Find Full Text PDFBiodegradable plastics have emerged as an ecological alternative to conventional petroleum-based plastics. Despite the recent advances in the effects of conventional microplastic on soil ecosystems, the ecological impact of biodegradable microplastics in soil environments remains poorly understood. Here, we performed soil microcosms with conventional (polyethylene and polystyrene) and biodegradable (polybutylene succinate and polylactic acid) microplastics to estimate their effects on the success patterns, co-occurrence networks, and the assembly mechanisms of soil bacterial communities.
View Article and Find Full Text PDFConcerns about the ecological safety of both conventional and biodegradable microplastics have grown due to the inadequate end-of-life treatments of plastics. In this study, the effects of conventional and biodegradable microplastics on the spread of antibiotic resistance genes (ARGs) and virulence factors (VFs) were estimated in a soil microcosm experiment. The gene profiles and their respective bacterial hosts in soil were evaluated by metagenomic sequencing methods.
View Article and Find Full Text PDFMicroplastics have been proposed as emerging threats for terrestrial systems as they may potentially alter the physicochemical/biophysical soil environments. Due to the variety of properties of microplastics and soils, the microplastic-induced effects in soil ecosystems are greatly manifold. Here, we studied effects of three polymer microplastics (polyamide-6, polyethylene, and polyethylene terephthalate) on soil properties with four different soil types.
View Article and Find Full Text PDFEnvironmental concerns with liberal petroleum-based plastic use have led to demand for sustainable biodegradable alternatives. However, the inadequate end-of-life treatment of plastics may emit microplastics, either conventional or biodegradable, to the terrestrial environment. It is essential to evaluate the possible effects of conventional and biodegradable microplastics on the composition and function of soil microbial communities.
View Article and Find Full Text PDFIncreasing research has recognized that the ubiquitous presence of microplastics in terrestrial environments is undeniable, which potentially alters the soil ecosystem properties and processes. The fact that microplastics with diverse characteristics enter into the soil may induce distinct effects on soil ecosystems. Our knowledge of the impacts of microplastics with different polymers, shapes, and concentrations on soil bacterial communities is still limited.
View Article and Find Full Text PDFA growing body of evidence suggests that microplastics may be colonized with a unique microbiome, termed 'plastisphere', in aquatic environments. However, the deep mechanisms (deterministic and/or stochastic processes) underlying the community assembly on microplastics are still poorly understood. Here, we took the estuary of Hangzhou Bay (Zhejiang, China) as an example and examined the assembly mechanisms of bacterial communities in water and microplastic samples.
View Article and Find Full Text PDFClathrate hydrates are crystalline solid compounds consisting of a water caged framework and guest molecules such as CH, CH, and CO. Understanding the phase equilibrium conditions of hydrates is significantly important for the industrial exploitation and experimental synthesis of hydrates. Based on the correct description of the intermolecular noncovalent interactions of clathrate hydrates with vdW-DF2, we studied the crystal structures and the chemical potential phase diagrams of sII hydrates encapsulated with CO molecules to provide a deep understanding of the stability mechanism of hydrates.
View Article and Find Full Text PDFGrowing evidence have demonstrated that microplastics in the marine ecosystem can provide novel substrates for biofilm formation, potentially facilitating the spread of antibiotic resistance. However, the occurrence of antibiotic resistance genes (ARGs) in the biofilm on microplastics has not been fully explored. This study used the metagenomic data of biodegradable and non-biodegradable microplastics staged at a coastal lagoon in the northern Gulf of Mexico to profile the ARGs and their bacterial hosts.
View Article and Find Full Text PDFThe role of microplastics as a carrier in the bioaccumulation of hydrophobic organic contaminants (HOCs) in soil organisms is poorly understood. Two environmentally relevant scenarios, including earthworm exposed to contaminated soil amended with clean microplastics (S1) and clean soil introduced with precontaminated microplastics (S2), were simulated to estimate the importance of microplastics in bioaccumulation. Three polychlorinated biphenyls and polyethylene particles with different sizes were employed.
View Article and Find Full Text PDFAntibiotic residues are major contaminants in milk because of their use in agriculture and animal husbandry. In particular, streptomycin, an aminoglycoside antibiotic, is a potential risk to consumers because of its ototoxicity, anaphylaxis, and growth inhibition. Herein, monoclonal antibodies for streptomycin were conjugated with europium microspheres to serve as detection probes for the development of a chromatographic time-resolved fluoroimmunoassay to detect streptomycin residues in milk.
View Article and Find Full Text PDFAlthough the ubiquitous presence of microplastics in various environments is increasingly well studied, knowledge of the effects of microplastics on ambient microbial communities is still insufficient. To estimate the response of soil bacterial community succession and temporal turnover to microplastic amendment, a soil microcosm experiment was carried out with polyethylene microplastics. The soil samples under control and microplastic amendment conditions were collected for sequencing analysis using Illumina MiSeq technology.
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