Dynamics of antibiotic resistance genes and bacterial community structure within substrate biofilms.

Biofilms that develop on the surface of substrates are critical for treating wastewater. The accumulation of antibiotic resistance genes (ARGs) within these biofilms is particularly noteworthy. Despite their importance, studies that focus on biofilms attached to substrate surfaces remain scarce.

Chlormequat inhibits Vallisneria natans growth and shapes the epiphytic biofilm microbial community.

Submerged macrophytes can overgrow and negatively affect freshwater ecosystems. This study aimed to investigate the use of chlormequat (CQ) to regulate submerged Vallisneria natans growth as well as its impact on the microbial community of epiphytic biofilms. V.

Microbial communities and mobile genetic elements determine the variations of antibiotic resistance genes for a continuous year in the urban river deciphered by metagenome assembly.

Antibiotic resistance genes (ARGs) have become emerging environmental contaminants influenced by intricate regulatory factors. However, there is a lack of comprehensive studies on the evolution and distribution of ARGs over a full year in urban rivers, which serve as significant reservoirs of ARGs due to dynamic human activities. In this study, we conducted a 12-month metagenomic assembly to explore the microbial communities, ARGs, mobile genetic elements (MGEs) coexisting with ARGs, ARGs hosts, and the impact of environmental factors.

Coupled effects of redox-active substances and microbial communities on reactive oxygen species in rhizosphere sediments of submerged macrophytes.

Reactive oxygen species (ROS) play crucial roles in element cycling and pollutant dynamics, but their variations and mechanisms in the rhizosphere of submerged macrophytes are poorly investigated. This study investigated the light-dark cycle fluctuations and periodic variations in ROS, redox-active substances, and microbial communities in the rhizosphere of Vallisneria natans. The results showed sustained production and significant diurnal fluctuations in the O and •OH from 27.

The coupling effect promotes superoxide radical production in the microalgal-fungal symbiosis systems: Production, mechanisms and implication for Hg(II) reduction.

Redox transformation of mercury (Hg) is critical for Hg exchange at the air-water interface. However, the superoxide radicals (O) contribution of microalgal-fungal symbiotic systems in lake water to Hg(II) reduction is mainly unknown. Here, we studied the enhanced potential for O production by the coupling effect between microalgae and fungi.

Total phosphorus speciation and transport flux dynamics driven by tidal variations in the Shuidong Bay coastal water during summer, China.

Phosphorus (P) is a vital nutrient for the growth of marine organisms. Tidal cycle had major influence on various biogeochemical parameters of the bay and changed nutrients input with the ebb and flow of the tide. Seawater was collected by synchronous continuous observation during summer in 2021, to investigate tide drives total phosphorus (TP) variation on the concentration, speciation and exchange flux between Shuidong Bay (SDB) and South China Sea (SCS).

Evolution and distribution of antibiotic resistance genes in submerged macrophytes and biofilm systems: From seasonal monitoring to mesocosm experiments.

The aquatic ecosystem has been extensively investigated as a hotspot for the spread of antibiotic resistance genes (ARGs); yet, the evolution and distribution of ARGs profiles in submerged macrophytes biofilms and surrounding water remained unclear. In this study, the dynamic distribution and seasonal variations of microbial communities and ARGs profiles were investigated, alongside their assembly processes and mutual interactions. Bacitracin and multidrug resistance genes were predominant, constituting more than 60% of the total ARGs abundance.

Effects of typhoon events on coastal hydrology, nutrients, and algal bloom dynamics: Insights from continuous observation and machine learning in semi-enclosed Zhanjiang Bay, China.

Typhoons can induce variations in hydrodynamic conditions and biogeochemical processes, potentially escalating the risk of algal bloom occurrences impacting coastal ecosystems. However, the impacts of typhoons on instantaneous changes and the mechanisms behind typhoon-induced algal blooms remain poorly understood. This study utilized high-frequency in situ observation and machine learning model to track the dynamic variations in meteorological, hydrological, physicochemical, and Chlorophyll-a (Chl-a) levels through the complete Typhoon Talim landing in Zhanjiang Bay (ZJB) in July 2023.

Effects of terrestrial input on heavy metals in Zhanjiang Bay, a typical subtropical bay in the South China Sea.

Understanding the influence of terrestrial inputs on heavy metals in bays is crucial for the environmental protection of regional estuaries and coastal systems. In this study, the concentrations, temporal and regional distribution characteristics, and fluxes of heavy metals (Cr, Cu, Zn, Cd, Pb) in the surface seawater and terrestrial sewage of Zhanjiang Bay (ZJB) in four different seasons were investigated. The results identified the heavy metal concentrations in the sewage outlet around ZJB had significant seasonal variation.

Characterization and seasonal variation in biofilms attached to leaves of submerged plant.

The microorganisms and functional predictions of leaf biofilms on submerged plants (Vallisneria natans (Val)) and in water samples (surface water (S) and bottom water (B)) in different seasons were evaluated in this study. S and B groups had 3249 identical operational taxonomic units (OTUs) (50.03%), while the Val group only had 1201 (18.

Temporal variations in reactive oxygen species in biofilms of submerged macrophytes: The key role of microbial metabolism mediated by oxygen fluctuations.

Reactive oxygen species (ROS) play a crucial role in the biogeochemistry of aquatic environments, yet their occurrence and accumulation in the biofilm of submerged macrophytes have been poorly documented. Herein, we first investigated the light-dark cycling fluctuations of biofilm microenvironment and the temporal variations of a representative ROS (O) during biofilm succession on the macrophyte leaves and subsequently quantified the photochemical processes in biofilms. The sustained production of O exhibited a distinct rhythmic fluctuation from 32.

Photobleaching-induced changes in the optical and photochemical properties of algal organic matter.

Algal organic matter (AOM), a significant source of endogenous dissolved organic matter (DOM) is released in high concentrations during cyanobacterial blooms, along with cyanotoxins. Subsequent photobleaching of AOM is an important phenomenon to investigate. In this study, intracellular organic matter (IOM) and extracellular organic matter (EOM) were extracted from cultured cyanobacteria taken from Taihu Lake in China.

Purification of aquaculture wastewater by macrophytes and biofilm systems: Efficient removal of trace antibiotics and enrichment of antibiotic resistance genes.

The purification performance of aquaculture wastewater and the risk of antibiotic resistance genes (ARGs) dissemination in wetlands dominated by macrophytes remain unclear. Here, the purification effects of different macrophytes and biofilm systems on real aquaculture wastewater were investigated, as well as the distribution and abundance of ARGs. Compared to the submerged macrophytes, artificial macrophytes exhibited higher removal rates of TOC (58.

Seasonal variation, spatial distribution, and sources of PAHs in surface seawater from Zhanjiang bay influenced by land-based inputs.

This study was carried out for a comprehensive understanding of the concentrations, seasonal variation, spatial distribution, sources, and land-based inputs of polycyclic aromatic hydrocarbons (PAHs) in surface seawater from Zhanjiang Bay (ZJB). Although the PAHs were ubiquitous, their concentrations were relatively low, and significant seasonal trends and spatial distributions were observed. Based on the diagnostic ratios and composition profiles, the PAHs found in this study mainly originated from coal/biomass burning, and petroleum and its combustion played an important role in the wet seasons.

Effect of different size microplastic particles on the construction of algal-bacterial biofilms and microbial communities.

Algal-bacterial symbiotic system is a biological purification system that combines sewage treatment with resource utilization and has the dual effects of carbon sequestration and pollution reduction. In this study, an immobilized algal-bacterial biofilm system was constructed for the treatment of natural sewage. Effects of exposure to microplastics (MPs) with different particle diameters (0.

Phosphorus speciation and sedimentary phosphorus release in an urban bay (Dachan Bay, China) impacted by multiple anthropogenic perturbations.

Sedimentary phosphorus (P) release and retention are important in controlling P dynamics in coastal waters. Here, two sediment cores were analysed to understand the P speciation and sedimentary P release characteristics in Dachan Bay, Shenzhen, where was highly influenced by human activity. Total phosphorus (TP) concentrations, 52.

Seasonal changes driving shifts of aquatic rhizosphere microbial community structure and the functional properties.

Ecological floating beds could enable roots to become suspended and this allowed submerged roots to harbour various types of microbes. But, there was a lack of systematic research on microbial community structure changes and the influencing mechanisms. In this study, the ecological floating beds were constructed using selected plants [Cyperus involucratus Rottboll (Cyp), Thalia dealbata Fraser (Tha) and Iris tectorum Maxim (Iri)] that was compared with a control group [static water (S)].

The binding effect and photooxidation on oxytetracycline with algal extracellular polymeric substances and natural organic matter.

Surface water contains a large amount of dissolved organic matter (DOM). Interactions between DOM and micropollutants have a significant impact on micropollutant degradation. In this study, algal extracellular polymeric substances (EPS) and natural organic matter (NOM) were selected as two DOM sources and oxytetracycline (OTC) as a representative micropollutant.

Seasonal Distribution, Composition, and Inventory of Plastic Debris on the Yugang Park Beach in Zhanjiang Bay, South China Sea.

Plastic debris contamination in marine environments is a global problem that poses a considerable threat to the sustainability and health of coastal ecosystems. Marine beaches, as the key zones where terrestrial plastic debris reach coastal waters, are faced with the increasing pressures of human activities. In this study, we explored the distribution, composition, and inventory of plastic debris over seasonal and tidal zones at the Yugang Park Beach (YPB) in Zhanjiang Bay, South China Sea, to provide a baseline for plastic debris on a marine beach.

Spatiotemporal Variation and Influencing Factors of TSP and Anions in Coastal Atmosphere of Zhanjiang City, China.

Water-soluble anions and suspended fine particles have negative impacts on ecosystems and human health, which is a current research hotspot. In this study, coastal suburb, coastal urban area, coastal tourist area, and coastal industrial area were explored to study the spatiotemporal variation and influencing factors of water-soluble anions and total suspended particles (TSP) in Zhanjiang atmosphere. In addition, on-site monitoring, laboratory testing, and analysis were used to identify the difference of each pollutant component at the sampling stations.

Effects of microplastics of different sizes on the Chlorella vulgaris - Ganoderma lucidum co-pellets formation processes.

The effects of different sized MPs on the formation process of algal-fungal co-pellets were studied. The results show that a maximum biomass recovery of 70.96% and a minimum F/F ratio of 0.

Responses of submerged plant Vallisneria natans growth and leaf biofilms to water contaminated with microplastics.

Microplastics pose a serious threat to ecological processes and environmental health. To evaluate the toxic effects of the exposure of microplastics on submerged plants and biofilms, eel grass (Vallisneria natans) was exposed to different concentrations of microplastics (10-50 mg L). The changes in microbial community on leaf biofilms were also tested.

Relationship of Anxiety and Depression with Perfectionism in Patients with Aesthetic All-Ceramic Repair of Anterior Teeth.

BACKGROUND Many psychological problems arising from patients undergoing aesthetic repair of teeth should be considered. However, there are no published studies on the relationship between anxiety/depression and perfectionism in patients with aesthetic repair of anterior teeth. MATERIAL AND METHODS A total of 640 patients receiving aesthetic repair of anterior teeth were assessed using the Corah dental anxiety scale (CDAS), a self-rating anxiety scale (SAS), a self-rating depression scale (SDS), and the Chinese version of the Frost Multidimensional Perfectionism Psychological Scale (CFMPS).