[Changes in diversity of marsh plant communities under shrub encroachment in Sanjiang Plain and their soil control factors].

In this study, we explored the changes in plant community diversity and their relationship with soil factors under shrub encroachment pressure by selecting four marsh areas in Sanjiang Plain with different degrees of shrub cover (, 0≤≤100%), including marsh with no shrub encroachment (=0), light shrub encroachment (0<≤30%), medium shrub encroachment (30%<≤70%), and heavy shrub encroachment (70%<≤100%). The results showed that shrub encroachment was the main reason for the heterogeneity of plant community composition in marsh. With shrub encroachment, the dominant species was replaced by , whereas disappeared.

Research on Chemical Mechanical Polishing Technology for Zirconium-Based Amorphous Alloys.

Crystallization often occurs in the processing of amorphous alloys, causing the materials lose their excellent properties. The study adopts chemical mechanical polishing of amorphous alloys, presenting the effect of the rotational speed of the polishing turntable, size of abrasive, polishing pressure, and oxidant concentration. The Taguchi method is used to find the best processing parameters, and AFM is used to characterize the machined material surface.

Estimating unconfirmed COVID-19 infection cases and multiple waves of pandemic progression with consideration of testing capacity and non-pharmaceutical interventions: A dynamic spreading model.

The novel coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has unique epidemiological characteristics that include presymptomatic and asymptomatic infections, resulting in a large proportion of infected cases being unconfirmed, including patients with clinical symptoms who have not been identified by screening. These unconfirmed infected individuals move and spread the virus freely, presenting difficult challenges to the control of the pandemic. To reveal the actual pandemic situation in a given region, a simple dynamic susceptible-unconfirmed-confirmed-removed (D-SUCR) model is developed taking into account the influence of unconfirmed cases, the testing capacity, the multiple waves of the pandemic, and the use of non-pharmaceutical interventions.

Aerobic composting of chicken manure with penicillin G: Community classification and quorum sensing mediating its contribution to humification.

Chicken manure containing antibiotics is a hazardous biological waste. The purpose of our study was to investigate how different concentrations of penicillin G alter the bacterial community to affect humification during aerobic composting of chicken manure. The effect of quorum sensing on the bacterial community was also evaluated.

Driving factors of nitrogen conversion during chicken manure aerobic composting under penicillin G residue: Quorum sensing and its signaling molecules.

This study explored effects of different concentrations of penicillin G on nitrogen conversion, bacterial community composition, and quorum sensing during chicken manure aerobic composting. After composting, adding penicillin G down-regulated the abundance of 71 genera and up-regulated the abundance of 103 genera. These bacterial genera were mainly Firmicutes and Proteobacteria.

Intraspecific and interspecific quorum sensing of bacterial community affects the fate of antibiotic resistance genes during chicken manure composting under penicillin G stress.

In this study, the effects of penicillin G (PENG) on the fate of bacterial communities and β-lactamase antibiotic resistance genes (ARGs) during chicken manure composting were assessed, to illustrate the roles of PENG in ARGs behavior. The results showed that the total absolute abundances of 9 ARGs and 4 mobile genetic elements (MGEs) was significantly increased by PENG (P < 0.05).

Links between microbial compositions and metabolites during aerobic composting under amoxicillin stress was evaluated by 16S rRNA sequencing and gas chromatography-mass spectrometry: Benefit for the plant growth.

The purpose of this study was to identify the relationship between core bacteria and metabolites during aerobic composting and analyze the effects of metabolites on plant growth. The results revealed that amoxicillin might affect the generation and transformation of metabolites by reconstructs the bacterial communities. The peak area ratios (PAR) of esters and fatty acids (FAs) were increased, while sterols decreased during composting.

Evaluation of humic acid conversion during composting under amoxicillin stress: Emphasizes the driving role of core microbial communities.

This study aimed to investigate the effects of various amoxicillin (AMX) concentrations on humic acid (HA) formation and the bacterial community structure (BCS) during chicken manure aerobic composting. The findings showed that AMX caused a rise in pH and a shortening of the thermophilic cycle during the thermophilic period. Moreover, a high concentration of AMX (150 mg/kg) inhibited community succession and humification at maturity.

Evaluation of nitrogen conversion pathway during composting under amoxicillin stress: Mainly driven by core microbial community.

The aim of this study was to explore the effects of different concentrations of amoxicillin (AMX) on nitrogen (N) conversion and bacterial community structure during aerobic composting. The results revealed that AMX led to a lower temperature and increased pH during the thermophilic phase of composting. AMX inhibited the relative abundance (RA) of Firmicutes at the initial phase but increased the RA of Actinobacteria and Bacteroidetes compared with the control treatment.