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Livestock manure is known to be a significant reservoir of antibiotic resistance genes (ARGs), posing a major threat to human health and animal safety. ARGs are found in both intracellular and extracellular DNA fractions. However, there has been no comprehensive analysis of these fractions in commercial organic fertilizers (COFs). The present study conducted a systematic survey of the profiles of intracellular ARGs (iARGs) and extracellular ARGs (eARGs) and their contributing factor in COFs in Northern China. Results showed that the ARG diversity in COFs (i.e., 57 iARGs and 53 eARGs) was significantly lower than that in cow dung (i.e., 68 iARGs and 69 eARGs). The total abundance of iARGs and eARGs decreased by 85.7% and 75.8%, respectively, after compost processing, and there were no significant differences between iARGs and eARGs in COFs (P > 0.05). Notably, the relative abundance of Campilobacterota decreased significantly (99.1–100.0%) after composting, while that of Actinobacteriota and Firmicutes increased by 21.1% and 29.7%, respectively, becoming the dominant bacteria in COFs. Co-occurrence analysis showed that microorganisms and mobile genetic elements (MGEs) were more closely related to eARGs than iARGs in COFs. And structural equation models (SEMs) further verified that microbial community was an essential factor regulating iARGs and eARGs variation in COFs, with a direct influence (λ = 0.74 and 0.62, P < 0.01), following by similar effects of MGEs (λ = 0.59 and 0.43, P < 0.05). These findings indicate the need to separate eARGs and iARGs when assessing the risk of dissemination and during removal management in the environment. [Display omitted] • The study explored the profiles of eARGs and iARGs in commercial organic fertilizers. • There was no significant difference between iARGs and eARGs in COFs. • MGEs played a key role in structuring ARGs in COFs under different bacterial contexts. • Microorganism, eMGEs and eARGs had stronger correlation than that of intracellular ones. [ABSTRACT FROM AUTHOR]

Doctors' prescribing behaviors impact both medical expenses and health resources. This study aims to identify the significant determinants of prescribing behaviors of doctors, which could potentially provide theoretical evidence on how to improve prescribing decisions. A multistage, stratified, cluster, random sampling method was employed in this survey. Data were collected from Jiangsu and Shanxi provinces in China in 2018. A total of 444 doctors in public hospitals completed the self‐administered questionnaires. A structural equation model based on the theory of planned behavior (TPB) was adopted for analysis. On the basis of the TPB, we constructed a model of doctors' prescribing behaviors, which explained the subjective and objective reasons for irrational prescribing behavior. Behavioral attitude, subjective norms, and perceived behavioral control could positively influence the actual behaviors, of which subjective norms impact prescribing behaviors the most. Employing the TPB helped in identifying determinants of prescribing behaviors from a new perspective. More significant policy changes and government support are required to help improve appropriate prescribing behaviors and ultimately make better prescribing decisions. This study provided a deeper understanding of this complex issue and will inform the development of a theory and evidence‐based intervention for future research. [ABSTRACT FROM AUTHOR]

[Display omitted] • Actinomycetes increased the degradation rate of straw compost by nearly 15%. • Actinomycetes promoted the transformation from fulvic acid to humic acid. • Actinomycetes reshape the compositional features of humic acid. • Structural distribution of humic acid is a key factor affecting humification. This study aimed to explore the mechanism of actinomycetes inoculation to promote humification based on spectroscopy during straw waste composting. Results showed that inoculating actinomycetes could significantly increase the humification index and humification ratio, which were 2.53% and 21.79% respectively (P < 0.05). A spectroscopic analysis suggested that actinomycetes promoted the relative content of complex components of humic acid and reshaped the structural distribution of two sub fluorescence peaks in it. Furthermore, variance partitioning analysis demonstrated that compared with the intensity, the high-quality uniform distribution of fluorescence peaks had a greater contribution to the improvement of humification. In addition, structural equation model further verified that actinomycetes inoculation promoted the transformation of fulvic acid to humic acid, and then promoted the formation of humic acid. Therefore, actinomycetes inoculation can promote the humification of straw compost by reshaping the complex components of humic acid. [ABSTRACT FROM AUTHOR]

Composting process is accompanied by the emission of greenhouse gases such as nitrous oxide (N 2 O). Biochar addition effectively reduced the release of N 2 O. However, the specific impact mechanism of biochar is unclear. Therefore, the aim of this study was to reveal the response of N 2 O-related microorganisms to biochar addition during chicken manure composting. Results suggested that the addition of biochar reduced the species of N 2 O-related microorganisms from 22 to 19, and changed the functional roles. Network analysis further revealed that the addition of biochar weakened the transformation relationship between nitrification and denitrification, which effectively inhibited the denitrification rate. Ultimately, Structural equation models verified that the addition of biochar made core microorganism Ornithinibacillus prevail, which weakened the denitrification during composting. This study identified the core microorganisms that regulated the production of N 2 O during chicken manure composting, and provided a theoretical basis for the targeted regulation of N 2 O emission. [Display omitted] [ABSTRACT FROM AUTHOR]

Horizontal gene transfer of heavy metal resistance genes and antibiotic resistance genes in bacteria frequently occurred during composting. However, the relevancy between heavy metal pollution with different degrees and the occurrence of horizontal gene transfer during composting was unclear. Therefore, this study aimed to clarify the underlying relationship. The changes of resistance gene abundance and network analysis results showed that heavy metal pollution induced high level of resistance gene abundance in microorganisms and promoted the occurrence of horizontal gene transfer. Furthermore, regression fitting models indicated that the relevancy between resistance genes abundance and horizontal gene transfer under high pollution (HP: R = 0.90) was weakener than that under low pollution (LP: R = 0.95) and medium pollution (MP: R = 0.97). Ultimately, structural equation models further verified that the abundance of resistance genes was mainly caused by horizontal gene transfer during LP (coefficients: 0.997) and MP (coefficients: 0.993) composting. However, the high level of resistance gene abundance was caused by host bacteria (coefficients: 0.775) and horizontal gene transfer (coefficients: 0.701) during HP composting. The serious heavy metal pollution had selection pressure on host bacteria to induce them to develop resistance during HP composting, rather than only through horizontal gene transfer. Therefore, mild heavy metal pollution was more liable to cause horizontal gene transfer and increase the spread risk of resistance genes during composting. This study helped to better understand the risks caused by heavy metal pollution by evaluating the frequency of horizontal gene transfer at different pollution levels during composting. [Display omitted] • Heavy metal pollution induced a high level of resistance gene abundance. • Horizontal gene transfer contributed more to gene abundance under mild pollution. • Heavy metals induced selection pressure on host bacteria under serious pollution. • The gene abundance was caused by host bacteria abundance under serious pollution. • Mild metal pollution was more likely to cause spread risk of resistance genes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The key factors affecting shikimic acid (SA) pathway were identified. • The key influencing factors of each metabolite were obviously different. • Only the SA content in lawn waste could be affected by physicochemical factors. • The more complex environment, the more factors that restrict protocatechuic acid. • A new direction for improving SA metabolic intensity during composting. Metabolites of shikimic acid (SA) pathway can be used as humic substance (HS) precursors. Due to the complexity of SA anabolism, there were few studies on SA pathway during composting. The aim of this study was to identify the key drivers of SA pathway during different materials composting. During composting, the SA, protocatechuic acid (PA) and gallic acid (GA) decreased by 57.09%, 72.27% and 54.04% on average, respectively. The structural equation model showed that SA had key driving factors (organic matter and pH) during lawn waste composting. In addition, the complexity of material structure was the main factor affecting PA driving factors. The factors and degree of influence on GA varied with different materials. Accordingly, this study provided theoretical support for the improvement of SA metabolic intensity by single material and mixed material composting, and further provided a new direction for future HS research. [ABSTRACT FROM AUTHOR]

• Fenton pretreatment promoted the organic fractions degradation. • Fenton pretreatment promoted the humic substances (HS) formation. • Bacterial communities structure and diversity were changed by Fenton pretreatment. • Key environmental factors and microbes were identified. The goal of this work was to explore the effect of Fenton pretreatment combined with bacteria inoculation on the formation of humic substances (HS) during rice straw composting. In this study, the compound bacterial agents were inoculated after Fenton pretreatment during rice straw composting. The results suggested that the coupling effects of Fenton pretreatment and bacteria inoculation promoted the humification process, which might be the reason of organic fractions degradation and transformation. In addition, the bacterial communities structure and diversity were changed by Fenton pretreatment and inoculation. Key microbial genera linking to the transformation of organic fractions were determined by network analysis. Redundancy analysis and structural equation model analysis indicated that Fenton pretreatment, inoculation, amino acid, soluble sugar and beta-diversity as the key factors affecting organic fractions transformation during composting. Therefore, the combined application Fenton pretreatment with bacteria inoculation provided a new method to promote the HS amount. [ABSTRACT FROM AUTHOR]

• Fenton pretreatment changed structure changes of the raw materials. • Part of lignocellulose-degrading enzymes were enhanced by Fenton pretreatment. • Key enzymes and environmental factors have been identified by RDA and SEMs. • Lignocellulose degradation efficiency was improved by Fenton pretreatment. This study aims to explore the effect of Fenton pretreatment on organic fractions, enzymes activities and microbial communities during composting. In this study, rice straw was chosen to be composted after pretreatment. The results indicated that Fenton pretreatment significantly increased the degradation of organic matter and coarse fiber contents, which might be the reason that Fenton pretreatment enhanced lignocellulose-degrading enzymes activities during composting, including CMCase, FPase, xylanase, manganese peroxidase, lignin peroxidase and laccase. Additionally, Fenton pretreatment reshaped bacteria community. The key enzymes and environmental factors, which affected organic fractions degradation were identified by redundancy analysis. Furthermore, structural equation modeling and variation partitioning analysis further revealed possible mechanisms of organic fractions degradation in different treatments during composting. In summary, the combined application Fenton pretreatment and composting improved lignocellulose degradation efficiency, which provided for an effective and environment-friendly way to manage lignocellulose wastes. [ABSTRACT FROM AUTHOR]

• A novel method to remove heavy metals from composting system. • Sponge and cotton have good ability to remove heavy metals. • Significant movement of heavy metals from outside to adsorbent column was observed. • Functional bacteria have a direct and indirect affect to the heavy metals removal. The aim of this study was to remove heavy metals from composting system using a novel method combined functional bacteria with adsorbent materials. Four types of adsorbent materials were selected in this study. Results showed that Cr had significant removal efficiency, especially in sponge treatment (19.09%) and cotton treatment (26.36%). In addition, a significant movement of heavy metals from the outside to adsorbent column was also observed. RDA results indicated that bands 1, 2, 10, 18, 19 and 20 had negative correlations with six types of heavy metals, which contributed to the removal of heavy metals. Structural equation models further confirmed functional bacteria can directly affect the removal of Cu, Cd and Cr. In addition, it can also indirectly remove Pb and Cr by changing native bacteria. In summary, this study suggested the combination of functional bacteria and adsorbent materials was effective to remove heavy metals from composting system. [ABSTRACT FROM AUTHOR]