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Apple replant disease (ARD) negatively affects plant growth and reduces yields in replanted orchards. In this study, biochar and humic acid were applied to apple replant soil. We aimed to investigate whether biochar and humic acid could promote plant growth and alleviate apple replant disease by reducing the growth of harmful soil microorganisms, changing soil microbial community structure, and improving the soil environment. This experiment included five treatments: apple replant soil (CK), apple replant soil with methyl bromide fumigation (FM), replant soil with biochar addition (2 %), replant soil with humic acid addition (1.5 ‰), and replant soil with biochar combined with humic acid. Seedling biomass, the activity of antioxidant enzymes in the leaves and roots, and soil environmental variables were measured. Microbial community composition and structure were analyzed using ITS gene sequencing. Biochar and humic acid significantly reduced the abundance of Fusarium and promoted the recovery of replant soil microbial communities. Biochar and humic acid also increased the soil enzymes activity (urease, invertase, neutral phosphatase, and catalase), the plant height, fresh weight, dry weight, the activity of antioxidant enzymes (superoxide dismutase, peroxidase, and catalase), and root indexes of apple seedlings increased in replant soil. In sum, We can use biochar combined with humic acid to alleviate apple replant disease. • Biochar and humic acid could reduce Fusarium which causes the apple replant disease (ARD). • T application obviously increased soil microbial diversity and richness, and regulated fungal community structure in replant soil. • The addition of biochar and humic acid significantly increased the apple seedlings growth and alleviate the ARD. [ABSTRACT FROM AUTHOR]

Amidst the global antimicrobial resistance (AMR) crisis, antibiotic resistance has permeated even the most remote environments. To understand the dissemination and evolution of AMR in minimally impacted ecosystems, the resistome and mobilome of wetlands across the Qinghai-Tibetan Plateau and its marginal regions were scrutinized using metagenomic sequencing techniques. The composition of wetland microbiomes exhibits significant variability, with dominant phyla including Proteobacteria, Actinobacteria, Bacteroidetes, and Verrucomicrobia. Notably, a substantial abundance of Antibiotic Resistance Genes (ARGs) and Mobile Genetic Elements (MGEs) was detected, encompassing 17 ARG types, 132 ARG subtypes, and 5 types of MGEs (Insertion Sequences, Insertions Sequences, Genomic Islands, Transposons, and Integrative Conjugative Elements). No significant variance was observed in the prevalence of resistome and mobilome across different wetland types (i.e., the Yellow River, other rivers, lakes, and marshes) (R =-0.5882, P =0.607). The co-occurrence of 74 ARG subtypes and 22 MGEs was identified, underscoring the pivotal role of MGEs in shaping ARG pools within the Qinghai-Tibetan Plateau wetlands. Metagenomic binning and analysis of assembled genomes (MAGs) revealed that 93 out of 206 MAGs harbored ARGs (45.15 %). Predominantly, Burkholderiales, Pseudomonadales, and Enterobacterales were identified as the primary hosts of these ARGs, many of which represent novel species. Notably, a substantial proportion of ARG-carrying MAGs also contained MGEs, reaffirming the significance of MGEs in AMR dissemination. Furthermore, utilizing the arg_ranker framework for risk assessment unveiled severe contamination of high-risk ARGs across most plateau wetlands. Moreover, some prevalent human pathogens were identified as potential hosts for these high-risk ARGs, posing substantial transmission risks. This study aims to investigate the prevalence of resistome and mobilome in wetlands, along with evaluating the risk posed by high-risk ARGs. Such insights are crucial for informing environmental protection strategies and facilitating the management of water resources on the Qinghai-Tibetan Plateau. [Display omitted] • Consistent resistome and mobilome prevalence observed in various wetlands types. • Human activities may drive pathogens emergence and ARGs distribution shifts. • High-risk ARGs pollution predominated in most Qinghai-Tibetan Plateau wetlands. [ABSTRACT FROM AUTHOR]

Jilin ginseng, Panax ginseng , is a valuable medicinal herb whose ginsenosides are its major bioactive components. The ginseng oxidosqualene cyclase (PgOSC) gene family is known to play important roles in ginsenoside biosynthesis, but few members of the gene family have been functionally studied. The PgOSC gene family has been studied by an integrated analysis of gene expression-ginsenoside content correlation, gene mutation-ginsenoside content association and gene co-expression network, followed by functional analysis through gene regulation. We found that five of the genes in the PgOSC gene family, including two published ginsenoside biosynthesis genes and three new genes, were involved in ginsenoside biosynthesis. Not only were the expressions of these genes significantly correlated with ginsenoside contents, but also their nucleotide mutations significantly influenced ginsenoside contents. These results were further verified by regulation analysis of the genes by methyl jasmonate (MeJA) in ginseng hairy roots. Four of these five PgOSC genes were mapped to the ginsenoside biosynthesis pathway. These PgOSC genes expressed differently across tissues, but relatively consistent across developmental stages. These PgOSC genes formed a single co-expression network with those published ginsenoside biosynthesis genes, further confirming their roles in ginsenoside biosynthesis. When the network varied, ginsenoside biosynthesis was significantly influenced, thus revealing the molecular mechanism of ginsenoside biosynthesis. At least five of the PgOSC genes, including the three newly identified and two published PgOSC genes, are involved in ginsenoside biosynthesis. These results provide gene resources and knowledge essential for enhanced research and applications of ginsenoside biosynthesis in ginseng. • Three new PgOSC genes involved in ginseng ginsenoside biosynthesis were identified. • Analyses of gene expression, mutation and network identify strong candidate genes. • Genes involved in ginsenoside biosynthesis are interacted in a form of network. • Variation of the gene network interactions greatly affects ginsenoside biosynthesis. [ABSTRACT FROM AUTHOR]

Zwitterionic surface has been proven to be a good candidate for improving hemocompatible and antibiofouling properties. However, it can only passively repel the adsorption of microbes and is unable to kill the adherent or trapped microbes. The purpose of our study is to develop a facile method based on synergy “repel and kill” strategy and prepare dual antifouling and antibacterial surface. Herein, the poly(2-(dimethylamino) ethyl methacrylate) (PDMAEMA) was first constructed via surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (ARGET-ATRP) method, followed by partial quaternization in order to form polycarboxybetaine and polysulfobetaine. The conversion rates of PDMAEMA to polyzwitterions were evaluated by X-ray photoelectron spectroscopy analysis (XPS). Surface characterizations by ATR-FTIR, XPS, and AFM demonstrated that zwitterionic polymer brushes were successfully grafted. The remained PDMAEMA(weak cationic) and formed zwitterions(neutral) endowed the surface with the synergetic antibacterial and antifouling properties. The resulting PET sheets showed outstanding antifouling property featured by the reduced adhesion of 3T3 fibroblast cells and E. coli . Additionally, these sheets displayed excellent hemocompatibility such as non-cytotoxicity, repelled protein adsorption, reduced platelet adhesion, and prolonged blood blotting time. These synergistic surfaces with neutral zwitterions and weak cations are promising for biomedical applications. [ABSTRACT FROM AUTHOR]

Perennial tree soil inhibits the growth of replanting apples, but the mechanism that underlies this inhibition is poorly understood. A total of 57 perennial tree soils were selected for the collection of soil samples in the Bohai Bay in May 2018. The severity of apple replant disease (ARD) for each soil was determined by calculating the rate of inhibition of growth replanted apple trees. A high-throughput sequencing analysis of internal transcribed spacer (ITS) was used to determine the soil fungal community. A correlation analysis was used to determine the relationship between the rate of inhibition of apple growth and soil factors. The degree of inhibition of plant growth varied substantially among the 57 soil samples examined. Different perennial tree soils have varying degrees of ARD. There was no significant difference in the composition of fungal community at the phylum level, but the genus level differed substantially. The abundances of Fusarium and Mortierella species and the contents of phloridin in the soil and soil organic matter (SOM) were significantly correlated with ARD severity. Structural equation modeling also emphasized that the degree of occurrence of ARD was directly or indirectly affected by Fusarium , Mortierella , phloridin and SOM. A correlation analysis can only be used as an indicator, and further research is merited to reveal how soil parameters affect ARD. [Display omitted] • The degree of apple replant disease varied in different orchards. • The Mortierella and soil organic matter were significantly negatively correlated with apple replant disease. • The Fusarium and phloridzin in the soil significantly positively correlated with apple replant disease. • There were no correlation between HN, AP, AK, pH and apple replant disease. [ABSTRACT FROM AUTHOR]

Abstract: We report a facile and effective strategy for synthesizing morphology-controlled patterned ZnO nanostructures. Polymeric nanowell arrays were employed as scaffold templates, followed by solution dipping and calcination process, polygonal ZnO nanobowl structures were fabricated on silicon substrate. The ordered polymeric nanowell arrays not only provided confined areas for depositing desired materials, but also induced shape transition of ZnO nanobowls from circular to polygonal. The morphology of the patterned ZnO nanostructures can be easily controlled by tuning parameters of polymeric nanowell arrays and other treatment conditions. The patterned structures were characterized by field emission scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). [Copyright &y& Elsevier]

Abstract: To elucidate the host transcriptional response to Salmonella enterica serovar Typhimurium, Affymetrix porcine GeneChip analysis of pig mesenteric lymph nodes was used to identify 848 genes showing differential expression across different times after inoculation or when compared to non-inoculated controls. Annotation analyses showed that a high proportion of these differentially expressed (DE) genes are involved in immune and inflammatory responses. T helper 1, innate/inflammatory, and antigen-processing pathways were induced at 24 h post-inoculation (hpi) and/or 48 hpi, while apoptosis and antigen presentation/dendritic cell function pathways were downregulated at 8 hpi. Cluster analyses revealed that most DE genes annotated as NFκB targets were grouped into a specific induced subcluster, while many translation-related DE genes were found in a repressed subcluster. Quantitative polymerase chain reaction analyses confirmed the Affymetrix results, revealing transcriptional induction of NFκB target genes at 24 hpi and suppression of the NFκB pathway from 24 to 48 hpi. We propose that such NFκB suppression in antigen-presenting cells may be the mechanism by which S. Typhimurium eludes a strong inflammatory response to establish a carrier status in pigs. [Copyright &y& Elsevier]

The photoelectrochemical (PEC) performance of ZnO is restricted by its low light absorption ability and high recombination rate of photogenerated carriers. In order to overcome these drawbacks, ZnO/CdS/CdSe heterostructures are prepared on Zn foil substrate using facile three-step methods containing hydrothermal growth, successive ionic layer adsorption reaction (SILAR) and modified chemical bath deposition (CBD). The effects of process parameters containing the number of SILAR cycles of CdS, sensitization sequence of CdS and CdSe, and precursors of CdSe on PEC performance of ZnO/CdS/CdSe heterostructures, and ZnO NRAs on PEC performance of CdS/CdSe co-sensitizer have been scrutinized. Through CdS and CdSe co-sensitization, a layer of CdS/CdSe nanofilm is conformally deposited on ZnO nanorod arrays (NRAs) observed by transmission electron microscopy (TEM). Both the visible-light absorption ability and separation efficiency of photogenerated carriers of ZnO NRAs are significantly enhanced evidenced by UV–vis diffuse reflectance absorption spectra, photoluminescence (PL) spectra and electrochemical impedance spectra. Due to the synergistic effect of ZnO NRAs and CdS/CdSe co-sensitizer, the ZnO/CdS/CdSe heterostructures with five SILAR cycles and one modified CBD cycle (ZnO-CdS5-CdSe) show efficient PEC properties with photocurrent density of 6.244 mA/cm2 at −0.2 V vs Ag/AgCl under light illumination of 100 mW/cm2, which are 57.28 and 4.73 times higher than those of pristine ZnO NRAs and CdS/CdSe clusters, respectively. Moreover, the photoconversion efficiency and incident photon to current conversion efficiency (IPCE) of the ZnO-CdS5-CdSe photoanode reach 4.381% and 80.92%, respectively. The heterostructures based on Zn foil substrate in this study can be a promising candidate for practical PEC application and other applications such as photocatalytic degradation and solar cell due to its low manufacturing cost, large-scale production and efficient PEC ability. [ABSTRACT FROM AUTHOR]

The integration of multiscale micro- and macroenvironment has been demonstrated as a critical role in designing biomimetic scaffolds for peripheral nerve tissue regeneration. While it remains a remarkable challenge for developing a biomimetic multiscale scaffold for enhancing 3D neuronal maturation and outgrowth. Herein, we present a 3D bioprinted multiscale scaffold based on a modular bioink for integrating the 3D micro- and macroenvironment of native nerve tissue. Gelatin methacryloyl (GelMA)/Chitosan Microspheres (GC-MSs) were prepared by a microfluidic approach, and the effect of these microspheres on enhancing neurite outgrowth and elongation of PC12 cells was demonstrated. The 3D multiscale composite scaffolds were bioprinted based on microspheres and hydrogel as the modular bioink. The co-culture of PC12 cells and RSC96 Schwann cells within these 3D biomimetic scaffolds were investigated to evaluate such a 3D multiscale environment for neurite outgrowth and Schwann cell proliferation. These results indicate that such multiscale composite scaffold with hydrogel microspheres provided a suitable 3D microenvironment for enhancing neurite growth, and the 3D printed hydrogel network provided a 3D macroenvironment mimicking the epineurium layer for Schwann cells proliferation and nerve cell organization, which is promising for the great potential applications in nerve tissue engineering. [ABSTRACT FROM AUTHOR]

Abstract: High-quality and stable PS@TiO2 core–shell microsphere colloidal crystals were prepared by electrostatic colloid stabilization combined with two-substrate vertical deposition method. The polyelectrolyte stabilized colloids self-assembled into face-centered cubic arrays with the (111) face perpendicular to the substrate. These colloidal crystals are gifted with high mechanical stability toward the flow of solution. Structure-property correlations were made using scanning electron microscopy and UV–vis–NIR spectroscopy. Optical spectra showed the presence of an L-stopband peak in the photonic band structure. Besides, these PS@TiO2 colloidal crystals can be used as templates to fabricate the nonspherical macro-porous materials, and complete band gaps can be more easily obtained from such structure than from their spherical counterparts due to their lower symmetries. This work will hold the promise of enhanced photonic band gap materials. [Copyright &y& Elsevier]