The prevention effect of Limosilactobacillus reuteri on acute kidney injury by regulating gut microbiota.

Acute kidney injury (AKI) has considerably high morbidity and mortality but we do not have proper treatment for it. There is an urgent need to develop new prevention or treatment methods. Gut microbiota has a close connection with renal diseases and has become the new therapy target for AKI. In this study, we found the oral administration of the probiotic Limosilactobacillus reuteri had a prevention effect on the AKI induced by lipopolysaccharide (LPS). It reduced serum concentration of creatinine and urea nitrogen and protected the renal cells from necrosis and apoptosis. Meanwhile, L. reuteri improved the gut barrier function, which is destroyed in AKI, and modulated the gut microbiota and relevant metabolites. Compared with the LPS group, L. reuteri increased the proportion of Proteobacteria and reduced the proportion of Firmicutes, changing the overall structure of the gut microbiota. It also influenced the fecal metabolites and changed the metabolite pathways, such as tyrosine metabolism, pentose and glucuronate interconversions, galactose metabolism, purine metabolism, and insulin resistance. These results showed that L. reuteri is a potential therapy for AKI as it helps in sustaining the gut barrier integrity and modulating gut microbiota and related metabolites.

Responses of Zooplankton Community Pattern to Environmental Factors along the Salinity Gradient in a Seagoing River in Tianjin, China.

As the primary consumers in aquatic organisms, zooplankton play an important role in aquatic ecosystems. It is valuable for management and researchers to have an insight into the responses of zooplankton community patterns to environmental factors. In this study, RDA and variation partitioning analysis were adopted to determine the important environmental factors affecting zooplankton abundance and biomass, as well as the relative importance of different environmental factors. The findings reveal that TN (total nitrogen), WD (water depth), pH, and SAL (salinity) were all important abiotic factors shaping the zooplankton community pattern in the study area. TN affected protozoa by influencing Stentor amethystinus, while the effects of WD on copepods may have been mainly induced by the responses of Calanus sinicus and Paracyclopina nana. By inhibiting Stentor amethystinus and Vorticella lutea, pH significantly affected protozoa. In addition, Rotifera and copepods were affected by SAL mainly through the responses of Brachionus calyciflorus, Calanus sinicus, and Ectocyclops phaleratus. Importantly, fundamental alternations in the variation trends of zooplankton abundance and biomass along the salinity gradient were found when the salinity was approximately 4-5. By combining these results with the findings on phytoplankton responses to salinity in previous studies, it can be concluded that salinity may influence the river ecosystem by influencing zooplankton abundance and biomass rather than phytoplankton.

TRIM3 attenuates cytokine storm caused by Dabie bandavirus via promoting Toll-like receptor 3 degradation.

Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that was caused by the Dabie bandavirus (DBV), and it has become a global public health threat. Cytokine storm is considered to be an important pathogenesis of critical SFTS. Tripartite motif-containing 3 (TRIM3), as a member of the TRIM protein family, may contribute to the regulation of the immune and inflammatory responses after viral infection. However, whether TRIM3 plays a major role in the pathogenesis of SFTS has not yet been investigated. Methods: TRIM3 mRNA levels were detected in PBMCs between 29 SFTS patients and 29 healthy controls by qRT-PCR. We established the pathogenic IFNAR-/- SFTS mouse model successfully by inoculating subcutaneously with DBV and testing the expression levels of TRIM3 mRNA and protein by qRT-PCR and immunofluorescence in the livers, spleens, lungs, and kidneys. TRIM3OE THP-1 cells and peritoneal macrophages extracted from TRIM3-/- mice were infected with DBV. The effect of TRIM3 on cytokines was detected by qRT-PCR and ELISA. Then we examined Toll-like receptor 3 (TLR3) and protein phosphorylation in the MAPK pathway after DBV infection using Western blot. Flow cytometry was used to verify TLR3 expression on peripheral blood monocytes in SFTS patients. We further explored the interaction between TRIM3 and TLR3 using CO-IP and Western blot. Results: Compared to healthy controls, TRIM3 mRNA expression in PBMCs is decreased in SFTS patients, especially in severe cases. TRIM3 mRNA and protein were synchronously reduced in the livers, spleens, lungs, and kidney tissues of the IFNAR-/- SFTS mice model. In the DBV-infected cell model, TRIM3 overexpression can inhibit the DBV-induced release of IL-1ß, IL-6, and TNF-α, the expression of TLR3, and protein phosphorylation in the MAPK pathway, which plays an anti-inflammatory role, while TRIM3 deficiency exacerbates the pro-inflammatory effects. We further found that TRIM3 can promote TLR3 degradation through K48-linked ubiquitination. Conclusion: TRIM3 can inhibit the production of cytokines by regulating the degradation of TLR3 through K48-linked ubiquitination, which can be a therapeutic target for improving the prognosis of SFTS.

Epidemiological and Molecular Characteristics of bla NDM-1 and bla KPC-2 Co-Occurrence Carbapenem-Resistant Klebsiella pneumoniae.

Objective: Carbapenem-resistant Klebsiella pneumoniae (CRKP) has emerged and spread worldwide. It can usually cause a serious threat complicating treatment options in clinical settings. However, treatment options are limited. The present study investigates the prevalence and genetic characteristics of bla NDM-1 and bla KPC-2 co-harboring clinical isolates of Klebsiella pneumoniae. Methods: In this study, Multiplex polymerase chain reaction (PCR) was performed to detect the carbapenem-resistant genes, and the broth microdilution method was used to determine the minimum inhibitory concentrations (MICs) of antibacterial drugs. The transferability of carbapenem-resistant phenotypes was examined using filter mating assays. Overall, we used Illumina sequencing to evaluate the epidemiological and molecular characteristics of bla NDM-1 and bla KPC-2 (genes encoding carbapenemase) co-occurrence in CRKP strains. Results: All strains exhibited resistance to carbapenems and other antibiotics. However, they were still susceptible to polymyxin E. Among them, 18 isolates were positive for bla KPC-2, bla NDM-1, and multiple virulence determinants, such as genes encoding the virulence factor aerobactin, yersiniabactin, and the regulator of the mucoid phenotype (rmpA and rmpA2). Whole genome sequencing revealed that the 18 CRKP strains belonged to ST11 and capsular serotype KL64, and could be grouped into two evolutionary branches. Furthermore, these strains displayed hypervirulence potential since all of them carried pLVPK-like plasmid. Conclusion: These findings suggested that ST11-KL64 CRKP strains are major threats in terms of nosocomial infections in this hospital. Hence, new strategies should be urgently developed to monitor, diagnose, and treat this high-risk CRKP clone.

Retracted and Republished from: "Gut Microbiota Mediates the Therapeutic Effect of Monoclonal Anti-TLR4 Antibody on Acetaminophen-Induced Acute Liver Injury in Mice".

Acetaminophen (APAP) overdose is one of the most common causes of acute liver injury (ALI) in Western countries. Many studies have shown that the gut microbiota plays an important role in liver injury. Currently, the only approved treatment for APAP-induced ALI is N-acetylcysteine; therefore, it is essential to develop new therapeutic agents and explore the underlying mechanisms. We developed a novel monoclonal anti-Toll-like receptor 4 (TLR4) antibody (ATAB) and hypothesized that it has therapeutic effects on APAP-induced ALI and that the gut microbiota may be involved in the underlying mechanism of ATAB treatment. Male C57BL/6 mice were treated with APAP and ATAB, which produced a therapeutic effect on ALI and altered the members of the gut microbiota and their metabolic pathways, such as Roseburia, Lactobacillus, Akkermansia, and the fatty acid pathway, etc. Furthermore, we verified that purified short-chain fatty acids (SCFAs) could alleviate ALI. Moreover, a separate group of mice that received feces from the ATAB group showed less severe liver injury than mice that received feces from the APAP group. ATAB therapy also improved gut barrier functions in mice and reduced the expression of the protein zonulin. Our results revealed that the gut microbiota plays an important role in the therapeutic effect of ATAB on APAP-induced ALI. IMPORTANCE In this study, we found that a monoclonal anti-Toll-like receptor 4 antibody can alleviate APAP-induced acute liver injury through changes in the gut microbiota, metabolic pathways, and gut barrier function. This work suggested that the gut microbiota can be a therapeutic target of APAP-induced acute liver injury, and we performed foundation for further research.

Dual-branch collaborative learning network for crop disease identification.

Crop diseases seriously affect the quality, yield, and food security of crops. redBesides, traditional manual monitoring methods can no longer meet intelligent agriculture's efficiency and accuracy requirements. Recently, deep learning methods have been rapidly developed in computer vision. To cope with these issues, we propose a dual-branch collaborative learning network for crop disease identification, called DBCLNet. Concretely, we propose a dual-branch collaborative module using convolutional kernels of different scales to extract global and local features of images, which can effectively utilize both global and local features. Meanwhile, we embed a channel attention mechanism in each branch module to refine the global and local features. Whereafter, we cascade multiple dual-branch collaborative modules to design a feature cascade module, which further learns features at more abstract levels via the multi-layer cascade design strategy. Extensive experiments on the Plant Village dataset demonstrated the best classification performance of our DBCLNet method compared to the state-of-the-art methods for the identification of 38 categories of crop diseases. Besides, the Accuracy, Precision, Recall, and F-score of our DBCLNet for the identification of 38 categories of crop diseases are 99.89%, 99.97%, 99.67%, and 99.79%, respectively. 811.

SCGNet: efficient sparsely connected group convolution network for wheat grains classification.

Introduction: Efficient and accurate varietal classification of wheat grains is crucial for maintaining varietal purity and reducing susceptibility to pests and diseases, thereby enhancing crop yield. Traditional manual and machine learning methods for wheat grain identification often suffer from inefficiencies and the use of large models. In this study, we propose a novel classification and recognition model called SCGNet, designed for rapid and efficient wheat grain classification. Methods: Specifically, our proposed model incorporates several modules that enhance information exchange and feature multiplexing between group convolutions. This mechanism enables the network to gather feature information from each subgroup of the previous layer, facilitating effective utilization of upper-layer features. Additionally, we introduce sparsity in channel connections between groups to further reduce computational complexity without compromising accuracy. Furthermore, we design a novel classification output layer based on 3-D convolution, replacing the traditional maximum pooling layer and fully connected layer in conventional convolutional neural networks (CNNs). This modification results in more efficient classification output generation. Results: We conduct extensive experiments using a curated wheat grain dataset, demonstrating the superior performance of our proposed method. Our approach achieves an impressive accuracy of 99.56%, precision of 99.59%, recall of 99.55%, and an F 1-score of 99.57%. Discussion: Notably, our method also exhibits the lowest number of Floating-Point Operations (FLOPs) and the number of parameters, making it a highly efficient solution for wheat grains classification.

Cyclophilin A causes severe fever with thrombocytopenia syndrome virus-induced cytokine storm by regulating mitogen-activated protein kinase pathway.

Introduction: Severe fever with thrombocytopenia syndrome (SFTS) has become a global threat to public health since its first report in China in 2009. However, the pathogenesis of SFTS virus (SFTSV) in humans remains unclear. Also, there are no effective therapeutics for SFTS. Cyclophilin A (CyPA) regulates protein folding and trafficking involved in various viral infectious diseases, but its role in SFTSV infection has not been elucidated. Methods: We detected plasma CyPA levels in 29 healthy subjects and 30 SFTS patients by ELISA. In THP-1 cells and normal human peripheral blood mononuclear cells (PBMCs), SFTSV-induced extracellular CyPA (eCyPA) was also detected by ELISA. In THP-1, the effects of CyPA on Mitogen-activated protein kinase (MAPK) pathway and NF-κB were determined by Western blot. We validated the interaction between CypA and CD147 by human recombinant CyPA (hrCyPA) and the CD147 inhibitor. Effects of CyPA inhibitor Cyclosporine A (CsA) on cytokines and SFTSV replication in THP-1 cells was also detected. 8-week-old Interferon-α/ß Receptor (IFNAR) knockout (IFNAR-/-) C57BL/6 mice were divided into mock group, 106TCID50 SFTSV (Untreated) group and 106TCID50 SFTSV+CsA (CsA-treated) group. The changes of body weight, animal behavior and survival time of each group were recorded. Blood samples were collected from tail vein regularly. After death, the liver, spleen, lung, kidney and brain were collected for pathological HE staining and SFTSV-NP immunohistochemical staining. Results: Compared to healthy subjects and SFTS patients in the febrile phase of the disease, plasma CyPA levels in SFTS patients at the multi-organ dysfunction (MOD) phase showed significantly elevated (P < 0.01). Extracellular CyPA activates the MAPK pathway by binding to CD147 in THP-1 infected with SFTSV. CsA inhibits the pro-inflammatory and promoting replication effects of CyPA after SFTSV infection in vitro. In vivo, CsA can prolong the survival time and delay the weight loss of SFTSV mice. CsA reduces multi-organ dysfunction in IFNAR-/- mice infected with SFTSV. Discussion: Our results indicate that CyPA is associated with SFTSV-induced cytokine storm, which can be a potential target for SFTS therapy.

Folic acid and zinc improve hyperuricemia by altering the gut microbiota of rats with high-purine diet-induced hyperuricemia.

A high-purine diet can cause hyperuricemia and destroy the microbial composition of the gut microbiota. Both folic acid and zinc significantly reduce uric acid levels and alleviate hyperuricemia. However, whether the underlying mechanisms are associated with the regulation of the gut microbiota remain unknown. To explore alterations of the gut microbiota related to folic acid and zinc treatment in rats with hyperuricemia in our study. A hyperuricemic rat model was established with a high-purine diet. The effects of folic acid and zinc on uric acid levels were evaluated. Alterations of the gut microbiota related to hyperuricemia and the treatments were evaluated by sequencing using the Illumina MiSeq system. The results demonstrated that uric acid levels dropped observably, and the activities of adenosine deaminase (ADA) and xanthine oxidase (XOD) were downregulated after folic acid or zinc intervention. 16S rRNA gene sequencing-based gut microbiota analysis revealed that folic acid and zinc enhanced the abundance of probiotic bacteria and reduced that of pathogenic bacteria, thus improving intestinal barrier function. PICRUST analysis indicated that folic acid and zinc restored gut microbiota metabolism. These findings indicate that folic acid and zinc ameliorate hyperuricemia by inhibiting uric acid biosynthesis and stimulating uric acid excretion by modulating the gut microbiota. Thus, folic acid and zinc may be new and safe therapeutic agents to improve hyperuricemia.

Gut Microbiota Mediates the Therapeutic Effect of Monoclonal Anti-TLR4 Antibody on Acetaminophen-Induced Acute Liver Injury in Mice.

Acetaminophen (APAP) overdose is one of the most common causes of acute liver injury (ALI) in Western countries. Many studies show that the gut microbiota plays an important role in liver injury. Currently, the only approved treatment for APAP-induced ALI is N-acetylcysteine; therefore, it is essential to develop new therapeutic agents and explore the underlying mechanisms. We developed a novel monoclonal anti-Toll-like receptor 4 (TLR4) antibody (ATAB) and hypothesized that it has therapeutic effects on APAP-induced ALI and that gut microbiota may be involved in the underlying mechanism of ATAB treatment. Male C57BL/6 mice were treated with APAP and ATAB, which produced a therapeutic effect on ALI and altered the gut microbiota and their metabolic pathway, such as Roseburia, Lactobacillus, Akkermansia, and the fatty acid pathway, etc. Furthermore, we verified that purified short-chain fatty acids (SCFAs) could alleviate ALI. Moreover, a separate group of mice that received feces from the ATAB group showed less severe liver injury compared with the mice receiving feces from the APAP group. ATAB therapy also improved the gut barrier functions in mice and reduced the expression of protein zonulin. Our results revealed that gut microbiota plays an important role in the therapeutic effect of ATAB on APAP-induced ALI. IMPORTANCE In this study, we found the monoclonal anti-Toll-like receptor 4 antibody can alleviate APAP-induced acute liver injury through the change of the gut microbiota, metabolic pathways, and gut barrier function. This work suggested the gut microbiota can be the therapeutic target of the APAP-induced acute liver injury, and we performed the fundamental research for further research.

Phytoplankton Community Response to Environmental Factors along a Salinity Gradient in a Seagoing River, Tianjin, China.

A river-estuary ecosystem usually features a distinct salinity gradient and a complex water environment, so it is enormously valuable to study the response mechanism of living organisms to multiple abiotic factors under salinity stress. Phytoplankton, as an important part of aquatic microorganisms, has always been of concern for its crucial place in the aquatic ecosystem. In this study, phytoplankton data and 18 abiotic factors collected from 15 stations in Duliujian River, a seagoing river, were investigated in different seasons. The results showed that the river studied was of a Cyanophyta-dominant type. Salinity (SAL) was the key control factor for phytoplankton species richness, while water temperature (WT) was critical not only for species richness, but also community diversity, and the abundance and biomass of dominant species. Apart from WT, the abundance and biomass of dominant species were also driven by total nitrogen (TN), nitrate (NO3-), pH, and water transparency (SD). Moreover, total dissolved phosphorus (TDP), pH, and chemical oxygen demand (COD) were crucial for community diversity and evenness. The bloom of dominant species positively associated with TDP led to lower diversity and evenness in autumn. In addition, when available nitrogen was limited, Pseudoanabaena sp. could obtain a competitive advantage through the N2 fixation function. Increased available nitrogen concentration could favor the abundance of Chlorella vulgaris to resist the negative effect of WT. The results show that Oscillatoria limosa could serve as an indicator of organic contamination, and nutrient-concentration control must be effective to inhibit Microcystis bloom. This could help managers to formulate conservation measures.

How the Color Fades From Malus halliana Flowers: Transcriptome Sequencing and DNA Methylation Analysis.

The flower color of many horticultural plants fades from red to white during the development stages, affecting ornamental value. We selected Malus halliana, a popular ornamental species, and analyzed the mechanisms of flower color fading using RNA sequencing. Forty-seven genes related to anthocyanin biosynthesis and two genes related to anthocyanin transport were identified; the expression of most of these genes declined dramatically with flower color fading, consistent with the change in the anthocyanin content. A number of transcription factors that might participate in anthocyanin biosynthesis were selected and analyzed. A phylogenetic tree was used to identify the key transcription factor. Using this approach, we identified MhMYB10 as directly regulating anthocyanin biosynthesis. MhMYB10 expression was strongly downregulated during flower development and was significantly positively related to the expression of anthocyanin biosynthetic genes and anthocyanin content in diverse varieties of Malus. To analyze the methylation level during flower development, the MhMYB10 promoter sequence was divided into 12 regions. The methylation levels of the R2 and R8 increased significantly as flower color faded and were inversely related to MhMYB10 expression and anthocyanin content. Therefore, we deduce that the increasing methylation activities of these two regions repressed MhMYB10 expression.

Diversity and abundance of denitrifiers during cow manure composting / Diversidad y abundancia de desnitrificadores durante el compostaje del estiércol de vaca

Diversity and abundance of the denitrifying genes nirK, nirS and nosZ were investigated in cow manure compost using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and real-time quantitative PCR (qPCR), respectively. These three genes were detected in all the stages of the composting process. Phylogenetic analysis showed that the nirK gene was closely related to Rhizobiales, Burkholderiales, the nirS gene was closely related to Pseudomonadales and Burkholderiales, and the nosZ gene was closely related to Rhodospirillales, Rhizobiales, Pseudomonadales, and Alteromonadales. qPCR results showed that the abundance of these three genes (nirK, nirS and nosZ) reached the peak value in the late thermophilic stage of composting and abundance of the nirK gene was higher than that of the nosZ gene and the nirS gene. Redundancy analysis (RDA) showed that the diversity of the nirK and nirS genes was significantly correlated with ammonium (p < 0.05), the diversity of the nosZ gene was significantly correlated with pH (p < 0.05) and the abundance of the nirK nirS and nosZ genes was significantly correlated with temperature (p< 0.05).

La diversidad y la abundancia de los genes desnitrificadores nirK, nirS, nosZ en el compost de estiércol de vaca se investigaron por medio de la reacción en cadena de la polimerasa seguida de electroforesis en gel con gradiente de desnaturalización (PCR-DGGE) y por PCR cuantitativa (qPCR) en tiempo real, respectivamente. Estos 3 genes fueron detectados durante todas las fases del compostaje. El análisis filogenético mostró estrecha relación del gen nirK con Rhizobiales y Burkholderiales, del gen nirS con Pseudomonadales y Burkholderiales y del gen nosZ con Rhodospirillales, Rhizobiales, Pseudomonadales y Alteromonadales. Los resultados de la qPCR mostraron que la abundancia de los genes nirK, nirSy nosZ alcanzó el valor máximo en la fase termofílica tardía del compostaje, y que la abundancia del gen nirK era más elevada que los de los genes nosZ y nirS. El análisis de redundancia (RDA) mostró que la diversidad de los genes nirK y nirS estaba significativamente correlacionada con la concentración de amonio (p<0,05), mientras que la del gen nosZ estaba significativamente correlacionada con el pH (p<0,05). También mostró que la abundancia de los genes nirK, nirS y nosZ estaba significativamente correlacionada con la temperatura (p<0,05).

Jarid1b promotes epidermal differentiation by mediating the repression of Ship1 and activation of the AKT/Ovol1 pathway.

OBJECTIVES: Terminally differentiated stratified squamous epithelial cells play an important role in barrier protection of the skin. The integrity of epidermal cells is maintained by tight regulation of proliferation and differentiation. The aim of this study was to investigate the role of epigenetic regulator H3K4me3 and its demethylase Jarid1b in the control of epithelial cell differentiation. MATERIALS AND METHODS: RT-qPCR, Western blotting and IHC were used to detect mRNA and protein levels. We analysed cell proliferation by CCK8 assay and cell migration by wound healing assay. ChIP was used to measure H3K4me3 enrichment. A chamber graft model was established for epidermal development. RESULTS: Our studies showed that H3K4me3 was decreased during epidermal differentiation. The H3K4me3 demethylase Jarid1b positively controlled epidermal cell differentiation in vitro and in vivo. Mechanistically, we found that Jarid1b substantially increased the expression of mesenchymal-epithelial transition (MET)-related genes, among which Ovol1 positively regulated differentiation gene expression. In addition, Ovol1 expression was repressed by PI3K-AKT pathway inhibitors and overexpression (O/E) of the PI3K-AKT pathway suppressor Ship1. Knockdown (KD) of Ship1 activated downstream PI3K-AKT pathway and enhanced Ovol1 expression in HaCaT. Importantly, we found that Jarid1b negatively regulated Ship1 expression, but not that of Pten, by directly binding to its promoter to modulate H3K4me3 enrichment. CONCLUSION: Our results identify an essential role of Jarid1b in the regulation of the Ship1/AKT/Ovol1 pathway to promote epithelial cell differentiation.

Analyses on the Temporal and Spatial Characteristics of Water Quality in a Seagoing River Using Multivariate Statistical Techniques: A Case Study in the Duliujian River, China.

In the Duliujian River, 12 water environmental parameters corresponding to 45 sampling sites were analyzed over four seasons. With a statistics test (Spearman correlation coefficient) and multivariate statistical methods, including cluster analysis (CA) and principal components analysis (PCA), the river water quality temporal and spatial patterns were analyzed to evaluate the pollution status and identify the potential pollution sources along the river. CA and PCA results on spatial scale revealed that the upstream was slightly polluted by domestic sewage, while the upper-middle reach was highly polluted due to the sewage from feed mills, furniture and pharmaceutical factories. The middle-lower reach, moderately polluted by sewage from textile, pharmaceutical, petroleum and oil refinery factories as well as fisheries and livestock activities, demonstrated the water purification role of wetland reserves. Seawater intrusion caused serious water pollution in the estuary. Through temporal CA, the four seasons were grouped into three clusters consistent with the hydrological mean, high and low flow periods. The temporal PCA results suggested that nutrient control was the primary task in mean flow period and the monitoring of effluents from feed mills, petrochemical and pharmaceutical factories is more important in the high flow period, while the wastewater from domestic and livestock should be monitored carefully in low flow periods. The results may provide some guidance or inspiration for environmental management.

Diversity and abundance of denitrifiers during cow manure composting.

Diversity and abundance of the denitrifying genes nirK, nirS and nosZ were investigated in cow manure compost using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and real-time quantitative PCR (qPCR), respectively. These three genes were detected in all the stages of the composting process. Phylogenetic analysis showed that the nirK gene was closely related to Rhizobiales, Burkholderiales, the nirS gene was closely related to Pseudomonadales and Burkholderiales, and the nosZ gene was closely related to Rhodospirillales, Rhizobiales, Pseudomonadales, and Alteromonadales. qPCR results showed that the abundance of these three genes (nirK, nirS and nosZ) reached the peak value in the late thermophilic stage of composting and abundance of the nirK gene was higher than that of the nosZ gene and the nirS gene. Redundancy analysis (RDA) showed that the diversity of the nirK and nirS genes was significantly correlated with ammonium (p<0.05), the diversity of the nosZ gene was significantly correlated with pH (p<0.05) and the abundance of the nirK nirS and nosZ genes was significantly correlated with temperature (p<0.05).

Analyzing the significant environmental factors on the spatial and temporal distribution of water quality utilizing multivariate statistical techniques: a case study in the Balihe Lake, China.

The assessment of surface water quality is significant to the management of aquatic ecosystem. In this research, in Balihe Lake which is an agricultural watershed lake, 11 environmental parameters (pH, water temperature, water depth, turbidity, DO, COD, TN, NH4+-N, NO3--N, TP, Chl-a) are monitored at 45 sampling sites in four seasons (winter of 2016, spring, summer, and autumn of 2017). With these monitoring data, two kinds of multivariate statistical methods including cluster analysis (CA) and principal component analysis (PCA) are applied to evaluate the spatial and temporal characteristics of the surface water quality. The results reveal that the spatial clusters (less, moderately, and highly polluted sections) of 45 sampling sites classified by the CA method are exactly consistent with the geographical distribution of these sampling sites, which rely on water quality meliorating downstream. From the perspective of time scale, the correlations between environmental parameters generated by the PCA method reveal that the main factors affecting the surface water quality are different in the four seasons. For the whole study period, which is a longer time scale rather than season, the main factors are also different to that of any season. Large time scale may weaken the effect and potential risk of nutrients on water quality, and it is therefore reasonable to select seasonal scale for the study of water quality in an agricultural watershed by using PCA. The results of this research may demonstrate significance to the identification of the main pollution factors and water quality assessment in freshwater lake with multivariate statistical methods.

The physiological and metabolic changes in sugar beet seedlings under different levels of salt stress.

Salinity stress is a major limitation to global crop production. Sugar beet, one of the world's leading sugar crops, has stronger salt tolerant characteristics than other crops. To investigate the response to different levels of salt stress, sugar beet was grown hydroponically under 3 (control), 70, 140, 210 and 280 mM NaCl conditions. We found no differences in dry weight of the aerial part and leaf area between 70 mM NaCl and control conditions, although dry weight of the root and whole plant treated with 70 mM NaCl was lower than control seedlings. As salt concentrations increased, degree of growth arrest became obvious In addition, under salt stress, the highest concentrations of Na+ and Cl- were detected in the tissue of petioles and old leaves. N and K contents in the tissue of leave, petiole and root decreased rapidly with the increase of NaCl concentrations. P content showed an increasing pattern in these tissues. The activities of antioxidant enzymes such as superoxide dismutase, catalase, ascorbate peroxidase and glutathione peroxidase showed increasing patterns with increase in salt concentrations. Moreover, osmoprotectants such as free amino acids and betaine increased in concentration as the external salinity increased. Two organic acids (malate and citrate) involved in tricarboxylic acid (TCA)-cycle exhibited increasing contents under salt stress. Lastly, we found that Rubisco activity was inhibited under salt stress. The activity of NADP-malic enzyme, NADP-malate dehydrogenase and phosphoenolpyruvate carboxylase showed a trend that first increased and then decreased. Their activities were highest with salinity at 140 mM NaCl. Our study has contributed to the understanding of the sugar beet physiological and metabolic response mechanisms under different degrees of salt stress.