[Impacts of Land Use Intensification Level on Fluvo-aquic Cropland Soil Microbial Community Abundance and Necromass Accumulation in North China].

Despite the essential role of soil microorganisms in nutrient turnover in soil ecological systems and the recognized paramount significance of microbial necromass to soil organic carbon accumulation, how microbial community abundance and necromass respond to land use intensification level regulation remains poorly understood. To address this knowledge gap, based on the land use intensification level, three treatments were set up[annual wheat-maize rotation (CC), alternating temporary grassland with wheat planting (TG), and perennial grassland (PG)], and a long-term fixed filed experiment was established to investigate the influences of the regulation of land use intensification level on bacterial and fungal community abundances; the accumulation of bacterial, fungal, and total microbial necromass; and their contributions to SOC sequestration using droplet digital PCR and amino sugar detection technologies. We further sought to determine the key factors driving the bacterial, fungal, and total microbial necromass C accumulation. Our results demonstrated that fungal community abundance was strongly affected by land use intensification level regulation compared to that of the bacterial community, which increased with decreasing land use intensification level. The total microbial necromass C predominated the SOC accumulation across all three land use intensification levels, which contributed 52.78%, 58.36%, and 68.87% to SOC, respectively, exhibiting an increasing trend with the decline in land use intensification level. Fungal necromass C accounted for more than 80% of the total microbial necromass C, indicating its predominance in the accumulation of the total microbial necromass C and active variation via the reduction in land use intensification level. There was no significant difference in bacterial necromass C (MurA) content, with the trend of CC

[Impacts of Co-application of Chemical Fertilizer Reduction and Organic Material Amendment on Fluvo-aquic Soil Microbial N-cycling Functional Gene Abundances and N-converting Genetic Potentials in Northern China].

The emerging environment-associated issues due to the overuse of inorganic fertilizers in agricultural production are of global concern despite the benefit of high yields. Eco-friendly organic materials with the capability to fertilize soil are encouraged to partially replace mineral fertilizer. The N cycle conducted by soil microorganisms is the most important biogeochemical process, dictating the N bioavailability in farmland ecosystems; however, little is known about how organic material amendment affects soil microbial N cycling under chemical fertilizer reduction. Hence, a fixed field trial with five fertilization practices was implemented to experimentally alter microorganisms essential for the soil N cycle, including conventional chemical fertilization (NPK), reduced chemical fertilization (NPKR), reduced chemical fertilization plus straw (NPKRS), reduced chemical fertilization plus organic fertilizer (NPKRO), and reduced chemical fertilization plus organic fertilizer and straw (NPKROS). The microbial N-cycling gene abundances and associated N-converting genetic potentials were evaluated using real-time quantitative PCR. In comparison to conventional chemical fertilization (NPK), organic addition significantly increased the amounts of heterotrophic microbes involved in organic N decomposition, N fixation, and N reduction; however, it reduced autotrophic microbes performing ammonia oxidization. Consequently, the overall proportion of heterotrophic microbes was remarkably enhanced, and the autotrophic proportion was correspondingly lowered. The fertilization practice shift significantly improved N fixation and gaseous N emission potentials, whereas it suppressed NO3- leaching potential. A significant discrepancy among five fertilization treatments was observed based on functional gene abundances (PERMANOVA, P=0.002),as revealed by distance-based redundancy analysis (db-RDA), with NH4+ as the dominant factor. Organic fertilizer addition was beneficial for heterotrophic N functional microorganisms, with simultaneous input of straw augmenting such an effect. Pearson's correlation analysis revealed that N storage and gaseous N emission potentials were both substantially negatively correlated with NH4+; NO3- leaching potential was notably negatively associated with SOC and TN but significantly related to NH4+. In conclusion, chemical fertilizer reduction combined with organic material amendments, a main fertilization recommendation, may enhance soil N storage, diminish N loss by leaching, and mitigate the environmental risk of N2O emission. This deserves attention considering that healthy and sustainable agricultural soil environment can be cultivated from the view of microbial N-cycling.

Multi-View Random-Walk Graph Regularization Low-Rank Representation for Cancer Clustering and Differentially Expressed Gene Selection.

Cancer genome data generally consists of multiple views from different sources. These views provide different levels of information about gene activity, as well as more comprehensive cancer information. The low-rank representation (LRR) method, as a powerful subspace clustering method, has been extended and applied in cancer data research. Although the multi-view learning methods based on low rank representation have achieved good results in cancer multi-omics analysis because they fully consider the consistency and complementarity between views, these methods have some shortcomings in mining the potential local geometry of data. In view of this, this paper proposes a new method named Multi-view Random-walk Graph regularization Low-Rank Representation (MRGLRR) to comprehensively analyze multi-view genomics data. This method uses multi-view model to find the common centroid of view. By constructing a joint affinity matrix to learn the low-rank subspace representation of multiple sets of data, the hidden information of each view is fully obtained. In addition, this method introduces random walk graph regularization constraint to obtain more accurate similarity between samples. Different from the traditional graph regularization constraint, after constructing the KNN graph, we use the random walk algorithm to obtain the weight matrix. The random walk algorithm can retain more local geometric information and better learn the topological structure of the data. What's more, a feature gene selection strategy suitable for multi-view model is proposed to find more differentially expressed genes with research value. Experimental results show that our method is better than other representative methods in terms of clustering and feature gene selection for cancer multi-omics data.

Adaptive Total-Variation Regularized Low-Rank Representation for Analyzing Single-Cell RNA-seq Data.

High-throughput sequencing of single-cell gene expression reveals a complex mechanism of individual cell's heterogeneity in a population. An important purpose for analyzing single-cell RNA sequencing (scRNA-seq) data is to identify cell subtypes and functions by cell clustering. To deal with high levels of noise and cellular heterogeneity, we introduced a new single cell data analysis model called Adaptive Total-Variation Regularized Low-Rank Representation (ATV-LRR). In scRNA-seq data, ATV-LRR can reconstruct the low-rank subspace structure to learn the similarity of cells. The low-rank representation can not only segment multiple linear subspaces, but also extract important information. Moreover, adaptive total variation also can remove cell noise and preserve cell feature details by learning the gradient information of the data. At the same time, to analyze scRNA-seq data with unknown prior information, we introduced the maximum eigenvalue method into the ATV-LRR model to automatically identify cell populations. The final clustering results show that the ATV-LRR model can detect cell types more effectively and stably.

Aromatic Aza-Claisen Rearrangement of Arylpropargylammonium Salts Generated in situ from Arynes and Tertiary Propargylamines.

The charge-accelerated aza-Claisen rearrangement of ammonium salts serves as a key step in the construction of complex nitrogen-containing molecules. However, much less attention has been paid to the aromatic aza-Claisen rearrangement than to the aliphatic one. Herein, we report an unprecedented aromatic aza-Claisen rearrangement of arylpropargylammonium salts, generated in situ from arynes and tertiary propargylamines, delivering structurally diverse 2-propargylanilines in moderate to good yields with high regioselectivity. This rearrangement proceeds in the absence of strong bases or transition metals, is compatible with moisture and air, tolerates a wide variety of functional groups, and is amenable to forming 11- to 13-membered heterocycles with a triple bond. The 2-propargylaniline products were treated with aluminum chloride in ethanol to afford multisubstituted indoles in moderate to excellent yields. Finally, a series of deuterium-labeling experiments was performed to elucidate the reaction mechanism.

Application of three dimensional (3D) curved multi-planar reconstruction images in 3D printing mold assisted eyebrow arch keyhole microsurgery.

OBJECTIVE: The application of multi-planar reconstruction of three dimensional (3D) curved surface in microsurgery of 3D printing mold assisted eyebrow arch keyhole approach was studied. METHODS: Eighty patients with intracranial aneurysms who underwent treatment at our hospital were enrolled. The patients were divided into two groups: the traditional eyebrow keyhole approach microsurgery group (38 cases in the conventional treatment group) and the three-dimensional curved surface multi-plane reconstruction image combined with 3D printing technology assisted eyebrow keyhole approach microsurgery group (42 cases in the 3D printing assisted treatment group). The Hunt-Hess classification was used to make a preliminary estimation of the patient's condition. The 3D curved multi-planar reconstruction method was used to assist the surgical plan; CT scan was used to establish a 3D printing mold, and the patient's condition and surgical plan were accurately analyzed before surgery. The operative time and the size of the incision area were recorded; postoperative GOS score and postoperative complications were statistically investigated. RESULTS: The 3D printing assisted treatment group (70.13 ± 15.56), (411.26 ± 10.38) mm2 , the operative time and incision area were significantly shorter than the conventional treatment group (120.35 ± 20.46), (663.55 ± 13.54) mm2 , p < .05); the GOS score showed that the 3D printing-assisted treatment group was significantly higher than the conventional treatment group (p < .05). The postoperative complication rate was significantly lower in the 3D print-assisted treatment group (9.52%) than in the conventional treatment group (47.36%, p < .05); the cure of intracranial aneurysms in the 3D printing assisted treatment group was more thorough than that in the conventional treatment group, and the difference was significant (p < .05). CONCLUSION: Compared with the conventional eyebrow arch-hole approach microsurgery, the 3D surface multi-planar reconstruction image combined 3D printing assisted technology was safer and more effective, and the postoperative recovery was better and the incidence of complications was lower.

1,2-Aminohalogenation of arynes with amines and organohalides.

An unprecedented use of inexpensive organohalides as halogen electrophiles to trap the zwitterion intermediates generated from amines and arynes has been developed to access structurally diverse tertiary 2-haloanilines. Effective organohalides include carbon tetrachloride, hexachloroethane, N-chlorosuccinimide, carbon tetrabromide, fluorotribromomethane, N-bromosuccinimide, carbon tetraiodide, and N-iodosuccinimide.

A Dynamic Scale-Free Network Particle Swarm Optimization for Extracting Features on Multi-Omics Data.

Mining meaningful and comprehensive molecular characterization of cancers from The Cancer Genome Atlas (TCGA) data has become a bioinformatics bottleneck. Meanwhile, recent progress in cancer analysis shows that multi-omics data can effectively and systematically detect the cancer-related genes at all levels. In this study, we propose an improved particle swarm optimization with dynamic scale-free network, named DSFPSO, to extract features on multi-omics data. The highlights of DSFPSO are taking the dynamic scale-free network as its population structure and diverse velocity updating strategies for fully considering the heterogeneity of particles and their neighbors. Experiments of DSFPSO and its comparison with several state-of-the-art feature extraction approaches are performed on two public data sets from TCGA. Results show that DSFPSO can extract genes associated with cancers effectively.

Formal Insertion of Imines (or Nitrogen Heteroarenes) and Arynes into the C-Cl Bond of Carbon Tetrachloride.

The formal insertion of double and triple bonds into the C-Cl bond of carbon tetrachloride has enabled the full utilization of carbon tetrachloride in chemical synthesis. A range of unactivated imines and electron-deficient nitrogen heteroarenes served as effective sources of C=N bonds to react with arynes and carbon tetrachloride to afford functionalized anilines whose core structures are present in some valuable arthropodicides. Control experiments and DFT calculations suggest the involvement of a trichloromethyl anion intermediate.

Three-component carboarylation of unactivated imines with arynes and carbon nucleophiles.

With 2-(trimethylsilyl)aryl triflates as aryne precursors, an unprecedented three-component carboarylation reaction of unactivated imines with arynes and carbon nucleophiles has been developed to access a variety of functionalized tertiary amines under transition metal-free conditions. Suitable carbon nucleophiles include chloroform, acetonitrile, and methyl propiolate.

Down-regulation of BnDA1, whose gene locus is associated with the seeds weight, improves the seeds weight and organ size in Brassica napus.

Brassica napus L. is an important oil crop worldwide and is the main raw material for biofuel. Seed weight and seed size are the main contributors to seed yield. DA1 (DA means big in Chinese) is an ubiquitin receptor and negatively regulates seed size. Down-regulation of AtDA1 in Arabidopsis leads to larger seeds and organs by increasing cell proliferation in integuments. In this study, BnDA1 was down-regulated in B. napus by over expressed of AtDA1R358K , which is a functional deficiency of DA1 with an arginine-to-lysine mutation at the 358th amino acid. The results showed that the biomass and size of the seeds, cotyledons, leaves, flowers and siliques of transgenic plants all increased significantly. In particular, the 1000 seed weight increased 21.23% and the seed yield per plant increased 13.22% in field condition. The transgenic plants had no negative traits related to yield. The candidate gene association analysis demonstrated that the BnDA1 locus was contributed to the seeds weight. Therefore, our study showed that regulation of DA1 in B. napus can increase the seed yield and biomass, and DA1 is a promising target for crop improvement.

Fibronectin-binding protein, FbpA, is the adhesin responsible for pathogenesis of Listeria monocytogenes infection.

The role of fibronectin binding protein A (FbpA) in Listeria monocytogenes infection and its pathogenesis were studied in vivo and in vitro by constructing a fbpA-deficient mutant of L. monocytogenes (ΔfbpA). In vivo, ΔfbpA was less pathogenic in mutant mice than was wild-type L. monocytogenes. FbpA did not affect the amounts of various virulence-determining factors, including internalin B and listeriolysin O. However, adherence to, and invasion of, mouse hepatocytes by the ΔfbpA mutant were reduced. In contrast, adherence to, but not invasion of, the ΔfbpA mutant to macrophages was attenuated. Fibronectin contributed to the efficient adherence and invasion of wild-type L. monocytogenes, but not to those of the ΔfbpA mutant. Attenuation of adhesion and uptake of the ΔfbpA mutant were reversed by overexpression of FbpA in it. FbpA was not involved in intracellular growth, autophagy induction or actin tail formation. Thus, the present findings clearly show that FbpA acts as an important adhesion molecule of L. monocytogenes, especially regarding hepatocytes, without modulating the expression of other virulence factors that have been implicated in the pathogenesis of L. monocytogenes infection.

Mouse peptidoglycan recognition protein PGLYRP-1 plays a role in the host innate immune response against Listeria monocytogenes infection.

The role of mouse peptidoglycan recognition protein PGLYRP-1 in innate immunity against Listeria monocytogenes infection was studied. The recombinant mouse PGLYRP-1 and a polyclonal antibody specific to PGLYRP-1 were prepared. The mouse PGLYRP-1 showed antibacterial activities against L. monocytogenes and other Gram-positive bacteria. PGLYRP-1 mRNA expression was induced in the spleens and livers of mice infected with L. monocytogenes. The viable bacterial number increased, and the production of cytokines such as gamma interferon (IFN-γ) and tumor necrosis factor alpha (TNF-α) was reduced in mice when mice had been injected with anti-PGLYRP-1 antibody before infection. The levels of IFN-γ and TNF-α titers in the organs were higher and the viable bacterial number was reduced in mice injected with recombinant mouse PGLYRP-1 (rmPGLYRP-1) before infection. PGLYRP-1 could directly induce these cytokines in spleen cell cultures. The elimination of intracellular bacteria was upregulated in NMuLi hepatocyte cells overexpressing PGLYRP-1. The enhancement of the elimination of L. monocytogenes from the organs was observed in IFN-γ(-/-) mice by rmPGLYRP-1 administration but not in TNF-α(-/-) mice. These results suggest that PGLYRP-1 plays a role in innate immunity against L. monocytogenes infection by inducing TNF-α.

Virulence factor p60 of Listeria monocytogenes modulates innate immunity by inducing tumor necrosis factor alpha.

We investigated the effect of p60, a virulence factor of Listeria monocytogenes, on host immune response in vitro and in vivo. Administration of p60 before a sublethal infection with L. monocytogenes enhanced innate host resistance in naïve mice. Mouse macrophage RAW264.7 cells produced tumor necrosis factor (TNF)-alpha in response to stimulation with recombinant p60. Toll-like receptor 4 may be involved in TNF-alpha production from RAW264.7 cells and enhanced host resistance induced by p60 administration. Our findings demonstrated that p60 modulates innate immune responses against L. monocytogenes infection.