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In view of the serious deformation and failure of surrounding rock of high stress mining roadway near fault in the Shandong Xuchang Coal Mine, the support scheme and instability characteristics of the original mining roadway were analyzed by combining field measurement and numerical simulation. The asymmetric stability law of the mining roadway under the multiple superposition of fault structure, lateral abutment pressure of adjacent goaf and advanced abutment pressure of working face was studied. In this paper, according to the actual conditions of the 3318 working face belt transportation roadway in Xuchang Coal Mine, a new bolt-mesh support scheme with high strength, high stiffness and asymmetric characteristics is proposed. In this scheme, the 3318 working face belt transportation roadway is divided into two supporting sections A and B for layout. Through the field test, it is concluded that the deformation of surrounding rock of the 3318 working face belt conveyor roadway is reduced by more than 70 % after adopting the high strength and high stiffness asymmetric new anchor net support scheme. The relative displacement of roof and floor is reduced from 500 mm to 120 mm, and the relative displacement of two sides is reduced from 800 mm to 110 mm.

Aeschynomene indica rhizobia (AIRs) are special classes of bacteria capable of nodulating without nodulation factors and have photosynthetic capacity. With an aim to characterize the structural variations in Bradyrhizobium genomes during its evolution, the genomes of AIRs and the reference Bradyrhizobium strains were compared utilizing molecular biology, bioinformatics, and biochemistry techniques. The presence of symbiotic nitrogen fixation (nif) genes and photosynthetic genes, as well as components of the T3SS (Type III secretion system) and T3CP (Type III chaperone) in the genome of AIRs, was also assessed. Additionally, the origin, evolutionary history, and genes associated with the NF-independent nodulation pattern in AIRs were explored. The results indicate that horizontal gene transfer events have occurred in AIRs, and three distinct origins of AIRs were estimated: early differentiated AIRs, non-symbiotic Bradyrhizobium, and non-AIRs. In contrast to the significant genetic transformations observed in the second and third groups, the first group of AIRs displays a rich evolutionary history, exhibits high species diversity, and primarily relies on vertical transmission of nitrogen fixation and photosynthetic genes. Overall, the findings provide a fundamental theoretical foundation for gaining a deeper understanding of the phylogeny and genealogy of AIRs. [ABSTRACT FROM AUTHOR]

The accumulation of high amounts of plastic waste in the environment has raised ecological and health concerns, particularly in croplands, and biological degradation presents a promising approach for the sustainable treatment of this issue. In this study, a polyvinyl chloride (PVC)-degrading bacterium was isolated from farmland soil samples attached to waste plastic, utilizing PVC as the sole carbon source. The circular chromosome of the strain Cbmb3, with a length of 5,768,926 bp, was subsequently sequenced. The average GC content was determined to be 35.45%, and a total of 5835 open reading frames were identified. The strain Cbmb3 was designated as Bacillus toyonensis based on phylogenomic analyses and genomic characteristics. The bioinformatic analysis of the Cbmb3 genome revealed putative genes encoding essential enzymes involved in PVC degradation. Additionally, the potential genomic characteristics associated with phytoprobiotic effects, such as the synthesis of indole acetic acid and secondary metabolite synthesis, were also revealed. Overall, the present study provides the first complete genome of Bacillus toyonensis with PVC-degrading properties, suggesting that Cbmb3 is a potential strain for PVC bioremediation and application. [ABSTRACT FROM AUTHOR]

A vertex subset S of a digraph D is called a dominating set of D if every vertex not in S is adjacent from at least one vertex in S. The domination number of a digraph D, denoted by γ(D), is the minimum cardinality of a dominating set of D. A Roman dominating function (RDF) on a digraph D is a function f : V (D) → {0, 1, 2} satisfying the condition that every vertex v with f(v) = 0 has an in-neighbor u with f(u) = 2. The weight of an RDF f is the value ω (f) =Σv∈V(D)f(v). The Roman domination number of a digraph D, denoted by γR(D), is the minimum weight of an RDF on D. In this paper, for any integer k with 2 ≤ k ≤ γ(D), we characterize the digraphs D of order n ≥ 4 with δ−(D) ≥ 1 for which γR(D) = (D) + k holds. We also characterize the digraphs D of order n ≥ k with γR(D) = k for any positive integer k. In addition, we present a Nordhaus-Gaddum bound on the Roman domination number of digraphs.

Background: Observational studies have suggested an association between lipid‐lowering drugs and inflammatory bowel disease (IBD) risk. This study aimed to assess the causal influence of lipid‐lowering agents on IBD risk using Mendelian randomization analysis. Method: In a population of 173,082 individuals of European ancestry, 55 single‐nucleotide polymorphisms were identified as instrumental variables for 6 lipid‐lowering drug targets (HMGCR, NPC1LC, PCSK9, LDLR, CETP and APOB). Summary statistics for the genome‐wide association study of IBD, ulcerative colitis (UC) and Crohn's disease (CD) were obtained from the FinnGen consortium, Program in Complex Trait Genomics and UK Biobank. Inverse‐variance weighted was employed as the primary MR method, and odds ratios (ORs) with 95% confidence intervals were reported as the results. Sensitivity analyses using conventional MR methods were conducted to assess result robustness. Results: Gene‐proxied inhibition of Niemann‐Pick C1‐like 1 (NPC1L1) was associated with an increased IBD risk (OR [95% CI]: 2.31 [1.38, 3.85]; p =.001), particularly in UC (OR [95% CI]: 2.40 [1.21, 4.74], p =.012), but not in CD. This finding was replicated in the validation cohort. Additionally, gene‐proxied inhibition of low‐density lipoprotein receptor was associated with reduced IBD (OR [95% CI]:.72 [.60,.87], p <.001) and UC risk (OR [95% CI]:.74 [.59,.92], p =.006), although this result was not replicated in the validation cohort. Other drug targets did not show significant associations with IBD, UC or CD risk. Conclusion: Inhibition of the lipid‐lowering drug‐target NPC1L1 leads to an increased IBD risk, mainly in the UC population. [ABSTRACT FROM AUTHOR]