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We constructed two collections of targeted single gene deletion (SGD) mutants and two collections of targeted multi-gene deletion (MGD) mutants in Salmonella enterica sv Typhimurium 14028s. The SGD mutant collections contain (1), 3517 mutants in which a single gene is replaced by a cassette containing a kanamycin resistance (KanR) gene oriented in the sense direction (SGD-K), and (2), 3376 mutants with a chloramphenicol resistance gene (CamR) oriented in the antisense direction (SGD-C). A combined total of 3773 individual genes were deleted across these SGD collections. The MGD collections contain mutants bearing deletions of contiguous regions of three or more genes and include (3), 198 mutants spanning 2543 genes replaced by a KanR cassette (MGD-K), and (4), 251 mutants spanning 2799 genes replaced by a CamR cassette (MGD-C). Overall, 3476 genes were deleted in at least one MGD collection. The collections with different antibiotic markers permit construction of all viable combinations of mutants in the same background. Together, the libraries allow hierarchical screening of MGDs for different phenotypic followed by screening of SGDs within the target MGD regions. The mutants of these collections are stored at BEI Resources (www.beiresources.org) and publicly available.

The use of manganese oxide (MnOx)-based catalysts has gained significant recognition as a promising solution for the sustainable synthesis of value-added chemicals. These catalysts possess notable qualities such as exceptional catalytic performance, cost-effectiveness, stability, and environmentally friendly properties. This review provides an overview of three typical processes for constructing novel MnOx-based catalysts through vacancy engineering, facet engineering, and crystal-phase engineering. It then discusses advancements made in the past five years in the sustainable synthesis of value-added chemicals using these MnOx-based heterogeneous catalysts. This includes the aerobic oxidation of alcohols and hydrocarbons, homo/cross-coupling of C–N/N＝N bonds, and biomass transformation. The review emphasizes the crucial role played by vacancy engineering, crystal-phase engineering, and facet engineering of MnOx-based heterogeneous catalysts in sustainable chemical synthesis. Lastly, it discusses the general challenges and future directions of this exciting area of research. [ABSTRACT FROM AUTHOR]

Ferroptosis is an iron-dependent death mode mediated by the aggregation of lipid peroxides and lipid-reactive oxygen species. It is characterized by iron-dependent lipid peroxide accumulation accompanied by oxidoreductase deficiency. Pancreatic beta cell dysfunction and insulin resistance are two major causes of type 2 diabetes mellitus (T2DM). Iron accumulation and metabolism may play a role in the development of T2DM. The molecular mechanism of β cell apoptosis and iron death in T2DM were reviewed. In addition, we discuss recent insights on the relationship between the trace element iron and apoptosis of β cells in T2DM. [ABSTRACT FROM AUTHOR]

Data partitioning techniques are pivotal for optimal data placement across storage devices, thereby enhancing resource utilization and overall system throughput. However, the design of effective partition schemes faces multiple challenges, including considerations of the cluster environment, storage device characteristics, optimization objectives, and the balance between partition quality and computational efficiency. Furthermore, dynamic environments necessitate robust partition detection mechanisms. This paper presents a comprehensive survey structured around partition deployment environments, outlining the distinguishing features and applicability of various partitioning strategies while delving into how these challenges are addressed. We discuss partitioning features pertaining to database schema, table data, workload, and runtime metrics. We then delve into the partition generation process, segmenting it into initialization and optimization stages. A comparative analysis of partition generation and update algorithms is provided, emphasizing their suitability for different scenarios and optimization objectives. Additionally, we illustrate the applications of partitioning in prevalent database products and suggest potential future research directions and solutions. This survey aims to foster the implementation, deployment, and updating of high-quality partitions for specific system scenarios. [ABSTRACT FROM AUTHOR]

Blue phosphorene (BlueP), a theoretically proposed phosphorous allotrope with buckled honeycomb lattice, has attracted considerable interest due to its intriguing properties. Introducing chirality into BlueP can further enrich its physical and chemical properties, expanding its potential for applications. However, the synthesis of chiral BlueP remains elusive. Here, we demonstrate the growth of large-area BlueP films on Cu(111), with lateral size limited by the wafer dimensions. Importantly, we discovered that the BlueP is characterized by an ultraflat honeycomb lattice, rather than the prevailing buckled structure, and develops highly ordered spatial chirality plausibly resulting from the rotational stacking with the substrate and interface strain release, as further confirmed by the geometric phase analysis. Moreover, spectroscopic measurements reveal its intrinsic metallic nature and different characteristic quantum oscillations in the image-potential states, which can be exploited for a range of potential applications including polarization optics, spintronics, and chiral catalysis.Blue phosphorene (BlueP) is a 2D phosphorus allotrope predicted to host Dirac fermions and other interesting electronic properties. Here, the authors report the growth of large-area BlueP films with ordered chiral nanostructures on Cu(111) substrates, expanding the range of its potential applications. [ABSTRACT FROM AUTHOR]

The mixture of lignite (HM) and oil shale organic matter (OS), which was prepared from Huadian oil shale treated using acids, was copyrolyzed in a fixed-bed reactor at the temperatures of 350‒500°C. Gas chromatography, thermogravimetric analysis, and in situ Fourier-transform infrared (FT-IR) spectroscopy were used to characterize the pyrolysis products. The results showed that the experimental yields of solid product and hydrogen obtained from the copyrolysis were higher than the theoretical values, respectively. The in situ FT-IR results showed that the emissions of ‒OH, aliphatic C‒Hx, and C–O groups for HM, OS, and their mixture all increased with increasing temperature. Moreover, a microscopic description of the low-temperature pyrolysis of HM and OS is provided. OS contains a large content of aliphatic compounds that can produce enough H radicals to bind to the H-poor radicals produced from HM. The coupling of these two free radicals resulted in a decrease in the yield of H2, while an increase in the yield of solid product was obtained. [ABSTRACT FROM AUTHOR]

Objectives: Accumulating evidence are available on the efficacy of high-dose isoniazid (INH) for multidrug-resistant tuberculosis (MDR-TB) treatment. We aimed to perform a systematic review and meta-analysis to compare clinical efficacy and safety outcomes of high-dose INH-containing therapy against other regimes. Methods: We searched the following databases PubMed, Embase, Scopus, Web of Science, CINAHL, the Cochrane Library, and ClinicalTrials.gov. We considered and included any studies comparing treatment success, treatment unsuccess, or adverse events in patients with MDR-TB treated with high-dose INH (>300 mg/day or >5 mg/kg/day). Results: Of a total of 3,749 citations screened, 19 studies were included, accounting for 5,103 subjects, the risk of bias was low in all studies. The pooled treatment success, death, and adverse events of high-dose INHcontaining therapy was 76.5% (95% CI: 70.9%-81.8%; I²: 92.03%), 7.1% (95% CI: 5.3%-9.1%; I²: 73.75%), and 61.1% (95% CI: 43.0%-77.8%; I²: 98.23%), respectively. The high-dose INH administration is associated with significantly higher treatment success (RR: 1.13, 95% CI: 1.04-1.22; p < 0.01) and a lower risk of death (RR: 0.45, 95% CI: 0.32-0.63; p < 0.01). However, in terms of other outcomes (such as adverse events, and culture conversion rate), no difference was observed between high-dose INH and other treatment options (all p > 0.05). In addition, no publication bias was observed. Conclusion: In MDR-TB patients, high-dose INH administration is associated with a favorable outcome and acceptable adverse-event profile. [ABSTRACT FROM AUTHOR]

A bacterial strain, Gram staining positive, strictly aerobic, rod-shaped, motile bacterium with flagellum and endospore-forming, designated strain YIM B05605T, was isolated from soil sampled in Hamazui hot springs, Tengchong City, Yunnan province, China. Optimum growth for the strain occurred at pH 7.0 and 45 °C. MK-7 was the main menaquinone in the strain YIM B05605T. The diagnostic diamino acid in the cell-wall peptidoglycan was meso-diaminopimelic acid. Diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), phosphatidylmonomethylethanolamine (PME), unidentified glycolipid (GL), three unknown aminophospholipids (APLs) and unidentified polarlipid (PL) were part of the polar lipid profile. The major fatty acids were anteiso-C15:0 and iso-C16:0. The DNA G + C content of the type strain was 58.76%. Genome-based phylogenetic analysis confirmed that strain YIM B05605T formed a distinct phylogenetic cluster within the genus Cohnella. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values of strain YIM B05605T with the most related species C. fontinalis YT-1101T were 73.42% and 15.7%. Functional analysis by NR, Swiss-prot, Pfam, eggNOG, GO, KEGG databases revealed that strain YIM B05605T has 13 genes related to the sulfur cycle, 2 genes related to the nitrogen cycle. Based on phylogenomic and phylogenetic analyses coupled with phenotypic and chemotaxonomic characterizations, strain YIM B05605T could be classified as a novel species of the genus Cohnella, for which the name Cohnella caldifontis sp. nov., is proposed. The type strain is YIM B05605T (= CGMCC 1.60052T = KCTC 43462T = NBRC 115921T). [ABSTRACT FROM AUTHOR]

Superconductors with reduced dimensionality have been widely explored for their exotic superconducting behaviors. Especially, at the two-dimensional limit, two-monolayer Pb films with two types of structures provide an ideal platform to unveil the underlying superconducting mechanism [Science324, 1314 (2009)]. Here, by combining scanning tunneling microscopy (STM) with the first-principle calculations, we successfully identify that these two types have different atomic lattice structures with varying stacking phases, which further enables us to calculate the phonon spectrum and electron phonon coupling strength of each type. The theoretical calculations are in good agreement with tunneling spectroscopy measurements of the superconducting transition temperatures (Tc), which established a correlation between atomic structures and superconductivity. Moreover, it was observed that the higher Tc of these two types also possess higher out-of-plane upper critical magnetic fields (Hc2). These findings will provide important new insights into two-dimensional superconductivity at the atomic level. [ABSTRACT FROM AUTHOR]

To reveal the molecular structure characteristics of the caking components in coal, three coals with different ranks were treated using a new synthetic ionic liquid (i.e., [N4441][NO3]), the combination of which is based on the effect degree of different anions and cations of ionic liquids on the caking properties of the coals. Additionally, the raw and treated coals were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman. The results showed that the caking index (G) values of the coals decreased after [N4441][NO3] treatment, and the destruction degree decreased with increasing coal rank. The decrease in G is related to the removal of some species during [N4441][NO3] treatment. FTIR and Raman showed that aromatics with 3 or more rings but less than that in graphite and long-chain aliphatics were removed. XRD showed that [N4441][NO3] treatment decreased the graphitization degrees of the coals. Additionally, a mechanism of destroying the caking property of coal using [N4441][NO3] is proposed. [N4441][NO3] treatment could decrease the contents of aromatics with 3 or more rings but less than that in graphite and long-chain aliphatics. Consequently, the caking property of coal is destroyed. [ABSTRACT FROM AUTHOR]

We proposed a low-temperature slow pyrolysis treatment (LTSPT) to improve the caking property of Shenmu long flame coal (SMCY). To reveal the factors affecting the caking property of SMCY, Fourier transform infrared spectroscopy, solid-state 13C nuclear magnetic resonance spectroscopy, Raman spectroscopy, and pyrolysis-gas chromatography with mass spectrometric were used to analyze the changes in the chemical properties of the pyrolysis products. The results showed that LTSPT could significantly improve the caking index of SMCY, and it increased with the increase in temperature. LTSPT could decrease the content of oxygen; therefore, the consumption of hydrogen decreased, indicating that the increased hydrogen radicals can be produced, which serve as stabilizers for the aromatic radicals generated from coal pyrolysis. As a result, relatively high-molecular weight aromatic free radicals are inhibited from cross-linking into semi-coke. On the other hand, SMCY with a suitable upgrading degree possessed a suitable content of aromatic hydrocarbons, which are precursors of caking components. The combined effects of the abovementioned two factors led to the increase in caking index. [ABSTRACT FROM AUTHOR]

Abstract The phylogeography of the European wild boar was mainly determined by postglacial recolonization patterns from Mediterranean refugia after the last ice age. Here we present the first analysis of SNP polymorphism within the complete mtDNA genome of West Russian (n = 8), European (n = 64), and North African (n = 5) wild boar. Our analyses provided evidence of unique lineages in the East‐Caucasian (Dagestan) region and in Central Italy. A phylogenetic analysis revealed that these lineages are basal to the other European mtDNA sequences. We also show close connection between the Western Siberian and Eastern European populations. Also, the North African samples were clustered with the Iberian population. Phylogenetic trees and migration modeling revealed a high proximity of Dagestan sequences to those of Central Italy and suggested possible gene flow between Western Asia and Southern Europe which was not directly related to Northern and Central European lineages. Our results support the presence of old maternal lineages in two Southern glacial refugia (i.e., Caucasus and the Italian peninsula), as a legacy of an ancient wave of colonization of Southern Europe from an Eastern origin.

Xanthomonas oryzea pv. oryzae (Xoo) is the causal agent of bacterial blight of rice, which is a significant threat to many of rice-growing regions. The type III secretion system (T3SS) is an essential virulence factor in Xoo. Expression of the T3SS is often induced in the host environment or in hrp-inducing medium but is repressed in nutrient-rich medium. The elucidation of molecular mechanism underlying induction of T3SS genes expression is a very important step to lift the veil on global virulence regulation network in Xoo. Thus, an efficient and reliable genetic tool system is required for detection of the T3SS proteins. In this study, we constructed a protein expression vector pH3-flag based on the backbone of pHM1, a most widely used vector in Xoo strains, especially a model strain PXO99A. This vector contains a synthesized MCS-FLAG cassette that consists of a multiple cloning site (MCS), containing a modified pUC18 polylinker, and Flag as a C-terminal tag. The cassette is flanked by transcriptional terminators to eliminate interference of external transcription enabling detection of accurate protein expression. We evaluated the potential of this expression vector as T3SS proteins detection system and demonstrated it is applicable in the study of T3SS genes expression regulation in Xoo. This improved expression system could be very effectively used as a molecular tool in understanding some virulence genes expression and regulation in Xoo and other Xanthomonas spp.

Different pretreatments can affect the quality of Hypsizygus marmoreus (HM). In this study, the effects of thermal treatment or combined with color protection and hardening on color, texture, microstructure, polyphenol oxidase (PPO) and Peroxidase (POD) C-1: Explain the first time? activities, and the volatile components of HM were investigated. The results showed compared with the control group, both heating group (H group) and color protection, hardening and heating (CHH group) significantly enhanced the color difference, and reduced all texture parameters as well as PPO and POD activities. Additionally, in two treatment groups, the structure of HM became loose, the amounts of alcohols, ketones, and aldehydes were changed significantly. Compared with the H group, the color difference and PPO activities in CHH group were significantly decreased, while all texture parameters were increased significantly, the fibers of HM showed regular arrangement. In conclusion, the combination of CHH performed better effects on hardness, chewiness, microstructure, and enzymes activities related to enzymatic browning.

Cattle are naturally infected with Salmonella enterica serotype Typhimurium and exhibit pathological features of enteric salmonellosis that closely resemble those in humans. Cattle are the most relevant model of gastrointestinal disease resulting from nontyphoidal Salmonella infection in an animal with an intact microbiota. We utilized this model to screen a library of targeted single-gene deletion mutants to identify novel genes of Salmonella Typhimurium required for survival during enteric infection. Fifty-four candidate mutants were strongly selected, including numerous mutations in genes known to be important for gastrointestinal survival of salmonellae. Three genes with previously unproven phenotypes in gastrointestinal infection were tested in bovine ligated ileal loops. Two of these mutants, STM3602 and STM3846, recapitulated the phenotype observed in the mutant pool. Complementation experiments successfully reversed the observed phenotypes, directly linking these genes to the colonization defects of the corresponding mutant strains. STM3602 encodes a putative transcriptional regulator that may be involved in phosphonate utilization, and STM3846 encodes a retron reverse transcriptase that produces a unique RNA-DNA hybrid molecule called multicopy single-stranded DNA. The genes identified in this study represent an exciting new class of virulence determinants for further mechanistic study to elucidate the strategies employed by Salmonella to survive within the small intestines of cattle.

Cattle are naturally infected with Salmonella enterica serotype Typhimurium and exhibit pathological features of enteric salmonellosis that closely resemble those in humans. Cattle are the most relevant model of gastrointestinal disease resulting from nontyphoidal Salmonella infection in an animal with an intact microbiota. We utilized this model to screen a library of targeted single-gene deletion mutants to identify novel genes of Salmonella Typhimurium required for survival during enteric infection. Fifty-four candidate mutants were strongly selected, including numerous mutations in genes known to be important for gastrointestinal survival of salmonellae. Three genes with previously unproven phenotypes in gastrointestinal infection were tested in bovine ligated ileal loops. Two of these mutants, STM3602 and STM3846, recapitulated the phenotype observed in the mutant pool. Complementation experiments successfully reversed the observed phenotypes, directly linking these genes to the colonization defects of the corresponding mutant strains. STM3602 encodes a putative transcriptional regulator that may be involved in phosphonate utilization, and STM3846 encodes a retron reverse transcriptase that produces a unique RNA-DNA hybrid molecule called multicopy single-stranded DNA. The genes identified in this study represent an exciting new class of virulence determinants for further mechanistic study to elucidate the strategies employed by Salmonella to survive within the small intestines of cattle.

In this study, mesoporous Cu and N co-doped TiO2 crystals were synthesized with Cu and N co-doped titania xerogel by solvothermal treatment in different alcohols and the characteristics of Cu and N co-doped TiO2 were investigated with XRD, SEM, UV-vis and N2 sorption analysis. Results indicated that different alcohols facilitated formation and stability of pure anatase phase. The photocatalytic activity of samples was evaluated by the photocatalytic oxidation of acetone under visible light.The extraordinary photocatalytic performance of the Cu and N co-doped TiO2 crystals were synthesized with titania xerogel by solvothermal treatment in ethyl alcohol. This enhanced photoactivity is related to the bandgap narrowing, good dispersibility, the smaller pores and the larger specific area. DOI: http://dx.doi.org/10.5755/j01.ms.24.4.18568