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The one-dimensional premixed laminar freely propagating flame was used to numerically simulate the laminar combustion characteristics of primary reference fuel (PRF). The equivalence ratios are set as 0.7–1.5 at initial temperatures of 298, 358, and 403 K, initial pressures of 1, 2, and 5 atm. Laminar burning velocity (LBV), adiabatic flame temperature (AFT) and mole fractions of H, CO, CO2, C2H4 at Φ = 1.0 are investigated. Meanwhile, temperature sensitivity, rate of production (ROP) and reaction pathway are analyzed. The results show that LBV and AFT decrease with n-heptane doping ratios increasing. With the increase of initial temperatures, the LBV and AFT increase. With the increase of initial pressures, the LBV decreases, while AFT increases slightly. Through temperature sensitivity analysis, it can be found that R1 H + O2 ⇔ O + OH and R97 OH + CO⇔ H + CO2 are main exothermic reactions. R12 H + OH + M ⇔ H2O + M and R56 H + CH3(+M) ⇔ CH4(+M) are major endothermic reactions. n-Heptane is decomposed into C2H4 and C2H3, and iso-octane is decomposed into CH3, CH3O, and CH2O. These small molecule species are further oxidized to generate HCO, which is finally changed into CO2.

Given the serious threat of foodborne multidrug-resistant bacteria to animals and humans, finding an effective antibacterial compound has always been an important topic for scientists. Here, from the soil of Changbaishan, we have identified a bacterium that can inhibit the growth of Staphylococcus aureus. Nr genome database analysis and phylogenetic analysis showed that strain CB6 belongs to Bacillus velezensis. We found that the crude extract of strain CB6 has broad-spectrum antibacterial activity against foodborne pathogens. In addition, we showed that the crude extract loses antibacterial activity after treatment with papain. Next, strain CB6 was purified using ammonium sulfate precipitation, a Sephadex G-75 gel filtration column and high-performance liquid chromatography system (HPLC). Liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis indicated that the antibacterial compound was the protein ATP synthase subunit α (ATP-1), with a molecular weight of 55.397 KDa. Moreover, we reported the complete genome sequence of strain CB6, which is composed of a unique circular 3,963,507 bp chromosome with 3749 coding genes and a G + C content of 46.53%. The genome contained 12 gene clusters with antibacterial functions, which constituted over 20.947% of the complete genome. Of note, the amino acid sequence encoding the ATP-1 protein in the strain CB6 genome was identified. In addition to these findings, we speculate that the ATP-1 protein may provide energy for secondary metabolites, which in turn will improve the antibacterial activity of the secondary metabolites. All the above important features make the ATP-1 as a potential candidate for the development of new antibacterial drugs and food preservatives in the future.

Koi carp (Cyprinus carpio) are well-known and highly valuable fish in the international ornamental fish community that have been plagued by Aeromonas veronii infections in recent years. Some A. veronii infections are serious enough to cause death. Lactobacillus plantarum, a probiotic, is one of the most environmentally friendly and safe alternatives to antibiotics for use as a feed additive for aquatic animals such as fish. The present study investigated the effects of L. plantarum C20015 on growth performance, immune responses, and eradication of A. veronii infection in koi carp. During a 6-week feeding experiment in an indoor aquarium and a 14-day A. veronii artificial infection experiment, a control diet group was fed with untreated feed twice a day, while experimental groups were given different concentrations of L. plantarum in their feed. The results indicated that the specific growth rate and percent weight gain of fish were significantly higher in the experimental groups than in the control diet group (P < 0.05). The activity of superoxide dismutase (SOD), peroxidase (POD), and lysozyme (LZM) and the levels of IgM antibody were significantly higher in the L. plantarum–supplemented groups than in the control diet group, and the enzymatic activity in the 108 CFU/g C20015 group was higher than that in the 107 CFU/g C20015 and 109 CFU/g C20015 groups (P < 0.01). In contrast, alkaline phosphatase (AKP) activity in the experimental groups was the highest at 42 days. All fish in the control diet group died 7 days after A. veronii infection. After 14 days, the relative percent survival (%, RPS) of the fish in the L. plantarum–supplemented groups was significantly higher than that of the fish in the control group, and the 108 CFU/g C20015 group had the highest RPS. Therefore, we first reported that fish fed with 108 CFU/g of L. plantarum C20015 could promote food intake and growth for koi carp.

Proline-rich antimicrobial peptides (PR-AMPs) have attracted much interest as they target Gram-negative and do not act by lytic mechanisms. In this study, a novel hybrid peptide OM19R was designed based on the Oncocin and MDAP-2. OM19R showed specific and improved potency against Escherichia coli (E. coli), Salmonella and Shigella standard strains compared to parental peptides. The minimum inhibitory concentrations (MICs) ranged from 1 to 2 μM. However, the activity against Klebsiella pneumoniae (K. pneumoniae) was inhibited. The dependence of the SbmA protein for OM19R activity was also studied by a gene-knockout strain. The confocal laser scanning microscopy further revealed that OM19R could rapidly penetrate into E. coli cells without membrane damage. In summary, the hybrid peptide OM19R is a strong cell-selective antibacterial peptide and a promising specific antibacterial agent.

Isolation and characterization of a bacteriocin from Brevibacillus laterosporus DS-3 and its ability in producing antibacterial activity were examined in this study. We isolated 48 bacterial strains from different native ecological niches. Sources included lake water, soil, air, and food. Among the isolates from the soil sample, morphological and biochemical tests identified Brev. laterosporus DS-3, which showed great potential for bacteriocin production. It was purified by ammonium sulfate precipitation, then applied in a Sephadex G-15 gel filtration column connected to a purification of AKTA Pure (USA) and reverse phase chromatography. MALDI-TOF mass spectrometry indicated that bacteriocin DS-3 has a low molecular weight of 1592.579 Da. LNTLETEEWFFK was identified as the sequence by mass spectrometry analysis in tandem liquid chromatography and MASCOT research. This bacteriocin inhibited Gram-positive and Gram-negative bacteria and was effective against Methicillin-resistant Staphylococcus aureus (MRSA). Brev. laterosporus DS-3 present in here is thermostable and tolerant to extreme pH. However, inactivation of its antibacterial activity was observed when treated with papain and trypsin but not pepsin, proteinase K, and catalase.

Trueperella pyogenes (T. pyogenes) is a worldwide known pathogen of domestic ruminants and pigs causing a wide variety of infections. The objective of this study was to report the presence of major virulence genes in T. pyogenes isolated from pigs with respiratory clinical signs and determine their resistance to antibiotics at the same time. A total of 27 T. pyogenes strains were obtained from Jilin Province, and the nanH, nanP, cbpA, fimC, and fimE virulence genes were detected in 7 (25.9%), 14 (51.9%), 18 (66.7%), 8 (29.6%), and 16 (59.3%) isolates, respectively. All isolates were observed to harbor plo and fimA genes. However, 27 T. pyogenes strains tested negative for fimG gene. Antibiotic susceptibility tests revealed that the isolated strains had extensive drug resistance, all isolates were sensitive to fluoroquinolones and penicillins antibiotics, and high levels of resistance were found to gentamicin (77.8%), amikacin (74.1%), erythromycin (85.2%), and azithromycin (85.2%). These results highlights the need for prudent use of specific antimicrobial agents in veterinary clinical treatment.

Chalkbrood, which results from Ascosphaera apis infection, is one of the bee diseases that causes serious damage to the bee colony. Understanding the molecular bases underlying immune response to chalkbrood disease would facilitate the genetic breeding of bees by selecting races with superior chalkbrood resistance. In this study, transcriptome sequencing was performed to identify genes and pathways involved in the immune response to As. apis infection in A. mellifera larvae. In total, 2,890 differentially expressed genes (DEGs) (FDR

We aimed to determine the resistance mechanisms of 27 T. pyogenes isolates from swine in the Jilin province of China. Drug sensitivity analysis indicated that most of the isolated strains were resistant to aminoglycosides. We investigated the genes involved in target alteration, drug inactivation, and increased efflux as potential resistance mechanisms. Two known aminoglycoside resistance genes (aphA1 and strB) were not found in the genomic DNA of any isolate. A 3-bp (CCC) deletion in one 16S rRNA operon was detected in all isolates, and efflux pumps were not active in the resistant group. Ultimately, genes encoding aminoglycoside-modifying enzymes carried by class 1 integrons were identified as the main cause of resistance to aminoglycosides in T. pyogenes.

Eugenol, the major active essential oil component of clove, was reported to possess QS (quorum sensing) inhibitory activity. A previous study found that eugenol could bind to quorum sensing receptors of Pseudomonas aeruginosa and down-regulate the expression of Streptococcus mutans virulence genes at sub-MIC (minimum inhibitory concentration) without affecting the bacterial growth. However, the alterations of QS signal molecules at transcription levels was not well understood. To better understand interactions of Klebsiella pneumoniae in response to eugenol and explore molecular regulations, transcriptome sequencing was performed. A total of 5779 differentially expressed genes (DEGs) enriched in a variety of biological processes and pathways were identified. The transcriptional data was validated by qPCR and the results showed that the expression profiles of 4 major genes involved in autoinducers-2 (AI-2) synthesis, including luxS, pfs, and lsrK were consistent with transcriptome analysis except for lsrR, a transcriptional repressor gene of lsr operon, which may repress the expression of following genes responsible for AI-2 signal transmission in vivo. In vitro AI-2 synthesis assay also revealed that eugenol could inhibit AI-2 generation. The results of our study offer insights into the mechanisms of QS inhibitory activity and K. pneumoniae AI-2 alterations after eugenol treatment.

Trueperella pyogenes (T. pyogenes) is a well-known opportunistic pathogen of many animal species. It can cause a variety of suppurative infections. The objective of this research was to get insight into the gene context and the location of the antimicrobial resistance determinants in the two multi-resistant T. pyogenes isolates TP3 and TP4. Comparative analysis of key factors leading to antimicrobial resistance was performed. Both isolates were resistant to erythromycin, azithromycin and tetracycline, and susceptible to ciprofloxacin, enrofloxacin, cefazolin and florfenicol. In addition, TP4 was resistant to amikacin and gentamicin. Whole-genome analyses revealed that both TP3 and TP4 contained two different genomic islands (TP3-GI1, TP3-GI5, TP4-GI5 and TP4-GI8) involved in multi-drug resistance. There is a common region in TP3-GI1 and TP4-GI5, containing the tetracycline resistance gene tet(W) and a series of genes involved in type IV secretion systems. Several genes located on TP3-GI5 and TP4-GI8 are highly homologous. Tetracycline-resistance gene tet(33) was potentially acquired by horizontal gene transfer via IS6100 located on 57,936 bp TP3-GI5. The macrolide resistance gene erm(X) was located near the end of the TP3-GI5. The sequence analysis of TP4-GI8 showed that two copies of erm(X) and two IS1634 elements located in the same orientation may have formed a composite transposon. GI-type T4SS, transposons and multiple resistance genes located on GIs play a key role in multiple drug resistance of TP3 and TP4.

Eugenol, the major active essential oil component of clove, was reported to possess QS (quorum sensing) inhibitory activity. A previous study found that eugenol could bind to quorum sensing receptors of Pseudomonas aeruginosa and down-regulate the expression of Streptococcus mutans virulence genes at sub-MIC (minimum inhibitory concentration) without affecting the bacterial growth. However, the alterations of QS signal molecules at transcription levels was not well understood. To better understand interactions of Klebsiella pneumoniae in response to eugenol and explore molecular regulations, transcriptome sequencing was performed. A total of 5779 differentially expressed genes (DEGs) enriched in a variety of biological processes and pathways were identified. The transcriptional data was validated by qPCR and the results showed that the expression profiles of 4 major genes involved in autoinducers-2 (AI-2) synthesis, including luxS, pfs, and lsrK were consistent with transcriptome analysis except for lsrR, a transcriptional repressor gene of lsr operon, which may repress the expression of following genes responsible for AI-2 signal transmission in vivo. In vitro AI-2 synthesis assay also revealed that eugenol could inhibit AI-2 generation. The results of our study offer insights into the mechanisms of QS inhibitory activity and K. pneumoniae AI-2 alterations after eugenol treatment.

Pasteurella multocida (P. multocida) is an important pathogen that causes bovine respiratory disease (BRD) in China and other countries. To investigate the antimicrobial susceptibility of P. multocida isolated from different provinces in China, we analyzed antimicrobial susceptibility phenotypes and pulsed-field gel electrophoresis (PFGE) types of P. multocida; then, we sequenced the complete genome of strain found to be multidrug-resistant. The isolates exhibited resistance to many antimicrobial agents, especially amikacin, sulfamethoxazole, sulfachloropyridazinesodium, macrolides, and fluoroquinolones. Pulsed-field gel electrophoresis analysis showed that a clonal spread of multidrug-resistant isolates occurred in various provinces. All of the isolates carried class I integron.

The Japanese bigeye (Pristigenys niphonia) is a species in the genus Pristigenys and in the family Priacanthidae. To understand the phylogenetic relationship of Japanese bigeye in teleost, we firstly determined the complete mitochondrial genome of Japanese bigeye. The entire mitochondrial genome of Japanese bigeye is 16,519bp in length, including 13 protein-coding genes and 2 ribosomal RNA genes (rRNA), 22 transfer RNA genes (tRNAs), and 2 main non-coding regions. The overall base composition is 24.9% of T, 30.6% of C, 27.7% of A, and 16.8% of G. The gene arrangement, base composition, and tRNA structures of the complete mitochondrial genome of Japanese bigeye is consistent with those of other teleost. The complete mitochondrial genome of Japanese bigeye was used to construct phylogenetic tree, which shows that Japanese bigeye is clustered with the fishes of the order Perciformes. We expect that the availability of mitochondrial genome of Japanese bigeye will facilitate the further investigations of the taxonomic resolution, biogeography, and molecular systematic.

The objective was to add 0, 400, 800 or 1200 mg/kg of Hericium caput-medusae polysaccharide (HCMP) to the basal diet of grass carp (Ctenopharyngodon idella) and determine effects on humoral innate immunity, expression of immune-related genes and disease resistance. Adding HCMP enhanced (P 0.05) bactericidal activity at 1, 2 and 3 weeks and also lysozyme activity, complement C3, and SOD activity at 2 and 3 weeks. Supplementing 800 or 1200 mg/kg of HCMP for 2 or 3 weeks increased (P 0.05) serum concentrations of total protein, albumin and globulin. Two immune-related genes (IL-1β and TNF-α) were up-regulated (P 0.05) in HCMP supplemented groups given 800 or 1200 mg/kg HCMP after 2 and 3 weeks of feeding. Expression of anti-inflammatory cytokine IL-10 was down-regulated (P 0.05) after receiving 800 or 1200 mg/kg HCMP for 2 or 3 weeks. Fish fed 800 mg/kg HCMP had maximal disease resistance against Aeromonas hydrophila (65.4%). In conclusion, HCMP enhanced immune response and expression of immune-related genes and increased disease resistance against Aeromonas hydrophila in grass carp, with greatest effects in fish given 800 mg/kg HCMP for 3 weeks.

A nonlinear four-wheel dynamics vehicle model which includes a limit-slip differential model based on FSAE racecar is established and the typical conditions are designed according to track requirement. The effect of different locking ratio on vehicle handling stability has been researched .The simulation results shows that: with the increase of locking ratio, the steering radius ratio increase, both peak lateral acceleration and yaw angular velocity reduce, and the changing trend of value is flat. But the average acceleration increase with the locking ratio until the latter reach a specific value under the condition of Slaloms.

Three novel supramolecular polymers, [(Cd2Cl3)(H2O)2(N3)3 (bpe)] (bpe = 1,2-bis(pyridinium)ethane)(1), [(ZnCl4)(bpe) (ZnCl3N3)(bpe)](2), and [(CdCl2Br2)(bpe)] (3), were synthesized in polar organic solvents using solvent diffusion method, and the three compounds have been characterized by single-crystal X-ray diffraction and IR spectroscopy. Compound 1 comprises discrete bpe cations and centrosymmetric tetrameric anions in which cadmium(II) centers have two distinct coordination modes (four- and six-coordinated) bridged by end-on azide. The three-dimensional (3-D) organic–inorganic hybrid supramolecular structure is formed by a series of hydrogen bonds (O-H···Cl and O-H···N). Compared with compound 1, the reactants of complex 2 also include sodium azide, bpe2+ and transition metal salt except that ZnCl2 instead of CdCl2, but compound 2 is only a mononuclear complex with two different tetrahedral configuration of Zn centers. The mononuclear compound 3 crystallizes in orthorhombic system with the space grou...

NC machines are more and more widely used in manufacturing industry. As the key equipments in the factory, NC machines should be closely monitored to avoid faults. Therefore, the research on multi-function diagnosis based on BP-SOM is discussed for NC machine in the paper. Taking the precision data as the basic data for diagnosis, the research used BP and SOM algorithms to build up diagnosis models. As a result, the research has accomplished the diagnosing process and acquires good simulation output, which resembles with the real fact.

Two novel organic–inorganic hybrid supramolecular compounds based on organic cations and POMs, namely, [py]2[Hpy]3[PMo12O40]·H2O (1) and [btx]2[Mo8O26]·H2O (2) [btx = 1,6-bis(triethylmethylammonium)xylol], have been hydrothermally synthesized and characterized by single-crystal x-ray diffraction, infrared (IR) spectroscopy, and thermal gravimetric analysis (TGA). The compound 1 crystallizes in the monoclinic, space group P2(1)/c with a = 17.7932(18) A, b = 19.427(2) A, c = 15.2515(16) A, β = 98.479(2)°. Compound 2 crystallizes in the triclinic, space group P-1 with a = 11.6245(8)A, b = 11.9573(13)A, c = 12.8756(10)A, α = 63.830(6)°, β = 75.285(5)°, γ = 68.024(5)°. Compound 1 contained the classical Keggin-type discrete [PMo12O40]3− anion and 2 had the a-[Mo8O26]4− cluster. Moreover, it was indicated that these polyacid compounds had definite catalytic activities on the reaction of acetaldehyde oxidation to acetic acid.

In this article, the solution-phase reaction of metal iodides with bphx yields two novel organic-inorganic hybrid clusteric halides: [(bphx)3(Pb3I8Br4)] and [(bphx)2(Cu4I8)] (bphx = 1, 6-bis(pyridinium)hexane dication), which are characterized by X-ray crystallography and IR spectroscopy. The title trinuclear compound 1 crystallizes in Orthorhombic, space group Pccn with a = 29.077(10)A, b = 12.030(4)A, c = 19.749(7)A. Tetranuclear oligomer 2 crystallizes in Monoclinic, space group P2(1)/c with a = 10.1630(5)A, b = 15.2477(7)A, c = 15.3222(7)A. Both compounds exhibit unusual supramolecular organization wherein bphx dications reside in the channels as an efficient template. The complex 2 gives a fluorescence center at 567 nm under excitation at 450 nm, which is considered to mainly arise from the [Cu4I8]4− unit.

Two novel cation-induced complexes, {(Phen-dq) [Cu2(SCN)4]}n ( 1 ) and {(Phen-dzp) [Cu2(SCN)4]}n ( 2 ) [Phen-dq = (C14H12N2)2+, 5,6-dihydropyrazino[1, 2, 3, 4-lmn]-1, 10-phenanthrolinium, Phen-dzp = (C15H14N2)2+, 6,7-dihydro-5H-[1, 4]diazepino[1, 2, 3, 4-lmn][1,10]phenanthroline-4, 8-diium], have been synthesized via the self-assembly reaction in solution. The compound 1 possesses a two-dimensional supramolecular network linked by bridging thiocyanate groups. Complex 2 is also a two-dimensional polymeric architecture with the organic cation Phen-dzp trapped in it. Each Cu(I) atom is coordinated by two N atoms and two S atoms from four NCS groups to form a Cu2(NCS)2 rectangular dimer unit. In these two compounds, thanks to the difference from organic cations, the simple modification from Phen-dq to Phen-dzp leads to distinct structures between 1 and 2 , and these “planar” cations are effective guests to manipulate the aggregate structure of thiocyanatocuprates.