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Avian leukosis caused by avian leukosis virus (ALV) is one of the most severe diseases endangering the poultry industry. When the eradication measures performed in commercial broilers and layers have achieved excellent results, ALV in some local chickens has gradually attracted attention. Since late 2018, following the re-outbreak of ALV-J in white feather broilers in China, AL-like symptoms also suddenly broke out in some local flocks, leading to great economic losses. In this study, a systematic epidemiological survey was carried out in eight local chicken flocks in Jiangxi Province, China, and 71 strains were finally isolated from 560 samples, with the env sequences of them being successfully sequenced. All of those new isolates belong to subgroup J but they have different molecular features and were very different from the strains that emerged in white feature broilers recently, with some strains being highly consistent with those previously isolated from commercial broilers, layers and other flocks or even isolated from USA and Russian, suggesting these local chickens have been acted as reservoirs to accumulate various ALV-J strains for a long time. More seriously, phylogenetic analysis shows that there were also many novel strains emerging and in a separate evolutionary branch, indicating several new mutated ALVs are being bred in local chickens. Besides, ALV-J strains isolated in this study can be further divided into ten groups, while there were more or fewer groups in different chickens, revealing that ALV may cross propagate in those flocks. The above analyses explain the complex background and future evolution trend of ALV-J in Chinese local chickens, providing theoretical support for the establishment of corresponding prevention and control measures.

In recent years, the avian hepatitis E virus (HEV) has been widely spread in China, causing huge economic losses. Several studies have carried out detailed epidemiologic investigations of the avian HEV, but no data were from Jiangxi province. Since early April 2020, diseases similar to hepatic rupture hemorrhage syndrome caused by the avian HEV occurred in a Roman Brown layer farm in Jiangxi province, indicating this virus may also be epidemic there. To make this assumption clear, 20 liver samples were collected from the sick flock and then analyzed by detailed viral detection, which confirmed that the avian HEV should be responsible for the aforementioned disease (6 of 20). Then, the capsid gene of the virus was sequenced to show the molecular characteristics of the strain circulating in the aforementioned flock. Sequence comparison showed that it shared 80.7 to 94.7% identities with 12 published strains, while phylogenetic analysis confirmed that it belongs to a new subtype of genotype 3. Moreover, basing on a 242 bp fragment, the novel also shared high similarities to reference strains identified as genotypes before, revealing the genotype 3 maybe very popular in China and even can be divided into several subgroups. In conclusion, a novel avian HEV strain was identified in this study, which belongs to a new subtype of genotype 3. The analysis makes up for the molecular epidemiologic data of avian HEV and provides a basis for further understanding the spread of avian HEV in China.

Aims This study aimed to investigate the antimicrobial resistance (AMR) profiles and genotypes of Streptococcus suis from Jiangxi Province, China. Methods and results A total of 314 nasal swab samples were collected from clinically healthy pigs, with a positive isolation rate of S. suis of 34·08%. Antimicrobial susceptibility testing showed that more than 80% of the isolates were susceptible to vancomycin, penicillin, minocycline and chloramphenicol. A high frequency of resistance to clindamycin, tetracycline, clarithromycin and erythromycin was observed. All of the isolates were resistant to three or more categories of antimicrobials. The erm(B) and tet(O) served as the most frequent genotypes that contributed to lincosamide, macrolide and tetracycline resistances. A part of macrolide-resistant genotypes could not exhibit specific phenotypes. Finally, integrative and conjugative elements (ICEs) were identified in 28·97% of the isolates. Conclusions The multidrug resistance of S. suis has widely emerged in Jiangxi Province. The most prevalent resistance genes and genotypes were similar to those in other regions or countries. The presence of ICEs is increasing the risk of horizontal transfer of AMR genes. Significance and impact of the study The findings could provide guidance for the rational use of antimicrobial drugs and be helpful for monitoring the AMR information of S. suis in China.

Salmonella is one of the most important foodborne pathogens associated with animal and human diseases. In this study, 672 samples of fresh meat (pork, 347; chicken, 196; and duck, 129) wer...

Bacteria of different shapes have adopted distinct mechanisms to faithfully coordinate morphogenesis and segregate their chromosomes prior to cell division. Despite recent focuses and advances, the mechanism of cell division in ovococci remains largely unknown. Streptococcus suis, a major zoonotic pathogen that causes problems in human health and in the global swine industry, is an elongated and ellipsoid bacterium that undergoes successive parallel splitting perpendicular to its long axis. Studies on cell cycle processes in this bacterium are limited. Here, we report that MsmK (multiple sugar metabolism protein K), an ATPase that contributes to the transport of multiple carbohydrates, has a novel role as a cell division protein in S. suis. MsmK can display ATPase and GTPase activities, interact with FtsZ via the N terminus of MsmK, and promote the bundling of FtsZ protofilaments in a GTP-dependent manner in vitro. Deletion of the C-terminal region or the Walker A or B motif affects the affinity between MsmK and FtsZ and decreases the ability of MsmK to promote FtsZ protofilament bundling. MsmK can form a complex with FtsZ in vivo, and its absence is not lethal but results in long chains and short, occasionally anuclear daughter cells. Superresolution microscopy revealed that the lack of MsmK in cells leads to normal septal peptidoglycan walls in mother cells but disturbed cell elongation and peripheral peptidoglycan synthesis. In summary, MsmK is a novel cell division protein that maintains cell shape and is involved in the synthesis of the peripheral cell wall. IMPORTANCE Bacterial cell division is a highly ordered process regulated in time and space and is a potential target for the development of antimicrobial drugs. Bacteria of distinct shapes depend on different cell division mechanisms, but the mechanisms used by ovococci remain largely unknown. Here, we focused on the zoonotic pathogen Streptococcus suis and identified a novel cell division protein named MsmK, which acts as an ATPase of the ATP-binding cassette-type carbohydrate transport system. MsmK has GTPase and ATPase activities. In vitro protein assays showed that MsmK interacts with FtsZ and promotes FtsZ protofilament bundling that relies on GTP. Superresolution microscopy revealed that MsmK maintains cell shape and is involved in peripheral peptidoglycan synthesis. Knowledge of the multiple functions of MsmK may broaden our understanding of known cell division processes. Further studies in this area will elucidate how bacteria can faithfully and continually multiply in a constantly changing environment.

Aims This study aimed to explore potential drug targets of Streptococcus suis at the system level. Methods and results A homologous protein mapping method was used in the construction of a protein-protein interaction (PPI) network of S. suis, which presented 1147 non-redundant interaction pairs among 286 proteins. The parameters of PPI networks were calculated and showed scale-free network properties. In all, 41 possibly essential proteins identified from 47 highly connected proteins were selected as potential drug target candidates. Of these proteins, 30 were already regarded as drug targets in other bacterial species. Six transporters with high connections to other functional proteins were identified as probably not essential but important functional proteins. Afterward, the subnetwork centred with cell division protein FtsZ was used in confirming the PPI network through bacterial two-hybrid analysis. Conclusions The predicted PPI network covers 13·04% of the proteome in S. suis. The selected 41 potential drug target candidates are conserved between S. suis and several model bacteria. Significance and impact of the study The predictions included proteins known to be drug targets, and a verifying experiment confirmed the reliability of predicted interactions. This work is the first to present systematic computational PPI data for S. suis and provides potential drug targets, which are valuable in exploring novel anti-streptococcus drugs.

The detection methods of the cavity and cavity size and pile quality of squeezed branch and disk pile are not perfect. Based on the 65 pier of a viaduct in Zhongshan City, this paper uses caliper, cross hole acoustic wave method, core pulling method and tube wave method to detect the squeezed branch and disk pile, and compares and analyzes the advantages and disadvantages, applicable conditions and detection results of each method. It can be seen from the test results that both caliper and cross hole acoustic wave method can detect the length of squeezed branch pile, while core pulling method and tube wave method can detect the quality of pile body and the thickness of sediment at the bottom of pile. The test results are basically consistent and verified with each other, and the specific data such as the length of branch and the thickness of sediment are slightly different. In this paper, caliper, cross hole acoustic method, core pulling method and tube wave method are verified and analyzed to provide ideas and support for the later detection of squeezed branch and disk pile.

Taking No.65 pier of Zhongshan-Tanzhou express line as the background, the construction technology of percussive reverse circulation drilling hole forming squeezed branch pile is studied, the construction process of percussive reverse circulation drilling hole forming squeezed branch pile is defined, and through the field trial hole forming test, the points needing attention in field construction are summarized and improved: (1) The top elevation of the steel casing shall not exceed 30cm of the surface elevation, and the hole diameter of the percussion drilling hole shall be slightly larger than the designed hole diameter, so as to avoid the floating of the steel cylinder and the influence of too small hole diameter on the squeezing operation; (2) hole cleaning operation is an important factor for the success or failure of the squeezed branch pile construction, and the sediment thickness has a great influence on the bearing capacity of the pile foundation. After the expansion equipment is squeezed and the reinforcement cage is lowered, the hole cleaning is carried out, and the control points and mud parameters during each hole cleaning are clarified; (3) during the expansion process, the extrusion pressure value and the floating amount of the expansion equipment should be detailed, the geological information should be verified, and the bearing capacity of the pile foundation should be evaluated.

Pure phase of Yb3+/Er3+ co-doped β-NaYF4 micron tubes with up-conversion fluorescence were synthesized by hydrothermal method at 180°C for 24 hours. For better utilization of sunlight and improving photocatalytic efficiency of organic dyes, TiO2 nanoparticles were modified by combining with β-NaYF4 micron tubes to form TiO2/NaYF4 composite. Three different combination methods were studied and the photocatalytic activities of the corresponding samples were tested by measuring the degradation rate of rhodamine aqueous solution under illumination of simulated sunlight. The composite that TiO2 nanoparticles were well dispersed on the surface of NaYF4 shows better photocatalytic activity than other composites and was near twice efficiency of pure TiO2 nanoparticles. The reason may be due to the high activity of heterostructure for TiO2/NaYF4 composite that will make it easy for sunlight absorption and photocatalytic degradation.

TiO2/ZnO composite thin film was prepared by sequentially spread TiO2and ZnO thin film on the ground layer by layer with sol-gel method respectively. Two different natural dyes (Hehuang safflower yellow pigment and Lycium ruthenicum Murr pigment) were used as sensitizer respectively to sensitize TiO2/ZnO thin film photoanodes and be assembled into solar cells. Dipping time of photoanodes stayed in sensitizer was investigated systematically and the results show that higher photovoltaic conversion efficiency can be obtained with extension of immersing time. The phase structure, crystallinity, morphology and optical property of photoanode were characterized based on XRD, SEM and UV-vis measurements.

The low voltage supply system’s reliability play an important role on improving equipment’s operation level and standards of management, this paper proposed a method to evaluate the reliability of low voltage supply system .The method was composed of four parts: statistical index system, definition of every index’s meaning and statistical formulas, confirming the statistical boundary conditions. In order to test the effective and practicability of the method, this paper evaluated the low voltage power supply’s reliability of BinZhou and the results are satisfactory.

The objective of this work is to examine the human response to different interventions to determine its direct intervention effect and education effect on the speeding of novice drivers. Several experiments, in which participants received different interventions when they were speeding, were conducted on the simulating driving system. The direct intervention effect of different intervention methods was measured by speed reduction and the education effect of voice intervention was measured by questionnaires. A total of 60 novice drivers and 20 experienced drivers were involved in this study, and the personality, gender and driving experience were considered in the analysis. We found that the steer wheel vibration has a significant influence on the intervention effect, but the lighting does not. The driving experience has more impact on the intervention effect of voice intervention with the Rational Style. While gender mainly influences the intervention effect of Emotional Style. The education effect of voice intervention designed with Emotional Style performs better than Rational Style. The personality from Eysenck Personality Questionnaire (EPQ) does not have a significant influence on the intervention effect. At last, a new driving style variable which can be calculated automatically from driving data was designed and the novel intervention strategy was proposed according to the research results. Our research provides a novel intervention strategy for drivers&rsquo, speeding behavior and gives an underlying insight into urban traffic safety, which is beneficial to ensure the safety, efficiency, and sustainability of the transportation system. It also serves as a reference for traffic safety research management agencies, the government, and the produced smart vehicles companies, providing guidance not limited to speeding intervention and aimed at improving other unsafe driving behavior.

The baculovirus late expression factor 11 (LEF-11) has been reported to be involved in viral DNA replication and late/very late gene activation. In this study, serial N- and C-terminal truncations of Bombyx mori nucleopolyhedrovirus (BmNPV) LEF-11 protein were fused with DsRed to investigate the nuclear localization signal by which LEF-11 enters the nucleus. Results show that 72-101 residues at the C-terminus are essential for BmNPV LEF-11 nuclear localization. Sequence alignment of this NLS from multiple LEF-11 homologs revealed high conservation in general. Site-directed mutation analysis showed that five basic residue clusters, namely, K(75)/R(76), H(81), K(83)/R(84), R(87) and K(100), were critical for the nuclear localization of BmNPV LEF-11. Co-IP analysis shows that LEF-11 binds directly to host importin α-3. Immunofluorescence analysis demonstrated that LEF-11 co-localizes with the immediate-early protein IE-1 at viral DNA replication sites in the nucleus. Further BiFC assays demonstrated the interaction of LEF-11 with LEF-3 and LEF-11 itself in the nucleus. Together, these results reveal a previous unknown mechanism for nuclear translocation of baculovirus LEF-11.

Based on the Volmer-Heyrovsky-Tafel mechanism, Frumkin adsorption and thermodynamic data of hydrogen (deuterium) adsorption in Pd, effects of surface parameters on the hydrogen (deuterium) loading ratio into Pd in the hydrogen (deuterium) evolution reaction are discussed. There is a change of mechanism from the Volmer-Tafel route to the Volmer-Heyrovsky route when the current density rises, and there exists the maximum loading ratio at a certain current density when the symmetry factor of the Heyrovsky step is less than that of the Volmer reaction. The theoretical results fit the experimental data presented before very well; other factors that affect the loading ratio are discussed as well.

The heavy metal concentrations of soil and dust samples from roadside, residential areas, parks, campus sport grounds, and commercial sites were studied in Guangzhou, South China. Heavy metals in samples were determined by inductively coupled plasma atomic emission spectrophotometer following acidic digestion with HClO(4) + HF + HNO(3). High concentrations, especially of Cd, Pb, and Zn, were found with mean concentrations of Cd, Cr, Cu, Ni, Pb, and Zn in the urban dusts being 4.22 ± 1.21, 62.2 ± 27.1, 116 ± 30, 31.9 ± 12.6, 72.6 ± 17.9, and 504 ± 191 mg/kg dry weight, respectively. The respective levels in urban soils (0.23 ± 0.19, 22.4 ± 13.8, 41.6 ± 29.4, 11.1 ± 5.3, 65.4 ± 40.2, and 277 ± 214 mg/kg dry weight, respectively), were significantly lower. The integrated pollution index of six metals varied from 0.25 to 3.4 and from 2.5 to 8.4 in urban soils and dusts, respectively, with 61 % of urban soil samples being classified as moderately to highly polluted and all dust samples being classified as highly polluted. The statistical analysis results for the urban dust showed good agreement between principal component analysis and cluster analysis, but distinctly different elemental associations and clustering patterns were observed among heavy metals in the urban soils. The results of multivariate statistic analysis indicated that Cr and Ni concentrations were mainly of natural origin, while Cd, Cu, Pb, and Zn were derived from anthropogenic activities.

Dichlorodiphenyltrichloroethane (DDT) and its main metabolites, p,p'-DDD and p,p'-DDE (DDTs in this study included DDT, DDD and DDE), are frequently detected in agricultural soils even though its usage in agriculture was banned in 1980s or earlier. In this study, eleven plants including eight maize (Zea mays) cultivars and three forage species (alfalfa, ryegrass and teosinte) widely cultivated in China were grown in the soils spiked with DDTs to investigate their potential for removal of DDT from the contaminated soils. The plants varied largely in their ability to accumulate and translocate DDTs, with the bioconcentration factor (BCF; DDT concentration ratio of the plant tissues to the soils) ranging from 0.014 to 0.25 and the translocation factor (TF; DDT concentration ratio of the shoots to the roots) varying from 0.35 (Zea mays cv Chaotian-23) to 0.76 (Zea mays spp. mexicana). The amount of DDT phytoextraction ranged from 3.89mug (ryegrass) to 27.0mug (teosinte) and accounted for

Organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) in agricultural fertilizers are new problem deserved more study. Eight kinds of organic pollutants including 43 compounds classified as US EPA priority pollutants in twenty one agricultural fertilizers which were universally used in China were determined by Gas chromatography-mass spectrum (GC-MS). Three kinds of organic pollutants including more than 5 compounds were detected in most fertilizers, composing mainly of phthalic acid esters (PAEs), nitrobenzenes (NBs) and polycyclic aromatic hydrocarbons (PAHs). There were 26 compounds detected in at least one fertilizer, five of them especially PAEs detected in most fertilizer and even in all fertilizers. Benzo(a)pyrene, a strongly carcinogenic compound was detected in two fertilizers. Higher concentrations of compounds were determined in those fertilizers such as multifunction compound fertilizers and coated fertilizers.

A novel cadmium imidazolate framework of [Cd(nim)2] (CdIF-13, nim = 2-nitroimidazolate) has been prepared and structurally characterized that demonstrates a self-penetrating 4-connected net identified with the ice XII structure of itv topology and is presented as the first metal–organic framework (MOF) with itv topology and the second metal imidazolate framework (MIF) with self-penetrating and ice-like structure.

By modulating the synthetic strategy based on changing substituents on the ligand and solvent used in the synthesis, a series of metal organic frameworks (MOFs) of two chiral binaphthol-like ligands of 4-(1H-imidaozol-1-yl)benzoic acid (HIBA) and 4-(1H-2-methylimidazol-1-yl)benzoic acid (HMIBA) with various interpenetrating topologies have been synthesized under solvothermal conditions: Zn(IBA)2 (1), Co(IBA)2 (2), Cd(IBA)2·H2O·1.7DMF (3), Cd(MIBA)2·H2O·1.3DMF (4), Co(MIBA)2·H2O·1.3DMF (5) and Cd(MIBA)2·0.5H2O·1.2DMA (6) (DMF = N,N-dimethylformamide and DMA = N,N′-dimethylacetamide). X-ray diffraction study reveals that compounds 1 and 2 crystallize in tetragonal crystal system with chiral space groupsP4122 and P4322, respectively, indicating that they are a pair of structural enantiomers, having a twofold interpenetrating (4,4)-net. Compound 3 crystallizes in orthorhombic crystal system and non-centrosymmetric space group Pca21, which can be defined as an abnormal fourfold [2 + 2] interpenetrating diamond net. The isostructural compounds 4 and 5 crystallize in tetragonal crystal system and space group P4212, representing a chiral structure and a normal mode of fourfold interpenetrating diamondoid net. Compound 6 crystallizes in non-centrosymmetric space group Aba2 and exhibits a normal mode of fourfold diamondoid interpenetrating net.