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In this study, polypyrrole/silver (PPy/Ag) conductive polyester fabric was synthesized via an in-situ polymerization method under UV exposure, using silver nitrate (AgNO3) as an oxidizing agent in the presence of sodium dodecyl benzene sulfonate (SDBS) and polyvinylpyrrolidone (PVP). The effect of the preparation processes on the properties of the conductive fabric was studied experimentally, and the optimal preparation process of the conductive fabric was obtained. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) showed the chemical structural properties of the PPy/Ag conductive polyester fabric. X-ray diffraction (XRD) confirmed the presence of silver nanoparticles in the prepared material. Furthermore, subsequent test results proved that the PPy/Ag conductive polyester fabric prepared by UV irradiation had good electrical conductivity and antibacterial property. The sheet resistance of the prepared conductive fabric was 61.54 Ω • sq−1.

Melt‐spun poly(trimethylene terephthalate) (PTT) and polyamide 56 (PA56) fibers are generally prepared individually. Herein, inspired by the complementary properties of these two materials, PTT/PA56 blend fibers were prepared by two‐step melt spinning and drawing processes. The regularity of crystalline regions, overall orientation in crystalline and amorphous regions, and dimensional stability under hot and humid conditions can be improved by increasing drawing temperature. The most suitable drawing temperature is 90°C, at which 4‐fold drawn PTT and PA56 fibers show tenacity of 2.94 and 3.54 cN/dtex, respectively. An increase in draw ratio leads to increase in the order of crystal regions and overall orientation in crystalline and amorphous phases. Interestingly, increasing dispersed phase content from 0 to 10 wt% is conducive to the increase in tenacity of samples. The PTT/PA56 (10/90) blend fiber suggests the maximum tenacity value, and tenacity of 4‐fold drawn fiber is 4.02 cN/dtex. As PA56 content increases, dimensional stability of samples under dry conditions increases. Comprehensive analysis demonstrates that the PTT/PA56 (10/90) blend fiber achieves the best combination of tensile properties and dimensional stability. The prepared PTT/PA56 blend fibers are potentially competitive in the fields of fibers, garment, and decoration due to their satisfactory comprehensive performances. [ABSTRACT FROM AUTHOR]

Tularemia is a disease caused by distinct subspecies and phylogenetic groups within the bacterial species Francisella tularensis (1,2). These groups exhibit distinct phylogeographic patterns; F. tularensis subsp. tularensis (type A) [...]

Abstract Background Yersinia pestis, the aetiological agent of plague, has been well defined genotypically on local and worldwide scales. In November 2005, five cases of severe pneumonia of unknown causes, resulting in two deaths, were reported in Yulong, Yunnan province. In this study, we compared Y. pestis isolated from the Yulong focus to strains from other areas. Results Two hundred and thirteen Y. pestis strains collected from different plague foci in China and a live attenuated vaccine strain of Y. pestis (EV76) were genotyped using multiple-locus variable-number tandem repeat analysis (MLVA) on 14 loci. A total of 214 Y. pestis strains were divided into 85 MLVA types, and Nei's genetic diversity indices of the various loci ranged between 0.02 - 0.76. Minimum spanning tree analysis showed that Y. pestis in China could be divided into six complexes. It was observed that Microtus strains were different from the other three biovar strains. Each plague focus had its own unique MLVA types. Conclusion The strains isolated from Yulong, Yunnan province had a unique MLVA type, indicating a new clone group. Our results suggest that Yulong strains may have a close relationship with strains from the Qinghai-Tibet Plateau plague focus.

Yersinia pestis, the causative agent of plague, is a deadly bacterium that affects humans. Strain D106004 was isolated from a new plague focus in Yulong County, China, in 2006. To gain insights into the epidemic origin, we have sequenced the genomes of D106004 and strains Z176003 and D182038, isolated from neighboring regions. doi: 10.1128/JB.00340-10

Abstract: Objective: To study the types of subspecies of Francisella tularensis from China and to investigate the genetic relationships between F. tularensis strains from China and from other countries. Methods: Ten strains of F. tularensis isolated from China were amplified by using typing primers C1/C4 and RD1. On the basis of the lengths of the polymerase chain reaction (PCR) products, it was concluded that these strains of F. tularensis belonged to the same subspecies. At the same time, the fopA, tul4, and 16S rRNA genes of the 10 strains were amplified, and a three-gene based phylogenetic analysis was performed using the Molecular Evolutionary Genetics Analysis software version 4.0. Results: The 10 strains of F. tularensis from China were all identified as belonging to subspecies holarctica (type B). We found no direct relationship between the genotypes of F. tularensis subsp. holarctica and the geographical area from where they were isolated. Conclusion: The F. tularensis strains isolated from North China mainly belong to subspecies holarctica (type B). The strains of F. tularensis subsp. holarctica from China may have evolved earlier than those from Europe and North America. [Copyright &y& Elsevier]

Objective: This study aims to develop a strategy for distinguishing Yersinia pestis of the Xilingele Plateau ecotype from other biovar of Yersinia pestis using insertion sequences., Methods: Genome computational analysis was used to discover the positions of insertion sequences unique to Yersinia pestis 91001. PCR was used to confirm that these positions were exclusively present in the Xilingele Plateau ecotype of Yersinia pestis , while it was absent in other Yersinia species., Results: It was validated that the amplicons of IS100-45-1 IS100-51-1, IS285-40 and IS285-41 were exclusive to Yersinia pestis of the Xilingele Plateau ecotype., Conclusions: Insertion sequences could be reliable candidate biomarkers for Yersinia pestis strains of Xilingele Plateau ecotype. We can differentiate Yersinia pestis strains of Xilingele Plateau ecotype from other Yersinia pestis using simple PCR methods., (© 2019 by the Association of Clinical Scientists, Inc.)

Objective: To establish a gene identification method of Yersinia pestis and Yersinia pseudotuberculosis for plague surveillance., Methods: According to the specific genomic sequences of Y. pestis and Y. pseudotuberculosis, i.e. "pestis Island (PeI)" and "pseudotuberculosis Island (PsI)" and the published genomic sequences of 12 strains of Y. pestis and 4 strains of Y. pseudotuberculosis, the specific identification primers of these sequences were designed., Results: A total of 52 strains of Y. pestis and 57 strains of Y. pseudotuberculosis and other intestinal bacteria strains were tested with PCR. Of the 5 pairs of Y. pestis identification primers, PeI2 and PeI11 were specific for Y. pestis. Besides Y. pestis, the primers PeI1, PeI3 and PeI12 could detect part of 57 Y. pseudotuberculosis strains. Of the 5 pairs of Y. pseudotuberculosis identification primers, PsI1 could detect all the 52 strains of Y. pestis and 57 strains of Y. pseudotuberculosis. PsI7, PsI16, PsI18 and PsI19 were specific for Y. pseudotuberculosis., Conclusion: The primers PsI1, PeI 2 and PeI11, PsI7, PsI16, PsI18 and PsI19 can be used in the rapid identification of Y. pestis and Y. pseudotuberculosis, which can be also used to explore the circulation of atypical Y. pestis in quiescent plague foci.

Background: Yersinia pestis, the aetiological agent of plague, has been well defined genotypically on local and worldwide scales. In November 2005, five cases of severe pneumonia of unknown causes, resulting in two deaths, were reported in Yulong, Yunnan province. In this study, we compared Y. pestis isolated from the Yulong focus to strains from other areas., Results: Two hundred and thirteen Y. pestis strains collected from different plague foci in China and a live attenuated vaccine strain of Y. pestis (EV76) were genotyped using multiple-locus variable-number tandem repeat analysis (MLVA) on 14 loci. A total of 214 Y. pestis strains were divided into 85 MLVA types, and Nei's genetic diversity indices of the various loci ranged between 0.02 - 0.76. Minimum spanning tree analysis showed that Y. pestis in China could be divided into six complexes. It was observed that Microtus strains were different from the other three biovar strains. Each plague focus had its own unique MLVA types., Conclusion: The strains isolated from Yulong, Yunnan province had a unique MLVA type, indicating a new clone group. Our results suggest that Yulong strains may have a close relationship with strains from the Qinghai-Tibet Plateau plague focus.

Specific immunoglobulin G antibody for severe acute respiratory syndrome (SARS) coronavirus was detected in maternal blood, umbilical blood, and amniotic fluid from a pregnant SARS patient. Potential protection of fetus from infection was suggested.

Objective: To evaluate the significance of traditional index on the identification of Bacillus anthracis and its correlation with pathogenic strains., Methods: Routine bacteriologic methods and PCR of virulence genes were used to determine the difference on traditional identification index between pathogenic and nonpathogenic Bacillus., Results: The characteristics of colony, with hemolysis and mobility both negative are the important interrelated characters of pathogenic strains of Bacillus anthracis., Conclusion: To judge the risk of anthrax, virulence of genes must be first defined. Some traditional methods for identification are still useful when molecular biological methods are not available.