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Ferrograph-based wear debris analysis (WDA) provides significant information for wear fault analysis of mechanical equipment. After decades of offline application, this conventional technology is being driven by the online ferrograph sensor for real-time wear state monitoring. However, online ferrography has been greatly limited by the low imaging quality and segmentation accuracy of particle chains when analyzing degraded lubricant oils in practical applications. To address this issue, an integrated optimization method is developed that focuses on two aspects: the structural re-design of the online ferrograph sensor and the intelligent segmentation of particle chains. For enhancing the imaging quality of wear particles, the magnetic pole of the online ferrograph sensor is optimized to enable the imaging system directly observe wear particles without penetrating oils. Furthermore, a light source simulation model is established based on the light intensity distribution theory, and the LED installation parameters are determined for particle illumination uniformity in the online ferrograph sensor. On this basis, a Mask-RCNN-based segmentation model of particle chains is constructed by specifically establishing the region of interest (ROI) generation layer and the ROI align layer for the irregular particle morphology. With these measures, a new online ferrograph sensor is designed to enhance the image acquisition and information extraction of wear particles. For verification, the developed sensor is tested to collect particle images from different degraded oils, and the images are further handled with the Mask-RCNN-based model for particle feature extraction. Experimental results reveal that the optimized online ferrography can capture clear particle images even in highly-degraded lubricant oils, and the illumination uniformity reaches 90% in its imaging field. Most importantly, the statistical accuracy of wear particles has been improved from 67.2% to 94.1%.

The attapulgite / natural rubber (NR) micro-nano composites were prepared by co-coagulating rubber latex and clay aqueous suspension. The vulcanization behavior, mechanical properties and microcosmic structure of the composites were investigated. The field emission scanning electron microscope (FESEM) micrographs of the composites showed that the attapulgite stick particles inserted into the rubber. The interaction between the attapulgite and natural rubber could be improved by using the attapulgite pre-modified with cetyltrimethylammonium bromide (CTAB). The properties of the composites filled with CTAB-modified attapulgite are better than that of the composites filled with carbon black N330. The best properties, which the tensile strength, the 300% tensile modulus and the tear strength increase by 46.9%, 269.7%, 102.0%, respectively, compared with the composites with the unmodified attapulgite, can be obtained, when 20 phr CTAB-modified attapulgite was added.

We recently identified a novel plasmid-mediated resistance-nodulation-division (RND)-type efflux pump gene cluster, tmexCD1-toprJ1, in Klebsiella pneumoniaethat conferred resistance to multiple antimicrobials, including tigecycline. While homologs of tmexCD1-toprJ1were found encoded in many other bacterial species in GenBank, their functions and transfer mechanisms remain unknown.

In an era of increasing concerns about antimicrobial resistance, tigecycline is likely to have a critically important role in the treatment of carbapenem-resistant Enterobacteriaceae, the most problematic pathogens in human clinical settings—especially carbapenem-resistant K.pneumoniae. Here, we identified a new plasmid-borne RND-type tigecycline resistance determinant, TMexCD1-TOprJ1, which is widespread among K. pneumoniaeisolates from food animals. tmexCD1-toprJ1appears to have originated from the chromosome of a Pseudomonasspecies and may have been transferred onto plasmids by adjacent site-specific integrases. Although tmexCD1-toprJ1still appears to be rare in human clinical isolates, considering the transferability of the tmexCD1-toprJ1gene cluster and the broad substrate spectrum of TMexCD1-TOprJ1, further dissemination of this mobile tigecycline resistance determinant is possible. Therefore, from a “One Health” perspective, measures are urgently needed to monitor and control its further spread. The current low prevalence in human clinical isolates provides a precious time window to design and implement measures to tackle this.

The presence and molecular characteristics of carbapenemase-producing Enterobacteriaceae(CPE) among meat products in China were investigated. A total of 110 carbapenem-resistant Enterobacteriaceae(CRE) isolates, including 94 Escherichia coliand 10 Klebsiella pneumoniaeisolates, were identified from 105 of 794 (13.2%) samples. The positive rates markedly increased from 2016 (9.4%) to 2018 (22.2%). Only blaNDMgenes were detected; 79.1% of blaNDMgenes were carried by IncX3 plasmids.