Determination of the mimic epitope of the M-like protein adhesin in swine Streptococcus equi subsp. zooepidemicus

<p>Abstract</p> <p>Background</p> <p>The M-like protein, also known as SzP, is expressed on the surface of <it>Streptococcus equi </it>subsp. z<it>ooepidemicus </it>(<it>S</it>. z<it>ooepidemicus</it>). Previous studies demonstrated that SzP is similar to M protein of group A <it>Streptococcus </it>in the structure and characteristics of antiphagocytosis. The M protein is an adhesin that can bind to the host cells, however it is not known whether the SzP of <it>S</it>. z<it>ooepidemicus </it>also functions as an adhesin. We conducted an investigation to determine SzP as an adhesin, and one SzP epitope was identified to be responsible for mediating binding to HEp-2 cells.</p> <p>Methods</p> <p>The gene encoding SzP was expressed in <it>E. coli</it>, and the purified recombinant SzP (rSzP) was recognized by rabbit anti-<it>S</it>. z<it>ooepidemicus </it>antibodies using immunoblot. Furthermore, the adherence of <it>S</it>. z<it>ooepidemicus </it>to HEp-2 cells was inhibited by anti-rSzP antibodies in a dose-dependent manner. We employed a random 12-peptide phage display library for screening of immunodominant mimics of the SzP, which were recognized by an anti-SzP specific monoclonal antibody (mAb 2C8). Initial positive phage clones were identified by ELISA, followed by assays to determine the adherence-inhibiting ability of the peptide.</p> <p>Results</p> <p>Ten out of fourteen selected positive clones showed high reactivity that effectively inhibited the binding of mAb 2C8 to rSzP. The motif XSLSRX was highly conserved among six of the ten clones.</p> <p>Conclusion</p> <p>Collectively, our findings suggest that the motif XSLSRX may represent an immunodominant mimic epitope of the SzP of <it>S</it>. z<it>ooepidemicus </it>strain ATCC 35246, and that the same epitope may be used to mediate SzP binding to HEp-2 cells.</p

Graphic Style Transfer Technology in Multimedia Communication: An Application of Deep Residual Adaptive Networks in Graphic Design

With the rapid development of wireless network technology and the rapid popularity of portable smart terminals, multimedia communication based on images and videos has become the favorite way of communication in the new era. Image style transfer technology is one of the research directions that has attracted much attention in the field of multimedia communication. To achieve the diversification of images and ease of use in the multimedia communication process, this paper researches the multimedia network communication technology and image style transfer technology. By combining visual style transfer technology and depth residual adaptive network technology in multimedia communication technology, the redesign and creation of graphics can be carried out effectively. The resulting graphics can meet the needs of the art creators and the technique provides higher creative efficiency, excellent peak model signal-to-noise ratio and structural similarity performance, and output levels that meet the basic needs compared to traditional manual design. The method can be effectively used in urban building appearance design and art creation and has good theoretical and practical research value

Study on the Structure Optimization and the Operation Scheme Design of a Double-Tube Once-Through Steam Generator

AbstractA double-tube once-through steam generator (DOTSG) consisting of an outer straight tube and an inner helical tube is studied in this work. First, the structure of the DOTSG is optimized by considering two different objective functions. The tube length and the total pressure drop are considered as the first and second objective functions, respectively. Because the DOTSG is divided into the subcooled, boiling, and superheated sections according to the different secondary fluid states, the pitches in the three sections are defined as the optimization variables. A multi-objective optimization model is established and solved by particle swarm optimization. The optimization pitch is small in the subcooled region and superheated region, and large in the boiling region. Considering the availability of the optimum structure at power levels below 100% full power, we propose a new operating scheme that can fix the boundaries between the three heat-transfer sections. The operation scheme is proposed on the basis of data for full power, and the operation parameters are calculated at low power level. The primary inlet and outlet temperatures, as well as flow rate and secondary outlet temperature are changed according to the operation procedure

The shale revolution, geopolitical risk, and oil price volatility

The U.S. shale revolution, using new technologies to extract crude oil, has led to new dynamics in the supply side of the global oil market. We ask whether the shale revolution has dampened the role of geopolitical risk in oil price volatility. We extend a reduced form Structural Break Threshold Vector Autoregressive (SBT-VAR) model to a structural SBT- VAR model and identify the structural innovations by allowing conditional heteroskedasticity. Compared with the conventional reduced form VAR and TVAR models, an SBT-VAR with a constant threshold and a break in April 2014 are supported by the data. We then analyse the conditional (co)variance impulse response concerning two distinct shock scenarios, one with only a geopolitical risk shock, and the other with a simultaneous shale production shock and a geopolitical risk shock. The volatility responses are due to the identified contemporaneous relationships amongst geopolitical risk, shale production and oil prices, and are conditional on volatilities at the points in time. With the extra unit shale production shock, we find that the volatility response of oil prices to a geopolitical risk shock is higher, but the response is less correlated with the geopolitical risk factor

Exponentially weighted particle filter for simultaneous localization and mapping based on magnetic field measurements

This paper presents a simultaneous localization and mapping (SLAM) method that utilizes the measurement of ambient magnetic fields present in all indoor environments. In this paper, an improved exponentially weighted particle filter was proposed to estimate the pose distribution of the object and a Kriging interpolation method was introduced to update the map of the magnetic fields. The performance and effectiveness of the proposed algorithms were evaluated by simulations on MATLAB based on a map with magnetic fields measured manually in an indoor environment and also by tests on the mobile devices in the same area. From the tests, two interesting phenomena have been discovered; one is the shift of location estimation after sharp turning and the other is the accumulated errors. While the latter has been confirmed and investigated by a few researchers, the reason for the first one still remains unknown. The tests also confirm that the interpolated map by using the proposed method improves the localization accuracy

Delving into E-Commerce Product Retrieval with Vision-Language Pre-training

E-commerce search engines comprise a retrieval phase and a ranking phase, where the first one returns a candidate product set given user queries. Recently, vision-language pre-training, combining textual information with visual clues, has been popular in the application of retrieval tasks. In this paper, we propose a novel V+L pre-training method to solve the retrieval problem in Taobao Search. We design a visual pre-training task based on contrastive learning, outperforming common regression-based visual pre-training tasks. In addition, we adopt two negative sampling schemes, tailored for the large-scale retrieval task. Besides, we introduce the details of the online deployment of our proposed method in real-world situations. Extensive offline/online experiments demonstrate the superior performance of our method on the retrieval task. Our proposed method is employed as one retrieval channel of Taobao Search and serves hundreds of millions of users in real time.Comment: 5 pages, 4 figures, accepted to SIRIP 202