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Objective: To isolate bacteriophages with strong lytic activity against multi-drug resistant Vibrio parahaemolyticus. Methods: Using V. parahaemolyticus as host bacteria, bacteriophages were isolated and purified from seafood, and their biological characteristics and whole genome were analyzed. Results: Phage vB_VpP_3, which was isolated from crab, had a narrow host range and high host specificity with an optimal multiplicity of infection 0.1 and a maximum adsorption rate of 93%. The one-step growth curve showed that the latent period of the phage was 15 min, the average burst size was 110 PFU, and it was highly tolerant to the environment. Phage vB_VpP_3 belonged to the order Caudovirales of the family Podoviridae with a regular icosahedral head about 60 nm in diameter and a non-contractile tail about 20 nm in length. Its genome was double-stranded linear DNA with a total length of 42 459 bp and a total GC content of 46.87% without any virulence or drug resistance genes. Conclusion: Bacteriophage vB_VpP_3 was highly safe and could be used for biological control of multi-drug resistant V. parahaemolyticus.

This study is to probe into the meaning of serum miR-532-5p in nontraumatic osteonecrosis of the femoral head (ONFH), and a molecular mechanism of miR-532-5p in the development of nontraumatic ONFH. This study enrolled 96 patients diagnosed with nontraumatic ONFH and 96 patients with femoral neck fracture. The levels of miR-532-5p, ABL1, MMP-3, MMP-13, and cleaved-caspase3 were determined. Radiographic progression was assessed by ARCO staging system. Visual analog scale (VAS) and Harris hip score (HHS) were employed for evaluation of the symptomatic severity of nontraumatic ONFH. Cell viability and apoptosis in chondrocytes isolated from clinical samples were investigated with CCK-8 and flow cytometry. The levels of lactic dehydrogenase (LDH), superoxide dismutase (SOD), and malondialdehyde (MDA), mitochondrial membrane potential (ΔΨm), and reactive oxygen species (ROS) were determined. miR-532-5p was downregulated in tissues and serum of patients with nontraumatic ONFH, negatively related with ARCO staging and VAS, and positively correlated with HHS. Cell apoptosis, LDH, MDA, and ROS strengthened, while cell viability, ΔΨm, and SOD reduced in chondrocytes of nontraumatic ONFH patients. ABL1 was upregulated in cartilage tissues from nontraumatic ONFH patients. miR-532-5p targeted ABL1, and overexpressed miR-532-5p alleviated nontraumatic ONFH-induced oxidative stress damage of chondrocytes by restraining ABL1. miR-532-5p ameliorated oxidative stress injury in nontraumatic ONFH by inhibiting ABL1.

Objective To prepare monoclonal antibodies (mAbs) against human cytomegalovirus (HCMV) PP65 antigen and characterize their reactivity to HCMV PP65 antigen by immunohistochemistry. Methods The recombinant plasmid PQE30-PP65 was transformed into competent E.coli M15 cells to obtain the recombinant PP65 antigen, which was purified with Ni column affinity chromatography. BALB/c mice were immunized with the purified antigen, and the spleen cells of the mice were isolated and fused with myeloma cells (SP2/0). The mAbs were obtained by HTS screening and purified by protein A affinity chromatography, and their specificity, titer and subtype were identified by indirect ELISA. The performance of the mAbs in immunohistochemical detection of HCMV PP65 antigen was tested on slides of clinical samples. Results Eight highly specific mAbs against HCMV PP65 antigen were obtained. All these mAbs were identified to be IgG1 subtype containing κ light chains, with titers all above 1 :2 048 000. Six of the mAbs were shown to accurately identify an active infection of HCMV by slide immunohistochemistry. Conclusion We successfully prepared HCMV PP65 mAbs, and 6 of these mAbs have good reactivity with HCMV PP65 antigen in leukocytes

The vertical-objective-based ellipsometric microscope (VEM) is expected to be a useful method for clarifying the lubrication phenomena that uses thin liquid lubricants, especially the lubricant for hard disk drives (HDDs). Although the feasibility of VEM for thin lubricant films was confirmed, the designs for the optical system and image detection have not been established. In this report, the optical design of the VEM is presented, as well as the method of controlling the coherent noises and improving the thickness resolution is discussed. By our method, the thickness resolution of VEM can be improved to 0.4 nm, and the real-time observation of sub-nm-thick thin liquid lubricant films can also be achieved.

Real-time visualization of the nm-thick liquid lubricants is useful to clarify the lubrication phenomena using liquid thin films, for example, the lubrication for hard disk drives. In this paper, we present a method of measuing the film thickness using a vertical-objective-based ellipsometric microscope, which is a microscope based on ellipsometry that widely used for the investigation for thin films. In this method, the intensity signal can be directly converted to the thickness and the calibration can also be done by a phase shift method without any other devices. Sub-nm thickness and the sub-μm lateral resolutions were experimentally achieved for the visualization of the nm-thick lubricant films.

The paper propose a parallel load forecasting method based on random forest algorithm, through the analysis of historical load, temperature, wind speed and other data, the algorithm can shorten the load forecasting time and improve the processing capability of large data. This paper also designs and implements parallel load forecasting prototype system based on power user side large data of a Hadoop, including data cluster management, data management, prediction classification algorithm library and other functions. The experimental results show that the accuracy of parallel stochastic forest algorithm is obviously higher than decision tree, and the prediction accuracy on the different data sets is generally higher than decision tree, and it can better analyze and process large data.