Rapid and simultaneous visual typing of high-risk HPV-16/18 with use of integrated lateral flow strip platform.

A biosensor for rapid and simultaneous visual identification of high-risk human papillomavirus (HPV) genotypes 16 and 18 in clinical samples based on polymerase chain reaction (PCR) integrated lateral flow strip platform was developed. Using an one-step protocol to extract nucleic acid rapidly and the functionalized primer sets specific to HPV-16 and 18 were designed for the simultaneous amplification. In the presence of target HPV genotypes, the corresponding functionalized primer sets will participate in the PCR process and produce numerous duplex functionalized dsDNA amplicons. With the bridge effect of duplex functionalized dsDNA amplicons between gold nanoparticles-fluorescein isothiocyanate antibody conjugates (AuNP-FITC antibody conjugates) and other two antibodies on corresponding test line (T1 or T2), visualized color signals on test lines could be obtained directly visible with a naked eye. Combining the high amplification efficiency of PCR and the visualized sensing of LFS, as low as 700 copies of HPV-16 and 18 DNA were detected simultaneously within 75 min, which can promote application in the resource limited settings. High-risk genotypes of HPV-16 and HPV-18 were easily and simultaneously screened with the amplification-assisted molecular lateral flow strip by on-site observation in the resource-limited settings.

Effect of the Addition of Steel Fibers on the Bonding Interface and Tensile Properties of Explosion-Welded 2A12 Aluminum Alloy and SS-304 Steel.

First of all, the explosion-welding method was adopted to prepare steel fiber-reinforced steel-aluminum composite plates. Secondly, the smooth particle hydrodynamic (SPH) method was used to investigate the effect of introducing steel fibers to a vortex region created at the bonding interface of the steel-aluminum composite plate. Thirdly, the following conclusions were drawn through an analysis of the vortex region with the assistance of scanning electron microscopy and energy-dispersive X-ray spectroscopy. A brittle intermetallic compound FeAl was produced in the vortex region in an environment characterized by high temperature, high pressure, and high strain rate, resulting in cracks, holes and pores. In addition, the hardness of the vortex area was less than the estimated value, which is mainly because the main element in the vortex area was 2A12 aluminum with low hardness, and there were cracks, holes, pores and other defects that caused hardness reduction. Although the addition of steel fibers caused defects at the bond interface, the addition of steel fibers was effective in improving the tensile resistance performance of steel-aluminum composite panels to a certain extent. In addition, the larger the fiber diameter, the more significant the increase in tensile resistance.