Southwest University

About: Southwest University is a education organization based out in Chongqing, China. It is known for research contribution in the topics: Gene & Population. The organization has 29772 authors who have published 27755 publications receiving 409441 citations. The organization is also known as: Southwest University in Chongqing & SWU.

The Negation of a Basic Probability Assignment

Abstract: In the field of information science, how to represent the uncertain information is still an open issue. The negation is an important way to represent the information. However, existing negation method has the limitations since it can only be applied to the probability distributions. To address this issue, this paper proposed a novel method to obtain the negation of the basic probability assignment (BPA). Moreover, several methods are used to measure the uncertainty of the BPA after each negation process, and the connection between uncertain information and entropy is discussed in this paper. Furthermore, based on the negation, this paper proposed a method to measure the uncertainty of the BPA. Finally, numerical examples are used to demonstrate the efficiency of the proposed method.

Ultrasensitive Label-Free Resonance Rayleigh Scattering Aptasensor for Hg2+ Using Hg2+-Triggered Exonuclease III-Assisted Target Recycling and Growth of G-Wires for Signal Amplification

Abstract: A novel signal-on and label-free resonance Rayleigh scattering (RRS) aptasensor was constructed for detection of Hg(2+) based on Hg(2+)-triggered Exonuclease III-assisted target recycling and growth of G-quadruplex nanowires (G-wires) for signal amplification. The hairpin DNA (H-DNA) was wisely designed with thymine-rich recognition termini and a G-quadruplex sequence in the loop and employed as a signal probe for specially recognizing trace Hg(2+) by a stable T-Hg(2+)-T structure, which automatically triggered Exonuclease III (Exo-III) digestion to recycle Hg(2+) and liberate the G-quadruplex sequence. The free G-quadruplex sequences were self-assembled into guanine nanowire (G-wire) superstructure in the presence of Mg(2+) and demonstrated by gel electrophoresis. The RRS intensity was dramatically amplified by the resultant G-wires, and the maximum RRS signal at 370 nm was linear with the logarithm of Hg(2+) concentration in the range of 50.0 pM to 500.0 nM (R = 0.9957). Selectivity experiments revealed that the as-prepared RRS sensor was specific for Hg(2+), even coexisting with high concentrations of other metal ions. This optical aptasensor was successfully applied to identify Hg(2+) in laboratory tap water and river water samples. With excellent sensitivity and selectivity, the proposed RRS aptasensor was potentially suitable for not only routine detection of Hg(2+) in environmental monitoring but also various target detection just by changing the recognition sequence of the H-DNA probe.