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Plasmonic metasurfaces have been widely used in biosensing to improve the interaction between light and biomolecules through the effects of near-field confinement. When paired with biofunctionalization, plasmonic metasurface sensing is considered as a viable strategy for improving biomarker detection technologies. In this review, we enumerate the fundamental mechanism of plasmonic metasurfaces sensing and present their detection in human tumors and COVID-19. The advantages of rapid sampling, streamlined processes, high sensitivity, and easy accessibility are highlighted compared with traditional detection techniques. This review is looking forward to assisting scientists in advancing research and developing a new generation of multifunctional biosensors.

Mid-infrared absorption spectroscopy is a powerful tool to identify analytes by detecting their material fingerprint in a label-free way, but it faces barriers on trace-amount analysis due to the difficulties in enhancing the broadband spectral signals. Here, we propose a sensing scheme based on the angular scanning of polarized light on a dielectric metagrating, and demonstrate it by numerical simulation. This approach not only indicates a series of significant signal enhancement factors over 30 times in an ultra-wide mid-infrared band, but also enables the explicit identification for various analytes, including 2D materials and trace-amount thin film samples. Our method would facilitate mid-infrared sensing for 2D materials and trace-amount analysis, and enable many new applications on non-destructive molecular identification.

Terahertz (THz) sensing of molecular fingerprint enables wide applications in biomedicine and security detection. Conventional detection approaches face big barriers in trace analysis of analyte due to the difficulties of enhancing the broadband molecular absorption. In order to achieve strong broadband wave–matter interaction for the analyte, we propose a method based on THz wave angular scanning on a dielectric metagrating. In virtue of the guided-mode resonance, one can strengthen the local electric field in various trace-amount analytes by tuning the polarization and incident angle, which leads to significant enhancement on the broadband signal of molecular fingerprint. The study paves the way for more applications of THz trace-amount detection.

Improving the user peak rate in hot-spots is one of the original intention of design for 5G networks. The cell radius shall be reduced to admit less users in a single cell with the given cell peak rate, namely Hyper-Dense Networks (HDN). Therefore, the feature extraction of the node trajectories will greatly facilitate the development of optimal algorithms for radio resource management in HDN. This paper presents a data mining of the raw GPS trajectories from the urban operating vehicles in the city of Shenzhen. As the widely recognized three features of human traces, the self-similarity, hot-spots and long-tails are evaluated. Mining results show that the vehicles to serve the daily trip of human in the city always take a short travel and activate in several hot-spots, but roaming randomly. However, the vehicles to serve the goods are showing the opposite characteristics.

Aluminum has recently attracted significant interest as a promising alternative material to noble metals for plasmonic metasurface biosensing, but it suffers from surface oxidation and higher visible-light loss, which is usually believed to limit its capability of sensing. We report here that the large-area flexible passivated Al nanopillar metasurface shows better bulk and surface sensing performance than Au nanopillar metasurface. Compared to the Au metasurface, the existance of superficial alumina layer protects the Al metasurface from further oxidation and maintains the high surface sensitivity. In the test for the antibody of bovine serum albumin, the Al-based metasurface demonstrates a much higher sensitivity by two orders of magnitude versus the Au counterpart. Its detection of limit is as low as 1 pg/mL, which implies a great potential for clinical diagnosis. Our study paves the way for the use of Al metasurface in low-cost high-performance biosensing of mobile healthcare.

Oriental river prawn (Macrobrachium nipponense) is one of the most important freshwater prawns for aquaculture in China. However,M. nipponense farming recently declined due to genetic retrogression. Its genetic diversity of different populations in the Yangtze River with microsatellite markers was investgated in order to give support to conservation and utilization of wild resources of M. nipponense. Twenty polymorphic microsatellite markers were applied to investigate the genetic diversity of 6 M. nipponense populations in the Yangtze River. The sampling sites included Chongqing,Wanzhou,Yichang,Wuhan,Jiujiang and Jiangyin. The average number of alleles (A) and effective numbers of alleles (Ne) in 6 populations were 5.25 and 3.462 2 respectively. The mean PIC value of 20 microsatellite loci was 0.589 4. Expected heterozygosity (He) of 6 populations was as follows:Jiangyin (0.630 8),Jiujiang (0.609 6),Yichang (0.594 5),Wuhan (0.593 4),Wanzhou (0.584 4) and Chongqing (0.582 1),and their mean value was 0.629 6. The analysis of molecular variance (AMOVA) indicated that almost majority of the variance in the M. nipponense was within populations (93.08%) ,and 6.92%was among populations. The FST values between populations were 0.025 3-0.083 8(P0.05),which showed the genetic divergence between populations in the Yangtze River was intermediate but lower than that in the lakes. It was probably because running water promoted the exchanges between populations. Hardy-Weinberg equilibrium analysis indicated that deficiency of heterozygote existed in all of 6 populations,which was probably because of rare allele deficiency or null alleles. The genetic distances among populations ranged from 0.062 0 to 0.180 9. The UPGMA tree showed that Jiangyin stock formed an independent clade and resident 5 populations formed another one in which Jiujiang and Wuhan populations clustered at first.