An ideal anti-counterfeiting technique has to be inexpensive, mass-producible, nondestructive, unclonable and convenient for authentication. Although many anti-counterfeiting technologies have been developed, very few of them fulfill all the above requirements. Here we report a non-destructive, inkjet-printable, artificial intelligence (AI)-decodable and unclonable security label. The stochastic pinning points at the three-phase contact line of the ink droplets is crucial for the successful inkjet printing of the unclonable security labels. Upon the solvent evaporation, the three-phase contact lines are pinned around the pinning points, where the quantum dots in the ink droplets deposited on, forming physically unclonable flower-like patterns. By utilizing the RGB emission quantum dots, full-color fluorescence security labels can be produced. A convenient and reliable AI-based authentication strategy is developed, allowing for the fast authentication of the covert, unclonable flower-like dot patterns with different sharpness, brightness, rotations, amplifications and the mixture of these parameters.

In vivo imaging in the second near-infrared window (NIR-II, 1000−1700 nm), which enables us to look deeply into living subjects, is producing marvelous opportunities for biomedical research and clinical applications. Very recently, there has been an upsurge of interdisciplinary studies focusing on developing versatile types of inorganic/organic fluorophores that can be used for noninvasive NIR-IIa/IIb imaging (NIR-IIa, 1300−1400 nm; NIR-IIb, 1500−1700 nm) with near-zero tissue autofluorescence and deeper tissue penetration. This review provides an overview of the reports published to date on the design, properties, molecular imaging, and theranostics of inorganic/organic NIR-IIa/IIb fluorophores. First, we summarize the design concepts of the up-to-date functional NIR-IIa/IIb biomaterials, in the order of single-walled carbon nanotubes (SWCNTs), quantum dots (QDs), rare-earthdoped nanoparticles (RENPs), and organic fluorophores (OFs). Then, these novel imaging modalities and versatile biomedical applications brought by these superior fluorescent properties are reviewed. Finally, challenges and perspectives for future clinical translation, aiming at boosting the clinical application progress of NIR-IIa and NIR-IIb imaging technology are highlighted.

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The decoding throughput during post-processing is one of the major bottlenecks that occur in a continuous-variable quantum key distribution (CV-QKD) system. In this paper, we propose a layered decoder to decode quasi-cyclic multi-edge type LDPC (QC-MET-LDPC) codes using a graphics processing unit (GPU) in continuous-variable quantum key distribution (CV-QKD) systems. As described herein, we optimize the storage methods related to the parity check matrix, merge the sub-matrices which are unrelated, and decode multiple codewords in parallel on the GPU. Simulation results demonstrate that the average decoding speed of LDPC codes with three typical code rates, i.e., 0.1, 0.05 and 0.02, is up to 64.11 Mbits/s, 48.65 Mbits/s and 39.51 Mbits/s, respectively, when decoding 128 codewords of length simultaneously without early termination.

To extract two-dimensional principal components from image samples while being insensitive to outliers, we propose a robust model for two-dimensional principal component analysis (robust 2D-PCA) by regularizing sparse penalty term. Moveover, we develop a novel iterative algorithm for robust 2D-PCA via alternating optimization, learning the projection matrices by bi-directional decomposition. To further speed up the iteration, we develop an alternating greedy approach, minimizing over the low-dimensional feature matrix and the sparse error matrix. Experimental results on dynamic background subtraction are evaluated to show the effectiveness of the proposed model, compared with conventional 2D-PCA and robust PCA algorithms.

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Modulating the excited-state intramolecular proton transfer (ESIPT) reaction to achieve anticipant performance is always fascinating for chemists. However, feasible methods and a definite mechanism for tuning the ESIPT reaction remain insufficient. In this work, we reported the feasibility of continuously modulating the ESIPT dynamics in 2-(2′-hydroxyphenyl)­oxazole (HPO) derivatives with different substitutions on the positions 5 and 5′ of the core HPO through steady-state/transient spectroscopy and theoretical calculations. We found that the main factor affecting the tendency of the ESIPT reaction is the variation of electron population on proton donor and acceptor. An index Δp dif was proposed to evaluate the overall promotion effect on proton transfer caused by the variation of electron population on proton donor and acceptor, which shows high reliability in interpreting the ESIPT tendency. This method, for its capacity to quickly estimate the tendency of ESIPT, shows great potential in ESIPT molecular design with chemical substitution of electron-donating/withdrawing moieties.