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Optical vortices (OVs), as eigenmodes of optical orbital angular momentum, have been widely used in particle micro-manipulation. Recently, perfect optical vortices (POVs), a subclass of OVs, are gaining increasing interest and becoming an indispensable tool in optical trapping due to their unique property of topological charge-independent vortex radius. Here, we expand the concept of POVs by proposing concentric ring optical traps (CROTs) and apply them to trapping and rotating particles. A CROT consists of a series of concentric rings, each being a vortex whose radius and topological charge can be controlled independently with respect to the other rings. Quantitative results show that the generated CROTs have weak sidelobes, good uniformity, and relatively high diffraction efficiency. In experiments, CROTs are observed to trap multiple dielectric particles simultaneously on different rings and rotate these particles with the direction and speed of rotation depending on the topological charge sign and value of each individual ring. In addition, gold particles are observed to be trapped and rotate in the dark region between two bright rings. As a novel tool, CROTs may find potential applications in fields like optical manipulation and microfluidic viscosity measurements.

This paper introduces the latest research on the application of the new dynamic network DEA method in the measurement of the operating efficiency of the banking industry, and measures the operating efficiency of 15 listed banks in China by using the directional distance function (DDF) and the new dynamic network DEA model combined with the Malmquist index. To effectively evaluate the impact of uncertain financial risks on the operating efficiency of banks, we respectively selected the measurement indicators of total assets, number of employees, deposits, and net profit to calculate the operating efficiency of banks in the process of medium and long-term investment. According to the actual situation of bank operation, the process of bank operation is divided into the input stage of capital and manpower, the profit stage of capital operation, and operation stage, and a two-stage DEA network model is constructed. By measuring the overall operating efficiency of China's 15 banks from 2017 to 2022, the results show that the new dynamic network DEA model can better distinguish the efficiency of China's banks from the single-stage DEA model. In the new dynamic network model, the total factor productivity of most banks in China is reduced to varying degrees, which is greatly affected by pure technical efficiency.

The nature of rigidity and low energy density of polypyrrole (PPy)‐based electrodes limits their wide application in flexible energy storage devices. In this study, reduced graphene oxide (rGO) wrapped polypyrrole (PPy)/oxidized carbon cloth (OCC) (rGO@PPy/OCC) is prepared by the polymerization of pyrrole using MnO2 as the oxidant on the surface of OCC followed by the adsorption and reduction of graphene oxide (GO). The prepared rGO@PPy/OCC electrode exhibits a high gravimetric specific capacitance of 547 F g−1 at a current density of 0.5 A g−1 and a high area specific capacitance of 1641 mF cm−2 at a current density of 1.5 mA cm−2. It nearly maintains the initial capacitance after 8000 cycles at a high scan rate of 200 mV s−1 and at a large current density of 10 A g−1. Moreover, the flexible rGO@PPy/OCC electrodes are used to construct flexible solid‐state supercapacitors (FSSC). The FSSC based on rGO@PPy/OCC exhibits a high energy density (33.89 Wh kg−1 and 101.81 µWh cm−2) and a capacitance retention of 95.10% after 1000 bending cycles, demonstrating the excellent cycling stability and flexibility. Therefore, it is potential for rGO@PPy/OCC as a flexible electrode to fabricate high‐performance FSSC. [ABSTRACT FROM AUTHOR]

Guide star assisted wavefront shaping techniques have been exploited for focusing and imaging through turbid media by addressing a scatter inverse pattern. However, the turbid medium is required to be steady before finding the proper correction pattern, which limits applications in focusing and imaging through dynamic media, such as turbid water or blood. This study proposes a holography-based dual-polarization computational wavefront shaping method for imaging objects at variant depths behind dynamic turbid media. The orthogonal polarized output speckles of a point source (considered as a guide star) and an object are simultaneously recorded in holograms in separate regions of a single CCD camera. The holograms of the point source and object are subjected to the same distortion regardless of whether the media is static or dynamic. The hologram of the point source is used to determine the correction phase pattern for the distortion, while that of the object is used to record the complex scattered wavefront of the object. To reconstruct a clear object image, the wavefront of the scattered object is digitally corrected using the correction phase pattern and is then transferred to the image plane by calculating the transmission of the angular spectrum. Benefiting from the autofocusing feature of digital holography, objects at different depths can be recovered from a single shot hologram pair. The potential applications of the proposed method in diverse dynamic scattering media are demonstrated by imaging through a moving diffuser, turbid water, and pig blood with optical depth beyond 10. [ABSTRACT FROM AUTHOR]

Constructing a multi-dimensional education and teaching quality evaluation system is the key content of China’s higher education reform. In order to establish a quality evaluation system suitable for the portfolio assessment, we take the construction of “new engineering” and the certification goal of engineering education as the guiding ideology, taking the VALUE rubrics as the reference system and taking the cell engineering course as the object. The course assessment and evaluation structure and course assessment standards are reconstructed and refined, and a complete cell engineering course quality evaluation system suitable for portfolio assessment was constructed. The establishment of this course quality evaluation system can provide reference for the construction of other professional course quality evaluation systems of the same nature in colleges and universities. [ABSTRACT FROM AUTHOR]

Background: Although the roles of PD-L1 in promoting tumor escape from immunosurveillance have been extensively addressed, its non-immune effects on tumor cells remain unclear., Methods: The spatial heterogeneity of PD-L1 staining in human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) tissues was identified by immunohistochemistry. Three-dimensional (3D) specific cell-led invasion assay and 3D cancer spheroid model were used to investigate the roles of PD-L1 hi leader cells in collective invasion. The impact of M1 macrophages on specific PD-L1 expression in leader cells and its mechanisms were further studied. Finally, the effect of combination therapy of anti-PD-L1 and CDK4 inhibitor on HPV-positive tumors were evaluated on a mice model., Results: Here, we observed a distinctive marginal pattern of PD-L1 expression in HPV-positive HNSCC tissues. By mimicking this spatial pattern of PD-L1 expression in the 3D invasion assay, we found that PD-L1 hi cells led the tumor collective invasion. M1 macrophages induced specific PD-L1 expression in leader cells, and depletion of macrophages in tumor-bearing mice abrogated PD-L1 hi leader cells and collective invasion. Mechanistically, TNF-α secreted by M1 macrophages markedly increased the abundance of PD-L1 via CDK4/ubiquitin-specific peptidase 14-mediated deubiquitination of PD-L1. We also found that suppression of CDK4 enhanced the efficacy of anti-PD-L1 therapy in an E6/E7 murine model., Conclusions: Our study identified TNF-α/CDK4/ubiquitin-specific peptidase 14-mediated PD-L1 stability as a novel mechanism underlying M1 macrophage-induced PD-L1 hi leader cells and collective tumor invasion, and highlighted the potential of the combination therapy of anti-PD-L1 and CDK4 inhibitor for HPV-positive HNSCC., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

In order to improve the teaching quality of engineering courses, we introduced a multi-dimensional teaching method into the teaching reform of biology majors in colleges based on the portfolio assessment in the curriculum of Cell Engineering. We reformed the knowledge system, teaching form and implementation scheme of this course. By combining the reform of online teaching, interactive teaching, case teaching and other teaching modes, the students mastered the relevant professional knowledge and the scientific and technological frontier of Cell Engineering. Moreover, their learning interest and enthusiasm, ability of analyzing and solving professional problems related to Cell Engineering also improved. The implementation of teaching reform of this course provides a reference for other similar professional courses in colleges.