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Emerging meta‐optics unfold unprecedented capabilities in optical display, information storage, and encryption applications. Particularly, the recent advances in vectorial holography based on the multi‐parameter manipulation of the Jones matrix have increased the modulation space and information capacity. However, the fundamental degree of freedom (DoF) extreme limit in the optical encoding space of the Jones matrix bottlenecks the information capacity for high‐demand practical applications. To further expand the high‐volume encryption with enhanced security, here, a vectorial‐manipulating encryption strategy is proposed to originally demonstrate multi‐channel encryption and display. By ingeniously utilizing multi‐beam overlapping and precisely controlling their phase differences in the overlapping area, the capacity expansion of up to 12‐channel near‐/far‐field optical images is enabled. Such vectorial‐manipulating strategy is also applied to near‐field nanoprinting and realizes additional encrypted nanoprinting information. More intriguingly, the optical encryption will not be decrypted unless setting with a particular combination of input/output polarization keys, thus enhancing its concealment security beyond the conventional encryption. Overall, the proposed vectorial‐manipulating strategy expands the state‐of‐the‐art storage capacity with enhanced decipher security and potentially suggests a new path for the next‐generation optical storage and encryption security applications. [ABSTRACT FROM AUTHOR]

Hydrogel materials endow the flat optics platform with active tuning capability, owing to their remarkable humidity‐responsive swelling behavior. Despite recent advances in hydrogel‐based devices for spectral tuning, their complex patterning processing and limited functionality obstruct them from practical applications. Herein, a single‐step direct‐printing technique is originally demonstrated with an active hydrogel material platform for realizing unprecedented multi‐field full‐color display dynamics. Through exploring the dose‐induced shrinkage on polyvinyl alcohol, the stepwise hydrogel nanocavities sandwiched by ultrathin metallic films can be directly printed by grayscale e‐beam lithography. Due to the tunable structural coloration from hydrogel nanocavity scaling, multi‐functionalities are successfully created for optical concealment, dynamic coloring, and dynamic full‐color holography. By encoding the cavity‐dependent transmission phase into the direct‐printed hydrogel platform, it originally enables the projected full‐color holographic dynamics in real‐time by simply exhalation, beyond the static holographic display or monochromatic holographic switching. The proposed active displays can rapidly respond to the surrounding humidity change at a millisecond‐level (< 150 ms). Such a direct‐printing strategy for hydrogel nanocavity represents a critical advance toward the unprecedented dynamic full‐color display, and suggests promising applications in optical security, gas sensing, multispectral imaging, full‐color holography, and next‐generation display techniques. [ABSTRACT FROM AUTHOR]

Objectives: To determine the therapeutic effect of tetrahedral framework nucleic acids (tFNAs) on diabetic wound healing and the underlying mechanism. Materials and Methods: The tFNAs were characterized by polyacrylamide gel electrophoresis (PAGE), atomic force microscopy (AFM), transmission electron microscopy (TEM), dynamic light scattering (DLS) and zeta potential assays. Cell Counting Kit‐8 (CCK‐8) and migration assays were performed to evaluate the effects of tFNAs on cellular proliferation and migration. Quantitative polymerase chain reaction (Q‐PCR) and enzyme‐linked immunosorbent assay (ELISA) were used to detect the effect of tFNAs on growth factors. The function and role of tFNAs in diabetic wound healing were investigated using diabetic wound models, histological analyses and western blotting. Results: Cellular proliferation and migration were enhanced after treatment with tFNAs in a high‐glucose environment. The expression of growth factors was also facilitated by tFNAs in vitro. During in vivo experiments, tFNAs accelerated the healing process in diabetic wounds and promoted the regeneration of the epidermis, capillaries and collagen. Moreover, tFNAs increased the secretion of growth factors and activated the Wnt pathway in diabetic wounds. Conclusions: This study indicates that tFNAs can accelerate diabetic wound healing and have potential for the treatment of diabetic wounds. [ABSTRACT FROM AUTHOR]

With the great promise to reshape the landscape of photonic integrated circuits (PIC), the introduction of metasurface onto optical waveguide integration gives rise to tremendous potential functionalities via converting the guided waves to free‐space, including directional beam‐steering, mode‐conversion, optical on‐chip router, etc. Despite these endeavors, on‐chip metaoptics still faces critical challenges to achieve multifunctionalities with dynamic switchable ability between arbitrary‐encoding channels. Here, a series of novel on‐chip metaoptics functionalities are originally proposed and experimentally demonstrated. Through utilizing a serial optimization algorithm of computer‐generated hologram (CGH), a 3D hologram with multiple sliced information channels is successfully enabled to project above the on‐chip space. Moreover, by strategically exploring water immersive tuning scheme, on‐chip dynamic tuning in real‐time is realized for dual‐channel arbitrary‐encoded hologram, practically verified as a large‐scale easy‐accessible switch method. Eventually, the encoding freedom is further expanded by breaking the degeneracy of forward/backward guided propagations, beyond the state‐of‐art of multiplexing and information storage capacity. This study can easily find paths to numerous practical applications in the next generation of AR display, 3D vision, optical storage, and photonics integrated devices. [ABSTRACT FROM AUTHOR]

Heading toward the next‐generation versatile meta‐devices and meta‐systems with increasing complexity, it inevitably demands the cascading and coupling between multi‐layer metasurfaces to create new design space for meta‐optics. However, the accurate requirement for multilayer alignment at the nanoscale is significantly challenging due to the actual fabrication limitation, thus hindering the state‐of‐the‐art meta‐optics device integration and its practical application. Herein, a dynamic meta‐system for augmented reality (AR) holographic display functionality based on a layer‐folded metasurface integrated with an electrical‐driven liquid crystal (LC) platform is originally proposed and realized. By ingeniously folding the optical path between meta‐device vertical space, a beam‐steering metasurface in parallel with the other two holographic metasurfaces placed on a single surface is successfully cascaded. Such a layer‐folded scheme enjoys single‐time lithography processing for multi‐patterning with nanoscale alignment accuracy and avoids any vertical alignment issue. Furthermore, by combining with an electrical‐driven LC tuning scheme, the integrated meta‐system could actively switch independent‐encoded holographic images in real‐time floating in the actual‐world scene. Overall, it is envisioned that such a compact dynamic meta‐system suggests a feasible route for dynamic tunable wearable AR displays, intelligent dynamic displays, multi‐functional devices, etc. [ABSTRACT FROM AUTHOR]

The exploit of on‐chip metasurfaces with full optical controllability and multiplexing capability holds great promise for photonic integration circuits (PIC). Despite previous endeavors in metasurfaces controlling guided waves, it still faces critical challenges to realize practical display applications, for instance, augmented reality (AR). Here, a new type of AR based on multiplexed on‐chip meta‐holography is proposed and experimentally demonstrated by integrating judiciously engineered meta‐atoms above waveguide. Through hybridizing detour and Pancharatnam–Berry phases, on‐chip metasurfaces can independently manipulate both guided waves and free‐space light to enable a triple‐channel holography‐multiplexing with independent‐encoding freedom. Eventually, an RGB‐coloring AR hologram free from zero‐order diffraction that can project virtual images into a real‐world environment is realized, showcasing its significant potential for wearable devices (glasses or contact lens) integration. This study finds a feasible route toward multifunctional PIC devices and applications in wearable AR displays, imaging multiplexing, information storage, etc. [ABSTRACT FROM AUTHOR]

Although metasurface‐based devices exhibit great potential in optical display and storage technology, the challenges in practical nanoantenna fabrication limit their wide application. In parallel, flat optics, including planar thin‐film nanocavities, have also been extensively studied to realize various spectral engineering and imaging functionalities with large areas and simpler architecture. However, a longstanding practical challenge is to achieve multiplexing imaging functionalities with dynamic switchable ability in real‐time, which to date remains unexplored. In this study, by utilizing the typical inflation sensitivity of hydrogels to humidity change, a multiplexing imaging tunable strategy based on stepwise metal–hydrogel–metal (MHM) nanocavities is originally explored and demonstrated to exhibit dynamic switchable red–green–blue multichannel nanoprinting in real‐time. By decoupling the amplitude/phase correlation, MHM nanocavities successfully enable the hybrid encryption of simultaneous meta‐holography with independent‐encoding freedom in addition to multiplexing nanoprinting. Such an imaging approach, which employs a dynamic tuning scheme, paves a promising avenue toward various applications including state‐of‐the‐art tunable imaging display/storage/encryption, humidity optical sensors, and next‐generation dynamic augmented reality technology. [ABSTRACT FROM AUTHOR]

Metal–insulator–metal (MIM) nanocavity, as a lossy Fabry–Pérot (FP) scheme, has been widely studied for color filter and perfect absorber functionality, which can be integrated into functional photonic devices. However, such triple‐layered MIM still lacks the ability to induce multiple intensity levels for meticulous grayscale imaging because of strong spectral sensitivity to cavity thickness variation. Moreover, the MIM stack remains unexplored to multiplex a near‐field nanoprinting and holographic imaging because it is challenging to break the mutual dependence relation between the intensity and phase shift. Herein, a new film stack of dual‐Fabry–Pérot (DFP) nanocavity is proposed to create triple‐fold freedom in light modulations: intensity, phase shift and operation wavelength, which can be respectively modulated by the top/bottom/total cavity length. By spatially arranging the stepwise nanocavities, the designed DFP pattern can show multiplexing dual‐channel imaging, which encrypts/conceals a grayscale nanoprinting image and simultaneously projects a far‐field holographic image. Such DFP strategy allows for new possibility of independent light modulation and creates new dimensional degree of freedom for thin‐film nanocavity. The proposed functional DFP strategy enriches the subwavelength building block design for metasurfaces and thin‐film stacks, which would promisingly empower advanced applications in information multiplexing, imaging encryption/concealing, and many other related fields. [ABSTRACT FROM AUTHOR]

This paper clearly demonstrates the structure of Experimental Advanced Superconducting Tokamak (EAST) power supply system and analyzes principles of the finite-state machine (FSM) elaborately. Depending on the characteristics of EAST power supply system and the requirements of it, this paper chooses the real-time Linux as system platform and experimental physics and industrial control system (EPICS) as development tool to design a control system of the EAST poloidal field power system supply. This paper utilizes a temporal logic control based on the FSM in order to regulate the operation process of real-time sequence logic control of 12 sets of power controllers. This design is evaluated and tested, and it completely meets the real-time requirement of the poloidal field power supply (PFPS) control system. Several experiments have proved that this design definitely meets the real-time sequence logic control requirement of the PFPS control system in the complex situations under magnetic fields. [ABSTRACT FROM AUTHOR]

The International Thermonuclear Experimental Reactor (ITER) poloidal field (PF) ac/dc converter operates in four quadrants to provide the control of current necessary to PF coils for plasma initialization and the plasma shape control. The technical details for thyristor triggering of high-power ac/dc converter lay the foundation for the regular operation of ITER PF ac/dc converter. With the characteristics such as high power, complex operating modes of ac/dc converter, the synchronization, reliability, and high security have to be critically concerned in the pulse distributor design. In this paper, a pulse distributor is designed to convert the optical signal to high current electrical trigger pulse with less than 1- $\mu \text{s}$ rising time, thereby triggering the paralleled thyristors reliably and isolating 20-kV voltage from the converter unit to controller. Furthermore, the signals of crucial status are online acquired and encoded, then transmitted to controller by optical fiber, thus implementing the online status diagnosis to guarantee the safety operation of ITER PF ac/dc converter. The pulse distributor has been experimented in ITER PF ac/dc converter and all functions have been effectively verified. [ABSTRACT FROM AUTHOR]

Power system operations data are sometimes limited in a given space due to system collinearity. As such, the operations data recorded around an operating point of concern may be deficient or isotropically dispersed. Consequently, online sensitivity identification using ordinary regression methods is prone to large errors. In this paper, a locally weighted ridge regression method is proposed to overcome this problem. The norm-2 Tikhonov–Phillips regularization is integrated into the locally weighted linear regression. The integrated algorithm then has the ability to keep the online sensitivity identification stable if data are collinear while also accommodating the nonlinear and time-varying properties of the sensitivities. The mathematical derivation, online tuning, implementation, and practical considerations of the proposed method are presented. Its effectiveness is validated in a simulation system with operations data measured from real power systems. [ABSTRACT FROM AUTHOR]

The increasing amount of data recorded during power system operations and recently developed data-driven methods make online sensitivity identification (SI) a possibility. However, due to the inherent properties of power systems—nonlinearity, time variance, and collinearity—the effective data that carry the sensitivity information are insufficient. Consequently, the online SI information collected with existing methods may result in unexpected estimates. In this paper, a sufficient effective data condition that guarantees the success of online SI is proposed. The inherent properties of power systems and their impacts on this condition are then investigated. A series of metrics to qualify online whether the data meet the condition is put forward to assess the online SI results. A method is also proposed to select the effective data to improve the online computational efficiency. Finally, the findings and methods are validated in an eight-generator 36-node bus system with operations data recorded from actual power systems. [ABSTRACT FROM AUTHOR]

Measurement sensors installed in the smart transmission system can acquire big data for electromechanical dynamics monitoring. The time-series data obtained carry information of instantaneous relationship of system oscillation modes with respect to operating conditions. To extract this information, this paper proposes a parallel processed online supervised learning algorithm called k-nearest neighbors “locally weighted linear regression” (KNN-LWLR), which is an extensive combination of two famous machine-learning algorithms: 1) the KNN learning; and 2) LWLR learning. Its mathematical derivation, implementation, parameter tuning, and application to electromechanical oscillation mode prediction are first described. The proposed algorithm is then validated based on an 8-generator 36-node system with the real operations data. [ABSTRACT FROM PUBLISHER]

GLO:ET9/01nov22:cpr13357-toc-0001.jpg PHOTO (COLOR): . gl The cover image is based on the Original Article I Tetrahedral framework nucleic acids promote diabetic wound healing via the Wnt signalling pathway i by Zejing Wang et al., https://doi.org/10.1111/cpr.13316. [Extracted from the article]

Layer-folded metasurface, liquid crystals, meta-holography, multi-patterning alignment, switchable AR display, total internal reflection Through combining with the electrical-driven LC tuning scheme, it can achieve the AR display dynamics in a real-world scene for human eyes in real-time. Keywords: layer-folded metasurface; liquid crystals; meta-holography; multi-patterning alignment; switchable AR display; total internal reflection EN layer-folded metasurface liquid crystals meta-holography multi-patterning alignment switchable AR display total internal reflection 1 1 1 06/22/22 20220620 NES 220620 A dynamic meta-system for augmented reality (AR) holographic display based on a layer-folded metasurface integrated with electrical-driven liquid crystal (LC) platform is originally proposed and realized by Zhongyang Li and co-workers, as shown in article number 2200418. [Extracted from the article]

Through hybridizing detour and Pancharatnam-Berry phases, it can independently manipulate both guided waves and free-space light to enable a triple-channel holography-multiplexing, which showcases its significant potential for wearable devices (eyeglasses or contact lens) integration. Augmented Reality Enabled by On-Chip Meta-Holography Multiplexing Light (Laser Photonics Rev. 16(6)/2022) B Augmented Reality Holograms b A miniaturized augmented reality hologram free from zero-order diffraction based on multiplexed on-chip meta-holography is demonstrated by Zhongyang Li and colleagues in article number 2100638. [Extracted from the article]

Myocardial perfusion studies using dynamic contrast-enhanced cardiac magnetic resonance imaging (CMRI) could provide valuable, quantitative information regarding heart physiology in diseases such as Duchenne muscular dystrophy (DMD), that lead to diffuse myocardial damage. The goal of this effort was to develop an intuitive but physiologically meaningful method for quantifying myocardial perfusion by CMRI and to test its ability to detect global myocardial differences in a dog model of DMD. A discrete-time model was developed that parameterizes contrast agent kinetics in terms of an uptake coefficient that describes the forward flux of contrast agent into the tissue, and a retention coefficient that describes the rate of decay in tissue concentration due to contrast agent efflux. This model was tested in 5 dogs with DMD and 6 healthy controls which were imaged using a perfusion sequence on a 3T clinical scanner. CINE and delayed-enhancement CMRI acquisitions were also used to assess cardiac function and the presence of myocardial scar. Among functional parameters measured by CMRI, no significant differences were observed. No myocardial scar was observed. Increased perfusion in DMD was observed with an uptake coefficient of 6.76 ± 2.41 % compared to 2.98 ± 1.46 % in controls ( p = 0.03). Additionally, the retention coefficient appeared lower at 82.2 ± 5.8 % in dogs with DMD compared to 90.5 ± 6.6 % in controls ( p = 0.12). A discrete-time kinetic model of uptake and retention of contrast agent in perfusion CMRI shows potential for the study of DMD. [ABSTRACT FROM AUTHOR]

Streptozotocin (STZ)-induced diabetes causes an upregulation in the expression of endothelin (ET) receptors in the rat prostate (Eur J Pharmacol 310:197, 1996). We examined the effects of insulin treatment, started 8 weeks after the induction of diabetes, on the expression and distribution of ET receptors and their respective mRNAs in the rat prostate. The densities, pharmacological properties and distribution of ET receptors in the rat prostate were examined using radioligand receptor binding and autoradiographic studies, and gene expression of ET receptors was evaluated utilizing the reverse transcription-polymerase chain reaction (RT-PCR). STZ-injected rats had smaller prostates and reduced serum testosterone levels than control and insulin treated diabetic animals. ET receptor density was shown to be significantly higher in the prostate from diabetic rats than those from either control or insulin treated diabetic animals. The pharmacological profile of prostatic ET receptors was similar in all groups (approximately 80% ETA; 20% ETB subtype). ET receptors were predominantly localized to the prostatic stroma. Induction of diabetes increased the expression of mRNA levels of ETA and ETB receptors, and insulin treatment reversed this upregulation to control levels. These results indicate that (1) ET receptor subtypes are expressed in the rat prostate as transcription and translation products; (2) insulin can normalize the diabetes-induced upregulation in the expression of ET receptors and their respective mRNAs; and (3) diabetes-induced regression of the prostate may involve an alteration in ET receptors. [ABSTRACT FROM AUTHOR]