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Diabetic foot is one of the most severe complications of diabetes. It is caused by high blood sugar, resulting in combined neuropathy and various degrees of peripheral vascular disease, leading to local microcirculation disorders. This condition can trigger infections, ulcers, and deep tissue damage in the lower limbs. In severe cases, gangrene may occur, leading to amputation. Therefore, timely microcirculation monitoring of the feet in diabetic patients can help detect early blood supply issues. Prompt and effective intervention and treatment for diabetic patients with microcirculation disorders in the feet can prevent the occurrence and development of diabetic foot. Physical factor therapy utilizes various forms of physical energy to induce reactions in the body, such as dilating blood vessels, increasing blood flow, and promoting tissue blood supply. Simultaneously, it stimulates nerves and muscles, aiding in improving nerve conduction and promoting nerve regeneration. This helps prevent and improve microcirculation disorders in diabetic feet. This article outlines the microcirculation disorders in diabetic feet, along with monitoring and treatment methods. It focuses on the principles and efficacy of common physical factor methods for microcirculation intervention, as well as research advancements in their clinical application for diabetic foot. This information serves as a reference for the treatment and adjunctive research of diabetic foot.

In this paper, we propose a deep learning approach for forward modeling and inverse design of photonic devices containing embedded active metasurface structures. In particular, we demonstrate that combining neural network design of metasurfaces with scattering matrix-based optimization significantly simplifies the computational overhead while facilitating accurate objective-driven design. As an example, we apply our approach to the design of a continuously tunable bandpass filter in the mid-wave infrared, featuring narrow passband (∼10 nm), high quality factors (Q-factors ∼ 102), and large out-of-band rejection (optical density ≥ 3). The design consists of an optical phase-change material Ge2Sb2Se4Te (GSST) metasurface atop a silicon heater sandwiched between two distributed Bragg reflectors (DBRs). The proposed design approach can be generalized to the modeling and inverse design of arbitrary response photonic devices incorporating active metasurfaces.

Background: To evaluate the effects of nitroglycerin combined with continuous regional arterial infusion (CRAI) on severe acute pancreatitis (SAP), triglyceride (TG), inflammatory factors and prognosis.

Background Multicompartmental osteoarthritis (MOA) in both tibiofemoral and patellofemoral joints is a more commonly occurring, but neglected, clinical condition, and we examined the short-term safety and efficacy of autologous stromal vascular fractions (SVFs) for MOA using a single-blind, prospective, randomized, placebo-controlled trial. Methods Seventy MOA patients were recruited and randomly assigned to the SVF group and hyaluronic acid (HA) group (control group). The scores of visual analog scale, the Western Ontario and McMaster University Osteoarthritis Index, and the Samsung Medical Center patellofemoral scoring system were assessed and compared between the two groups 3, 6 and 12 months after treatment. Results The SVF group had significantly better visual analog scale scores than the HA group at 6 and 12 months after treatment and had better Western Ontario and McMaster University Osteoarthritis Index scores than the HA group only at 6 months after treatment. For Samsung Medical Center patellofemoral scoring system of the patellofemoral joint, the SVF group had significantly better scores than the control group at all postoperative time points. The proportion of patients whose visual analog scale and Western Ontario and McMaster University Osteoarthritis Index scores were above the minimal clinically important improvement was higher in the SVF group than in the HA group in the majority of assessments. The improvement of bone marrow by SVF treatment was significantly better than that of the HA group as observed by pre- and postoperative Magnetic resonance imaging (MRI). Conclusions Multiple intra-articular injection of autologous SVF reduces pain and improves function in the short term in patients with early or midstage MOA. However, there was heterogeneity in the improvement of overall knee and isolated patellofemoral joint after treatment.   What is already known on this topic   Knee osteoarthritis (KOA) is the most common type of degenerative joint disease in humans. Autologous stromal vascular fraction (SVF) has been gradually applied to the treatment of KOA due to its multidifferentiation and ease of access. However, most current studies have focused on the tibiofemoral (TF) joint, and we know little about the performance of SVF in multiple compartments of the knee, including the patellofemoral (PF) joint. What this study adds   Multiple intra-articular injections of SVF are safe and effective for MOA in short-term (within 12 months) follow-up. Patients with MOA appear to have different feedback on treatment in different compartments of the knee, including the PF and TF joints, after SVF treatment. How this study might affect research, practice, or policy   More research is needed to clarify the appropriate dosage and injection schedule of SVF to standardize its clinical use. The rational selection of the indications for SVF in the treatment of KOA needs to be done more carefully when OA affects multiple compartments of the knee joint. [ABSTRACT FROM AUTHOR]

This work presents an approach for the automatic modeling and high-efficiency simulation of the mechanical properties of plain-woven composites. For the beam element finite element model, a technical scheme for the automatic modeling of plain-woven fabrics is presented. Considering the constraint relationship between the matrix and the fibers, a method for creating matrix beam elements is proposed. Then, a beam element solver was compiled to simulate the tensile properties of the plain-woven composites. In addition, a method of rendering a three-dimensional model of yarn and the simulation results were presented, and a comparison between real fabric images and modeled fabric structure confirmed that the method proposed in this work could effectively model plain-weave fabric structures. Experimental results showed that the deviations of the tensile modulus and strength were 0.41% and −7.59% respectively, which verified the validity of the beam element model used in this study. Moreover, testing verification of the method used in this study could realize the automatic modeling and simulation of representative cells of plain-woven composites in a few seconds. The above results show that this work offers the potential to handle the efficient calculations of large-scale woven structure models. [ABSTRACT FROM AUTHOR]

This work presents a beam element approach for the modeling and high-efficiency simulation of mechanical properties of 2.5D woven composite. For the beam element model, a technical scheme for the parametric modeling of 2.5D woven fabrics was produced. Considering the constraint relationship between the matrix and the fibers, we proposed a method for creating matrix beam elements. Then, a beam element solver was compiled to simulate the mechanical properties of the 2.5D woven composite. Meso-scale analysis of curved shallow-crossing linking 2.5D woven composite using the proposed model obtained the accurate tensile modulus. Full-scale analysis was implemented to simulate bending behavior of straight shallow-crossing linking 2.5D woven composite, and the simulation results agreed well with the experimental results. The above analysis could automatically complete modeling, analysis and post-processing in a relatively short time, reflecting the efficiency advantages of the method in this paper. [ABSTRACT FROM AUTHOR]

Optical metasurfaces, planar subwavelength nanoantenna arrays with the singular ability to sculpt wavefront in almost arbitrary manners, are poised to become a powerful tool enabling compact and high-performance optics with novel functionalities. A particularly intriguing research direction within this field is active metasurfaces, whose optical response can be dynamically tuned postfabrication, thus allowing a plurality of applications unattainable with traditional bulk optics. Designing reconfigurable optics based on active metasurfaces is, however, presented with a unique challenge, since the optical quality of the devices must be optimized at multiple optical states. In this article, we provide a critical review on the active meta-optics design principles and algorithms that are applied across structural hierarchies ranging from single meta-atoms to full meta-optical devices. The discussed approaches are illustrated by specific examples of reconfigurable metasurfaces based on optical phase-change materials.

Patterns composed of micron‐sized surface structures can abruptly change the properties of an optical wave front, including its phase, amplitude, polarization, and dispersion. Optical components featuring surface micro‐gratings not only possess optical functionalities that can rival or exceed those of traditional bulky components but can also significantly improve the compactness of optical systems. Herein, the design and fabrication process of As2S3 glass‐based micro‐gratings as well as their resulting optical functionality in the infrared regime are reported. The novel two‐step photochemical process consists of spatially controlled direct laser writing and subsequent selective solution etching. The process yields surface micro‐gratings that possess arbitrarily tunable geometries and design patterns on large‐area flat and curved optical surfaces or substrates, offering a potential new avenue for developing aberration‐corrected infrared‐imaging systems. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells (SOFCs) represent a class of energy conversion devices that exhibit exceptional efficiency in the direct conversion of chemical energy from diverse fuel sources into electricity. The cathode, which is responsible for the oxygen reduction reaction (ORR) and electron transfer in the cell, plays a critical role in determining the overall performance of SOFCs. In recent years, triple conducting perovskite (TCP) materials have attracted increasing attention as cathode materials for SOFCs due to their excellent electrocatalytic activity, high electronic and ionic conductivity, and thermal stability at high temperatures. This review paper provides a comprehensive overview of the TCP cathode materials used in SOFCs. In this paper, we first introduce the basic principles and working mechanism of SOFCs. Then, we discuss the current research status of the TCP cathodes, including their compositions, structures, and performance characteristics. Moreover, we highlight the recent advances in the development of new cathode materials and strategies to enhance the overall performance of SOFCs. Finally, we provide insights into the future research directions and potential applications of TCP cathodes in SOFCs. This review aims to offer a comprehensive understanding of the TCP cathodes and facilitate the development of more efficient and cost-effective SOFCs. [ABSTRACT FROM AUTHOR]

In this work, an ultra‐wideband double slot Vivaldi antenna (DSVA) loaded with a novel wideband nonresonant metasurface is proposed to enhance the gain. The semi‐elliptical slots are etched on both sides of the ground plane of the DSVA to improve the current distribution. In addition, the nonresonant metasurface composed of WiFi‐shaped unit cells could maintain a stable high refractive index in the operating bandwidth of 1−18 GHz, which could bend the outgoing wave to the end‐fire direction. Both the original antenna and the proposed antenna are simulated, fabricated, and characterized. The measured results are in good accordance with the simulated ones. The return losses of both antennas are less than −10 dB in the frequency range of 2−13.4 GHz, while the gain of the proposed antenna is improved from 13.6 to 16.3 dBi with a maximum gain enhancement of 3.1 dB. [ABSTRACT FROM AUTHOR]

Aiming at the problems of low search efficiency, unsmooth path, and easy collision with obstacle vertices when using D* Lite algorithm for mobile robot path planning in dynamic environment, a new method based on risk factor and cubic uniform R-spline curve was proposed. First, perform function optimization. When expanding the adjacent points, the traditional heuristic function calculation method is changed to the diagonal distance to improve the planning efficiency, and the risk factors are fine grated into the node cost, so as to avoid the robot moving obliquely through the sharp corners of obstacles and colliding with the sharp corners of obstacles; Secondly, the path is fitted and optimized by combining the cubic uniform B-spline curve to make the path smoother. Aiming at the above improvements, PyCharm software is used to simulate, and the results show that the improved algorithm can effectively improve the efficiency of path planning and the safety and practicability of paths. [ABSTRACT FROM AUTHOR]

The loss prediction model plays a crucial role in turbine design for fast performance prediction and a shorter design cycle. Owing to the design requirements of high-efficiency turbines under a wide range of operating conditions, the loss prediction of the off-design incidence is increasingly important. However, limited by the modeling database and traditional modeling methods, the accuracy and adaptability of the existing off-design incidence loss predictions are insufficient. This paper proposes an adaptive prediction method based on machine learning and develops a multi-objective optimization process based on adaptive prediction. Machine learning (neural network) is applied for more flexible and accurate loss predictions over a wide incidence range. Compared with two classic loss models (Ainley and Mathieson model and Benner model), the adaptive prediction model significantly improves the ability to predict turbine profile loss with off-design incidence, particularly under large incidence conditions. The prediction root mean square error can be reduced by up to 73.8% (absolute value: 0.063). Furthermore, the multi-objective optimization method based on adaptive prediction is applied to the aerodynamic optimization of the original cascades with a wide incidence range. The weighted objective of the optimized cascade (Cri = 0.211) is reduced by 8.7% compared with that of the original cascade (Cri = 0.231). Within the range of full incidence angle (−40° to +20°), the variation of profile loss is reduced by 24.0%. This study is a preliminary exploration aimed at establishing an accurate turbine loss prediction system based on machine learning, the feasibility, and superiority of this approach are confirmed. [ABSTRACT FROM AUTHOR]

With the strong advancement of the global carbon reduction strategy and the rapid development of renewable energy, compressed air energy storage (CAES) technology has received more and more attention for its key role in large-scale renewable energy access. This paper summarizes the coupling systems of CAES and wind, solar, and biomass energies from the perspective of system topology, and points out the advantages and limitations of each system. It is shown that the coupling of wind energy and CAES is mainly combined in series and in parallel, and sometimes part of the wind power can be converted into thermal energy when coupled to CAES. The coupling between solar heat and CAES is an important form of coupling between solar energy and CAES. Solar-heat-coupled CAES mainly uses solar energy to heat expander inlet air. The coupling forms of solar energy and CAES are based on various CAES forms, various heat heating sequences, reheating, bottom cycle, and other factors. The combination of biomass and CAES is generally based on biomass gasification power generation technology. In the future, a wind–solar–CAES multiple coupling system is expected to become a promising large-scale form for the utilization of renewable energy, and this integrated system has great potential as a system configuration, but has some technical challenges. [ABSTRACT FROM AUTHOR]

Holography based on optical metasurfaces has attracted a steadily increasing interest. However, most of the optical metasurfaces usually suffer from limited number and fixed viewing angles of multiplexed holography images in one channel. Here, by modifying the Gerchberg–Saxton algorithm, a multiplexed holography at arbitrary‐planes is proposed at two arbitrary microwave frequency bands. As a proof‐of‐concept demonstration, two independent information channels can be established by a single metasurface through dual‐frequency meta‐atoms. The metasurface composed of 35 × 35 meta‐atoms can simultaneously produce four images with 45° and 60° viewing angles at 10 GHz and five images with vertical and horizontal viewing angles at 16 GHz. The experimental results verify the design concept, making it possible to generate multiplexed holography in arbitrary‐planes, and allowing multiplexed functionalities in a variety of applications such as microscopy, display, security, data storage, and information processing. [ABSTRACT FROM AUTHOR]

Dynamic uncertainties and unknown disturbances will degrade the tracking performance of robots. When using a disturber observer-based controller, the key to effectively compensate for these uncertainties is to measure or estimate as accurately as possible any disturbance. To relax restrictions on the design of the current nonlinear disturbance observer for the robot, a universal nonlinear disturbance observer is proposed for higher estimation performance. The stability of the proposed universal nonlinear disturbance observer is theoretically analyzed and the boundaries of estimation error are proven according to the vector differential equation. Finally, the proposed universal nonlinear disturbance observer is evaluated via simulation by comparison to the nonlinear disturbance observer. The result shows a faster estimation speed and a higher estimation accuracy of the universal nonlinear disturbance observer. [ABSTRACT FROM AUTHOR]

A novel design of circularly polarized broadband slot antenna with high gain, low profile, and low radar cross‐section (RCS) is proposed by employing polarization conversion metasurface (MS). By introducing sawtooth corner‐truncated square MS with diagonal gaps, a compact circularly polarized antenna composed of 4 × 4 unit cells is presented. It is found that a smaller MS slot antenna can achieve an impedance bandwidth of 42.9% (3.7–5.72 GHz) and a 3‐dB axial ratio (AR) bandwidth of 22.8% (4.55–5.72 GHz). Simultaneously, the MS can realize polarization conversion. The MS and its orthogonal units were arranged in a chessboard‐type pattern and applied as the radiator of a larger MS slot antenna, which was fed by a sequentially rotated feeding network. In addition, owing to the anti‐phase cancellation and scattering, the 5‐dB average RCS reduction can be obtained within the frequency range from 3.8 to 6.9 GHz. For verification, the proposed larger circularly polarized antenna was fabricated and tested. The operating bandwidth was measured as 44% (3.78–5.91 GHz) with a 3‐dB AR bandwidth of 39.6% and a high gain of 10.3 dBic. Furthermore, the larger antenna produces a useful RCS reduction from 3.7 to 6.7 GHz. The simulated and measured results are in good agreement. [ABSTRACT FROM AUTHOR]

High-resolution endoscopic optical imaging is a crucial technique in biological imaging to examine the inside organs. There is a trade-off between lateral resolution and depth of focus in such applications. Traditional Optical Coherence Tomography provides an increased depth range but falls short of desired resolution. The combination of both higher resolution and larger imaging depth of focus of metalens can improve the clinical utility of endoscopic optical imaging. In this work, we designed, analyzed, and fabricated a 500 µm diameter metalens operating at 1300 nm to achieve high resolution and large imaging depth of focus, therefore, addressing this need. The full width at half maximum and depth of focus for the proposed metalens are 3.10 and 286 µm, respectively. [ABSTRACT FROM AUTHOR]