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We propose a radio frequency (RF) and visibly transparent composite metasurface design comprising newly developed transparent multilayer conductive coatings. Detailed experimental and theoretical analysis of the RF/visible transparency of the proposed meta-glass is provided. The proposed nature-inspired symmetrical honeycomb-shaped meta-glass design, alters the electromagnetic properties of the glass substrate in the RF spectrum by utilizing visibly transparent Ag-based conductive coatings on each side. Furthermore, the competing effect of the Ag thickness on optical and RF transparency is discussed. We show that using multilayer dielectric-metal coatings, specifically 5-layered spectrally selective coatings, RF transparency of the meta-glass can be enhanced while preserving visible transparency. Herein we demonstrate high transparency meta-glass with 83% and 78% peak RF and optical transmission at 28 GHz and 550 nm, respectively. The meta-glass yields enhanced RF transmission by 80% and 10% when compared to low-emissivity glass and bare glass, respectively. The meta-glass design presented here is amenable to a variety of 5G applications including automobile radar systems. This work provides a superior alternative to the standard indium-tin-oxide (ITO) transparent material which is becoming scarce. Moreover, this study paves the way for the design of new visibly transparent metamaterials and artificial dielectrics.

This paper presents a novel detection and rerouting mechanism for distributed adaptive platoon control of non‐linear autonomous connected vehicles under denial of service (DoS) attacks. DoS attacks can cause delays or losses of data packets due to blocked communication channels, leading to reducing platoon performance or even collisions among vehicles. To tackle this issue, the proposed mechanism detects and reroutes communication topology depending on the real‐time topology and the number of link failures. Real‐time detection divides the scenario of DoS attacks into three parts. According to the different scenarios, rerouting mechanisms will be utilized. A controller adapted to real‐time variable communication topology is also designed in this scheme. The adjacency matrix of the real‐time communication topology generated by the rerouting mechanism is used to update the controller so that the platoon can remain in a stable state without being affected by DoS attacks. In addition, the sliding mode controller and the observer are designed by solving linear matrix inequalities, and the platoon stability and internal stability are proven. Numerical simulation studies demonstrate that the proposed mechanism and control design can reduce the vehicle state estimate error and platoon‐tracking error to ideal states under DoS attacks. The proposed method solves the problem that the existing methods have not considered the number of link failures and the inability to restore communication when the communication topology is paralyzed. [ABSTRACT FROM AUTHOR]

Controller area network (CAN) is the most commonly used bus technology for In-vehicle network and uses multicast communication without corresponding security measures. Therefore, the message data field is vulnerable to tampering and other attacks. Recent machine learning-based intrusion detection methods for CAN bus messages only use the information contained in the message data field and do not take into account the contribution made by the neighboring information of CAN bus messages. In addition, previous models considered the data domain information of CAN bus messages as separate features and did not consider the unique weight of each feature, as well as the second-order interaction information between features. Therefore, we propose a novel intrusion detection model, The Hybrid Similar Neighborhood Robust Factorization Machine Model (HSNRFM), for detecting anomalies in CAN bus messages to address the shortcomings and problems of the previous models. To be able to incorporate the contribution of similar neighborhood information and learn the unique weight parameters of each feature in the model decision process, as well as additional second-order interaction information between features, the HSNRFM model solves the above problem using a similarity calculation method and a factorization machine model. Comprehensive experimental results are compared on real vehicle datasets. The HSNRFM model has AUC values of 0.9216 and 0.901 and AUPR values of 0.9194 and 0.9018 on two real datasets, respectively. And the results show that our proposed HSNRFM model has excellent detection efficiency for intrusion detection of CAN bus messages. [ABSTRACT FROM AUTHOR]

An IR optical transmitarray is presented based on Antenna Array Sheet (AAS) for the manipulation of circularly polarized light. The unit cell of the transmitarray comprises three layers of metallic elliptical patches. Complete phase control is achieved through the local rotation of each unit cell. Thin refraction and focusing transmitarrays of this sort are demonstrated at infrared frequencies. Moreover, a new concept for realizing a polarization-discriminating device is introduced based on a flat refracting lens. These devices are compatible with current fabrication technology and can become crucial for the integration with other IR and nano-photonic devices.

In this article, we analysed the problems of electronic medical records (EMRs) and found that the EMRs generated by different hospitals for the same patient are mutually independent and duplication and data sharing are difficult among hospitals. In order to solve this problem, this paper proposes an efficient and secure cross-domain sharing scheme of EMRs based on edge computing. The program allows the doctor to access the personal history EMRs through the patient's authorization so that the doctor can understand the patient's history of illness and, on this basis, generate a new medical record for the patient. Then, the doctor sends the EMRs to the edge server, and the server calculates the ciphertext and adds it to the patient's personal medical record to complete the case update. Analysis shows that this solution can effectively prevent data tampering and forgery through blockchain and avoid privacy leakage problems in plaintext sharing by using searchable encryption and by relying on edge servers to solve nearby computing tasks and divert the computing capacity of cloud servers to improve efficiency. The security proof shows that the scheme satisfies the complex problem of the BDH assumption. Performance analysis shows that the scheme is feasible and efficient. [ABSTRACT FROM AUTHOR]

Nanozymes, as a kind of artificial mimic enzymes, have superior catalytic capacity and stability. As lack of O2 in tumor cells can cause resistance to drugs, we designed drug delivery liposomes (MnO2-PTX/Ce6@lips) loaded with catalase-like nanozymes of manganese dioxide nanoparticles (MnO2 NPs), paclitaxel (PTX) and chlorin e6 (Ce6) to consume tumor's native H2O2 and produce O2. Based on the catalysis of MnO2 NPs, a large amount of oxygen was produced by MnO2-PTX/Ce6@lips to burst the liposomes and achieve a responsive release of the loaded drug (paclitaxel), and the released O2 relieved the chemoresistance of tumor cells and provided raw materials for photodynamic therapy. Subsequently, MnO2 NPs were decomposed into Mn2+ in an acidic tumor environment to be used as contrast agents for magnetic resonance imaging. The MnO2-PTX/Ce6@lips enhanced the efficacy of chemotherapy and photodynamic therapy (PDT) in bearing-tumor mice, even achieving complete cure. These results indicated the great potential of MnO2-PTX/Ce6@lips for the modulation of the TME and the enhancement of chemotherapy and PDT along with MRI tracing in the treatment of tumors. [ABSTRACT FROM AUTHOR]

Herein, cobalt-involved redox in a magnetically responsive drug-loaded nanocatalyst (PTX/Co-Lips@Fe3O4) was used to convert Fe(III) to Fe(II) for enhancing tumor ferrotherapy for the first time. Moreover, this work highlighted an "all in one" strategy: (1) targeting, chemotherapy, and ferrotherapy in one nanomedicine, and (2) a decrease in GSH quantity, increase in the quantity of efficient catalytic ions, and use of a magnetic field, all in one tumor ferrotherapy enhancement approach. [ABSTRACT FROM AUTHOR]

Aim: To synthesize a drug-delivery system with chemo-photothermal function and magnetic targeting, to validate its antitumor effect. Materials & methods: Parthenolide (PTL), employing chemotherapy and indocyanine green (ICG) providing phototherapy, were encased separately in the lipid and aqueous phases of liposomes (Lips). The Fe3O4 nanoparticles (MNPs), endowing magnetic targeting, were modified on the surface of Lips. The antitumor effects were investigated in vitro and in vivo. Results: ICG-PTL-Lips@MNPs showed outstanding synergistic antitumor efficacy in vitro and in vivo. Especially, after 14-day treatment, the tumor volumes decreased significantly and the biotoxicity was very low. Conclusion: The designed ICG-PTL-Lips@MNPs possess synergistic effects of chemotherapy, photothermal and targeting therapy, which are expected to provide an alternative way to further improve antitumor efficacy. Schematic illustration of the ICG-PTL-Lips@MNPs formation and the antitumor effect under magnet plus 808-nm near-infrared laser irradiation. [ABSTRACT FROM AUTHOR]

Antireflection has been a critical part in the design of optical and opto-electronic instruments. In the emerging millimeter (mm)-wave technology for the next-generation communication and autonomous driving, antireflection treatment is increasingly important due to the quasi-optical nature of electromagnetic waves at high frequencies. Enclosures that protect radar or communication phased arrays will introduce reflections if they are not designed properly. In this article, a novel metamaterial radome (meta-radome) is developed based on closely spaced metallic square meshes patterned on a thin dielectric substrate. We show that by deliberately employing the coupling between the meshes, the entire structure can be treated as a homogenized metamaterial slab with its wave impedance matched to that of free space. The resulting meta-radome can be optimized to have good transmission (> 90%) over an extremely wide range of angles of incidence (0° – 80°) for both transverse-electric (TE) and transverse-magnetic (TM) polarizations. Since the meta-radome is not resonant, it has a very small Ohmic loss and broad bandwidth. In addition, the proposed meta-radome is very easy to fabricate with standard fabrication techniques. Thus, it can be very attractive for many practical microwave and mm-wave applications. [ABSTRACT FROM AUTHOR]

In this paper, a miniaturized circularly polarized (CP) continuous wave Doppler radar system operating at 2.4 GHz is presented. The radar front end consists of one left-handed CP (LHCP) antenna and one right-handed CP (RHCP) antenna, which share a single patch antenna aperture. Orthogonal polarization is achieved through a modified ring-shaped quadrature hybrid coupler (QHC), and the resulting isolation between the two CP antennas is better than 30 dB. With 0 dBm input power to the transmitting antenna, the proposed radar system can accurately detect heartbeat and respiration movements of human test subjects under 1 m and over a wide angular range. The single dual CP antenna achieves 280% size reduction compared to a traditional two linear polarization patch antenna array with the same isolation level. [ABSTRACT FROM AUTHOR]

With the rapid development of photothermal therapy (PTT) in cancer treatment, it is necessary to obtain effective plasma-responsive tunable photothermal transducing agents. Inspired by the peptide-directed hierarchical mineralized Ag nanocages (Ag NCs), scientists designed a new duel-template cascade preparation method, and novel unique multi-branched gold nanoshells (BGSs) were successfully prepared under mild conditions using green strategy. The length, density and diameter of the branches were tuned, which led to the adjustment of the surface plasma response of the nanostructure. Because of the hierarchical structure and anisotropic surface, an obvious red shift of the local surface plasmon resonance spectrum was observed for the branched Au nanoshells. The excellent photothermal conversion efficiency (70.9%) and photo-induced heating responsive curves proved the superior photothermal conversion performance and photothermal stability of BGSs. The in vitro and in vivo results indicated that the heat generated by the intense NIR absorption of BGSs can selectively destroy cancer cells under laser irradiation. The nanostructures with ultrastrong absorption have promising prospects in tumor therapy. [ABSTRACT FROM AUTHOR]

Aim: We developed octreotide-modified magnetic liposomes (OMlips) as dual-targeting drug carriers to enhance the drug accumulation in tumor site. Materials & methods: Octreotide acts as a modified ligand for receptor-mediated targeting and the coated Fe3O4 nanoparticles offer the magnetic targeting property. SSTR2 overexpressed A549 cells and S180 cells were chosen to explore the targeting ability and antitumor effect of the oleanolic acid (OA)-loaded OMlips in vitro and in vivo. Results: The OMlips platform significantly improves the targeting, penetrating and accumulation of OA at the SSTR2 overexpressed cells and SSTR2-positive tumor-bearing mice. Conclusion: The OA-loaded OMlips have better antitumor effect and lower systemic toxicity. Such a receptor-mediated and magnetically-orienting dual-targeting drug nanocarriers may have great potentials in clinical practice. [ABSTRACT FROM AUTHOR]

Aim: To design and synthesize a novel multistimuli-responsive drug vehicle based on gold nanoflowers (AuNFs) for chemophotothermal synergistic cancer therapy. Materials & methods: Multistimuli-responsive drug-delivery system based on doxorubicin (DOX)/polydopamine (PDA)-functionalized AuNFs (Lan-AuNFs@PDA/DOX) was prepared. The structural characteristics, photothermal properties and stimuli-responsive drug release properties of Lan-AuNFs@PDA/DOX were evaluated. Antitumor studies in vivo and in vitro were performed. Results: Lan-AuNFs@PDA/DOX exhibited uniform morphology, excellent biocompatibility and photothermal conversion efficiency, which could also respond to stimulus including near infrared light and pH to trigger on demand drug release. The excellent synergistic therapeutic efficacy was confirmed both in vitro and in vivo. Conclusion: Lan-AuNFs@PDA/DOX would be a promising drug carrier, endowing a great potential for multistimuli-responsive chemophotothermal synergistic cancer therapy. [ABSTRACT FROM AUTHOR]

In traffic systems, cooperative driving has attracted the researchers’ attention. A lot of works attempt to understand the effects of cooperative driving behavior and/or time delays on traffic flow dynamics for specific traffic flow models. This paper is a new attempt to investigate analyses of linear stability and weak nonlinearity for the general car-following model with consideration of cooperation and time delays. We derive linear stability condition and study how the combinations of cooperation and time delays affect the stability of traffic flow. Burgers’ equation and Korteweg de Vries’ (KdV) equation for car-following model considering cooperation and time delays are derived. Their solitary wave solutions and constraint conditions are concluded. We investigate the property of cooperative optimal velocity (OV) model which estimates the combinations of cooperation and time delays about the evolution of traffic waves using both analytic and numerical methods. The results indicate that delays and cooperation are model-dependent, and cooperative behavior could inhibit the stabilization of traffic flow. Moreover, delays of sensing relative motion are easy to trigger the traffic waves; delays of sensing host vehicle are beneficial to relieve the instability effect to a certain extent. [ABSTRACT FROM AUTHOR]

Low reflection, low-loss, and wideband graded-index (GRIN) flat artificial dielectric lenses utilizing GRIN antireflection (AR) layers are developed in this paper. The GRIN lens and the AR layers are realized by perforating regular microwave substrates. The resulting reflectance, transmittance, and dielectric losses of the designed lens are 0.06% (−32.2 dB), 96.7% (−0.14 dB), and 3.3% (−14.8 dB), respectively. This highly efficient lens is designed to collimate a commercial pyramidal horn at 34.3 GHz. Excellent agreement is observed between the simulated and measured results. The flat lens decreases the half-power beamwidth of the horn from 10° to 6° and increases the peak gain by an average of 5 dB within the frequency range of 26–39 GHz. [ABSTRACT FROM PUBLISHER]

A novel antireflection (AR) theory based on an anisotropic metamaterial is presented in this paper. Based on this theory, we derive the required anisotropic material parameters for perfecting matching at a particular frequency for a particular angle of incidence, including extreme angles. For a proof of concept, the anisotropic AR layers are synthesized with metamaterial structures and near perfect matching is demonstrated in simulation at 88° incidence for both transverse-electric and transverse-magnetic polarizations. For experimental validation, the AR layer is redesigned to match at 60° in order to avoid spill-over losses in the quasi-optical measurement due to the finite substrate size. Excellent agreement is observed between the simulation and measurement results. [ABSTRACT FROM PUBLISHER]

In recent years, there has been increasing interest in fabricating noble metal nanoparticles using bio-templates for various biomedical applications, with the hope of finding a low cost method for their construction by a fairly simple and environmentally friendly synthetic strategy. In this study, novel self-assembled superstructures, namely, bacitracin–platinum nanoparticles (Bac–PtNPs), were designed and prepared under mild conditions. Bacitracin has two purposes: self-assembly to form a specific structure and the recognition of platinum nanoparticles, providing nucleation sites to form the nanomaterials. The spherical chain-like Bac–PtNPs were synthesized by the incubation of bacitracin and PtCl4 aqueous solutions at pH 2.0 for 24 h. The nanoparticles were face-centered cubic (fcc) crystalline, which were stable in aqueous solution. Functional groups such as –NH and –OH on the bacitracin surface serve as binding moieties and mediated the initial growth of the Pt nanoparticles. Anti-tumor effects exhibiting excellent therapeutic efficacy were confirmed both in vitro and in vivo. This study introduces a simple and effective platform for the design and preparation of the antitumor nanocomplexes, highlighting their potential applications in the biomedical field. [ABSTRACT FROM AUTHOR]

Aim: To prepare and validate the efficacy of a novel targeted drug delivery system - octreotide (Oct)-modified oleanolic acid (OA) liposomes. Materials & methods: OA liposomes (OA-L) were prepared by an ethanol injection method. The Oct-modified OA liposomes (O-OA-L) were synthesized and their properties were evaluated. Cellular uptake and competition inhibition studies were performed. Results: The OA vesicles presented satisfactory particles size (100-200 nm), stability and drug release characteristics; their ζ potential was -1.42 ± 0.08 mV. The O-OA-L had a higher cell proliferation inhibitory activity and cellular uptake than that of OA-L for somatostatin receptor-positive A549 cells. Conclusion: The O-OA-L, as a promising agent, can target actively the lesion site with safe and high-efficiency pattern. [ABSTRACT FROM AUTHOR]

Stimuli-responsive drug delivery and release have a great significance in cancer therapy. Herein, a multifunctional responsive drug carrier was designed and developed by loading resveratrol (Res) in chitosan (CTS) modified liposomes, and coated by gold nanoshells (GNS@CTS@Res-lips). The resultant GNS@CTS@Res-lips possess broad near-infrared (NIR) absorbance, high capability, stability, and also high photothermal conversion ability for efficient photothermal therapy (PTT) applications. In addition, the GNS@CTS@Res-lips exhibit the on-demand pH/photothermal-sensitive drug release, and a high loading capacity of Res. Under NIR laser irradiation, the drug delivery system could significantly enhance the cellular uptake of drugs. More importantly, compared to the single chemotherapy or PTT, the carriers with NIR irradiation displayed a higher therapeutic effect for HeLa cells. Therefore, the GNS@CTS@Res-lips with a combination of chemotherapy and PTT will show great potential for application in cancer therapy. [ABSTRACT FROM AUTHOR]

Immunotherapy stands as a groundbreaking strategy for cancer treatment, due to its ability to precisely and safely detect and eradicate tumors. However, the efficacy of immunotherapy is often limited by tumor autophagy, a natural defense mechanism that tumors exploit to resist immune attacks. Herein, we introduce a spatiotemporally controlled method to modulate tumor autophagy via sonocatalysis, aiming to improve immunotherapeutic outcomes. Specifically, we synthesized a tumor-targeting nanocatalyst based on a semiconductor heterojunction composed of Barium Titanate (BTO), Black Phosphorus (BP) integrated with Hyaluronic Acid (HA), referred to as BTO/BP-HA. Compared to traditional catalysts, the heterojunction structure enhances energy band bending and rapid electron-hole separation under ultrasonic stimulation, splitting water to generate H 2 . This promotes tumor cell apoptosis by inhibiting mitochondrial respiration and induces immunogenic cell death, triggering immune responses to eliminate tumor cells. However, the concurrent activation of autophagy mitigates the cytotoxic effectiveness of nanocatalysts. Within the nanocatalyst, BP undergoes lysosomal degradation to generate PO 4 3- , which subsequently interacts with H + to generate a conjugated acidic anion, increasing the lysosomal pH. This research ingeniously combines sonocatalysis with tumor autophagy, disrupting the activity of acidic hydrolases to inhibit autophagy, thereby enhancing the immune response and improving the effectiveness of immunotherapy.

High level of C (ROS) within the tumor microenvironment (TME) not only damage tumor cells but also diminish the efficacy of immunogenic cell death (ICD) and the activity of tumor-infiltrating T lymphocytes, thereby limiting the effectiveness of immunotherapy. Therefore, precise modulation of ROS level is crucial to effectively eliminate tumor cells and activate ICD-induced immunotherapy. Here, an intelligent yolk shell nanoplatform (SPCCM) that features calcium carbonate shells capable of decomposing under acidic TME conditions, thereby releasing the natural antioxidant proanthocyanidins (PAs) and the photosensitizer Ce6 is designed. PAs scavenge ROS within tumors, extending the survival time of T lymphocytes, while Ce6, as an ICD inducer, generates high ROS concentrations upon laser irradiation, thus reaching the toxic threshold within tumor cells and inducing apoptosis. The resulting apoptotic cells serve as tumor-associated antigens, promoting dendritic cells (DCs) maturation, and activating ICD. By effectively neutralizing ROS in the TME, PAs sustainably reduce ROS level, thereby enhancing DCs activation and restoring antitumor immune cell activity suppressed by ROS (resulting in an eightfold increase in DCs activation). This study demonstrates effective synergistic effects between photodynamic therapy and immunotherapy by precisely modulating ROS level., (© 2024 Wiley‐VCH GmbH.)

In oncological nanomedicine, overcoming the dual-phase high interstitial pressure in the tumor microenvironment is pivotal for enhancing the penetration and efficacy of nanotherapeutics. The elevated tumor interstitial solid pressure (TISP) is largely attributed to the overaccumulation of collagen in the extracellular matrix, while the increased tumor interstitial fluid pressure (TIFP) stems from the accumulation of fluid due to the aberrant vascular architecture. In this context, metal-organic frameworks (MOFs) with catalytic efficiency have shown potential in degrading tumor interstitial components, thereby reducing interstitial pressure. However, the potential biotoxicity of the organic components of MOFs limits their clinical translation. To circumvent this, a MOF-like photocatalytic nanozyme, RPC@M, using naturally derived cobalt phytate (CoPA) and resveratrol (Res) is developed. This nanozyme not only facilitates the decomposition of water in the tumor interstitium under photoactivation to reduce TIFP, but also generates an abundance of reactive oxygen species through its peroxidase-like activity to exert cytotoxic effects on tumor cells. Moreover, Res contributes to the reduction of collagen deposition, thereby lowering TISP. The concurrent diminution of both TISP and TIFP by RPC@M leads to enhanced tumor penetration and potent antitumor activity, presenting an innovative approach in constructing tumor therapeutic nanozymes from natural products., (© 2024 Wiley‐VCH GmbH.)

Precision drug delivery and multimodal synergistic therapy are crucial in treating diverse ailments, such as cancer, tissue damage, and degenerative diseases. Electrodes that emit electric pulses have proven effective in enhancing molecule release and permeability in drug delivery systems. Moreover, the physiological electrical microenvironment plays a vital role in regulating biological functions and triggering action potentials in neural and muscular tissues. Due to their unique noncentrosymmetric structures, many 2D materials exhibit outstanding piezoelectric performance, generating positive and negative charges under mechanical forces. This ability facilitates precise drug targeting and ensures high stimulus responsiveness, thereby controlling cellular destinies. Additionally, the abundant active sites within piezoelectric 2D materials facilitate efficient catalysis through piezochemical coupling, offering multimodal synergistic therapeutic strategies. However, the full potential of piezoelectric 2D nanomaterials in drug delivery system design remains underexplored due to research gaps. In this context, the current applications of piezoelectric 2D materials in disease management are summarized in this review, and the development of drug delivery systems influenced by these materials is forecast.