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With the advancement of radar technology toward multifunctionality and cognitive capabilities, traditional radar countermeasures are no longer sufficient to meet the demands of countering the advanced multifunctional radar (MFR) systems. Rapid and accurate generation of the optimal jamming strategy is one of the key technologies for efficiently completing radar countermeasures. To enhance the efficiency and accuracy of jamming policy generation, an efficient jamming policy generation method based on multi-timescale ensemble Q-learning (MTEQL) is proposed in this paper. First, the task of generating jamming strategies is framed as a Markov decision process (MDP) by constructing a countermeasure scenario between the jammer and radar, while analyzing the principle radar operation mode transitions. Then, multiple structure-dependent Markov environments are created based on the real-world adversarial interactions between jammers and radars. Q-learning algorithms are executed concurrently in these environments, and their results are merged through an adaptive weighting mechanism that utilizes the Jensen–Shannon divergence (JSD). Ultimately, a low-complexity and near-optimal jamming policy is derived. Simulation results indicate that the proposed method has superior jamming policy generation performance compared with the Q-learning algorithm, in terms of the short jamming decision-making time and low average strategy error rate. [ABSTRACT FROM AUTHOR]

In the last few decades, tear-based biosensors for continuous glucose monitoring (CGM) have provided new avenues for the diagnosis of diabetes. The tear CGMs constructed from nanomaterials have been extensively demonstrated by various research activities in this field and are gradually witnessing their most prosperous period. A timely and comprehensive review of the development of tear CGMs in a compartmentalized manner from a nanomaterials perspective would greatly broaden this area of research. However, to our knowledge, there is a lack of specialized reviews and comprehensive cohesive reports in this area. First, this paper describes the principles and development of electrochemical glucose sensors. Then, a comprehensive summary of various advanced nanomaterials recently reported for potential applications and construction strategies in tear CGMs is presented in a compartmentalized manner, focusing on sensing properties. Finally, the challenges, strategies, and perspectives used to design tear CGM materials are emphasized, providing valuable insights and guidance for the construction of tear CGMs from nanomaterials in the future. [ABSTRACT FROM AUTHOR]

Designing artificial nano-enzymes for scavenging reactive oxygen species (ROS) in chondrocytes (CHOs) is considered the most feasible pathway for the treatment of osteoarthritis (OA). However, the accumulation of ROS due to the amount of nano-enzymatic catalytic site exposure and insufficient oxygen supply seriously threatens the clinical application of this therapy. Although metal–organic framework (MOF) immobilization of artificial nano-enzymes to enhance active site exposure has been extensively studied, artificial nano-enzymes/MOFs for ROS scavenging in OA treatment are still lacking. In this study, a biocompatible lubricating hydrogel-loaded iron-doped zeolitic imidazolate framework-8 (Fe/ZIF-8/Gel) centrase was engineered to scavenge endogenous overexpressed ROS synergistically generating dissolved oxygen and enhancing sustained lubrication for CHOs as a ternary artificial nano-enzyme. This property enabled the nano-enzymatic hydrogels to mitigate OA hypoxia and inhibit oxidative stress damage successfully. Ternary strategy-based therapies show excellent cartilage repair in vivo. The experimental results suggest that nano-enzyme-enhanced lubricating hydrogels are a potentially effective OA treatment and a novel strategy. [ABSTRACT FROM AUTHOR]

Biotic exchanges between Taiwan and Mainland China have shaped the biodiversity and ecosystems of both regions. Exchanges from Mainland China to Taiwan have received more attention, mainly studied in terrestrial vertebrates, while the reverse direction and invertebrates have largely been overlooked. Here, we explore the dispersal events between these two regions based on the moths of three species groups of Obeidia, including Taiwan taxa and its relatives from mainland. We conducted mixed methods and analysis, including reconstructing a phylogenetic tree, estimating associated divergence times and inferring ancestral areas and source regions, to explore the phylogeographical structure and genetic pattern of three groups based on eight genes. Our results revealed a structure of three clades and every clade included at least one Taiwanese taxa and its closest relatives of mainland of China, and also served Taiwan as an important source region of two mainland taxa. Our study revealed various origin pattern and dispersal models on the basis of three species groups of Obeidia. Bi‐directional biotic exchange via a land bridge were found: four Taiwanese taxa originated from mainland, and two of them migrated back to mainland. Both eastern Himalayas and south China are important origin areas for Taiwan biota, and the dominant source region may need multiple insect cases to confirm. Our study also provided evidences for disjunct distribution from the perspective of insecta molecular phylogeny. [ABSTRACT FROM AUTHOR]

In repaired marine concrete structures, generally, an interface exists between old and new concrete, however, the influence of this interface on durability has yet not been well understood. In this study 18 reinforced concrete beams with new‐to‐old concrete interfaces (N–O interfaces) were designed to investigate chloride transport through a cracked interface. The effects of crack widths at the interface, concrete strain, and the chloride exposure time were considered, respectively. Results showed that the N–O interfaces having crack widths between 0 and 0.13 mm posed no significant impact on the chloride transport in the depth direction of the N–O interfaces, however when the crack width exceeded 0.13 mm, the chloride concentration gradually increased as the crack width increased. Chloride transport through the horizontal direction of the N–O interface was different between new and old concrete matrix when the crack width reached 0.18–0.20 mm. The surface layer with a range of 5–10 mm depth of concrete was sensitive to the variation of concrete strain, and the evolution of chloride concentration with concrete strain presented a logarithm relationship. Within the exposure period between 60 and 90 days, the increasing rate of chloride concentration was higher than that between 30 and 60 days. The study can provide some recommendations for repair of concrete elements exposed to a chloride‐laden exposure environment. [ABSTRACT FROM AUTHOR]

A facile one-step solvothermal method was developed to synthesize Ir-doped Co-based metal–organic framework (CoIr-MOF) nanoarrays as a bifunctional electrocatalyst for water–glucose co-electrolysis. It was demonstrated that in situ incorporation of a low-content of Ir cations could modulate the electronic structure of Co active centers and thus boost the electrocatalytic performance towards both the hydrogen evolution reaction and glucose-to-formate oxidation reaction. [ABSTRACT FROM AUTHOR]

How many species of life are there on Earth? This is a question that we want to know but cannot yet answer. Some scholars speculate that the number of species may reach 2.2 billion when considering cryptic diversity and that each morphology‐based insect species may contain an average of 3.1 cryptic species. With nearly two million described species, such high estimates of cryptic diversity would suggest that cryptic species are widespread. The development of molecular species delimitation has led to the discovery of a large number of cryptic species, and cryptic biodiversity has gradually entered our field of vision and attracted more attention. This paper introduces the concept of cryptic species, how they evolve, and methods by which they may be discovered and confirmed, and provides theoretical and methodological guidance for the study of hidden species. A workflow of how to confirm cryptic species is provided. In addition, the importance and reliability of multi‐evidence‐based integrated taxonomy are reaffirmed as a way to better standardize decision‐making processes. Special focus on cryptic diversity and increased funding for taxonomy is needed to ensure that cryptic species in hyperdiverse groups are discoverable and described. An increased focus on cryptic species in the future will naturally arise as more difficult groups are studied, and thereby, we may finally better understand the rules governing the evolution and maintenance of cryptic biodiversity. [ABSTRACT FROM AUTHOR]

A simplified axisymmetric model of a transfemoral osseointegration implant was used to investigate the influence of the contact condition at the bone-implant interface on the vibrational response. The experimental setup allowed the degree of implant tightness to be controlled using a circumferential compression device affixed to the bone. Diametrically placed sensors allowed torsional modes to be distinguished from flexural modes. The results showed that the structural resonant frequencies did not shift significantly with tightness levels. The first torsional mode of vibration was found to be particularly sensitive to interface loosening. Harmonics in the vibrational response became prominent when the amplitude of the applied torque increased beyond a critical level. The torque level at which the third harmonic begins to rise correlated with implant criticality, suggesting a potential strategy for early detection of implant loosening based on monitoring the amplitude of the third harmonic of the torsional mode.

The dynamic changes in volatile organic compounds (VOCs), reducing sugars, and amino acids of Dictyophora rubrovalvata (DR) at various drying temperatures were analyzed using GC-IMS, HPLC, and LC-MS. Orthogonal partial least squares discriminant analysis (OPLS-DA) combined with VOCs indicated that drying temperature of 80 °C was optimal. Variable importance in the projection (VIP) and relative odor activity value (ROAV) were employed to identify 22 key VOCs. The findings suggested that esters played a predominant role among the VOCs. Pearson correlation analysis revealed that serine (Ser), glutamine (Gln), lysine (Lys), alanine (Ala), threonine (Thr), glutamic acid (Glu), asparagine (Asn), ribose, and glucose were closely associated with the formation of esters, aldehydes, ketones, pyrimidines, and pyrazines. In conclusion, this study laid a foundational theory for elucidating the characteristics aroma substances and their production pathways, providing a valuable reference for analysing the flavor characteristics of DR., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)