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This study aims to employ a causal network model based on transfer entropy for the early warning of systemic risk in commodity markets. We analyzed the dynamic causal relationships of prices for 25 commodities related to China (including futures and spot prices of energy, industrial metals, precious metals, and agricultural products), validating the effect of the causal network structure among commodity markets on systemic risk. Our research results identified commodities and categories playing significant roles, revealing that industry and precious metal markets possess stronger market information transmission capabilities, with price fluctuations impacting a broader range and with greater force on other commodity markets. Under the influence of different types of crisis events, such as economic crises and the Russia–Ukraine conflict, the causal network structure among commodity markets exhibited distinct characteristics. The results of the effect of external shocks to the causal network structure of commodity markets on the entropy of systemic risk suggest that network structure indicators can warn of systemic risk. This article can assist investors and policymakers in managing systemic risk to avoid unexpected losses. [ABSTRACT FROM AUTHOR]

The biological world serves as a vast reservoir of inspiration for human innovation, particularly in the realm of robotics designed to navigate intricate granular environments. Among these creatures adept at burrowing, the mole stands out due to its exceptional body structure and unparalleled efficiency, surpassing most engineering burrowing systems. Consequently, the mole serves as an ideal model for designing highly efficient burrowing robots. This study introduces a mole‐inspired robot burrowing with forelimbs, specifically designed for planetary soil exploration. By closely examining the distinctive body morphology of moles, a forelimb burrowing mechanism is devised through biomimetic mapping, and its kinematics is thoroughly analyzed. A robot prototype is developed and an experimental setup is constructed to evaluate its burrowing performance. A series of tests are conducted to assess the capabilities of the robot, including forelimb burrowing, robot crawling, and robot burrowing. The results demonstrate that the proposed mole‐inspired burrowing robot is capable of crawling and burrowing to a certain depth using its forelimbs. Although it exhibits some upward displacement, this issue can be mitigated by modifying the head configuration and adjusting the forelimb posture to effectively overcome the vertical stress and lift force exerted by granular soils due to intensity gradient. [ABSTRACT FROM AUTHOR]

Due to the large thermal resistance on the airside of the air-cooled heat exchangers, it is necessary to improve heat transfer performance and reduce flow resistance by improving the fin structure. In this paper, partially serrated finned tube bank was proposed and numerically investigated. The experimental system of finned tube bank was built to verify the correctness of the numerical simulation. The finned tube bank is twisted and serrated on the windward side to enhance heat transfer. Moreover, the non-grooved sector region on the leeward side reduces the flow resistance and improves the temperature uniformity of the fins. The effects of fin twisting of the windward side and non-grooving angle of the leeward side were explored. Nusselt number and friction factor decrease as the leeward non-grooving sector region increases. The correlations of Nusselt number and friction factor were derived based on the simulation results of partially serrated twisted finned tube banks with 120° non-grooving region on the leeward side. Nusselt number, friction factor and comprehensive heat transfer coefficient of partially serrated twisted finned tube bank are 13.3%, 13.0% and 10.5% higher than that of annular finned tube bank with Reynolds number from 6200 to 20,600, respectively. [ABSTRACT FROM AUTHOR]

Purpose: This review was made to identify the risk factors for knee osteoarthritis (KOA) in middle-older aged (≥ 40 years), and to provide the newest evidence for the prevention of KOA. Method: Cohort study and case–control study of the risk factors of KOA was included from Pubmed, Web of Science, Ovid Technologies, China National Knowledge Infrastructure (CNKI), Chinese Science and Technology Periodical Database (VIP), Wanfang Database, SinoMed from their inceptions to July 2023. Two authors independently screened the literature and extracted data. Assessment of quality was implemented according to Agency for Healthcare Research and Quality (AHRQ) and Newcastle–Ottawa Quality Assessment Scale. Meta-analysis was performed using RevMan 5.3 software. Results: 3597 papers were identified from the seven databases and 29 papers containing 60,354 participants were included in this review. Meta-analysis was performed for 14 risk factors, and 7 of these were statistical significance (P < 0.05). The risk factors which were analyzed in this review included trauma history in knee (1.37 [95% CI 1.03–1.82], P = 0.030), body mass index (BMI) ≥ 24 kg/m2 (1.30 [95% CI 1.09–1.56], P = 0.004), gender (female) (1.04 [95% CI 1.00–1.09], P = 0.030), age ≥ 40 (1.02 [95% CI 1.01–1.03], P = 0.007), more exercise (0.75 [95% CI 0.62–0.91], P = 0.003), a high school education background (0.49 [95% CI 0.30–0.79], P = 0.003) and an university education background (0.22 [95% CI 0.06–0.86], P = 0.030). Conclusion: The risk factors analyzed in this review included trauma history in knee, overweight or obesity, gender (female), age ≥ 40 and the protective factors included more exercise and a high school or an university education background. [ABSTRACT FROM AUTHOR]

Rice adaptation to low temperatures involves changes in their genetic and physiological architecture, caused by complex and variable transcriptional regulatory networks to regulate between growth and stress resistance. Overwintering rice survives cold winter and germinates the following spring. The perennial and cold‐tolerant properties present great potential regarding rice breeding and food security. In this study, the cold‐tolerant overwintering cultivar rice, "glutinous rice 89‐1" (Gr 89‐1), and an indica cultivar rice, "R07," were placed at 4°C at the tillering stage and sampled at 0, 12, 24, and 96 h, and recovery 7 days. Physiological indicators of each sample were measured, and transcriptome analysis was performed. The results revealed that the overwintering cultivar rice Gr 89‐1 exhibited a pattern of physiological parameters consistent with the cold‐tolerant phenotype, less membrane damage accumulation and water loss with increasing duration of low temperature, and a stable increase in peroxidase activities, catalase activities, and soluble sugar content. Transcriptome analysis of two cultivars at 0, 12, and 24 h under 4°C revealed different gene expression patterns to low temperatures. Compared with R07, gene ontology terms of nuclear lumen, endomembrane system, organelle membrane, and envelope were enriched in Gr 89‐1, suggesting an alteration of membrane composition during cold acclimation. Specific upregulated transcription factors and cold‐tolerance regulators indicated a coordinated response between signal transduction, energy regulation, cell cycle, and circadian rhythm, which might help maintain cell homeostasis and improve Gr 89‐1 survival under cold stress. Two candidate genes OsETR3 and NAC78 were screened out, they significantly upregulated at 12 and 24 h of cold treatment in Gr 89‐1 and were higher than R07, and they were involved in cell wall remodeling and endoplasmic reticulum homeostasis under stress, respectively, which may relate to the cold‐tolerant trait of Gr 89‐1. [ABSTRACT FROM AUTHOR]