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By following the encrypted communication proposed by IEC 62351-3 and the identity authentication technology by IEC 62351-4， the paper carries out research on role-based access control technology on the theoretical basis of IEC 62351-8. This technology preassigns a role to each client communication device in the communication link according to actual applications. It takes the digital certificate for its secure communication as a carrier to expand the access token that forms the role. The server device recognizes and extracts the role of the client from the digital certificate used by the client in secure communication and grants the client corresponding access permissions according to the preset mapping of roles and permissions to realize the role-based access control function. The purpose of hierarchical and sub-authorized access to IEC 61850 communication has been achieved. This technology improves the controllability of remote operation of power system equipment and has been applied in substations.

The display dynamics software is used to numerically simulate the punching process and explore the fracture of coal and rock under the impact of high-pressure water jets. We analyze the process and mechanism of cutting holes when the jet water column impacts coal and rock with or without confining pressure, and demonstrate the process that the coal and rock mass is subjected to tensile and shear forces to cause horizontal and vertical cracks to form and gradually extend into a crack network. The research results show that when the water jet impacts the coal and rock to form pores, it will form fissures for gas migration in the surrounding coal and rock, and the pore-forming damage range is affected by the confining pressure. When the jet parameters are constant, the confining pressure will hinder the expansion of the hole depth and pore size, but will further expand the development range of the surrounding fissures, and the expansion range will increase by about 40% under the action of the 20 MPa confining pressure.

If truth is absolute, how is it possible that people can argue for or against it? If truth is not absolute, on what is our existence predicated? Plato and Isocrates, two contemporaries in Classical Athens, took very different stands on the age-old problem of truth and the rhetorical manipulation of it. A close examination of Platonic dialogues and Isocrates’ speeches reveals that they had different understandings of the concept and purpose of truth. This fundamental divergence caused Plato and Isocrates to have disparate notions of rhetoric and even “philosophy”. Accordingly, they devised drastically different educational programs suited to their respective visions of truth and rhetoric, attempting to realize their competing ideals by means of pedagogy.

In China, winning the battle for blue skies is a focal point of the central government's environmental governance efforts. Public evaluations provide validity and legitimacy to the Chinese government's top-level design for environmental governance. This study utilizes data from two waves of the Chinese General Social Survey (CGSS) conducted in 2013 and 2021, paired with objective air quality data, to conduct a longitudinal analysis of public evaluation of central government environmental governance in China. Furthermore, it explores the relationships between perceived air pollution, objective air quality, environmental knowledge, and public assessment of central government environmental performance. The findings indicate the following: (1) Over the past decade, there has been a noticeable improvement in air quality in China, leading to a significant enhancement in public perception of the central government's environmental performance. (2) Subjective perceptions of air pollution have a significant negative impact on evaluations of the central government, whereas objective environmental governance measures do not exhibit significant effects. (3) Environmental knowledge plays a negative moderating role in the relationship between perceived air pollution and public assessment of central government environmental performance; individuals with higher levels of environmental knowledge tend to express greater dissatisfaction with the central government's environmental performance upon perceiving air pollution. These research findings offer valuable insights for informing the formulation of environmental governance policies by the central government of China and provide lessons for other developing and highly polluting countries. [ABSTRACT FROM AUTHOR]

Nano-hydroxyapatite (n-HA) is the main inorganic component of natural bone, which has been widely used as a reinforcing filler for polymers in bone materials, and it can promote cell adhesion, proliferation, and differentiation. It can also produce interactions between cells and material surfaces through selective protein adsorption and has therefore always been a research hotspot in orthopedic materials. However, n-HA nano-particles are inherently easy to agglomerate and difficult to disperse evenly in the polymer. In addition, there are differences in trace elements between n-HA nano-particles and biological apatite, so the biological activity needs to be improved, and the slow degradation in vivo, which has seriously hindered the application of n-HA in bone fields, is unacceptable. Therefore, the modification of n-HA has been extensively reported in the literature. This article reviewed the physical modification and various chemical modification methods of n-HA in recent years, as well as their modification effects. In particular, various chemical modification methods and their modification effects were reviewed in detail. Finally, a summary and suggestions for the modification of n-HA were proposed, which would provide significant reference for achieving high-performance n-HA in biomedical applications. [ABSTRACT FROM AUTHOR]

Despite a standardized diagnostic examination, cancer of unknown primary (CUP) is a rare metastatic malignancy with an unidentified tissue of origin (TOO). Patients diagnosed with CUP are typically treated with empiric chemotherapy, although their prognosis is worse than those with metastatic cancer of a known origin. TOO identification of CUP has been employed in precision medicine, and subsequent site-specific therapy is clinically helpful. For example, molecular profiling, including genomic profiling, gene expression profiling, epigenetics and proteins, has facilitated TOO identification. Moreover, machine learning has improved identification accuracy, and non-invasive methods, such as liquid biopsy and image omics, are gaining momentum. However, the heterogeneity in prediction accuracy, sample requirements and technical fundamentals among the various techniques is noteworthy. Accordingly, we systematically reviewed the development and limitations of novel TOO identification methods, compared their pros and cons and assessed their potential clinical usefulness. Our study may help patients shift from empirical to customized care and improve their prognoses. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS), which is a common and aggressive primary bone malignancy, occurs mainly in children and adolescent. Long noncoding RNAs (lncRNAs) are reported to play a pivotal role in various cancers. Here, we found that the lncRNA HOTAIRM1 is upregulated in OS cells and tissues. A set of functional experiments suggested that HOTAIRM1 knockdown attenuated the proliferation and stimulated the apoptosis of OS cells. A subsequent mechanistic study revealed that HOTAIRM1 functions as a competing endogenous RNA to elevate ras homologue enriched in brain (Rheb) expression by sponging miR‐664b‐3p. Immediately afterward, upregulated Rheb facilitates proliferation and suppresses apoptosis by promoting the mTOR pathway‐mediated Warburg effect in OS. In summary, our findings demonstrated that HOTAIRM1 promotes the proliferation and suppresses the apoptosis of OS cells by enhancing the Warburg effect via the miR‐664b‐3p/Rheb/mTOR axis. Understanding the underlying mechanisms and targeting the HOTAIRM1/miR‐664b‐3p/Rheb/mTOR axis are essential for OS clinical treatment. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is the most common primary malignant neoplasm of the bone. Recent studies have indicated that the inhibitory effects of microRNA (miR)‐324‐3p could affect the development of numerous cancers. However, its biological roles and underlying mechanisms in OS progression remain unexplored. In this study, miR‐324‐3p expression was markedly reduced in OS cell lines and tissues. Functionally, miR‐324‐3p overexpression suppressed OS progression and was involved in the Warburg effect. Mechanistically, miR‐324‐3p negatively regulated phosphoglycerate mutase 1 (PGAM1) expression by targeting its 3′‐UTR. Moreover, high expression of PGAM1 promoted OS progression and aerobic glycolysis, which were associated with inferior overall survival in patients with OS. Notably, the tumor suppressor functions of miR‐324‐3p were partially recovered by PGAM1 overexpression. In summary, the miR‐324‐3p/PGAM1 axis plays an important role in regulating OS progression by controlling the Warburg effect. Our results provide mechanistic insights into the function of miR‐324‐3p in glucose metabolism and subsequently on the progression of OS. Targeting the miR‐324‐3p/PGAM1 axis could be a promising molecular strategy for the treatment of OS. [ABSTRACT FROM AUTHOR]

The conventional design of wireless communication systems typically relies on established mathematical models that capture the characteristics of different communication modules. Unfortunately, such design cannot be easily and directly applied to future wireless networks, which will be characterized by large-scale ultra-dense networks whose design complexity scales exponentially with the network size. Furthermore, such networks will vary dynamically in a significant way, which makes it intractable to develop comprehensive analytical models. Recently, deep learning-based approaches have emerged as potential alternatives for designing complex and dynamic wireless systems. However, existing learning-based methods have limited capabilities to scale with the problem size and to generalize with varying network settings. In this paper, we propose a scalable and generalizable neural calibration framework for future wireless system design, where a neural network is adopted to calibrate the input of conventional model-based algorithms. Specifically, the backbone of a traditional time-efficient algorithm is integrated with deep neural networks to achieve a high computational efficiency, while enjoying enhanced performance. The permutation equivariance property, carried out by the topological structure of wireless systems, is furthermore utilized to develop a generalizable neural network architecture. The proposed neural calibration framework is applied to solve challenging resource management problems in massive multiple-input multiple-output (MIMO) systems. Simulation results will show that the proposed neural calibration approach enjoys significantly improved scalability and generalization compared with the existing learning-based methods. [ABSTRACT FROM AUTHOR]

The role of respiratory tract microbes and the relationship between respiratory tract and gut microbiomes in coronavirus disease 2019 (COVID‐19) remain uncertain. Here, the metagenomes of sputum and fecal samples from 66 patients with COVID‐19 at three stages of disease progression are sequenced. Respiratory tract, gut microbiome, and peripheral blood mononuclear cell (PBMC) samples are analyzed to compare the gut and respiratory tract microbiota of intensive care unit (ICU) and non‐ICU (nICU) patients and determine relationships between respiratory tract microbiome and immune response. In the respiratory tract, significantly fewer Streptococcus, Actinomyces, Atopobium, and Bacteroides are found in ICU than in nICU patients, while Enterococcus and Candida increase. In the gut, significantly fewer Bacteroides are found in ICU patients, while Enterococcus increases. Significant positive correlations exist between relative microbiota abundances in the respiratory tract and gut. Defensin‐related pathways in PBMCs are enhanced, and respiratory tract Streptococcus is reduced in patients with COVID‐19. A respiratory tract–gut microbiota model identifies respiratory tract Streptococcus and Atopobium as the most prominent biomarkers distinguishing between ICU and nICU patients. The findings provide insight into the respiratory tract and gut microbial dynamics during COVID‐19 progression, considering disease severity, potentially contributing to diagnosis, and treatment strategies. [ABSTRACT FROM AUTHOR]