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Atherosclerosis is a chronic inflammatory disease in which atheromatous plaque long-termly accumulates and obstructs the intima of medium and large arteries, causing first severe stenosis and blood flow disorders, and then ischemia and hypoxia in tissues and organs. Nanomedicines have received widespread attention for their unique advantages over conventional drugs in the treatment of atherosclerosis. This article detailedly reviews several nanoparticle- and exosome-based targeted drug delivery systems in anti-atherosclerosis research, briefly describes the synthesis of representative nanomaterials, analyses their targeting properties and outlines the benefits and inherent challenges of nanomedicines. Despite the challenges that need to be addressed and refined, nanoparticles and exosomes used as drug delivery vehiclesin treatments for atherosclerosis hold great promise and are expected to have wider clinical applications.

While an increasing literature on multilingualism addresses the key role of language in access to social resources, including crisis communication, little attention has been paid to practices of English-mediated multilingualism. Based on semi-structured interviews with 10 international students from South Asia and Southeast Asia receiving their higher education in China, the study reveals what language-related challenges international students encounter, how they mobilize their multilingual resources to enhance their access to crisis communication and build a shared community, and how their multilingual competences are valorized and enacted in the shifting paradigm of the China-oriented new economy addressing mutual accountability in South-South cooperation. The study suggests that English-mediated multilingualism in China fails to bridge the needs of international students of diverse backgrounds. The study also calls attention to the shifting paradigm of multilingual studies and the necessity of addressing the real world problems of health communication in a diverse context.

Due to the demand for temporary rapid grid connection in renewable energy power plants, the topology structure of T-connected power lines has been widely used in the power grid. In this three-terminal system, fault localization is difficult because of traditional impedance-based or traveling wave-based fault localization methods; the three-terminal data should be synchronized and communicated. Since different terminal assets belong to different enterprises, it is actually difficult to maintain good synchronization between them. Therefore, in practical applications, the fault location of T-connected power lines often fails. This article proposes a single terminal fault location method for a T-connection power line to address this issue. It is based on the fact that the local topology of the T-connected power line in the healthy phase remains unchanged during the fault-clearing process. It utilizes the sequential current and voltage data changes generated by the sequential tripping ping emitted by the circuit breaker from different terminals to describe the constant topology of the healthy phase as an equation and calculates the accurate fault location after solving the equation. The Levenberg–Marquardt algorithm was used to calculate fault distance and transition resistance, and the effectiveness of this method was verified through simulation. [ABSTRACT FROM AUTHOR]

At present, conventional periodontal treatment cannot achieve complete and effective periodontal tissue regeneration. Cell sheet technology (CST) is a kind of cell transplantation method without scaffold material that can maintain complete extracellular matrix, important ion channels of cells, growth factor receptors, etc., and ensure the interaction between cells and the extracellular matrix. In this paper, the application and research progress of the cell sheet in the field of periodontal tissue regeneration are reviewed. Different types of seed cells can be prepared into monolayer cell sheet, multilayer cell sheet, cell sheet fragments and cell sheet polymers. Among them, the monalayer cell sheet is easily damaged and requires high deoperator; the multilayer cell sheet shows improved mechanical properties, but its thickness needs to be controlled to avoid cell necrosis. The cell sheet fragment can be used in the narrow space between the alveolar bone and root cementum to reduce the difficulty of operation and improve the mechanical properties of the cell sheet. Cell sheet polymers are three-dimensional structures that can provide strong mechanical support and improve the stability of the cell sheet, but the stability of their biological activity needs to be further improved. In methods for construction of the cell sheet, the antifibrosis and antiangiogenesis properties of the amniotic sheet have shown that this structure is suitable as the matrix of cell culture; the method of using a temperature-sensitive culture dish is simple and easy; continuous induction with vitamin C can retain some important proteins on the cell surface; and the magnetic tissue engineering method can increase cell adhesion and easily form a stable cell sheet. The above methods have their own characteristics. In clinical applications, monolayer cell sheet is mainly used for direct transplantation to the receiving site to construct periodontal tissue; multilayer cell sheet of the same or different species overlap and are then transplanted to the receiving site; and multilayer cell sheet of the same kind are wrapped with scaffold material and then transplanted to the receiving site to construct a three-dimensional structure. Overall, cell sheet technology has shown good potential in periodontal tissue regeneration.

Circuit breakers on the filter bank branches in converter stations are vulnerable to contact wear and mechanical deterioration caused by frequent operations, which can lead to circuit breaker breakdowns and explosions. It is imperative to conduct research on the early detection of abnormal states in circuit breakers. Existing electrical quantity-based detection methods are constrained by a priori assumptions, and their measurement methods are susceptible to interference, leading to misjudgments. To address this issue, this paper examines the influence of changes in critical breakdown field strength and contact spacing on circuit breaker operation states. It also proposes a technical scheme that employs breakdown current values to comprehensively characterize circuit breaker operation states, replacing the use of critical breakdown field strength and contact spacing. An early detection method for abnormal circuit breaker states based on a sequence of breakdown current ratios at different times is proposed, and its effectiveness is verified through simulation and field recording data. [ABSTRACT FROM AUTHOR]

Under the current trend of power electronics in energy systems, a high percentage of renewable energy transports clean energy to the grid through grid-connected inverters. The pulse-width modulation (PWM) technique brings high-order harmonics near to the switching frequency, and LCL filters with low-pass characteristics become the common choice for grid-connected inverters. However, the low-order harmonics caused by nonideal switching characteristics are difficult to filter out, and the new resonance point introduced by the LCL filter causes a security problem for the energy systems. Firstly, the generation mechanism of the 6 k ± 1 order harmonic and high-frequency resonance from a PV grid-connected inverter is analyzed. Then, a virtual resistor is constructed by the active damping method to absorb the resonant component. Meanwhile, this paper also presents an adaptive modulation voltage compensation method to decrease the low-order harmonics. Finally, the actual measured data of user photovoltaic (PV) and multiple comparative simulations verify these theories. Simulation results show that the proposed coordinated control algorithm reduces the peak of the resonance point, and the rate of low-order harmonics mitigation is more than 50%. The proposed method is suitable for various operating conditions. [ABSTRACT FROM AUTHOR]