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Silicon oxide (SiOx, 0 < x ≤ 2) has been recognized as a prominent anode material in lithium‐ion batteries and sodium‐ion batteries due to its high theoretical capacity, suitable electrochemical potential, and earth abundance. However, it is intrinsically poor electronic conductivity and excessive volume expansion during potassiation/depotassiation process hinder its application in potassium‐ion batteries. Herein, we reported a hierarchical porous C/SiOx potassium‐ion batteries anode using lignite as raw material via a one‐step carbonization and activation method. The amorphous C skeleton around SiOx particles can effectively buffer the volume expansion, and improve the ionic/electronic conductivity and structural integrity, achieving outstanding rate capability and cyclability. As expected, the obtained C/SiOx composite delivers a superb specific capacity of 370 mAh g−1 at 0.1 A g−1 after 100 cycles as well as a highly reversible capacity of 208 mAh g−1 after 1200 cycles at 1.0 A g−1. Moreover, the potassium ion storage mechanism of C/SiOx electrodes was investigated by ex‐situ X‐ray diffraction and transmission electron microscopy, revealing the formation of reversible products of K6.8Si45.3 and K4SiO4, accompanied by generation of irreversible K2O after the first cycle. This work sheds light on designing low‐cost Si‐based anode materials for high‐performance potassium‐ion batteries and beyond. [ABSTRACT FROM AUTHOR]

As the next generation of green power system, smart grids have gradually enhanced the operation efficiency of power system. Meanwhile, the application of communication and intelligent technologies make the power grid more vulnerable to the emerging cyber‐physical attacks, such as the false data injection attack (FDIA). Particularly, the deception property of the FDIA on the output measurement estimation can fool the current security mechanism without triggering an alarm. Motivated by this problem, this paper aims at developing a novel detection and recovery mechanism against FDIA in smart grid. Based on the established state space grid model derived from the three‐phase sinusoidal voltage equations, an improved principal component analysis (PCA)‐based detection method is proposed. By introducing the mathematical transformation principle method, the detection performance such as detection rate and false positive rate can be improved. To keep the stable running of power system, a genetic optimization algorithm‐based linear quadratic regulator (LQR) defense method is developed. In addition, to improve the response performance to external attacks, an artificial intelligence method named genetic optimization algorithm is introduced to optimize the robust performance of the proposed defense method. Finally, the simulation results on the IEEE 6‐bus and 118‐bus grid system demonstrate the superiority of the proposed genetic algorithm optimization‐based LQR defense method. [ABSTRACT FROM AUTHOR]

The increasing number of regions have begun to construct age‐friendly medical institutions to further promote the "successful aging" of the elderly in mainland China. This study deeply analyzes the development status of age‐friendly medical institutions abroad and describes the policies, research, evaluation, and certification of different countries. This study focuses on the current construction status of age‐friendly medical institutions in mainland China. With the issuing of several national policies, mainland China has established a top‐down system for the construction of age‐friendly medical institutions, which has been gradually implemented in the actions of medical institutions. On the whole, the goal and evaluation standard are clear and the action is rapid. However, it also faces many challenges and problems. This study puts forward various suggestions for the construction of age‐friendly medical institutions, such as increasing manpower and financial investment and carrying out evidence‐based research. In particular, we should pay attention to promoting a bottom‐up construction system, understand the actual needs of the elderly, pay attention to the personal experience of the elderly, and fully mobilize the active and full participation of the whole society. [ABSTRACT FROM AUTHOR]

Aims: To determine the clinicopathological features of pulmonary sclerosing pneumocytoma (PSP) with spindle cells and in cases with positive detection of PSP cells in the lymph nodes. Methods and results: This article report the clinical, histological and immunohistochemical features of PSP with dense spindle stromal cells in five patients (including one case with lymph node metastasis) and PSP accompanied by positive nodes in two patients out of 239 cases diagnosed at our institution between 2007 and 2019. The literature on PSP was also reviewed in detail. Six patients were female, and one (with a positive node) was male; their average age was 53 years. Thoracic imaging revealed solid tumours with clear borders and a uniform texture in six patients, but one patient had a lobulated tumour with uneven densities. All tumours were unifocal, and they had an average size of 31 mm. Tumours from five cases were mainly composed of solid regions of diffuse spindle cells rather than polygonal cells. Immunohistochemical staining demonstrated that thyroid transcription factor‐1, vimentin, epithelial membrane antigen (weak) and oestrogen receptor (partial) were expressed in spindle cells. The average follow‐up time was 31 months. Two of the 234 PSP cases for which adequate data were available had positive nodes (metastasis rate: 0.8%), and one of the five patients with PSP with spindle cells showed lymph node metastasis (metastasis rate: 20%). In addition, stromal cells were found to be predominant at metastatic sites. Conclusions: Spindle cells are present among the stromal cells of PSP, and not all of them are round cells. PSP patients with spindle cells or male patients may be more prone to metastasis than others. [ABSTRACT FROM AUTHOR]

This letter presents a robust active contour model driven by the local threshold preprocessing fitting energies to actualize fast segmentation of inhomogenous images. First, the local threshold preprocessing is carried out to compute two local intensity means. Second, these two means are sorted and serve as the local area fitting centres, which makes the contour move along the internal or external target boundaries. Finally, the above local area fitting centres are used to build the model's energy functional based on the symmetric cross entropy. Experimental results of the real inhomogenous images confirm that the presented model can segment inhomogenous images much faster and is robust to the setting up of the original contour. [ABSTRACT FROM AUTHOR]