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To explore the risk factors of atrial fibrillation (AF) in patients with coronary heart disease (CHD), and to construct a risk prediction model. Methods: The participants in this case-control study were from the cardiovascular Department of Changzhou Affiliated Hospital of Nanjing University of Chinese Medicine from June 2016 to June 2023, and they were divided into AF group and non-AF group according to whether AF occurred during hospitalization. The clinical data of the two groups were compared by retrospective analysis. Multivariate Logistic regression analysis was used to investigate the risk factors of AF occurrence in CHD patients. The nomogram model was constructed with R 4.2.6 language "rms" package, and the model's differentiation, calibration and effectiveness were evaluated by drawing ROC curve, calibration curve and decision curve. Results: A total of 1258 patients with CHD were included, and they were divided into AF group (n=92) and non-AF group (n=1166) according to whether AF was complicated. Logistic regression analysis showed that age, coronary multiple branch lesion, history of heart failure, history of drinking, pulmonary hypertension, left atrial diameter, left ventricular end-diastolic diameter and diabetes mellitus were independent risk factors for the occurrence of AF in CHD patients (P < 0.05). The ROC curve showed that the AUC of this model was 0.956 (95% CI (0.916, 0.995)) and the consistency index was 0.966. The calibration curve of the model is close to the ideal curve. The analysis of decision curve shows that the prediction value of the model is better when the probability threshold of the model is 0.042~0.963. Conclusion: The nomogram model established in this study for predicting the risk of AF in patients with CHD has better predictive performance and has certain reference value for clinical identification of high-risk groups prone to AF in patients with CHD. [ABSTRACT FROM AUTHOR]

In this study, M-HMX-based PBX (M-HMX-PBX) and N-HMX-based PBX (N-HMX-PBX) were prepared by industrial micron-sized HMX (M-HMX) and nano-sized HMX (N-HMX) via solution-water suspension method, respectively. The critical electronic excitation energy (Ec) of M-HMX particle and N-HMX particles was calculated by combining with field emission scanning electron microscopy (FE-SEM) and Image Pro Plus (IPP) software. Meanwhile, the average critical electron excitation energy ( E C ‾ ) of the entire particle group was calculated. Those results shown that E C ‾ of N-HMX was higher than that of M-HMX, which indicated that the stability of N-HMX was better than that of M-HMX. In addition, the reaction activation energies (Ea) also indicated that N-HMX and N-HMX-PBX were more stable than M-HMX and M-HMX-PBX, which were calculated by the Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods. The above results explained the reasons for the high thermal decomposition stability of N-HMX-PBX from the micro and macro perspectives. And those provided theoretical basis for exploring the application of N-HMX in improving the thermal stability of HMX-PBX. [ABSTRACT FROM AUTHOR]

In this study, a novel nitrated bacterial cellulose/2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane/ammonium perchlorate nanoenergetic composite was successfully prepared by the sol–gel method and the freeze-drying technology. The structure and composition were characterised by means of scanning electron microscope, X-ray diffractometer and Fourier-transform infrared. The results demonstrated that the structure of the gel nanoparticles was granted with unique network cross-linked porous, wherein the hexaazaisowurtzitane and ammonium perchlorate nanoparticles were embedded and dispersed uniformly in the gel matrix. The thermal decomposition properties of composites were analysed by differential scanning calorimeter-thermogravimetric analysis, and the results revealed that the composites exhibited only two exothermal peaks which correspond to the nitrated bacterial cellulose/hexaazaisowurtzitane and ammonium perchlorate. In addition, the impact and friction sensitivities of composites were also performed and showed outstanding safety performance. Hence, this preparation strategy of nitrated bacterial cellulose-based nanocomposite energetic materials may provide promising application in high-performance and low-sensitivity propellants. [ABSTRACT FROM AUTHOR]

LiNi0.8Co0.15Al0.05O2 has attracted attention due to its high capacity and low cost. Herein, we report a method for the rapid and efficient preparation of NCA cathode materials using oxalic acid with freeze-drying techniques, and compare the differences of electrochemical properties for different metal concentrations. The solvent volatilization by liquid nitrogen freezing and freeze-drying techniques resulted in a more uniform mixing of metal ions while reducing the reaction time and energy consumption. The results characterized using X-ray diffraction revealed that the layered structure of the material was better and the cation mixing was lower when the metal ion concentration in the solution reached 0.15 mol L−1. The electrochemical data revealed an initial charge–discharge capacity of 195 mAh g−1 at 0.1 C, capacity retention of 88.75% for 100 cycles at 1 C, and a discharge capacity of 139.7 mAh g−1 at 5 C. In addition, the cyclic voltammetry and electrochemical impedance spectroscopy reflect the material has low electrode polarization and excellent lithium-ion diffusion coefficient. The initial material diffusion coefficient is 2.673 × 10 - 15 cm 2 S - 1 ; after 50 and 100 cycles, it is 6.040 × 10 - 16 cm 2 S - 1 10−16 cm2S−1 and 1.704 × 10 - 16 cm 2 S - 1 respectively. The results provide a new idea for the energy-efficient synthesis of LiNi0.8Co0.15Al0.05O2. [ABSTRACT FROM AUTHOR]

The fourth plenary session of the 19th CPC Central Committee interpreted the code of the 'governance of China' system, so strengthening the study of the socialist system with Chinese characteristics has become increasingly important. The river chief system is a river basin governance system with distinctive Chinese characteristics, but the existing research lacks in-depth and systematic studies on the proposition of how the river chief system was established. Based on this, this paper constructs a system interpretative framework based on its function, deep structure and mechanism conditions to conduct an in-depth study of this proposition. The research shows that: 1) In terms of function, with the rapid development of economy and society, China's river basin governance system has become increasingly difficult to meet the systematic requirements of water governance, resulting in problems such as the 'Nine Dragons Taming the Water'. Under this background, the river chief system as a connective mechanism emerged timely, which helps to deal with the dilemma of cross-organizational governance of river basin. 2) In terms of deep structure, China's national governance structure is characterized by 'party committee leadership, government responsibility, hierarchical management, and departmental division of labor'. In order to reduce the cost of horizontal cooperation ad integrate the forces of all parties, a problem-solving mechanism ad political and cultural tradition of 'leadership in command and high-level coordination' has been formed for a long time, which has to a great extent shaped the chief system design concept of 'controlling water pollution only after providing effective civil servant management, Providing effective civil servant management only after giving right incentives to motivate government officials'. 3) In terms of mechanism conditions, the introduction of the river chief system was the direct result of the pressure driven by the headline event of blue-green algae outbreak in Taihu Lake. The hierarchical structure of the communist party and government and the government official target management responsibility system have provided organizational coordination advantages and management control basis for its establishment and operation. Generally speaking, the river chief system was not only the result of the insufficient response of the river basin governance system, but also the result of the fusion of the traditional system advantages and the concept of green development. Since the river chief system was born in a crisis, it has been more dependent on the attention of local party and government leaders, so after its regularization, it is necessary to improve the relevant incentive system in order to form a long-term mechanism. [ABSTRACT FROM AUTHOR]