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The implantable cardiac defibrillator (ICD) is common for the management of nonischemic cardiomyopathy (NICM). Mortality is a crucial issue for patients with NICM. We can understand the mortality events of ICD versus medicine treatment via a systemic review and meta-analysis of randomized clinical trials. The comparison between ICD treatment and medicine treatment was performed to find if the ICD treatment can be associated with lower relative risk and hazard ratio of mortality than the medicine treatment. In addition, the different kinds of mortality events were analyzed for the ICD treatment. After a restricted selection, 9 studies with a total of 4001 NICM patients were enrolled. The focused outcome was the events of all-cause mortality, sudden cardiac death, and cardiovascular death. The results showed that ICD treatment might be associated with lower relative risk and hazard ratio of all-cause mortality and sudden cardiac death. However, the relative risk and hazard ratio of cardiovascular mortality was not significantly different between ICD treatment and medicine treatment. In the current meta-analysis, the ICD treatment might show a lower relative risk and hazard ratio of all-cause mortality and sudden cardiac death when compared with medicine treatment. However, no significant differences were observed in cardiovascular mortality between ICD and medicine treatment.

Endothelial dysfunction, and the differentiation of smooth muscle cells (SMCs) into proliferative, secretory phenotypes, are two major pathophysiological processes in atherosclerosis. SMCs have the potential to recruit macrophages in atherosclerotic plaques, in which macrophages drive inflammatory responses. In this study, we found that microRNA-503-5p (miR-503-5p) was enriched in either extracellular vesicles (EVs), secreted by oxidized low-density lipoprotein-treated macrophages, or the EVs from peripheral blood mononuclear cells of atherosclerosis patients. miR-503-5p was transferred intercellularly from macrophages to the co-cultured human coronary artery endothelial cells (HCAECs) and HCASMCs via EVs, thus reducing the proliferative and angiogenic abilities of HCAECs and accelerating the proliferative and migrating abilities of HCASMCs. Smad family members 1, 2 and 7 were negatively regulated by miR-503-5p in HCAECs and HCASMCs. miR-503-5p was verified as an enhancer of inflammatory cytokines and adhesion molecules released by macrophages, in part via the down-regulation of smad family members 1, 2 and 7. The inhibition of miR-503-5p by lentivirus reduced atherosclerotic lesion formations in the aorta of atherosclerotic mice. Our work demonstrated a miR-503-5p- and EV-mediated mechanism for macrophage communication with HCAECs and HCASMCs in atherosclerosis. miR-503-5p is pro-atherosclerotic stimuli that may be a therapeutic target for atherosclerosis treatment.

The main purpose of the paper is to present an approach to account for the mechanism of bursting oscillations occurring in the systems with multiple periodic excitations. Since the traditional slow-fast analysis method can be used only for the systems with two scales in time domain, when there exists an order gap between the exciting frequencies and the natural frequency, how to explore the mechanism of the complicated dynamics remains an open problem, especially for the case when two exciting terms exist. To explain our approach, a relative simple Duffing’s oscillator with two external periodic excitations is introduced as an example. For the case when one exciting frequency is integer times of the other exciting frequency, by employing Moivre’s equation, the two exciting terms can be transformed into the functions of one basic periodic exciting term. Regarding the basic periodic exciting term as a slow-varying parameter, the two exciting terms can be changed into the functions of the slow-varying parameter, based on which the whole model can be transformed into a generalized autonomous system with one slow-varying parameter. Equilibrium branches as well as the related bifurcations of the generalized autonomous system can be derived with the variations of the amplitudes of the two excitations, which describes the relationship between the state variables of the generalized autonomous system and the slow-varying parameter. Considering the slow-varying parameter as a generalized state variable, one may obtain the so-called transformed phase portraits, which present the relationship between the state variable and the slow-varying parameter. The bifurcation mechanism of the mixed oscillations can be obtained by overlapping the equilibrium branches and the transformed phase portraits. Upon the approach, different types of bursting oscillations are presented. It is pointed that when the trajectory moves almost strictly along the segments of the stable equilibrium branches to the fold bifurcation points, jumping phenomena to other stable equilibrium segments can be observed, leading to the repetitive spiking oscillations, which can be approximated by the transient procedure from the bifurcation points to the stable equilibrium segments. Furthermore, because of the distributions of stable segments on the equilibrium branches of the generalized autonomous system may vary with the exciting amplitudes, the forms of bursting oscillations may change. When more fold bifurcations involve in the bursting attractors, more forms of quiescent states as well as spiking states exist in the oscillations, leading to different types of bursting oscillations.

BACKGROUND: Cardiac remodeling is an important mechanism for the occurrence and development of chronic heart failure (CHF). Paeoniflorin (Pae) is the main active ingredient of Chinese herbaceous peony and has novel anti-inflammatory effect. This study was conducted to assess the effects and mechanisms of Pae on cardiac remodeling in CHF rats. METHODS: A cardiac remodeling rat model was induced by isoprenaline (Iso). Pae (20 µg/kg/d) was administrated to CHF rats for six weeks. Cardiac ultrasound was used to assess the structure and function of CHF rats. Collagen volume fraction (CVF) and perivascular collagen volume area of myocardial tissues were calculated. With real-time polymerase chain reaction and Western blot, the protein and mRNA levels of transforming growth factor β1 (TGF-β1) and Smad3 were detected. RESULTS: Compared to Iso group, Pae can alleviate cardiac remodeling and improve cardiac function in CHF rats. The levels of CVF and perivascular collagen volume area reduced in Pae group (P

BACKGROUND: Recent studies have found that adropin is associated with coronary artery disease (CAD). This meta-analysis sought to assess the relationship between serum adropin level and CAD. METHODS: Online databases including the Cochrane Library, PubMed, EMbase, Ovid, CBM, CNKI, VIP and WanFang Data were electronically searched for the clinical study concerning the relationship between serum adropin levels and CAD, including acute myocardial infarction (AMI), unstable angina pectoris (UAP), and stable angina pectoris (SAP). Two reviewers independently screened literature, extracted data and assessed methodological quality of included studies. Standard mean difference (SMD) with its 95% confidence interval (CI) was used as the effect size in this study. Then meta-analysis was performed using RevMan 5.2 software. RESULTS: A total of seven articles involved 945 participants were included. The results indicated that serum adropin level in CAD group was lower than healthy control group (SMD =−2.44, P=0.0008). In the subgroup analysis, the levels of serum adropin in AMI group (SMD =−2.96, P

Cable tunnel fires are mainly caused by single-phase arc grounding faults. The massive energy generated by arc can threaten the safety of the densely laid cable tunnels. In this study, a digital arc fault model with a 220-kV cable transmission system was established on Power Systems Computer Aided Design(PSCAD). The arc model was improved because the parameters were acquired from the experimental results. The arc fault can be divided into two stages: a primary arc at the initiation of the fault and a secondary arc after the tripping of the circuit breakers. The primary arc contains few nonlinear components because of the large arc currents. The secondary arc voltages exhibit nonlinear characteristics because of arc elongation. The secondary arc power continues to increase, however, its amplitude is considerably smaller than the primary arc. The lifetime of the primary arc is dependent on the action of the relaying protection system. Further, some limits based on the energy balance theory were introduced to obtain the extinction time of the secondary arc. In addition, the total energy generated by the arc fault in the 220-kV cable transmission system will eventually become 4891 kJ. This digital arc fault model will significantly contribute to future research with respect to the mechanism of cable tunnel fires.

In recent years, molecular simulation technology, as the third mothed besides experiment and analysis, has been widely used in various fields. In the field of high voltage, molecular simulation is widely used in oilpaper and polymer insulation characteristics analysis, pyrolysis analysis and so on. In this paper, in order to clarify the electric aging mechanism of cross-linked polyethylene(XLPE), a simple XLPE molecular model is established with the ORCA package and the basic sets 3–21G, 6–31G and 6–311G(d, p) are utilized to optimize and get the most stable structure. We have chosen the band length, band gap and charge transfer within the molecule to characterize the XLPE molecule's status under electric field. The results show that the structural parameters and energy of the molecule present linear changes with electric strength. Especially, the band gap presents a downward trend, which means the insulation property of the material has decreased with the electric strength increases. These phenomena reveal the aging mechanism of XLPE molecule under electric field conditions, which is of great significance to the status evaluation of XLPE cable.

This paper introduces a new method to calculate the weight of influence factors on cable failure in 10kV network. A large number of statistical data of cable failure in recent years are investigated to analyze the main causes and influence factors in detail. Different from traditional methods of calculating the weight of factors, the methodology introduced in this paper eliminates subjective judgement by using statistical data. Based on these statistical data, information theory is employed as objectively calculating the weight of influence factors. In this theory, information entropy (IE) reflects the degree of uncertainty. Therefore, using statistical data above, IE of cable status can be obtained. Moreover, under the effect of various external factors, the uncertainty of cable status will get changed. Due to the fact that mutual information entropy (MIE) indicates the variation of IE influenced by outer factors, MIE is used to calculate the weight of influence factors. With the use of algorithm above and detailed information of cable failure, the weight of service years, laying methods and load rate on cable status is obtained. The research results have significant reference values for analyzing influence factors of cable failure and assessment of cable status.

In recent years, in order to improve the efficiency of urban power supply, automatic reclosing operation is gradually applied in the XLPE cable-OHL mixed line. Operation experience shows that the grounding fault occurred in the overhead line, in most cases, is instantaneous and the success rate of reclosing is high. The grounding fault occurred in the cable line is almost permanent and the success of reclosing is quite low. In this paper, a typical mixed line of urban power network was built in PSCAD software. The amplitude-frequency characteristics of overvoltage, caused by single-phase grounding fault of cable segment and overhead line segment, were studied. And the characteristic parameters of two kinds of overvoltage were extracted. According to these parameters, the fault location could be determined and the basis of reclosing strategy was provided.

Supplemental Digital Content is available in the text, Background: Cardiac arrest (CA) is a serious threat to human health. Cardiopulmonary resuscitation (CPR) is an effective treatment for CA. Early and high-quality CPR is closely related to the survival rate of patients with CA. But manual chest compression has a lot of defects. To solve the defects and improve the quality of CPR, mechanical CPR device was invented. However, it has still controversy whether manual chest compression or mechanical chest compression is better. This systematic review was aimed to investigate the difference in clinical outcomes between manual chest compression and Lund University Cardiac Assist System (LUCAS) assisted CPR in patients with out-hospital CA. Methods: Original research studies, conducted on adult out-of-hospital CA, were included. PubMed/Medline, EMBASE, Scopus, Cochrane Library, CNKI, and Wanfang database were searched from the setting to February 21, 2019. Odds ratio (OR) with 95% confidence interval (CI) was selected as effect scale index for evaluation of the difference in return of spontaneous circulation (ROSC), survival to hospital admission, survival to hospital discharge, and survival to 30 days. Random effects model was used in this study to estimate overall mean effects. Results: A total of 6 articles, including 4 randomized controlled trials and 2 nonrandomized controlled trials, were selected. And 8501 subjects were involved to analyze the clinical outcomes of LUCAS and manual chest compression for patients with out-hospital CA. Comparisons of ROSC (33.3% vs 33.0%, P = .98; OR = 1; 95% CI: [0.89,1.13]), survival to hospital admission (22.7% vs 24.3%, P = .32; OR = 0.86; 95% CI: [0.65,1.15]), survival to hospital discharge (8.6% vs 10.7%, P = .50; OR = 0.92; 95% CI: [0.73,1.17]), and survival to 30 days (7.5% vs 8.5%, P = .50; OR = 0.92; 95% CI: [0.73,1.17]) were made. No significant difference was found. Conclusion: The synthesis of available evidence does not support that mechanical chest compression with LUCAS device improves clinical outcome in out-of-hospital CA patients compared with manual chest compression. Large scale studies with improved designs are still needed in the future.

Background: The association between KCNA5 gene variation and systemic sclerosis-associated pulmonary hypertension (SSc-PAH) is unclear. The present meta-analysis was conducted to assess the association between KCNA5 gene variation and SSc-PAH. Methods: Electronic databases were searched for relevant studies on the relationship between KCNA5 gene variation and SSc-PAH. Odds ratio (OR) with 95% confidence interval (CI) was selected as the effect scale indicators using a random-effects model. Statistical analysis was performed using RevMan 5.3 software. Results: A total of 2 articles and 7,583 subjects were included. Among them, 298 were SSc-PAH patients. There was no significant difference found in the comparisons of C/C homozygotes (0.7% vs . 1.7%, OR=0.51, P=0.41), C/T heterozygotes (17.1% vs . 22.7%, OR=0.64, P=0.25) and C/C+C/T heterozygotes (17.8% vs . 24.4%, OR=0.59, P=0.25) between the two groups. Conclusions: The pooled analysis of available data indicates that KCNA5 rs10744676 is not confirmed as an SSc-PAH genetic susceptibility factor.