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The high distribution of water resources among provinces in China considerably impacts the development of society and economy in each region. Thus, it is of great practical significance to examine the water resources carrying capacity (WRCC) of each Chinese province. This paper constructs a comprehensive evaluation index system for the WRCC from two aspects: pressure and support. First, it analyzes dynamic changes in the WRCC of 31 Chinese provinces in China by using the decoupling model (DM). Second, it analyzes the key factors that hinder the improvement of WRCC by using the obstacle degree model (ODM). The study found that there are significant inter-provincial differences in China's WRCC. Provinces with greater natural water resources have a higher WRCC. Under the condition of similar natural water resources, WRCC in economically developed provinces is higher. From 2008 to 2015, China's overall WRCC has been increasing. Moreover, three-fifth of China's provinces can be classified as Upward-type (Upward I, Upward II, and Upward III) provinces and their WRCC is in a good state by considering the decoupling type and trend of WRCC in two periods together. The main obstacle factors hindering the improvement of the WRCC are total water resources ([Formula: see text]), water supply per capita ([Formula: see text]), total water supply ([Formula: see text]), forest cover rate ([Formula: see text]), soil erosion control area ([Formula: see text]), water consumption saving ([Formula: see text]), and water usage penetration rate ([Formula: see text]). This study can provide a scientific basis for understanding change trend of WRCC in Chinese provinces and improve their WRCC.

Online classrooms have become an important way to cope with the uncertainty of changing teaching and learning contexts in universities since the outbreak of the COVID-19 pandemic. However, this learning mode has caused new physical and mental health issues, such as online class-related anxiety. We investigated the association between online class-related anxiety and undergraduates’ academic achievement. The results showed that online class- related anxiety had a negative correlation with undergraduates’ academic achievement. Intrinsic school motivation mediated the relationship between online class-related anxiety and academic achievement, but extrinsic school motivation suppressed the negative link between these variables. Gender played a moderating role in the process of online class-related anxiety affecting academic achievement. This study expands the research perspective of achievement emotion theory, especially in the online learning environment. Emotional intervention strategies can be adjusted according to the gender of college students to promote the improvement of academic achievement.

The aim of the study was to develop a model of coronary microembolization (CME) in rats at a lower cost. We developed a novel rat model without thoracotomy and ventilation under the guidance of echocardiography. Rats were sacrificed at 3 h, 24 h and 1 month postoperatively in both the Echo-CME and Open-chest CME groups for the comparison of the modeling accuracy, mortality, cardiopulmonary circulation, pleural adhesion and ventilation-induced lung injury (VILI). Results showed that the coronary microthrombus formed at 3 h and reached its peak at 24 h postoperatively, which included platelet aggregation and fibrin web. The Echo-group increases success rates, decreased mortality, postoperative complications including pleural adhesion, cardiopulmonary dysfunction and VILI postoperatively than the Open-chest group at 1month postoperatively. The ejection fraction of the CME group decreased to 50% and obvious cardiac fibrosis formed at 3 months postoperatively. Our unique surgical method provided a platform to study molecular mechanisms and potential new pathways for CME treatment.

At present, due to the limitations of drug therapy targets for atherosclerosis, some patients fail to achieve satisfactory efficacy. Cholesterol efflux dysfunction and endothelial cell inflammation are considered to be important factors in the development of atherosclerosis. Peroxisome proliferator-activated receptor gamma (PPAR

Crude oil is the most important energy source in the world, and fluctuations in oil prices can significantly influence investors, companies, and governments. However, crude oil prices have numerous characteristics, including randomness, sudden structural changes, intrinsic nonlinearity, volatility, and chaotic nature. This makes the accurate forecasting of crude oil prices a difficult and challenging task. In this paper, a hybrid prediction model for crude oil futures prices is proposed, the accuracy and robustness of which are demonstrated via controlled experiments and sensitivity analysis. This study uses a new data denoising method for data processing to improve the accuracy and stability of the predictions of crude oil prices. Furthermore, the chaotic time-series prediction method, shallow neural networks, linear model prediction methods, and deep learning methods are adopted as submodels. The results of interval forecasts with narrow widths and high prediction accuracies are derived by introducing a confidence interval adjustment coefficient. The results of the simulation experiments indicate that the proposed hybrid prediction model exhibits higher accuracy and efficiency, as well as better robustness of the forecasting than the control models. In summary, the proposed forecasting framework can derive accurate point and interval forecasts and provide a valuable reference for the price forecasting of crude oil futures.

Circular RNAs (circRNAs) are a kind of closed loop endogenous non-coding RNAs have attracted increasing interest in recent years. However, the mechanism of circRNAs in the pathogenesis of multiple cardiovascular diseases, particularly myocardial ischemia, is rarely reported. In the present study, we examined a circular RNA, hsa_circ_0007623, which is highly expressed in hypoxia-induced human umbilical vein endothelial cells (HUVECs) and can act as a sponge for miR-297, which is involved in cardiac repair after acute myocardial ischemia. In hypoxia-stimulated HUVECs, the inhibition of hsa_circ_0007623 expression was found to reduce cell proliferation, migration, and angiogenesis. Further in vivo experiments confirmed the cardioprotective effect of hsa_circ_0007623 expression in isoproterenol-induced acute ischemia mice. Bioinformatics analysis predicted hsa_circ_0007623, sponge miR-297 and miR-297 directly target VEGFA, which was validated by dual-luciferase assay. Subsequently, functional experiments revealed hsa_circ_0007623 silencing could up-regulate miR-297 and down-regulate VEGFA expression, and reduce cell proliferation, migration, and angiogenesis. We concluded that hsa_circ_0007623 can bind to miR-297, promote cardiac repair after acute myocardial ischemia, and protect cardiac function.

Ferroptosis is associated with the pathology of myocardial ischemia/reperfusion (MI/R) injury following myocardial infarction, which is a leading cause of death worldwide. Although long noncoding RNAs (lncRNAs) are known to regulate gene expression, their roles in MI/R-induced ferroptosis remain unclear. In this study, we explored the lncRNA expression profiles in a rat model of MI/R injury and found that the novel lncRNA, lncAABR07025387.1, was highly expressed in MI/R-injured myocardial tissues and hypoxia/reoxygenation (H/R)-challenged myocardial cells. Silencing lncAABR07025387.1 improved MI/R injury

The conventional model predictive control (MPC) of permanent magnet synchronous motor (PMSM) always has a complicated computational burden and large current or torque ripples, which result in deteriorated control performance and difficult to achieve practical operating conditions. To address those issues, this digest proposes an improved model predictive flux-linkage control (MPFC) strategy for PMSM without weight coefficients. The proposed scheme retains excellent control performance of MPC with simple calculation. Firstly, according to the mathematical model of PMSM, the prediction model of flux- linkage established. The relationship between flux linkage and selected voltage vector is analyzed and a new sector division solution is discussed. Then, the design and implementation of the improved MPFC scheme is presented. Finally, a comprehensive simulation test has been conducted to verify the effectiveness of the proposed scheme.

The negative input impedance with the constant power load causes dc-link voltage and current oscillations in the metro traction drive system (MTDS) and weakens the stability of the system. In this digest, a small signal model of the simplified equivalent circuit of the MTDS is established, and the oscillation mechanism is analyzed. This digest proposes an active damping method based on the virtual damping and pseudolinear enhanced phase-locked loop (PL-EPLL). The stabilization scheme is realized by three parts: 1) the estimation of the dc-link voltage variation; 2) the generation of damping power; and 3) generation of stator current command. The dc-link voltage variation is firstly estimated by the PL-EPLL. And damping power is achieved by virtual damping resister in series with line inductor. Based on the inverter power control, q-axis current is obtained. Simulation results show that the active damping method effectively suppresses dc–link oscillation and improves the stability of MTDS.

Background The inflammatory state of diabetes promotes high platelet response and endothelial adhesion, which are the main risk factors for cardiovascular events. Tetramethylpyrazine (TMP) is an amide alkaloid isolated from the traditional Chinese medicine Rhizoma Ligustici Chuanxiong, which has been widely used in the clinical treatment of ischemic cardiovascular disease. Purpose This study aimed to investigate whether TMP could alleviate diabetes-induced high platelet response and endothelial adhesion and the underlying mechanisms. Methods Type 2 diabetes mellitus (T2DM) rat model was established by high-fat feeding combined with low dose of streptozotocin. Rats in the TMP treatment group were administered with TMP (100 or 200 mg/kg) for 21 days. Cultured human umbilical vein endothelial cells (HUVECs) were stimulated with glucose (5.5 mM) to induce endothelial activation. The NOD-like receptor protein 3 (NLRP3) over- and low-expressing cell models were established via transfection of NLRP3 lentivirus plasmid into HUVECs. INF39 (25 mg/kg), a chemical inhibitor of NLRP3 inflammasome, was used to explore the role of NLRP3 in T2DM associated high platelet response and endothelial adhesion. Results TMP effectively improved the prothrombotic phenotypes and inhibited the expression of vascular inflammatory factors and adhesion molecules in T2DM rats. TMP inhibited NLRP3 inflammasome and reduced the adhesion of HUVECs to platelets and monocytes in vitro. Over-expression of NLRP3 blocked the effect of TMP on HUVECs activation and adhesion, while TMP had no effect on NLRP3 low-expressing HUVECs. The NLRP3 inhibitor INF39 produced similar effects of TMP on diabetes-induced high platelet response, endothelial adhesion and vascular inflammation. Conclusion TMP ameliorates diabetes-induced high platelet response and endothelial adhesion via inhibiting NLRP3 inflammasome activation in T2DM rats, which provide a new basis for the clinical prevention and treatment of diabetes-associated cardiovascular events.

Background Atherosclerosis plaque is a major cause of cardiovascular diseases across the globe, which is characterized by a gradual formation of atherosclerotic plaque, hardening, and narrowing of the arteries. Nano-materials can serve as powerful delivery platforms for atherosclerosis treatment. Herein we systematically developed polymeric capsule with active targeting property encapsulating curcumin (Cur) and C-C chemokine receptor type 2 with short-interfering RNA (CCR2-siRNA) for combined treatment, which was also loaded with Gd3+ for magnatic resonance imaging (MRI) and a near-infrared fluorochrome (IR780) for fluorescence imaging (FI).Results The resulting nano-capsule exhibited a favorable hydrodynamic size and negative surface charge. More importantly, the negative charge and active-targeting peptide resulted in enhanced accumulation of nano-capsule in the established atherosclerotic plaques, thereby achieving targeted drug release. The in vitro and in vivo results indicated the effective diagnostic and therapeutic sensitivity, which could promote the development of theranostics for clinical implementation.Conclusions This study demonstrated that chemotherapy combined with gene therapy can displayed synergistic effect in atherosclerosis treatment, which possessed efficient management of atherosclerosis.

Chongli Xu,1,2 Caihong Liang,2 Weixin Sun,3 Jiandong Chen,3 Xiaohu Chen3 1Nanjing University of Chinese Medicine, Nanjing 210029, People’s Republic of China; 2Jiangnin Hospital of Nanjing, Nanjing 211100, People’s Republic of China; 3Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, People’s Republic of China Background: Glycyrrhizic acid (GA), a bioactive triterpenoid saponin isolated from the roots of licorice plants (Glycyrrhiza glabra), has been shown to exert a variety of pharmacological activities and is considered to have potential therapeutic applications. The purpose of the present study was to investigate the cardioprotective effect of GA on myocardial ischemia (MI) injury rats induced by isoproterenol (ISO), and explore the potential mechanisms underlying these effects. Materials and methods: The rats were randomized into five groups: control, ISO, ISO+diltiazem (10 mg/kg), ISO+GA (10 mg/kg), and ISO+GA (20 mg/kg). Electrocardiogram and histopathological examination were performed. Markers of cardiac marker enzymes (creatine kinase-MB, lactate dehydrogenase), oxidative stress (superoxide dismutase, malondialdehyde [MDA]), and inflammation (TNF-α, IL-1β, and IL-6) were also measured in each group. Proteins involved in NF-κB and Nrf-2/HO-1 pathway were detected by Western blot. Results: GA decreased the ST elevation induced by MI, decreased serum levels of creatine kinase, lactate dehydrogenase, malondialdehyde, IL-6, IL-1β, and TNF-α, and increased serum superoxide dismutase and malondialdehyde activities. Furthermore, GA increased the protein levels of Nrf-2 and HO-1 and downregulated the phosphorylation of IκB, and NF-κB p65 in ISO-induced MI. Conclusion: These observations indicated that GA has cardioprotective effects against MI, and these effects might be related to the activation of Nrf-2/HO-1 and inhibition of NF-κB signaling pathway in the myocardium. Keywords: glycyrrhizic acid, myocardial ischemia, Nrf-2/HO-1, oxidative stress, inflammation

Waste management is a major source of global greenhouse gas (GHG) emissions and many opportunities exist to reduce these emissions. To identify the GHG emissions from waste management in China, the characteristics of MSW and the current and future treatment management strategies, five typical management scenarios were modeled by EaseTech software following the principles of life cycle inventory and analyzed based on the carbon and energy flows. Due to the high organic fraction (50–70%) and moisture content (>50%) of Chinese municipal solid waste (MSW), the net GHG emissions in waste management had a significant difference from the developed countries. It was found that the poor landfill gas (LFG) collection efficiency and low carbon storage resulted landfilling with flaring and landfilling with biogas recovery scenarios were the largest GHG emissions (192 and 117 kgCO2-Eq/t, respectively). In contrast, incineration had the best energy recovery rate (19%), and, by grid emissions substitution, led to a substantial decrease in net GHG emissions (−124 kgCO2-Eq/t). Due to the high energy consumption in operation, the unavoidable leakage of CH4 and N2O in treatment, and the further release of CH4 in disposing of the digested residue or composted product, the scenarios with biological treatment of the organic fractions after sorting, such as composting or anaerobic digestion (AD), did not lead to the outstanding GHG reductions (emissions of 32 and −36 kgCO2-Eq/t, respectively) as expected.

This paper constructs a model of inverter-induction motor (IM) vector control system based on linear time-periodic (LTP) theory. The basic contents of the LTP theory are firstly presented for illustrating basic modeling ideas. Compared to the traditional linear time-invariant (LTI) model, the LTP model considers the coupling effect between input and output signals. Afterward, the small signal model of the inverter-motor system is constructed, where the coordinate transformation and the effect of SVPWM have been taken into account. Moreover, the accuracy of the model has been verified according to signal reproducing and BODE diagram. Simulation results have confirmed the accuracy of LTP modeling of inverter-induction motor (IM) system and theoretical analysis of DC-link stability.

Aims and methods Acute myocardial infarction (AMI) is a common cardiovascular disease with high mortality. Astragaloside IV (AS-IV) was reported to have cardioprotective effect after AMI. We hypothesize that the cardioprotective role of AS-IV is exerted by enhancing angiogenesis via regulating PTEN/PI3K/Akt signaling pathway. To valid our hypothesis, AMI rats and human umbilical vein endothelial cells (HUVECs) were employed in our study. Key findings After treatment, cardiac function, survival rate, infarct size, pathological changes and fibrosis, cell apoptosis, ultrastructural changes, angiogenesis and expression of PTEN/PI3K/Akt signaling pathway were evaluated, respectively. In vitro study we detected proliferation, tube formation and signaling pathway activation of HUVECs treated with AS-IV, lentivirus overexpressed PTEN was employed to elucidate the potential mechanism. The results indicated that AS-IV administration significantly improved cardiac function and survival rate, limited infarct size, ameliorated pathological changes and fibrosis deposition, inhibited apoptosis, relieved ultrastructure injury and enhanced angiogenesis, PTEN/PI3K/Akt signaling pathway was activated simultaneously compared to the model group. In vitro study suggested that AS-IV treatment promoted cell proliferation and tube formation, and induced PTEN/PI3K/Akt signaling pathway activation. Importantly, overexpression of PTEN by lentivirus abolished AS-IV-induced angiogenesis. Significance Our study indicated that AS-IV could promote angiogenesis and cardioprotection after myocardial infarction. The mechanisms involve activation of PTEN/PI3K/Akt signaling pathway.

Shaking table model tests were carried out to study the seismic behaviors of double box utility tunnel with joint connections and the surrounding soil. The seismic wave obtained from 1952 Taft earthquake was employed as the input in this study, and its PGA has been adjusted to 0.2 g, 0.4 g, 0.8 g, and 1.2 g, respectively. In addition, a series of sine waves with PGA of 0.2 g and frequencies of 5 Hz, 10 Hz, 15 Hz, 20 Hz, 25 Hz, and 30 Hz were applied to study the effect of frequency characteristics on seismic behavior of the utility tunnel and the surrounding soil. The testing results show that the laminar soil container does not impose significant boundary effect, and the dynamic earth pressure response is significantly influenced due to existence of the joint connection. Besides, the effect of soil-structure interaction on seismic behaviors is becoming even more obvious as the input PGA increases. The acceleration response is also significantly influenced by the dynamic property of the soil. Greater bending moment occurs at the corners of the structure, and its increasing ratio will decrease with an increasing input PGA magnitude. Lastly, the effect of frequency is significant. Therefore, it is noteworthy that the possible effect of natural frequency is considered when the utility tunnel is under construction.

Clogging of the leachate collection system (LCS) has been a common operation problem in municipal solid waste (MSW) landfills in China, which can result in high water levels that threaten the safety of landfill operations. To determine the cause of failure in an LCS, raw leachate from a municipal solid waste transfer station was collected and the high content of particulate matter was characterized. Based on the parameters obtained in a filtration test, a numerical simulation was performed to estimate the influence of particle deposition on drainage system clogging. The results showed that LCSs were confronted with the risk of clogging due to the deposition of particulate matter resulting from the higher concentration of total suspended solids (TSS level > 2200 mg L−1) and larger particle size (>30% TSS particles > 15 μm) in the leachate. On one hand, the non-woven geotextile, as the upper layer of the LCS, retained most particulate matter of large diameters, reducing its hydraulic conductivity to approximately 10−8 to 10−9 m s−1 after 1–2 years of operation and perching significant leachate above it (0.6–0.7 m). On the other hand, the geotextile prevented the gravel layer from physically clogging and minimized the leachate head above the bottom liner. Therefore, the role of geotextile should be balanced to optimize the LCS in MSW landfills in China.

High on-aspirin platelet reactivity (HAPR) has been associated with compromised aspirin efficacy in patients with diabetes suffering from acute cardiovascular events, but the key mechanisms remain elusive. The objective of this study was to uncover the potential link between pathogenic accumulation of salicylic acid (SA), the major metabolite of aspirin, and HAPR in diabetic state. Aspirin failed to inhibit platelet CD62P expression and thromboxane (TX) B2/6-keto-prostaglandin（PG）F1α ratio in a type 2 diabetes mellitus (T2DM) mice model, particularly in the female, which were unanimously accompanied by significantly higher plasma SA concentrations. Pre-administration with SA increased both platelet CD62P expression and TXB2/6-keto-PGF1α ratio in female T2DM mice, while pretreatment with NaHCO3 caused the opposite effect. On the in vitro human umbilical vein endothelial cells (HUVECs)-platelet interaction assay, SA suppressed inflammation-induced cyclooxygenase-2 upregulation on HUVECs and attenuated their inhibitory effect on platelet aggregation in a dose-dependent manner. The prolonged retention of SA in diabetes may be partially explained by the downregulation of various SA efflux transporters in the kidney and the decreased urine pH. Importantly, in female aspirin non-responsive patients, the trough plasma concentration of SA are markedly increased with T2DM treated with long-term aspirin, and TXB2/6-keto-PGF1α ratio and uric acid level in plasma are positively correlated with SA concentration. Our findings support that the accumulation of SA represents an important factor in causing HAPR in diabetes, and that targeting impaired SA excretion may become a novel intervention strategy to diabetes-associated HAPR.

To solve the network performance deterioration caused by network nodes failure according to unexpected and unforeseen environmental changes in wireless sensor network WSN, a high fault-tolerant and energy-efficient multipath routing protocol based on the idea of hybrid, energy-efficient distributed HEED clustering protocol, called HEED fault tolerant HEED-FT is proposed in this paper. To improve the routing reliability and energy balance between cluster heads, the HEED-FT algorithm first introduces the non-probability waiting time, residue energy and centres to improve the cluster lifetime. Then multiple clustering parameters are applied with different hierarchy which can control the ideal topology distribution of the cluster heads. Finally, a multiple trees Gabriel graph MTGG model is put forward to get a reliable communication link with multiple clustering parameters which can ensure the nodes in an ideal cluster topology distribution. The simulation results show that HEED-FT has less energy consumption, higher reliability and longer network survival than the traditional algorithms.