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Pulmonary vascular remodeling is the critical structural alteration and pathological feature in pulmonary hypertension (PH) and involves changes in the intima, media and adventitia. Pulmonary vascular remodeling consists of the proliferation and phenotypic transformation of pulmonary artery endothelial cells (PAECs) and pulmonary artery smooth muscle cells (PASMCs) of the middle membranous pulmonary artery, as well as complex interactions involving external layer pulmonary artery fibroblasts (PAFs) and extracellular matrix (ECM). Inflammatory mechanisms, apoptosis and other factors in the vascular wall are influenced by different mechanisms that likely act in concert to drive disease progression. This article reviews these pathological changes and highlights some pathogenetic mechanisms involved in the remodeling process. [ABSTRACT FROM AUTHOR]

Pulmonary hypertension (PH) is a chronic and progressive disease caused by obstructions and functional changes of small pulmonary arteries. Current treatment options of PH are costly with patients needing long-term taking medicine. The traditional Chinese medicine (TCM) compound "Shufeiya Recipe" was used to intervene in monocrotaline- (MCT-) induced pulmonary hypertension in rats. The rats were randomly divided into the control group, model group, positive drug (Sildenafil) group, and Shufeiya Recipe low-, moderate-, and high-dose groups. The improvement effect of the Shufeiya Recipe on the mean pulmonary artery pressure (mPAP) was assessed in PH rats, and pathological staining was used to observe the pathological changes of lung tissue. The impact of the Shufeiya Recipe on oxidative stress damage in rats with pulmonary hypertension and the regulation of SIRT3/FOXO3a and its downstream signaling pathways were determined. The results showed that Shufeiya Recipe could significantly downregulate mPAP and improve lung histopathological changes; downregulate serum levels of reactive oxygen species (ROS); upregulate the concentrations of COX-1 and COX-2 and the activity of Mn-SOD; inhibit oxidative response damage; promote the protein expression of SIRT3, FOXO3a, p-PI3K, p-AKT, and p-eNOS; increase the level of expression of NO, sGC, cGMP, and PKG; and downregulate the level of protein expression of Ras, p-MEK1/2, p-ERK1/2 and c-fos. These results indicate that Shufeiya Recipe can improve MCT-induced pulmonary hypertension in rats by regulating SIRT3/FOXO3a and its downstream PI3K/AKT/eNOS and Ras/ERK signaling pathways. [ABSTRACT FROM AUTHOR]

• As the preload force increases, the safety vent opens earlier. • The battery expansion behavior has a mitigating effect on the gas pressure. • By constructing a TR hazard assessment model, the TR hazard is smallest at 3 kN. In electrochemical energy storage systems, large-format LiFePO 4 (LFP) batteries are usually formed the battery pack under preload force. However, the preload force effect on the safety of the batteries remains unclear. In this study, the TR and gas venting of the 280 Ah LFP batteries at 100% state of charge under four preload forces (0, 3, 6, and 9 kN) are investigated experimentally. The novelty compared to previous studies is that the fixture with a pressure sensor is used to set different preload forces before the experiment and monitor the expansion behavior of the LFP batteries during TR. The results quantitatively analyse the relationship between preload force and TR hazard of prismatic LFP battery. Two important results are presented: (I) the gas release inside LFP battery is horizontal and vertical at the same time, and the battery expansion behavior has a mitigating effect on gas pressure. (II) the TR hazard assessment model is pioneered to assess the TR hazard of batteries under four preload forces. The results show that the TR hazard is minimal at 3 kN. These results provide an effective guide to the setting of preload force and the emergency response to TR. [ABSTRACT FROM AUTHOR]

As lithium-ion batteries (LIBs) are becoming more widely applied in aviation, growing attention has been paid to thermal runaway (TR) propagation due to its high complexity in unique low-pressure environments. This paper investigates the characteristics of TR propagation for the LiFePO 4 and LiNi 0.5 Co 0.2 Mn 0.3 O 2 modules at 95, 70, and 35 kPa. Some critical parameters in LIB modules, such as TR behavior, temperature, and propagation speed are analyzed. The results indicate that TR behaviors become weaker and the average maximum temperature of modules decreases 20–50 °C as the pressure decreases. The TR time of the LiFePO 4 module decreases from 1218 to 603 s, when the pressure decreases from 95 to 35 kPa, but the LiNi 0.5 Co 0.2 Mn 0.3 O 2 module increases from 33 to 151 s, indicating a reduction in the TR propagation time of 50.1% for the LiFePO 4 module but an increase of 357.6% for the LiNi 0.5 Co 0.2 Mn 0.3 O 2 module. As the pressure decreases, the mass losses of modules decrease, but the impact force of the LiNi 0.5 Co 0.2 Mn 0.3 O 2 battery safety venting increases. Finally, a heat transfer model is established to explain the trend in TR influence at low pressure. This work clarifies the TR propagation characteristics of LIBs with two cathodes, which can help improve the safe use of LIB modules at low pressure. • Pioneering study on thermal runaway propagation at low pressure. • The safety venting of LFP and NCM batteries is further studied at low pressure. • Thermal runaway propagation features at low pressures are verified by theory. [ABSTRACT FROM AUTHOR]

[Display omitted] With increasingly more electrochemical energy storage systems installed, the safety issues of lithium batteries, such as fire explosions, have aroused greater concerns. In this study, the thermal runaway behaviors of two different structures of lithium–iron-phosphate battery packs were compared. A fire explosion occurred in battery pack I, which had a small venting area and void volume, but battery pack II with a large venting area and the void volume kept safe. To explain these phenomena, a new experimental method coupling multiple measurements was proposed in this study to survey the velocity, composition, and temperature of venting gas. The venting gas velocity had two peaks, with its maximum value reaching about 270 m/s. Besides, the venting gas was mainly composed of hydrogen and carbon dioxide, accounting for around 30.33% and 38.86%, respectively. With the experimental data used as boundary conditions in a mathematical model, the diffusion behaviors of the venting gas within these two battery packs were derived. By comparing the flammable gas concentration with their lower explosion limits and upper limits, this study found that the high concentration of hydrogen and ethylene might bear the main responsibility for the fire explosion in battery pack I. [ABSTRACT FROM AUTHOR]

Amongst the background of the popularization of the lithium-ion battery (LIB), the thermal issues have attracted a significant amount of attention. In the present paper, a novel integrated system is proposed with thermal management and rapid cooling based on C 6 F 12 O spray cooling in a closed loop. Through experiments using a 4 × 4 dummy 18650 cylindrical battery pack, the cooling performance of the battery thermal management system (BTMS) based on the C 6 F 12 O spray cooling is demonstrated to be effective. Further, the controllable heat generation benefits for the analysis of heat dissipation mechanisms. For the condition of 6 cm spray height with 2.05 g/s flow rate, the heat is taken away by the liquid film accounted for around 30% of the total heat dissipation, while that of direct spray cooling accounted for around 70%. In the rapid cooling experiment, compared with the blank experiment, the thermal runaway maximum temperature significantly decreased by 517.1 °C and the thermal runaway of the first battery is delayed by 229 s. Owing to the significantly effective heat removal ability of C 6 F 12 O spray cooling, the propagation of the thermal runaway is cut off. • A novel integrated system with thermal management and rapid cooling is proposed. • The effects of spray height, flow rate, and heat generation are explored. • The effectiveness of the proposed management system is proved experimentally. • The propagation of thermal runaway is cut off with the application of spray cooling. [ABSTRACT FROM AUTHOR]

Background: Optimized New Shengmai Powder (ONSMP) is a traditional Chinese medicine formula with significant anti-heart failure and myocardial fibrosis effects, but the specific molecular biological mechanisms are not fully understood. Methods: In this study, we first used network pharmacology to analyze the ONSMP's active ingredients, core signaling pathways, and core targets. Second, calculate the affinity and binding modes of the ONSMP components to the core targets using molecular docking. Finally, the heart failure rat model was established by ligating the left anterior descending branch of the coronary artery and assessing the effect of ONSMP on myocardial fibrosis in heart failure using echocardiography, cardiac organ coefficients, heart failure markers, and pathological sections after 4 weeks of drug intervention. The cAMP level in rat myocardium was determined using Elisa, the α-SMA and FSP-1 positive expression determined by immunohistochemistry, and the protein and mRNA levels of the cAMP/Rap1A signaling pathway were detected by Western Blotting and quantitative real-time PCR, respectively. Results: The result shows that the possible mechanism of ONSMP in reducing myocardial fibrosis also includes the use of 12 active ingredients such as baicalin, vitamin D, resveratrol, tanshinone IIA, emodin, 15,16-dihydrotanshinone-i to regulate β1-AR, AC6, EPAC1, Rap1 A, STAT3, and CCND1 on the cAMP/Rap1A signaling pathway, thereby inhibiting the proliferation of cardiac fibroblasts and reduce the excessive secretion of collagen, effectively improve cardiac function and ventricular remodeling in heart failure rats. Conclusion: This research shows that ONSMP can inhibit myocardial fibrosis and delay heart failure through the cAMP/Rap1A signaling pathway. [ABSTRACT FROM AUTHOR]

Nowadays, an effective and clean extinguishing agent or technology is highly desirable for lithium-ion battery (LIB) fires. Herein, the physicochemical properties and extinguishing effects of various extinguishing agents on 243 Ah lithium iron phosphate (LFP) battery fires are investigated systematically. The extinguishing mechanisms are deeply analyzed and the performance is comprehensively evaluated from the aspects of thermal runaway (TR) and toxicity suppression, cooling and extinguishing efficiency. Compared with HFC-227ea, C 6 F 12 O can absorb more heat through vaporization, thereby improving extinguishing and cooling efficiency. The lack of chemical inhibition effect and the tiny droplet size make water mist unable to suppress the high-temperature jet fire, but it has the lowest toxicity and highest cooling efficiency of 54.6%. F-500 and FireIce can improve the extinguishing performance of the water mist by encapsulating and taking hydrocarbon fuel away from the fire zone and inhibiting free radicals in the flame, respectively. 3% F-500 has the extinguishing efficiency of 78.4% and TR efficiency of 64.1%, while maintaining the cooling performance well. In the future, a novel type of fire-extinguishing agent with high heat capacity and latent heat, excellent extinguishing performance, high wettability, low toxicity and insulating properties is expected to be developed for LIB fires. [Display omitted] [ABSTRACT FROM AUTHOR]

As an advanced energy storage medium, lithium-ion batteries (LIBs) are being used in aircraft and other aviation fields owing their unique advantages. The thermal runaway (TR) behaviours of LIBs used in aircraft are more complicated and dangerous due to the special operating environments, such as low pressure and enclosed environments. Therefore, a special test platform was designed to study the effect of low pressure on the TR characteristics of 2.2 Ah 18,650 type LIBs in this work. Some critical parameters of TR were obtained, such as onset temperature of TR, maximum temperature, voltage drop time, pressure, and the explosion limit of gases, etc. The results show that with the pressure increasing, the TR onset temperature, maximum temperature, and pressure increase in the test chamber, and the voltage drop time postpones. In addition, the amount of released gas and the explosion limitation range of gases increase with the decrease of the initial pressure. This means it's easier to occur but with weaker hazard of TR at lower pressure. Besides, the SEM results reveal that deformation and structural damage of cathode materials, which is attributed to the increase of the large amount of gas released at the electrode material level. These results provide the basis for the safe application and storage of LIBs in a confined space under different pressures. [ABSTRACT FROM AUTHOR]

Lithium ion batteries (LIBs) have become the dominate power sources for various electronic devices. However, thermal runaway (TR) and fire behaviors in LIBs are significant issues during usage, and the fire risks are increasing owing to the widespread application of large-scale LIBs. In order to investigate the TR and its consequences, two kinds of TR tests were conducted triggered by overheating and overcharging ways. The cells are 228 Ah with LiFePO4 as cathode. The TR and fire behaviors were studied comprehensively from the aspect of experimental photographs, temperature characteristics, heat release rate (HRR), total heat release (THR), voltage and mass loss variation. The effects of different triggers were investigated. Under the two trigger conditions, the LIBs did not self-ignite and instead only release a large amount of gases or aerosols. With external ignition sources, the combustion process can be classified into four stages. The relationship between TR and fire behaviors related to the two conditions are discussed, respectively. Compared with overheating, the batteries burn more violently and have higher fire risks during overcharging tests. The work is supposed to provide valuable fundamental data and theory guidance for early warning technology and fire protection. [ABSTRACT FROM AUTHOR]

Purpose: Total hip arthroplasty (THA) in patients with rheumatoid arthritis (RA) has been associated with an increased risk of periprosthetic joint infection, periprosthetic fractures, dislocations, and post-operative blood transfusion. However, higher post-operative blood transfusion is unclear whether it reflects peri-operative blood loss or is characteristic of RA. This study aimed to compare the complications, allogenic blood transfusion, albumin use, and peri-operative blood loss between patients who underwent THA because of RA or osteoarthritis (OA). Methods: Patients undergoing cementless THA for hip RA (n = 220) or hip OA (n = 261) at our hospital between 2011 and 2021 were retrospectively enrolled. Deep vein thrombosis, pulmonary embolism, myocardial infarction, calf muscular venous thrombosis, wound complications, deep prosthetic infection, hip prosthesis dislocation, periprosthetic fractures, 30-day mortality, 90-day readmission, allogeneic blood transfusion, and albumin infusions were considered as primary outcomes, while secondary outcomes included the number of perioperative anaemia patients as well as total, intra-operative, and hidden blood loss. Results: Compared to the OA group, patients with hip RA showed significantly higher rates of wound aseptic complications, hip prosthesis dislocation, homologous transfusion, and albumin use. RA patients also showed a significantly higher prevalence of pre-operative anemia. However, no significant differences were observed between the two groups in total, intra-operative, or hidden blood loss. Conclusions: Our study suggests that RA patients undergoing THA are at a higher risk of wound aseptic complications and hip prosthesis dislocation than patients with hip OA. Pre-operative anaemia and hypoalbuminaemia in patients with hip RA place them at a significantly higher risk of post-operative blood transfusion and use of albumin. [ABSTRACT FROM AUTHOR]

Thermal runaway propagation (TRP) of lithium iron phosphate batteries (LFP) has become a key technical problem due to its risk of causing large-scale fire accidents. This work systematically investigates the TRP behavior of 280 Ah LFP batteries with different SOCs through experiments. Three different SOCs including 40 %, 80 %, and 100 % are chosen. In addition to key TRP characteristic parameters such as temperature, TRP time and speed are analyzed, more importantly, the energy flow distribution during the TRP of large-size LFP module is also revealed. The results indicate that among the three groups of modules, TRP occurs only in the module with 100 % SOC, which is attributed to the higher internal energy (666.11 kJ) and heat transfer power (264.07 W). For the module with 100 % SOC, the TRP time interval fluctuates from 667 s to 1305 s, and the TRP speed is in the range of 0.05–0.12 mm/s. Furthermore, the energy flow distribution indicates that more than 75 % of the energy is used to heat battery itself, and approximately 20 % is carried out by ejecta. Less than 10 % can trigger neighboring batteries into thermal runaway. This work may provide important guidance for the process safety design of energy storage power stations. [ABSTRACT FROM AUTHOR]

Objective. This study is aimed at exploring the molecular mechanism of Shufeiya recipe in the treatment of pulmonary hypertension (PH) using network pharmacology and molecular docking analysis. Methods. Active components and their target proteins in the recipe were screened using the TCMSP database. PH-related core proteins were screened using GeneCards, STRING database, and Cytoscape-v3.8.2. Common proteins were obtained by intersection of the target proteins of these recipe active components and pH-related core proteins. Rx64 4.0.2 software was used to perform GO functional enrichment analysis and KEGG pathway enrichment analysis on the common proteins to obtain pathway-enriched proteins, and then core enriched proteins were further screened. We analyzed the relationship between the active components and pathway-enriched proteins using Cytoscape-v3.8.2. AutoDock Vina was used to dock their core proteins into the components. Results. Shufeiya recipe contained 67 active components. 61 common proteins of the target proteins of the active components and PH-related core proteins were obtained. The treatment involved both functional and pathway regulations. The core pathway-enriched proteins were prostaglandin G/H synthase 2 (PTGS2), epidermal growth factor receptor (EGFR), and RAC-alpha serine/threonine-protein kinase (AKT1), and their binding energies to the corresponding components were all less than -5 kJ•mol-1. Conclusion. It was found that the main mechanism might be the active components acting on the core pathway-enriched proteins to regulate related signaling pathways, thereby playing roles in anticoagulation, vasodilation, anti-PASMC proliferation, promotion of PAECs apoptosis, inhibition of oxidative stress, and anti-inflammatory effects. [ABSTRACT FROM AUTHOR]

Optimized New Shengmai Powder (ONSMP) is a traditional Chinese medicine (TCM) formula for heart failure treatment. MAPK signaling pathway is the key driver of myocardial fibrosis in heart failure. However, the mechanism of ONSMP on myocardial fibrosis and MAPK signaling pathway remains unclear. To evaluate the effect of ONSMP against myocardial fibrosis in heart failure and the underlying mechanisms. Firstly, UHPLC-Q-Exactive-MS/MS was used to identify the active components in ONSMP. Secondly, a rat model of heart failure was established by ligating the left anterior descending branch of the coronary artery. After four weeks of intragastric administration of ONSMP, we used various classic tests, including echocardiography, exhaustive swimming, cardiopulmonary coefficient, heart failure markers, and cardiac pathological section, to assess the prescription's anti-myocardial fibrosis in heart failure properties. AGEs, Ang Ⅱ, VEGF, CTGF, and TGFβ levels in rat serum were quantified using ELISA. The positive expression of p-ERK1/2 and p-JNK1/2 of rat myocardium was determined immunohistochemical. The protein and mRNA levels of genes involved in the MAPK signaling pathway and myocardial fibrosis were measured using western blotting or real-time PCR. The main components of ONSMP that regulate the MAPK signaling pathway are isorhamnetin, kaempferol, quercetin, and tanshinone ⅡA. ONSMP ameliorated cardiac function and exercise tolerance and reduced cardiopulmonary coefficient, heart failure marker levels, and myocardial fibrosis in the heart failure rats. In addition, ONSMP diminished the serum MAPK pathway activator levels, positive expression level of p-ERK1/2 and p-JNK1/2, protein and mRNA levels of components of the MAPK signaling pathway in the myocardial tissue of heart failure rat, indicating that it inhibits MAPK signaling pathway. ONSMP delayed heart failure by inhibiting myocardial fibrosis via the MAPK signaling pathway. [Display omitted] [ABSTRACT FROM AUTHOR]

Nucleate pool boiling heat transfer experiments have been conducted to nanofluids on a horizontal cylinder tube under atmospheric pressure. The nanofluids are prepared by dispersing Al2O3 nanoparticles into distilled water at concentrations of 0.001, 0.01, 0.1, 1 and 2 wt.% with or without sodium, 4-dodecylbenzenesulfonate (SDBS). The experimental results showed that: nanofluids at lower concentrations (0.001 wt.% to 1 wt.%) can obviously enhance the pool boiling heat transfer performance, but signs of deterioration can be observed at higher concentration (2 wt.%). The presence of SDBS can obviously enhance the pool boiling heat transfer performance, and with the presence of SDBS, a maximum enhancement ratio of BHTC of 69.88%, and a maximum decrease ratio of super heat of 41.12% can be found in Group NS5 and NS4, respectively. The tube diameter and wall thickness of heating surface are the influential factors for boiling heat transfer coefficient. Besides, we find that Rohsenow formula failed to predict the characteristics of nanofluids. The mechanism study shows that: the decrease of surface tension, which leads to the decrease of bubble departure diameter, and the presence of agglomerates in nanofluids are the reasons for the enhanced pool boiling heat transfer performance. At higher concentration, particle deposition will lead to the decrease of distribution density of the vaporization core, and as a result of that, the boiling heat transfer performance will deteriorate. Nucleate pool boiling heat transfer experiments were conducted with Al2O3/water nanofluids which were prepared by two-step method. The nanoparticle concentration and the presence of sodium, 4-dodecylbenzenesulfonate (SDBS), as well as the tube diameter and wall thickness of main heater were found to be the influential factors on the heat transfer performance. The investigation on the bubbles generated on heating surface, the agglomerates and the boiling surface also confirmed the heat transfer mechanism which was found in the experiments. [ABSTRACT FROM AUTHOR]

The dynamic illustration and outline of LiFePO4 battery thermal runaway mechanism. [Display omitted] • Differential analysis of DSC and ARC tests is aimed to explore the reaction sequence. • A detailed LiFePO 4 battery thermal runaway mechanism is clarified. • Kinetics analysis is well applied to cell-level thermal runaway prediction. The complex chemical composition and material interactions of lithium-ion batteries challenge the in-depth understanding of thermal runaway reactions and failure mechanisms. In this study, detailed analysis and implementation have been made from three levels to further explain the thermal failure mechanism, from material interactions to cell-level experiments and applications. The LiFePO 4 thermal runaway mechanism is put forward to characterize exothermic peaks from differential analysis of differential scanning calorimetry (DSC) and Accelerating Rate Calorimetry (ARC) data. Furthermore, the development, parameterization, and application of the thermal runaway prediction model are also discussed. Multi-heating rate data is a prerequisite to kinetic analysis and modeling work and provides valuable data set for LiFePO 4 thermal failure. And the unraveled mechanism is believed to provide a profound understanding of the thermal failure mechanism, strengthening interactions between material characterization and thermal runaway modeling. [ABSTRACT FROM AUTHOR]

Biomass is widely used in residential and industrial sectors as a renewable and carbon-neutral energy source, however, NO x emissions caused by the heat treatment of biomass are of concern. The nitrogen element in biomass plays an important role in N-containing products generated from pyrolysis, while the migration behaviors of fuel-N are still unknown. Slow pyrolysis experiments of maple wood and maize straw were conducted at 350–650 °C in this study. The TG, XPS and GC/MS technologies were performed to investigate the nitrogen migration pathways during prolysis. Results demonstrated that the fuel-N in the two species mainly exists as protein-N, amide-N and inorganic-N functional groups. Char-N occupied the most of total fuel-N from 350 °C to 450 °C, while the yields of tar-N and NO x precursors-N (NH 3 -N and HCN-N) increased gradually with the rising temperatures. NH 3 was found to be the main NO x precursor for the both species, accounting for 15.01–20.19 wt% and 3.18–5.91 wt% of fuel-N in maple wood and maize straw, respectively. More than 85% of NH 3 -N was produced between 350 °C and 450 °C, attributing to the conversion of fuel-N and tar-N in the devolatilization stage. Differently, around 50% of HCN-N yields were produced by the secondary decomposition of tar-N and char-N at higher temperatures (≥550 °C). Particularly, char-N showed a greater thermal stability in maize straw, while a much higher conversion ratio of NO x precursors-N was observed from maple wood pyrolysis than that of maize straw. These results could provide some guidances on the control of NO x emissions from biomass energy utilization. • Nitrogen distribution and migration behaviors in pyrolysis products of maple wood and maize straw were investigated. • Nitrogen in chars showed great thermal stability in maize straw. • NH 3 was the dominant NO x precursors from the pyrolysis of the two biomass species, with more than 85% of the total NH 3 -N yield was produced in the devolatilization stage. • Higher yields of NO x precursors-N were observed from maple wood pyrolysis than that of maize straw under the same temperature. [ABSTRACT FROM AUTHOR]