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• Effects of vortex generator on subcooled flow boiling are investigated. • Vortex generator accelerates the bubble departure from the heating surface. • The maximum increase of the heat transfer coefficient by vortex generator is 8.4×103 W m-2 K-1. • A new correlation targeting vortex-enhanced subcooled flow boiling is developed. Subcooled flow boiling in a micro-channel is a mainstream heat dissipation way for high-heat-flux electronics. This paper presents a new idea to enhance heat transfer of subcooled flow boiling, i.e. accelerating bubble departure from the heating wall of flow channel by inserting a vortex generator; and the effects of vortex generator positions and working fluid conditions on the heat transfer characteristics are experimentally studied. The shape of the vortex generator is helix with the length, pitch, helix diameter and wire diameter of 22.5 mm, 1.8 mm, 1.8 mm and 0.2 mm, respectively. The vortex generator positions in the experiments include the front, the middle and the end of the flow channel; and the working fluid conditions include the mass fluxes of 1000 – 3500 kg m−2 s−1 and the inlet subcooling degrees of 30–50 K. It is found that the vortex generator could accelerate the bubble departure from the wall, and thus enhance the heat transfer in subcooled flow boiling. The maximum increase of the heat transfer coefficient of the all vortex channel is 8.4 × 103 W m−2 s−1, and the maximum increase rate of critical heat flux (CHF) is 21.8%. Furthermore, a new correlation to predict the heat transfer coefficients of vortex enhanced subcooled flow boiling was developed. The predictions by the new correlation could agree with 92% of the experimental data within a deviation of ± 30%, and the average deviation is 13.7%. [ABSTRACT FROM AUTHOR]

Sodium intake shows a positive correlation with blood pressure, resulting in an increased risk for cardiovascular diseases (CVD). Salt reduction is a key step toward the WHO's goal of 25% reduction in mortality from non‐communicable diseases (NCDs) by 2025. This study aims to assess the current condition and temporal changes of the global CVD burden due to high sodium intake (HSI). We extracted data from the Global Burden of Disease (GBD) study 2019. The numbers and age‐standardized rates of mortality and disability‐adjusted life‐years (DALYs), stratified by location, sex, and socio‐demographic Index (SDI), were used to assess the high sodium intake attributable CVD burden from 1990 to 2019. The relationship between the DALYs rates and related factors was evaluated by stepwise multiple linear regression analysis. Globally, in 2019, the deaths and DALYs of HSI‐related CVD were 1.72 million and 40.54 million, respectively, increasing by 41.08% and 33.06% from 1990. Meanwhile, the corresponding mortality and DALYs rates dropped by 35.1% and 35.2%, respectively. The high‐middle and middle SDI quintiles bore almost two‐thirds of CVD burden caused by HSI. And the leading cause of HSI attributable CVD burden was ischemic heart disease. Universal health coverage (UHC) was associated with the DALYs rates after adjustment. From 1990 to 2019, the global CVD burden attributable to HSI has declined with spatiotemporal and sexual heterogeneity. However, it remains a major public health challenge because of the increasing absolute numbers. Improving UHC serves as an effective strategy to reduce the HSI‐related CVD burden. [ABSTRACT FROM AUTHOR]

Atrial fibrillation/atrial flutter (AF/AFL) has progressed to be a public health concern, and high systolic blood pressure (HSBP) remains the leading risk factor for AF/AFL. This study estimated the HSBP attributable AF/AFL burden based on the data from the Global Burden of Disease (GBD) study 2019. Numbers, age‐standardized rates (ASR) of deaths, disability‐adjusted life years (DALYs), and corresponding estimated annual percentage change (EAPC) were analyzed by age, sex, sociodemographic index (SDI), and locations. Gini coefficient was calculated to evaluate health inequality. Globally, HSBP‐related AF/AFL caused 107 091 deaths and 3 337 876 DALYs in 2019, an increase of 142.5% and 105.9% from 1990, respectively. The corresponding mortality and DALYs ASR declined by 5.8% and 7.7%. High‐income Asia Pacific experienced the greatest decrease in mortality and DALYs ASR, whereas the largest increase was observed in Andean Latin America. Almost half of the HSBP‐related AF/AFL burden was carried by high and high‐middle SDI regions, and it was experiencing a shift to lower SDI regions. A negative correlation was detected between EAPC and SDI. Females and elderly people tended to have a higher AF/AFL burden, whereas young adults (30–49 years old) experienced an annual increase in AF/AFL burden. The Gini index of DALYs rate decreased from 0.224 in 1990 to 0.183 in 2019. Despite improved inequality having been observed over the past decades, the HSBP‐related AF/AFL burden varied across regions, sexes, and ages. Cost‐effective preventive, diagnostic, and therapeutic tools are required to be implemented in less developed regions. [ABSTRACT FROM AUTHOR]

Context: Idiopathic ventricular arrhythmias (IVAs) are a spectrum of ventricular arrhythmia (VA) without structural heart disease (SHD), that includes premature ventricular contractions (PVCs) and ventricular tachycardia (VT). The clinical characteristics of patients with PVCs or VT remain unclear, including distribution of the origin of arrhythmias, age and gender differences, comorbidities, laboratory tests, and electrocardiographic parameters.Objective: The study intended to compare the clinical characteristics of the right ventricular outflow tract (RVOT)- and left ventricular outflow tract (LVOT)-VT of a large group of consecutive patients, to investigate the distribution of the origin of the arrhythmias, age and gender differences, comorbidities, laboratory-examination results, and echocardiographic parameters.Methods: The research team designed a retrospective study to collect data on the above-mentioned variables.Setting: The study occurred at the Second Hospital of Hebei Medical University in Shijiazhuang, China.Participants: Participants were 774 patients with symptomatic ventricular arrhythmias, 328 males and 446 females with the mean age of 48.6 ± 15.7 years, who underwent catheter ablation between January 2015 and January 2019. Participants were divided into the right ventricular outflow tract (RVOT) group and left ventricular outflow tract (LVOT) group, according to the different origins of their arrhythmias, with 428 participants in the RVOT group and 180 in the LVOT group.Outcome Measures: The research team collected and analyzed the data for the original sites of the IVAs; ages; genders; comorbidities; laboratory examinations, including routine blood tests, liver function, kidney function, blood lipid and potassium; and echocardiographic parameters.Results: Among the 774 participants, 76 had experienced VTs and 698 PVCs. The original site of IVAs was 2.38 times more likely to be in the RVOT than the LVOT, with the ratio for RVOT/LVOT = 2.38. IVAs usually occurred in participants between 50 and 70 years old and exhibited a decreasing incidence after 70 years of age. IVAs derived from the His bundle were more common in older participants, with a mean age of 60.4 ± 10.4 years, while IVAs derived from the fascicular were more common in younger patients, with a mean age of 36.08 ± 16.01 years. Compared with the LVOT group, the RVOT group was younger, 51.91 ± 14.65 years vs 46.95 ± 14.95 years, respectively (P < .001). PVCs in the RVOT group were more common in women, with the ratio of females/males = 2.10, and no gender difference existed in the overall incidence of IVAs in the LVOT group (P > .05). The most common cardiovascular comorbidities of outflow tract ventricular arrhythmias (OTVAs) were hypertension, coronary heart disease, and hyperlipidemia, while the most common noncardiovascular comorbidities were diabetes, ischemic stroke, and thyroid disease. The red-blood-cell counts, hemoglobin, creatinine, and gamma-glutamyl transpeptidase (GGT) of the LVOT group were higher than those from the RVOT, with P = .008, P = .009, P = .001, and P < .001, respectively. The left atrial diameter (LAD), left ventricular end-diastolic diameter (LVEDD), interventricular septal thickness (IVS), and left ventricular posterior wall thickness (LVPWT) in the LVOT group were larger than those in the RVOT group (P <.001), while the LVOT group's left ventricular ejection fraction (LVEF%) was lower than that of the RVOT group.Conclusions: The outflow tract served as the major original site of IVAs, and significant differences existed between participants in the LVOT and RVOT groups in age; gender; comorbidities; results of laboratory examinations, including red-blood-cell counts, hemoglobin, creatinine, and GGT; and echocardiographic parameters, including LVEF%, LAD, LVEDD, IVS, and LVPWT. [ABSTRACT FROM AUTHOR]