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Pulsed-field ablation (PFA) is a nonthermal method for achieving selective cell death with little inflammation response. However, there are no reports of PFA for septal reduction therapy (SRT). The purpose of this study was to investigate the effectiveness and safety of PFA for SRT. A novel transvenous intraseptal PFA method with 3-dimensional (3D) guidance was introduced in Yorkshire pigs. Electrocardiographic parameters, transthoracic echocardiography, and histopathology were used to evaluated. The maximum injury diameter of intramyocardial PFA increased with electric field intensity. After PFA, bipolar electrogram amplitude and pacing threshold measured by the PFA electrodes significantly decreased (F = 6.945, P =.007) or increased (F = 5.842, P =.024), respectively. In the ablated septal region, motion amplitude and systolic wall thickening rate significantly decreased and remained at low levels (motion amplitude: F = 20.793, P =.000; systolic wall thickening rate: F = 14.343, P =.000); however, septal thickness did not significantly change after PFA (F = 1.503, P =.248). Histologic examination showed specific cardiomyocyte death with gradually increased hyperchromatic cytoplasm and nuclear pyknosis, without obvious inflammatory cell infiltration in acute phase. TUNEL stain for fragmented DNA showed extensively positive in the ablation region 24 hours after PFA. During PFA, no sustained ventricular arrhythmia or atrioventricular conduction block occurred. A novel intraseptal PFA method with 3D guidance was described. Intraseptal PFA resulted in effective myocardial injury and local hypokinesis without significant acute edema. Histologic examination showed widely programmed cardiomyocyte death with little inflammatory cell infiltration. [Display omitted] [ABSTRACT FROM AUTHOR]

• SGLT2i significantly reduced MACE compared with placebo. • SGLT2i could reduced cardiovascular death and all-cause mortality events. • SGLT2i is effective as secondary prevention of cardiovascular outcomes. Many clinical studies have shown that sodium-glucose cotransporter 2 inhibitors (SGLT2i) reduce cardiovascular risks, such as heart failure, myocardial infarction and cardiovascular death. To investigate the use of SGLT2i for the prevention of primary and secondary cardiovascular outcomes. Pubmed, Embase and Cochrane libraries databases were searched and meta-analysis was performed using Revman 5.4. Eleven studies with a total of 34,058 cases were analyzed. SGLT2i significantly reduced major adverse cardiovascular events (MACE) in patients with prior myocardial infarction (MI) (OR 0.83, 95% CI 0.73–0.94, p = 0.004), no prior MI (OR 0. 82, 95% CI 0.74–0.90, p <0.0001), prior coronary atherosclerotic disease (CAD) (OR 0.82, 95% CI 0.73–0.93, p = 0.001) and no prior CAD (OR 0.82, 95% CI 0.76–0.91, p = 0.0002) compared with placebo. In addition, SGLT2i significantly reduced hospitalization due to heart failure (HF) in patients with prior MI (OR 0.69, 95% CI 0.55–0.87, p = 0.001), no prior MI (OR 0.63, 95% CI 0.55–0. 72, p <0.00001), prior CAD (OR 0.65, 95% CI 0.53–0.79, p <0.0001) and no prior CAD (OR 0.65, 95% CI 0.56–0.75, p <0.00001) compared with placebo. SGLT2i reduced cardiovascular mortality and all-cause mortality events. MI (OR 0.79, 95% CI 0.70–0.88, p <0.0001), renal damage (OR 0.73, 95% CI 0.58–0.91, p = 0.004), all-cause hospitalization (OR 0.89, 95% CI 0.83–0.96, p = 0.002), systolic and diastolic blood pressure were all significantly reduced in patients receiving SGLT2i. SGLT2i was effective in prevention of primary and secondary cardiovascular outcomes. [ABSTRACT FROM AUTHOR]

The direct graphite-to-diamond transformation mechanism has been a subject of intense study and remains debated concerning the initial stages of the conversion, the intermediate phases, and their transformation pathways. Here, we successfully recover samples at the early conversion stage by tuning high-pressure/high-temperature conditions and reveal direct evidence supporting the nucleation-growth mechanism. Atomistic observations show that intermediate orthorhombic graphite phase mediates the growth of diamond nuclei. Furthermore, we observe that quenchable orthorhombic and rhombohedra graphite are stabilized in buckled graphite at lower temperatures. These intermediate phases are further converted into hexagonal and cubic diamond at higher temperatures following energetically favorable pathways in the order: graphite → orthorhombic graphite → hexagonal diamond, graphite → orthorhombic graphite → cubic diamond, graphite → rhombohedra graphite → cubic diamond. These results significantly improve our understanding of the transformation mechanism, enabling the synthesis of different high-quality forms of diamond from graphite. [Display omitted] [ABSTRACT FROM AUTHOR]

Surface sediments and sediment core had been collected from Erhai Lake, Southwest China to study the concentrations, toxicity risks, and sources of polycyclic aromatic hydrocarbons (PAHs). The average concentrations of Σ 16 PAHs, seven carcinogenic PAHs (carPAHs), and carcinogenic toxic equivalents (TEQcar) in the surface sediments and sediment core were 1634.50 ± 488.56 ng g−1 and 436.72 ± 128.17 ng g−1, 67.18–293.65 ng g−1 and 91.07–265.90 ng g−1, and 34.89 ± 13.17 ng g−1 and 36.99 ± 7.52 ng g−1, respectively. The Σ 16 PAHs and carPAHs concentrations in surface sediments were higher in the southern lake. The Σ 16 PAHs and TEQcar in the sediment core peaked in the 2010s and 1980s. The spatiotemporal variations in TEQcar and carPAHs were similar. Positive matrix factorization revealed that traffic emissions contributed 35.71 % of the TEQcar, whereas coal and biomass combustion contributed 12.89 % in the surface sediments. The contribution of gasoline and fossil fuel to TEQcar significantly increased from 19.2 % (1890s) to 66.5 % (1990s), that of benz[ a ]pyrene (coal combustion) decreased, and those of benz[ b ]fluoranthene and indeno[1,2,3- cd ]pyrene (petroleum combustion and traffic emissions) increased from 1.92 % to 3.93 % and from 1.54 % to 2.52 % in the sediment cores, respectively, owing to changes in energy consumption. • Spatio-temporal distributions of Σ 16 PAHs, carPAHs, and TEQ in Erhai Lake sediments were investigated. • Sources of PAHs concentrations and TEQcar were quantitatively apportioned via the PMF model. • TEQ BaP and TEQ DbahA increased over last four decades but decreased in recent years. • Energy consumption, especially fossil fuel combustion, greatly contributed TEQ. [ABSTRACT FROM AUTHOR]

Abstract: The optical anisotropic states in the azo-dye Disperse Red 13 doped poly(methyl methacrylate) polymeric film are induced by polarized light and the nonlinear refractive index in these states are studied by the Z-scan technique. It is found that the n 2 of the sample can be controlled by changing both the polarization direction and the intensity of the 514nm light. Photo-induced isomerization and reorientation of azo chromophores in polymer matrices are used to explain the results. [ABSTRACT FROM AUTHOR]

• A multimodal fusion-based compressed ultrafast photography was proposed, which simultaneously records the same dynamic scene with different imaging modes. • Transient images were first utilized to assist in the reconstruction of CUP. • An untrained neural network-based reconstruction algorithm was proposed for conducting image reconstruction of MF-CUP. • The superiority of the proposed method in temporal and spatial fidelity was verified in simulations and experiments. Featuring high frame rate and large sequence depth in a single shot, compressed ultrafast photography (CUP) has emerged as an outstanding tool for observing ultrafast phenomena, especially those unrepeatable or irreversible ones. However, the lower image quality in CUP due to high data compressive ratio has always been a tough issue, hampering its further applications in capturing the transient scenes with fine structural information. To overcome this disadvantage in CUP, here we report a multimodal fusion-based compressed ultrafast photography to achieve high-fidelity ultrafast imaging, termed MF-CUP. MF-CUP simultaneously records the dynamic scenes with three different imaging models, involving CUP, transient imaging and spatiotemporal integration imaging. Attributed to the joint acquisition of the dynamic scenes from different imaging models and the multimodal fusion image reconstruction algorithm enabled by untrained neural network, MF-CUP acquires the higher fidelity in both spatial and temporal domains compared with traditional CUP. Both the simulation and experimental results demonstrate that MF-CUP can effectively enhance the accuracy and quality of reconstructed images. Given this high-fidelity imaging ability of MF-CUP, it will provide a powerful tool for the detection of ultrafast dynamics with fine details. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM) is a ubiquitous group of organic compounds in rainwater that plays vital roles in the biogeochemical cycle. However, little is known about its chemical composition, optical characterization, potential sources, and controlling mechanisms in peri-urban atmospheric rainwater. One-year rainfall samples were collected between September 2018 and August 2019 in a Nanjing suburb. Stoichiometric, ultraviolet–visible (UV–Vis) absorption, and three-dimensional fluorescence excitation-emission matrix (EEM) with parallel factor analysis (PARAFAC) analyses were utilized to characterize DOM. Several proxies for DOM concentration, including dissolved organic carbon (DOC), dissolved organic nitrogen (DON), and absorption coefficient (a254), exhibited power-function relationships with the rainfall amount (r2 = 0.33–0.55, p < 0.001). Particularly, the DOC and a254 value showed significant seasonal variability, with lower value in two wet seasons (winter and summer) than in the dry seasons (autumn and spring). The annual wet depositional (WD) flux of DOC in the Xianlin (XL) site was calculated as 1.68 g C m−2 yr−1, agreeing with the range of global WD flux values. Two terrestrial humic-like components (C1–C2), one microbial humic-like component (C3), and one tryptophan-like component (C4) were identified by EEM-PARAFAC in rainwater DOM. The results of the specific absorption indices (SUVA 254, S R) and PARAFAC component analyses revealed that summer DOM samples had lower fluorescence intensities, aromatic contents, and molecular sizes. Principal component analysis (PCA) based on DOM indices showed that rainwater DOM had predominantly terrestrial humic origins, while this characteristic became slightly weaker in summer. The quantity and quality of rainwater DOM were closely related to meteorological variables (i.e., air mass, rainfall amount, and solar radiation) as well as anthropogenic activities. This study could improve the understanding of the quantity and quality of rainwater DOM on carbon budgets and biogeochemical cycling from some new insights of optical proxies about different fates of rainwater DOM under complex controlling mechanisms. Image 1 • Concentration and chemical structure of rainwater DOM showed seasonal variations. • Climatic factors and human activities were dominant effects on rainwater DOM. • Rainwater DOM components were mainly generated from humic substances. • Wet inorganic N in atmosphere was closely coupled with rainwater DOM. [ABSTRACT FROM AUTHOR]

Abstract Perovskite oxides are promising multi-functional materials with enhanced physical and chemical properties. In this study, high-crystalline SrMnO 3 perovskite oxide nanofibers have been successfully synthesized by sol–gel electrospinning followed by calcination at different temperatures, using polyvinylpyrrolidone as a sacrificial polymeric binder. The change in porosity and grain size with calcination temperature imparted a substantial effect on the electrochemical properties of the obtained SrMnO 3 nanofibers. The SrMnO 3 nanofiber electrode calcined at 700 °C exhibits an electrochemical capacitance of 321.7 F g−1 at a discharge current density of 0.5 A g−1. The effect of doping Ba/Ca on Sr, and Co/Fe/Ni on Mn, respectively, on the specific capacitance of SrMnO 3 nanofibers is studied. 20 mol% Ba loading shows the best performance as a supercapacitor electrode with a specific capacitance of 446.8 F g−1 at a discharge current density of 0.5 A g−1. The nanofibers retained 87% its initial capacitance after 5000 successive cycles. The device fabricated using the nanofibers show an energy density of 37.3 W h kg−1 at a power density of 400 W kg−1, and it is retained as 15.7 W h kg−1 even at a high-power density of 8006 W kg−1, indicating the potential of this electrode material for high-rate charge/discharge operations in supercapacitors. Graphical abstract fx1 Highlights • The first study of SrMnO 3 perovskite nanofibers for supercapacitor application. • Evaluation of effects of Ba, Ca, Co, Fe and Ni doping and doping levels. • High capacitance of 446.8 F g-1 of SrMnO 3 doped with 20% Ba at a discharge current density of 0.5 A g−1. • Energy density of 37.3 W h kg−1 at power density of 400 W kg−1 which is retained as 15.7 W h kg−1 at 8006 W kg−1. • High cycling stability retaining 87% of its initial capacitance after 5000 successive cycles. [ABSTRACT FROM AUTHOR]

Particulate organic carbon (POC) sources, which regulate dissolved organic carbon, sediment organic carbon, and inorganic carbon via deposition, degradation, and mineralization, play an important role in lake ecosystems. Linear or Bayesian algorithms on isotope and n-alkanes have been widely used to identify the source proportion of organic carbon. However, the applicability of these methods is ambiguous because of the unilateral advantages of each model and trace factors. To test the applicability of the various methods for identifying POC sources, we analyzed dual isotopes and n-alkanes in surface water samples of Lake Taihu, and Multi-source mixing model and Bayesian mixing model were used to distinguish between endogenous and exogenous contributions. Carbon isotope presented a clear advantage in West Taihu (-21.85 ± 0.78‰) and Southwest Taih (-22.61 ± 1.35‰); nitrogen isotope also showed high values in Meiliang Bay (9.76 ± 0.92‰). The majority of the lake was dominated by short-chain n-alkanes, except for East Taihu Lake (dominated by medium-chain n-alkanes) and areas with riverine input (dominated by long-chain n-alkanes). Different principles between the Bayesian mixing model (based on the Markov Chain Monte Carlo algorithm) and the Multi-source mixing model (based on linear estimation) caused discrepancies in the estimations of source contributions. But the fraction of chemical compounds during the migration process, and the overlap of potential sources play important role in the inconsistency of results. The estimations from the different models were consistent in indicating the dominance of endogenous organic carbon in Lake Taihu (mean of 60.18 ± 20.26%), particularly in the north and western regions (West Taihu, Meiliang Bay, and Southwest Taihu). This was likely due to algal aggregation influenced by human activities and climatic factors. [ABSTRACT FROM AUTHOR]

Sixteen polycyclic aromatic hydrocarbons (PAHs) in a sediment core from Dianchi Lake, southwest China, were analysed. The influence of changes in China's energy structure for 2–6 ringed PAHs was investigated to assess sources and the impact of socioeconomic development on temporal changes in concentrations. The concentration of the ΣPAH 16 ranged from 746 to 2293 ng g−1. Prior to the 1960s relatively low concentrations of the ΣPAH 16 and a larger proportion of 2–3-ring PAHs indicated that biomass combustion was the main source of PAHs. A rapid increase in the concentrations of 2–3 ring PAHs between 1975 and 2004 was attributed to population growth and coal consumption. A declining trend since 2004 was interpreted as being due to local changes in household energy usage. Increased concentrations of 4-ring PAH between 1975–2005 and 5–6-ring PAHs between the 1980s to 2004 showed correlations with increased coal consumption and the number of motor vehicles, respectively. These were caused by rapid urbanization and industrialization in the Dianchi watershed following the implementation of the Reform and Open Policy in 1978. A subsequent decline in the concentrations of 4-ring and 5–6-ring PAHs may have been due to decreased coal consumption and improvements in emission standards, respectively. Source apportionment by a PMF model revealed that coal combustion (29.2%), vehicle emissions (24.2%), petrogenic sources (21.8%), and biomass combustion (24.9%) were the sources of PAHs in the lake sediment core, and that coal combustion was the most important regional source of PAHs pollution. Image 1 • Sixteen PAHs from Dianchi lake sediment, a plateau lake in China, were studied. • Sediment record of PAHs reflect trends in GDP and total energy consumption. • Sediment records of different PAH rings can reflect the changes of energy structure. • Coal and biomass combustion, vehicle emissions and petrogenic were the PAHs sources. • Time trend of factor contributions are consistent with economic parameters. [ABSTRACT FROM AUTHOR]