The impact of empirical Marshall vein ethanol infusion as a first-choice intraoperative strategy on the long-term outcomes in patients with persistent atrial fibrillation undergoing mitral isthmus ablation.

Background: Marshall vein ethanol infusion (MVEI) as an additional therapy to conventional catheter ablation (CA) has been proved to be efficacious in patients with persistent atrial fibrillation (PeAF). However, whether empirical MVEI could be the first-line strategy in mitral isthmus (MI) ablation has seldom been investigated. Here, we aim to compare the efficacy, safety, and long-term outcomes between provisional and empirical MVEI in PeAF patients undergoing the index MI ablation procedure. Methods: We enrolled 133 patients with PeAF either in the provisional group (n = 38, MVEI was performed when conventional endocardial and/or epicardial ablation procedures were inadequate to achieve bidirectional MI block) or in the empirical group (n = 95, MVEI was performed empirically before MI CA). Results: All of the baseline characteristics were comparable. Less spontaneous or inducible atrial tachycardias (ATs) were encountered in the empirical group of patients (P < 0.001). More epicardial ablations were applied (26.3% vs. 9.5%, P = 0.016) and a higher incidence of CA-facilitated restoration of sinus rhythm was recorded (86.8% vs. 11.7%, P < 0.001) in the provisional group of patients. Although more fluoroscopy time (6.4[4.2, 9.3] vs. 9.5[5.9, 11.6] min, P = 0.019) and radiation exposure (69.0[25.3, 160.2] vs. 122.0[62.5, 234.1] mGy, P = 0.010) were documented in the empirical group with comparable procedure time, less time (455.9 ± 192.2 vs. 366.5 ± 161.3 s, P = 0.038) was consumed to achieve bidirectional MI block during endocardial ablation in the provisional group. Incidences of procedure-related complications were similar between the two groups. During a 16.5 ± 4.4-month follow-up, the empirical group of patients showed a significantly higher rate of freedom from AT recurrence (95.8% vs. 81.6%, log-rank P = 0.003), while the rate of freedom from AF or atrial tachyarrhythmias (combining AF and AT) was similar. Both univariate (HR 0.19, 95% CI 0.05-0.64, P = 0.008) and multivariate (HR 0.25, 95% CI 0.07-0.92, P = 0.037) Cox regression analyses indicated that empirical MVEI was independently associated with lower long-term AT recurrence. Conclusion: Among patients with PeAF who underwent the index MI ablation procedure, empirical MVEI could reduce endocardial MI ablation time and provide greater long-term freedom from AT recurrence.

A "Biconcave-Alleviated" Strategy to Construct Aspergillus niger-Derived Carbon/MoS2 for Ultrastable Sodium Ion Storage.

Two-dimensional layered materials commonly face hindered electron transfer and poor structure stability, thus limiting their application in high-rate and long-term sodium ion batteries. In the current study, we adopt finite element simulation to guide the rational design of nanostructures. By calculating the von Mises stress distribution of a series of carbon materials, we find that the hollow biconcave structure could effectively alleviate the stress concentration resulting from expansion. Accordingly, we propose a biconcave-alleviated strategy based on the Aspergillus niger-derived carbon (ANDC) to construct ANDC/MoS2 with a hollow biconcave structure. The ANDC/MoS2 is endowed with an excellent long-term cyclability as an anode of sodium ion batteries, delivering a discharge capacity of 496 mAh g-1 after 1000 cycles at 1 A g-1. A capacity retention rate of 94.5% is achieved, an increase of almost seven times compared with the bare MoS2 nanosheets. Even at a high current density of 5 A g-1, a reversible discharge capacity around 400 mAh g-1 is maintained after 300 cycles. ANDC/MoS2 could also be used for efficient lithium storage. By using in situ TEM, we further reveal that the hollow biconcave structure of ANDC/MoS2 has enabled stable and fast sodiation/desodiation.

Cubic MnS-FeS2 Composites Derived from a Prussian Blue Analogue as Anode Materials for Sodium-Ion Batteries with Long-Term Cycle Stability.

Cubic N,S codoped carbon coating MnS-FeS2 composites (MnS-FeS2@NSC) with a hollow structure were prepared and used as anode materials for sodium-ion batteries. MnS-FeS2@NSC exhibits excellent cycle performance and high rate capability and delivered a reversible capacity of 501.0 mAh g-1 after 800 cycles at a current density of 0.1 A g-1 with a capacity retention of 81%. More importantly, the MnS-FeS2@NSC anode holds long-term cycle stability; the capacity can remain 134.0 mAh g-1 after 14 500 cycles at 4 A g-1. Kinetic analysis demonstrated that Na+ storage follows a pseudocapacitive dominating process, which is ascribed to the origin of the outstanding rate performance of the MnS-FeS2@NSC material. The enhancement of electrochemical performance is attributed to the hollow structure and the N,S codoped carbon coating structure, which can reduce the diffusion distance for sodium ions and electrons, alleviate volume expansion during sodium-ion insertion/extraction, and retain the structural integrity effectively. Furthermore, a two-step sodiation processes with FeS2 sodiation prior to MnS was demonstrated by X-ray diffraction (XRD), and the electrochemical impedance spectroscopy (EIS) spectra might indicate that the accumulation of the metallic elements in the preconversion reaction can accelerate the transfer of electrons and ions in the further conversion process.

Shaping and Edge Engineering of Few-Layered Freestanding Graphene Sheets in a Transmission Electron Microscope.

Full exploitation of graphene's superior properties requires the ability to precisely control its morphology and edge structures. We present such a structure-tailoring approach via controlled atom removal from graphene edges. With the use of a graphitic-carbon-capped tungsten nanoelectrode as a noncontact "milling" tool in a transmission electron microscope, graphene edge atoms approached by the tool tip are locally evaporated, thus allowing a freestanding graphene sheet to be tailored with high precision and flexibility. A threshold for the tip voltage of 3.6 ± 0.4 V, independent of polarity, is found to be the determining factor that triggers the controlled etching process. The dominant mechanisms involve weakening of carbon-carbon bonds through the interband excitation induced by tunneling electrons, assisted with a resistive-heating effect enhanced by high electric field, as elaborated by first-principles calculations. In addition to the precise shape and size control, this tip-based method enables fabrication of graphene edges with specific chiralities, such as "armchair" or "zigzag" types. The as-obtained edges can be further "polished" to become entirely atomically smooth via edge evaporation/reconstruction induced by in situ TEM Joule annealing. We finally demonstrate the potential of this technique for practical uses through creating a graphene-based point electron source, whose field emission characteristics can effectively be tuned via modifying its geometry.

Every Pixel Counts ++: Joint Learning of Geometry and Motion with 3D Holistic Understanding.

Learning to estimate 3D geometry in a single frame and optical flow from consecutive frames by watching unlabeled videos via deep convolutional network has made significant progress recently. Current state-of-the-art (SoTA) methods treat the two tasks independently. One important assumption of the existing depth estimation methods is that the scenes contain no moving object. In this paper, we propose to address the two tasks as a whole, i.e. to jointly understand per-pixel 3D geometry and motion. This eliminates the need of static scene assumption and enforces the inherent geometrical consistency during the learning process, yielding significantly improved results for both tasks. We call our method as "Every Pixel Counts++" or "EPC++". Various loss terms are formulated to jointly supervise the learning across geometrical cues and effective adaptive training strategy is proposed to achieve better performance. Comprehensive experiments were conducted on datasets with different scenes, including driving scenario (KITTI 2012 and KITTI 2015 datasets), mixed outdoor/indoor scenes (Make3D) and synthetic animation (MPI Sintel dataset). Performance on the five tasks of depth estimation, optical flow estimation, odometry, moving object segmentation and scene flow estimation shows that our approach outperforms other SoTA methods, demonstrating the effectiveness of each module of our proposed method.