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We are concerned with the Riemann problem for the isentropic Euler equations of mixed type in the dark energy fluid. This system is non-strictly hyperbolic on the boundary curve of elliptic and hyperbolic regions. We obtain the unique admissible shock waves by utilizing the viscosity criterion. Assuming fixed left states are in the elliptic and hyperbolic regions, respectively, we construct the unique Riemann solution for the mixed-type models with the initial right state in some feasible regions. Finally, we present numerical simulations which are consistent with our theoretical results. [ABSTRACT FROM AUTHOR]

Background Oesophageal fistula is a rare complication of catheter ablation of atrial fibrillation with most fistulas being atrio-oesophageal fistulas, but oesophageal–pericardial fistula can also happen in the absence of atrial perforation. Case summary A 68-year-old male patient presented with chest pain 10 days after catheter ablation of paroxysmal atrial fibrillation. He was discharged after an initial negative workup that included a CT chest without contrast. He later presented again with severe chest pain and fever and was found to have an oesophageal–pericardial fistula. He underwent surgical and endoscopic treatment with good recovery. Discussion Patients with oesophago-pericardial fistulas often have delayed presentation 1–4 weeks after the ablation procedure. Early diagnosis can be challenging. CT with oral and intravenous contrast is often used for diagnosis. Treatment often includes antibiotics, surgical or interventional drainage of infected spaces with oesophageal repair, clipping or stenting. In contrast to atrio-oesophageal fistulas that carry a high mortality rate, mortality for oesophago-pericardial fistulas appears to be much lower. [ABSTRACT FROM AUTHOR]

We propose a concept of a high-order mode (HOM) pass filter based on the inverse-designed mode-routing, which enables an ultra-compact footprint and broad bandwidth. To validate the concept, we experimentally demonstrate two types of HOM pass filters using the direct-binary search topology optimization algorithm. In the first HOM pass filter, the mode-routing region is constructed using an inverse-designed adiabatic coupler, while the second filter utilizes a tapered asymmetric directional coupler. The subwavelength units based on the functional regions of both filters have an ultra-compact footprint of 4 µm × 800 nm. The experimental results indicate that the insertion losses of two HOM-pass filters are 3.13 and 1.94 dB, respectively, and their mode cross-talks are −15.8 and −27.36 dB at the center wavelength of 1550 nm. Both HOM pass filters exhibit high performance over a broad bandwidth of 130 nm. [ABSTRACT FROM AUTHOR]

Background: Extensive research has indicated that higher levels of glycated hemoglobin (HbA1c) are associated with poor cognitive performance regardless of the presence of diabetes. To our knowledge, the association between HbA1c levels and cognitive decline in patients with alcohol use disorder is not well understood. This study aimed to investigate whether HbA1c was associated with cognitive impairment in patients with alcohol use disorder. Methods: Patients admitted to the Psychiatry Department of the Third Hospital of Quzhou with a confirmed diagnosis of alcohol-related cognitive impairment were recruited between January 2019 and February 2022. Their HbA1c levels were measured, and they completed the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) after at least one week of monitored abstinence from alcohol. Univariate linear regression, multivariate linear regression and generalized additive models (GAMs) were used to investigate the association of HbA1c with MMSE and MoCA scores. Results: In total, 227 patients were included. Univariate and multivariate regression analyses suggested that HbA1c was negatively associated with MMSE and MoCA scores after adjustment for potential confounders (P < 0.05). The GAM analysis revealed that the relationships between the HbA1c level and the MMSE and MoCA scores were bell-shaped. The inflection points were 5.3% and 5.2% for the MMSE and MoCA respectively. Conclusion: The results of this study suggest that HbA1c levels are significantly related to cognitive impairment in patients with alcohol use disorder. Future studies are required to determine the effects of optimal glucose control in people with alcohol use disorder. [ABSTRACT FROM AUTHOR]

In this paper, we study the global L∞$L^{\infty }$ entropy solutions for the Cauchy problem of the isentropic gas dynamics system in a general nozzle with bounded initial date. First, we apply for the flux‐approximation technique coupled with the classical viscosity method to obtain the L∞$L^{\infty }$ estimates of the viscosity solutions. Second, we prove the pointwise convergence of the approximation solutions by using the compactness framework for any adiabatic exponent γ>1$\gamma >1$. [ABSTRACT FROM AUTHOR]

Herein, we present the initial application of the NOAA-EPA Atmosphere-Chemistry Coupler (NACC) in the cloud ("NACC-Cloud", version 1), which processes NOAA's operational Global Forecast System version 16 (GFSv16) meteorology on-demand and produces model-ready meteorological files needed to drive U.S. EPA's Community Multiscale Air Quality (CMAQ) model. NACC is adapted from the U.S. EPA's Meteorology-Chemistry Interface Processor version 5 (MCIPv5) and is used as the primary model coupler in the current operational NWS/NOAA air quality forecasting model. The development and use of NACC-Cloud in this work are critical to provide the scientific community streamlined access to NOAA's operational GFSv16 data and user-defined processing and download of model-ready, meteorological input for any regional CMAQ domain worldwide. The NACC-Cloud system was implemented on the Amazon® Web Services High-Performance Computing platform, and results from this work show that the NACC-Cloud system is immediately beneficial to the air quality modeling community worldwide. [ABSTRACT FROM AUTHOR]

We study the cavitation and concentration of the Riemann solutions for the improved Aw–Rascle–Zhang (IARZ) model in dusty gas with a non-genuinely nonlinear field. The Riemann solutions containing composite waves are constructed by Liu-entropy condition first. Second, we investigate the limits of the inflection point and tangent point along the 1-family wave curve and find that the composite waves tend to elementary waves as pressure vanishes. Third, we obtain the limiting behavior of the Riemann solutions and observe the formation of δ-shock wave and vacuum as pressure vanishes. We conclude that the limit of Riemann solutions of the IARZ model is not the Riemann solutions of the limit of the IARZ model. The phenomenon is consistent with the work of C. Shen and M. Sun ["Formation of delta-shocks and vacuum states in the vanishing pressure limit of solutions to the Aw–Rascle model," J. Differ. Equations 249, 3024–3051 (2010)]. Finally, we perform some numerical simulations to verify our theoretical analysis. [ABSTRACT FROM AUTHOR]

Aims The optimal strategy for persistent atrial fibrillation (PerAF) is poorly defined. We conducted a multicentre, randomized, prospective trial to compare the outcomes of different ablation strategies for PerAF. Methods and results We enrolled 450 patients and randomly assigned them in a 1:1:1 ratio to undergo pulmonary vein isolation and subsequently undergo the following three different ablation strategies: anatomical guided ablation (ANAT group, n = 150), electrogram guided ablation (EGM group, n = 150), and extensive electro-anatomical guided ablation (EXT group, n = 150). The primary endpoint was freedom from atrial fibrillation (AF) lasting longer than 30 s at 12 months after a single ablation procedure. After 12 months of follow-up, 72% (108) of patients in the EXT group were free from AF recurrence, as compared with the 64% (96) in the EGM group (P = 0.116), and 54% (81) in the ANAT group (P = 0.002). The EXT group showed less AF/atrial tachycardia recurrence than the EGM group (60% vs. 50%, P = 0.064) and the ANAT group (60% vs. 37.3%, P < 0.001). The EXT group showed the highest rate of AF termination (66.7%), followed by 56.7% in the EGM group, and 20.7% in the ANAT group. The AF termination signified less AF recurrence at 12 months compared to patients without AF termination (30.1% vs. 42.7%, P = 0.008). Safety endpoints did not differ significantly between the three groups (P = 0.924). Conclusions Electro-anatomical guided ablation achieved the most favourable outcomes among the three ablation strategies. The AF termination is a reliable ablation endpoint. [ABSTRACT FROM AUTHOR]

Purpose: Understanding of the atrial fibrillation (AF) driven by right atrial appendage (RAA) is limited. This study aimed to understand the characteristics of the AF driven by RAA and explore ablation methods.Methods: This was a retrospective study and patients who were identified as having the AF driven by RAA were reviewed. Ablation was performed during AF. Potential maps of the left and right atrium, electrophysiological examinations, and ablation methods were studied.Results: Among the 20 identified patients (mean age 67.0 ± 11.2 years; ejection fraction 62.9 ± 6.0%; LA diameter 43.1 ± 4.9 mm; RA diameter 51.7 ± 8.3 × 42.9 ± 3.7 mm), the AF cycle length in RAA (134.0 ± 10.9 ms) was the shortest, and the fastest frequency potentials were located in the RAA in 65% of patients. For the left atrium, the AF cycle length of the roof (145.5 ± 14.9 ms) was the shortest, followed by the left atrial appendage (153.7 ± 17.1 ms) and bottom (154.8 ± 11.8 ms). High-frequency potentials of RAA could be rapidly conducted to left atrium via sagittal bundle and Bachmann's bundle, and the conduction time (55.0 ± 5.0 ms) was significantly shorter than the mean bi-atrial activation time (176.7 ± 10.3 ms, P < 0.0001). AF could be terminated after ablation at the RAA base (17 patients) or mechanical stimulation within the RAA (3 patients). To date, only two patients had recurrent atrial flutter, while the remaining patients maintained sinus rhythm.Conclusion: The AF driven by RAA is characterized by high-frequency potentials in RAA, and ablation at the RAA base can achieve a satisfactory therapeutic effect. [ABSTRACT FROM AUTHOR]

In this article, we make several comparisons of Riemann solutions of compressible Euler equations in the modified Chaplygin gas state ( p = A ρ − ρ − 1 ) and classical Chaplygin gas state ( p = − ρ − 1 ). Firstly, through the analysis of characteristic method, we construct the Riemann solutions for the modified Chaplygin gas state and compare the Riemann solutions with different coefficients A. Then we obtain the reason of the occurring of delta shock waves in classical Chaplygin gas case, which is the lower bounded of 1-wave curves and the upper bounded of 3-wave curves. Moreover, by comparing the position of simple wave curves between the modified and classical Chaplygin gas state, we find that no matter how small the coefficient A is, there is an initial Riemann data, subject to that the Riemann solutions for modified Chaplygin gas state contain rarefaction waves while the Riemann solutions for classical Chaplygin gas state are delta waves, which is different from the initial expect. Finally, we present a numerical analysis consistent with the theoretical analysis. [ABSTRACT FROM AUTHOR]

Grating couplers (GCs) are important for light to couple between optical fibers and photonic integrated circuits (PICs). The Bound State in Continuum (BIC) waveguides offer new functionalities for PIC. High-Q resonators, electro-optical modulator, and photodetectors can be built on it without etching steps. Due to the special waveguide geometry of BIC waveguides, a high efficiency GC is still missing. In this work, we demonstrated a subwavelength grating (SWG) GC for BIC waveguide with a coupling efficiency of 8 dB and a 1 dB bandwidth >70 nm. The device shows ultra-broadband behavior which is extremely useful for BIC-based PICs. [ABSTRACT FROM AUTHOR]

The high power short duration (HPSD) approach was hoped to further improve the efficacy and safety in radiofrequency ablation of atrial fibrillation (AF), compared with Low power long duration (LPLD). However, the conclusion was controversial based on the previous limited data. The aim of this meta-analysis was to evaluate whether the clinical benefits of HPSD are superior to that of LPLD. The PubMed, OVID, the Cochrane Library, and Elsevier's ScienceDirect databases were searched for clinical studies to compare HPSD and LPLD approach by simple search strings benefiting to a wider screened scope. Fifteen trials with 3255 patients were included in this analysis. Pooled analyses suggested that HPSD was associated with a lower recurrence of atrial tachyarrhythmias (ATAs) at 1-year follow-up (OR: 0.49; 95% CI: 0.35 to 0.67, p <.0001), benefitted from AF recurrence reduced (OR: 0.46; 95% CI: 0.31 to 0.67, p <.0001), rather than atrial tachycardia/atrial flutter (AT/AFL), but similar at 6 months follow-up, with a decreased oesophageal thermal injury (ETI) (OR: 0.48; 95% CI: 0.30 to 0.77, p =.002). Meanwhile, the HPSD approach benefitted to increase first-pass pulmonary vein isolation (FPI) (OR: 0.47; 95% CI: 0.34 to 0.64, p <.00001) and decrease acute pulmonary vein re-isolation (PVR) (OR: 0.45; 95% CI: 0.35 to 0.58, p <.00001), both mainly embodied in left pulmonary veins (PVs). HPSD showed a decreased procedural time (SMD: −0.95; 95% CI: −1.06 to −0.85, p <.00001), ablation number for pulmonary vein isolation (PVI) (SMD: −0.41; 95% CI: −0.58 to −0.24, p <.00001) and fluoroscopy time (SMD: −0.22; 95% CI: −0.32 to −0.12, p <.0001), which benefits from PVI + additional ablation strategy (SMD: −0.33; 95% CI: −0.46 to −0.21, p <.0001). The HPSD approach was associated with decreasing post-ablation AF recurrence in the 1-year follow-up, ETI, acute PVR (increasing FPI correspondingly), procedural time, ablation number for PVI and fluoroscopy time, benefitted to improve clinical outcomes and procedural process with improved safety. [ABSTRACT FROM AUTHOR]

On-chip mode-division multiplexing (MDM) holds great promise to tackle a bandwidth crunch for optical communications and interconnects. Here, we experimentally demonstrate the mode-splitting by taking advantage of metamaterial engineering of bridged subwavelength gratings (BSWGs). The proposed mode-splitting consists of a BSWG based mode splitter, a mode multiplexer, and a mode demultiplexer. The designed device was fabricated using CMOS-compatible processes. Our fabricated device exhibits insertion losses of 0.99 and 1.8 dB in the case of manipulation of fundamental and first-order modes. The corresponding mode-crosstalks were tested to be −21.8 and −22.1 dB. The operating bandwidths were measured to be 84 and 100 nm with the mode crosstalk less than −15 dB. The proposed mode-splitting can be implemented as a promising candidate of mode manipulations for an MDM system. [ABSTRACT FROM AUTHOR]

A broadband silicon four-mode (de)multiplexer [(De)MUX] is proposed and experimentally demonstrated based on subwavelength gratings (SWGs)-assisted triple-waveguide couplers (TWCs), which can (de)multiplex TE0, TE1, TE2, and TE3 modes. The mode interaction is enhanced, benefitting from both the triple-waveguide coupling and subwavelength structures. The proposed four-mode (De)MUX is composed of three SWG-assisted TWCs connected by three linear tapers. The experimental results show that the 3-dB bandwidths are 100 nm, 76 nm, 90 nm, and 95 nm for the TE0, TE1, TE2, and TE3 modes, respectively. The corresponding insertion losses are 0.2, 1.8, 1.3, and 1.7 dB, and the mode crosstalks are -23.3, -17.7, -15.5, and -17.0 dB at the 1550 nm wavelength. The proposed device can work as a mode-(De)MUX compatible with wavelength division multiplexing (WDM) to increase the transmission capacity of on-chip optical interconnects. [ABSTRACT FROM AUTHOR]

The evolution of cost-effective hydrogen evolution reaction (HER) electrocatalysts is of great significance for the development of clean energy. Exploring effective synthesis strategies to optimize the performance of non-noble metal electrocatalysts has always attracted our attention. Herein, ultrathin coordination polymers were used as precursors to controllably synthesize two-dimensional (2D) ultrathin dual-phase transition metal selenide (TMSs)/carbon–nitrogen (CN) composites (CoSe2–NiSe2/CN) by a two-step method (first a low temperature hydrothermal method for selenization, and then high temperature calcination selenization). Benefiting from its large specific surface area (49 m2 g−1), abundant catalytically active sites and synergistic effects, CoSe2–NiSe2/CN can significantly enhance the HER catalytic activity and exhibits good electrocatalytic activity with an overpotential of 150 mV at −10 mA cm−2, and a small Tafel slope of 42 mV dec−1 in an acidic electrolyte for the HER. This work provides a new strategy for optimizing the HER catalytic activity of TMSs by preparing 2D ultrathin dual-phase TMS composite materials. [ABSTRACT FROM AUTHOR]

Regulating the structure of metal‐organic frameworks (MOFs) by adjusting the ligands reasonably is expected to enhance the interaction of MOFs on special molecules/ions, which has significant application value for the selective adsorption of guest molecules. Herein, two tricarboxylic ligands H3L−Cl and H3L−NH2 were designed and synthesized based on the ligand H3TTCA by replacing part of the benzene rings with C=C bonds and modifying the chlorine and amino groups on the 4‐position of the benzene ring. Two 3D Fe‐MOFs (UPC‐60‐Cl and UPC‐60‐NH2) with the new topology types were constructed. As the C=C bonds of the ligands have flexible torsion angles, UPC‐60‐Cl features three types of irregular 2D channels, while UPC‐60‐NH2 has a cage with two types of windows on the surface. The synergistic effect of unique channels and modification of functional groups endows UPC‐60‐Cl and UPC‐60‐NH2 with high adsorption capacity for organic dyes. Compound UPC‐60‐Cl shows high adsorption capacity for CV (147.2 mg g−1), RHB (100.3 mg g−1), and MO (220.9 mg g−1), whereas UPC‐60‐NH2 exhibits selective adsorption of MO (158.7 mg g−1). Meanwhile, based on the diverse pore structure and modification of active sites, UPC‐60‐Cl and UPC‐60‐NH2 show the selective separation of equimolar C2H2/CO2. Therefore, reasonable regulation of organic ligands plays a significant role in guiding the structure diversification and performance improvement of MOFs. [ABSTRACT FROM AUTHOR]

Background Dextrocardia with interruption of the inferior vena cava (I-IVC) is a very rare anatomical variant. Catheter ablation of atrial fibrillation (AF) in patients with this anatomical variant is challenging for electrophysiologists. This case report presents a safe, effective, and radiation-free approach for high-power ablation of AF via a superior transseptal approach in patients with dextrocardia and I-IVC. Case summary A 57-year-old man with paroxysmal AF with dextrocardia and I-IVC with azygos continuation was referred to our hospital for radiofrequency (RF) ablation. It was evident that transseptal puncture and pulmonary vein isolation (PVI) would be impossible using an IVC approach via the femoral vein. Therefore, we decided to perform left atrium (LA) ablation via the superior vena cava approach. A phased array intracardiac echocardiography (ICE) catheter was inserted in the right femoral vein. Three-dimensional (3D) anatomical reconstruction of LA, right atrium (RA), and coronary sinus (CS) ostium were performed using ICE with azygos vein and RA imaging. Navigation-enabled electrodes were inserted into annotated CS on cardiac 3D ICE image. The left internal jugular vein was accessed using an SL1 transseptal sheath and Brockenbrough needle. Transseptal puncture was performed under ICE with an RF-assisted approach. We accomplished ablation index guided high-power pulmonary vein isolation using a bi-directional guiding sheath with visualization capabilities and a surround flow contact force-sensing catheter. No complications occurred during or after the procedure. Discussion With the application of multitude of newer technologies, we can accomplish safe, effective, and fluoroscopy-free RF ablation of AF using the superior approach in patients with complex anomaly. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to determine whether driver ablation effectively treats persistent atrial fibrillation (AF) in obese patients.Methods and Results: We randomly assigned 124 persistent AF obese patients to two groups, one undergoing conventional ablation (n = 62) and the other undergoing driver ablation (n = 62). Sixty-two non-obese patients with persistent AF undergoing driver ablation served as matched controls. Bipolar electrogram dispersion was analysed for driver mapping. Epicardial adipose tissue (EAT) volume was measured using cardiac computed tomography. Obese patients had a higher proportion of driver regions in the posterior wall (56.5% vs. 32.3%, P = 0.007). Driver complexity, measured as the average number and area of driver regions, was higher in the obese group than in the non-obese group (3.5 ± 1.0 vs. 2.9 ± 0.9, P < 0.001; 15.5% ± 4.2% vs. 9.8 ± 2.6%, P < 0.001, respectively). Left atrial EAT volume correlated better with the proportion of area of driver regions than did body mass index (BMI) and total EAT (BMI: r2 = 0.250, P < 0.001; total EAT: r2 = 0.379, P < 0.001; and left atrial EAT: r2 = 0.439, P < 0.001). The rate of AF termination was significantly higher in the driver ablation group than in the conventional ablation group (82.9% vs. 22.8%, P < 0.001). During the follow-up period of 16.9 ± 6.5 months, patients in the driver ablation group had significantly better AF-free survival (91.91% vs. 79.0%, log rank test, P = 0.026) and AF/atrial tachycardia-free survival (83.9% vs. 64.5%, log rank test, P = 0.011) than did patients in the conventional ablation group.Conclusion: Obesity is associated with increased driver complexity. Driver ablation improves long-term outcomes in obese patients with persistent AF. [ABSTRACT FROM AUTHOR]

A broadband mode (de)multiplexer [(De)MUX] is proposed and experimentally demonstrated based on a triple-waveguide coupler (TWC) with the phase-matching of a multimode access-waveguide. The tolerance to the operating wavelength and fabrication error of the proposed mode (De)MUX can be relaxed with the aid of the wider access-waveguide and the middle waveguide. The optimized mode (De)MUX is with a coupling length of 48 μm and a broad bandwidth of >122 nm with the mode crosstalk of <−15 dB. The optimized device was fabricated on a 220-nm-thick silicon-on-insulator platform and the measured results indicate that the operating bandwidth is 100 nm with the mode crosstalk lower than −14 dB. [ABSTRACT FROM AUTHOR]

In this article, we construct the Riemann solutions of the compressible Euler equations in non-isentropic modified Chaplygin gas. In order to compare the Riemann solutions of modified and pure Chaplygin gas, we extend the solvable region of the Riemann solution of the pure Chaplygin gas state and discover the formation of the δ-shock waves. By studying the limiting behavior, we find that the limit of the Riemann solutions of modified Chaplygin gas is the same as pure Chaplygin gas including the δ-shock waves. Finally, we perform some numerical simulations to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI) is identified as the myocardial necrosis due to myocardial ischemia/reperfusion (I/R) injury and remains a leading cause of mortality. C1q/TNF-related protein 13 (CTRP13) is a member of CTRP family that has been found to be involved in coronary artery disease (CAD). However, the role of CTRP13 in MI remains unclear. We aimed to explore the functional role of CTRP13 in H9c2 cells exposed to hypoxia/reoxygenation (H/R). Our results demonstrated that H/R stimulation significantly decreased the expression of CTRP13 in H9c2 cells. H/R-induced an increase in ROS production and reductions in activities of SOD and CAT were prevented by CTRP13 overexpression but were aggravated by CTRP13 silencing. Moreover, CTRP13 overexpression could reverse the inductive effect of H/R on caspase-3 activity and bax expression, as well as the inhibitory effect of H/R on bcl-2 expression in H9c2 cells. However, CTRP13 silencing presented opposite effects with CTRP13 overexpression. Furthermore, CTRP13 overexpression enhanced the H/R-stimulated the expression levels of p-AMPK and nuclear Nrf2, and Nrf2 transcriptional activity. However, inhibition of AMPK reversed the CTRP13-mediated activation of Nrf2/ARE signaling and the cardiac-protective effect in H/R-exposed H9c2 cells. Additionally, silencing of Nrf2 reversed the protective effects of CTRP13 against H/R-stimulated oxidative stress and apoptosis in H9c2 cells. Finally, recombinant CTRP13 protein attenuated myocardial I/R-induced injury in rats. Taken together, these findings indicated that CTRP13 protected H9c2 cells from H/R-stimulated oxidative stress and apoptosis via regulating the AMPK/Nrf2/ARE signaling pathway. Our results provided evidence for the therapeutic potential of CTRP13 in myocardial I/R injury. [ABSTRACT FROM AUTHOR]

Aims: Health care providers have reduced outpatient services and delayed elective cardiac surgeries during the coronavirus disease 2019 (COVID‐19) epidemic, while a large number of patients face more cardiovascular risks compared with those of the pandemic. The present study attempted to explore the management of catheter ablation in arrhythmia patients during the pandemic. Methods and results: From 1 January 2020 to 24 March 2020, a total of 269 arrhythmia patients hospitalized for catheter ablation under strict risk assessments and careful infection prevention were retrospectively analysed and considered for our analysis at our centre. Preventive measured included a 14 day quarantine, severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) nucleic acid detection, adoption of personal protection equipment, application of hand disinfectant, management of hospital visitors, and maintenance of environmental hygiene. Three patients who had fever following ablation and were finally excluded from SARS‐CoV‐2 infection, and no hospital infection occurred during the 3.1 ± 1.5 day hospitalization period. Additionally, 258/269 (95.9%) patients were free from arrhythmia after a median 133 day follow‐up (Q1, 81; Q3, 143; ending 1 June 2020), and no SARS‐CoV‐2 infections occurred at follow‐up. Conclusions: By adopting strict risk assessments and careful infection prevention measures, catheter ablation in patients with arrhythmia can be safely and effectively performed during the COVID‐19 epidemic in well‐controlled areas. [ABSTRACT FROM AUTHOR]

Two series of lanthanide-based metal–organic frameworks, namely {[Ln(BIPA-TC)0.5(DMA)2(NO3)]·DMA·H2O}n (1-Ln, Ln = Eu, Dy, Sm, Nd) and {[Ln2(BIPA-TC)1.5(DMA)3(H2O)2]·2DMA·2H2O}n (2-Ln, Ln = Eu, Dy, Sm, Nd), were successfully constructed via a solvent regulation strategy based on a π-electron rich tetra-carboxylate ligand (H4BIPA-TC). 1-Ln shows a 4-connected lvt topology with the point symbol of {42·84}, but 2-Ln displays a new 4,4,6-connected wxk1 topology with the point symbol of {43·83}4{46·66·83}2{86}. The solid-state luminescence property and the microporous nature of Eu-MOFs (1-Eu and 2-Eu) indicate that they can potentially be used as luminescent sensors. Fluorescence measurements indicate that Fe3+ exhibits the quenching effect for 1-Eu with the quenching efficiency of 93.1%. 2-Eu is the first MOF sensor for Mg2+ with the lowest detection limit of 1.53 × 10−10 mol L−1 and displays good recyclable capability. Simultaneously, in the presence of other metal ions (Ca2+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Pd2+, Al3+, Cr3+and Fe3+), 2-Eu can maintain the selective sensing of Mg2+, indicating its potential for Mg2+ turn-on sensing. [ABSTRACT FROM AUTHOR]

A ligand with a flexible conformation can be obtained by modifying functional groups. We modified H4DCBA with –CH3/–CF3 groups to construct three Zr-MOFs; the torsion of the central benzene ring changes the topologies. The three Zr-MOFs showed high adsorption rates for Cr2O72−, and the CF3-functional groups enhanced the adsorption capacity of UPC-49 for Cr2O72−. [ABSTRACT FROM AUTHOR]

A compact and nonvolatile mode-selective switch (MSS) is proposed based on a 3D triple-waveguide directional coupler integrated with a nano-heater and Ge2Sb2Se4Te1 (GSST) phase-change material. The proposed MSS is optimally designed for the quasi-TM0 and quasi-TM1 modes, with a compact length of <25 μm and mode extinction ratios (ERs) of 21.22 dB and 19.03 dB at “OFF” and “ON” states, respectively. The mode ERs are higher than 17.92 dB and 15.81 dB over a 100 nm bandwidth. A nano-heater is implemented to adjust GSST phase states, which can achieve the tuning times of 2.88 μs and 6.57 μs with the heating power of 18 mW and 62.2 mW for “ON” and “OFF” states, respectively. The absorption heating is also investigated to evaluate the thermal effect on the performance of the optimized device. The proposed MSS can be applied in photonic integration based on-chip reconfigurable mode division multiplexing networks. [ABSTRACT FROM AUTHOR]

Extrapulmonary vein focal sources have been recognized as the source of atrial fibrillation in some cases, and empiric electric isolation of the left atrial appendage has been proposed for long-standing persistent atrial fibrillation by some. Here, we present a case of redo ablation of long-standing persistent atrial fibrillation in which the left atrial appendage played a key role in maintaining AF during ablation, and atrial fibrillation was terminated by electrical isolation of the LAA. During the ablation, a rare phenomenon of half of the atria in atrial fibrillation while the other half of the atria in atrial flutter was seen. [ABSTRACT FROM AUTHOR]

An ultra-broadband mode splitter is proposed based on the phase controlling of the bridged subwavelength grating (BSWG) waveguides. An asymmetric directional coupler composed of two BSWG waveguides with an identical waveguide-width but two different bridge-widths is introduced to split the TM0 and TM1 modes based on the mode-sensitive phase-matching condition. The proposed mode splitter is optimized by utilizing the 3D full-vectorial finite difference time domain method. The results indicate that the proposed mode splitter can achieve a compact coupling length of 5.75 μm, the insertion losses of 0.41 dB and 0.53 dB, and the mode crosstalks of −19.6 dB and −27.8 dB for the TM0 and TM1 modes, respectively. The broad bandwidths of 430 nm and 372 nm can be achieved with the mode crosstalk of ≤−15 dB for the TM0 and TM1 modes, respectively. The fabrication tolerances are also studied in detail. The proposed mode splitter could be employed for signal selection and routing in the mode division multiplexing networks. [ABSTRACT FROM AUTHOR]

A switchable polarization beam splitter utilizing GST-on-silicon waveguides is introduced and comprehensively investigated in this paper. Based on the phase matching and mode hybridization, structural parameters of the presented device are optimized by using the particle swarm optimization algorithm and finite difference time domain method, so that the output fundamental transverse-electric (TE0) and transverse-magnetic (TM0) modes can be switched by controlling the phase state of GST and the device exhibits broad bandwidth, low crosstalk, and high polarization extinction ratio. For the designed device with the amorphous GST, the crosstalk is lower than −23.40 dB and the polarization extinction ratio is larger than 21.35 dB over the C-band. In the case of the crystalline GST, within the C-band, the crosstalk of less than −27.37 dB and the polarization extinction ratio of greater than 21.37 dB are achieved. [ABSTRACT FROM AUTHOR]

Background: Catheter ablation (CA) is a promising option in most patients with refractory atrial fibrillation (AF). However, data on over 5 years' outcomes with larger numbers in hypertrophic cardiomyopathy (HCM) patients with AF have not been reported. We assessed the outcome of 120 HCM patients following CA compared with a non‐CA group and general patients without AF matched by HCM type with a 61.9 ± 31.6‐month follow‐up. Methods and Results: A total of 120 patients (age 61 ± 9.8 years, female n = 43, 35.8%) with paroxysmal AF (n = 60, 50%) and persistent AF (n = 60, 50%) were enrolled. Of the 120 patients, 48 (40%) required redo procedures, and 82 (68.3%) were in sinus rhythm at the last evaluation. The composite clinical events rate following the initial CA was lower than that in the non‐CA group (P =.023) and was also comparable to that in general patients without AF matched by HCM type (P =.729). Female (HR 2.358, 95% CI, 1.151‐4.831; P =.019), NYHA functional class III‐IV (HR 2.422, 95% CI, 1.032‐5.685; P =.042) and left atrial diameter ≥50 mm (HR 3.319, 95% CI, 1.469‐7.499; P =.004) were predictors of AF recurrence after multiple procedures. Conclusions: CA was successful in restoring long‐term sinus rhythm and improving symptomatic status in most HCM patients with refractory AF especially for those patients with small atrial size and mild symptoms. In addition, CA may contribute to the prevention of major clinical adverse events in the long‐term clinical course. [ABSTRACT FROM AUTHOR]

The anode material plays a crucial role in the reliability and safety of Li-ion batteries. Among various of anode materials, Cr, Ti-based anode materials, including LiCrTiO4, Li5Cr9Ti4O24, and Li5Cr7Ti6O25, have caught much attention because of the obvious advantages, such as high potential plateau (about 1.55 V vs. Li/Li+) and minimum chance for the formation of solid electrolyte interphase film and dendritic lithium, which remarkably improves the and safety and cycling stability. Nonetheless, the poor ionic conductivity limits the large-scale applications. At present, many effective strategies have been used to enhance the electrochemical property, and several significant progresses have been also made. A comprehensive review of the recent progresses, including crystal structure, lithium storage mechanism, synthesis, modification, and morphology control, were summarized systematically. The critical challenges and future perspectives of Cr, Ti-based anode materials were highlighted. [ABSTRACT FROM AUTHOR]

We investigate optical property of polarization-maintaining fiber taper (PMFT) for tunable multi-wavelength laser generation in a fiber ring cavity. A panda-type polarization fiber is fused and tapered into a fiber taper with a diameter of about 2.5 μm. Optical and thermal properties of the PMFT are investigated theoretically and experimentally. As combined with a polarization dependent isolator, tunable multi-wavelength fiber laser operation is achieved by controlling of polarization-dependent loss in the fiber ring cavity. The laser wavelength number can be switched from 1 to 4. The 3 dB bandwidths of laser spectra are less than 0.05 nm for all wavelength numbers, with a maximum OSNR of about 54 dB. For single-wavelength laser operation near 1561.66 nm, the measured wavelength and power fluctuations are < 0.02 nm and 0.4 dB, respectively. [ABSTRACT FROM AUTHOR]

A silicon mode-selective switch (MSS) is proposed by using a horizontal metal-oxide-semiconductor (MOS) capacitor incorporated with the epsilon-near-zero (ENZ) indium-tin-oxide (ITO). The carrier concentration of the double accumulation-layers in ITO can be adjusted via the applied gate-voltage to achieve the desired switching state. The MOS-type mode of the central MOS-capacitor based triple-waveguide coupler is introduced and optimised by using the full-vectorial finite element method to switch the "OFF" and "ON" states. The thickness of the accumulation layer and the optimal design are studied by using the 3D full-vectorial eigenmode expansion method. The optimised quasi-TE0 and quasi-TE1 modes based MSSes are with the extinction ratios of 28.52 dB (19.05 dB), 37.29 dB (17.8 dB), and 37.29 dB (23.7 dB), at "OFF" ("ON") states for the accumulation-layer thicknesses of 1.5, 5.0, and 10.0 nm, respectively. The operation speed can achieve to be 6.3 GHz, 6.2 GHz, and 6.2 GHz for these three accumulation-layer thicknesses, respectively. The performance of the proposed MSS with a 2.5 V gate-voltage is also studied for preventing the oxide breakdown. The proposed MSS can be applied in the mode-division-multiplexing networks for signal switching and exchanging. [ABSTRACT FROM AUTHOR]

The finite element simulations show that non-equibiaxial residual stresses (RS) can shift the load–depth curve from the unstressed curve and cause elliptical remnant indentation in spherical indentation. Thus the relative load change between stressed and unstressed samples and the asymmetry of elliptical remnant indentation were employed as characteristic parameters to evaluate the magnitude and directionality of RS. Through theoretical and numerical analysis, the effects of RS on indentation load and remnant impression as well as the affect mechanism were systematically discussed. Finally, two equations which could provide foundations for establishing spherical indentation method to evaluate non-equibiaxial RS were obtained. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) are an emerging class of RNA species that may play a critical regulatory role in gene expression control, which can serve as diagnostic biomarkers for many diseases due to their abundant, stable, and cell- or tissue-specific expression. However, the association between circRNAs and atrial fibrillation (AF) is still not clear. In this study, we used RNA sequencing data to identify and quantify the circRNAs. Differential expression analysis of the circRNAs identified 250 up- and 126 down-regulated circRNAs in AF subjects compared with healthy donors, respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of the parental genes of the dysregulated circRNAs indicated that the up-regulated parental genes may participate in the process of DNA damage under oxidative stress. Furthermore, to annotate the dysregulated circRNAs, we constructed and merged the competing endogenous RNA (ceRNA) network and protein-protein interaction (PPI) network, respectively. In the merged network, 130 of 246 dysregulated circRNAs were successfully characterized by more than one pathway. Notably, the five circRNAs, including chr9:15474007-15490122, chr16:75445723-75448593, hsa_circ_0007256, chr12:56563313-56563992, and hsa_circ_0003533, showed the highest significance by the enrichment analysis, and four of them were enriched in cytokine-cytokine receptor interaction. These dysregulated circRNAs may mainly participate in biological processes of inflammatory response. In conclusion, the present study identified a set of dysregulated circRNAs, and characterized their potential functions, which may be associated with inflammatory responses in AF. To our knowledge, this is the first study to uncover the association between circRNAs and AF, which not only improves our understanding of the roles of circRNAs in AF, but also provides candidates of potentially functional circRNAs for AF researchers. [ABSTRACT FROM AUTHOR]

A reconfigurable mode (de)multiplexer [(De)MUX] is proposed based on a triple-silicon-waveguide directional coupler, consisting of a central waveguide with a Ge2Sb2Se4Te1 (GSST) upper layer and two outer silicon waveguides. The output mode states can be switched by the self-holding phase transition between the amorphous and crystalline states of the GSST layer, and a low loss of the proposed device can be achieved benefiting from the low propagation losses of the GSST at both states. The proposed reconfigurable mode (De)MUX is optimized by using the full-vectorial finite-element method and the thee-dimensional full-vectorial finite-difference time-domain method. The numerical results reveal that the proposed reconfigurable mode (De)MUX is with a compact length of 17.65 $\mu \text{m}$ , insertion losses of 0.16 and 0.96 dB, and mode crosstalk of −15.91 and −26.97 dB at ON and OFF states, respectively. The proposed reconfigurable mode (De)MUX can operate over the S + C + L band with high performance. The fabrication tolerances are also studied in detail. [ABSTRACT FROM AUTHOR]

A concept of power splitter with selectable splitting-ratios is proposed based on two multimode interference (MMI) sections connected by a phase-shifting region, in which phase-matching conditions can be fulfilled by using a simple angled section or alternatively using matched phase-shifters. The design example of an asymmetrical splitter (10:90) is optimized by using the transfer matrix method and 3-D full-vectorial beam propagation method. The numerical results reveal that a simple 1.2° angled section can yield a 10:90 splitter with an insertion loss of 0.74 dB and a total length of $192~\mu \text{m}$. It is also shown that, for the cascaded MMI couplers-based splitter, a more compact length of $58~\mu \text{m}$ with a lower insertion loss of 0.41 dB can be achieved. The fabrication tolerances are also investigated for the proposed asymmetrical power splitter. [ABSTRACT FROM AUTHOR]

Aluminum alloy AA 6061-T651 and 5A06-H112 rolled plates were successfully welded by friction stir welding (FSW) at three rotation speeds of 600, 900, and 1200 rpm with two transverse speeds of 100 and 150 mm/min. Mechanical properties and strain field evolution of FSW AA 6061-AA 5A06 were characterized by the uniaxial tension and digital image correlation (DIC) tests. Furthermore, the hardness distribution map of whole cross section was obtained via the nanoindentation method with 700 indents. Both DIC and nanoindentation results reveal that the heat-affected zone (HAZ) of AA 6061 alloy is the softest area in the weldment, and the fracture happens in this region. The microstructure evolution characterized by electron-backscatter diffraction (EBSD) indicates that the continuous dynamic recrystallization is the primary grain structure evolution in the stirring zone, and the grain refinement helps improve the mechanical properties. Analyses of the micro- and macrofeatures of the fracture surfaces via scanning electron microscopy (SEM) and optical microscope suggest that the increasing of heat input could enlarge the size of HAZ and reduce the slant angle of HAZ and thus lead the fracture angle to decrease and cause the dimples change from inclined ones to normal ones. [ABSTRACT FROM AUTHOR]

Aims: The superior vena cava (SVC) has been established as an important source of atrial fibrillation (AF). The role of SVC in long-standing persistent AF and the efficacy of empiric electrical isolation of the SVC are still unclear. The purpose of this study was to judge the role of SVC in catheter ablation of long-standing persistent AF.Methods and Results: A total of 102 consecutive patients with long-standing persistent AF were enrolled. All patients underwent circumferential pulmonary vein isolation, complex fractionated atrial electrograms ablation, and linear ablation during the index procedure. Superior vena cava-triggered AF and an SVC associated with the maintenance of AF were evaluated by mapping catheters during the procedure. The arrhythmogenicity of the SVC was confirmed in only 1 of the patients (0.98%). At the end of 12 months follow-up, the arrhythmia-free survival rate after a single procedure was 43.1%. After the last procedure (mean 1.47 ± 0.58 procedures), sinus rhythm was maintained in 71 (69.6%) patients, 63 of whom without antiarrhythmic drugs. The patients in AF recurrence group had higher rates of right atrium enlargement (71 vs. 34%, P = 0.03), ≥2 procedures (65 vs. 34%, P < 0.05), longer AF duration (84 ± 46 vs. 45 ± 34 months, P < 0.05), and larger left atrium diameter (50 ± 5 vs. 45 ± 6 mm, P < 0.05). In the multivariate analysis, left atrium diameter and AF duration were independent predictors of AF recurrence.Conclusion: The arrhythmogenic SVC is rarely detected in patients with long-standing persistent AF. Empiric SVC electrical isolation in the stepwise approach of long-standing persistent AF seems unnecessary. [ABSTRACT FROM AUTHOR]

Objective: To explore the cardiac electrophysiological characteristics of cardiac hypertrophy and its influence on the occurrence of ventricular tachyarrhythmias. Methods: Adult C57BL6 mice were randomly divided into a surgery group and a control group. Thoracic aortic constriction was performed on mice in the surgery group, and cardiac anatomical and ultrasonic evaluations were performed to confirm the success of the cardiac hypertrophy model 4 weeks after the operation. Using the Langendorff method of isolated heart perfusion, monophasic action potentials (MAPs) and the effective refractory period (ERP) at different parts of the heart (including the epi- and endo-myocardium of the left and right ventricles) were measured, and the induction rate of ventricular tachyarrhythmias was observed under programmed electrical stimulus (PES) and burst stimulus. Whole-cell patch-clamp was used to obtain the I-V characteristics of voltage-gated potassium channels in cardiomyocytes of different parts of the heart (including the epi- and endo-myocardium of the left and right ventricles) as well as the channels’ properties of steady-state inactivation and recovery from inactivation. Results: The ratio of heart weight to body weight and the ratio of left ventricular weight to body weight in the surgery group were significantly higher than those in the control group (P < 0.05). Ultrasonic evaluation revealed that both interventricular septal diameter (IVSD) and left ventricle posterior wall diameter (LVPWD) in the surgery group were significantly larger than those in the control group (P < 0.05). Under PES and burst stimuli, the induction rates of arrhythmias in the surgery group significantly increased, reaching 41.2% and 23.5%, respectively. Both the QT interval and action potential duration (APD) in the surgery group were significantly longer than in the control group (P<0.01), and the changes showed obvious spatial heterogeneity. Whole-cell patch-clamp recordings demonstrated that the surgery group had significantly lower potassium current densities (IPeak, Ito, IKur, Iss, and IK1) at different parts of the heart than the control group (P < 0.01), and there were significant differences in the half-inactivation voltage (V1/2) and the inactivation-recovery time constant (τ) of Ito and IKur at different parts of the heart (P < 0.01) between the surgery group and the control group. In addition, the surgery group had significantly lower densities of IPeak, Ito, and IKur in cells of the endo-myocardium (P < 0.05), and the changes showed obvious spatial heterogeneity. Conclusion: Changes in the current density and function of potassium channels contributed to irregular repolarization in cardiac hypertrophy, and the spatially heterogeneous changes of the channels may increase the occurrence of ventricular arrhythmias that accompany cardiac hypertrophy. [ABSTRACT FROM AUTHOR]

The Ca-sensitive cardiac troponin (cTn) is a hetero-trimer complex consisting of three subunits cTnC, cTnI, and cTnT, which has been recognized as an important biomarker and a potential target of cardiovascular diseases. Previously, several small-molecule agents such as levosimendan and pimobendan have been successfully developed to target this protein for the treatment of heart failure. Here, instead of small-molecule chemical drugs, we purposed rational derivation of self-inhibitory peptides as potential biologic disruptors of cTnC-cTnI interaction from the interaction complex interface. In the procedure, the crystal structure of cTn trimer was examined in detail using bioinformatics approach, from which a peptide-mediated interaction between the N-terminal domain of cTnC and the switch region of cTnI was identified. The switch is a 19-mer peptide segment Swt that contains a structured helical core capped by a short N-terminal tripeptide and a disordered C-terminal tail. Structural and energetic analysis revealed that the Swt peptide binds independently to cTnC N-terminal domain, which can be stripped from the intact cTnI subunit to interact effectively with cTnC. Further investigations found that truncation of two N-terminal residues and five C-terminal residues of the full-length Swt peptide, resulting in a shortened version namely Swt-ΔN2ΔC5 peptide, would not cause substantial loss in its binding potency to cTnC. The computational finding was then confirmed by using fluorescence-based affinity assays; the Swt and Swt-ΔN2ΔC5 peptides was experimentally measured to have a moderately high affinity to the recombinant protein of human cTnC N-terminal domain with K values at micromolar level. The Swt and Swt-ΔN2ΔC5 are considered as inhibitory peptides that can be further optimized and modified to obtain high-affinity disruptors of cTnI-cTnC interaction. [ABSTRACT FROM AUTHOR]

Objectives: Eplerenone (EPL), an antagonist of the mineralocorticoid receptor, is beneficial for atrial fibrillation and atrial fibrosis. However, the underlying mechanism remains less well known. We aimed to investigate the effect of EPL on atrial fibrosis using a mouse with selective atrial fibrosis and to explore the underlying mechanisms. Methods: EPL-treated MHC-TGFcys33ser transgenic mice that have selective atrial fibrosis (Tx+EPL mice), as well as control mice, were used for in vivo studies including histological analyses, Western blotting, and qRT-PCR studies. TGF-β1-stimulated atrial fibroblasts were treated with EPL or vehicle for the in vitro studies including Western blotting and qRT-PCR studies. In addition, Smad7 siRNA was used to knock down Smad7. Results: EPL inhibited atrial fibrosis in the Tx mice. In addition, EPL suppressed the expression of fibrosis-related molecules induced by TGF-β1 in vivo and in vitro. This occurred in concert with a downregulation of Smad7 protein expression and an upregulation of p-Smad2/3 protein expression. In addition, knockdown of Smad7 by siRNA abolished the protective roles of EPL. Conclusions: EPL inhibited atrial fibrosis in Tx mice. The underlying mechanism may involve increased protein expression of Smad7, which enhances the inhibitory feedback regulation of TGF-β1/Smad signaling. [ABSTRACT FROM AUTHOR]

A novel spot-size converter (SSC) incorporating a phase-matched polycrystalline-silicon (Poly-Si) multilayer is proposed and optimized for efficient nanophotonic coupling, which can be fabricated by using the complementary metal–oxide–semiconductor (CMOS) compatible process and can be directly integrated. An efficient algorithm, combining the rigorous \mathbfH- field-based full-vectorial finite-element method and the least square boundary residual method, is developed for the design optimization of the SSC. The use of simple single-layer and multilayer Poly-Si-based SSCs is investigated, in which the coupling process and phase matching for isolated and composite waveguides are also carried out. The coupling loss can be reduced to 2.72 dB by using an 11-Poly-Si-layer-based SSC. The on-chip integrated SSC opens up the feasibility of a low-cost passive-aligned fiber-pigtailed electronic–photonic integrated-circuit (PIC) platform. [ABSTRACT FROM PUBLISHER]

A photonic waveguide asymmetric phase-tunable Mach-Zehnder interferometer (APT-MZI) integrated by the external adjustor is presented, in which the phase can be adjusted by changing the optical path of the adjustor. Using coupled mode theory and transfer matrix method, the characteristics of the APT-MZI chip with the linear adjustor are analyzed, and their optimization designs are also given. As an example, the APT-MZI chip is fabricated using silica-on-silicon technology. The experimental results show the chip with the insertion loss of less than 5.6 dB and the extinction ratio in output spectrum of 20 dB under the free spectral range of 0.05 and 0.02 nm. The polarization-dependent wavelength shift is 0.16 nm for 100-GHz channel spacing. The proposed APT-MZI chip can provide a cost-effective and easy-to-fabricate process for optical filter having precision phase adjustment. [ABSTRACT FROM PUBLISHER]

A novel rate-dependent and self-healing conductive composite with a well-defined shear stiffening (S-ST) effect was facilely fabricated by dispersing multi-walled carbon nanotubes (MWCNTs) into a shear stiffening polymer matrix. The storage modulus (G′) of the multi-functional composite automatically increased 4 orders of magnitude when encountering external shear stimuli and the G′max was over 1 MPa, demonstrating an obvious shear stiffening effect and good safe-guarding performance. It was found that the electrical conductivity changed accordingly when shear stiffening occurred, therefore it can be applied as a force sensor during the attacking process. The rate-dependent piezoresistance effect of the composite was investigated. In quasi-static compression and high rate impact tests, different force signals can be obtained because of the negative and positive piezoresistivity effect. Self-healing tests indicated that the as-prepared composite can maintain its mechanical and electrical properties after destruction and healing treatments. Owing to the shear stiffening performance, the rate dependent conductive composite could both absorb impact energy and sense the attacking forces. Finally, a mechanism was proposed and it was believed that the glass transition induced by B–O interactions and the changes in the microstructure during the external action can be attributed to the S-ST performance and rate dependent electrical conductivity, respectively. [ABSTRACT FROM AUTHOR]