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Nowadays, tomato, a commercially important crop, is increasingly cultivated in a soilless cultivation system to counteract climate change. Normally, this system uses cocopeat as a substrate, but its high cost and environmental impact have led to growing interest in alternatives like biochar (BC). In addition, biostimulants, such as wood distillate (WD), a pyrolysis by-product, are increasingly being used to improve fruit yield and quality. BC was used to partially replace (2% and 5%) cocopeat in growth bags for soilless tomato cultivation. Moreover, WD (3 mL/L) was distributed in the substrate every two weeks. The effect of BC and WD on tomato plant growth, fruit quality, and substrate microbial community was investigated. The integration of BC and WD into a soilless growing system for tomato cultivation can improve the fruit quality and influence the microbial activity of the substrate. Replacing part of the cocopeat in the substrate with BC and using an agri-waste-derived biostimulant represent a step forward in making agriculture more sustainable. [ABSTRACT FROM AUTHOR]

Despite advances in ablative therapies, outcomes remain less favorable for persistent atrial fibrillation often due to presence of non-pulmonary vein triggers and abnormal atrial substrates. This review highlights advances in ablation technologies and notable scientific literature on clinical outcomes associated with pursuing adjunctive ablation targets and substrate modification during persistent atrial fibrillation ablation, while also highlighting notable future directions. [ABSTRACT FROM AUTHOR]

Background: The efficacy and safety of adjunctive low‐voltage area (LVA) ablation on outcomes of catheter ablation (CA) for atrial fibrillation (AF) remains uncertain. Methods: PubMed, Embase, Cochrane Library, and ClinicalTrials.gov were searched for randomized controlled trials (RCTs) comparing CA with versus without LVA ablation for patients with AF. Risk ratios (RR) with 95% confidence intervals (CI) were pooled with a random‐effects model. Our primary endpoint was recurrence of atrial tachyarrhythmia (ATA), including AF, atrial flutter, or atrial tachycardia. We used R version 4.3.1 for all statistical analyses. Results: Our meta‐analysis included 10 RCTs encompassing 1780 patients, of whom 890 (50%) were randomized to LVA ablation. Adjunctive LVA ablation significantly reduced recurrence of ATA (RR 0.76; 95% CI 0.67−0.88; p <.01) and reduced the number of redo ablation procedures (RR 0.54; 95% CI 0.35−0.85; p <.01), as compared with conventional ablation. Among 691 (43%) patients with documented LVAs on baseline substrate mapping, adjunctive LVA ablation substantially reduced ATA recurrences (RR 0.57; 95% CI 0.38−0.86; p <.01). There was no significant difference between groups in terms of periprocedural adverse events (RR 0.78; 95% CI 0.39−1.56; p =.49). Conclusions: Adjunctive LVA ablation is an effective and safe strategy for reducing recurrences of ATA among patients who undergo CA for AF. [ABSTRACT FROM AUTHOR]

Catheter ablation (CA) has become an established treatment strategy for managing recurrent ventricular tachycardias (VTs) in patients with structural heart disease. In recent years, percutaneous mechanical circulatory support (PMCS) devices have been increasingly used intra-operatively to improve the ablation outcome. One indication would be rescue therapy for patients who develop haemodynamic deterioration during the ablation. However, more efforts are focused on identifying subjects who are at high risk of such deterioration and could benefit from the pre-emptive use of the PMCS. The third reason to use PMCS could be the inability to identify diffuse substrate, especially in non-ischaemic cardiomyopathy. This paper reviews available experiences using various types of PMCS in different clinical scenarios. Although PMCS allows mapping during VT, it does not significantly influence acute outcomes and not convincingly long-term outcomes. On the contrary, the complication rate appears to be higher in PMCS cohorts. Our data suggest that even in patients with severe left ventricular dysfunction, the substrate modification can be performed without the need for general anaesthesia and risk of haemodynamic decompensation. In end-stage heart failure associated with the electrical storm, implantation of a left ventricular assist device (or PMCS with a transition to the left ventricular assist device) might be the preferred strategy before CA. In high-risk patients who are not potential candidates for these treatment options, radiotherapy could be considered as a bail-out treatment of recurrent VTs. These approaches should be studied in prospective trials. [ABSTRACT FROM AUTHOR]

Biphasic responses are encountered at all levels in biological systems. At the cellular level, biphasic dose-responses are widely encountered in cell signaling and post-translational modification systems and represent safeguards against overactivation or overexpression of species. In this paper, we provide a unified theoretical synthesis of biphasic responses in cell signaling systems, by assessing signaling systems ranging from basic biochemical building blocks to canonical network structures to well-characterized exemplars on one hand, and examining different types of doses on the other. By using analytical and computational approaches applied to a range of systems across levels (described by broadly employed models), we reveal (i) design principles enabling the presence of biphasic responses, including in almost all instances, an explicit characterization of the parameter space (ii) structural factors which preclude the possibility of biphasic responses (iii) different combinations of the presence or absence of enzyme-biphasic and substrate-biphasic responses, representing safeguards against overactivation and overexpression, respectively (iv) the possibility of broadly robust biphasic responses (v) the complete alteration of signaling behavior in a network due to biphasic interactions between species (biphasic regulation) (vi) the propensity of different co-existing biphasic responses in the Erk signaling network. These results both individually and in totality have a number of important consequences for systems and synthetic biology.

Abstract Background The value of additional ablation beyond pulmonary vein isolation for atrial fibrillation (AF) ablation is unclear, especially for persistent AF. It is uncertain whether substrate modification with additional extensive ablation improves outcomes. We reviewed our experience to determine whether pulmonary vein isolation with additional extensive ablation (PVIEA) improves outcomes compared to pulmonary vein isolation alone (PVIA) for AF ablation. Methods Consecutive cases of patients with PVIA versus PVIEA were compared between September 9, 2013 and December 12, 2020. Procedural data collected include radiofrequency ablation delivery time (RADT) and arrhythmia inducibility. Clinical data collected include sinus rhythm maintenance post‐procedure. Results A total of 235 patients were studied (67 PVIA and 168 PVIEA). RADT was shorter when comparing ablation with PVIA versus PVIEA (32 vs. 40 min; p = .04). More arrhythmias were inducible with PVIEA (p

The author discusses a study which examined the anatomical and conduction properties of regions of late ventricular myocardial activation during intrinsic rhythm and their correspondence with induced ventricular tachycardia (VT) circuits in 36 patients using the Intellamap Orion high-resolution mapping catheter and Rhythmia Hdx mapping system. Topics include description of the scar patterns and reason that voltage mapping has fallen out of favor in parts of the electrophysiology community.

Background: Low voltage areas (LVAs) on left atrial (LA) bipolar voltage mapping correlate with areas of fibrosis. LVAs guided substrate modification was hypothesized to improve the success rate of atrial fibrillation (AF) ablation particularly in nonparoxysmal AF population. However, randomized controlled trials (RCTs) and observational studies yielded mixed results. Methods: The databases of Pubmed, EMBASE and Cochrane Central databases were searched from inception to August 2022. Relevant studies comparing LVA guided substrate modification (LVA ablation) versus conventional AF ablation (non LVA ablation) in patients with nonparoxysmal AF were identified and a meta‐analysis was performed (Graphical Abstract image). The efficacy endpoints of interest were recurrence of AF and the need for repeat ablation at 1‐year. The safety endpoint of interest was adverse events for both groups. Procedure related endpoints included total procedure time and fluoroscopy time. Results: A total of 11 studies with 1597 patients were included. A significant reduction in AF recurrence at 1‐year was observed in LVA ablation versus non LVA ablation group (risk ratio [RR] 0.63 (27% vs. 36%),95% confidence interval [CI] 0.48–0.62, p <.001]. Also, redo ablation was significantly lower in LVA ablation group (RR 0.52[18% vs. 26.7%], 95% CI 0.38–0.69, p <.00133). No difference was found in the overall adverse event (RR 0.7 [4.3% vs. 5.4%], 95% CI 0.36–1.35, p =.29). Conclusion: LVA guided substrate modification provides significant reduction in recurrence of all atrial arrhythmias at 1‐year compared with non LVA approaches in persistent and longstanding persistent AF population without increase in adverse events. [ABSTRACT FROM AUTHOR]

Aims: The optimal substrate ablation approach for post-myocardial infarction (MI) ventricular tachycardia (VT) is unknown. Proposed ablation targets are prone to individual interpretation making the ablation outcome potentially operator dependent. Evoked delayed potentials (EDPs) are a well-defined target. Evoked delayed potential ablation was effective in preventing post-MI VT recurrence in a prior study. The aims of this study were to assess long-term outcomes of EDP ablation in a large multicentre cohort of post-MI patients and to compare ablation outcomes between centres with and without prior experience in EDP ablation., Methods and Results: Patients with post-MI VT undergoing ablation in one centre performing EDP ablation since 2013 and five centres without prior experience in EDP ablation were prospectively included. A uniform mapping protocol including right ventricular extra-stimulation aiming to EDP identification was followed. Ablation endpoints were EDP elimination and VT non-inducibility. Patients were followed for VT recurrence, mortality, heart transplant, and left ventricular assist device implantation. In total, 130 patients were included. The protocol was successfully performed in 99%, and in 94%, EDPs were identified and ablated. In total, 78% of patients were rendered non-inducible. Ventricular tachycardia-free survival was 78% [95% confidence interval (CI) 71-85] and 71% (95% CI 63-80) at 6 and 12 months, respectively. No difference in VT-free survival was observed among centres with and without prior experience in EPD ablation., Conclusion: In a large multicentre prospective cohort of patients with post-MI VT, EDP ablation resulted in good long-term outcomes. Importantly, VT recurrence rates did not differ among centres with and without prior experience in EDP ablation, indicating that this approach can be easily reproduced by operators previously not familiar with the technique., Competing Interests: Conflict of interest: The Department of Cardiology Leiden received unrestricted research and fellowship grants from Edward Lifesciences, Boston Scientific, Medtronic, Biotronik, and Biosense Webster. A.O. received consulting fees from Abbott, Biosense Webster, Boston Scientific, and Medtronic. K.V. received research grants from Medtronic, Biosense Webster and Abbott, and consulting fees from Medtronic, Abbott, Biosense Webster, Philips, Boston Scientific and AstraZeneca; all paid to the Cardiovascular Research Institute of Maastricht. None of the other authors declared a conflict of interest., (© The Author(s) 2025. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Ti/AlN/Ti multilayer solar absorber coating was deposited on modified stainless-steel substrate using sputtering. The coating was exhibited high solar absorptance (0.896) and low thermal emittance (0.190) with 4.72 selectivity (α/ɛ) in the solar and infrared spectrum, respectively. Similar work using AlN/Ti/AlN/Ti/AlN stacking sequence recorded low solar absorptance (0.82) and high thermal emittance (0.27), respectively, with 3.04 selectivity (α/ɛ). The novelty of the present work is evidenced. The coating was found to be thermally stable up to 500 °C in air. However, the optical properties of the coating were found to degrade at temperature of 600 °C and hence decrease in solar absorptance (from 0.896 to 0.791) and a rise in thermal emittance (from 0.190 to 0.210) were observed. The change in the optical properties is attributed to the decrease in surface roughness which led to increased surface reflectance as probed from AFM analysis. [ABSTRACT FROM AUTHOR]

Aims: The value of additional ablation beyond pulmonary vein isolation for atrial fibrillation (AF) ablation is unclear, especially for persistent AF. The optimal target for substrate modification to improve outcomes is uncertain. We investigate the utility of low-voltage area (LVA) substrate modification in patients undergoing catheter ablation for AF.Methods and Results: This meta-analysis was reported according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Medline, Scopus and Cochrane Central Register of Controlled Trials were systematically searched to identify relevant studies. Risk of bias was assessed using the Cochrane risk of bias tool. Only randomized studies were included. AF patients who underwent catheter ablation with voltage-guided substrate modification targeting LVA (LVA group) vs. conventional ablation approaches not targeting LVA (non-LVA group) were compared. Four studies comprising 539 patients were included (36% female). Freedom from arrhythmia (FFA) in patients with persistent AF was greater in the LVA group [risk ratio (RR) 1.30; 95% confidence interval (CI) 1.03-1.64]. There was no difference in FFA in patients with paroxysmal AF between groups (RR 1.30; 95% CI 0.89-1.91). There was no difference in total procedural time (mean difference -17.54 min; 95% CI -64.37 to 29.28 min) or total ablation time (mean difference -36.17 min; 95% CI -93.69 to 21.35 min) in all included patients regardless of AF type between groups. There was no difference in periprocedural complications between groups in all included patients regardless of AF type (RR 0.93; 95% CI 0.22-3.82).Conclusion: This meta-analysis demonstrates improved FFA in persistent AF patients who underwent voltage-guided substrate modification targeting LVA. [ABSTRACT FROM AUTHOR]

This work studies the impact of the electrostatic interaction between analyte molecules and silver nanoparticles (Ag NPs) on the intensity of surface-enhanced Raman scattering (SERS). For this, we fabricated nanostructured plasmonic films by immobilization of Ag NPs on glass plates and functionalized them by a set of differently charged hydrophilic thiols (sodium 2-mercaptoethyl sulfonate, mercaptopropionic acid, 2-mercaptoethanol, 2-(dimethylamino)ethanethiol hydrochloride, and thiocholine) to vary the surface charge of the SERS substrate. We used two oppositely charged porphyrins, cationic copper(II) tetrakis(4-N-methylpyridyl) porphine (CuTMpyP4) and anionic copper(II) 5,10,15,20-tetrakis(4-sulfonatophenyl)porphine (CuTSPP4), with equal charge value and similar structure as model analytes to probe the SERS signal. Our results indicate that the SERS spectrum intensity strongly, up to complete signal disappearance, correlates with the surface charge of the substrate, which tends to be negative. Using the data obtained and our model SERS system, we analyzed the modification of the Ag surface by different reagents (lithium chloride, polyethylenimine, polyhexamethylene guanidine, and multicharged metal ions). Finally, all those surface modifications were tested using a negatively charged oligonucleotide labeled with Black Hole Quencher dye. Only the addition of copper ions into the analyte solution yielded a good SERS signal. Considering the strong interaction of copper ions with the oligonucleotide molecules, we suppose that inversion of the analyte charge played a key role in this case, instead of a change of charge of the substrate surface. Changing the charge of analytes could be a promising way to get clear SERS spectra of negatively charged molecules on Ag SERS-active supports.

Background: The value of additional ablation beyond pulmonary vein isolation for atrial fibrillation (AF) ablation is unclear, especially for persistent AF. It is uncertain whether substrate modification with additional extensive ablation improves outcomes. We reviewed our experience to determine whether pulmonary vein isolation with additional extensive ablation (PVIEA) improves outcomes compared to pulmonary vein isolation alone (PVIA) for AF ablation. Methods: Consecutive cases of patients with PVIA versus PVIEA were compared between September 9, 2013 and December 12, 2020. Procedural data collected include radiofrequency ablation delivery time (RADT) and arrhythmia inducibility. Clinical data collected include sinus rhythm maintenance post‐procedure. Results: A total of 235 patients were studied (67 PVIA and 168 PVIEA). RADT was shorter when comparing ablation with PVIA versus PVIEA (32 vs. 40 min; p =.04). More arrhythmias were inducible with PVIEA (p <.01). There was no difference in sinus rhythm maintenance by Kaplan–Meier survival analysis (log‐rank test p =.75), after 3 or 12 months between groups overall, and when stratified by AF type (paroxysmal and persistent), left atrial volume, CHA2DS2‐VASc score, left ventricular ejection fraction, or catheter ablation setting (high‐power short‐duration, standard‐power standard‐duration, temperature‐controlled non‐contact‐force). Conclusion: AF ablation with PVIA or PVIEA produces similar sinus rhythm maintenance overall and when stratified by catheter setting and AF type. PVIA reduced procedure times and less arrhythmias were inducible post‐ablation. [ABSTRACT FROM AUTHOR]

The substrate of forward osmosis (FO) thin‐film composite (TFC) membranes supports the formation of the selective layer. It can remarkably influence the structure as well as the physiochemical characteristics of the selective layer formed atop. Therefore, the improvement of TFC substrates in terms of its thickness, tortuosity and porosity can further fine tune the properties of the resultant TFC membranes. In this present study, TFC membrane comprising of polyamide selective layer and palygorskite‐chitin (PAL‐CH) containing polysulfone substrate was developed for FO desalination. The effects of PAL‐CH on the surface and structural properties of the substrate were examined. The FO desalination performance of the resultant membranes was evaluated in both active‐layer facing feed solution and active‐layer facing draw solution modes using NaCl as draw solution. In comparison with the un‐modified membrane, the TFC membrane with PAL‐CH embedded polysulfone substrate exhibited enhanced water flux and lower structural parameter. The incorporation of PAL‐CH hybrid nanomaterial resulted in improved flux of 34.39 L/m2 h1, which corresponds to improvement by 110% compared to that of pristine membranes. During the antifouling test, PAL‐CH‐S/PA membrane attained 97% water recovery while the pristine membrane attained 90% water recovery. [ABSTRACT FROM AUTHOR]

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Limited data exists about the effectiveness of the coronary sinus reducer (CSR) device in patients with angina pectoris and atrial fibrillation (AF). This case demonstrates beneficial effects of AF ablation in a patient with CSR. We report four major findings: Rhythm control has a relevant effect on angina pectoris symptoms in patients with coronary artery disease and AF. In these patients, AF ablation should be considered at an early stage. Patients with persistent angina pectoris and CSR may require sinus rhythm for an optimal effect of the device. Selected coronary sinus (CS) interventions can still be performed through the mesh of the CSR device. [ABSTRACT FROM AUTHOR]

The high reflection film of large aperture mirror is an important optical element in the optical system of large aperture space camera. In order to observe more targets and obtain more earth and space observation information higher requirements were put forward for the retro reflective film of large aperture space camera. It was necessary to have a wider working spectrum and higher reflectivity toimprove the optical performance of the substrate and to reduce the influence of space environment on the performance of the high reflection film and the stress of the film. In this paper' the achievements in the research of high reflective film for large aperture space camera mirrors at home and abroad in recent years were reviewed. The review shows that although there are stiil many difficulties in the design and manufacture of high reflection film with the deepening of research and the proposal of new methods the solutions to these diificulties have been basically found. [ABSTRACT FROM AUTHOR]

Background: The substrate for ventricular tachycardia (VT) in patients with structural heart disease is usually complex and often requires extensive ablation. As a result, the incidence of major procedure-related complications has been reported to be higher when compared to patients without structural heart disease. In this study, we present a rare complication after extensive substrate modification of scar-related VT.Case: A 65-year-old man with ischemic cardiomyopathy was referred to the electrophysiology laboratory for radiofrequency ablation of VT following repetitive implantable cardioverter defibrillator shocks within a short period. As with hemodynamic intolerance of induced VT, an approach involving extensive endocardial substrate modification to reduce the arrhythmogenicity of the scars was adopted. After the procedure, the heart function of the patient deteriorated significantly. The postprocedural ECG showed a bizarre, extremely wide surface QRS complex (360 ms), termed as homologous ventricular separation. The pronounced dyssynchrony of the ventricle was corrected by an upgrade to cardiac resynchronization therapy with defibrillation (CRT-D). As a result, the symptoms of the patient improved significantly. The width of the intrinsic QRS complex was not recovered during an 18-month follow-up.Conclusion: Homologous ventricular separation is a rare arrhythmia, manifested as two separated QRS waves. This case report demonstrates, for the first time, that homologous ventricular separation may occur after extensive substrate modification of scar-related VT. CRT-D can correct the dyssynchronous ventricle caused by homologous ventricular separation.

Background: Conduction channels have been demonstrated within the postinfarct scar and seem to be co-located with the isthmus of ventricular tachycardia (VT). Mapping the local scar potentials (SPs) that define the conduction channels is often hindered by large far-field electrograms generated by healthy myocardium.Objective: The purpose of this study was to map conduction channel using ripple mapping to categorize SPs temporally and anatomically. We tested the hypothesis that ablation of early SPs would eliminate the latest SPs without direct ablation.Methods: Ripple maps of postinfarct scar were collected using the PentaRay (Biosense Webster) during normal rhythm. Maps were reviewed in reverse, and clusters of SPs were color-coded on the geometry, by timing, into early, intermediate, late, and terminal. Ablation was delivered sequentially from clusters of early SPs, checking for loss of terminal SPs as the endpoint.Results: The protocol was performed in 11 patients. Mean mapping time was 65 ± 23 minutes, and a mean 3050 ± 1839 points was collected. SP timing ranged from 98.1 ± 60.5 ms to 214.8 ± 89.8 ms post QRS peak. Earliest SPs were present at the border, occupying 16.4% of scar, whereas latest SPs occupied 4.8% at the opposing border or core. Analysis took 15 ± 10 minutes to locate channels and identify ablation targets. It was possible to eliminate latest SPs in all patients without direct ablation (mean ablation time 16.3 ± 11.1 minutes). No VT recurrence was recorded (mean follow-up 10.1 ± 7.4 months).Conclusion: Conduction channels can be located using ripple mapping to analyze SPs. Ablation at channel entrances can eliminate the latest SPs and is associated with good medium-term results. [ABSTRACT FROM AUTHOR]

Recurrence rates of atrial fibrillation (AF) after pulmonary vein isolation (PVI) are higher in patients with a left atrial low‐voltage area (LVA) than those without. However, the efficacy of LVA guided ablation is still unknown. The purpose of this study—the Efficacy and Safety of Left Atrial Low‐voltage Area Guided Ablation for Recurrence Prevention Compared to Pulmonary Vein Isolation Alone in Patients with Persistent Atrial Fibrillation trial (SUPPRESS‐AF trial)—is to elucidate whether LVA guided ablation in addition to PVI is superior to PVI alone in patients with persistent AF. The Osaka Cardiovascular Conference will conduct a multicenter, randomized, open‐label trial aiming to examine whether LVA guided ablation in addition to PVI is superior to PVI alone in patients with persistent AF and LVAs. The primary outcome is the recurrence of AF documented by scheduled or symptom‐driven electrocardiography (ECG) during the 1 year follow‐up period after the index ablation. The key secondary endpoints include all‐cause death, symptomatic stroke, bleeding events, and other complications related to the procedure. A total of 340 patients with an LVA will be enrolled and followed up to 1 year. The SUPPRESS‐AF trial is a randomized controlled trial designed to assess whether LVA guided ablation in addition to PVI is superior to PVI alone for patients with persistent AF and LVAs detected while undergoing their first catheter ablation. [ABSTRACT FROM AUTHOR]

The article comments on a study on high-density pace-mapping for myocardial scar-related ventricular tachycardia (VT) ablation. It points out the usefulness of pace-mapping during sinus rhythm to identifying the general location of focal arrhythmia sources. it reviews the use of pace-mapping technique in measuring the correlation between VT and paced QRS morphology and suggests its application in cases in which the critical isthmus is not located on the surface of being mapped.

Catheter ablation (CA) has become an established treatment strategy for managing recurrent ventricular tachycardias (VTs) in patients with structural heart disease. In recent years, percutaneous mechanical circulatory support (PMCS) devices have been increasingly used intra-operatively to improve the ablation outcome. One indication would be rescue therapy for patients who develop haemodynamic deterioration during the ablation. However, more efforts are focused on identifying subjects who are at high risk of such deterioration and could benefit from the pre-emptive use of the PMCS. The third reason to use PMCS could be the inability to identify diffuse substrate, especially in non-ischaemic cardiomyopathy. This paper reviews available experiences using various types of PMCS in different clinical scenarios. Although PMCS allows mapping during VT, it does not significantly influence acute outcomes and not convincingly long-term outcomes. On the contrary, the complication rate appears to be higher in PMCS cohorts. Our data suggest that even in patients with severe left ventricular dysfunction, the substrate modification can be performed without the need for general anaesthesia and risk of haemodynamic decompensation. In end-stage heart failure associated with the electrical storm, implantation of a left ventricular assist device (or PMCS with a transition to the left ventricular assist device) might be the preferred strategy before CA. In high-risk patients who are not potential candidates for these treatment options, radiotherapy could be considered as a bail-out treatment of recurrent VTs. These approaches should be studied in prospective trials., Competing Interests: Conflict of interest: J.K. reports personal fees from Biosense Webster, Boston Scientific, GE Healthcare, Medtronic, and St. Jude Medical (Abbott) for participation in scientific advisory boards and has received speaker honoraria from Biosense Webster, Biotronik, Boston Scientific, Medtronic, and St. Jude Medical (Abbott). P.P. has received speaker honoraria from St Jude Medical (Abbott) and has served as a consultant for Biotronik and Boston Scientific. The remaining authors have no disclosures., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

The aim of this study was to develop an electrochemical procedure for the advanced detection of tetracycline (TC) in water using CoAl2O4 dispersed onto carbon nanofiber-epoxy composite electrode substrate, which was selected from a series of tested carbonbased electrode substrates, i.e., commercial glassy-carbon and boron-doped diamond electrodes and home-made carbon nanotubeepoxy and carbon nanofiber-epoxy composites. Carbon nanofiber-epoxy composite electrode was found the best host for CoAl2O4 modifier based on the electrocatalytic effect towards TC oxidation and detection using cyclic voltammetry (CV) technique. The electrochemical techniques applied for electrochemical detection applications were CV, differential-pulse voltammetry (DPV), square-wave voltammetry (SWV) and chronoamperometry (CA). All the tested electrochemical techniques allowed TC determination and the electroanalytical parameters varied related to the technique type. DPV operated at the step potential of 50 mV and the modulation amplitude of 200 mV allowed the lowest limit of detection of 9 nM for TC determination. The recovery test applied for real surface water spiked with known TC concentrations among the reproducibility and the repeatability showed the great potential for the advanced quantitative determination of TC in real water or in pharmaceutical formulations. [ABSTRACT FROM AUTHOR]

Purpose: Catheter ablation is less successful for non-paroxysmal atrial fibrillation (NPAF) according to numerous follow-up studies. The choice of ablation strategy for patients with NPAF remains controversial. The objective of the study was to explore the clinical efficacy of the "ICE-FIRE" ablation. Methods: Ninety NPAF patients were enrolled. Patients were randomly divided into RF (treated with circumferential pulmonary vein isolation (CPVI) and additional substrate modification by radiofrequency ablation) group and I-F (treated with CPVI by cryoablation and additional substrate modification by radiofrequency ablation) group. After CPVI and cardioversion to sinus rhythm, high-density mapping was performed. Eight-one of 90 participants restored to sinus rhythm. Seventy-four of 81 NPAF patients showed low-voltage zone. Substrates with low-voltage zone were targeted for further modification. Participants were followed at baseline, 3, 6, 9, and 12 months after the initial ablation. Results: The I-F group shared more X-ray exposure (I-F, 264.4 ± 97.4 mGy; RF, 224.9 ± 62.0 mGy; P = 0.039) and less duration of the procedure (I-F, 150.3 ± 27.5 min; RF, 174.2 ± 38.5 min; P = 0.003) compared to RF group. The freedom from atrial arrhythmia recurrence at 12 months post-ablation was similar between the RF and I-F groups (RF, 57.1%; I-F, 71.8%; P = 0.197). However, I-F group experienced lower rehospitalization rate of AF recurrence (RF, 42.9%; I-F, 20.5%; P = 0.038). Conclusions: In NPAF patients requiring substrate mapping and modification, the "ICE-FIRE" ablation demonstrated non-inferior clinical efficacy and lower rehospitalization rate of AF recurrence when compared with pure radiofrequency ablation strategy. [ABSTRACT FROM AUTHOR]

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Background: Atypical atrial flutter (AFL) is common in patients with postsurgical atrial scar, with macro‐ or microscopic channels in the scar acting as substrate for reentry. Heterogeneous atrial scarring can cause varying flutter circuits, which makes mapping and ablation challenging, and recurrences common. Aim: We hypothesize that dynamically adjusting voltage thresholds can identify heterogeneous atrial scarring, which can then be effectively homogenized to eliminate atypical AFLs. Methods: We studied consecutive patients who presented to Electrophysiology laboratory for atypical AFL ablation with history of atriotomy and included the patients with multiple, varying flutter circuits during mapping in our study. We excluded patients with stable flutter circuit that was sustained and could be localized using traditional entrainment and activation mapping strategy. In the included patients, we performed detailed high‐density voltage map of the atrium of interest. We adjusted voltage thresholds as needed to identify heterogeneity and channels in the scarred regions. A thorough scar homogenization was performed with irrigated smart‐touch ablation catheter. Re‐inducibility of tachycardia, and immediate and long‐term outcomes were studied. Results: Of five studied cases, one was female; age 66 ± 10 years. All five had prior surgical substrate. All the patients had multiple flutter morphologies, which varied as we mapped the AFL. After scar homogenization, tachycardia was not inducible in any patient. No recurrence of flutter was noted during a mean follow‐up duration of 450 ± 27 days. Conclusion: High‐density voltage mapping and homogenization of the scar can be an effective strategy in eliminating complex scar‐mediated atypical AFL with multiple circuits. [ABSTRACT FROM AUTHOR]

Aims: Circumferential pulmonary vein isolation can be effective as sole treatment for persistent atrial fibrillation. However, identifying those patients who will respond to this therapy remains a challenge. We investigated the clinical value of the sequential low-dose ibutilide test for identifying patients with persistent atrial fibrillation in whom pulmonary vein isolation is effective as sole therapy.Methods and Results: In a prospective cohort of 180 consecutive patients with persistent atrial fibrillation, intravenous low-dose (0.004 mg/kg) ibutilide was administered 3 days before ablation and after the completion of circumferential pulmonary vein isolation. In patients in whom ibutilide did not terminate atrial fibrillation pre-procedurally, but successfully terminated it intraprocedurally, no further atrial substrate modification was performed. Pre-procedural low-dose ibutilide failed to terminate the arrhythmia in all patients with persistent atrial fibrillation, while pulmonary vein isolation ± low-dose ibutilide terminated persistent atrial fibrillation in 55 (30.6%) of them (PsAF group 1). The remaining 125 (69.4%) patients underwent electrogram-based ablation (PsAF Group 2). The control group comprised 379 consecutive patients with paroxysmal atrial fibrillation who underwent pulmonary vein isolation over the same period. At 24 months follow-up, 39 (70.9%) patients in PsAF Group 1 and 276 (72.8%) patients in the control group were free from atrial tachyarrhythmias (P = NS); the arrhythmia-free rates in both groups were higher than that in PsAF group 2 (58.4%, P = 0.005).Conclusion: The sequential low-dose ibutilide test is a simple method for identifying patients with persistent atrial fibrillation in whom pulmonary vein isolation alone is an appropriate treatment strategy. [ABSTRACT FROM AUTHOR]

Mixed cellulose ester (MCE) porous substrates were first modified by using polyvinyl alcohol (PVA) solutions. Double-skinned polyamide forward osmosis (FO) membranes were fabricated by way of interfacial polymerization on PVA-modified MCE substrates. Field emission scanning electron microscopy was used to observe the morphology change of PVA-modified MCE substrates and the corresponding polyamide active layers. Fourier transform infrared was employed to detect the functional groups of the polyamide layer. Atomic force microscope (AFM) was used to probe membrane topography and surface roughness. The hydrophilicity and mechanical strength of synthesized double-skinned polyamide membranes were, respectively, evaluated by using contact angle and tensile testing experiments. When subjected to the test of FO desalination, the synthesized membrane exhibited satisfactory separation performances with enhanced mechanical strength and long-term stability. Using deionized water as the feed solution and 1 M NaCl aqueous solution as the draw solution, the water flux was 11.32 L m–2 h–1 and the reverse salt flux was as low as 0.58 g m–2 h–1. Compared with available FO membranes in the literature, the synthesized membrane with double-skinned structure should be promising for enhancement of FO performance and long-term operation capacity in practical desalination processes. [ABSTRACT FROM AUTHOR]

Background: Left atrial substrate modification targeting low voltage zones (LVZ) is an ablation strategy that—in addition to pulmonary vein (PV) isolation—tries to eliminate arrhythmogenic mechanisms harbored in such tissue. Electrophysiological findings at reablation include (a) PV reconnection, (b) reconnection over previous substrate ablation, and (c) de‐novo LVZ. Objective: To study, prevalence and contribution of these arrhythmogenic electrophysiological entities in patients with atrial fibrillation (AF) recurrences. Methods: Consecutive patients with highly symptomatic AF undergoing index and reablation were included (n = 113). In all patients' PV reconnection, reconnection over previous substrate ablation and spontaneous de‐novo LVZ were quantitatively assessed and integrated into an individual reablation strategy. Follow‐up was based on continuous device monitoring. Results: At re‐do procedure, 45 out of 113 (39.8%) patients showed PV reconnection as the only electrophysiological abnormality. Reconduction over previous lines was the only electrophysiological abnormality in 8 out of 113 (7.1%) patients. Spontaneous de‐novo LVZ was the only electrophysiological abnormality in 12 out of 113 (10.6%) patients. Combined findings of PV reconnection, line reconduction, and/or spontaneous de‐novo LVZ were seen in 40 out of 113 (35.4%) patients. No detectable electrophysiological abnormality was observed in 8 out of 113 (7.1%) patients. In univariate analysis, none of the tested electrophysiological characteristics independently predicted the outcome after re‐do. Conclusions: In patients undergoing reablation, we could show that reconduction over previous substrate ablation as well as the development of new low voltage areas are frequent findings besides classical PV reconnection—without a clear leading cause for recurrences. These findings impact reablation strategies as well as the strategic focus during index procedures. [ABSTRACT FROM AUTHOR]

Purpose: To determine the marginal leakage of Class V restorations bonded with etch-and-rinse and self-etching adhesives applied after different dentin pretreatments over a maximum storage time of 24 months. Materials and Methods: Standardized mixed Class V cavities (5 mm × 3 mm and 2 mm deep) were cut on the buccal and lingual surfaces of 180 human molars. Two self-etching adhesive systems, Adper Prompt L-Pop (3M ESPE) and Clearfil SE Bond (Kuraray), and one etch-and-rinse bonding agent (One Step, Bisco) were applied as follows: 1. according to manufacturers' instructions; 2. after 37% H3PO4 etching for 15 s; 3. after 37% H3PO4 etching for 15 s and 5% NaOCl aq application for 2 min. Teeth were stored for 24 h, 6, 12, and 24 months in saline solution at 37°C before being stained in 0.5% solution of basic fuchsine. Dye penetration was scored on a 0 to 3 ordinal scale and analyzed with the Kruskal-Wallis H test (p < 0.05), Mann-Whitney U-test (p < 0.01), and Wilcoxon paired test (p < 0.05). Results: Significant differences exist after using the tested adhesives at dentin and enamel margins. Adhesive type and substrate pretreatment had a significant effect on the long-term sealing of Class V restorations, and aging increased leakage overtime. The extent of leakage at the enamel margins was lower than that at dentin margins. One Step recorded the best results after 24 months. Conclusion: Optimal adhesion of restorative materials to enamel and dentin is hampered by a reduction in marginal seal over time. Alternative dentinal treatments (etching or collagen removal) might increase bonding efficacy, depending on the adhesive system used. [ABSTRACT FROM AUTHOR]

We have grown orthorhombic barium disilicide ( BaSi 2 ) thin-films on modified silicon (Si) substrates by a thermal evaporation method. The surface modification of Si substrate was performed by a metal-assisted chemical etching method. The effects of etching time t e on crystalline quality as well as optical and electrical properties of the BaSi 2 films were investigated. The obtained results showed that substrate modification can enhance the crystalline quality and electrical properties; reduce the light reflection; and increase the absorption of the BaSi 2 thin-films. The t e of 8 s was chosen as the optimized condition for surface modification of Si substrate. The achieved inferred short-circuit current density, Hall mobility, and minority carrier lifetime of the BaSi 2 film at t e of 8 s were 3 8 mA/cm 2 , 2 7 3 cm 2 / Vs , and 2. 3 μ s, respectively. These results confirm that the BaSi 2 thin-film evaporated on the modified Si substrate is a promising absorber for thin-film solar cell applications. [ABSTRACT FROM AUTHOR]

Background: The efficacy and safety of adjuvant substrate modification (SM; either linear ablation [LA] or complex fractionated atrial electrogram [CFAE] ablation) in addition to pulmonary vein isolation (PVI) for the treatment of symptomatic, drug-refractory atrial fibrillation (AF), have still not been clarified and need further assessment.Method: We systematically searched the PubMed, MEDLINE, and Cochrane databases for studies comparing PVI with adjunctive SM versus PVI alone for treatment of drug-refractory AF.Results: Twenty-six (26) studies including 3,409 patients (1,975 PVI + SM; 1,434 PVI alone) were included for further analysis. Atrial fibrillation/atrial tachycardia-free survival of patients with PVI + SM was comparable with that of PVI alone (relative risk [RR], 1.06; 95% confidence interval [CI], 0.98-1.14; p = 0.143). In line with this, the primary clinical outcomes were robust, irrespective of additional LA (RR, 1.07; 95% CI, 0.97-1.18; p = 0.194) or CFAE ablation (RR, 1.04; 95% CI, 0.93-1.16; p = 0.534). Adjuvant SM is associated with longer procedural time (weighted mean difference, 20.72; 95% CI, 10.25-31.20; p = 0.0) and fluoroscopy time (weighted mean difference, 6.66; 95% CI, 1.74-11.58; p = 0.000); surprisingly, it presented similar procedure-related complications as PVI alone during AF catheter ablation (RR, 1.01; 95% CI, 0.68-1.50; p = 0.946).Conclusions: Adjuvant LA or CFAE ablation do not provide incremental benefit over PVI alone. Although substrate-based ablation markedly prolonged procedural and fluoroscopic duration, there was no evidence of increased risk of procedure-related complications. [ABSTRACT FROM AUTHOR]

Introduction: Little data exists on the electrophysiological differences between sustained atrial fibrillation (sAF; >5 minutes) vs self‐terminating nonsustained AF (nsAF; <5 minutes). We sought to investigate the electrophysiological characteristics of coronary sinus (CS) activity during postpulmonary vein isolation (PVI) sAF vs nsAF. Methods and Results: We studied 142 patients post‐PVI for paroxysmal AF (PAF). In a 50‐patient subset, CS electrograms in the first 30 seconds of induced AF were analyzed manually. A custom‐made algorithm for automated electrogram annotation was derived for validation on the whole patient set. In patients with sAF post‐PVI, CS fractionated potentials were ablated. Manual analysis showed that patients with sAF exhibited higher activation pattern variability (2.1 vs 0.5 changes/sec; P <.001); fewer proximal‐to‐distal wavefronts (25 vs 61%; P <.001); fewer unidirectional wavefronts (60 vs 86%; P <.001); more pivot locations (4.3 vs 2.1; P <.001); shorter cycle lengths (190 vs 220 ms; P <.001); and shorter cumulative isoelectric segments (35 vs 44%; P =.045) compared to nsAF. These observations were confirmed on the whole study population by automated electrogram annotation and sample entropy computation (SampEn: 0.29 ± 0.15 in sAF vs 0.15 ± 0.05 in nsAF; P <.0001). The derived model predicted sAF with 78% sensitivity, 88% specificity; agreement with manual model: 88% (Cohen's kappa= 0.76). CS defragmentation resulted in AF termination or noninducibility in 49% of sAF. Conclusion: In PAF patients post‐PVI, induced sAF shows greater activation sequence variability, shorter cycle length, and higher SampEn in the CS compared to nsAF. Automated electrogram annotation confirmed these results and accurately distinguished self‐terminating nsAF episodes from sAF based on 30‐second recordings at AF onset. [ABSTRACT FROM AUTHOR]

Paper spray mass spectrometry (PSMS) is currently used in different analytical fields, but less effort has been made so far to use PSMS for highly polar compounds. Such analytes usually show poor performance in PSMS due to their high affinity for common paper substrates in addition to high matrix effects. In this study, strategies for hydrophobic modifications of commercially available paper substrates using ten different organosilanes were developed. The modified substrates were generated, characterized, and applied for PSMS analysis of polar toxins. By using the modified paper, PSMS performance of some of the toxins could be considerably increased, especially for orellanine, showing a more than 80-fold signal enhancement when substrates modified with chlorotrimethylsilane were used. For other toxins like ricinine, only small beneficial effects could be shown on PSMS performance when using modified substrates. Statistical equivalence tests showed sufficient ruggedness of the developed procedures also compared to conventional substrates. Thus, further systematic development of paper substrates modified with organosilane derivatives based on the presented study for application in PSMS should be encouraged. Image 1 • Comprehensive study using 10 different mono-/trichlorosilanes for paper modification. • Optimization of modification methods and characterization of modified substrates. • Improvements for paper spray MS performance were achieved for many polar toxins. • Equivalence tests proved robustness of paper spray MS performance using modified substrates. [ABSTRACT FROM AUTHOR]

In this study, polysulfone/wood sawdust (PSf/WSD) mixed matrix membrane (MMM) was prepared as a novel substrate layer of thin‐film composite (TFC) membrane in water desalination. The main aim was to evaluate how different amounts of WSD (0‐5 wt%) and PSf concentrations (12‐16 wt%) in the porous substrate affect the properties of the final TFC membranes in the separation of organic and inorganic compounds. Morphological and wettability studies demonstrated that the addition of small amount of WSD (less than or equal to 1 wt%) in the casting solution resulted in more porous but similar hydrophobic substrates, while high loading (greater than or equal to 2 wt%) of WSD not only changed the substrate wettability and morphology but also increased and decreased the swelling and mechanical properties of substrate layer. Therefore, PA layer formed thereon displayed extensively varying film morphology, interfacial properties, and separation performance. Based on approximately stable permeate flux (ASPF) and apparent salt rejection efficiency (ASRE), the best TFC membrane was prepared over the substrate with 12 to 14 wt% of PSf and around 0.5 to 1 wt% of WSD. Although notable improvements in permeate flux were obtained by adding a small amount of sawdust, the results clearly indicate that the salt rejection mechanism of TFC membrane was different from the glycerin rejection mechanism. Furthermore, durability results of TFC membranes showed that in continuous operation for 30 days, TFC‐14/0.5 and TFC‐14/01 have the maximum plateau levels of stable permeate flux and salt rejection among the all TFC membranes. [ABSTRACT FROM AUTHOR]

Background: Mapping and ablation of fractionated electrograms is a common treatment for scar‐based ventricular tachycardia (VT). An automated algorithm has been developed for rapid "fractionation mapping." Methods: Electroanatomic maps from 21 ablation procedures (14 scar‐based VT and seven control idiopathic VT/premature ventricular contractions with normal voltage) were retrospectively analyzed using the Ensite Precision fractionation map (fMap; Abbott Laboratories; Abbott Park, IL, USA) algorithm. For each study, voltage maps and 30 fMaps were generated using combinations of parameters: width (5, 10, 20 ms), refractory time (15, 30 ms), sensitivity (0.1, 0.2 mV), and fractionation threshold (2, 3, 5). Parameter sensitivity was assessed by overlap of fractionated areas (fArea) with successful VT ablation sites (defined by entrainment and/or pace mapping). Specificity was assessed by presence of fractionated areas in control patients. Results: Of the 30 fMap parameter sets tested, seven identified >50% of scar‐based VT ablation sites, and 26 contained <5 cm2 fractionation on control fMaps. Three combinations of fMap width/refractory/sensitivity/threshold parameters met both of the above criteria, and 20/30/0.1/2 identified the most VT ablation sites (79%) and generated 42.3 ± 28.2 cm2 of fArea on scar‐based VT maps compared with 4.9 ± 3.2 cm2 on control maps (P = .001). None of the control patients and 23% of the scar‐based VT patients had VT recurrence at mean 15 month follow‐up. Conclusion: Careful selection of signal processing parameters optimizes sensitivity and specificity of automated fractionation mapping for scar‐based VT. Real‐time use of fMap algorithms may reduce VT ablation procedure time and improve substrate modification, which may improve outcomes. [ABSTRACT FROM AUTHOR]

Purpose: Targets for substrate-based catheter ablation of scar-related ventricular tachycardia (VT) include sites with fractionated and late potentials (LPs). We hypothesized that in patients with cardiac resynchronization therapy (CRT), the pacing mode may influence the timing of abnormal electrograms (EGMs) relative to the surface QRS complex.Methods: We assessed bipolar EGM characteristics in left ventricular low bipolar voltage areas (< 1.5 mV) from 10 patients with coronary disease and a CRT device undergoing catheter ablation for VT. EGMs at 81 sites were analyzed during three different pacing modes (biventricular (BiV), right ventricular (RV)-only, and left ventricular (LV)-only) pacing.Results: Stimulus to end of local electrogram duration (Stim-to-eEGM) depended significantly on the stimulation site (BiV, LV, or RV, p = 0.032). Single-chamber pacing unmasked LPs, not present during BiV pacing, in three patients. In another three patients, a concomitant increase in stimulus to end of surface QRS duration caused by single-site pacing compensated for the increase in Stim-to-eEGM duration, thereby prohibiting LP unmasking.Conclusion: The sequence of ventricular activation, as determined by the pacing site in patients with CRT devices, has a major influence on the detection of late potentials during substrate-guided ablation. Further study is warranted to define the optimal approaches, including the rhythm, for substrate mapping, but our findings suggest that BiV pacing may be most likely to obscure detection of late potentials as compared to single-site pacing. [ABSTRACT FROM AUTHOR]

Background: The posterior wall of the left atrium (LA) is a well‐known substrate for atrial fibrillation (AF) maintenance. Isolation of the posterior wall between the pulmonary veins (box lesion) may improve ablation success. Box lesion surface area size varies depending on the individual anatomy. This retrospective study evaluates the influence of box lesion surface area as a ratio of total LA surface area (box surface ratio) on arrhythmia recurrence. Methods: Seventy consecutive patients with persistent AF (63 ± 11 years, 53 men) undergoing computed tomography (CT) imaging and ablation procedure consisting of a first box lesion were included in this study. Box lesion surface area was measured on electroanatomical maps and total LA surface area was derived from CT. Patients were followed with 24‐h electrocardiography and exercise tests at 3, 6, and 12 months after AF ablation. Arrhythmia recurrence was defined as any AF/atrial tachycardia (AT) beyond 3 months without antiarrhythmic drugs. Results: During a median follow‐up of 13 (interquartile range = 10‐17) months, 42 (60%) patients had AF/AT recurrence. Multivariate Cox proportional regression analysis showed that a larger box surface ratio protected against recurrence (hazard ratio [HR] = 0.81; 95% confidence interval [CI] = 0.690‐0.955; P = 0.012). Left atrial volume index (HR = 1.01 [0.990‐1.024, P = 0.427] and a history of mitral valve surgery (HR = 2.90; 95% CI = 0.970‐8.693; P = 0.057) were not associated with AF recurrence in multivariate analysis. Conclusion: A larger box lesion surface area as a ratio of total LA surface area is protective for AF/AT recurrence after ablation for persistent AF. [ABSTRACT FROM AUTHOR]

Purpose: The presence of inducible atrial tachyarrhythmia after pulmonary vein isolation (PVI) during radiofrequency catheter ablation (RFCA) for persistent atrial fibrillation (AF) may indicate the necessity of further substrate modification, but the optimal ablation endpoint is unknown. We sought to assess the impact of procedural termination of inducible atrial tachyarrhythmia after PVI in comparison with continued atrial tachyarrhythmia after PVI.Methods: Among patients who underwent RFCA for persistent AF, we enrolled 93 patients who were in sinus rhythm after PVI and had inducible atrial tachyarrhythmia and 157 patients with continued atrial tachyarrhythmia after PVI. The impact of acute arrhythmia termination during further substrate modification on recurrence was compared between the two groups.Results: Acute termination was achieved in 51 (54.8%) patients in the induced arrhythmia group and 61 (38.9%) in the continued arrhythmia group. During a mean 35.8 months, acute termination did not significantly reduce arrhythmia recurrence in the induced arrhythmia group (HR 0.712, 95% CI 0.400-1.266, p = 0.247), while it was associated with improved outcome in the continued arrhythmia group (HR 0.590, 95% CI 0.355-0.979, p = 0.038). Acute termination of either induced atrial tachycardia (AT) or induced AF was not associated with improved procedure outcome. Among the continued arrhythmia group, the benefit of acute termination was statistically significant in AT (HR 0.329, 95% CI 0.108-0.997, p = 0.039), but not in AF (HR 0.704, 95% CI 0.396-1.253, p = 0.233) after PVI.Conclusions: Acute termination of induced rhythm is not a reliable ablation endpoint during substrate modification in patients with inducible arrhythmia after PVI. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Easy and lower cost substrate surface modification method is proposed. • Uniform-distributed porous structure benefit for heat transfer advancement. • Dense-grooved structure is beneficial for heat transfer enhancement. • These structure benefit for lower surface wettability and small bubbles generation. Abstract A new point from modifying substrate structure of solar cells is proposed based on direct-contact phase-change immersion cooling to solve the heat dissipation problem of solar cells worked under high concentration ratios. An electric heating plate (EHP) is carefully designed to simulate the heat flux of solar cells under high concentration ratios (184.2 X). Easy and lower cost ways of electrochemical etching and mechanical drawing bench are adopted to modify substrate surface of simulated solar cells. The result of thermal measurement shows substrate, undergoing electrochemical etching for 2 h (CE-2) or mechanical drawing bench using 800 mesh (MDB-800), owns the lower wall average temperature (85.36 and 85.7 °C) and higher surface heat transfer coefficient (3008 and 2970 W/(m2 K)). SEM results reveal that CE-2 or MDB-800 has uniform-distributed porous or dense-grooved structure. These special structures show better surface wettability and provide more active nucleus sites for small bubbles generation as well as higher bubbles update frequency according to our modified surface wettability and quantitative analysis results. Our study reveals that the advanced heat transfer performance is attributed to substrate structure with uniform-distributed porous or dense-grooved of CE-2 or MDB-800. This work gives a theoretical guidance for heat transfer advancement investigation involved in surface characteristic. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the effect of substrate modification in paroxysmal atrial fibrillation (AF) patients prior to circumferential pulmonary vein isolation (CPVI). Methods: Patients without left atrial low‐voltage and/or scar areas were defined as Group A. Patients with left atrial low‐voltage and/or scar areas underwent regular CPVI (Group B) or substrate modification after CPVI (Group C). The procedural success rate and differences in the left atrial diameter (LAD) among groups were compared at 1 year postoperatively. Results: The procedural success rate in Group C was comparable to that in Group A (P > 0.05) and was significantly higher than that in Group B (P < 0.01). The LAD of patients in Groups A and C significantly decreased at 1 year postoperatively compared to that prior to the surgery (P < 0.05). However, no significant difference was noted in Group B. Conclusions: Our study demonstrated that substrate modification could contribute to the single catheter ablation surgery success rate in patients with paroxysmal AF and narrow LAD. [ABSTRACT FROM AUTHOR]

Aims: This randomized single-centre study sought to compare the efficacy and safety of pulmonary vein isolation (PVI) plus voltage-guided ablation vs. PVI with or without linear ablation depending on the type of atrial fibrillation (AF).Methods and results: Overall, 124 ablation-naive patients with paroxysmal or persistent AF were randomized to PVI with (persistent AF) or without (paroxysmal AF) additional linear ablation (control group) vs. PVI plus ablation of low-voltage areas (LVAs) irrespective of AF type. Bipolar voltage mapping was performed during stable sinus rhythm. An LVA consisted of  ≥ 3 adjacent mapping points that each had a peak-to-peak amplitude ≤0.5 mV. After a mean follow-up of 12 ± 3 months, significantly more patients in the LVA ablation group were free from atrial arrhythmia recurrence >30 s off antiarrhythmic drugs (AADs) after a single procedure (primary endpoint) compared with control group patients [40/59 (68%) vs. 25/59 (42%), log-rank P = 0.003]. Arrhythmia-free survival on or off AADs was found in 33/59 control group patients (56%) and in 41/59 LVA ablation group patients (70%) (adjusted log-rank P = 0.10). During the 7 day Holter monitoring period at 12 months, significantly more patients in the LVA ablation group were free from arrhythmia recurrence on or off AADs [45/50 (90%) vs. 33/46 (72%), P = 0.04]. No between-group differences were observed regarding procedure duration, fluoroscopy time, and major complications.Conclusion: In this single-centre study, individually tailored substrate modification guided by voltage mapping was associated with a significantly higher arrhythmia-free survival rate compared with a conventional approach applying linear ablation according to AF type. [ABSTRACT FROM AUTHOR]

Abstract The fabrication of orthorhombic barium disilicide (BaSi 2) thin-films on modified germanium (Ge) substrates by thermal evaporation method was demonstrated, in which the surface modification of Ge substrate was performed by a simple chemical etching method. The effects of etching time on crystalline quality and optical properties of the BaSi 2 films were investigated. The results revealed that the substrate modification has positive impact in improving the crystalline quality, reducing the light reflection, and increasing the absorption of the BaSi 2 thin-films. Etching time was optimized at 15 min, considering the trade-off between crystalline quality and optical properties. Minority carrier-lifetime of the evaporated film on Ge substrate achieved 3.17 μs, which is among the high value obtained for thin BaSi 2 films. Highlights • BaSi 2 thin-films are thermally-evaporated on modified Ge substrates. • Substrate modification has positive impact in improving properties of BaSi 2. • Implied short circuit current density of BaSi 2 on modified substrate is as high as 49 mA/cm2. • Excess carrier-lifetime achieves 3.17 μs, among high values obtained for thin BaSi 2. [ABSTRACT FROM AUTHOR]

Background: Ablation approaches have been described for the management of symptomatic ventricular arrhythmias in patients with Brugada syndrome, but this treatment is still considered experimental.Objective: We aimed to perform a systematic review of the current evidence on the use of catheter ablation in Brugada syndrome.Methods: MEDLINE, Embase, and Scopus were searched for articles describing the use of catheter ablation for ventricular arrhythmia management in Brugada syndrome.Results: We included 11 case series and 11 case reports including a total of 233 patients. Ablation strategies included epicardial mapping with substrate modification (n = 180; 77.3%), endocardial-only mapping with substrate modification (n = 17; 7.3%), ventricular fibrillation (VF)-triggering premature ventricular complex ablation (n = 5; 2.1%), and mixed approaches (n = 31; 13.3%). During a 2.5- to 78-month follow-up period, the success rates in preventing ventricular tachycardia or VF (VT/VF) were 96.7%, 70.6%, and 80% with epicardial, endocardial, and triggering premature ventricular complex ablation approaches, respectively. Among patients who underwent both epicardial and endocardial mapping, there was no identifiable endocardial substrate in 92.9% of cases. Elimination of type 1 Brugada-pattern electrocardiogram was attained in 98.3% and 34.8% of the epicardial and endocardial ablation groups, respectively. VT/VF occurred in 7 of 9 patients (77.8%) who had persistent or recurrent J-ST elevation and in none of the 24 patients with complete resolution during follow-up. Pharmacologic provocation augmented the abnormal area.Conclusion: Epicardial substrate modification appears to be more effective than endocardial-only approach in preventing VT/VF. Persistent or recurrent J-ST elevation appears to represent a marker of failure of ablation. Ablation seems to be an acceptable strategy for patients with Brugada syndrome and VT/VF. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Box isolation of fibrotic areas (BIFA) is a promising ablation approach for atrial fibrillation (AF) patients. However, complete isolation of fibrotic anteroseptal left atrial area, where Bachmann's bundle is blending into the left atrial myocardium, is very specific and complex. Methods and results: In 34 AF patients with anteroseptal fibrosis, circumferential BIFA was performed in addition to pulmonary vein isolation. In 8 of 34 patients, complete isolation of the fibrotic area was achieved with BIFA alone. In 26 of 34 patients, a decrease in voltage amplitude with or without conduction delay was observed after box ablation but no complete isolation. Activation mapping and characteristic unipolar potentials revealed earliest activation inside the box from one (73%), two (15%), or three (12%) remaining inputs, in the region of Bachmann's bundle insertion. Focal ablation inside the box (mean radiofrequency impulses: 1.7 ± 0.4, mean radiofrequency time: 70 ± 19 seconds) led to complete isolation of the fibrotic area in 25 of 26 patients. Overall, 97% of anteroseptal boxes were completely isolated with additional focal ablation in the study group compared to 21% in the control group with BIFA alone (33/34 vs. 7/34, P < 0.001). Time of left atrial activation decreased significantly by 25% after complete box isolation (P < 0.001). After a single procedure, 12‐month arrhythmia‐free survival was 82% with additional focal ablation compared to 71% in the control group (P = 0.2). Conclusion: Targeted and focal ablation in the region of Bachmann's bundle is a novel and feasible technique to achieve complete isolation of the left atrial anteroseptal fibrotic area. [ABSTRACT FROM AUTHOR]

The article presents the discussion on ablation of ventricular tachycardia (VT) showing to reduce VT recurrence. Topics include randomised trial of patients with ischaemic cardiomyopathy having better results with extensive substrate modification compared to conventional VT mapping and ablation; and Ripple Mapping being superior to conventional activation mapping in atrial tachycardias.