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1.
Small ; : e2402896, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898745

RESUMEN

Developing high-performance and stable Sn-based perovskite solar cells (PSCs) is difficult due to the inherent tendency of Sn2+ oxidation and, the huge energy mismatch between perovskite and Phenyl-C61-butyric acid methyl ester (PCBM), a frequently employed electron transport layer (ETL). This study demonstrates that perovskite surface defects can be passivated and PCBM's electrical properties improved by doping n-type polymer N2200 into PCBM. The doping of PCBM with N2200 results in enhanced band alignment and improved electrical properties of PCBM. The presence of electron-donating atoms such as S, and O in N2200, effectively coordinates with free Sn2+ to prevent further oxidation. The doping of PCBM with N2200 offers a reduced conduction band offset (from 0.38 to 0.21 eV) at the interface between the ETL and perovskite. As a result, the N2200 doped PCBM-based PSCs show an enhanced open circuit voltage of 0.79 V with impressive power conversion efficiency (PCE) of 12.98% (certified PCE 11.95%). Significantly, the N2200 doped PCBM-based PSCs exhibited exceptional stability and retained above 90% of their initial PCE when subjected to continuous illumination at maximum power point tracking for 1000 h under one sun.

2.
Europace ; 26(4)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38588039

RESUMEN

AIMS: Phrenic nerve injury (PNI) is the most common complication during cryoballoon ablation. Currently, two cryoballoon systems are available, yet the difference is unclear. We sought to compare the acute procedural efficacy and safety of the two cryoballoons. METHODS: This prospective observational study consisted of 2,555 consecutive atrial fibrillation (AF) patients undergoing pulmonary vein isolation (PVI) using either conventional (Arctic Front Advance) (AFA-CB) or novel cryoballoons (POLARx) (POLARx-CB) at 19 centers between January 2022 and October 2023. RESULTS: Among 2,555 patients (68.8 ± 10.9 years, 1,740 men, paroxysmal AF[PAF] 1,670 patients), PVIs were performed by the AFA-CB and POLARx-CB in 1,358 and 1,197 patients, respectively. Touch-up ablation was required in 299(11.7%) patients. The touch-up rate was significantly lower for POLARx-CB than AFA-CB (9.5% vs. 13.6%, p = 0.002), especially for right inferior PVs (RIPVs). The touch-up rate was significantly lower for PAF than non-PAF (8.8% vs. 17.2%, P < 0.001) and was similar between the two cryoballoons in non-PAF patients. Right PNI occurred in 64(2.5%) patients and 22(0.9%) were symptomatic. It occurred during the right superior PV (RSPV) ablation in 39(1.5%) patients. The incidence was significantly higher for POLARx-CB than AFA-CB (3.8% vs. 1.3%, P < 0.001) as was the incidence of symptomatic PNI (1.7% vs. 0.1%, P < 0.001). The difference was significant during RSPV (2.5% vs. 0.7%, P < 0.001) but not RIPV ablation. The PNI recovered more quickly for the AFA-CB than POLARx-CB. CONCLUSIONS: Our study demonstrated a significantly higher incidence of right PNI and lower touch-up rate for the POLARx-CB than AFA-CB in the real-world clinical practice.


Asunto(s)
Fibrilación Atrial , Criocirugía , Traumatismos de los Nervios Periféricos , Nervio Frénico , Venas Pulmonares , Sistema de Registros , Humanos , Nervio Frénico/lesiones , Masculino , Femenino , Fibrilación Atrial/cirugía , Fibrilación Atrial/epidemiología , Venas Pulmonares/cirugía , Anciano , Criocirugía/efectos adversos , Criocirugía/métodos , Estudios Prospectivos , Incidencia , Traumatismos de los Nervios Periféricos/etiología , Traumatismos de los Nervios Periféricos/epidemiología , Traumatismos de los Nervios Periféricos/prevención & control , Persona de Mediana Edad , Resultado del Tratamiento , Ablación por Catéter/efectos adversos
3.
Nat Commun ; 15(1): 882, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287031

RESUMEN

Molecular passivation is a prominent approach for improving the performance and operation stability of halide perovskite solar cells (HPSCs). Herein, we reveal discernible effects of diammonium molecules with either an aryl or alkyl core onto Methylammonium-free perovskites. Piperazine dihydriodide (PZDI), characterized by an alkyl core-electron cloud-rich-NH terminal, proves effective in mitigating surface and bulk defects and modifying surface chemistry or interfacial energy band, ultimately leading to improved carrier extraction. Benefiting from superior PZDI passivation, the device achieves an impressive efficiency of 23.17% (area ~1 cm2) (low open circuit voltage deficit ~0.327 V) along with superior operational stability. We achieve a certified efficiency of ~21.47% (area ~1.024 cm2) for inverted HPSC. PZDI strengthens adhesion to the perovskite via -NH2I and Mulliken charge distribution. Device analysis corroborates that stronger bonding interaction attenuates the defect densities and suppresses ion migration. This work underscores the crucial role of bifunctional molecules with stronger surface adsorption in defect mitigation, setting the stage for the design of charge-regulated molecular passivation to enhance the performance and stability of HPSC.

5.
J Cardiovasc Electrophysiol ; 35(1): 198-205, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38037864

RESUMEN

INTRODUCTION: The major limitation of the current cryoballoon (CB) system is a fixed 28 mm balloon-size. We sought to analyze real-world early experience with novel-sized adjustable CB. METHODS: This multicenter observational study included 140 consecutive atrial fibrillation patients (71 years, 94 men, 86 paroxysmal) who underwent pulmonary vein (PV) isolation using expandable diameter CB capable of ablation at 28 or 31 mm. RESULTS: Out of 544 targeted PVs, 526 (96.7%) were successfully isolated by a size-adjustable CB with a 770 [690-870] second median application dose, while the remaining 18 required touch-up ablation. Among them, 326 (62.0%) PVs were isolated by a 31 mm balloon, and the rate was significantly higher for upper than lower PVs (73.0% vs. 45.7%, p < .0001) and highest for right superior (78.5%) and lowest for right inferior (39.9%) PVs. The biophysical parameters and time to isolation were comparable between the 28 and 31 mm balloons, however, the real-time PV potential monitoring capability was significantly higher for 31 mm than 28 mm balloons for the left superior PV. The esophageal temperature reached 15°C during left inferior PV ablation significantly more often with 31 mm than 28 mm balloons (43.1% vs. 18.2%, p = .008). Right phrenic nerve injury (PNI) occurred in 9 (6.4%) patients during applications (6 right superior, 2 right inferior PVs), and most occurred with a 31 mm balloon. CONCLUSIONS: Our real-world early data demonstrated high acute efficacy and safety of the novel-sized adjustable CB. The biophysical parameters were similar between the 28 and 31 mm balloons. No marked decrease in the incidence of PNI was observed even with 31 mm balloons.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Criocirugía , Venas Pulmonares , Humanos , Masculino , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Fibrilación Atrial/epidemiología , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Criocirugía/efectos adversos , Criocirugía/métodos , Venas Pulmonares/cirugía , Resultado del Tratamiento , Femenino
6.
Pacing Clin Electrophysiol ; 46(6): 475-486, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37129189

RESUMEN

BACKGROUNDS: Catheter ablation for non-paroxysmal atrial fibrillation (non-PAF) remains challenging and more effective strategy has been required to reduce postoperative arrhythmia recurrences. This study aims to investigate the efficacy and safety of a novel extensive ablation strategy for non-PAF, that is based on a combination of cryoballoon (CBA), radiofrequency (RFA), and Marshall-vein ethanol ablations (EA-VOM). METHODS: The study was a single-center, retrospective observational study. We enrolled 171 consecutive patients who underwent de-novo catheter ablation for non-PAF under conscious sedation with a novel extensive ablation strategy that included CBA for pulmonary vein isolation (PVI) and left atrial roof ablation (LARA), RFA for mitral isthmus (MI) ablation, superior vena cava isolation, and other linear ablations and EA-VOM. Recurrence of atrial arrhythmias over 1 year, procedure outcomes, and procedure-related complications were investigated. RESULTS: A total of 139 (81.3%) patients remained in sinus rhythm during 1-year follow-up. Of the 139 patients, 51 patients (29.8%) received antiarrhythmic drugs. The mean procedure time was 204 ± 45 min. PVI and LARA ablation by CBA and MI block by RFA and EA-VOM were completed in 171 (100%) and 166 (97.1%) patients, respectively. No serious procedure-related complications were observed except for one case of delayed pericardial effusion. CONCLUSION: Approximately 80% of the study patients were AF-free during 1-year follow-up period after a single procedure based on the novel extensive ablation strategy combining CBA, RFA, and EA-VOM. This strategy for non-PAF may be preferred in terms of maintenance of sinus rhythm, safety even in high-risk patients, and relatively short procedure time.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Criocirugía , Venas Pulmonares , Humanos , Etanol , Vena Cava Superior , Atrios Cardíacos , Venas Pulmonares/cirugía , Criocirugía/métodos , Ablación por Catéter/métodos , Resultado del Tratamiento , Recurrencia
7.
Card Electrophysiol Clin ; 15(1): 25-30, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36774133

RESUMEN

The left ventricular summit (LVS) is the highest point of the left ventricular epicardium, and ventricular arrhythmias originating from this area accounts for 10% to 15% of idiopathic outflow tract ventricular arrhythmias. Direct epicardial ablation of outflow tract ventricular arrhythmias arising from the LVS is successful only in a minority of patients because of close proximity to the coronary artery or thick epicardial fat. Therefore, alternative strategies should be prioritized before performing epicardial approach. When performed, electrocardiogram characteristics suggestive of the site of origin to be the accessible area within the LVS needs be evaluated to avoid ineffective epicardial approach.


Asunto(s)
Ablación por Catéter , Taquicardia Ventricular , Humanos , Electrocardiografía , Resultado del Tratamiento , Ventrículos Cardíacos/cirugía , Arritmias Cardíacas , Ablación por Catéter/efectos adversos
8.
J Interv Card Electrophysiol ; 66(4): 885-896, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35451737

RESUMEN

BACKGROUND: The FlexAbility™ SE catheter has a laser-cut 8Fr 4-mm flexible tip irrigated through laser-cut kerfs with a thermocouple 0.3 mm from the distal end. The TactiCath™ SE catheter has an 8Fr 3.5-mm tip and 6-irrigation port with a thermocouple 2.67 mm proximal to the tip. We investigated the impact of these differences on the efficacy and safety of radiofrequency (RF) applications. METHODS: RF applications at a range of powers (20 W, 30 W, and 40 W), contact forces (5 g, 15 g, and 25 g), and durations (10-60 s) using perpendicular/parallel catheter orientation were performed in excised porcine hearts. Lesion characteristics and incidence of steam pops were compared. RESULTS: A total of 540 lesions were examined. The FlexAbility™ SE catheter produced smaller lesion depths (4.0 mm vs. 4.4 mm, p = 0.014 at 20 W; 4.6 mm vs. 5.6 mm, p = 0.015 at 30 W), surface areas (22.7mm2 vs. 29.2mm2 at 20 W, p = 0.005; 23.2mm2 vs. 28.7mm2, p = 0.009 at 30 W), and volumes (126.1mm3 vs. 175.1mm3, p = 0.018 at 20 W; 183.2mm3 vs. 304.3mm3, p = 0.002 at 30 W) with perpendicular catheter placement. However, no differences were observed with parallel catheter placement. Steam-pops were significantly less frequently observed with the FlexAbility™ SE catheter (4% vs. 22%, p < 0.001) irrespective of catheter direction to the tissue. Multivariate analysis showed that use of the TactiCath™ SE catheter, power ≥ 40 W, contact force ≥ 25 g, RF duration > 30 s, parallel angle, and impedance drop ≥ 20Ω were significantly associated with occurrence of steam-pops. CONCLUSIONS: The FlexAbility™ SE catheter reduced the risk of steam-pops but produced smaller lesions with perpendicular catheter placement compared to the TactiCath™ SE catheter.


Asunto(s)
Ablación por Catéter , Vapor , Porcinos , Animales , Irrigación Terapéutica , Diseño de Equipo , Catéteres Cardíacos
10.
JACC Clin Electrophysiol ; 8(11): 1369-1377, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36424004

RESUMEN

BACKGROUND: Recent studies have found that atrial fibrillation (AF) is a risk factor for cognitive impairment. Brain hypoperfusion is hypothesized as an underlying mechanism of cognitive decline in AF patients. OBJECTIVES: This study sought to assess changes in cerebral blood flow (CBF) and brain volume after catheter ablation of AF. METHODS: Patients undergoing catheter ablation of AF were enrolled in this prospective study. AF patients being treated with pharmaceuticals alone served as a control group. Brain magnetic resonance imaging was performed before and 6 months after catheter ablation. CBF was assessed by 2-dimensional phase-contrast magnetic resonance angiography. Brain volume and bilateral hippocampal volume were measured using FreeSurfer software. RESULTS: Of the 57 study patients (age 64 ± 11 years; 45 men; paroxysmal AF: n = 22; nonparoxysmal AF: n = 35), 48 patients were freed from tachyarrhythmia recurrence beyond a 3-month blanking period. Changes in CBF and brain perfusion over 6 months were significantly greater in the study patients than control (CBF: 39.26 vs -34.86 mL; P = 0.01, ANCOVA; brain perfusion: 3.78 vs -3.02 mL/100 mL/min; P = 0.009, ANCOVA), while changes in total brain volume and bilateral hippocampal volume were similar between 2 groups (total brain volume: 2.57 vs -2.15 mL; P = 0.32, ANCOVA; bilateral hippocampal volume: 0.03 vs 0.04 mL; P = 0.8, ANCOVA). Nonparoxysmal AF at baseline was an independent predictor of an increase in CBF of >32.6 mL/min. CONCLUSIONS: Catheter ablation of AF has favorable effects on CBF, particularly in nonparoxysmal AF. Our results may partially explain the association between cognitive decline and AF.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Disfunción Cognitiva , Masculino , Humanos , Persona de Mediana Edad , Anciano , Fibrilación Atrial/diagnóstico por imagen , Fibrilación Atrial/cirugía , Estudios Prospectivos , Ablación por Catéter/efectos adversos , Circulación Cerebrovascular , Disfunción Cognitiva/etiología
12.
Pacing Clin Electrophysiol ; 45(9): 1141-1150, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35665518

RESUMEN

BACKGROUND: This study was aimed to investigate the efficacy of the over-the-wire (OTW) microelectrodes catheter in coronary venous system (CVS) mapping and treatment of outflow tract ventricular arrhythmia (OTVA) arising from the vicinity of the left ventricular summit (LVS). METHODS: Consecutive 62 patients with idiopathic OTVA in whom the OTW microelectrodes catheter was routinely used for CVS mapping were analyzed. CVS mapping was performed for both main trunk (from great cardiac vein to anterior interventricular vein) and branches including the annular branch or septal branch. RESULTS: The earliest activation site (EAS) was within the CVS in 21 patients. Among them, the EAS was within the main trunk of the CVS in seven (33%) and within the branch of the CVS in 14 (67%) patients. Radiofrequency catheter ablation was started at an anatomically adjacent site to the EAS, which eliminated OTVA in 16 (76%) patients (the endocardial LVOT in 10 and the aortic sinus of Valsalva in six patients). For the remaining five patients with unsuccessful catheter ablation at an anatomically adjacent site, targeted OTVA was eliminated by catheter ablation at the EAS within the CVS in two patients and by chemical ablation with ethanol injection in one patient, resulting in the overall success rate of 90% (19/21). CONCLUSION: The OTW microelectrodes-guided ablation of OTVA from the vicinity of the LVS was effective. In maximizing the efficacy of ablation, CVS branch mapping is important since the earliest activation was commonly recorded not in the main trunk but within the branch of the CVS.


Asunto(s)
Ablación por Catéter , Taquicardia Ventricular , Arritmias Cardíacas/cirugía , Ablación por Catéter/métodos , Catéteres , Electrocardiografía , Etanol , Ventrículos Cardíacos , Humanos , Microelectrodos , Resultado del Tratamiento
13.
J Child Lang ; : 1-21, 2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-35491939

RESUMEN

This study investigated whether Korean children follow the acquisition pattern predicted by the Aspect Hypothesis (Shirai & Andersen, 1995), and the relationship between caretakers' and children's speech. Accordingly, we analyzed a Korean corpus (Ryu-Corpus) on the CHILDES database (MacWhinney, 2000), which comprised longitudinal video-recorded interactions of three Korean children and their caregivers. Results indicate that the children used the past marker -ess principally with telic verbs, consistent with the Aspect Hypothesis. Each child's usage closely reflects the caretaker's frequency, yielding a high correlation (τb = 0.79). However, the acquisition of the imperfective marker -ko iss did not show a predicted association with activity verbs, contrary to the Aspect Hypothesis. Furthermore, caretakers' input did not correlate with the children's utterances of the imperfective marker (τb = 0.40). We argue that multiple factors such as input frequency, language-specific organization of aspectual semantics, and individual differences should be considered to explain tense-aspect acquisition.

14.
ACS Omega ; 7(14): 12147-12157, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35449936

RESUMEN

Sputtered NiO x (sp-NiO x ) is a preferred hole transporting material for perovskite solar cells because of its hole mobility, ease of manufacturability, good stability, and suitable Fermi level for hole extraction. However, uncontrolled defects in sp-NiO x can limit the efficiency of solar cells fabricated with this hole transporting layer. An interfacial layer has been proposed to modify the sp-NiO x /perovskite interface, which can contribute to improving the crystallinity of the perovskite film. Herein, a 2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid (MeO-2PACz) self-assembled monolayer was used to modify an sp-NiO x surface. We found that the MeO-2PACz interlayer improves the quality of the perovskite film due to an enlarged domain size, reduced charge recombination at the sp-NiO x /perovskite interface, and passivation of the defects in sp-NiO x surfaces. In addition, the band tail states are also reduced, as indicated by photothermal deflection spectroscopy, which thus indicates a reduction in defect levels. The overall outcome is an improvement in the device efficiency from 11.9% to 17.2% due to the modified sp-NiO x /perovskite interface, with an active area of 1 cm2 (certified efficiency of 16.25%). On the basis of these results, the interfacial engineering of the electronic properties of sp-NiO x /MeO-2PACz/perovskite is discussed in relation to the improved device performance.

15.
J Interv Card Electrophysiol ; 65(2): 419-428, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35438394

RESUMEN

PURPOSE: The size of the distal electrode and the method of measuring local impedance (LI) are different between the IntellaNav MiFi-OI™ (MiFi-OI) and IntellaNav STABLE POINT™ (SP) catheters. We investigated the impact of these differences on LI, efficacy, and safety of radiofrequency (RF) applications. METHODS: RF applications at a range of powers (30 W, 40 W, and 50 W), contact forces (10 g and 20 g), and durations (10-120 s) were performed in excised porcine hearts (N = 48). LI variation was defined by δLI-drop (= initial LI - post-RF LI) and %LI-drop (= δLI-drop/initial LI) × 100, and the relationship between lesion characteristics and LI variation was compared. RESULTS: A total of 576 lesions were examined. Although absolute δLI-drop during RF applications was significantly larger for the SP than MiFi-OI catheter (47[31-65]ohm for SP vs 37[24-51]ohm for MiFi-OI, p < 0.0001), %LI-drop was similar (23.3 [15.5-30.6]% in SP vs 24.9[17.3-32.5]% in MiFi-OI, p = 0.10). Although lesions produced by both catheters were similarly correlated with LI variation, the SP catheter produced generally larger lesions (depth; 5.0 [3.7-6.1]mm vs 4.7 [3.3-6.0]mm, p = 0.06; surface areas, 46.9 [36.8-58.8]mm2 vs 44.7 [34.3-55.5]mm2, p = 0.02; volume, 321 [165-533]mm3 vs 265[141-471]mm3, p = 0.02). Steam pops were similarly observed with both catheters. In both catheters, %LI-drop was superior to δLI-drop in correlation to lesion size (p < 0.0001) and in predicting steam pops (p < 0.01). CONCLUSIONS: Although no difference in safety profile is observed between MiFi-OI and SP catheters, the SP catheter produces larger lesions. %LI-drop is superior to δLI-drop in correlation to lesion size and in predicting steam pops as well as in normalizing the difference between catheters.


Asunto(s)
Ablación por Catéter , Vapor , Porcinos , Animales , Ablación por Catéter/métodos , Impedancia Eléctrica , Catéteres , Electrodos , Diseño de Equipo , Irrigación Terapéutica
16.
J Clin Med ; 11(3)2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-35160027

RESUMEN

BACKGROUND: Atrial anti-tachycardia pacing (A-ATP) of the right atrium (RA) has been shown to decrease the burden of atrial fibrillation (AF) in patients with dual-chamber pacemakers. The aim of this study is to identify the novel predictors of effective A-ATP for terminating AF in patients with AF undergoing catheter ablation. METHODS: This study included 41 consecutive patients undergoing a first ablation procedure for paroxysmal (PAF: n = 21) or persistent (PEF: n = 20) AF. We prospectively evaluated predictors of AF termination after A-ATP. The coefficient of variation (CoV = SD/mean × 100) of the dominant frequencies (DFs) was calculated to evaluate the variability in atrial activation. RESULTS: AF was terminated by A-ATP in 29% of PAF and 5% of PEF patients. In these patients, simultaneous high-rate pacing from the RA and the coronary sinus (CS) terminated AF in 71% of patients, in whom the mean AF cycle length (CL) before A-ATP was longer (214 ± 23 vs. 177 ± 35 ms, p = 0.02) and became slower after A-ATP (234 ± 37 vs. 176 ± 32 ms, p < 0.01), compared to unsuccessful patients. The CoV of the DFs before A-ATP were lower in both RA (6.2 ± 2.0 vs. 15.3 ± 7.9, p = 0.02) and CS (11.0 ± 7.9 vs. 24.3 ± 9.3, p < 0.01) in successful patients. CONCLUSIONS: Simultaneous biatrial A-ATP from the RA and CS could terminate AF in patients with PAF. The predictors for successful termination include longer AF CL and higher AF stability.

17.
J Interv Card Electrophysiol ; 63(2): 389-398, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34156611

RESUMEN

BACKGROUND: Although ablation energy (AE) and force-time integral (FTI) are well-known active predictors of lesion characteristics, these parameters do not reflect passive tissue reactions during ablation, which may instead be represented by drops in local impedance (LI). This study aimed to investigate if additional LI data improves predicting lesion characteristics and steam pops. METHODS: RF applications at a range of powers (30 W, 40 W, and 50 W), contact forces (8 g, 15 g, 25 g, and 35 g), and durations (10-180 s) using perpendicular/parallel catheter orientations were performed in excised porcine hearts (N = 30). The correlation between AE, FTI, and lesion characteristics was examined, and the impact of LI (%LI drop (%LID) defined by the ΔLI divided by the initial LI) was additionally assessed. RESULTS: Three hundred seventy-five lesions without steam pops were examined. Ablation energy (W × s) and FTI (g × s) showed a positive correlation with lesion depth (ρ = 0.824:P < 0.0001 and ρ = 0.708:P < 0.0001), surface area (ρ = 0.507:P < 0.0001 and ρ = 0.562:P < 0.0001), and volume (ρ = 0.807:P < 0.0001 and ρ = 0.685:P < 0.0001). %LID also showed a positive correlation individually with lesion depth (ρ = 0.643:P < 0.0001), surface area (ρ = 0.547:P < 0.0001), and volume (ρ = 0.733:P < 0.0001). However, the combined indices of AE × %LID (AE multiplied by %LID) and FTI × %LID (FTI multiplied by %LID) provided significantly stronger correlation with lesion depth (ρ = 0.834:P < 0.0001 and ρ = 0.809:P < 0.0001), surface area (ρ = 0.529:P < 0.0001 and ρ = 0.656:P < 0.0001), and volume (ρ = 0.864:P < 0.0001 and ρ = 0.838:P < 0.0001). This tendency was observed regardless of the catheter placement (parallel/perpendicular). AE (P = 0.02) and %LID (P = 0.002) independently remained as significant predictors to predict steam pops (N = 27). However, the AE × %LID did not increase the predictive power of steam pops compared to the AE alone. CONCLUSION: LI, when combined with conventional parameters (AE and FTI), may provide stronger correlation with lesion characteristics.


Asunto(s)
Ablación por Catéter , Animales , Catéteres , Impedancia Eléctrica , Humanos , Vapor , Porcinos , Irrigación Terapéutica
18.
J Interv Card Electrophysiol ; 63(1): 185-195, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33616879

RESUMEN

PURPOSE: Clinical implication of local impedance (LI) for radiofrequency (RF) ablation has not been fully established. This study aimed to investigate this point using IntellaNav MiFi OITM catheter. METHODS: LI and generator impedance drops (ΔLI and ΔGI) were evaluated in excised porcine hearts (N = 16) during RF applications at a range of powers (30 and 50 W), contact forces (5-40 g), and durations (10-180 s) using perpendicular or parallel catheter orientation. Additionally, temporal LI changes were assessed. RESULTS: Of the 240 lesions without steam pops (92.3%), ΔLI showed better correlations with lesion surface area (ρ = 0.55 vs 0.36, P = 0.004), maximum depth (ρ = 0.53 vs 0.14, P < 0.001), and lesion volume (ρ = 0.64 vs 0.23, P < 0.001) than ΔGI. Furthermore, %LI-drop (ΔLI/initial LI) demonstrated stronger correlations with lesion surface area (ρ = 0.60 vs 0.55, P < 0.001), maximum depth (ρ = 0.57 vs 0.53, P < 0.001), and volume (ρ = 0.69 vs 0.64, P < 0.001) than ΔLI. Parallel catheter orientation improved correlation of ΔLI with lesion surface area (ρ = 0.63 vs 0.40, P = 0.015) and depth (ρ = 0.68 vs 0.45, P = 0.008) and created a larger surface lesion (36.3[29.2-42.7] mm2 vs 28.8[21.6-34.2] mm2, P < 0.001) than the perpendicular. LI of the lesions significantly differed between baseline, immediately after RF, and 5 min after (P < 0.01). LI reaching plateau, larger initial LI, ΔLI, and %LI-drop, and larger RF power and longer duration were observed in pop lesions (P < 0.05). CONCLUSIONS: %LI-drop demonstrated a better correlation with lesion size than ΔLI. LI may be used as an additional parameter to predict lesion size and steam pops. Temporal variation and catheter orientation should be considered to interpret LI.


Asunto(s)
Ablación por Catéter , Animales , Catéteres , Impedancia Eléctrica , Porcinos , Irrigación Terapéutica
19.
ACS Appl Mater Interfaces ; 13(42): 50481-50490, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34644495

RESUMEN

Identification and profiling of molecular fragments generated over the lifespan of halide perovskite solar cells are needed to overcome the stability issues associated with these devices. Herein, we report the characterization of buried CH3NH3PbI3-xClx (HaP)-transport layer (TL) interfaces. By using hard X-ray photoelectron spectroscopy in conjunction with transmission electron microscopy, we reveal that the chemical decomposition of HaP is TL-dependent. With NiO1-δ, phenyl-C61-butyric acid methyl ester (PCBM), or poly(bis(4-phenyl) (2,4,6-trimethylphenyl)amine) (PTAA) as TLs, probing depth analysis shows that the degradation takes place at the interface (HaP/TL) rather than the HaP bulk area. From core-level data analysis, we identified iodine migration toward the PCBM- and PTAA-TLs. Unexpected diffusion of nitrogen inside NiO1-δ-TL was also found for the HaP/NiO1-δ sample. With a HaP/PCBM junction, HaP is dissociated to PbI2, whereas HaP/PTAA contact favored the formation of CH3I. The low stability of HaP solar cells in the PTAA-TL system is attributed to the formation of CH3I and iodide ion vacancies. Improved stability observed with NiO1-δ-TL is related to weak dissociation of stoichiometric HaP. Here, we provide a new insight to further distinguish different mechanisms of degradation to improve the long-term stability and performance of HaP solar cells.

20.
Front Psychol ; 12: 661923, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34177715

RESUMEN

Previous studies have shown that the grammatical aspect of verb predicates has an effect on tense-aspect sentence processing. However, it remains unclear as to whether the interaction of lexical aspect and grammatical aspect can influence the form-meaning association in the second language (L2) tense-aspect sentence processing, especially for the learners whose native language is grammatically marked differently from their L2. This study conducts a psycholinguistic investigation to highlight how the prototypical and non-prototypical associations predicted in the Aspect Hypothesis and L2 proficiency level influence the processing of English past tense and progressive morphology by Mandarin Chinese learners at two proficiency levels and native English speakers. The results show that the prototypical associations of English tense-aspect categories predicted in the Aspect Hypothesis, such as achievement verbs with past tense and activity verbs with the progressive aspect, can engender shorter reading time than non-prototypical associations for both native speakers and second language learners. There is no significant difference between native speakers and Chinese learners of English in their processing of prototypical items, while significant differences exist in the processing of non-prototypical items. The L2 proficiency level does not have an effect on the processing of prototypes but on the processing of non-prototypes in the L2 tense-aspect marking. This study extends previous research, showing the interaction effect of lexical aspect and grammatical aspect in the form-meaning association in L2 tense-aspect sentence processing.

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