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Introduction: This study sought to elucidate the impact of vein of Marshall (VOM) chemical ablation on atrial fibrillation (AF) drivers by investigating the changes in CARTOFINDER mappings before and after VOM chemical ablation in patients with persistent AF. Methods: This study included 23 consecutive patients undergoing catheter ablation for long‐persistent AF (>18 months). VOM chemical ablation was performed following pulmonary vein isolation. CARTOFINDER and AF cycle length (AFCL) maps were created in the left atrium (LA) before and after VOM chemical ablation. The LA was divided into 8 segments, and the number of focal activation points with 6 or more repetitions was counted in each segment. Results: The number of focal activation points was largest in the LA appendage (LAA). After VOM chemical ablation, the number of focal activation points in the LA decreased significantly (37 [interquartile range, IQR: 19–55] vs. 15 [IQR: 7–21], p <.001), and median AFCL was significantly prolonged (159 [147–168] vs. 164 [150–173] ms, p <.001). In the assessment of each segment, significant decreases in focal activation points were observed in the inferior, lateral, and anterior segments and LAA. Among the focal activation points disappearing after chemical ablation, the number in the non‐ethanol‐affected area was significantly larger than that in the affected area (13 [8–25] vs. 4 [1–10], p <.001). Conclusions: VOM chemical ablation decreases AF drivers detected by CARTOFINDER. Mechanisms other than direct myocardial damage are considered to contribute the attenuation of AF drivers. [ABSTRACT FROM AUTHOR]

Introduction: Electrophysiological characteristics of epicardial connections (ECs) in atria and pulmonary veins (PVs) are unclear despite their important contributions to atrial fibrillation (AF). Unidirectional conduction associated with source‐sink mismatch can occur in ECs due to their fine fibers with abrupt changes in orientation. We detailed the prevalence and electrophysiological characteristics of unidirectional conduction in the atria and investigated its association with the clinical manifestation of AF. Methods: This study retrospectively reviewed electrophysiological studies and radiofrequency catheter ablation in 261 consecutive patients with AF. Results: Unidirectional conduction was observed during ablation encircling the PVs in eight (3.1%) patients, and all occurred in the suspected (N = 4) or definitively (N = 4) recognized ECs. These ECs included three intercaval bundles, four septopulmonary bundles, and one Marshall bundle, and were first manifested in a second procedure in 6 (75%) patients. The unidirectional property was from PV to atrium (exit conduction) in all intercaval bundles and three septopulmonary bundles, and from atrium to PV (entrance conduction) in the remaining two bundles. Intercaval bundles acted as a limb of bi‐atrial macro‐reentrant tachycardia (50%, three of the six including previous cases). Ablation of the exit outside the PVs, including the right atrium, eliminated ECs in three (38%) patients. All patients remain free from arrhythmia recurrence after a mean 13‐month follow‐up. Conclusion: A unidirectional conduction property was closely associated with the EC, as estimated by histological findings. Recognition of this fact by electrophysiologists may help to clarify mechanisms for AF and atrial tachycardia and guide the creation of efficient and safe ablation lesion sets. [ABSTRACT FROM AUTHOR]

The breeding of agriculturally useful genes from wild crop relatives must take into account recent and future climate change. In Japan, the development of early heading wheat cultivars without the use of any major gene controlling the heading date is desired to avoid overlap of the harvesting time before the rainy season. Here, we backcrossed two early heading lines of a synthetic hexaploid wheat, derived from a crossing between durum wheat and the wild wheat progenitor Aegilops tauschii, with four Japanese elite cultivars to develop early heading lines of bread wheat. In total, nine early heading lines that showed a heading date two to eight days earlier than their parental cultivars in field conditions were selected and established from the selfed progenies of the two- or three-times backcrossed populations. The whole appearance and spike shape of the selected early heading lines looked like their parental wheat cultivars. The mature grains of the selected lines had the parental cultivars' characteristics, although the grains exhibited longer and narrower shapes. RNA sequencing-based genotyping was performed to detect single nucleotide polymorphisms between the selected lines and their parental wheat cultivars, which revealed the chromosomal regions transmitted from the parental synthetic wheat to the selected lines. The introgression regions could shorten wheat heading date, and their chromosomal positions were dependent on the backcrossed wheat cultivars. Therefore, early heading synthetic hexaploid wheat is useful for fine-tuning of the heading date through introgression of Ae. tauschii chromosomal regions. [ABSTRACT FROM AUTHOR]

We carried out online choice experiments (CE) to investigate what value Japanese individuals assign to rare versus familiar species in forest ecosystem, and to determine how preference heterogeneity arises. CE attributes comprised a forestry charge as the price attribute and rare versus familiar species of animals or plants as the good to be valued. Species numbers in a 5 km-mesh forest area were evaluated without the use of species names to focus purely on responses to numerical changes. Positional effects were also tested to validate results regarding alternatives and attributes other than the price attribute. A random parameter logit model was adopted to capture preferences for species diversity. After confirming that no positional effects existed, we found that (1) rare animals were valued more highly than rare plants, (2) familiar plants were assigned a positive value, but familiar animals were not assigned significant value at the mean parameter estimate, and (3) preference heterogeneities existed for all species. The sources of preference heterogeneity were analyzed with a latent class model having principal components of environmental attitudes. The influence of such attitudes was shown to be significant and suggested that attention should be paid to belief systems rather than solely demographics. [ABSTRACT FROM AUTHOR]

This study aimed to clarify public preferences for flood control measures in Japan, willingness to pay (WTP), and the main factors involved in WTP by applying the contingent valuation method. Findings showed that most residents surveyed expected some flood control measures, and revealed a diversity of interest in river management. WTP levels for different measures ranged from a mean of ¥2,887 to ¥4,861 and from a median of ¥1,000 to ¥2,000. However, WTP for additional flood risk reduction beyond initial levels was found to be zero. This was considered to be because WTP for flood risk reduction must be determined within a multi-risk context. WTP for flood control measures may increase with per capita income, individual preparedness, and/or experience with flooding, but may decrease with distance from a river, acceptability of flood risk, and provision of environmental information. Furthermore, perception of flood risk may increase WTP, while perception of other risks may decrease it. Methods of dealing with environmental risk that were proposed in the survey may have affected WTP levels. [ABSTRACT FROM AUTHOR]

Fuel cell electric vehicle (FCEV) using hydrogen as a fuel has been regarded as an alternative to fossil fuel-based vehicles, especially in Korea and Japan, which are the only two countries producing commercial FCEVs as of 2021. This study aims to investigate the possibility of the successful adoption of FCEVs in Korea and Japan by eliciting the stated preferences of potential consumers toward various alternative fuel vehicles. We designed a discrete choice experiment employing the Best–Worst Scaling and conducted an online panel survey. Based on a mixed logit model, we determined the factors that affect consumer preferences and compared the characteristics of Korean and Japanese consumers. Further, the simulation analysis showed that FCEVs occupy a low market share in Korea and Japan due to their high purchase price, but they can occupy a fairly high market share in both countries if there is adequate support for fueling costs. • The possibility of fuel cell electric vehicle adoption in Korea and Japan is investigated. • Korean consumers are less sensitive to purchase prices than Japanese consumers. • Fuel cell electric vehicles in Korea and Japan have a low market share without support. • The effective support policies are shown to support operation costs in both countries. [ABSTRACT FROM AUTHOR]

Importance: Uninterrupted dabigatran therapy reduces stroke risk in patients with nonvalvular atrial fibrillation (NVAF) undergoing ablation and is associated with a lower bleeding risk than uninterrupted warfarin therapy. Minimally interrupted direct oral anticoagulant therapy is widely used, but data from controlled studies are insufficient., Objective: To compare the safety and efficacy of minimally interrupted dabigatran vs uninterrupted warfarin therapy in patients undergoing catheter ablation for NVAF., Design, Setting, and Participants: The ABRIDGE-J (ABlation peRIoperative DabiGatran in use Envisioning in Japan) trial is a open-label, randomized clinical trial performed in 28 Japanese treatment centers. A total of 504 patients scheduled for NVAF ablation were enrolled; 500 were randomized to the study treatments; 499 received at least 1 dose of dabigatran etexilate (n = 248) or warfarin potassium (n = 251); and 442 underwent ablation (220 in the dabigatran group and 222 in the warfarin group). Data were collected from May 1, 2014, through September 14, 2015, and analyzed from March 7, 2017, through January 28, 2019., Interventions: Appropriate dose anticoagulation was administered 4 weeks before and at least 3 months after ablation in all patients. Dabigatran therapy was interrupted before catheter ablation (holding of 1-2 doses) and resumed after ablation., Main Outcomes and Measures: Primary end points were the incidence of embolism during the perioperative period and atrial thrombus just before the ablation. The main secondary end point was the incidence of major bleeding events until 3 months after ablation., Results: Of the 442 patients who underwent ablation, 74.9% were men and the median age was 66 years (interquartile range, 59-71 years). Before ablation, 1 cerebral infarction and 1 thrombus in the left atrium occurred in the warfarin group, but no events occurred in the interrupted dabigatran group. After ablation, the mean (SD) incidence of major bleeding events was significantly lower with dabigatran (3 patients [1.4% {0.8%}; 95% CI, 0.4%-4.2%]) vs warfarin (11 patients [5.0% {1.5%}; 95% CI, 2.8%-8.8%]; P = .03). No thromboembolic events occurred after ablation in the dabigatran group; 1 (0.5%) occurred in the warfarin group., Conclusions and Relevance: In patients undergoing ablation for NVAF, anticoagulation with minimally interrupted dabigatran therapy did not increase thromboembolic events and was associated with fewer bleeding complications than uninterrupted warfarin therapy., Trial Registration: umin.ac.jp Identifier: UMIN000013129.

Background: Recent evidence has linked early repolarization (ER) to idiopathic ventricular fibrillation (VF) in patients without structural heart disease. However, no studies have clarified whether or not there is an association between ER and the VF occurrences after the onset of an acute myocardial infarction (AMI)., Methods and Results: This study retrospectively included 220 consecutive patients with an AMI (57 female; mean age, 69±11 years) in whom the 12-lead ECGs before the AMI onset could be evaluated. The patients were classified on the basis of a VF occurrence within 48 hours after the AMI onset. Early repolarization was defined as an elevation of the QRS-ST junction of >0.1 mV from baseline in at least 2 inferior or lateral leads, manifested as QRS slurring or notching. Twenty-one (10%) patients had a VF occurrence within 48 hours of the AMI onset. A multivariate analysis revealed that ER (odds ratio [OR], 7.31; 95% confidence interval [CI], 2.21-24.14; P<0.01), a time from the onset to admission of <180 minutes (OR, 3.77; 95% CI, 1.13-12.59; P<0.05), and a Killip class greater than I (OR, 13.60; 95% CI, 3.43-53.99; P<0.001) were independent predictors of VF occurrences. As features of the ER pattern, a J-point elevation in the inferior leads, greater magnitude of the J-point elevation, notched morphology of the ER, and ER with a horizontal/descending ST segment, all were significantly associated with a VF occurrence., Conclusions: The presence of ER increased the risk of VF occurrences within 48 hours after the AMI onset.

Background: Differences in electrical properties between left and right atria (LA and RA) after pulmonary vein isolation (PVI) for atrial fibrillation (AF) are currently poorly understood. Magnetocardiograms were used to investigate the effect of PVI on bi-atrial magnetic field changes and their relationship to clinical outcomes., Methods and Results: This study included 71 patients undergoing PVI for paroxysmal AF. Magnetocardiograms were recorded at baseline and 1 day, 8 weeks, and 24 weeks after ablation. Peak magnitude of LA and RA segments on P waves was separately compared before and after PVI. During a 16-month post-ablation period, 53 (75%) patients were free from AF recurrences. LA magnetic strength in patients without recurrence persistently decreased for 24 weeks and was significantly lower at 8 weeks than that in patients with recurrence (1.28±0.69 vs. 1.74±0.71 pico-Tesla, P=0.02). RA magnetic strength in patients with recurrence persistently rose for 24 weeks and was significantly higher at 8 weeks than that in patients without recurrence (2.17±0.82 vs. 3.00±1.12 pico-Tesla, P=0.001). Multivariate analysis showed RA magnetic strength at 8 weeks to be the strongest predictor of AF recurrence (odds ratio=3.335; 95% confidence interval=1.181-9.416; P=0.02)., Conclusions: PVI resulted in distinct changes in magnetic strength in both the LA and the RA. A persistent rise in RA magnetic strength might be a robust predictor of AF recurrence after ablation.

Objective: To evaluate the burden on families with a family member suffering traumatic brain injury sequelae in Japan., Design: Cross-sectional study., Methods: Family members' burden from the sequelae of traumatic brain injury was estimated by use of willingness-to-pay models and the contingent valuation method. A national survey among 1707 members of the Japan Traumatic Brain Injury Association was conducted by postal questionnaire with open-ended questions. A total of 509 (29.8%) of the family members responded (405 men and 104 women). Mean age of patients with traumatic brain injury was 33.4 (SD 14.3) years and of responding family members 53.3 (SD 14.5) years., Results: Willingness-to-pay for the family member's recovery from sequelae of traumatic brain injury (8,694,502 Japanese yen; 79,134 US dollars/year) was similar to that reported for a family member's survival from incurable terminal disease (8,342,953 Japanese yen; 75,934 US dollars/year)., Conclusion: The data indicate that family members perceive the burden of a family member with traumatic brain injury sequelae as similar to what would have been caused by an incurable terminal disease.