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The escalating issue of global warming, driven by the surge in CO 2 emissions, necessitates innovative strategies for reducing CO 2 emissions. A novel approach is explored in this study, where amines featuring a basic N atom with a lone pair are incorporated into cement paste to facilitate CO 2 capture from the environment. Unlike conventional applications, the focus is on the collaborative effect of various amines on CO 2 capture within diverse calcium-rich phases, encompassing portlandite and Calcium-Silicate-Hydrate (C-S-H). This investigation seeks to discern the most efficient amine and optimal concentration for CO 2 capture, particularly within distinct phases of cement paste. Notably, 2-(methylamino) ethanol (MAE) demonstrates superior performance in promoting CO₂ mineralisation and has been selected to further evaluate its ability in cement paste under natural carbonation conditions. Importantly, this research presents an exhaustive analysis of C-S-H carbonation with varying Ca/Si ratios, revealing carbonation mechanisms and consequential microstructural alterations in the presence of amine. Additionally, the presence of amine significantly influences crystal growth and the polymerisation of C-S-H. Furthermore, natural carbonation experiments underscore the efficacy of MAE, showcasing a 2.5-fold increase in calcite formation in the cement paste compared to scenarios without MAE., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have recently been a significant focus of attention because of their multiple pleiotropic effects. However, the impact of SGLT2i on atrial fibrillation (AF) remains unclear., Objectives: The goal of this study was to examine the effects of SGLT2i on AF after catheter ablation (CA)., Methods: This prospective, randomized controlled study compared the suppressive effect of SGLT2i vs dipeptidyl peptidase-4 inhibitors on AF recurrence after CA. Eighty AF patients with type 2 diabetes mellitus were randomized (by a computer-generated random sequence) to the tofogliflozin group (20 mg/d) or the anagliptin group (200 mg/d) stratified according to left atrial diameter and AF type (paroxysmal AF [PAF] or non-paroxysmal atrial fibrillation [PAF]) at screening. The primary outcome was AF recurrence at 12 months after CA., Results: Seventy patients were analyzed (mean age 70.3 ± 8.1 years; 48 male; 30 with paroxysmal AF; 38 tofogliflozin treated). Recurrent AF was detected in 24 (34.3%) of 70 patients, and the AF recurrence ratio was higher in the anagliptin group than in the tofogliflozin group (15 of 32 patients [47%] vs 9 of 38 patients [24%]; P = 0.0417). Moreover, univariate analysis revealed that compared with the nonrecurrence group (n = 46), the recurrence group (n = 24) had a higher prevalence rate of non-PAF, elevated brain natriuretic peptide, higher urinary albumin-creatinine ratio, lower rate of SGLT2i use, larger left atrial diameter, elevated E wave, lower left ventricular ejection fraction, and lower rate of cryoballoon pulmonary vein isolation., Conclusions: Compared with anagliptin, tofogliflozin achieved greater suppression of AF recurrence after CA in patients with type 2 diabetes mellitus., Competing Interests: Funding Support and Author Disclosures The authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2022 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: It remains unclear why some patients with the same heart rate during an atrial fibrillation (AF) have subjective symptoms, whereas others do not. We assessed the hypothesis that different responses of arterial and left atrial blood pressures to rapid stimulation may be associated with the symptoms of AF., Methods: A total of 110 patients who underwent catheter ablation for paroxysmal AF were retrospectively studied. Asymptomatic AF was defined as a European Heart Rhythm Association score of Ⅰ for AF-related symptoms. The left atrial pressure (LAP) was measured during sinus rhythm (SR), in 10 pacing per minute (ppm) increments from 100 ppm to the Wenckebach block rate in high right atrial pacing., Results: Asymptomatic AF was observed in 19/110 patients (17%). Patients with symptomatic AF showed higher E/e' ratio and gradual LAP increase that was dependent on the pacing rate. Patients with asymptomatic AF had decreased LAP at 100 ppm compared that at SR, and thereafter, LAP gradually increased depending on the pacing rate. The rate of LAP change compared to that at SR was significantly lower in patients with asymptomatic AF than that in patients with symptomatic AF. The rate of LAP change was independently associated with AF symptoms., Conclusion: Patients with asymptomatic AF showed lower E/e' ratio and decreased LAP at 100 ppm to rapid stimulation, followed by a steady increase in LAP afterwards. Factors other than left ventricular diastolic dysfunction may be involved in AF symptoms., (© 2022 Wiley Periodicals LLC.)

Left atrial (LA) function can help predict various cardiovascular events. Catheter ablation for atrial fibrillation (AF) modifies baseline LA function through the maintenance of sinus rhythm and myocardial injury. We investigated the impact of post-ablation LA function on recurrence of AF after ablation and identified the predictors of reduced post-ablation LA function. A total of 616 patients who underwent AF ablation (paroxysmal, N = 310; non-paroxysmal, N = 306) were retrospectively examined with cardiac computed tomography at baseline and 3 months after the final ablation procedure. Post-ablation LA emptying fraction (LAEF post ) was calculated. We evaluated the association between LAEF post and recurrence of AF after the final ablation procedure. Further, we assessed the predictors of reduced LAEF post . The recurrence rate of AF was 72.7% after the final ablation procedure [median follow-up 48 months (48.0, 48.0), total number of ablation sessions: 1.4 ± 0.7]. Multivariate analysis revealed that LAEF post was associated with the recurrence of AF (hazard ratio/10% increase: 0.62, 95% confidence interval: 0.51-0.75, P < 0.0001). LAEF post had a mild predictive power for recurrence of AF (c-statistics: 0.670, optimal cutoff: 26.36%, P < 0.0001). The recurrence-free proportion among patients with reduced LAEF post (< 26.36%, N = 100) and those with preserved LAEF post (≥ 26.36%, N = 516) was 40% and 79%, respectively (P < 0.0001). The predictors of reduced LAEF post were low pre-ablation LAEF, high pre-ablation LA volume, low body mass index (BMI), and female sex. Further, reduced LAEF post was associated with the total number of ablation sessions and extra-pulmonary vein LA ablation. In conclusion, reduced LAEF post was associated with recurrence of AF after ablation. Advanced LA remodeling, low BMI, and female sex could predict reduced LAEF post . Although additional ablation was associated with reduced LAEF post , it remains unclear whether reduced LAEF post resulted from the additional ablation. Reduced LAEF post might help stratify patients with ablation-refractory AF., (© 2021. Springer Japan KK, part of Springer Nature.)

Background: Pulmonary vein (PV) reconnection is the main cause of atrial fibrillation (AF) recurrence. This study aimed to examine the effect of first-pass PV isolation (PVI) on PV reconnection frequency during the procedure and on AF ablation outcomes., Methods: This retrospective study included 446 patients with drug-refractory AF (370 men, aged 64 ± 10 years) who underwent initial PVI using an open-irrigated contact force catheter between January 2015 and October 2016. We investigated the effect of first-pass PVI on PV reconnection during spontaneous PV reconnection and dormant conduction after an adenosine triphosphate challenge., Results: First-pass PVI was achieved in 69% (617/892) of ipsilateral PVs, of which we observed PV reconnection during the procedure in 134 (22%) PVs. This value was significantly lower than that observed in those without first-pass PVI (50%, 138/275) ( P  < .0001). We divided the subjects into two groups based on the presence or absence of first-pass PVI in at least one of two ipsilateral PVs: first-pass (n = 383, 86%) and non-first-pass groups (n = 63, 14%). The 2-year AF recurrence-free rate was significantly higher in the first-pass group than in the other group (75% vs 59%, log-rank P  = .032). In 78 patients with repeat AF ablation, the PV reconnection rate in the second procedure was significantly lower in PVs that had first-pass isolation in the first procedure (34% vs 73%, P  < .0001)., Conclusions: Absence of first-pass PVI was associated with a higher frequency of spontaneous PV reconnection and dormant conduction and poor ablation outcomes. First-pass isolation may be a useful marker for better PVI durability., Competing Interests: KI received honoraria from Johnson KK and Medtronic, Inc The other authors (YN, NT, KT, TO, YH, TO, MO, HI, KT, RN, RK, YK, AO, KI, MO, and KF) declare no conflicts of interest for this article., (© 2021 The Authors. Journal of Arrhythmia published by John Wiley & Sons Australia, Ltd on behalf of Japanese Heart Rhythm Society.)

Background: Left ventricular (LV) reverse remodeling (LVRR) after catheter ablation of atrial fibrillation (AFCA) has not been fully described. This study investigated the predictors and clinical outcomes of LVRR after AFCA in patients with LV systolic dysfunction., Methods: Of 3319 consecutive patients who underwent first-time AFCA between January 2012 and October 2019, 376 with a baseline LV ejection fraction of <50% were retrospectively evaluated. They were subjected to 256-slice multidetector computed tomography (MDCT) scanning at baseline and 3 months after AFCA. The LVRR was defined as a decrease in the LV end-systolic volume of ≥15%., Results: The prevalence of LVRR was 83% (n = 306). Multivariate logistic regression analysis including age, body mass index, diabetic status, beta-blocker use, and LV diastolic diameter revealed that the predictors of LVRR were non-paroxysmal atrial fibrillation (AF) (odds ratio, 2.68; 95% confidence interval, 1.42-5.05; p = 0.002) and absence of apparent underlying structural heart disease (4.81; 2.31-10.0; p <0.001). The prevalence of LVRR differed depending on AF recurrence pattern prior to the post-MDCT [no episode vs. paroxysmal episode (lasting <7 days) vs. persistent episode (lasting ≥7 days), 84% vs. 81% vs. 63%, respectively, p = 0.023]. During a median follow-up of 32 months, the incidence of paroxysmal form of AF recurrence was similar, whereas persistent form of AF recurrence was less frequent in patients with LVRR (10.5% vs. 18.6%, p = 0.018). Heart failure hospitalizations (2.3% vs. 15.7%, p <0.001), cardiovascular deaths (0.7% vs. 4.3%, p = 0.015), and all-cause deaths (1.3% vs. 5.7%, p = 0.018) were similarly less frequent in those with LVRR., Conclusions: LVRR after AFCA, which was predicted by non-paroxysmal AF without any apparent structural heart disease at baseline, was associated with persistent form of AF recurrence prior to the evaluation. LVRR was associated with favorable clinical outcomes., Competing Interests: Declaration of Competing Interest Koichi Inoue has received honoraria from Johnson and Johnson KK and Medtronic, Inc. Masato Okada, Nobuaki Tanaka, Takafumi Oka, Koji Tanaka, Yuichi Ninomiya, Yuko Hirao, Issei Yoshimoto, Hiroyuki Inoue, Ryo Kitagaki, Toshinari Onishi, Yasushi Koyama, Atsunori Okamura, Katsuomi Iwakura, Yasushi Sakata, and Kenshi Fujii have nothing to declare., (Copyright © 2020. Published by Elsevier Ltd.)

Many natural exposure sites have been developed to ensure the reliability of materials intended for outdoor use. However, the effects of local climate on aging have not been completely understood. This study aimed to elucidate the regional characteristics of natural aging. Non-stabilized and stabilized polycarbonates were monitored in terms of their appearance (yellowing and loss of gloss) during natural weathering at five exposure sites (Tokyo, Kagoshima, Okinawa, Florida, and Arizona) in conjunction with climate fluctuation for up to 24 months. Three approaches were employed to characterize the natural aging behaviors: (i) modeling the rate function of degradation, (ii) evaluating the contribution ratio of individual degradational factors, and (iii) estimating the "synchronicity" by cross-correlation analysis with the climate dataset. The aging rates were the highest in Arizona and lowest in Kagoshima among the five exposure sites. First, prediction curves were constructed from the degradation rate function (variables: UV irradiation, temperature, and humidity), and these curves were found to agree well with the measured aging behaviors. Second, the exposure data in Arizona demonstrated strong temperature dependence, while those in Okinawa and Florida had stronger dependence on UV irradiation compared to other sites. Lastly, the synchronicity between UV irradiation and temperature was the highest in Arizona and lowest in Kagoshima, which can explain the significantly faster deterioration in Arizona and the slow deterioration in Kagoshima.

Various methods for repairing and modifying concrete surfaces have been proposed and applied to improve the durability of existing concrete structures. Surface modification through forced carbonation is a method of densification that forms calcium carbonate in the pores on the surface of concrete to improve its durability. In this study, to evaluate the applicability of this surface modification method to existing buildings, a series of experiments was conducted in which mortar specimens were repeatedly immersed in a carbon dioxide nanobubble aqueous solution. By evaluating the weight change and absorption rate, it was determined that the higher the water/cement ratio of the mortar specimen, the higher the pore filling effect owing to immersion in the carbon dioxide nanobubble aqueous solution. In addition, the effect of clogged pores generated by the precipitation of calcium carbonate was confirmed, and it was found that the higher the water/cement ratio of the mortar specimen, the higher the pore filling effect due to clogging. We believe that our findings contribute to the development of research and construction practices associated with concrete repair and restoration.

Background: Early recurrence of atrial tachyarrhythmia (ERAT) during a 90-day blanking period (BP) often occurs after atrial fibrillation (AF) ablation. Left atrial reverse remodeling (LARR), which is the reduction in LA volume (LAV), also occurs during the BP. Both ERAT and LARR are associated with late recurrence (LR, greater than 90 days after ablation). We investigated the association between ERAT and LARR following non-paroxysmal AF (NPAF) ablation., Methods: We retrospectively reviewed 330 consecutive patients undergoing initial NPAF ablation (median follow-up: 4.0 years). Based on the timing of the final ERAT, we divided the patients into No-ERAT (N = 154, without ERAT), Early (N = 39, 0-7 days after ablation), Intermediate (N = 67, 8-30), and Late-ERAT (N = 70, 31-90) groups. We assessed the extent of LARR, defined as the percentage of decrease in LAV (%ΔLAV). The %ΔLAV cutoff value was determined by receiver operating characteristic analysis, and incorporated into a multivariate analysis to assess the association between ERAT and LARR., Results: Late - ERAT was associated with LR (hazard ratio: 6.31, 95% confidence interval (CI): 4.21-9.47, p  = 0.0001). The %ΔLAV in the Late-ERAT group was significantly smaller than the other groups ( p  < 0.0001). The predictive power of %ΔLAV for LR was slight (AUC, 0.604; best cutoff, 18.8% decrease; p  = 0.0011). In the multivariate logistic regression analysis, Late-ERAT was associated with poor LARR (%ΔLAV < 18.8% decrease) (odds ratio, 0.13; 95%CI, 0.06-0.27; p  < 0.001), whereas Early- and Intermediate-ERAT did not show any correlation., Conclusions: Late-ERAT was strongly associated with poor LARR after NPAF ablation. Both Late-ERAT and poor LARR might reflect a residual arrhythmogenic substrate causing LR., Competing Interests: K.I. has received honoraria from Bayer, Medtronic, Johnson and Johnson KK, Bristol-Myers Squibb, Daiichi-Sankyo, and Boehringer Ingelheim. K.I. has received honoraria from Boehringer Ingelheim. Other authors (T.O., Y.K., K.T., Y.H., N.T., M.O., I.Y., R.K., A.O., K. Iwakura, and K.F.) have no financial conflicts of interest to report., (© 2020 The Authors. Published by Elsevier B.V.)

Background: Associations between characteristics of premature atrial contraction (PAC) 6 months after catheter ablation (CA) and later recurrence are not known. We investigated the effects of PAC characteristics on long-term outcomes of initially successful atrial fibrillation (AF) ablation., Methods and results: In all, 378 patients (mean age 61 years, 21% female, 67% paroxysmal AF) who underwent initial radiofrequency CA for AF without recurrence up to 24-h Holter monitoring 6 months after the procedure were reviewed retrospectively. The calculated number of PAC/24 h and the length of the longest PAC run during Holter recording were analyzed. After 4.3±1.2 years (mean±SD) follow-up, 123 (32.5%) patients experienced late recurrence. Patients with recurrence had significantly more PAC/24 h (median [interquartile range] 110 [33-228] vs. 42 [16-210]; P<0.01) and a longer longest PAC run (5 [2-8] vs. 3 [1-5]; P<0.01) than those without. Receiver operating characteristic curve analysis indicated 58 PAC/24 h and a longest PAC run of 5 were optimal cut-off values for predicting recurrence. After adjusting for previously reported predictors of late recurrence, frequent PAC (≥58/24 h) and longest PAC run ≥5 were found to be independent predictors of late recurrence (hazard ratios [95% confidence intervals] 1.93 [1.24-3.02; P<0.01] and 1.81 [1.20-2.76; P<0.01], respectively)., Conclusions: Six months after successful AF ablation, both frequent PAC and long PAC run are independent predictors of late recurrence.

Background: Left atrial (LA) size is an established predictor of recurrence after catheter ablation for paroxysmal atrial fibrillation (PAF). We investigated the impact of baseline LA function on recurrence after PAF ablation and compared the predictive values of LA function with those of LA size., Methods: We retrospectively investigated 292 consecutive patients who underwent PAF ablation (median follow-up: 3.0 years). All patients had their preoperative LA volume (LAV) assessed using cardiac computed tomography under sinus rhythm. We used LA emptying fraction (LAEF) as an indicator of LA function and assessed the association between baseline LAEF and recurrence after initial ablation using a multivariate Cox hazard model. Then, we performed receiver operating characteristic analysis for predicting recurrence after single and multiple procedures and compared the c-statistics of LAEF and indexed maximum and minimum LAV (LAVI max and LAVI min ) RESULTS: In a multivariate Cox hazard model, LAEF was strongly associated with recurrence after a single procedure [hazard ratio (HR): 0.968, 95% confidence interval (CI): 0.951-0.985, p < 0.001]. In the receiver operating characteristic analysis for predicting recurrence, the predictive accuracy of LAEF was mild after a single procedure [area under the curve (AUC): 0.666, p < 0.001] and moderate after multiple procedures (AUC: 0.701, p < 0.001). The c-statistic of LAEF was significantly higher than those of LAVI max and LAVI min after a single procedure (p < 0.05, for both). After adjustment for factors related to reduced LAEF (increased serum brain natriuretic peptide, age, LA diameter, and reduced left ventricular ejection fraction), it was still associated with recurrence (HR: 0.964, 95% CI: 0.946-0.982, p < 0.001)., Conclusions: LAEF was associated with recurrence after PAF ablation. LA function is a more useful predictor than LA size., (Copyright © 2019 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)

Background: Automated ablation lesion annotation with optimal settings for parameters including contact force (CF) and catheter stability may be effective for achieving durable pulmonary vein isolation., Methods and results: We retrospectively examined 131 consecutive patients who underwent initial catheter ablation (CA) for paroxysmal atrial fibrillation (PAF) by automatic annotation system (VISITAG module)-guided radiofrequency CA (RFCA) (n=61) and 2nd-generation cryoballoon ablation (CBA) (n=70) in terms of safety and long-term efficacy. The automatic annotation criteria for the RFCA group were as follows: catheter stability range of motion ≤1.5 mm, duration ≥5 s, and CF ≥5 g. We ablated for >20 s with a force-time integral >150 gs at each site, before moving to the next site. Each interlesion distance was <6 mm. Procedural complications were more frequent in the CBA group (1.6% vs. 10.0%, P=0.034). Across a median follow-up of 2.98 years, 88.5% and 70.0% of patients in the RFCA and CBA groups, respectively, were free from recurrence (log-rank test, P=0.0039). There was also a significant difference in favor of RFCA with respect to repeat ablations (3.3% vs. 24.3%, log-rank test, P=0.0003)., Conclusions: RF ablation guided by an automated algorithm that includes CF and catheter stability parameters showed better long-term outcomes than CBA in the treatment of patients with PAF without increasing complications.

Massive volcano-related materials (VRMs) erupted from volcanoes bring the impacts to natural environment and humanity health worldwide, which include generally volcanic ash (VA), volcanic pumice (VP), volcanic tuff (VT), etc. Considering the pozzolanic activities and mechanical characters of these materials, civil engineers propose to use them in low carbon/cement and environment-friendly concrete industries as supplementary cementitious materials (SCMs) or artificial/natural aggregates. The utilization of VRMs in concretes has attracted increasing and pressing attentions from research community. Through a literature review, this paper presents comprehensively the properties of VRMs and VRM concretes (VRMCs), including the physical and chemical properties of raw VRMs and VRMCs, and the fresh, microstructural and mechanical properties of VRMCs. Besides, considering environmental impacts and the development of long-term properties, the durability and stability properties of VRMCs also are summarized in this paper. The former focuses on the resistance properties of VRMCs when subjected to aggressive environmental impacts such as chloride, sulfate, seawater, and freezing-thawing. The latter mainly includes the fatigue, creep, heat-insulating, and expansion properties of VRMCs. This study will be helpful to promote the sustainability in concrete industries, protect natural environment, and reduce the impacts of volcano disaster. Based on this review, some main conclusions are discussed and important recommendations regarding future research on the application of VRMs in concrete industries are provided.