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Increasing warming, atmospheric CO 2 and drought are expected to change the water dynamics of terrestrial ecosystems. Yet, limited knowledge exists about how the interactive effects of these factors will affect grassland water uptake, and whether adaptations in fine root production and traits will alter water uptake capacity. In a managed C 3 grassland, we tested the individual and combined effects of warming (+3°C), elevated CO 2 (eCO 2 ; +300 ppm) and drought on root water uptake (RWU) as well as on fine root production, trait adaptation, and fine root-to-shoot production ratios, and their relationships with RWU capacity. High temperatures, amplified by warming, exacerbated RWU reductions under drought, with negligible water-sparing effects from eCO 2 . Drought, both under current and future (warming, eCO 2 ) climatic conditions, shifted RWU towards deeper soil layers. Overall, RWU capacity related positively to fine root production and specific root length (SRL), and negatively to mean root diameters. Warming effects on traits (reduced SRL, increased diameter) and the ratio of fine root-to-shoot production (increased) were offset by eCO 2 . We conclude that under warmer future conditions, irrespective of shifts in water sourcing, it is particularly hot droughts that will lead to increasingly severe restrictions of grassland water dynamics., (© 2024 The Author(s). Plant, Cell & Environment published by John Wiley & Sons Ltd.)

Background/Introduction: Cardiac implantable electronic devices and their integrated thoracic impedance sensors have been used to detect sleep apnea for over a decade now. Despite their usage in daily clinical practice, there are only limited data on their diagnostic accuracy. Methods: AIRLESS and UPGRADE were prospective investigator-driven trials meant to validate the AP scan ® (Boston Scientific, Marlborough, MA, USA) in heart failure cohorts. Patients, who either fulfilled the criteria for implantation of an implantable cardioverter-defibrillator (ICD), cardiac resynchronization therapy (CRT), or upgrading to CRT according to most recent guidelines at the time of study conduction, were eligible for enrolment. Sleep apnea and its severity, measured by apnea-hypopnea index (AHI), were assessed by polysomnography. For direct comparison, the apnea sensor-derived AP scan ® was used from the identical night. Results: Overall, 80 patients were analyzed. Median AHI was 21.6 events/h (7.1-34.7), while median AP scan ® was 33.0 events/h (26.0-43.0). In the overall cohort, the sensor-derived AP scan ® correlated significantly with the AHI (r = 0.61, p < 0.001) with a mean difference (MD) of -12.6 (95% confidence interval (CI) -38.2 to 13.0). Furthermore, the AP scan ® was found to correlate well with the AHI in patients with obstructive sleep apnea r = 0.73, p = 0.011, MD -5.2, 95% CI -22.7 to 12.3), but not central sleep apnea (r = 0.28, p = 0.348, MD -10.4, 95% CI -35.4 to 14.6). Conclusions: In an exclusive heart failure cohort, the AP scan ® correlated well with the PSG-derived AHI. A similar correlation was found in most subgroups except for patients suffering from central sleep apnea.

Tourism in Paleolithic caves can cause an imbalance in cave microbiota and lead to cave wall alterations, such as dark zones. However, the mechanisms driving dark zone formation remain unclear. Using shotgun metagenomics in Lascaux Cave's Apse and Passage across two years, we tested metabarcoding-derived functional hypotheses regarding microbial diversity and metabolic potential in dark zones vs unmarked surfaces nearby. Taxonomic and functional metagenomic profiles were consistent across years but divergent between cave locations. Aromatic compound degradation genes were prevalent inside and outside dark zones, as expected from past biocide usage. Dark zones exhibited enhanced pigment biosynthesis potential (melanin and carotenoids) and melanin was evidenced chemically, while unmarked surfaces showed genes for antimicrobials production, suggesting that antibiosis might restrict the development of pigmented microorganisms and dark zone extension. Thus, this work revealed key functional microbial traits associated with dark zone formation, which helps understand cave alteration processes under severe anthropization., (© 2024. The Author(s).)

Background: Pulsed field ablation (PFA) is increasingly used in clinical practice for the treatment of atrial fibrillation. While the susceptibility of erythrocytes to electroporation is well established, the effect of cardiac PFA technologies on hemolysis has remained underreported. The aim of this study was to investigate the incidence, severity, and clinical impact of PFA-induced hemolysis., Methods: We included n=145 patients undergoing atrial fibrillation catheter ablation with a pentaspline PFA catheter (biphasic, bipolar pulses of 2 kV) and n=70 patients receiving radiofrequency ablation (40-90 W) at 4 high-volume European centers. The lesion set comprised pulmonary vein isolation for paroxysmal atrial fibrillation and pulmonary vein isolation±additional lesions for persistent atrial fibrillation. Hemolysis and renal function biomarkers were analyzed in blood samples at baseline, at the end of ablation, and 24 hours after the procedure., Results: Baseline characteristics were well balanced between groups (overall mean 65.7±9.4 years; 69.3% men). The ablation procedures comprised a mean of 61.6±27.4 PFA deliveries and 26.3±15.0 minutes RF duration. Hemolysis was detected in 94.3% versus 6.8% of patients after PFA versus radiofrequency ablation ( P <0.001): PFA was associated with significantly lower haptoglobin levels (0.5±0.4 versus 1.0±0.4 g/L), while free plasma hemoglobin (592.8±330.6 versus 147.8±183.0 mg/L), bilirubin (21.3±11.3 versus 14.8±8.8 µmol/L), and LDH (lactate dehydrogenase, 352.7±115.7 versus 253.2±56.5 U/L) were significantly higher after PFA compared with radiofrequency ablation (all P <0.001). Hemolysis correlated with the number of PFA deliveries (r=0.62 [95% CI, 0.33-0.80]; P <0.001), with the highest severity occurring ≥54 PFA deliveries. After PFA, hemoglobinuria occurred in 36.4%, while creatinine increase was higher in patients with baseline glomerular filtration rate <50 mL/min than with baseline glomerular filtration rate >50 mL/min (Δcrea, 27.0±103.1 versus -0.2±12.1 µmol/L; P =0.010)., Conclusions: Intravascular hemolysis is a frequent finding after PFA and increases with the number of PFA deliveries. Until the clinical impact of PFA-associated hemolysis is fully elucidated, a careful titration of PFA deliveries during the ablation procedure is warranted., Competing Interests: LIRYC, a research institute lead by Dr Jais, received an unrestricted research grant from Boston scientific. Dr Boveda is a consultant for Medtronic, Boston Scientific, Microport, and Zoll. The other authors report no conflicts.

Competing Interests: Conflict of interest: None declared.

Aims: Pulsed field ablation (PFA) has been proposed as a novel alternative to radiofrequency (RF) and cryoablation in the treatment of atrial fibrillation (AF). Following the occurrence of two cases of acute kidney injury (AKI) secondary to haemolysis after a PFA procedure, we evaluated haemolysis in a cohort of consecutive patients., Methods and Results: Two cases of AKI occurred in last May and June 2023. AKI was secondary to acute and severe haemolysis after a PFA procedure. From June 2023, a total of 68 consecutive patients (64.3 ± 10.5 years) undergoing AF ablation with PFA were enrolled in the study. All patients had a blood sample the day after the procedure for the assessment of haemolysis indicators. The pentaspline PFA catheter was used with a total number of median applications of 64 (54; 76). Nineteen patients (28%) showed significantly depleted haptoglobin levels (<0.04 g/L). A significant inverse correlation was found between the plasma level of haptoglobin and the total number of applications. Two groups were compared: the haemolysis+ group (haptoglobin < 0.04 g/L) vs. the haemolysis- group. The total number of applications was significantly higher in the haemolysis+ group vs the haemolysis - group respectively 75 (62; 127) vs 62 (54; 71) P = 0.011. More than 70 applications seem to have better sensitivity and specificity to predict haemolysis., Conclusion: Intravascular haemolysis can occur after certain procedures of PFA. Acute kidney injury is a phenomenon that appears to be very rare after a PFA procedure. However, caution must be exercised in the number of applications to avoid severe haemolysis., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Competing Interests: Funding Support and Author Disclosures The authors have reported that they have no relationships relevant to the contents to this paper to disclose.

Aims: The aim of this study was to compare procedural efficacy and safety, including 1-year freedom from AF recurrence, between the novel cryoballoon system PolarX (Boston Scientific) and the Arctic Front Advance Pro (AFA-Pro) (Medtronic), in patients with paroxysmal AF undergoing PVI., Methods and Results: This multicentre prospective observational study included 267 consecutive patients undergoing a first cryoablation procedure for paroxysmal AF (137 PolarX, 130 AFA-Pro). Kaplan-Meier curves with the log-rank test was used to compare the 1-year freedom from AF recurrence between both groups. Multivariate Cox model was performed to evaluate whether the type of procedure (PolarX vs. AFA-Pro) had an impact on the occurrence of AF recurrences after adjustment on potentially confounding factors. The PolarX reaches lower temperatures than the AFA-Pro (LSPV 52 ± 5, vs. 59 ± 6; LIPV 49 ± 6 vs. 56 ± 6; right superior pulmonary vein: 49 ± 6 vs. 57 ± 7; right inferior pulmonary vein: 52 ± 6 vs. 59 ± 6; P < 0.0001). A higher rate of transient phrenic nerve palsy was found in patients treated with the PolarX system (15% vs. 7%, P = 0.05). After a mean follow-up of 15 ± 5 months, 20 patients (15%) had recurrences in AFA-Pro group and 27 patients (19%) in PolarX group (P = 0.35). Based on survival analysis, no significant difference was observed between both groups with a 12-month free of recurrence survival of 91.2% (85.1-95.4%) vs. 83.7% (76.0%-89.1%) (log-rank test P = 0.11). In multivariate Cox model hazard ratio of recurrence for PolarX vs. AFA-Pro was not significant [HR = 1.6 (0.9-2.8), P = 0.12]., Conclusion: PolarX and AFA-Pro have comparable efficacy and safety profiles for pulmonary veins isolation in paroxysmal atrial fibrillation., Competing Interests: Conflicts of interest: G.C. received compensation for teaching purposes and proctoring from Medtronic, Abbott, Biotronik, Boston Scientific, Acutus Medical. C.d.A. receives research grants on behalf of the centre from Biotronik, Medtronic, Abbott, LivaNova, Boston Scientific, AtriCure, Philips, and Acutus; C.d.A. received compensation for teaching purposes and proctoring from Medtronic, Abbott, Biotronik, Livanova, Boston Scientific, Atricure, Acutus Medical Daiichi Sankyo. S.B. is consultant for Medtronic, Boston Scientific, Microport, and Zoll. P.D. receives research grants and honoraria from Boston Scientific, Medtronic, Abbott and Microport. Other authors declare no conflict of interest., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Introduction: Outcomes of catheter ablation for non-paroxysmal atrial fibrillation (AF) remain suboptimal. Non-invasive stratification of patients based on the presence of atrial cardiomyopathy (ACM) could allow to identify the best responders to pulmonary vein isolation (PVI)., Methods: Observational multicentre retrospective study in patients undergoing cryoballoon-PVI for non-paroxysmal AF. The duration of amplified P-wave (APW) was measured from a digitally recorded 12-lead electrocardiogram during the procedure. If patients were in AF, direct-current cardioversion was performed to allow APW measurement in sinus rhythm. An APW cut-off of 150 ms was used to identify patients with significant ACM. We assessed freedom from arrhythmia recurrence at long-term follow-up in patients with APW ≥ 150 ms vs. APW < 150 ms., Results: We included 295 patients (mean age 62.3 ± 10.6), of whom 193 (65.4%) suffered from persistent AF and the remaining 102 (34.6%) from long-standing persistent AF. One-hundred-forty-two patients (50.2%) experienced arrhythmia recurrence during a mean follow-up of 793 ± 604 days. Patients with APW ≥ 150 ms had a significantly higher recurrence rate post ablation compared to those with APW < 150 ms (57.0% vs. 41.6%; log-rank p  < 0.001). On a multivariable Cox-regression analysis, APW≥150 ms was the only independent predictor of arrhythmia recurrence post ablation (HR 2.03 CI 95% 1.28-3.21; p  = 0.002)., Conclusion: APW duration predicts arrhythmia recurrence post cryoballoon-PVI in persistent and long-standing persistent AF. An APW cut-off of 150 ms allows to identify patients with significant ACM who have worse outcomes post PVI. Analysis of APW represents an easy, non-invasive and highly reproducible diagnostic tool which allows to identify patients who are the most likely to benefit from PVI-only approach., Competing Interests: SB is a consultant for Medtronic and Boston Scientific. AC has received an educational grant from Abbott and consultant fees from Boston Scientific. RJS has received research grants and speaker fees from Abbott, Medtronic, Boston Scientific, Johnson and Johnson and is a shareholder of AI Rhythm. MF has received research support from Abbott; Chief Medical Officer, Founder and Shareholder of Echopoint Medical Ltd; Director, Founder and Shareholder of Rhythm AI and Founder and Shareholder of Epicardio Ltd. RJH is founder and shareholder of Rhythm AI Ltd. PDL has received educational grants from Medtronic and Boston Scientific, and is supported by UCLH Biomedicine NIHR and Barts BRC funding. The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Creta, Venier, Tampakis, Providencia, Sunny, Defaye, Earley, Finlay, Hunter, Lambiase, Papageorgiou, Schilling, Sporton, Andrikopoulos, Deschamps, Albenque, Cardin, Combes, Combes, Vinolas, Moreno-Weidmann, Huang, Eichenlaub, Müller-Edenborn, Arentz, Jadidi and Boveda.)