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Pulsed-field ablation (PFA) is a nonthermal energy source for ablation of cardiac arrhythmias. This study investigated the prospective outcomes of a novel PFA generator in conjunction with a commercially available, contact force-sensing, focal ablation catheter. The purpose of this study was to assess the feasibility, safety, and lesion characteristics of point-by-point PFA in consecutive patients undergoing repeat ablation of atrial fibrillation (AF). The study involved reisolation of pulmonary veins (PVs) with electrical reconnection and the creation of an anterior line (AL) in patients with anterior substrate or durable pulmonary vein isolation (PVI). In 24 patients (46% female; mean age 67 ± 10 years; 67% persistent AF), successful reisolation of 27 of 27 reconnected PVs (100%) was performed. In 19 patients, AL ablation was performed, with bidirectional block in 16 (84%), median ablation time 26 [21, 33] minutes, and first-pass bidirectional block in 13 patients (68%). Acute AL reconduction occurred in 8 of 19 patients (42%). Among these 8 patients, a subsequent sustained block of the AL was achieved in 5 (63%). Ultra-high-density electroanatomic mapping revealed homogeneous but relatively large low-voltage areas in the ablated regions. Median procedural, left atrial dwell, and fluoroscopy times were 100 [90, 109] minutes, 83 [75, 98] minutes, and 10 [8, 13] minutes, respectively. No major or minor complications occurred. This study demonstrated feasibility, acute efficacy, and safety of point-by-point PFA for repeat PVI and AL ablation. Further studies are warranted to assess the long-term durability and comparison with established ablation methods. [Display omitted] [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) is advancing rapidly and continually evolving in various fields. Recently, the release of ChatGPT has sparked significant public interest. In this study, we revisit the '100 Important Questions Facing Plant Science' by leveraging ChatGPT as a valuable tool for generating thought-provoking questions relevant to plant science. These questions primarily revolve around the utilization of plants in product development, understanding plant mechanisms, plant–environment interactions, and enhancing plant traits, with an emphasis on sustainable product development. While ChatGPT may not capture certain crucial aspects highlighted by scientists, it offers valuable insights into the questions generated by experts. Our analysis demonstrates that ChatGPT can be cautiously employed as a supportive tool to facilitate, streamline, and expedite specific tasks in plant science. Large language models (LLMs) were recently made widely available to the public. ChatGPT is an LLM released in late 2022, which has received massive public attention and interest. A need has emerged to evaluate how ChatGPT and other such artificial intelligence (AI) tools can benefit plant science. Proper use of such AI tools can improve and expedite the scientific process. [ABSTRACT FROM AUTHOR]

This study shows the general exponential rise in microplastic accumulation in agricultural soils, with fertilizer application speeding up this increase, and future predictions of microplastic concentrations. Utilizing data from the Broadbalk winter wheat experiment at Rothamsted Research, UK, from 1846 to 2022, Poisson regression models were applied to microplastic counts under different soil treatments, including farmyard manure, inorganic fertilizers, and control conditions. A mass conversion factor was applied to obtain the w/w relationship. Results indicated a significant annual increase in microplastic concentrations across all treatments, with fertilized soils showing a notably higher accumulation rate. Our study forecasts that, in 50 and 100 years from now, soils treated with fertilizers are expected to reach microplastic concentrations of 168.9 mg kg−1 (95% CI: 60.32–473.09) and 1159 mg kg−1 (95% CI: 200.49–6699.8) respectively, levels converging on those used in many experiments. This highlights the urgent need for strategies to mitigate microplastic pollution in agricultural fields. The results also help to choose predicted concentrations in global change experiments, as well as to motivate further research to explore the mechanisms of microplastic accumulation and the integration of these insights into broader agricultural and ecological models to guide sustainable practices and environmental conservation. [Display omitted] • Poisson models forecast exponential microplastic growth in agricultural soil. • The annual percentage growth rate is 0.47% higher in soils with fertilizer usage. • Future soil microplastics could reach 0.67% w/w by 2122. [ABSTRACT FROM AUTHOR]

Background: Cardiac resynchronization therapy (CRT) is less effective in patients with atrial fibrillation (AF) because of impaired ventricular CRT capture.Objective: We investigated the effects of catheter ablation in patients with AF and previous nonresponse to CRT.Methods: Consecutive patients with AF and CRT nonresponse who underwent catheter ablation for AF were analyzed. CRT nonresponse was defined as one of the following: (1) reduced biventricular capture <95% due to rapidly conducted AF, (2) <1 point improvement in New York Heart Association (NYHA) class after CRT implantation, or (3) insufficient increase in left ventricular ejection fraction (LVEF; ≤5%) after CRT implantation.Results: Thirty-eight patients (8 women [21%]; mean age 68 ± 10 years; LVEF 30% ± 7%, biventricular capture 88.0% [25th, 75th percentile 75.3%, 98.5%]) underwent catheter ablation. One major and 1 minor complication occurred (1 lethal atrioesophageal fistula and 1 hemodynamically nonrelevant pericardial effusion). The Kaplan-Meier estimates for arrhythmia-free survival after single and multiple ablation procedures were 29% (95% confidence interval 16%-51%) and 67% (95% confidence interval 53%-86%) after 24 months. After a median follow-up of 817 days (25th, 75th percentile 179, 1741 days), biventricular capture and LVEF were significantly higher (median [25th, 75th percentile] 99% [96%, 99%], difference 8% [0.2%, 3.75%], P < .0001; mean 32.1% ± 9.1%, difference 2.2% ± 7.1%, P = .0225) and patients had a significantly lower functional NYHA class (28 of 37 patients with improvement of at least 1 point; P < .0001).Conclusion: Catheter ablation of AF significantly improves CRT response in patients with heart failure and concomitant AF in terms of increased biventricular capture and LVEF and improved functional NYHA class. [ABSTRACT FROM AUTHOR]

Background: Second-generation cryoballoon (CB2)-based pulmonary vein isolation (PVI) has demonstrated encouraging clinical results for the treatment of paroxysmal atrial fibrillation (AF) and persistent AF. However, rhythm follow-up after PVI is mainly based on Holter electrocardiography of limited duration.Objective: The purpose of this study was to assess the real AF burden following CB2-based PVI in patients with implanted cardiac devices.Methods: A total of 670 consecutive patients underwent CB2-based PVI at 3 electrophysiology centers. In 66 patients (9.9%), an implantable cardiac device with continuous monitor function was independently implanted before the procedure (device group). This patient cohort was compared to propensity score-matched patients without cardiac devices (n = 66; control group).Results: A total of 254 of 258 PVs (98.4%0 in the device group were successfully isolated using only CB2. Postprocedural device interrogation found no device or lead malfunction related to the procedure. Periprocedural complications were registered in 7 of 66 patients (11%) in the device group and in 6 of 66 patients (9%) in the control group (P = .770). Phrenic nerve palsy occurred in 6 of 66 patients (9%) in the device group) and in 2 of 66 patients (3%) in the control group) (P = .274). Clinical success in terms of freedom from AF recurrence after a 1-year follow-up period was 63.8% (95% confidence interval 53-77) in the device group and 77.3% (95% confidence interval 68-88) in the control group (P = .038). In the device group, AF/AT burden decreased from 41.8% ± 35.0% before the procedure to 10.2% ± 22.4% after 1 year (P <.0001).Conclusion: CB2-PVI seems safe and feasible in patients with an implanted cardiac device. A significantly higher AF/AT burden was seen in patients with an implanted cardiac device compared to a control group. [ABSTRACT FROM AUTHOR]

Microplastic is an emerging contaminant of concern in soils globally, probably gradually increasing in soil due to slow degradation. Few studies on microplastic effects on soil biota are available, and no study in a microplastic contamination context has specifically addressed soil protists. Soil protists, a phylogenetically and functionally diverse group of eukaryotic, unicellular soil organisms, are major consumers of bacteria in soils and are potentially important vehicles for the delivery of microplastics into the soil food chain. Here we build a case for focusing research on soil protists by drawing on data from previous, older studies of phagocytosis in protist taxa, which have long made use of polystyrene latex beads (microspheres). Various soil-borne taxa, including ciliates, flagellates and amoebae take up microplastic beads in the size range of a few micrometers. This included filter feeders as well as amoebae which engulf their prey. Discrimination in microplastic particle uptake depended on species, physiological state as well as particle size. Based on the results of the studies we review here, there is now a need to study microplastic effects in a pollution ecology context: this means considering a broad range of particle types under realistic conditions in the soil, and exploring longer-term effects on soil protist communities and functions. [ABSTRACT FROM AUTHOR]

Though typically discussed in the context of salinity, a shortage of sodium in tropical forests has been demonstrated in recent years, inhibiting soil biota with impacts on decomposition processes (Sodium Ecosystem Respiration hypothesis). So far, sodium limitation has been shown for soil fauna, whereas a potential role in saprotrophic fungi remains unknown. We tested the hypothesis that fungi have sodium demands at low levels resulting in reduced activity in tropical soils, analyzing fungal responses to sodium availability. Despite careful experimentation and the usage of different fungal strains we did not find evidence for fungal sodium demands using controlled nutrient media, not even in the absence of potassium. Likewise, there was no significant fungal response to sodium additions in litter samples, though decomposition rates were positively affected. These findings suggest that sodium is not essential for osmoregulation of tested fungal strains, which are hence not affected by sodium limitation. [ABSTRACT FROM AUTHOR]

Our knowledge of soil biodiversity in agriculture in general is currently increasing rapidly. However, almost all studies have stopped with the quantification of soil biodiversity effects on crops at harvest time, ignoring subsequent processes along the agrifood chain until food arrives on our plates. Here we develop a conceptual framework for the study of such postharvest effects. We present the main mechanisms (direct and indirect) via which soil biodiversity can influence crop quality aspects and give examples of how effects at harvest time may become attenuated through postharvest operations and how biodiversity may also affect some of these operations (i.e., storage) themselves. Future research with a broader focus has the potential to unveil how soil biodiversity may benefit from what ends up on our forks. [ABSTRACT FROM AUTHOR]

Background: Percutaneous catheter-based left atrial appendage closure (LAAC) is a procedure being increasingly performed in patients with atrial fibrillation and high bleeding risk.Objective: The purpose of this study was to evaluate the incidence of magnetic resonance imaging (MRI)-detected acute brain lesions (ABLs) as well as potential changes in neurocognitive function after percutaneous LAAC in patients with atrial fibrillation.Methods: Brain MRI at 3 T was performed within 24 hours before and after LAAC along with neurologic (National Institutes of Health Stroke Scale [NIHSS] score) and cognitive (Montreal Cognitive Assessment [MoCA] test) assessment. Acquired MRI sequences included high-resolution diffusion-weighted imaging as well as fluid-attenuated inversion recovery.Results: Successful device implantation was achieved in all 23 patients (age 74.1 ± 10.5 years; 16 male) using the Amulet (n = 18), Occlutech (n = 3), or LAmbre (n = 2) device. Thirty-seven ABLs were detected by MRI in 12 of 23 patients (52%) after LAAC. The number of periprocedural LAA angiographies was significantly higher in patients with ABL than in those without ABL (1.67 ± 0.65 vs 1.18 ± 0.41; P = .048) and was associated with a higher number of ABL (ρ = 0.615; P = .033). Compared to pre-LAAC assessment, post-LAAC MoCA and NIHSS scores revealed similar results. After LAAC, MoCA test (mean 24.1 ± 4.6 vs 23.2 ± 4.6; P = .09) and NIHSS score (mean 1.0 ± 1.7 vs 1.2 ± 1.8; P = .1) were similar between patients with and those without ABL, respectively.Conclusion: MRI-detected ABLs are commonly observed after percutaneous LAAC. The number of LAA angiographies is significantly associated with the number of ABLs; however, the clinical implications of ABL have yet to be determined. [ABSTRACT FROM AUTHOR]

Background: Second-generation cryoballoon (CB2)-based pulmonary vein isolation (PVI) has demonstrated encouraging clinical results in the treatment of paroxysmal (PAF) and persistent atrial fibrillation (PersAF). However, the CB2 features a maximal diameter of 28 mm, and its adaptability to anatomic variations of the pulmonary veins (PVs) might be challenging.Objective: The purpose of this study was to assess the acute efficacy, safety, and long-term clinical results of CB2-based PVI in patients with a left common pulmonary vein (LCPV).Methods: Six hundred seventy consecutive patients underwent CB2-based PVI in 3 electrophysiology centers. In 74 patients (11%), an LCPV was identified (LCPV group). The data were compared to those from matched patients (n = 74) with normal PV anatomy and comparable baseline characteristics (control group). An antral occlusion of the complete LCPV ostium was feasible in 50% of patients in the LCPV group. If an antral occlusion could not be obtained, a sequential isolation of the first superior and inferior branches was applied.Results: All 74 LCPVs were successfully isolated. A total of 64% patients (LCPV group) and 66% patients (control group) remained in sinus rhythm after mean follow-up of 1.9 ± 0.9 years (P = .820). In 18 of 26 patients (69%) with atrial tachyarrhythmia recurrence, a repeat procedure using radiofrequency energy was performed, and a total of 56% LCPVs were found to be persistently isolated (control group: 61% of left-sided PVs, P = .801).Conclusion: Patients with an LCPV undergoing CB2-based PVI demonstrate a high acute success rate. Comparable results with regard to clinical success and durability of PVI were shown when comparing patients of the LCPV group and the control group. [ABSTRACT FROM AUTHOR]

Plastics, despite their great benefits, have become a ubiquitous environmental pollutant, with microplastic particles having come into focus most recently. Microplastic effects have been intensely studied in aquatic, especially marine systems; however, there is lack of studies focusing on effects on soil and its biota. A basic question is if and how surface-deposited microplastic particles are transported into the soil. We here wished to test if soil microarthropods, using Collembola, can transport these particles over distances of centimeters within days in a highly controlled experimental set-up. We conducted a fully factorial experiment with two collembolan species of differing body size, Folsomia candida and Proisotoma minuta , in combination with urea-formaldehyde particles of two different particle sizes. We observed significant differences between the species concerning the distance the particles were transported. F. candida was able to transport larger particles further and faster than P. minuta . Using video, we observed F. candida interacting with urea-formaldehyde particles and polyethylene terephthalate fibers, showing translocation of both material types. Our data clearly show that microplastic particles can be moved and distributed by soil microarthropods. Although we did not observe feeding, it is possible that microarthropods contribute to the accumulation of microplastics in the soil food web. [ABSTRACT FROM AUTHOR]

Background: Extensive ablation strategies are currently performed in addition to pulmonary vein isolation (PVI) to improve the clinical outcome of patients with drug-refractory persistent atrial fibrillation (AF). Ablation of complex fractionated atrial electrograms (CFAEs), linear lesions, and/or isolation of the left atrial appendage (LAA) are thought to improve arrhythmia-free survival.Objective: The purpose of this study was to assess the durability of wide-area left atrial appendage isolation (LAAI) achieved by PVI, an anterior line, and a mitral isthmus line.Methods: Seventy-one patients with intentional or incidental LAAI during repeat catheter ablation for treatment of persistent AF were included. The initial ablation strategy was PVI. Additional ablation strategies were performed only if PVI failed to maintain stable sinus rhythm. Durability of LAAI was assessed during a subsequent ablation procedure for arrhythmia recurrences (n = 23) or a subsequent percutaneous LAA closure (n = 48).Results: LAAI was performed after a mean of 3 ± 1 procedures. Ablation strategies included circumferential PVI in 71 patients (100%), mitral isthmus line in 64 (90%), anterior line in 60 (85%), CFAE in 27 (38%), and roof line in 13 (18%). LAAI occurred after ablation and bidirectional block of LA linear lesions in 63 patients (89%) and during extensive CFAE ablation in 8 patients (11%). After a median of 105 [61;426] days, the LAA remained electrically isolated in 52 of 71 patients (73%).Conclusion: Wide-area LAAI after extensive catheter ablation for persistent AF is durable in the majority of patients. The potential clinical benefit of LAAI for maintaining stable sinus rhythm requires further investigation. [ABSTRACT FROM AUTHOR]

Background: The requirement for epicardial radiofrequency ablation (RFA) is still undefined in ventricular tachycardia (VT) late after myocardial infarction (MI).Objective: The purpose of this study was to evaluate the correlation between the need for epicardial RFA and the clinical and electrophysiologic characteristics of VT late after MI.Methods: Endocardial mapping and RFA were performed for VT late after MI, followed by epicardial mapping and RFA if no endocardial substrate was present or endocardial RFA failed.Results: Seventy patients with VT late after MI (30 anterior MI [A-MI] and 40 posteroinferior MI [PI-MI]) were included in the study. Forty-one VTs in patients with A-MI and 64 VTs in patients with PI-MI were targeted for RFA. Epicardial mapping and ablation were attempted in 6 patients and performed successfully in only 4 patients. All 6 (100%) patients requiring epicardial access had PI-MIs. Patients with epicardial RFA had endocardial low-voltage areas of smaller size compared to patients without epicardial RFA (21 ± 13 cm(2) vs 68 ± 40 cm(2); P <.01). During 25 ± 19 months of follow-up, recurrence after the initial procedure was noted in 12 of 30 patients (40%) with A-MI and in 18 of 40 patients (45%) with PI-MI. There was no significant difference between groups.Conclusion: In the majority of patients, clinical and slower VTs late after MI can be abolished using endocardial RFA. Rarely indicated, epicardial RFA is more commonly required in patients with small-sized PI-MI. During follow-up, VT recurrence after successful RFA is common. [ABSTRACT FROM AUTHOR]

Background: Ablation of the aortic sinus of Valsalva in adults for ectopic atrial tachycardia (EAT) and ventricular tachycardia (VT)/premature ventricular complexes (PVCs) has been reported in only a very few patients. Limited data exist concerning the safety of aortic ablation. Objective: The purpose of this study was to confirm aortic wall and aortic valve integrity after ablation and to evaluate for potential cerebral embolism due to thrombus formation at aortic wall lesions. Methods: From January 2006 to August 2007, 21 patients with EAT (n = 6) or VT/PVCs (n = 15) originating from the sinus of Valsalva underwent successful ablation. The aortic wall structure was evaluated using transesophageal echocardiography (TEE) and magnetic resonance imaging (MRI) the day after ablation and at 6-month follow-up for all patients. To rule out cerebral embolism due to postablation thromboembolic events, a cerebral MRI was performed immediately after ablation in six patients and at 6-month follow-up in all patients. Ablation success was defined by 24-hour Holter monitoring before hospital discharge and after 6 months. Results: Aortic wall integrity was confirmed in all patients by TEE and MRI. Cerebral MRI showed evidence of silent cerebral ischemia in one patient. Aortic valve thickening was detected in one patient by TEE. Conclusion: Ablation in the aortic sinus of Valsalva is a safe and effective approach for atrial tachycardia or VT/PVCs. The incidence of silent ischemia needs further evaluation. [ABSTRACT FROM AUTHOR]

Background: The efficacy of the second-generation cryoballoon (CB) in patients with paroxysmal atrial fibrillation (AF) has been demonstrated previously. Data on the efficacy of CB ablation in patients with persistent AF are sparse.Objective: The aim of this study was to evaluate the 2-year success rate of pulmonary vein isolation in patients with persistent AF using the second-generation CB.Methods: Fifty consecutive patients (mean age 64.6 ± 9.9 years; 19 women [38%]) with persistent AF were included in this analysis. The mean follow-up period was 22 ± 11 months. All patients were ablated using the second-generation 28-mm CB. Isolation of the pulmonary veins was confirmed using a spiral mapping catheter. In all patients, follow-up was obtained using 24-hour Holter monitoring or via interrogation of an implanted loop recorder or pacemaker.Results: The mean left atrial diameter was 43.6 ± 5.6 mm, the mean CHA2DS2-VASc score was 2.8 ± 1.5, and the mean HAS-BLED score was 2.1 ± 1.2. The mean fluoroscopy time was 25.8 ± 9 minutes, and the mean procedural time was 146.4 ± 37.8 minutes. After 22 ± 11 months, the frequency of arrhythmia recurrence was 22 of 50 (44%) in the overall group (paroxysmal AF 6 of 22 [27%]; persistent AF 16 of 22 [73%]). No major complications occurred. Aneurysma spurium not requiring surgical intervention occurred in 1 (2%) patient. No phrenic nerve palsy was observed.Conclusion: Two years' results after pulmonary vein isolation using the second-generation CB in patients with persistent AF are promising. The clinical success rate appears to be similar to the reported success rates of radiofrequency ablation for the treatment of persistent AF. [ABSTRACT FROM AUTHOR]

Most soil fungi experience a constantly fluctuating environment, and coping with resulting biotic and abiotic stressors can come at a considerable metabolic cost. We know that organisms respond better to severe stresses (triggering stress) when they have experienced a similar milder stress (priming stress) before. Asking how long organisms can remember a priming event is a compelling question. We here studied priming by temperature stress in filamentous fungi isolated from the same grassland soil. We hypothesized that filamentous fungi can show priming responses, and that their memory-spans correlate with their growth rates. Fungal colonies of 19 different filamentous fungi were first primed at 35 °C for 5 h (as priming stress) and after 0, 6, 12, 24 or 48 h they were exposed to 40 °C for 10 h (as triggering stress). The variable lag time between the stress applications allowed us to assess memory. Our main response variable was growth rate. Of the 19 fungal isolates tested, eight showed temperature priming ability. The Mucoromycotina isolates (Mortierellales) showed a mean growth increase following triggering stress that was 2.75-fold higher than in unprimed colonies (log-response-ratio). Mucoromycotina isolates had a memory half-life span (power-law-relationships) of 5.65 h. Considering fungal traits like growth rate to predict priming responses, we found a positive relationship between priming response (with 12 h memory phase) and growth rate. The differential ability to be primed in co-occurring isolates may have direct consequences for fungal communities and coexistence in soil. [ABSTRACT FROM AUTHOR]

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Community coalescence is a recently introduced term describing the interaction of entire communities and their environments. We here explicitly place the concept of community coalescence in a soil microbial context, exploring intrinsic and extrinsic drivers of such coalescence events. Examples of intrinsic events include the action of earthworms and the dynamics of soil aggregates, while extrinsic events are exemplified by tillage, flooding, litter-fall, outplanting, and the addition of materials containing microbial communities. Aspects of global change may alter the frequency or severity of coalescence events. We highlight functional consequences of community coalescence in soil, and suggest ways to experimentally tackle this phenomenon. Soil ecology as a whole stands to benefit from conceptualizing soil biodiversity in terms of dynamic coalescent microbial assemblages. [ABSTRACT FROM AUTHOR]

Soil aggregation is a key ecosystem process that strongly affects soil structure. Soil structure is the three dimensional arrangement of primary particles, organic matter, soil aggregates and associated pores. As such, soil aggregation influences the organization of soil biodiversity and soil-borne biogeochemical processes. Saprobic fungi (SF) have promising but largely untapped potential to offer new perspectives and insights into mechanisms of soil aggregation. The study of SF permits identification of traits that may predict soil aggregation component processes: formation, stabilization and disintegration. The measurement of fungal key traits in experiments aimed at soil aggregation effects will generate data necessary for mechanistic understanding. When such efforts are combined with collecting such information across a range of systems in curated databases this can, by channeling efforts, lead to a step change in our understanding and modeling of organism-mediated soil aggregation mechanisms and changes in functional diversity due to global change. [ABSTRACT FROM AUTHOR]

Microbial communities are enigmatically diverse. We propose a novel view of processes likely affecting microbial assemblages, which could be viewed as the Great American Interchange en miniature : the wholesale exchange among microbial communities resulting from moving pieces of the environment containing entire assemblages. Incidental evidence for such ‘community coalescence’ is accumulating, but such processes are rarely studied, likely because of the absence of suitable terminology or a conceptual framework. We provide the nucleus for such a conceptual foundation for the study of community coalescence, examining factors shaping these events, links to bodies of ecological theory, and we suggest modeling approaches for understanding coalescent communities. We argue for the systematic study of community coalescence because of important functional and applied consequences. [ABSTRACT FROM AUTHOR]

Background Left atrial appendage (LAA) closure devices have been introduced recently as an alternative for oral anticoagulation (OAC) in patients with nonvalvular atrial fibrillation (AF). Because of potential overlap of ablation target areas and the previously implanted LAA closure device, as well as potential complications such as mechanical damage to the device, left atrial (LA) ablation remains a subject of debate in these patients. Objective We report on the feasibility and clinical efficacy of LA ablation after implantation of LAA closure devices. Methods Eight patients (6 men; age 69 ± 8 years) with symptomatic paroxysmal AF (n = 5) or persistent AF (mean CHA 2 DS 2 -VASc score 3.6 ± 0.7, mean HAS-BLED score 3.6 ± 1.5) and previously implanted WATCHMAN (7 patients) or AMPLATZER Cardiac Plug (1 patient) LAA closure devices received radiofrequency-based LA ablation (4 via circumferential pulmonary vein isolation [CPVI], 4 via CPVI and additional LA linear lesions or complex fractionated atrial electrograms) after a mean of 201 days (range 41–756 days) after LAA closure. Results Successful LA ablation was achieved without device interference or periprocedural complications. After a mean of 503 days (range 113–1006 days), transesophageal echocardiography (TEE) was performed in all patients to assess for device-related complications. No device dislocation or leakage was observed. In 1 patient (12.5%), a device-related thrombus was found despite therapeutic OAC with dabigatran. Five patients (63%) remained in stable sinus rhythm, and no bleeding events or stroke occurred during a follow-up of 554 days (range 218–1006 days). Conclusion LA ablation after LAA closure appears to be feasible. Device-related thrombus formation in 1 patient suggests the need for further TEE examinations after LA ablation after LAA closure device implantation. [ABSTRACT FROM AUTHOR]

Fungal ecology lags behind in the use of traits ( i.e. phenotypic characteristics) to understand ecological phenomena. We argue that this is a missed opportunity and that the selection and systematic collection of trait data throughout the fungal kingdom will reap major benefits in ecological and evolutionary understanding of fungi. To develop our argument, we first employ plant trait examples to show the power of trait-based approaches in understanding ecological phenomena such as identifying species allocation resources patterns, inferring community assembly and understanding diversity–ecosystem functioning relationships. Second, we discuss ecologically relevant traits in fungi that could be used to answer such ecological phenomena and can be measured on a large proportion of the fungal kingdom. Third, we identify major challenges and opportunities for widespread, coordinated collection and sharing of fungal trait data. The view that we propose has the potential to allow mycologists to contribute considerably more influential studies in the area of fungal ecology and evolution, as has been demonstrated by comparable earlier efforts by plant ecologists. This represents a change of paradigm, from community profiling efforts through massive sequencing tools, to a more mechanistic understanding of fungal ecology. [ABSTRACT FROM AUTHOR]

The micronutrients copper (Cu), manganese (Mn) and iron (Fe) are essential for crop plant development and productivity. However, a quantitative, data-based consensus has yet to be reached on the role of arbuscular mycorrhizal fungi (AMF) in Cu, Mn and Fe nutrition in crops. Thus, we performed a meta-analysis to quantitatively synthesize the findings of 233 single publications and to test the impact of 10 moderator variables on the AM fungal mediated Cu, Mn and Fe aboveground tissue concentration. AMF had overall a significantly positive effect on crop Cu nutrition (on average 29%). For Fe, a positive AM fungal mediated effect was detectable only for intermediate 'experimental duration' (lasting 56-112 days). AMF only produced a positive effect on Mn nutrition in herbs, while for other plant types, edaphic and study-related factors we documented neutral or negative results. The application of AMF for crop plant fortification is still in its infancy. Here we found evidence for a significant role of AMF for Cu, Fe and (to a limited extent) Mn crop plant nutrition. This highlights that more efforts should be devoted to harnessing the potential beneficial effects of these symbionts not just for yield but also nutritional quality, especially considering increasing demands for food quality in the future. [ABSTRACT FROM AUTHOR]

The distribution of arbuscular mycorrhizal (AM) fungal abundance and diversity across multiple scales, and the factors that drive spatial patterns, remains largely unknown in arid ecosystems. We examined multiple measures of AM fungal abundance, as well as spore diversity and community composition, at microsite (1 m 2 ), local (1 ha), and regional (5000 ha) scales in semiarid shrublands. At the microsite scale, hyphae, spores, and glomalin-related soil protein were more abundant underneath shrub canopies, but unvegetated shrub interspaces had similar amounts of viable propagules, spore diversity, and spore community composition compared to canopies. Significant local and regional scale variation in abundance, diversity, and community composition were correlated with variation in soil organic matter, climate, and soil phosphorus concentration. We observed high alpha, beta, and gamma spore diversity and significant spatial autocorrelation of communities. This study demonstrates how multiple indicators of Glomeromycotan abundance and diversity vary differentially in natural systems and how soil and climate factors are important drivers of spatial patterns. [ABSTRACT FROM AUTHOR]

Allelopathy is a biological phenomenon where plants have harmful effects on growth of surrounding plants through the production of chemical substances. Here we focus on allelochemical processes which operate belowground, can influence plant interactions and therefore potentially affect plant community structure. Soil hyphae of arbuscular mycorrhizal fungi (AMF) may enhance transport processes in the soil matrix by providing direct connections between plants facilitating infochemical exchange. In a two-component field study we showed that soil hyphae likely play a crucial role in movement of allelochemicals in natural soils and greatly expand bioactive zones by providing effective transport pathways for chemical compounds. First, we tested the effects of Juglans regia leaf litter extract addition in intact or disrupted hyphal networks and simultaneously determined growth reducing effects on sensitive Lycopersicon lycopersicum plants. Second, we analyzed the effect of juglone on tomato by directly adding leaf litter. In both approaches we found an increase of juglone transport if a hyphal network was present, resulting in reduced growth of target plants. Our results, together with previous work, add to the body of evidence for hyphae of soil fungi playing an important role in the transfer of allelochemicals and effectively acting as transport highways in the field. We suggest that hyphal connections, mostly formed by AMF, increase the effectiveness of allelochemicals in natural systems and can play a crucial role in chemical interaction processes in the soil. [ABSTRACT FROM AUTHOR]

An increasing number of ecological studies compare the diversity of microbial taxa along environmental gradients or between imposed treatments. Estimates are often based on analysis-of-variance of taxon-richness inferred from pyrosequencing data. We conducted a reanalysis of three 454-pyrosequencing studies on arbuscular-mycorrhizal-fungal diversity to evaluate the suitability of using the Leinster and Cobbold diversity-indices (LCdis) to assess diversity. We expected that the potential of LCdis to consider phylogenic relationships could resolve problems arising from ambiguous species-delineation in microbial-systems. Our reanalysis showed that comparisons between studies differing considerably in sequencing depth may be risky. Moreover, we show that LCdis not only reproduce the results of analyses of variance but can also resolve issues connected to variation in sequence read number, while additionally representing a less conservative metric of diversity than analysis-of-variance of taxa-richness. Based on these results we advocate the use of inclusive diversity indices in ecological studies targeting microbial communities. [ABSTRACT FROM AUTHOR]