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1.
New Phytol ; 235(1): 52-65, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35478407

RESUMO

Today plants often flower earlier due to climate warming. Herbarium specimens are excellent witnesses of such long-term changes. However, the magnitude of phenological shifts may vary geographically, and the data are often clustered. Therefore, large-scale analyses of herbarium data are prone to pseudoreplication and geographical biases. We studied over 6000 herbarium specimens of 20 spring-flowering forest understory herbs from Europe to understand how their phenology had changed during the last century. We estimated phenology trends with or without taking spatial autocorrelation into account. On average plants now flowered over 6 d earlier than at the beginning of the last century. These changes were strongly associated with warmer spring temperatures. Flowering time advanced 3.6 d per 1°C warming. Spatial modelling showed that, in some parts of Europe, plants flowered earlier or later than expected. Without accounting for this, the estimates of phenological shifts were biased and model fits were poor. Our study indicates that forest wildflowers in Europe strongly advanced their phenology in response to climate change. However, these phenological shifts differ geographically. This shows that it is crucial to combine the analysis of herbarium data with spatial modelling when testing for long-term phenology trends across large spatial scales.


Assuntos
Mudança Climática , Flores , Europa (Continente) , Flores/fisiologia , Florestas , Plantas , Estações do Ano , Temperatura
2.
Proc Biol Sci ; 289(1971): 20212142, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35350857

RESUMO

Climate warming changes the phenology of many species. When interacting organisms respond differently, climate change may disrupt their interactions and affect the stability of ecosystems. Here, we used global biodiversity facility occurrence records to examine phenology trends in plants and their associated insect pollinators in Germany since the 1980s. We found strong phenological advances in plants but differences in the extent of shifts among pollinator groups. The temporal trends in plant and insect phenologies were generally associated with interannual temperature variation and thus probably driven by climate change. When examining the synchrony of species-level plant-pollinator interactions, their temporal trends differed among pollinator groups. Overall, plant-pollinator interactions become more synchronized, mainly because the phenology of plants, which historically lagged behind that of the pollinators, responded more strongly to climate change. However, if the observed trends continue, many interactions may become more asynchronous again in the future. Our study suggests that climate change affects the phenologies of both plants and insects and that it also influences the synchrony of plant-pollinator interactions.


Assuntos
Mudança Climática , Ecossistema , Animais , Insetos , Plantas , Estações do Ano , Temperatura
3.
Ecol Appl ; 31(5): e02332, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33765327

RESUMO

Many organisms respond to anthropogenic environmental change through shifts in their phenology. In plants, flowering is largely driven by temperature, and therefore affected by climate change. However, on smaller scales climatic conditions are also influenced by other factors, including habitat structure. A group of plants with a particularly distinct phenology are the understory herbs in temperate European forests. In these forests, management alters tree species composition (often replacing deciduous with coniferous species) and homogenizes stand structure, and as a consequence changes light conditions and microclimate. Forest management should thus also affect the phenology of understory herbs. To test this, we recorded the flowering phenology of 16 early-flowering herbs on 100 forest plots varying in management intensity, from near-natural to intensely managed forests, in central and southern Germany. We found that in forest stands with a high management intensity, such as Norway spruce plantations, the plants flowered on average about 2 weeks later than in unmanaged forests. This was largely because management also affected microclimate (e.g., spring temperatures of 5.9°C in managed coniferous, 6.7 in managed deciduous, and 7.0°C in unmanaged deciduous plots), which in turn affected phenology, with plants flowering later on colder and moister forest stands (+4.5 d per -1°C and 2.7 d per 10% humidity increase). Among forest characteristics, the percentage of conifers had the greatest influence on microclimate, but also the age, overall crown projection area, structural complexity and spatial distribution of the forest stands. Our study indicates that forest management alters plant phenology, with potential far-reaching consequences for the ecology and evolution of understorey communities. More generally, our study demonstrates that besides climate change other drivers of environmental change, too, can influence the phenology of organisms.


Assuntos
Mudança Climática , Árvores , Ecossistema , Flores , Estações do Ano
4.
Europace ; 23(6): 868-877, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-33458770

RESUMO

AIMS: Cryoballoon (CB) pulmonary vein isolation (PVI) is an accepted ablation strategy for rhythm control in atrial fibrillation (AF). We describe efficacy and safety in a high volume centre with a long experience in the use of the second-generation CB (CB2). METHODS AND RESULTS: Consecutive paroxysmal AF (PAF) or persistent AF (persAF) patients undergoing CB2-PVI were enrolled. Procedural data, efficacy, and safety issues were systematically collected. The 28 mm CB2 was used in combination with an inner lumen spiral catheter, a luminal oesophageal temperature (LET) probe was used with a cut-off of 15°C, the phrenic nerve (PN) monitored during septal PVs ablation. Freeze duration was mainly set at 240 s with a bonus application in case of delayed time-to-isolation (TTI > 75 s). A total of 1017 CB2 procedures were analysed (58% male, 66 ± 12 years old, 70% with PAF). 3964 PVs were identified, 99.8% PVs isolated using solely the 28 mm CB. Mean procedure time was 69 ± 25 min, TTI during the first application was recorded in 77% of PVs after a mean of 48 ± 31 s. We recorded 0.2% cardiac tamponade, 4.8% PN injury (1.6% of PN palsy), and 19% of LET < 15°C. Among 725 patients with follow-up data, 84% with PAF and 75% with persAF were in stable SR at 1 year. Shorter freezing duration and longer TTI were procedural predictors for recurrence. CONCLUSION: Cryoballoon procedures are fast and associated with a benign safety profile. Shorter TTI and longer freeze durations are associated with sinus rhythm during follow-up.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Criocirurgia , Veias Pulmonares , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Criocirurgia/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/cirurgia , Recidiva , Resultado do Tratamento
5.
JACC Clin Electrophysiol ; 6(10): 1253-1261, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33092751

RESUMO

OBJECTIVES: This study sought to investigate the safety profile of a novel ablation index-guided high-power short-duration (AI-HP) pulmonary vein isolation (PVI) in terms of endoscopic esophageal lesions. BACKGROUND: The risk of esophageal injury during PVI is a major concern while ablating the posterior wall for patients with atrial fibrillation. Luminal esophageal temperature (LET) rise during ablation is a surrogate for esophageal lesion development. METHODS: A total of 122 consecutive symptomatic atrial fibrillation patients underwent AI-HP PVI (50 W throughout the ablation, AI anterior wall/posterior wall: 550/400). All patients were under LET monitoring (cutoff LET 39°C) during the ablation procedure, and patients with LET rise received esophageal endoscopy examination 1 to 3 days after the ablation. Ablation lesion data of the sites with LET rise were analyzed. RESULTS: Procedural PVI success rate was 100%. Per procedure, the mean radiofrequency ablation time, procedural time, and fluoroscopic time were 11.9 ± 2.7 min, 54.8 ± 9 min, and 5.5 ± 1.6 min. The incidence of LET >39°C was 47%, and the mean peak LET was 41.2 ± 1.8°C. The rate of endoscopic detected lesion was 2 of 57 (3.5%). No perforation or atrial-esophageal fistula was found. The mean contact force, application duration, impedance drop, and AI values at the sites with LET rise were 22.1 ± 8.9 g, 7 ± 2.4 s, 9.4 ± 4.6 Ω, and 419 ± 44.6. CONCLUSIONS: AI-HP (50 W) ablation appears to be a highly efficient ablation technique for PVI. The incidence of esophageal injury during AI-HP PVI seems markedly low. AI-HP ablation targeting AI 400 in combination with multisensor esophageal temperature monitoring for the left atrial posterior wall appears safe and efficient.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Fibrilação Atrial/cirurgia , Endoscopia , Humanos , Veias Pulmonares/cirurgia
6.
J Cardiovasc Electrophysiol ; 31(8): 1923-1931, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32495488

RESUMO

BACKGROUND: Time-to-isolation (TTI) guided second-generation cryoballoon (CB2) ablation has been shown to be effective for pulmonary vein isolation (PVI). OBJECTIVE: The objective of this paper is to compare the safety and clinical outcome of CB2 PVI using the TTI guided 4 minutes vs 3 minutes freeze protocol. METHODS: This was a propensity-matched study based on an institutional database. Symptomatic atrial fibrillation (AF) patients who underwent CB2 PVI and systematic follow-up were consecutively included. RESULTS: A total of 573 patients were identified, of them 214 (107 matched-pairs) symptomatic AF (paroxysmal AF: 61%, persistent AF: 39%) patients (age: 67.7 ± 11.2 years) were analyzed. The baseline characteristics were comparable between the two groups. Procedural time was significantly longer in the 4 minutes group compared to 3 minutes group (67.2 ± 21.8 vs 55.9 ± 16.9 minutes, P < .0001). During a mean follow-up of 2 years, the 4 minutes group was associated with a significantly higher rate of freedom from arrhythmia recurrence compared with the 3 minutes group (66.4% vs 56.1%, P = .009), which was mainly driven by patients with persistent AF. The multivariate regression showed that the 4 minutes freeze was the independent predictor of freedom from arrhythmia recurrence. During the repeat procedure, the 4 minutes group was associated with a significantly higher rate of durable PVI. There was no difference regarding procedural adverse events between the two groups. CONCLUSION: As compared with the 3 minutes freeze, the TTI guided 4 minutes freeze is associated with a significantly higher rate of arrhythmia-free and durable PVI without compromising the safety profile, patients with persistent AF may benefit from the TTI guided 4 minutes freeze more pronouncedly.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Criocirurgia , Veias Pulmonares , Idoso , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Criocirurgia/efeitos adversos , Humanos , Veias Pulmonares/cirurgia , Recidiva , Fatores de Tempo , Resultado do Tratamento
7.
Heart Rhythm ; 17(11): 1833-1840, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32470628

RESUMO

BACKGROUND: High-power, short-duration ablation for pulmonary vein isolation (PVI) in the treatment of atrial fibrillation (AF) facilitates the procedure and improve effectiveness; however, esophageal injury remains a safety concern. OBJECTIVE: The purpose of this study was to investigate the role of luminal esophageal temperature (LET) monitoring during high-power ablation for PVI in terms of endoscopic esophageal lesion. METHODS: Patients with symptomatic AF underwent ablation index-guided high-power (AI-HP) PVI (50 W; AI anterior wall/posterior wall: 550/400). In the first consecutive set of patients, an insulated esophageal temperature probe was used for LET monitoring (cutoff LET >39°C) (group A). In the second consecutive set of patients, the probe was not used (group B). All patients were scheduled to undergo esophageal endoscopy 1-3 days after ablation. RESULTS: A total of 120 patients (60 group A; 60 group B) were included in the study (mean age 67.8 years; 64% male). Baseline characteristics and procedural outcomes were similar between the 2 groups. Procedural PVI was achieved in all patients. First-pass PVI rate was 96.6%. Mean procedural radiofrequency (RF) time was 11.5 minutes, mean procedural time was 55.5 minutes, and fluoroscopic time was 5.6 minutes. Mean contact force at the LA posterior wall was 23 g, and mean RF ablation time at the LA posterior wall was 3.2 minutes. Two patients in group A and 1 patient in group B had endoscopic small esophageal lesions (P = .99). No serious procedural adverse events were observed. CONCLUSION: Among patients undergoing AI-HP (50 W) PVI, the incidences of ablation-related endoscopic esophageal lesion in patients with and those without use of a temperature probe for LET monitoring (cutoff 39°C) were comparably low.


Assuntos
Fibrilação Atrial/cirurgia , Temperatura Corporal/fisiologia , Ablação por Cateter/métodos , Esôfago/fisiopatologia , Veias Pulmonares/cirurgia , Idoso , Fibrilação Atrial/fisiopatologia , Esofagoscopia , Feminino , Humanos , Masculino , Recidiva , Fatores de Tempo , Resultado do Tratamento
8.
Eur Urol ; 78(1): 16-20, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32362498

RESUMO

The current coronavirus disease 2019 (COVID-19) pandemic has placed considerable strain on hospital resources. We explored whether telemedicine (defined as a videoconference) might help. We undertook prospective structured phone interviews of urological patients (n = 399). We evaluated their suitability for telemedicine (judged by a panel of four physicians) and their risks from COVID-19 (10 factors for a poor outcome), and collected willingness for telemedicine and demographic data. Risk factors for an adverse outcome from COVID-19 infection were common (94.5% had one or more) and most patients (63.2%) were judged suitable for telemedicine. When asked, 84.7% of patients wished for a telemedical rather than a face-to-face consultation. Those favouring telemedicine were younger (68 [58-75] vs 76 [70-79.2] yr, p < 0.001). There was no difference in preference with oncological (mean 86%) or benign diagnoses (mean 85%), or with COVID-19 risks factors. In subgroup analysis, men with prostate cancer preferred telemedicine (odds ratio: 2.93 [1.07-8.03], p = 0.037). We concluded that many urological patients have risk factors for a poor outcome from COVID-19 and most preferred telemedicine consultations at this time. This appears to be a solution to offer contact-free continuity of care. PATIENT SUMMARY: Risk factors for a severe course of coronavirus disease 2019 are common (94.5%) in urology patients. Most patients wished for a telemedical consultation (84.7%). This appears to be a solution to offer contact-free continuity of care.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Transmissão de Doença Infecciosa/prevenção & controle , Pacientes Ambulatoriais , Pneumonia Viral/complicações , Consulta Remota/métodos , Telemedicina/métodos , Neoplasias Urológicas/complicações , COVID-19 , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Humanos , Oncologia/métodos , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Fatores de Risco , SARS-CoV-2 , Neoplasias Urológicas/diagnóstico
9.
New Phytol ; 221(1): 110-122, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30160314

RESUMO

During the last centuries, humans have transformed global ecosystems. With their temporal dimension, herbaria provide the otherwise scarce long-term data crucial for tracking ecological and evolutionary changes over this period of intense global change. The sheer size of herbaria, together with their increasing digitization and the possibility of sequencing DNA from the preserved plant material, makes them invaluable resources for understanding ecological and evolutionary species' responses to global environmental change. Following the chronology of global change, we highlight how herbaria can inform about long-term effects on plants of at least four of the main drivers of global change: pollution, habitat change, climate change and invasive species. We summarize how herbarium specimens so far have been used in global change research, discuss future opportunities and challenges posed by the nature of these data, and advocate for an intensified use of these 'windows into the past' for global change research and beyond.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Poluição Ambiental , Espécies Introduzidas , Plantas , Academias e Institutos , Dióxido de Carbono , Mudança Climática , Jardins , Indústrias , Metais Pesados/análise , Museus , Nitrogênio
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