bluuebunny/crossref_metadata_2025_split huggingface dataset:
Radiofrequency Catheter Ablation of Atrial Fibrillation: A Cause of Silent Thromboembolism?
Authors: Gaita Fiorenzo , Caponi Domenico , Pianelli Martina , Scaglione Marco , Toso Elisabetta , Cesarani Federico , Boffano Carlo , Gandini Giovanni , Valentini Maria Consuelo , De Ponti Roberto , Halimi Franck , Leclercq Jean François 
Published: October 2010

Background—
Radiofrequency left atrial catheter ablation has become a routine procedure for treatment of atrial fibrillation. The aim of this study was to assess with preprocedural and postprocedural cerebral magnetic resonance imaging the thromboembolic risk, either silent or clinically manifest, in the context of atrial fibrillation ablation. The secondary end point was the identification of clinical or procedural parameters that correlate with cerebral embolism.

Methods and Results—

A total of 232 consecutive patients with paroxysmal or persistent atrial fibrillation who were candidates for radiofrequency left atrial catheter ablation were included in the study. Pulmonary vein isolation or pulmonary vein isolation plus linear lesions plus atrial defragmentation with the use of irrigated-tip ablation catheters was performed. All of the patients underwent preprocedural and postablation cerebral magnetic resonance imaging. A periprocedural symptomatic cerebrovascular accident occurred in 1 patient (0.4). Postprocedural cerebral magnetic resonance imaging was positive for new embolic lesions in 33 patients (14). No clinical parameters such as age, hypertension, diabetes mellitus, previous history of stroke, type of atrial fibrillation, and preablation antithrombotic treatment showed significant correlation with ischemic cerebral embolism. Procedural parameters such as activated clotting time value and, in particular, electric or pharmacological cardioversion to sinus rhythm correlated with an increased incidence of cerebral embolism. Cardioversion was also associated with an increased risk of 2.75 (95 confidence interval, 1.29 to 5.89;
P
=0.009).

Conclusions—
Radiofrequency left atrial catheter ablation carries a low risk of symptomatic cerebral ischemia but is associated with a substantial risk of silent cerebral ischemia detected on magnetic resonance imaging. Independent risk factors for cerebral thromboembolism are the level of activated clotting time and, in particular, the electric or pharmacological cardioversion to sinus rhythm during the procedure.
Cloud-Resolving Simulations of Deep Convection over a Heated Mountain
Authors: Kirshbaum Daniel J. 
Published: October 2010

AbstractCloud-resolving numerical simulations of airflow over a diurnally heated mountain ridge are conducted to explore the mechanisms and sensitivities of convective initiation under high pressure conditions. The simulations are based on a well-observed convection event from the Convective and Orographically Induced Precipitation Study (COPS) during summer 2007, where an isolated afternoon thunderstorm developed over the Black Forest mountains of central Europe, but they are idealized to facilitate understanding and reduce computational expense.In the conditionally unstable but strongly inhibited flow under consideration, sharp horizontal convergence over the mountain acts to locally weaken the inhibition and moisten the dry midtroposphere through shallow cumulus detrainment. The onset of deep convection occurs not through the deep ascent of a single updraft but rather through a rapid succession of thermals that are vented through the mountain convergence zone into the deepening cloud mass. Emerging thermals rise through the saturated wakes of their predecessors, which diminishes the suppressive effects of entrainment and allows for rapid glaciation above the freezing level as supercooled cloud drops rime onto preexisting ice particles. These effects strongly enhance the midlevel cloud buoyancy and enable rapid ascent to the tropopause. The existence and vigor of the convection is highly sensitive to small changes in background wind speed U0, which controls the strength of the mountain convergence and the ability of midlevel moisture to accumulate above the mountain. Whereas vigorous deep convection develops for U0 = 0 m s−1, deep convection is completely eliminated for U0 = 3 m s−1. Although deep convection is able to develop under intermediate winds (U0 = 1.5 m s−1), its formation is highly sensitive to small-amplitude perturbations in the initial flow.
Anthropogenic Influence on Long Return Period Daily Temperature Extremes at Regional Scales
Authors: Zwiers Francis W. , Zhang Xuebin , Feng Yang 
Published: October 2010

Abstract
Observed 1961–2000 annual extreme temperatures, namely annual maximum daily maximum (TXx) and minimum (TNx) temperatures and annual minimum daily maximum (TXn) and minimum (TNn) temperatures, are compared with those from climate simulations of multiple model ensembles with historical anthropogenic (ANT) forcing and with combined anthropogenic and natural external forcings (ALL) at both global and regional scales using a technique that allows changes in long return period extreme temperatures to be inferred. Generalized extreme value (GEV) distributions are fitted to the observed extreme temperatures using a time-evolving pattern of location parameters obtained from model-simulated extreme temperatures under ANT or ALL forcing. Evaluation of the parameters of the fitted GEV distributions shows that both ANT and ALL influence can be detected in TNx, TNn, TXn, and TXx at the global scale over the land areas for which there are observations, and also regionally over many large land areas, with detection in more regions in TNx. Therefore, it is concluded that the influence of anthropogenic forcing has had a detectable influence on extreme temperatures that have impacts on human society and natural systems at global and regional scales. External influence is estimated to have resulted in large changes in the likelihood of extreme annual maximum and minimum daily temperatures. Globally, waiting times for extreme annual minimum daily minimum and daily maximum temperature events that were expected to recur once every 20 yr in the 1960s are now estimated to exceed 35 and 30 yr, respectively. In contrast, waiting times for circa 1960s 20-yr extremes of annual maximum daily minimum and daily maximum temperatures are estimated to have decreased to fewer than 10 and 15 yr, respectively.
Global Ensemble Predictions of 2009’s Tropical Cyclones Initialized with an Ensemble Kalman Filter
Authors: Hamill Thomas M. , Whitaker Jeffrey S. , Fiorino Michael , Benjamin Stanley G. 
Published: October 2010

AbstractVerification was performed on ensemble forecasts of 2009 Northern Hemisphere summer tropical cyclones (TCs) from two experimental global numerical weather prediction ensemble prediction systems (EPSs). The first model was a high-resolution version (T382L64) of the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS). The second model was a 30-km version of the experimental NOAA/Earth System Research Laboratory’s Flow-following finite-volume Icosahedral Model (FIM). Both models were initialized with the first 20 members of a 60-member ensemble Kalman filter (EnKF) using the T382L64 GFS. The GFS–EnKF assimilated the full observational data stream that was normally assimilated into the NCEP operational Global Statistical Interpolation (GSI) data assimilation, plus human-synthesized “observations” of tropical cyclone central pressure and position produced at the National Hurricane Center and the Joint Typhoon Warning Center. The forecasts from the two experimental ensembles were compared against four operational EPSs from the European Centre for Medium-Range Weather Forecasts (ECMWF), NCEP, the Canadian Meteorological Centre (CMC), and the Met Office (UKMO).The errors of GFS–EnKF ensemble track forecasts were competitive with those from the ECMWF ensemble system, and the overall spread of the ensemble tracks was consistent in magnitude with the track error. Both experimental EPSs had much lower errors than the operational NCEP, UKMO, and CMC EPSs, but the FIM–EnKF tracks were somewhat less accurate than the GFS–EnKF. The ensemble forecasts were often stretched in particular directions, and not necessarily along or across track. The better-performing EPSs provided useful information on potential track error anisotropy. While the GFS–EnKF initialized relatively deep vortices by assimilating the TC central pressure estimate, the model storms filled during the subsequent 24 h. Other forecast models also systematically underestimated TC intensity (e.g., maximum forecast surface wind speed). The higher-resolution models generally had less bias.Analyses were conducted to try to understand whether the additional central pressure observation, the EnKF, or the extra resolution was most responsible for the decrease in track error of the experimental Global Ensemble Forecast System (GEFS)–EnKF over the operational NCEP. The assimilation of the additional TC observations produced only a small change in deterministic track forecasts initialized with the GSI. The T382L64 GFS–EnKF ensemble was used to initialize a T126L28 ensemble forecast to facilitate a comparison with the operational NCEP system. The T126L28 GFS–EnKF EPS track forecasts were dramatically better than the NCEP operational, suggesting the positive impact of the EnKF, perhaps through improved steering flow.
Cloud-Resolving Ensemble Simulations of Mediterranean Heavy Precipitating Events: Uncertainty on Initial Conditions and Lateral Boundary Conditions
Authors: Vié Benoît , Nuissier Olivier , Ducrocq Véronique 
Published: October 2010

Abstract
This study assesses the impact of uncertainty on convective-scale initial conditions (ICs) and the uncertainty on lateral boundary conditions (LBCs) in cloud-resolving simulations with the Application of Research to Operations at Mesoscale (AROME) model. Special attention is paid to Mediterranean heavy precipitating events (HPEs). The goal is achieved by comparing high-resolution ensembles generated by different methods. First, an ensemble data assimilation technique has been used for assimilation of perturbed observations to generate different convective-scale ICs. Second, three ensembles used LBCs prescribed by the members of a global short-range ensemble prediction system (EPS). All ensembles obtained were then evaluated over 31- and/or 18-day periods, and on 2 specific case studies of HPEs. The ensembles are underdispersive, but both the probabilistic evaluation of their overall performance and the two case studies confirm that they can provide useful probabilistic information for the HPEs considered.
The uncertainty on convective-scale ICs is shown to have an impact at short range (under 12 h), and it is strongly dependent on the synoptic-scale context. Specifically, given a marked circulation near the area of interest, the imposed LBCs rapidly overwhelm the initial differences, greatly reducing the spread of the ensemble. The uncertainty on LBCs shows an impact at longer range, as the spread in the coupling global ensemble increases, but it also depends on the synoptic-scale conditions and their predictability.
The Golden Radius in Balanced Atmospheric Flows
Authors: Willoughby H. E. 
Published: October 2010

Abstract
In gradient-balanced, cyclonic flow around low pressure systems, a golden radius exists where RG, the gradient-wind Rossby number, is φ−1 = 0.618 034, the inverse golden ratio. There, the geostrophic, cyclostrophic, and inertia-circle approximations to the wind all produce equal magnitudes. The ratio of the gradient wind to any of these approximations is φ−1. In anomalous (anticyclonic) flow around a low, the golden radius falls where RG = −φ = −1.618 034, and the magnitude of the ratio of the anomalous wind to any of the two-term approximations is φ. In normal flow, the golden radius marks the transition between more-nearly cyclostrophic and more-nearly geostrophic regimes. In anomalous flow, it marks the transition between more-nearly cyclostrophic (anticyclonic) and inertia-circle regimes. Over a large neighborhood surrounding the golden radius, averages of the geostrophic and cyclostrophic winds weighted as φ−2 and φ−3 are good approximations to the gradient wind. In high pressure systems Rg, the geostrophic Rossby number, must be in the range 0 &gt; Rg ≥ −¼, and the pressure gradient cannot produce inward centripetal accelerations. An analogous radius where Rg = −φ−3 plays a role somewhat like that of the golden radius, but it is much less interesting.
Seasonal, Regional, and Storm-Scale Variability of Cloud-to-Ground Lightning Characteristics in Florida
Authors: Rudlosky Scott D. , Fuelberg Henry E. 
Published: October 2010

Abstract
Seasonal, regional, and storm-scale variations of cloud-to-ground (CG) lightning characteristics in Florida are presented. Strong positive CG (+CG) and negative CG (−CG) flashes (i.e., having large peak current) are emphasized since they often are associated with strong storms, structural damage, and wildfire ignitions. Although strong −CG flashes are most common during the warm season (May–September) over the peninsula, the greatest proportion of strong +CG flashes occurs during the cool season (October–April) over the panhandle. The warm season exhibits the smallest +CG percentage but contains the greatest +CG flash densities, due in part to more ambiguous +CG reports (15–20 kA). The more frequent occurrence of ambiguous +CG reports helps explain the unusually small average +CG peak current during the warm season, whereas strong +CG reports (&gt;20 kA) appear to be responsible for the greater average warm season +CG multiplicity. The −CG flash density, multiplicity, and peak current appear to be directly related, exhibiting their greatest values during the warm season when deep storms are most common. A case study examines the atmospheric conditions and storm-scale processes associated with two distinct groups of storms on 13–14 May 2007. Although these groups of storms form in close proximity, several factors combine to produce predominately strong +CG and −CG flashes in the northern (south Georgia) and southern (north Florida) regions, respectively. Results suggest that heat and smoke very near preexisting wildfires are key ingredients in producing reversed-polarity (+CG dominated) storms that often ignite subsequent wildfires.
Sustained pain freedom and no adverse events as an endpoint in clinical trials of acute migraine treatments: Application to patient-level data from a trial of the CGRP receptor antagonist, telcagepant, and zolmitriptan
Authors: Dodick David W , Kost James , Assaid Christopher , Lines Christopher , Ho Tony W 
Published: October 2010

Background: Endpoints used to evaluate the efficacy of acute anti-migraine drugs do not measure the tolerability. Sustained pain-free response with no adverse events has been recommended as a composite endpoint which measures the efficacy and tolerability attributes that patients desire. Methods: The aim of this study was to evaluate new composite efficacy-plus-tolerability endpoints based on a post-hoc analysis of patient-level data from a previous randomized, placebo-controlled trial of the calcitonin gene-related peptide (CGRP) receptor antagonist, telcagepant, and zolmitriptan in the acute treatment of migraine. Endpoints were 2–24-hour sustained pain freedom and no adverse events from 0–24 hours (SPF24NAE), 2–24 hour sustained pain relief and no adverse events from 0–24 hours (SPR24NAE), pain freedom at 2 hours and no adverse events from 0–24 hours (PF2NAE), and pain relief at 2 hours and no adverse events from 0–24 hours (PR2NAE). Results: Compared with placebo, both telcagepant 300 mg and 150 mg achieved nominal superiority ( p values <.05) for SPF24NAE, SPR24NAE, PF2NAE and PR2NAE. Zolmitriptan 5 mg showed nominal superiority versus placebo for SPF24NAE, SPR24NAE and PF2NAE, but not PR2NAE. Telcagepant 300 mg showed nominal superiority versus zolmitriptan for SPF24NAE, SPR24NA and PR2NAE. Conclusion: Composite efficacy-plus-tolerability endpoints may be useful for facilitating comparisons between treatments.
Acute Osteoclast Activity following Subchondral Drilling Is Promoted by Chitosan and Associated with Improved Cartilage Repair Tissue Integration
Authors: Chen G. , Sun J. , Lascau-Coman V. , Chevrier A. , Marchand C. , Hoemann Caroline D. 
Published: October 2010

Objective:Cartilage-bone integration is an important functional end point of cartilage repair therapy, but little is known about how to promote integration. We tested the hypothesis that chitosan-stabilized blood clot implant elicits osteoclasts to drilled cartilage defects and promotes repair and cartilage-bone integration.Design:Bilateral trochlear defects in 15 skeletally mature rabbit knees were microdrilled and then treated with chitosan–glycerol phosphate (GP)/blood implant with fluorescent chitosan tracer and thrombin to accelerate in situ solidification or with thrombin alone. Chitosan clearance, osteoclast density, and osteochondral repair were evaluated at 1, 2, and 8 weeks at the outside, edge, and through the proximal microdrill holes.Results:Chitosan was retained at the top of the drill holes at 1 week as extracellular particles became internalized by granulation tissue cells at 2 weeks and was completely cleared by 8 weeks. Osteoclasts burst-accumulated at microdrill hole edges at 1 week, in new woven bone at the base of the drill holes at 2 weeks, and below endochondral cartilage repair at 8 weeks. Implants elicited 2-fold more osteoclasts relative to controls ( P < 0.001), a more complete drill hole bone repair, and improved cartilage-bone integration and histological tissue quality. Treated and control 8-week cartilage repair tissues contained 85% collagen type II. After 8 weeks of repair, subchondral osteoclast density correlated positively with bone-cartilage repair tissue integration ( P < 0.0005).Conclusions:Chitosan-GP/blood implant amplified the acute influx of subchondral osteoclasts through indirect mechanisms, leading to significantly improved repair and cartilage-bone integration without inducing net bone resorption. Osteoclasts are cellular mediators of marrow-derived cartilage repair integration.
Impaired angiogenesis and altered Notch signaling in mice overexpressing endothelial Egfl7
Authors: Nichol Donna , Shawber Carrie , Fitch Michael J. , Bambino Kathryn , Sharma Anshula , Kitajewski Jan , Stuhlmann Heidi 
Published: October 2010

AbstractEpidermal growth factor-like domain 7 (Egfl7) is important for regulating tubulogenesis in zebrafish, but its role in mammals remains unresolved. We show here that endothelial overexpression of Egfl7 in transgenic mice leads to partial lethality, hemorrhaging, and altered cardiac morphogenesis. These defects are accompanied by abnormal vascular patterning and remodeling in both the embryonic and postnatal vasculature. Egfl7 overexpression in the neonatal retina results in a hyperangiogenic response, and EGFL7 knockdown in human primary endothelial cells suppresses endothelial cell proliferation, sprouting, and migration. These phenotypes are reminiscent of Notch inhibition. In addition, our results show that EGFL7 and endothelial-specific NOTCH physically interact in vivo and strongly suggest that Egfl7 antagonizes Notch in both the postnatal retina and in primary endothelial cells. Specifically, Egfl7 inhibits Notch reporter activity and down-regulates the level of Notch target genes when overexpressed. In conclusion, we have uncovered a critical role for Egfl7 in vascular development and have shown that some of these functions are mediated through modulation of Notch signaling.
Nature and severity of lung function abnormalities in extremely pre-term children at 11 years of age
Authors: Lum S. , Kirkby J. , Welsh L. , Marlow N. , Hennessy E. , Stocks J. 
Published: October 2010

Advances in neonatal care have resulted in increased survival of children born extremely pre-term (EP). Nevertheless the incidence of bronchopulmonary dysplasia and long-term respiratory morbidity remains high. We investigated the nature of pathophysiological changes at 11 yrs of age to ascertain whether respiratory morbidity in EP children primarily reflects alterations in the lung periphery or more centralised airway function in this population.Spirometry, plethysmography, diffusing capacity, exhaled nitric oxide, multiple-breath washout, skin tests and methacholine challenge were used during laboratory-based assessments in a subgroup of the 1995 EPICure cohort and in controls.Results were obtained in 49 EP and 52 control children. Lung function abnormalities were found in 78% of EP children, with evidence of airway obstruction, ventilation inhomogeneity, gas trapping and airway hyperresponsiveness. Levels of atopy and exhaled nitric oxide were similar between the groups. Prior wheeze was associated with significant reductions in forced flows and volumes. By contrast, abnormalities of the lung periphery appear to be mediated primarily through EP birthper se.The prevalence of lung function abnormalities, which is largely obstructive in nature and likely to have long-term implications, remains high among 11-yr-old children born EP. Spirometry proved an effective means of detecting these persistent abnormalities.
Association of phospholipase A2 receptor 1 polymorphisms with idiopathic membranous nephropathy in Chinese patients in Taiwan
Authors: Liu Yu-Huei , Chen Cheng-Hsu , Chen Shih-Yin , Lin Ying-Ju , Liao Wen-Ling , Tsai Chang-Hai , Wan Lei , Tsai Fuu-Jen 
Published: October 2010

Abstract

Background
Idiopathic membranous nephropathy (IMN) is one of the most common forms of autoimmune nephritic syndrome in adults. The purpose of this study is to evaluate whether polymorphisms of PLA2R1 affect the development of IMN.

Methods
Taiwanese-Chinese individuals (129 patients with IMN and 106 healthy controls) were enrolled in this study. The selected single nucleotide polymorphisms (SNPs) in PLA2R1 were genotyped by real-time polymerase chain reaction using TaqMan fluorescent probes, and were further confirmed by polymerase chain reaction-restriction fragment length polymorphism. The roles of the SNPs in disease progression were analyzed.

Results
Genotype distribution was significantly different between patients with IMN and controls for PLA2R1 SNP rs35771982 (p = 0.015). The frequency of G allele at rs35771982 was significantly higher in patients with IMN as compared with controls (p = 0.005). In addition, haplotypes of PLA2R1 may be used to predict the risk of IMN (p = 0.004). Haplotype H1 plays a role in an increased risk of IMN while haplotype H3 plays a protective role against this disease. None of these polymorphisms showed a significant and independent influence on the progression of IMN and the risk of end-stage renal failure and death (ESRF/death). High disease progression in patients having C/T genotype at rs6757188 and C/G genotype at rs35771982 were associated with a low rate of remission.

Conclusions
Our results provide new evidence that genetic polymorphisms of PLA2R1 may be the underlying cause of IMN, and the polymorphisms revealed by this study warrant further investigation.