28 resultados para Glow discharge plasmas


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Interventional cardiology in a day-case setting might reduce logistic constraints on hospital resources. However, in contrast with coronary angioplasty, few data support the feasibility and safety of radiofrequency catheter ablation (RCA). The aim of this prospective, multicenter cohort study was to evaluate the feasibility and safety of RCA in 1,342 patients (814 men; mean age 57 +/- 17 years) considered eligible for ambulatory RCA, according to specific set of criteria, for common atrial flutter (n = 632), atrioventricular nodal reentrant tachycardia (n = 436), accessory pathways (n = 202), and atrial tachycardia (n = 72). Patients suitable for early discharge (4 to 6 hours after uncomplicated RCA) were scheduled for 1-month follow-up. Predictive factors for delayed complications were studied by multivariate analysis. Of the 1,342 enrolled patients, 1,270 (94.6%) were discharged the same day and followed for 1 month; no deaths occurred, and the readmission rate was 0.79% (95% confidence interval 0.30% to 1.27%). Six patients had significant puncture complications, 2 presented with symptomatic delayed pulmonary embolism, and 2 had new onset of poorly tolerated atrial flutter. None of these complications was life threatening. Multivariate analysis did not identify any significant independent predictors for delayed complications. In conclusion, these data suggest that same-day discharge after uncomplicated RCA for routine supraventricular arrhythmias is safe and may be applicable in clinical practice. This approach is known to be associated with significant patient satisfaction and cost savings and can be considered a first-line option in most patients who undergo routine ablation procedures.

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Two polycrystalline diamond surfaces, manufactured by chemical vapour deposition (CVD) technique, are investigated regarding their applicability as charge state conversion surfaces (CS) for use in a low energy neutral atom imaging instrument in space research. The capability of the surfaces for converting neutral atoms into negative ions via surface ionisation processes was measured for hydrogen and oxygen with particle energies in the range from 100 eV to 1 keV and for angles of incidence between 6 deg and 15 deg. We observed surface charging during the surface ionisation processes for one of the CVD samples due to low electrical conductivity of the material. Measurements on the other CVD diamond sample resulted in ionisation efficiencies of ~2 % for H and up to 12 % for O. Analysis of the angular scattering revealed very narrow and almost circular scattering distributions. Comparison of the results with the data of the CS of the IBEX-Lo sensor shows that CVD diamond has great potential as CS material for future space missions.

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REASONS FOR PERFORMING STUDY In clinical practice, veterinarians often depend on owner-reported signs to assess the clinical course of horses with recurrent airway obstruction (RAO). OBJECTIVES To test whether owner-reported information on frequency of coughing and observation of nasal discharge are associated with clinical, cytological and bronchoprovocation findings in RAO-affected horses in nonstandardised field conditions. STUDY DESIGN Cross-sectional study comparing healthy and RAO-affected horses. METHODS Twenty-eight healthy and 34 RAO-affected Swiss Warmblood horses were grouped according to owner-reported 'coughing frequency' and 'nasal discharge'. Differences between these groups were examined using clinical examination, blood gas analyses, endoscopic mucus scores, cytology of tracheobronchial secretion and bronchoalveolar lavage fluid, and airway hyperresponsiveness determined by plethysmography with histamine bronchoprovocation. RESULTS Frequently coughing horses differed most markedly from healthy control animals. Histamine bronchoprovocation-derived parameters were significantly different between the healthy control group and all RAO groups. Mucus grades and tracheobronchial secretion and bronchoalveolar lavage fluid neutrophil percentages had particularly high variability, with overlap of findings between groups. Owner satisfaction with the clinical status of the horse was high, even in severely affected horses. CONCLUSIONS Owner-reported coughing and nasal discharge are associated with specific clinical and diagnostic findings in RAO-affected horses in field settings. While airway hyperresponsiveness differentiates best between healthy horses and asymptomatic RAO-affected horses, the absence of coughing and nasal discharge does not rule out significant neutrophilic airway inflammation. Owner satisfaction with the clinical status of the horse was uninformative.

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BACKGROUND It is often assumed that horses with mild respiratory clinical signs, such as mucous nasal discharge and occasional coughing, have an increased risk of developing recurrent airway obstruction (RAO). HYPOTHESIS Compared to horses without any clinical signs of respiratory disease, those with occasional coughing, mucous nasal discharge, or both have an increased risk of developing signs of RAO (frequent coughing, increased breathing effort, exercise intolerance, or a combination of these) as characterized by the Horse Owner Assessed Respiratory Signs Index (HOARSI 1-4). ANIMALS Two half-sibling families descending from 2 RAO-affected stallions (n = 65 and n = 47) and an independent replication population of unrelated horses (n = 88). METHODS In a retrospective cohort study, standardized information on occurrence and frequency of coughing, mucous nasal discharge, poor performance, and abnormal breathing effort-and these factors combined in the HOARSI-as well as management factors were collected at intervals of 1.3-5 years. RESULTS Compared to horses without clinical signs of respiratory disease (half-siblings 7%; unrelated horses 3%), those with mild respiratory signs developed clinical signs of RAO more frequently: half-siblings with mucous nasal discharge 35% (P < .001, OR: 7.0, sensitivity: 62%, specificity: 81%), with mucous nasal discharge and occasional coughing 43% (P < .001, OR: 9.9, sensitivity: 55%, specificity: 89%); unrelated horses with occasional coughing: 25% (P = .006, OR = 9.7, sensitivity: 75%, specificity: 76%). CONCLUSIONS AND CLINICAL IMPORTANCE Occasional coughing and mucous nasal discharge might represent an increased risk of developing RAO.

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BACKGROUND Cold atmospheric plasma (CAP, i.e. ionized air) is an innovating promising tool in reducing bacteria. OBJECTIVE We conducted the first clinical trial with the novel PlasmaDerm(®) VU-2010 device to assess safety and, as secondary endpoints, efficacy and applicability of 45 s/cm(2) cold atmospheric plasma as add-on therapy against chronic venous leg ulcers. METHODS From April 2011 to April 2012, 14 patients were randomized to receive standardized modern wound care (n = 7) or plasma in addition to standard care (n = 7) 3× per week for 8 weeks. The ulcer size was determined weekly (Visitrak(®) , photodocumentation). Bacterial load (bacterial swabs, contact agar plates) and pain during and between treatments (visual analogue scales) were assessed. Patients and doctors rated the applicability of plasma (questionnaires). RESULTS The plasma treatment was safe with 2 SAEs and 77 AEs approximately equally distributed among both groups (P = 0.77 and P = 1.0, Fisher's exact test). Two AEs probably related to plasma. Plasma treatment resulted in a significant reduction in lesional bacterial load (P = 0.04, Wilcoxon signed-rank test). A more than 50% ulcer size reduction was noted in 5/7 and 4/7 patients in the standard and plasma groups, respectively, and a greater size reduction occurred in the plasma group (plasma -5.3 cm(2) , standard: -3.4 cm(2) ) (non-significant, P = 0.42, log-rank test). The only ulcer that closed after 7 weeks received plasma. Patients in the plasma group quoted less pain compared to the control group. The plasma applicability was not rated inferior to standard wound care (P = 0.94, Wilcoxon-Mann-Whitney test). Physicians would recommend (P = 0.06, Wilcoxon-Mann-Whitney test) or repeat (P = 0.08, Wilcoxon-Mann-Whitney test) plasma treatment by trend. CONCLUSION Cold atmospheric plasma displays favourable antibacterial effects. We demonstrated that plasma treatment with the PlasmaDerm(®) VU-2010 device is safe and effective in patients with chronic venous leg ulcers. Thus, larger controlled trials and the development of devices with larger application surfaces are warranted.

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Radiogenic He is produced by the decay of uranium and thorium in the Earth’s mantle and crust. From here, it is degassed to the atmosphere and eventually escapes to space. Assuming that all of the 4He produced is degassed, about 70% of the total He degassed from Earth comes from the continental crust. However, the outgoing flux of crustal He has not been directly measured at the Earth’s surface and the migration pathways are poorly understood. Here we present measurements of helium isotopes and the long-lived cosmogenic radio-isotope Kr in the deep, continental-scale Guarani aquifer in Brazil and show that crustal He reaches the atmosphere primarily by the surficial discharge of deep groundwater. We estimate that He in Guarani groundwater discharge accounts for about 20% of the assumed global flux from continental crust, and that other large aquifers may account for about 33%. Old groundwater ages suggest that He in the Guarani aquifer accumulates over half- to one-millionyear timescales. We conclude that He degassing from the continents is regulated by groundwater discharge, rather than episodic tectonic events, and suggest that the assumed steady state between crustal production and degassing of He, and its resulting atmospheric residence time, should be re-examined.

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Objectives: Depression is associated with poor prognosis in patients with cardiovascular disease (CVD). We hypothesized that depressive symptoms at discharge from a cardiac rehabilitation program are associated with an increased risk of future CVD-related hospitalizations. Methods: We examined 486 CVD patients (mean age = 59.8 ± 11.2) who enrolled in a comprehensive 3-month rehabilitation program and completed the depression subscale of the Hospital Anxiety and Depression Scale (HADS-D). At follow-up we evaluated the predictive value of depressive symptoms for CVD-related hospitalizations, controlling for sociodemographic factors, cardiovascular risk factors, and disease severity. Results: During a mean follow-up of 41.5 ± 15.6 months, 63 patients experienced a CVD-related hospitalization. The percentage of depressive patients (HADS-D ≥ 8) decreased from 16.9% at rehabilitation entry to 10.7% at discharge. Depressive symptoms at discharge from rehabilitation were a significant predictor of outcome (HR 1.32, 95% CI 1.09–1.60; p =0.004). Patients with clinically relevant depressive symptoms at discharge had a 2.5-fold increased relative risk of poor cardiac prognosis compared to patients without clinically relevant depressive symptoms independently of other prognostic variables. Conclusion: In patients with CVD, depressive symptoms at discharge from rehabilitation indicated a poor cardiac prognosis.

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We present an overview of a perturbative-kinetic approach to jet propagation, energy loss, and momentum broadening in a high temperature quark–gluon plasma. The leading-order kinetic equations describe the interactions between energetic jet-particles and a non-abelian plasma, consisting of on-shell thermal excitations and soft gluonic fields. These interactions include ↔ scatterings, collinear bremsstrahlung, and drag and momentum diffusion. We show how the contribution from the soft gluonic fields can be factorized into a set of Wilson line correlators on the light-cone. We review recent field-theoretical developments, rooted in the causal properties of these correlators, which simplify the calculation of the appropriate Wilson lines in thermal field theory. With these simplifications lattice measurements of transverse momentum broadening have become possible, and the kinetic equations describing parton transport have been extended to next-to-leading order in the coupling g.

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The evolution of landscapes crucially depends on the climate history. This is particularly evident in South America where landscape responses to orbital climate shifts have been well documented. However, while most studies have focused on inferring temperature variations from paleoclimate proxy data, estimates of water budget changes have been complicated because of a lack of adequate physical information. Here, we present a methodology and related results, which allowed us to extract water discharge values from the sedimentary record of the 40 Ka-old fluvial terrace deposits in the Pisco valley, western Peru. In particular, this valley hosts a Quaternary cut-and-fill succession that we used, in combination with beryllium-10 (10Be)-based sediment flux, gauging records, channel geometries and grain size measurements, to quantitatively assess sediment and water discharge values c. 40 Ka ago in relation to present-day conditions. We compare these discharge estimates to the discharge regime of the modern Pisco River and find that the water discharge of the paleo-Pisco River, during the Minchin pluvial period c. 40 Ka ago, was c. 7–8 times greater than the modern Pisco River if considering the mean and the maximum water discharge. In addition, the calculations show that inferred water discharge estimates are mainly dependent on channel gradients and grain size values, and to a lesser extent on channel width measures. Finally, we found that the c. 40 Ka-old Minchin terrace material was poorer sorted than the modern deposits, which might reflect that sediment transport during the past period was characterized by a larger divergence from equal mobility compared to the modern situation. In summary, the differences in grain size distribution and inferred water discharge estimates between the modern and the paleo-Pisco River suggests that the 40 Ka-old Minchin period was characterized by a wetter climate and more powerful flood events.

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Accurate rainfall data are the key input parameter for modelling river discharge and soil loss. Remote areas of Ethiopia often lack adequate precipitation data and where these data are available, there might be substantial temporal or spatial gaps. To counter this challenge, the Climate Forecast System Reanalysis (CFSR) of the National Centers for Environmental Prediction (NCEP) readily provides weather data for any geographic location on earth between 1979 and 2014. This study assesses the applicability of CFSR weather data to three watersheds in the Blue Nile Basin in Ethiopia. To this end, the Soil and Water Assessment Tool (SWAT) was set up to simulate discharge and soil loss, using CFSR and conventional weather data, in three small-scale watersheds ranging from 112 to 477 ha. Calibrated simulation results were compared to observed river discharge and observed soil loss over a period of 32 years. The conventional weather data resulted in very good discharge outputs for all three watersheds, while the CFSR weather data resulted in unsatisfactory discharge outputs for all of the three gauging stations. Soil loss simulation with conventional weather inputs yielded satisfactory outputs for two of three watersheds, while the CFSR weather input resulted in three unsatisfactory results. Overall, the simulations with the conventional data resulted in far better results for discharge and soil loss than simulations with CFSR data. The simulations with CFSR data were unable to adequately represent the specific regional climate for the three watersheds, performing even worse in climatic areas with two rainy seasons. Hence, CFSR data should not be used lightly in remote areas with no conventional weather data where no prior analysis is possible.