scholarly journals the Eole experiment: early results and current objectives

1973 ◽  
Vol 54 (4) ◽  
pp. 298-306 ◽  
Author(s):  
Pierre Morel ◽  
William Bandeen
Keyword(s):  
Eddy Diffusion ◽  
Scale Dependence ◽  
Relative Dispersion ◽  
Small Scale ◽  
Air Masses ◽  
Early Results ◽  
The Mean ◽  
Logarithmic Law ◽  
The Tropics ◽  
Launching Site

The Eole Experiment with 480 constant level balloons released in the Southern Hemisphere is described. Each balloon, floating freely at approximately the 200-mb level, is a precise tracer of the horizontal motion of air masses, the accuracy of which is limited only by the laminated structure of the stratospheric flow, within an rms uncertainty of 1.5 m sec−1. The balloons were found after 2 months to distribute at random over the whole hemisphere outside the tropics, irrespective of their original launching site. Early results of Eulerian and Lagrangian averages of the Eole wind data are given for describing the mean 200-mb zonal and meridional circulations. The effect of the small scale eddies of two-dimensional turbulence has been studied with respect to the relative eddy diffusion of pairs of balloons and the relative dispersion of triangular clusters. New estimates of the rms divergence of the 200-mb flow are given, together with their scale dependence which was found to be a logarithmic law.

scholarly journals The Key Physical Parameters Governing Frictional Dissipation in a Precipitating Atmosphere

2013 ◽  
Vol 70 (9) ◽  
pp. 2916-2929 ◽  
Author(s):  
A. M. Makarieva ◽  
V. G. Gorshkov ◽  
A. V. Nefiodov ◽  
D. Sheil ◽  
A. D. Nobre ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Atmospheric Circulation ◽  
Lapse Rate ◽  
Small Scale ◽  
Dynamic Power ◽  
True Value ◽  
Frictional Dissipation ◽  
The Mean ◽  
Degree Of Condensation ◽  
The Tropics

Abstract Precipitation generates small-scale turbulent air flows—the energy of which ultimately dissipates to heat. The power of this process has previously been estimated to be around 2–4 W m−2 in the tropics: a value comparable in magnitude to the dynamic power of global atmospheric circulation. Here it is suggested that the true value is approximately half the value of this previous estimate. The result reflects a revised evaluation of the mean precipitation pathlength HP. The dependence of HP on surface temperature, relative humidity, temperature lapse rate, and degree of condensation in the ascending air were investigated. These analyses indicate that the degree of condensation, defined as the relative change of the saturated water vapor mixing ratio in the region of condensation, is a major factor determining HP. From this theory the authors develop an estimate indicating that the mean large-scale rate of frictional dissipation associated with total precipitation in the tropics lies between 1 and 2 W m−2 and show empirical evidence in support of this estimate. Under terrestrial conditions frictional dissipation is found to constitute a minor fraction of the dynamic power of condensation-induced atmospheric circulation, which is estimated to be at least 2.5 times larger. However, because HP increases with increasing surface temperature Ts, the rate of frictional dissipation would exceed the power of condensation-induced dynamics, and thus block major circulation, at Ts ≳ 320 K in a moist adiabatic atmosphere.

Quantification of small-scale heterogeneity in aquatic aminopeptidase activity

2020 ◽  
Vol 84 ◽  
pp. 127-140
Author(s):  
BM Gaas ◽  
JW Ammerman
Keyword(s):  
Chlorophyll Fluorescence ◽  
Leucine Aminopeptidase ◽  
Hudson River ◽  
Aminopeptidase Activity ◽  
Small Scale ◽  
Analysis Instrument ◽  
Sequential Samples ◽  
Degree Of Confidence ◽  
The Mean ◽  
Hydrolysis Of

Leucine aminopeptidase (LAP) is one of the enzymes involved in the hydrolysis of peptides, and is sometimes used to indicate potential nitrogen limitation in microbes. Small-scale variability has the potential to confound interpretation of underlying patterns in LAP activity in time or space. An automated flow-injection analysis instrument was used to address the small-scale variability of LAP activity within contiguous regions of the Hudson River plume (New Jersey, USA). LAP activity had a coefficient of variation (CV) of ca. 0.5 with occasional values above 1.0. The mean CVs for other biological parameters—chlorophyll fluorescence and nitrate concentration—were similar, and were much lower for salinity. LAP activity changed by an average of 35 nmol l-1 h-1 at different salinities, and variations in LAP activity were higher crossing region boundaries than within a region. Differences in LAP activity were ±100 nmol l-1 h-1 between sequential samples spaced <10 m apart. Variogram analysis indicated an inherent spatial variability of 52 nmol l-1 h-1 throughout the study area. Large changes in LAP activity were often associated with small changes in salinity and chlorophyll fluorescence, and were sensitive to the sampling frequency. This study concludes that LAP measurements in a sample could realistically be expected to range from zero to twice the average, and changes between areas or times should be at least 2-fold to have some degree of confidence that apparent patterns (or lack thereof) in activity are real.

Outcomes of the Extracardiac Fontan Procedure Using Cardiopulmonary Bypass: Early Results

2014 ◽  
Vol 17 (3) ◽  
pp. 173 ◽  
Author(s):  
Murat Ugurlucan ◽  
Eylem Yayla Tuncer ◽  
Fusun Guzelmeric ◽  
Eylul Kafali ◽  
Omer Ali Sayin ◽  
...  
Keyword(s):  
Cardiopulmonary Bypass ◽  
Fontan Procedure ◽  
Fontan Operation ◽  
Arterial Oxygen Saturation ◽  
Vena Cava ◽  
Arterial Oxygen ◽  
Shunt Operation ◽  
Early Results ◽  
The Mean ◽  
Extracardiac Fontan

<p><strong>Background</strong>: Although the avoidance of cardiopulmonary bypass during the Fontan procedure has potential advantages, using cardiopulmonary bypass during this procedure has no adverse effects in terms of morbidity and mortality rates. In this study, we assessed the postoperative outcomes of our first 9 patients who have undergone extracardiac Fontan operation by the same surgeon using cardiopulmonary bypass.</p><p><strong>Methods</strong>: Between September 2011 and April 2013,  9 consecutive patients (3 males and 6 females) underwent extra-cardiac Fontan operation. All operations were performed under cardiopulmonary bypass at normothermia by the same surgeon.  The age of patients ranged between 4 and 17 (9.8 ± 4.2) years. Previous operations performed on these patients were modified Blalock-Taussig shunt procedure in 2 patients, bidirectional cavopulmonary shunt operation in 6 patients, and pulmonary arterial banding in 1 patient. Except 2 patients who required intracardiac intervention, cross-clamping was not applied. In all patients, the extracardiac Fontan procedure was carried out by interposing an appropriately sized tube graft between the infe-rior vena cava and right pulmonary artery.</p><p><strong>Results</strong>: The mean intraoperative Fontan pressure and transpulmonary gradient were 12.3 ± 2.5 and 6.9 ± 2.2 mm Hg, respectively. Intraoperative fenestration was not required. There was no mortality and 7 patients were discharged with-out complications. Complications included persistent pleural effusion in 1 patient and a transient neurological event in 1 patient. All patients were weaned off mechanical ventila-tion within 24 hours. The mean arterial oxygen saturation increased from 76.1% ± 5.3% to 93.5% ± 2.2%. All patients were in sinus rhythm postoperatively. Five patients required blood and blood-product transfusions. The mean intensive care unit and hospital stay periods were 2.9 ± 1.7 and 8.2 ±  1.9 days, respectively.</p><p><strong>Conclusions</strong>: The extracardiac Fontan operation per-formed using cardiopulmonary bypass provides satisfactory results in short-term follow-up and is associated with favor-able postoperative hemodynamics and morbidity rates.</p>

Hybrid Endovascular Repair of Thoracoabdominal Aorta: Early Results

2014 ◽  
Vol 17 (3) ◽  
pp. 146
Author(s):  
Osman Tansel Darcin ◽  
Mehmet Kalender ◽  
Ayse Gul Kunt ◽  
Okay Guven Karaca ◽  
Ata Niyazi Ecevit ◽  
...  
Keyword(s):  
Endovascular Repair ◽  
Therapeutic Option ◽  
Complete Recovery ◽  
Aortic Aneurysms ◽  
Thoracoabdominal Aorta ◽  
Mortality And Morbidity ◽  
Early Results ◽  
The Mean ◽  
Procedural Success

<p><b>Background:</b> Thoracoabdominal aortic aneurysms (TAAA) present a significant clinical challenge, as they are complex and require invasive surgery. In an attempt to prevent considerably high mortality and morbidity in open repair, hybrid endovascular repair has been developed by many authors. In this study, we evaluated the early-term results obtained from this procedure.</p><p><b>Methods:</b> From November 2010 to February 2013, we performed thoracoabdominal hybrid aortic repair in 18 patients. The mean age was 68 years (12 men, 6 women). All of the patients had significant comorbidities. Follow-up computed tomography (CT) scans were performed at 1 week, 3 months, 6 months, and annually thereafter.</p><p><b>Results:</b> All patients were operated on in a staged procedure and stent graft deployment was achieved. Procedural success was achieved in all cases. All patients were discharged with complete recovery. No endoleaks weres detected in further CT examination.</p><p><b>Conclusion:</b> Our results suggests that hybrid debranching and endovascular repair of extensive thoracoabdominal aneurysms represents a suitable therapeutic option to reduce the morbidity and mortality of TAAA repair, particularly in those typically considered at high risk for standard repair.</p>

EARLY RESULTS OF SINGLE-PORT LAPAROSCOPIC APPENDECTOMY

2017 ◽  
pp. 103-106
Author(s):  
Minh Duc Pham
Keyword(s):  
Laparoscopic Appendectomy ◽  
Single Port ◽  
Operation Time ◽  
Invasive Procedure ◽  
Minimal Invasive ◽  
University Hospital ◽  
Early Results ◽  
Sils Port ◽  
The Mean ◽  
A New Technique

Background: Conventional three–port laparoscopic appendectomy is becoming popular for the treatment of acute appendicitis. In this report, we present the early results of a new technique of laparoscopic appendectomy conducted through a single-port. Patients and Methods: From March 2011 to October 2013, we have performed 86 operations Single Port Laparoscopic Appendectomy at Hue University Hospital and Hue Central Hospital. SILS Port (Covidien) is used, it can be performed with basic laparoscopic instruments. Results: In this study, 86 patients underwent Single-Port laparoscopic appendectomy, among them 52.33% were femele, 47.67% were male, female/male ratio was 1.09. The mean age was 33.09. An orther trocar insertion was required in 2 patients (2.33%). The mean operation time was 42.03 minutes and mean postoperative hospital stay 3.37 days. Postoperative complication occurred in 2 case (2.33%) was of omphalitis. During 2 weeks follow up, 2 case (2.33%) was of omphalitis. Conclusions: Single - port intracorporeal appendectomy is a safe, minimal invasive procedure with excellent cosmetic results. Key words: Single Port Laparoscopic Appendectomy, appendectomy

scholarly journals Quantification of Measurement and Model Effects in Monopile Foundation Scour Protection Experiments

2021 ◽  
Vol 9 (6) ◽  
pp. 585
Author(s):  
Minghao Wu ◽  
Leen De Vos ◽  
Carlos Emilio Arboleda Chavez ◽  
Vasiliki Stratigaki ◽  
Maximilian Streicher ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Flow Field ◽  
Three Dimensional ◽  
Small Scale ◽  
Maximum Wave Height ◽  
Chaotic Flow ◽  
The Mean ◽  
Scour Protection ◽  
Damage Number ◽  
Measurement Effects

The present work introduces an analysis of the measurement and model effects that exist in monopile scour protection experiments with repeated small scale tests. The damage erosion is calculated using the three dimensional global damage number S3D and subarea damage number S3D,i. Results show that the standard deviation of the global damage number σ(S3D)=0.257 and is approximately 20% of the mean S3D, and the standard deviation of the subarea damage number σ(S3D,i)=0.42 which can be up to 33% of the mean S3D. The irreproducible maximum wave height, chaotic flow field and non-repeatable armour layer construction are regarded as the main reasons for the occurrence of strong model effects. The measurement effects are limited to σ(S3D)=0.039 and σ(S3D,i)=0.083, which are minor compared to the model effects.

Early results of micropulse transscleral cyclophotocoagulation for the treatment of glaucoma

2019 ◽  
Vol 30 (4) ◽  
pp. 700-705 ◽  
Author(s):  
Alexander T Nguyen ◽  
Jessica Maslin ◽  
Robert J Noecker
Keyword(s):  
Intraocular Pressure ◽  
Continuous Wave ◽  
Open Angle Glaucoma ◽  
Case Series ◽  
Angle Closure ◽  
Secondary Outcome ◽  
Early Results ◽  
Pressure Lowering ◽  
Transscleral Cyclophotocoagulation ◽  
The Mean

Purpose: To describe our clinical experience with the efficacy and safety of micropulse transscleral cyclophotocoagulation as a treatment for glaucoma. Methods: In this retrospective case series, we reviewed the charts of 95 consecutive patients with various glaucoma subtypes who underwent micropulse transscleral cyclophotocoagulation. Patients were offered micropulse transscleral cyclophotocoagulation if they had perimetric glaucoma refractory to intraocular pressure–lowering topical medications and who were poor candidates for traditional filtering surgery. Eligible patients were treated with the Micropulse P3 device (IQ 810 Laser Systems; Iridex, Mountain View, CA, USA) at 2.0–2.5 W for a duration of 90 s per hemisphere at a 31.3% duty cycle. If a retreatment was needed, the power was increased to up to 3.0 W with other parameters remaining the same. Patients were considered successfully treated if their intraocular pressure was lowered by at least 20% compared to their baseline. The main outcome measure was post-operative intraocular pressure; secondary outcome measures included the number of adverse events and complications that occurred with treatment. Results: The glaucoma subtypes treated included primary open-angle glaucoma (n = 51), exfoliation glaucoma (n = 24), chronic angle-closure glaucoma (n = 15), and congenital/juvenile glaucoma (n = 5). The mean pre-operative intraocular pressure was 25.1 ± 5.3 mm Hg and the mean post-operative intraocular pressure at 12 months was 17.5 ± 5.1 mm Hg (p = 0.004). The mean number of intraocular pressure–lowering medications used preoperatively was 3.0 ± 1.1; the mean number of medications used at the 12-month post-operative visit was 1.4 ± 1.0 (p = 0.03). Success with one treatment was achieved in 73 (76.8%) of patients. With multiple treatments, all patients had significant intraocular pressure–lowering compared to baseline. The maximum number of treatments received by any single patient was 5. There were no instances of prolonged intraocular inflammation or long-term hypotony. Conclusion: Micropulse transscleral cyclophotocoagulation appears to be a safe and efficacious treatment for glaucoma. Given its improved safety profile compared to continuous-wave transscleral cyclophotocoagulation, it deserves consideration as a primary procedure.

scholarly journals Roughness Lengths for Momentum and Heat Derived from Outdoor Urban Scale Models

2007 ◽  
Vol 46 (7) ◽  
pp. 1067-1079 ◽  
Author(s):  
M. Kanda ◽  
M. Kanega ◽  
T. Kawai ◽  
R. Moriwaki ◽  
H. Sugawara
Keyword(s):  
Wind Direction ◽  
Roughness Length ◽  
Scale Dependence ◽  
Scale Model ◽  
Small Scale ◽  
Physical Scale ◽  
Scale Models ◽  
Roughness Lengths ◽  
Urban Sites ◽  
Obstacle Height

Abstract Urban climate experimental results from the Comprehensive Outdoor Scale Model (COSMO) were used to estimate roughness lengths for momentum and heat. Two different physical scale models were used to investigate the scale dependence of the roughness lengths; the large scale model included an aligned array of 1.5-m concrete cubes, and the small scale model had a geometrically similar array of 0.15-m concrete cubes. Only turbulent data from the unstable boundary layers were considered. The roughness length for momentum relative to the obstacle height was dependent on wind direction, but the scale dependence was not evident. Estimated values agreed well with a conventional morphometric relationship. The logarithm of the roughness length for heat relative to the obstacle height depended on the scale but was insensitive to wind direction. COSMO data were used successfully to regress a theoretical relationship between κB−1, the logarithmic ratio of roughness length for momentum to heat, and Re*, the roughness Reynolds number. Values of κB−1 associated with Re* for three different urban sites from previous field experiments were intercompared. A surprising finding was that, even though surface geometry differed from site to site, the regressed function agreed with data from the three urban sites as well as with the COSMO data. Field data showed that κB−1 values decreased as the areal fraction of vegetation increased. The observed dependency of the bulk transfer coefficient on atmospheric stability in the COSMO data could be reproduced using the regressed function of Re* and κB−1, together with a Monin–Obukhov similarity framework.

scholarly journals Methodology for Developing Hydrological Models Based on an Artificial Neural Network to Establish an Early Warning System in Small Catchments

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Ivana Sušanj ◽  
Nevenka Ožanić ◽  
Ivan Marović
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Early Warning ◽  
Early Warning System ◽  
Warning System ◽  
Small Scale ◽  
Ann Model ◽  
Data Value ◽  
The Mean ◽  
Artificial Neural

In some situations, there is no possibility of hazard mitigation, especially if the hazard is induced by water. Thus, it is important to prevent consequences via an early warning system (EWS) to announce the possible occurrence of a hazard. The aim and objective of this paper are to investigate the possibility of implementing an EWS in a small-scale catchment and to develop a methodology for developing a hydrological prediction model based on an artificial neural network (ANN) as an essential part of the EWS. The methodology is implemented in the case study of the Slani Potok catchment, which is historically recognized as a hazard-prone area, by establishing continuous monitoring of meteorological and hydrological parameters to collect data for the training, validation, and evaluation of the prediction capabilities of the ANN model. The model is validated and evaluated by visual and common calculation approaches and a new evaluation for the assessment. This new evaluation is proposed based on the separation of the observed data into classes based on the mean data value and the percentages of classes above or below the mean data value as well as on the performance of the mean absolute error.

scholarly journals Early Results of Total Knee Arthroplasty with a Low Contact Stress Anteroposterior Glide

2009 ◽  
Vol 17 (2) ◽  
pp. 174-178 ◽  
Author(s):  
Adrian J Bauze ◽  
Mark S Falworth ◽  
Roger D Oakeshott
Keyword(s):  
Soft Tissue ◽  
Contact Stress ◽  
Cruciate Ligament ◽  
Valgus Deformity ◽  
Rotating Platform ◽  
Active Flexion ◽  
Early Results ◽  
Total Knee ◽  
The Mean ◽  
Low Contact Stress

Purpose. To present early results of 400 consecutive low contact stress (LCS) anteroposterior (AP) glide total knee arthroplasties (TKAs) performed by a single surgeon. Methods. 304 consecutive patients aged 30 to 96 (mean, 66) years underwent 400 TKAs using LCS AP glides performed by a single surgeon. Only patients with an intact posterior cruciate ligament, a fixed flexion deformity of <15°, and a valgus deformity of <15° were included. Patients were assessed pre- and post-operatively using the American Knee Society (AKS) and Hospital for Special Surgery (HSS) scores. Range of motion was measured using a goniometer. AP and lateral radiographs were assessed for radiolucencies and osteolysis. Results. The mean follow-up period was 4.2 (range, 1–8) years. The mean fixed flexion improved to 1° from 11° and the mean active flexion improved to 120° from 111°. Both AKS and HSS scores improved significantly. There were 28 anterior soft tissue impingements; 9 of them were in the first year of the study. Thereafter, the anterior lip of the bearing was modified and any offending osteophytes, soft tissue, or fat pads were excised. Of 39 (10%) knees that underwent re-operation (16 were due to anterior soft tissue impingement), 20 (5%) did not require change of the AP glide bearing and the remaining 19 were converted to a rotating platform bearing. No patellar baja was noted after fat pad excision. No patient had catastrophic wear or failure of the polyethylene bearing. The survival rate of the AP glide bearing was 95%. Conclusion. The early-to-mid-term outcomes of the LCS AP glide TKA are promising.

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