scholarly journals Biased Estimation of Groundwater Velocity from a Push-Pull Tracer Test Due to Plume Density and Pumping Rate

Water ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1558 ◽  
Author(s):  
Hong-Hyun Kim ◽  
Eun-Hee Koh ◽  
Seong-Sun Lee ◽  
Kang-Kun Lee
Keyword(s):  
Numerical Simulations ◽  
Drift Time ◽  
Tracer Tests ◽  
Tracer Test ◽  
Linear Velocity ◽  
Test Results ◽  
Groundwater Velocity ◽  
Pumping Rate ◽  
Laboratory Test Results ◽  
Pumping Rates

The single-well push-pull tracer test is a convenient and cost-effective tool to estimate hydrogeological properties of a subsurface aquifer system. However, it has a limitation that test results can be affected by various experimental designs. In this study, a series of laboratory-scale push-pull tracer tests were conducted under various conditions controlling input tracer density, pumping rate, drift time, and hydraulic gradient. Based on the laboratory test results, numerical simulations were performed to evaluate the effects of density-induced plume sinking and pumping rate on the proper estimation of groundwater background linear velocity. Laboratory tests and numerical simulations indicated that the actual linear velocity was underestimated for the higher concentration of the input tracer because solute travel distance and direction during drift time were dominantly affected by the plume density. During the pulling phase, reasonable pumping rates were needed to extract the majority of injected tracer mass to obtain a genuine center of mass time (tcom). This study presents a graph showing reasonable pumping rates for different combinations of plume density and background groundwater velocity. The results indicate that careful consideration must be given to the design and interpretation of push-pull tracer tests.

scholarly journals Groundwater circulation and earthquake-related changes in hydrogeological karst environments: a case study of the Sibillini Mountains (central Italy) involving artificial tracers

2020 ◽  
Vol 28 (7) ◽  
pp. 2409-2428 ◽  
Author(s):  
T. Nanni ◽  
P. M. Vivalda ◽  
S. Palpacelli ◽  
M. Marcellini ◽  
A. Tazioli
Keyword(s):  
Central Italy ◽  
Tracer Tests ◽  
Tracer Test ◽  
Breakthrough Curves ◽  
Water Circulation ◽  
Test Results ◽  
Flow Rates ◽  
Aquifer System ◽  
Structural Framework ◽  
Groundwater Circulation

Abstract Using artificial tracer tests, this study confirms the presence of a single basal aquifer feeding the springs in the wide and complex hydrogeological boundary of the Sibillini Mountains of central Italy. The tracer was introduced into the sinkhole of the Castelluccio di Norcia plain. The tracer test results, observed at the studied springs, highlight the changes induced by the 2016/2017 earthquake in the water circulation of the aquifer system. In particular, the seismic events increased the hydraulic conductivity of the basal aquifer, with a consequent increase in the springs’ flow rates at the western hydrogeological boundary and a decrease in the flow rates at the eastern Adriatic hydrogeological boundary. This phenomenon is in accordance with the hydro-structural framework of the area. The study also investigated the relation between groundwater circulation and tracer behaviour in the springs during the pre- and post-earthquake periods. The tracer test results led to the formulation of hypotheses about water circulation of the area. The trend of the tracer breakthrough curves demonstrates that the upper portion of the basal aquifer is characterised by fast water circulation similar to that in the epiphreatic area of karst aquifers, while a slow circulation due to fissures with interconnected drains occurs in the deepest portion of the aquifers. The obtained results highlight how tectonics and karst can affect the hydrogeological setting of the Apennine carbonate chain; in particular, the seismicity of central Italy may alter groundwater circulation for a long period of time when great magnitude earthquakes occur.

Mixing and Detention Time Distribution in Activated Sludge Tanks

1985 ◽  
Vol 17 (2-3) ◽  
pp. 197-208 ◽  
Author(s):  
H. Bode ◽  
C. F. Seyfried
Keyword(s):  
Activated Sludge ◽  
Time Distribution ◽  
Strong Influence ◽  
Tracer Tests ◽  
Tracer Test ◽  
Evaluation Procedure ◽  
Response Curves ◽  
Detention Time ◽  
Test Study ◽  
Mixing Characteristics

The interrelationship between mixing characteristics and tracer response curves in activated sludge tanks is explained. In some cases the return sludge cycle has a strong influence on the tracer response curves. Results from tracer tests in the field are hard to interpret because the tracer in the return sludge interferes with the initial tracer. Therefore a special evaluation procedure has to be applied. The paper closes with results from a field tracer test study.

Effect of Ibuprofen on Serum Laboratory Test Results

1983 ◽  
Vol 40 (6) ◽  
pp. 1025-1034
Author(s):  
Carol L. Colvin ◽  
Raymond J. Townsend ◽  
William R. Gillespie ◽  
Kenneth S. Albert
Keyword(s):  
Laboratory Test ◽  
Test Results ◽  
Laboratory Test Results

Quality benchmarking of smartphone laboratory medicine applications: comparison of laboratory medicine specialists’ and non-laboratory medicine professionals’ evaluation

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Snežana Jovičić ◽  
Joanna Siodmiak ◽  
Marta Duque Alcorta ◽  
Maximillian Kittel ◽  
Wytze Oosterhuis ◽  
...  
Keyword(s):  
Information Quality ◽  
Rating Scale ◽  
Laboratory Medicine ◽  
Test Results ◽  
Content Quality ◽  
Laboratory Test Results ◽  
System Usability Scale ◽  
Mobile Health Applications ◽  
Fit For Purpose ◽  
Health Applications

AbstractObjectivesThere are many mobile health applications (apps) now available and some that use in some way laboratory medicine data. Among them, patient-oriented are of the lowest content quality. The aim of this study was to compare the opinions of non-laboratory medicine professionals (NLMP) with those of laboratory medicine specialists (LMS) and define the benchmarks for quality assessment of laboratory medicine apps.MethodsTwenty-five volunteers from six European countries evaluated 16 selected patient-oriented apps. Participants were 20–60 years old, 44% were females, with different educational degrees, and no professional involvement in laboratory medicine. Each participant completed a questionnaire based on the Mobile Application Rating Scale (MARS) and the System Usability Scale, as previously used for rating the app quality by LMS. The responses from the two groups were compared using the Mann-Whitney U test and Spearman correlation.ResultsThe median total score of NLMP app evaluation was 2.73 out of 5 (IQR 0.95) compared to 3.78 (IQR 1.05) by the LMS. All scores were statistically significantly lower in the NLMP group (p<0.05), except for the item Information quality (p=0.1631). The suggested benchmarks for a useful appear: increasing awareness of the importance and delivering an understanding of persons’ own laboratory test results; understandable terminology; easy to use; appropriate graphic design, and trustworthy information.ConclusionsNLMP’ evaluation confirmed the low utility of currently available laboratory medicine apps. A reliable app should contain trustworthy and understandable information. The appearance of an app should be fit for purpose and easy to use.

scholarly journals COVID-19 and pregnancy – where are we now? A review

2020 ◽  
Vol 48 (5) ◽  
pp. 428-434 ◽  
Author(s):  
Aleksandra Rajewska ◽  
Wioletta Mikołajek-Bedner ◽  
Joanna Lebdowicz-Knul ◽  
Małgorzata Sokołowska ◽  
Sebastian Kwiatkowski ◽  
...  
Keyword(s):  
Case Fatality ◽  
Fetal Distress ◽  
Delivery Mode ◽  
Test Results ◽  
Rt Pcr ◽  
Third Trimester ◽  
The Third ◽  
Laboratory Test Results ◽  
Protective Antibodies ◽  
Polymerase Chain

AbstractThe new acute respiratory disease severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is highly contagious. It has caused many deaths, despite a relatively low general case fatality rate (CFR). The most common early manifestations of infection are fever, cough, fatigue and myalgia. The diagnosis is based on the exposure history, clinical manifestation, laboratory test results, chest computed tomography (CT) findings and a positive reverse transcription-polymerase chain reaction (RT-PCR) result for coronavirus disease 2019 (COVID-19). The effect of SARS-CoV-2 on pregnancy is not already clear. There is no evidence that pregnant women are more susceptible than the general population. In the third trimester, COVID-19 can cause premature rupture of membranes, premature labour and fetal distress. There are no data on complications of SARS-CoV-2 infection before the third trimester. COVID-19 infection is an indication for delivery if necessary to improve maternal oxygenation. Decision on delivery mode should be individualised. Vertical transmission of coronavirus from the pregnant woman to the fetus has not been proven. As the virus is absent in breast milk, the experts encourage breastfeeding for neonatal acquisition of protective antibodies.

scholarly journals Atypical anti-glomerular basement membrane disease with anti-GBM antibody negativity and ANCA positivity: a case report

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Na Guo ◽  
Qinghua Yin ◽  
Song Lei ◽  
Yanjun He ◽  
Ping Fu
Keyword(s):  
Basement Membrane ◽  
Glomerular Basement Membrane ◽  
Rare Case ◽  
Test Results ◽  
Serum Samples ◽  
Tissue Samples ◽  
Case Presentation ◽  
Severe Renal Insufficiency ◽  
Laboratory Test Results ◽  
Organ Specific

Abstract Background Anti-glomerular basement membrane (anti-GBM) disease is an organ-specific autoimmune disease that involves the lung and kidneys and leads to rapid glomerulonephritis progression, with or without diffuse alveolar hemorrhage, and even respiratory failure. Classic cases of anti-GBM disease are diagnosed based on the presence of the anti-GBM antibody in serum samples and kidney or lung biopsy tissue samples. However, atypical cases of anti-GBM disease are also seen in clinical practice. Case presentation We herein report the rare case of a patient with atypical anti-GBM disease whose serum was negative for the anti-GBM antibody but positive for the myeloperoxidase (MPO) anti-neutrophil cytoplasmic antibody (p-ANCA) and another atypical ANCA. Laboratory test results showed severe renal insufficiency with a creatinine level of 385 μmol/L. Renal biopsy specimen analysis revealed 100% glomeruli with crescents; immunofluorescence showed immunoglobulin G (IgG) linearly deposited alongside the GBM. Finally, the patient was discharged successfully after treatment with plasmapheresis, methylprednisolone and prednisone. Conclusion This patient, whose serum was negative for the anti-GBM antibody but positive for p-ANCA and another atypical ANCA, had a rare case of anti-GBM disease. Insights from this unusual case might help physicians diagnose rare forms of glomerulonephritis and treat affected patients in a timely manner.

scholarly journals Experimental Study of the Space–Time Effect of a Double-Pipe Frozen Curtain Formation with Different Groundwater Velocities

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3830
Author(s):  
Shicheng Sun ◽  
Chuanxin Rong ◽  
Hua Cheng ◽  
Bin Wang ◽  
Xiaogang Jiang ◽  
...  
Keyword(s):  
Freezing Temperature ◽  
Physical Model Test ◽  
Sand Layer ◽  
Test Results ◽  
Groundwater Velocity ◽  
Test Platform ◽  
The Difference ◽  
Freezing Test ◽  
Double Pipe ◽  
Thermal Physical Properties

Groundwater velocity has significant effects on the formation of a frozen curtain during freezing. In order to study the influence of the velocity on a frozen curtain, a large physical model test platform was established for double-pipe freezing. Based on this platform, freezing tests for different velocities were carried out. Quartz sand was selected as a similar material. The freezing temperature of the saturated sand layer was found by analyzing the results of the nuclear magnetic resonance (NMR). Based on the study of the thermal physical properties of the sand layer, the freezing test results were analyzed, and the results showed that the flow led to the differential development of the temperature between the upstream and downstream sections of the freezing pipes. Moreover, the larger the velocity, the greater the difference. The flow prolonged the overlapping time of the frozen curtains. Additionally, the flow slowed down the development of the frozen curtain area and the frozen curtain thickness. The larger the flow velocity, the greater the inhibition of the flow on the development of the frozen curtain. The test results can provide more references for the design and construction of freezing engineering with flowing groundwater.

Requiem for the STAT Test: Automation and Point of Care Testing

2019 ◽  
Author(s):  
Gurmukh Singh ◽  
Natasha M Savage ◽  
Brandy Gunsolus ◽  
Kellie A Foss
Keyword(s):  
Point Of Care ◽  
Turnaround Time ◽  
Test Automation ◽  
Test Results ◽  
Point Of Care Testing ◽  
Tube System ◽  
Front End ◽  
Laboratory Test Results ◽  
Batch Testing ◽  
Pneumatic Tube System

Abstract Objective Quick turnaround of laboratory test results is needed for medical and administrative reasons. Historically, laboratory tests have been requested as routine or STAT. With a few exceptions, a total turnaround time of 90 minutes has been the usually acceptable turnaround time for STAT tests. Methods We implemented front-end automation and autoverification and eliminated batch testing for routine tests. We instituted on-site intraoperative testing for selected analytes and employed point of care (POC) testing judiciously. The pneumatic tube system for specimen transport was expanded. Results The in-laboratory turnaround time was reduced to 45 minutes for more than 90% of tests that could reasonably be ordered STAT. With rare exceptions, the laboratory no longer differentiates between routine and STAT testing. Having a single queue for all tests has improved the efficiency of the laboratory. Conclusion It has been recognized in manufacturing that batch processing and having multiple queues for products are inefficient. The same principles were applied to laboratory testing, which resulted in improvement in operational efficiency and elimination of STAT tests. We propose that the target for in-laboratory turnaround time for STAT tests, if not all tests, be 45 minutes or less for more than 90% of specimens.

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