Elasticity and damping ratio measurement of droplets on super-hydrophobic surfaces

The measurement of the droplets’ elasticity is vitally important in microfluidic and ink-jet printing. It refers to the ability of the droplet to restore its original shape and strong robustness. This study investigated a novel method to measure elasticity. The plate coated with super-hydrophobic layers pressed on a droplet and the elastic force was recorded by an electronic balance. Meanwhile, a mathematical model was constructed to calculate the changes of the droplet area under the force. The measurement showed that external work mainly converts into surface energy and the damping ratio increases from 0.068 to 0.261 with the increase of mass fraction from 0 to 80 wt%. It also indicates that the novel method can accurately and efficiently measure the elasticity of droplets.

A Clinical Evaluation Study of Cardiothoracic Ratio Measurement Using Artificial Intelligence

Background Artificial Intelligence, particularly the Deep Learning (DL) model, can provide reliable results for automated cardiothoracic ratio (CTR) measurement on Chest x-ray (CXR) images. In everyday clinical use, however, this technology is usually implemented in a non-automated (AI-assisted) capacity because it still requires approval from radiologists. We investigated the performance and efficiency of our recently proposed models for the AI-assisted method intended for clinical practice. Methods We validated four proposed DL models (AlbuNet, SegNet, VGG-11, and VGG-16) to find the best model for clinical implementation using a dataset of 7,517 CXR images from manual operations. These models were investigated in single-model and combined-model modes to find the model with the highest percentage of results where the user could accept the results without further interaction (excellent grade), and with measurement variation within ± 1.8% of the human-operating range. The best model from the validation study was then tested on an evaluation dataset of 9,386 CXR images using the AI-assisted method with two radiologists to measure the yield of excellent grade results, observer variation, and operating time. A Bland-Altman plot with coefficient of variation (CV) was employed to evaluate agreement between measurements. Results The VGG-16 gave the highest excellent grade result (68.9%) of any single-model mode with a CV comparable to manual operation (2.12% vs 2.13%). No DL model produced a failure-grade result. The combined-model mode of AlbuNet+VGG-11 model yielded excellent grades in 82.7% of images and a CV of 1.36%. Using the evaluation dataset, the AlbuNet+VGG-11 model produced excellent grade results in 77.8% of images, a CV of 1.55%, and reduced operating time by almost ten-fold (1.07 ± 2.62 secs vs 10.6 ± 1.5 sec) compared to manual operation. Conclusion Due to its exceptional accuracy and speed, the AlbuNet+VGG-11 model could be clinically implemented to assist radiologists with CTR measurement.

735 Myocardial ischaemia: not just about obstructive coronary arteries

Aims A vast proportion of subjects with anginal symptoms undergoing invasive coronary angiography (ICA) suffer from ischaemia with non-obstructive coronary arteries (INOCA). This condition has many contributing mechanisms, including epicardial vasospasm caused by vasomotor disorder, which is characterized by ST-segment changes during the self-limiting chest pain episodes. The diagnosis of this condition is challenging. Although different provocative test could performed during ICA (e.g. intracoronary administration of acetylcholine or ergonovine), their use is uncommon. Methods and results Clinical case A 39-years old man, smoker, hypertensive and dyslipidemic, presented to the emergency department after a Holter dynamic ECG detecting transient ST-segment elevation in the D1 lead. He had recurrent rest angina despite medical therapy and a prior ICA performed one year before the current presentation documented a mild stenosis of the posterior descending artery, a moderate stenosis of a duplicated left anterior descending artery, and a chronic total occlusion of the left obtuse marginal, which was not revascularized because of the absence of inducible ischaemia on single-photon emission computed tomography. The new ICA performed at presentation revealed a significant progression of coronary artery disease at the level of the posterior descending artery, which was treated through percutaneous coronary intervention, while the other vessels were unchanged. During the procedure, the patient experienced severe angina with ST-segment elevation and angiographically evident vasospasm of left coronary artery. The instantaneous wave-free ratio measurement performed on the medial branch of the duplicated left anterior descending artery was 0.86, which quickly resolved after administration of nitrate (0.93). Calcium channel blockers were added to medical therapy and the patient was discharged asymptomatic. Conclusions Vasospastic angina can cause ischaemia both in the presence and in the absence of visible atherosclerosis. This cause of INOCA often remains undetected but it is relatively frequent especially among younger patients who continue experiencing angina leading to repeated hospitalizations. The chance of this condition should be always taken into account, and the correct diagnosis should be obtained not incidentally like in the present case, but following standardized intracoronary test in a proper setting.

Investigation and Interpretation of Maximal and Reactive Strength Index Characteristics of 16-17 Age Group Basketball Players

Aim: The aim of the study was determined as the examination of the reactive strength index parameter, which shows the maximal strength and explosive force characteristics of 16-17 age group basketball players determined by isometric test. Method: The basketball branch Xage = 16.50 ± 0.51 years, XHeight = 177.22 ± 8,56 cm, XBW= 73.14 ± 12,43 kg, XBMI= 23.26 ± 3,46 kg / m2, and XBFP = 14.72 ± 5.67% of which 32 are men. In the study, the measurements of the height of the participants were made with Holtain brand stadiometer, body weight and fat percentage ratio measurement with Tanita BC 418 MA, reactive strength index measurement with Opto Jump Next, and maximal strength measurement with Baseline brand leg dynamometers. Pearson test was used to determine the relationship between branch-specific MS and RSI. Results: According to the correlation results, no significant relationship was found between MS and RSI (p>0.05). Conclusions: As a result, it has been determined that basketball players between the ages of 16-17 do less quality work on developing MS and explosive force. Keywords: Basketball, Maximal Strength, Reactive Strength İndex.

1 X 1000 kVA Transformer Measurement Analysis using Dyn-11 Vector Group and Off Load Tap Changer

The transmission line of electrical energy generated by the power plant is usually located far from the load center to be distributed to the community. The substation is part of a distribution transmission line that acts as a control center and consists of a collection of extra high voltage equipment. Routine maintenance of the power transformer as the main equipment of the substation must be scheduled so that its performance remains reliable. The proposed method of this research is to analyze the condition of the transformer through testing when it is off, to the calculation of the transformer ratio to determine the condition of the transformer windings using the calculation of the formula and measurement of the Raytech Transformer Turn Ration measuring instrument. In this research, the Raytech Transformer Turn Ratio measurement tool is used to determine the ratio of the winding input voltage of 20,000 volts and the output voltage of 400 volts on the power transformer. At a voltage of 40VAC, from the results of the comparisons that have been made, it can be seen that the test results of the Raytech Transformer Turn Ratio measuring instrument, if it crosses the 0.5% tolerance limit, the measurement results on one of the coils change the ratio. If the transformer is not regularly checked, the impact will result in unbalance of voltage on one of the coils. And one of the coils in phase will expand and cause a loss of voltage.

Cerebroplacental Ratio on Doppler as a Predictor of Fetuses at Risk of Perinatal Complications

Background: Doppler velocimetry is the best method of surveillance for fetal hypoxemia during pregnancy. Cerebroplacental ratio (CPR), has been suggested as a useful clinical simplification. It is believed that the CPR better predicts adverse perinatal outcomes than its individual components and better than conventional anthropometric models. Therefore, the aim of this study is to evaluate the significance of the cerebroplacental 10th centile threshold measured weekly from 36 weeks of gestation till delivery as a screening test for prediction of need for Cesarean section for intrapartum fetal compromise and the adverse neonatal outcome in women with normally grown fetuses and uncomplicated pregnancy. Methods: This study was carried out on 40 pregnant women uncomplicated, singleton pregnancy with appropriately grown fetuses on clinical assessment. The last Doppler indices including cerebroplacental ratio measurement obtained before labor was reported. CPR values below 1.1 were reported as abnormal. Various studies have variably defined the threshold of abnormal CPR ratio as <1.08. Results: There was significant decrease in the Mean of CPR among patients who had anemia compared to those without anemia. In addition, there was no significant association seen between low CPR and having previous history of abortion or IUGR as well as being a smoker. There was no significant difference between cases who had normal and abnormal CPR regarding gestational age at delivery. There was no difference between cases who had normal and abnormal cerebroplacental ratio regarding mode of delivery. there was significant decrease in the prevalence of low birth weight among group who had CPR≥1.08. CPR <1.08 was significantly associated with neonatal complication like NICU admission, and neonatal death. There was no statistically significant relationship between cerebroplacental ratio and neonatal complication like IUFD, and neonatal sepsis. There was no statistically significant association between the mean cerebroplacental ratio and IUFD. There was statistically significant association between the mean cerebroplacental ratio and NICU. There was no statistically significant association between the mean cerebroplacental ratio and neonatal sepsis. The mean cerebroplacental ratio of 0.93± 0.22 has a significant association with neonatal death. Conclusion: A low cerebroplacental ratio reflects redistribution of the cardiac output to the cerebral circulation and has been shown to improve accuracy in predicting adverse outcome compared with Middle cerebral artery (MCA) or Umbilical artery (UA) Doppler alone. Therefore, integrating CPR in clinical management may help to better identify fetuses at risk for adverse perinatal events, since abnormal CPR has been associated with an increased risk of perinatal complications.

Aircraft measurements of water vapor heavy isotope ratios in the marine boundary layer and lower troposphere during ORACLES

This paper presents the water vapor heavy isotope ratio measurement system developed for aircraft in-situ measurements and used in the NASA ObseRvations of Aerosols above CLouds and their intEractionS (ORACLES) project. The resultant dataset collected, which includes measurements of specific humidity and the heavy isotope ratios D / H and 18O / 16O, is also presented. Aircraft sampling took place in the southeast Atlantic marine boundary layer and lower troposphere (equator to 22° S) over the months of Sept. 2016, Aug. 2017, and Oct. 2018. Isotope measurements were made using cavity ring-down spectroscopic analyzers integrated into the Water Isotope System for Precipitation and Entrainment Research (WISPER). The water concentration and isotopic data accompanied a suite of other variables including standard meteorological quantities (wind, temperature, moisture), trace gas and aerosol concentrations, radar, and lidar remote sensing. From an isotope perspective, the 300+ hours of 1 Hz in-situ data at levels in the atmosphere ranging from 70 m to 6 km represents a remarkably large and vertically resolved dataset. This paper provides a brief overview of the ORACLES mission and describes how water vapor heavy isotope ratios fit within the experimental design. Overviews of the sampling region and WISPER system setup are presented, along with calibration details, measurement uncertainties, and suggested data usage. Characteristics in the spatial variability of the study region over the three sampling periods are highlighted with latitude-altitude curtains. A number of individual tropospheric profiles are presented to illustrate the fidelity with which a series of different hydrologic processes are captured by the observations. The curtains and profiles demonstrate the dataset’s potential to provide a comprehensive perspective on moisture transport and isotopic content in this region. Readers interested in a quick reference to data usage and uncertainty estimation can consult the beginning of section 5. Data for the Sept. 2016, Aug. 2017, and Oct. 2018 sampling periods can be accessed at https://doi.org/10.5067/Suborbital/ORACLES/P3/2016_V2, https://doi.org/10.5067/Suborbital/ORACLES/P3/2017_V2, and https://doi.org/10.5067/Suborbital/ORACLES/P3/2018_V2, respectively (see references for ORACLES Science Team, 2020 – 2016 P3 data, 2017 P3 data, and 2018 P3 data).

Quantifying image quality in chest computed tomography angiography: Evaluation of different contrast-to-noise ratio measurement methods

Background Contrast-to-noise ratio is used to objectively evaluate image quality in chest computed tomography angiography (CTA). Different authors define and measure contrast-to-noise ratio using different methods. Purpose To summarize and evaluate the different contrast-to-noise ratio calculation formulas in the current literature. Material and Methods A systematic review of the recent literature for studies using contrast-to-noise ratio was performed. Contrast-to-noise ratio measurement methods reported by the different authors were recorded and reproduced in three patients who underwent chest CTA in our department for exploring variations among the different measurement methods. Results The search resulted in 109 articles, of which 26 were included. The studies involved 69 different measurements and overall, three different formula patterns. In all three, aorta and pulmonary arteries comprised the objects of interest in the numerator. In the denominator, standard deviation of the attenuation of the object of interest itself or of another background were used to reflect image noise. Some authors averaged the ratio values at different levels to obtain global ratio values. Using the object of interest itself for image noise calculation in the denominator compared to the usage of another background caused the most prominent variances of contrast-to-noise ratio between the two different protocols used for the reproduction of the measurements. Conclusion We recommend using the standard deviation of the attenuation of a background indicator as image noise rather than the object of interest itself for more reliable and comparative values. Global contrast-to-noise ratios based on averaging the values of different measurement levels should be avoided.