Frost formation through super-cooled water within micron gap of galvanic coupled arrays.

Frost is considered one of the key factors that negatively affects numerous daily life aspects all over the globe such as growth of crops, safety of aviation and transportation vehicles, working efficiency of air circulating systems and many others. Therefore, monitoring and early detection of frost are crucially needed to avoid such drastic effects. In this study, we used the micron gap of our newly developed galvanic coupled arrays named as moisture sensor chip (MSC) for the early detection of frost formation from super-cooled water droplets. The early frost formation was monitored via the tiny ice crystals formed on the cooled MSC surface at four different humidity levels using simultaneous electrochemical and optical microscopic detection tools. Experimental results revealed for the first time a remarkable increase in the detected galvanic current due to the condensation frosting mechanism of super-cooled water droplets via liquid transition transformation even at very low relative humidity which was believed to be responsible for de-sublimation frosting. Moreover, the super-cooled droplets formed ice bridges along their boundary domains due to the accumulation of the acquired water vapour that was evidenced by the release of the heat of solidification. These findings demonstrated that the MSC could be used as a promising platform for the early detection of frost formation considering the appropriate protective measures against its adverse effects.

Quantitative Correlation of Droplets on Galvanic-Coupled Arrays with Response Current by Image Processing.

Evaluating the presence of a slight amount of water plays a crucial role in practical applications such as the advanced detection of dew condensation and the microdetermination of perspiration and transpiration. For this purpose, we have developed a configuration for the moisture sensor that consists of a microgalvanic cell composed of narrow metal arrays. It is inferred that the output response current arising from this sensor should depend on the geometric parameters (e.g., number, area, volume, etc.) of water droplets attaching on the sensor surface. In this study, the output current was recorded, while the microscopic images of the sensor surface were captured. The droplets on the sensor surface were analyzed manually and by computational image processing with deep learning and ImageJ. The deep learning technique shortened the processing time to 1/1000 of the manual one and was able to match 90-100% of the manual count. The results revealed that the response current increased with the total projected area of droplets bridging the galvanic-coupled arrays on the sensor surface. In addition, a straight line with relatively strong positive correlation was obtained between the response current and the total volume of the bridging droplets. These findings suggested that our sensor can be practically used to estimate the presence of a slight amount of water.

Quick and Sensitive Detection of Water Using Galvanic-Coupled Arrays with a Submicron Gap for the Advanced Prediction of Dew Condensation.

We have demonstrated a highly sensitive moisture sensor that can detect water molecules, in addition to water droplets, and therefore, can predict dew condensation with high accuracy and high speed before the formation of water droplets, showing a better performance than a commercial hygrometer. Additionally, the dependence of the output response from the sensor on factors, such as the cooling rate of the sensor's surface and the vapor pressure in the chamber, that affect the performance of the moisture sensor has been clarified. The output response showed a clear dependence on the variation in cooling rate, as well as the vapor pressure. The higher the cooling rate and vapor pressure, the higher the output response. The output response showed a linear response to the change in the above-mentioned parameters. The higher sensitivity and accuracy of the moisture sensor, as a function of the physical parameters, such as cooling rates, vapor pressure, enables the sensor to perform in advanced detection applications. The sensor can be modified to the actual target regarding the surface nature and the heat capacity of the target object, making it more suitable for wide applications.

Enhancement of Sensitivity and Accuracy of Micro/Nano Water Droplets Detection Using Galvanic-Coupled Arrays.

A moisture sensor has been reported that detects invisibly small water droplets and distinguishes their particle size with high accuracy and high speed. This sensor uses narrow lines of dissimilar metals as electrodes, arranged with gaps of 0.5 to 10 µm. The working principle for this sensor is that it measures the galvanic current generated when a water droplet forms a bridge-like structure between the electrodes. In addition, the surface of the sensor was controlled by using hydrophilic polymer, GL, and hydrophobic polymer, PMMA. The study of the relationship between the contact angle, projected area of water droplets and current response from the sensor with a modified surface showed that in the case of GL, the contact angle was small (wettability increased) and the average value and distribution of the projected water droplet area and the sensor's response increased. This enhanced the sensor's sensitivity. On the other hand, in the case of PMMA, the contact angle was large (wettability decreased), the area of the water droplet and its distribution became small and the accuracy of discriminating the water droplet's diameter by the sensor enhanced. Therefore, by rendering sensor's surface hydrophilic and hydrophobic, the sensitivity and accuracy of the sensor could be enhanced.

Ongoing allergic rhinitis impairs asthma control by enhancing the lower airway inflammation.

BACKGROUND: The relationship between allergic rhinitis and asthma is well accepted; however, little is known about the mechanism that underlies the interactions between the upper and lower airways. OBJECTIVE: To investigate the symptomatic and inflammatory linkages between allergic rhinitis and asthma in patients with atopy. METHODS: We enrolled 520 patients with asthma who were taking inhaled corticosteroids, and examined them by using the Asthma Control Questionnaire, spirometry, exhaled nitric oxide fraction (FENO), visual analog scale for nasal symptoms, allergic rhinitis questionnaire, and serum specific IgE (study 1). The symptomatic and inflammatory marker responses to nasal corticosteroids in patients with incompletely controlled asthma (Asthma Control Questionnaire > 0.75) and moderate-to-severe persistent allergic rhinitis were also observed (study 2). RESULTS: A total of 348 patients (66.9%) had atopy and allergic rhinitis. There was a striking difference in the proportion of patients with incomplete asthma control, depending on the presence as well as the activity of rhinitis (no rhinitis, 11.0%; mild intermittent, 20.4%; moderate-to-severe intermittent, 44.6%; mild persistent, 53.1%; moderate-to-severe persistent, 65.7%). The FENO levels were increased with the activity of rhinitis, and the nasal visual analog scale was positively correlated with the FENO levels (r = 0.31; P < .0001). The additive treatment with nasal corticosteroids improved the nasal visual analog scale, Asthma Control Questionnaire, and FENO levels, and the changes in these variables were correlated with each other in all parameters (all P < .001). CONCLUSION: This observational study of patients with atopy indicates that the ongoing allergic rhinitis is related to worsening of asthma by enhancing the lower airway inflammation.

[A case of mediastinal pancreatic pseudocyst with hemoptysis successfully treated with total parenteral nutrition].

A 51-year-old man with chronic alcohol-related pancreatitis was admitted to our hospital complaining of hemoptysis. A chest X-ray film revealed a ground-glass opacity in the left lower lung field and a bronchoscopic examination revealed bleeding from the left lower lobe bronchus. Chest multi detector-row CT demonstrated a cystic mediastinal mass along the esophagus from the pancreatic tail reaching the carina. No pleural effusion was found. Based on the clinical and radiographic features, we diagnosed mediastinal pancreatic pseudocyst. After four weeks of the treatment of pancreatitis with total parenteral nutrition, hemoptysis was disappeared and the serum amylase level normalyzed. The follow-up CT scan showed that the cystic mediastinal mass had disappeared completely. Mediastinal pancreatic pseudocyst accompanied by hemoptysis is very rare. We suggest that mediastinal pancreatic pseudocyst also should be considered in the differential diagnosis of alcoholics with hemoptysis.

[Spontaneous resolution of Pneumocystis carinii pneumonia].

A 58-year-old woman was admitted to our hospital complaining of fever, dry cough, and exertional dyspnea. Chest radiographs showed diffuse interstitial infiltrates in both lungs, and blood gas analysis showed moderate hypoxemia. The levels of serum KL-6 and beta-D-glucan were markedly elevated. Bronchoscopy was performed and Pneumocystis carinii was found in the BALF and transbronchial lung biopsy specimens. A positive reaction for the HTLV-I antibody was obtained, and HTLV-I proviral DNA was demonstrated. A conclusive diagnosis of Pneumocystis carinii pneumonia in a smoldering ATL patient was made on these grounds. Without specific treatment for Pneumocystis carinii pneumonia, the symptoms and abnormal chest radiographic findings disappeared. This case suggests that the fluctuation in cell-mediated immunity associated with HTLV-I carriers may allow recovery from Pneumocystis carinii pneumonia even without antipneumocystis therapy.