Summary
The purpose of this study was to help provide data to help to implement effective rehabilitation following surgery for oral cancer by comparing tongue pressure production for water and ...thickened water from the anterior and posterior parts of the tongue during swallowing. Ten healthy volunteers (7 men, 3 women; age 27.6 ± 1.5 years) participated in the experiments. Tongue pressure during 3 mL water and 3 mL thickened water at the anterior and posterior tongue during swallowing was measured using a sensor sheet system with five measuring points on the hard palate. The sequential order of the points, maximal magnitude and duration of tongue pressure at each point were compared based on water viscosity and tongue ingestion site. There was a common pattern in the sequential order of tongue pressure generation among the two swallowing conditions. The maximal magnitude of tongue pressure was significantly higher when swallowing thickened water than when swallowing water at all points except for the anterior‐median and mid‐median part. Moreover, the pressure at all sites during posterior ingestions was significantly lower than that during anterior ingestion. The present results provide mean values of tongue pressure during voluntarily triggered swallowing in anterior ingestion and posterior ingestion in young, healthy dentate individuals; these values can be clinically referenced for tongue pressure measurement in the evaluation of patients with dysphagia. The use of reference values may help streamline the diagnosis, treatment and rehabilitation of dysphagia.
Global Lightning and Sprite Measurements on Japanese Experiment Module (JEM‐GLIMS) is a space mission to conduct the nadir observations of lightning discharges and transient luminous events (TLEs). ...The main objectives of this mission are to identify the horizontal distribution of TLEs and to solve the occurrence conditions determining the spatial distribution. JEM‐GLIMS was successfully launched and started continuous nadir observations in 2012. The global distribution of the detected lightning events shows that most of the events occurred over continental regions in the local summer hemisphere. In some events, strong far‐ultraviolet emissions have been simultaneously detected with N2 1P and 2P emissions by the spectrophotometers, which strongly suggest the occurrence of TLEs. Especially, in some of these events, no significant optical emission was measured by the narrowband filter camera, which suggests the occurrence of elves, not sprites. The VLF receiver also succeeded in detecting lightning whistlers, which show clear falling‐tone frequency dispersion. Based on the optical data, the time delay from the detected lightning emission to the whistlers was identified as ∼10 ms, which can be reasonably explained by the wave propagation with the group velocity of whistlers. The VHF interferometer conducted the spaceborne interferometric observations and succeeded in detecting VHF pulses. We observed that the VHF pulses are likely to be excited by the lightning discharge possibly related with in‐cloud discharges and measured with the JEM‐GLIMS optical instruments. Thus, JEM‐GLIMS provides the first full set of optical and electromagnetic data of lightning and TLEs obtained by nadir observations from space.
Key Points
JEM‐GLIMS started continuous nadir observations of lightning and TLEs from ISS
Optical instruments succeeded in characterizing lightning and TLE emissions
Properties of lightning discharges exciting VHF pulses were first identified
We fabricated a coplanar waveguide (CPW) using high temperature superconductor YBa2Cu3O7-δ (YBCO) and evaluated its characteristics for the realization of a superconducting parametric amplifier. A ...YBCO thin film with a film thickness of 200 nm was formed by the PLD method using a YAG laser on a 10 × 10 mm MgO substrate. The YBCO thin films were processed into the CPW shape with a line width of 8 μm, a gap width of 8 μm and a line length of 5 mm by photolithography and sputter etching. Using a network analyzer, phase differences of microwave were measured at dc current bias from 0 mA to 14 mA. From the measurement results, it was found that the phase difference decreased with increasing temperature. In addition, it was found that the phase shifts greatly varied near the superconducting transition temperature at each current bias. We observed a maximum phase difference Δθ of -0.08 rad at a bias current of 14.0 mA, which is the closest to the transition temperature. A parametric gain was estimated to be 0.15 dB from the measured maximum phase difference.
Summary
We developed a barometer applicable to a small space, to assess oral and pharyngeal functions. Negative oral pressure during rest and pressure changes during swallowing were measured in a ...space between the palate and tongue (STP). Twenty volunteers were asked to sit in a chair in a relaxed upright position. A sensor was placed on the posterior midline of hard palate. Recording commenced just before subjects closed their lips and continued. Subjects were asked to swallow saliva and keep the apposition. Finally, subjects were asked to open their mouth. Recordings were performed five times, and 5 s of continuous data in each phase was averaged. To verify the reliability of the system, the same procedure was accomplished with twin sensors. When the jaw and lips were closed, the pressure slightly decreased from atmospheric pressure (−0·17 ± 0·24‐kPa). After swallowing, the pressure in STP showed more negative value (−0·50 ± 0·59‐kPa). There is a significant difference between the values in open condition and after swallowing (P < 0·001) and between values after swallowing and final open condition (P < 0·05). Twin sensor showed almost the same trajectories of pressure changes for all the recordings. Obtained negative pressure might generate about 0·71‐N of force and would be enough to keep the tongue in the palatal fossa at rest. The system detected large negative/positive pressure changes during swallowing. We conclude this system may be a tool to evaluate oral functions.
As shown in our previous study, inspiration after swallowing (SW-I) increases during the bi-level positive airway pressure ventilation (BiPAP) in healthy subjects because swallowing-associated ...non-inspiratory flow (SNIF) triggers inspiratory support, while SW-I during continuous positive pressure ventilation (CPAP) is rare. In the present study, we evaluated the coordination between breathing and swallowing during spontaneous breathing, BiPAP, and CPAP in patients with chronic obstructive pulmonary disease (COPD).
This study is a prospective intervention study at the Hoshigaoka Medical Center (November 01, 2015-April 30, 2018). We simultaneously recorded the respiratory flow, laryngeal motion, and swallowing sounds during saliva swallowing in patients with COPD. We estimated the respiratory phase after swallowing, frequency of SNIF, the duration of the respiratory pause during swallowing, and timing of swallowing in the respiratory cycle and compared these parameters among control, CPAP, and BiPAP conditions.
The expiration after swallowing (SW-E) frequency was associated with the occurrence of SNIF (
<0.01), pause duration ≤0.8 s (
<0.01), and timing of swallowing at the intermediate respiratory phase (50-80% of the respiratory cycle from the onset of inspiration) (
<0.01). In particular, the occurrence of SNIF most substantially affected the SW-E frequency. The SW-I frequencies under the control, CPAP, and BiPAP conditions were 35.0%, 3.0%, and 37.7%, respectively. The pause durations were shorter during CPAP and BiPAP than under the control condition (
<0.01). During CPAP, the occurrence rates of SW-E. Residual denotes the percentage difference between observed and expected values (residual =10.8:
<0.01) and SNIF (residual =9.1:
<0.01) were significantly increased, and timing of swallowing shifted toward the intermediate respiratory phase (residual=3.5:
<0.01).
CPAP decreases the SW-I frequency, increases the SNIF occurrence, and normalizes the timing of swallowing, all of which suggest that CPAP alleviates the risk of aspiration in patients with COPD.
Endoscopic evaluation of the excluded stomach after Roux-en-Y gastric bypass surgery for morbid obesity is a challenge, and the pathological changes that take place in the bypassed stomach are ...unclear. A new double-balloon method of evaluating the bypassed stomach after Roux-en-Y gastric bypass surgery for morbid obesity is described here.
This new enteroscope uses two balloons, one attached to the tip of the endoscope and the other to the distal end of the soft overtube. The procedures were carried out in six patients using the retrograde route, through the end-to-side jejunal anastomosis via the duodenobiliopancreatic limb up to the bypassed stomach.
The bypassed stomach was reached in five of six patients (83.3 %). An endoscopic appearance of atrophic gastritis was found in three patients, mild in two cases and severe in one case with intestinal metaplasia. Erosive and hemorrhagic gastritis was found in two patients.
Endoscopic evaluation of the bypassed stomach via the retrograde route after Roux-en-Y gastric bypass for morbid obesity is feasible using the double-balloon enteroscope.
The permeation of hydrogen through metals is of great concern in hydrogen containment systems. In this study, hydrogen contained in seamless coiled tube vessels made of SUS 316L and Inconel 625 ...permeated the vessel walls at temperatures from 573 K to 773 K, and the decreasing interior pressure of the vessels was monitored for an extended period to characterize the behavior of the pressure change. It was found that the pressure became lower than the surrounding atmospheric pressure, and the vessels reached a vacuum. Hydrogen permeabilities through SUS 316L and Inconel 625 were determined from the pressure drop measurements. In order to ensure the reliability of the measurements, the permeabilities were also determined with a gas chromatograph that measured the concentration of hydrogen completely permeating the vessel wall. The permeabilities obtained with the two methods were in good agreement with each other. The pressure drop behavior was compared to, and found to be consistent with, theoretical calculations performed using the obtained permeabilities based on Fick’s law of diffusion.
•Vacuum was generated by hydrogen permeation to atmosphere through vessel walls.•Pressure behavior in vessels was consistent with theoretical calculations.•Hydrogen permeabilities through SUS 316L and Inconel 625 were determined.
Summary
We investigated the impact of tongue‐thrusting on lingual pressure during fluid intake with a straw. In this study, 12 healthy young dentate individuals (two women and 10 men; 19–33 years) ...were instructed to drink 15 mL of water with a regular drinking straw at 37 °C, when indicated by the investigator. Participants drank after adjusting tongue position to one of the following patterns: (i) Holding the tip of the straw between the lips (Normal Position: NP), (ii) Sticking out the tongue to the vermilion zone of the lower lip and inserting the straw 1 cm past the front teeth (Tongue‐thrusting Position: TP). Five recordings were conducted for each participant in a randomised order. To measure tongue pressure during swallowing, a specially designed 0·1‐mm thick sensor sheet (Nitta, Osaka, Japan) with a tactile system for measurement of pressure distribution (I‐SCAN; Nitta) was used. Duration, maximal magnitude and integrated value of tongue pressure were analysed based on the wave of tongue pressure recorded while water was swallowed. Magnitude, duration and integrated value of tongue pressure were significantly lower in TP than in NP at the median line (Ch1–3). Magnitude and integrated value of tongue pressure at the lateral part of the tongue (Ch5) were significantly lower in TP than in NP. When duration, maximal magnitude and integrated values were compared by channel, no significant differences were observed in NP, but a significant difference was found between Ch3 and the lateral areas Ch4/Ch 5 in TP. When the tongue was thrust forward, movement dynamics of the entire tongue changed and influenced contact between the tongue and palate during liquid intake with a straw. The impact was noticeably weaker on the median line than in lateral areas.
Summary
Several dynamic magnetic resonance imaging (MRI) techniques to observe swallowing and their parameters have been reported. Although these studies used several contrast enhancement liquids, no ...studies were conducted to investigate the most suitable liquids. The purpose of this study was to identify the optimal contrast enhancement liquid for dynamic MRI of swallowing. MRI was performed using a new sequence consisting of true fast imaging with steady‐state precession, generalised auto‐calibrating partially parallel acquisition and a keyhole imaging technique. Seven liquids were studied, including pure distilled water, distilled water with thickener at 10, 20 and 30 mg mL−1 concentrations and oral MRI contrast medium at 1, 2 or 3 mg mL−1. Distilled water showed the highest signal intensity. There were statistically significant differences among the following contrast media: distilled water with thickener at 20 mg mL−1 and the oral MRI contrast medium at 2 mg mL−1 and 1 mg mL−1. It can be concluded that the optimal liquid for dynamic MRI of swallowing is a water‐based substance that allows variations in viscosity.
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