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In endoscopic cricopharyngeal myotomy, surgeons sometimes have concerns about performing an adequate incision with only a narrow intra-cavital view from one direction. In order to overcome these issues, fluoroscopic radiography was used during endoscopic cricopharyngeal myotomy.
Peri-operative fluoroscopic radiography was utilised to check the position of the diverticuloscope, and to confirm the extent of the incision during surgery. A balloon catheter was used to determine whether the cricopharyngeal muscle was sufficiently resected. Blood loss, peri-operative complications, and functional oral swallowing scale and penetration aspiration scale scores were evaluated.
In 12 out of 15 patients, intra-operative fluoroscopic radiography showed the diverticuloscope positioned in the post-cricoid area, and the cricopharyngeal muscle was raised and the surgery completed without adverse effect. Swallowing functions improved following surgery.
Intra-operative fluoroscopy might improve endoscopic cricopharyngeal myotomy by allowing surgeons to confirm the extent of resection, and by reducing peri-operative morbidity and complication rates.
We aimed to verify the effectiveness of real-time reverse transcription (rRT) polymerase chain reaction (PCR) for detecting cases of modified measles (M-Me) and for predicting super-spreader candidates through the experience of a measles outbreak dominated by M-Me in Yamagata, Japan, during March–April 2017. We applied rRT-PCR to specimens from 35 cases of M-Me, nine cases of typical measles (T-Me) and nine cases of prodromal stage of T-Me (P-Me). From rRT-PCR among the M-Me cases, peripheral blood mononuclear cells (PBMC) showed the highest positive rate (80.0%), followed by throat swab (48.6%), urine (33.3%) and serum (3.1%). The negative result of PBMC in M-Me cases was recovered by the result of a throat swab. In specimens of PBMC, throat swab and urine, M-Me group showed the significantly higher cycle of threshold (i.e., lower viral load) in the rRT-PCR than T-Me and P-Me groups, respectively. Furthermore, three super-spreaders in T-Me or P-Me showed an extremely low cycle of threshold in their throat swab specimens. rRT-PCR using PBMC and throat swab might be helpful for clinical management and measles control by certain detection of M-Me cases and by predicting super-spreading events resulting from measles cases with the high viral load.
Elastocaloric materials exhibit extraordinary cooling potential, but the repetition of cyclic mechanical loadings during long-term operation of cooling systems requires the refrigerant material to have long fatigue life. This article reviews the fundamental cause of fatigue from aspects of initiation and propagation of fatigue cracks in shape-memory alloys (SMAs) that are used as elastocaloric materials, and highlights recent advances in using compression to overcome fatigue by curtailing the generation of surfaces associated with crack propagation. Compression is identified as a key means to extend fatigue lifetime in engineering design of elastocaloric cooling drive mechanisms. We summarize the state-of-the-art performance of different SMAs as elastocaloric materials and discuss the influence of low cyclic strains and high resistance to transformation. We present integration of compression-based material assemblies into a cooling system prototype and optimization of the system efficiency using work recovery and related measures.
Field surveys of supraglacial ponds on debris-covered glaciers in the Nepal Himalaya clarify that ice-cliff calving occurs when the fetch exceeds ∼80 m. Thermal undercutting is important for calving processes in glacial lakes, and subaqueous ice melt rates during the melt and freeze seasons are therefore estimated under simple geomorphologic conditions. In particular, we focus on the differences between valley wind-driven water currents in various fetches during the melt season. Our results demonstrate that the subaqueous ice melt rate exceeds the ice-cliff melt rate when the fetch is >20 m and water temperature is 2–4°C. Calculations suggest the onset of calving due to thermal undercutting is controlled by water currents driven by winds at the surface of the lake, which develop with expanding water surface.
A two-dimensional, finite-element calculation was performed to simulate the development of a snowdrift. The underlying two-dimensional topography was taken as the lower boundary, and this changed as the drift developed. The two-dimensional wind field was calculated from the Navier–Stokes equations. The calculation was performed until a quasi-steady state was reached, and the pattern of erosion and deposition was estimated by computing the divergence of snowdrift transport. Considering a snowdrift as a new surface, the wind field was then recalculated. Simulated results were compared with outdoor observations of the wind field and snowdrifts. The results were in fairly good agreement with each other, but more detailed research is regarded as being necessary.
We have made a CO(J=2-1) observations using the Nobeyama 45m telescope aimed at examining the physical properties of the molecular gas in this object. The upper limit obtained is 1.8 mK (3σ) at a velocity resolution of 100 km s−1, which leads to an upper limit on the molecular gas mass of 5.3 × 1011M⊙, if we assume a line width of 250 km s−1 obtained in the CO(J = 5 - 4) line (rest-frame) and the Galactic CO-to-H2 conversion factor of 4.5 (M⊙ K km s−1 pc2). The line ratio between the 2–1 line and the 5–4 line as well as those from the 7–6 and the 4–3 lines (Omont et al. 1996, Nature, 382, 428) imply that the mean gas density is as high as 103–5 cm−3, which is comparable to that in nearby star burst galaxies (e.g., Solomon et al. 1992, ApJ, 387, L55).
The hypothetical object called “failed cluster” of galaxies is described by Tucker et al. (1995, ApJ, 444, 532) as a large cloud of X-ray emitting hot gas without any visible galaxies. They made extensive survey of this type of objects using Einstein IPC database and found only one candidate, 0806+20.
We have made a CO (J=2−1) observation using the Nobeyama 45m telescope aimed at examining physical properties of the molecular gas in the object. Upper limit obtained is 1.8 mK (3σ) at a velocity resolution of 100 km s−1, which leads to an upper limit on the molecular gas mass of 5.3 × 1011M⊙, if we assume a line width of 250 km s−1 obtained in J = 5–4 line and the Galactic CO-to-H2 conversion factor of 4.5 M⊙ K km s−1 pc2. The line ratio between 2–1 line and 5–4 line as well as those from 7–6 and 4–3 lines (Omont et al. 1996) imply that the mean gas density is as high as 103–5 cm−3, which is comparable to that in nearby star burst galaxies (e.g., Solomon et al. 1992).
Infrared Imaging Surveyor (IRIS, officially Astro-F) is a satellite which will be launched in the winter of 2003. The main purpose of the IRIS mission is an all sky survey in the mid- and far-IR with a flux limit much deeper than that of IRAS. In order to examine the performance of the survey and to find a suitable set of bandpasses for tracing galaxy evolution and picking up protogalaxy candidates as effective as possible using IRIS, we estimated the FIR galaxy counts based on a simple model with various sets of cosmological parameters and evolution types.
Recently reported infrared galaxy number counts and cosmic infrared background (CIRB) measures all suggest that galaxies have experienced a strong evolutionary phase. We statistically estimated the galaxy evolution history from these data. We treated the evolution of galaxy luminosity as a stepwise nonparametric form, in order to explore the most suitable evolutionary history which satisfies the constraint from the CIRB. We found that an order of magnitude increase of the far infrared luminosity at redshift z = 0.75 - 1.0 was necessary to reproduce the very high CIRB intensity at ~ 150 μm reported by Hauser et al. (1998). We note that too large an evolutionary factor at high z overpredicts the CIRB intensity around 1 mm. The evolutionary history also satisfies the constraints from galaxy number counts obtained by IRAS, ISO and SCUBA. The rapid evolution of the IR luminosity density required from the CIRB well reproduces the very steep slope of galaxy number counts obtained by ISO. Based on this result and the evolution of optical luminosity density, we quantitatively discuss the contribution of starburst galaxies. In addition, we present the performance of the Japanese IRIS galaxy survey.
We investigated MOVPE growth conditions for AlInN layers with high growth rates and obtained 0.5µm/h with smooth surfaces. We found that short gas mixing time, relatively high growth temperature, and very low In/Al supply ratio were key growth parameters in order to obtain the AlInN layers with high growth rate and smooth surface simultaneously. AlInN/GaN DBRs grown under such growth conditions showed smooth surfaces and a reflectivity of over 99%.
We have investigated an influence of positive polarization charges generated at an interface between GaN barrier/p-AlGaN EB (Electron Blocking) layer in a blue-LED. Simulation results suggested that such polarization charges caused an electron overflow from QWs. The simulation results also indicated that sufficient acceptor doping at the interface could neutralize the positive polarization charges and suppress the electron overflow. We then demonstrated the electron overflow caused by the positive polarization charges and its suppression with sufficient Mg doping at the interface by monitoring emissions from an additional second QW inserted between the p-EB layer and the p-GaN layer. Finally we conclude that the contribution of the electron overflow is not significant for the efficiency droop in blue-LEDs.
Gallium nitride (n-type) films of thickness 300nm were grown on c-plane sapphire substrates using plasma assisted molecular beam epitaxy (PA-MBE). High resolution X-ray diffraction and photoluminescence measurements were used to confirm the crystalline and optical qualities of the grown films. Metal-semiconductor Schottky diodes were fabricated using Pt as the Schottky metal and Al as the Ohmic metal contact. Metal-insulator-semiconductor Schottky diodes were also fabricated using HfO2 (10nm) as the insulator material. Diode parameters like barrier height and ideality factor were extracted from I-V measurements. Introduction of HfO2 as the insulator layer leads to better rectifying behavior (forward to reverse current ratio improves from 5.1 to 8.9) with a reduction in reverse leakage current (by 7.4 times), increase in barrier height (from 0.62eV to 0.74eV) and a reduction in ideality factor (from 6 to 4.1) of the Schottky diode.
This study examined whether the occurrence of late neck metastasis in early tongue squamous cell carcinoma can be predicted by evaluating HMGB1 (high mobility group box 1) expression in the primary lesion.
A case–control study was conducted. The cases comprised 10 patients with late neck metastasis. The controls consisted of 16 patients without recurrence. All were examined immunohistochemically for HMGB1 protein expression. The odds ratio for late neck metastasis in relation to HMGB1 was estimated.
Results for HMGB1 were dichotomised into positive staining scores (score, 5–7) and negative scores (0–4). Six cases (60 per cent) and four controls (25 per cent) were HMGB1-positive. Although no significant result was seen, compared with HMGB1-negative patients the odds ratio for late neck metastasis in HMGB1-positive patients was 3.8 (95 per cent confidence interval, 0.6–26.5) after adjusting for other factors.
In the present study, immunohistochemical study of HMGB1 in early tongue squamous cell carcinoma did not appear to be very useful for predicting occult neck metastasis. Further study is necessary to clarify the relationship between HMGB1 expression and late neck metastasis in early tongue squamous cell carcinoma.
Multiwavelength Spectral Energy Distributions (SEDs) of far-infrared (FIR) galaxies detected in the AKARI South Ecliptic Poles Survey (ADF-S) allow to trace differences between [Ultra]-Luminous Infrared Galaxies ([U]LIRGS) and other types of star-forming galaxies (SF).