• Title/Summary/Keyword: pulse-tube

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Clinical Factors Associated with the Non-Operative Airway Management of Patients with Robin Sequence

  • Albino, Frank P.;Wood, Benjamin C.;Han, Kevin D.;Yi, Sojung;Seruya, Mitchel;Rogers, Gary F.;Oh, Albert K.
    • Archives of Plastic Surgery
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    • v.43 no.6
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    • pp.506-511
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    • 2016
  • Background The indications for surgical airway management in patients with Robin sequence (RS) and severe airway obstruction have not been well defined. While certain patients with RS clearly require surgical airway intervention and other patients just as clearly can be managed with conservative measures alone, a significant proportion of patients with RS present with a more confusing and ambiguous clinical course. The purpose of this study was to describe the clinical features and objective findings of patients with RS whose airways were successfully managed without surgical intervention. Methods The authors retrospectively reviewed the medical charts of infants with RS evaluated for potential surgical airway management between 1994 and 2014. Patients who were successfully managed without surgical intervention were included. Patient demographics, nutritional and respiratory status, laboratory values, and polysomnography (PSG) findings were recorded. Results Thirty-two infants met the inclusion criteria. The average hospital stay was 16.8 days (range, 5-70 days). Oxygen desaturation (<70% by pulse oximetry) occurred in the majority of patients and was managed with temporary oxygen supplementation by nasal cannula (59%) or endotracheal intubation (31%). Seventy-five percent of patients required a temporary nasogastric tube for nutritional support, and a gastrostomy tube placed was placed in 9%. All patients continued to gain weight following the implementation of these conservative measures. PSG data (n=26) demonstrated mild to moderate obstruction, a mean apneahypopnea index (AHI) of $19.2{\pm}5.3events/hour$, and an oxygen saturation level <90% during only 4% of the total sleep time. Conclusions Nonsurgical airway management was successful in patients who demonstrated consistent weight gain and mild to moderate obstruction on PSG, with a mean AHI of <20 events/hour.

The Development of Electric Ballast for a Instant Start/Restart of Metalhalide Lamp (메탈핼라이드램프용 순시점등/재점등 전자식안정기 개발)

  • Kim, Su-Kyoung;Jang, Woo-Jin
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.18 no.5
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    • pp.9-15
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    • 2004
  • The most shortcoming of metalhalide lamps is what the instant restarting cannot be realized when the arc tube is in the hot condition. The discharge starting voltage of arc tube in the hot condition is much higher than in the cold condition. Therefore it takes about five minutes to restart the metalhalide lamps, that is to say, it is possible to start when the pressure and the temperature are decreased. But, if the lamp is restarted in the hot condition, we must supply the high voltage pulse with 20[kV] at the both electrode of lamp. The proposed electronic ballast is consist of a electromagnetic interference(EMI) filter, a power factor correction(PFC) circuit, a flyback converter, a half-bridge inverter, and a high voltage igniter circuit. By this composition we can start/restart the lamp with the voltage 20[kV], even if the lamp is in the hot condition.

A Study of X-ray Output for Diagnostic X-ray Equipment (진단용 X선 발생 장치의 X선 출력에 관한 연구)

  • Ko, Shin-Gwan;Ahn, Bong-Seon;Jang, Sang-Sup;Choi, Jong-Woon;Shin, Young-Soon
    • Journal of radiological science and technology
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    • v.18 no.2
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    • pp.61-73
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    • 1995
  • For the managements of the diagnostic X-ray equipments, the authors examined the output of single phase rectification assembly, Three phase rectification assembly and serial radiographic appartus, and got the following conclusions. 1. When the tube voltages in X-ray control panels ware compared to the measured values on the kVp pulse meter, only little differences were detected in all the X-ray equipments. And most of the equipments were all well managed within the internationally permitted limits, excepting the 12.02 % error at 120 kVp in three phase rectifying assembly. 2. As for the X-ray qualities affecting the X-ray images, the serial radiographic apparatus showed excellence, while the single phase rectification assembly were somewhat inferior to the others only maining the internationally recommended limits. 3. The tube voltage ranges where the X-ray output showed excellence were $100{\sim}200\;mA$ in serial radiographic apparatus, $200{\sim}350\;mA$ in three phase rectification assembly and $350{\sim}400\;mA$ in single phase rectification assembly respectively. 4. In the repeatability test of the X-ray equipments, CVs were in the range of $0.0029{\sim}0.049$, which is within the HEW or KS standards. Consequently all the equipments are thought to be well-manage. 5. This study on characteristics and output of the X-ray equipments was accomplished within a limited short time. Long-time researches on the function managements for the X-ray equipments should be followed along with the periodical checking the output for reduction of X-ray exposures to the patients or radio-technologists, and for maintanance and prediction of trouble of the equipments.

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The three-dimensional temporal behavior measurement of light emitted from plasma display panel by the Scanned Point-Detecting System (Scanned Point-Detecting System을 이용한 플라즈마 디스플레이 패널에서 방출되는 광의 3차원 시간 분해 측정)

  • 최훈영;이석현;이승걸;김준엽
    • Korean Journal of Optics and Photonics
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    • v.13 no.6
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    • pp.559-563
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    • 2002
  • We measure the 3-dimensional temporal behavior of the light emitted from the discharge cell of a plasma display panel (PDP) by using a scanned point detecting system. The light signal detected by a PM tube is sent to the oscilloscope, and the oscilloscope is connected to a PC with GPIB. From the resultant temporal behaviors, we could analyze the discharge characteristics of the panel with a Ne-Xe (4%) mixing gas at a 400 torr pressure. The top view of the panel shows that discharge moves from the inner edge of the cathode electrode to the outer cathode electrode, forming an arc shape. The side view of the panel shows that the light is detected up to 150 $\mu\textrm{m}$ up the barrier rib. After a trigger pulse is applied, peak intensity is detected at 730 ns and peak intensity position is located at the center of the ITO electrodes.

Fabrication and Characteristics of X-ray Position Detection Sensor (방사선 위치 검출센서의 제작 및 특성)

  • Park, Hyung-Jun;Kim, In-Su
    • Journal of IKEEE
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    • v.19 no.4
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    • pp.535-540
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    • 2015
  • A microstrip gas chamber (MSGC), applied to digital radiography system, was designed and constructed. The microstrip electrodes were fabricated with Chrome(Cr.). by photolithography process on Silicon(Si) wafer and glass substrate. The width of anode and cathode electrodes was $10{\mu}m$, and $290{\mu}m$, respectively. The distance of the electrodes was $100{\mu}m$, and the active area was $50{\times}50mm^2$. And the number of anode was 80. The microstrip electrodes were damaged when discharges occurred over the 600 V of anode voltage. As the result of experiments. It detected the typical output signals of the pulse width, 20 ns, under the condition that the detecting gas was Ar(90%) + $CH_4$(10%), X-ray tube voltage was 42 kV, and tube current was 1 mA.

Development of the Automated Ultrasonic Flaw Detection System for HWR Nuclear Fuel Cladding Tubes (중수로형 핵연료 피복관의 자동초음파탐상장치 개발)

  • Choi, M.S.;Yang, M.S.;Suh, K.S.
    • Nuclear Engineering and Technology
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    • v.20 no.3
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    • pp.170-178
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    • 1988
  • An automated ultrasonic flaw detection system was developed for thin-walled and short tubes such as Zircaloy-4 tubes used for cladding heavy-water reactor fuel. The system was based on the two channels immersion pulse-echo technique using 14 MHz shear wave and the specially developed helical scanning technique, in which the tube to be tested is only rotated and the small water tank with spherical focus ultrasonic transducers is translated along the tube length. The optimum angle of incidence of ultrasonic beam was 26 degrees, at which the inside and outside surface defects with the same size and direction could be detected with the same sensitivity. The maximum permissible defects in the Zircaloy-4 tubes, i.e., the longitudinal and circumferential v notches with the length of 0.76mm and 0.38mm, respectively and the depth of 0.04 mm on the inside and outside surface, could be easily detected by the system with the inspection speed of about 1 m/min and the very excellent reproducibility. The ratio of signal to noise was greater than 20 dB for the longitudinal defects and 12 dB for the circumferential defects.

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Fertigation Techniques Using Fertilizers with Peristaltic Hose Pump for Hydroponics (연동펌프를 이용한 비료염 공급 관비재배기술 연구)

  • Kim, D.E.;Lee, G.I.;Kim, H.H.;Woo, Y.H.;Lee, W.Y.;Kang, I.C.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.17 no.1
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    • pp.57-71
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    • 2015
  • This study was conducted to develop the fertigation system with a peristaltic hose pump and brushless DC motor. The fertigation system was consisted of sensor, main controller, motor control unit, peristaltic pump, water supply pump, control panel, and filter. The peristaltic pump discharges liquid by squeezing the tube with rollers. Rollers attached to the external circumference of the rotor compresses the flexible tube. The fluid is contained within a flexible tube fitted inside a circular pump casing. The developed fertigation system has no mixing tank but instead injects directly a concentrated nutrient solution into a water supply pipe. The revolution speed of the peristaltic pump is controlled by PWM (Pulse width modulation) method. When the revolution speed of the peristaltic pump was 300rpm, the flow rate of the 3.2, 4.8, 6.3mm diameter tube was 202, 530, 857mL/min, respectively. As increasing revolution speed, the flow rate of the peristaltic pump linearly increased. As the inner diameter of a tube larger, a slope of graph is more steep. Flow rate of three roller was more than that of four roller. Flow rate of a norprene tube with good restoring force was more than that of a pharmed tube. As EC sensor probe was installed in direct piping in comparison with bypass piping showed good performance. After starting the system, it took 16~17 seconds to stabilize EC. The maximum value of EC was 1.44~1.7dS/m at a setting value of 1.4dS/m. The developed fertigation system showed ±0.06dS/m deviation from the setting value of EC. In field test, Cucumber plants generally showed good growth. From these findings, this fertigation system can be appropriately suitable for fertigation culture for crops.

In Vitro imaging of MRI and Ultrasound for Colorectal Carcinoma (직결장암 조직의 자기공명영상과 초음파 소견에 대한 비교 연구)

  • Lee, Hwang Kyu;Jee, Keum Nahn;Hong, Sujin;Koh, Jae Hyang
    • Investigative Magnetic Resonance Imaging
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    • v.17 no.2
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    • pp.133-143
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    • 2013
  • Purpose : To evaluate and compare the accuracy of magnetic resonance imaging (MRI) and ultrasound (US) for detection and estimation of invasion depth of colorectal carcinoma (CRC) by correlation with histopathologic findings in vitro, and to find out the best MR pulse sequence for accurate delineation of tumor from surrounding normal tissue. Materials and Methods: Resected specimens of CRC from 45 patients were examined about tumor detectability and invasion depth of US using high frequency (5-17 MHz) linear transducer in a tube filled with normal saline and MRI in a 8-channel quadrate head coil. The institutional review board approved this study and informed consent was waived. MRI with seven pulse sequences of in- and out-of-phases gradient echo T1 weighted images, fast spin echo T2 weighted image and its fat suppression image, fast imaging employing steady-state acquisition (FIESTA) and its fat suppression image, and diffusion weighted image (DWI) were performed. In each case, both imaging findings of MRI and US were evaluated independently for detection and estimation of invasion depth of tumor by consensus of two radiologists and were compared about diagnostic accuracy according to the histopathologic findings as reference standard. Seven MR pulse sequences were evaluated on the point of accurate delineation of tumor from surrounding normal tissue in each specimen. Results: In specimens of CRC, both imaging modalities of MRI (91.1%) and US (86.7%) showed relatively high diagnostic accuracy to detect tumor and evaluate invasion depth of tumor. In early CRC, diagnostic accuracy of US was 87.5% and that of MRI was 75.0%. There was no statistically significant difference between two imaging modalities (p > 0.05). The best pulse sequence among seven MR sequences for accurate delineation of tumor from surrounding normal tissue in each specimen of CRC was fast spin echo T2 weighted image. Conclusion: MRI and US show relatively high diagnostic accuracy to detect tumor and evaluate invasion depth of resected specimen of CRC. The most excellent pulse sequence of MRI for accurate delineation of tumor from surrounding normal tissue in CRC is fast spin echo T2 weighted image.

Flow Effects on Tailored RF Gradient Echo (TRFGE) Magnetic Resonance Imaging : In-flow and In-Plane Flow Effect (Tailored RF 경자사계방향 (TRFGE} 자기공명영상(MRI)에서 유체에 의한 영상신호 변화 : 유체유입효과와 영상면내를 흐르는 유체의 효과에 대하여)

  • Mun, Chi-Ung;Kim, Sang-Tae;No, Yong-Man;Im, Tae-Hwan;Jo, Jang-Hui
    • Journal of Biomedical Engineering Research
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    • v.18 no.3
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    • pp.243-251
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    • 1997
  • In this paper, we have reported two interesting flow effects arising in the TRFGE sequence using water flow phantom. First, we have shown that the TRFGE sequence is indeed not affected by "in-flow" effect from the unsaturated spins flowing into the imaging slice. Second, the enhancement of "in-plane flow" signal in the readout gradient direction was observed when the TRFGE sequence was used without flow compensation. These two results have many interesting applications in MR imaging other than fMRI. Results obtained were also compared with the results obtained by the conventional gradient echo(CGE) imaging. Experiments were performed at 4.7T MRI/S animal system (Biospec, BRUKER, Switzerland). A cylindrical phantom was made using acryl and a vinyl tube was inserted at the center(Fig. 1). The whole cylinder was filled with water doped with $MnCl_2$ and the center tube was filled with saline which flows in parallel to the main magnetic field along the tube. Tailored RF pulse was designed to have quadratic ($z^2$) phase distribution in slice direction(z). Imaging parameters were TR/TE = 55~85/10msec, flip angle = $30^{\circ}$, slice thickness = 2mm, matrix size = 256${\times}$256, and FOV= 10cm. In-flow effect : Axial images were obtained with and without flow using the CGE and TRFGE sequences, respectively. The flow direction was perpendicular to the image slice. In-plane flow : Sagittal images were obtained with and without flow using the TRGE sequence. The readout gradient was applied in parallel to the flow direction. We have observed that the "in-flow" effect did not affect the TRFGE image, while "in-plane flow" running along the readout gradient direction enhanced the signal in the TRFGE sequence when flow compensation gradient scheme was not used.

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Effects of exploration and molecular mechanism of CsV on eNOS and vascular endothelial functions

  • Zuo, Deyu;Jiang, Heng;Yi, Shixiong;Fu, Yang;Xie, Lei;Peng, Qifeng;Liu, Pei;Zhou, Jie;Li, Xunjia
    • Advances in nano research
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    • v.12 no.5
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    • pp.501-514
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    • 2022
  • This study aimed to investigate the effects and potential mechanisms of Chikusetsusaponin V (CsV) on endothelial nitric oxide synthase (eNOS) and vascular endothelial cell functions. Different concentrations of CsV were added to animal models, bovine aorta endothelial cells (BAECs) and human umbilical vein endothelial cells (HUVECs) cultured in vitro. qPCR, Western blotting (WB), and B ultrasound were performed to explore the effects of CsV on mouse endothelial cell functions, vascular stiffness and cellular eNOS mRNA, protein expression and NO release. Bioinformatics analysis, network pharmacology, molecular docking and protein mass spectrometry analysis were conducted to jointly predict the upstream transcription factors of eNOS. Furthermore, pulldown and ChIP and dual luciferase assays were employed for subsequent verification. At the presence or absence of CsV stimulation, either overexpression or knockdown of purine rich element binding protein A (PURA) was conducted, and PCR assay was employed to detect PURA and eNOS mRNA expressions, Western blot was used to detect PURA and eNOS protein expressions, cell NO release and serum NO levels. Tube formation experiment was conducted to detect the tube forming capability of HUVECs cells. The animal vasodilation function test detected the vasodilation functions. Ultrasonic detection was performed to determine the mouse aortic arch pulse wave velocity to identify aortic stiffness. CsV stimulus on bovine aortic cells revealed that CsV could upregulate eNOS protein levels in vascular endothelial cells in a concentration and time dependent manner. The expression levels of eNOS mRNA and phosphorylation sites Ser1177, Ser633 and Thr495 increased significantly after CsV stimulation. Meanwhile, CsV could also enhance the tube forming capability of HUVECs cells. Following the mice were gavaged using CsV, the eNOS protein level of mouse aortic endothelial cells was upregulated in a concentration- and time-dependent manner, and serum NO release and vasodilation ability were simultaneously elevated whereas arterial stiffness was alleviated. The pulldown, ChIP and dual luciferase assays demonstrated that PURA could bind to the eNOS promoter and facilitate the transcription of eNOS. Under the conditions of presence or absence of CsV stimulation, overexpression or knockdown of PURA indicated that the effect of CsV on vascular endothelial function and eNOS was weakened following PURA gene silence, whereas overexpression of PURA gene could enhance the effect of CsV upregulating eNOS expression. CsV could promote NO release from endothelial cells by upregulating the expression of PURA/eNOS pathway, improve endothelial cell functions, enhance vasodilation capability, and alleviate vessel stiffness. The present study plays a role in offering a theoretical basis for the development and application of CsV in vascular function improvement, and it also provides a more comprehensive understanding of the pharmacodynamics of CsV.