• Advances in pediatric surgery
• /
• v.14 no.1
• /
• pp.27-36
• /
• 2008

Fundoplication is a common surgical procedure for gastroesophageal reflux disease (GERD). Recently the procedure has been performed with increased frequency laparoscopically. The aim of this study is to review our 11 years experience with fundoplication in infants and children. From October 1994 to December 2005, 59 fundoplications in 55 patients were performed at Sungkyunkwan University Samsung Medical Center. Medical records and laboratory results of these children were retrospectively reviewed for sex, age, symptoms and signs, coexisting disease, diagnostic methods, treatment modalities and length of operative time. Open fundoplication was performed in 41 cases and laparoscopic fundoplication in 18 cases. Simultaneous gastrostomy was done in 27 cases. Recurrent GERD symptom occurred in four patients (7.2 %) within 2 years after first fundoplication and all 4 patients had re-do fundoplication. There were no intra- and immediate post-operative complications. Gastrointesitnal symptoms were the most common indication for fundoplication in neurologically normal patients. The most frequent diagnostic studies were upper gastrointestinal series (76.3 %) and 24 hour esophageal pH monitoring (78.2 %). Fundoplication had been increased since 2004 and mostly done laparoscopically. In conclusion, our 11 years' practice of open and laparoscopic fundoplication indicates that both approaches are safe and effective in the treatment of GERD for infants and children.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.45 no.9
• /
• pp.67-74
• /
• 2008

This paper proposes, designs and implements an architecture of a server involved with the network camera based video surveillance systems to solve common problems including lack of inter-network operability at the video information sharing, drawback of bandwidth and processing-overhead caused by increase of the number of users, and difficulty of continuous monitoring over changes of network configurations. The proposed saver was designed to manage and service numerous network cameras and users as well as solving the existing problems by providing video distribution facility. Through the empirical study after applying the implemented server to a real video surveillance system we proved that the server can provide reasonable service quality while it processes several hundreds of simultaneous user connections under persisting more than one hundred connections to network cameras. We expect the developed video distribution server to enhance service quality of the large scale video surveillance systems for citizen-wide services such as traffic reporting informatics or natural calamities supporting.

• The Korean Journal of Mycology
• /
• v.37 no.2
• /
• pp.161-166
• /
• 2009

The purpose of the present study is to develop a simple, fast and sensitive LC/MS method for simultaneous separation and the determination of an active component in the oriental medicinal mushroom Cordyceps militaris. Based on this work, the contents of cordycepin in Cordyceps militaris fruiting cultivated on various media were determined and compared. And also, the nutritional components such as minerals and vitamins were determined in order to provide useful information to consumer as a food material. The analysis methods of nutritional components were chosen on the basis of AOAC. The optimum separation for cordycepin was achieved using a solvent gradient consisting of the mixture of 0.1% formic acid in methanol (solvent B) in a background of 0.1% formic acid in water (solvent A) as a mobile phase and a 3.0${\times}$150 Waters XTera column. Selective ion monitoring (SIR) mode ([M+H]+ at m/z 252) was used for quantitative analysis of cordycepin. The cultivated Cordyceps militaris on various media contained 1~14 /g of cordycepin, 0.65~1.08% of thiamine, 0.86~7.17% of riboflavin, and 3.01~5.26% of niacin. The content of mineral components varied on categories, especially contained 500~3500% of potassium as a major mineral. Cordycepin, niacin and potassium were found much higher in the fruiting cultivated with soy power media (gold 10) than other media.

• Preventive Nutrition and Food Science
• /
• v.18 no.4
• /
• pp.263-268
• /
• 2013

In this study, the quick HPLC-MS/MS method for the simultaneous separation of 2-acetyl-4(5)-tetrahydroxybuthylimidazole (THI) and 4-(5)-methylimidazole (4-MI) in alkaline medium was used for caramel color and processed foods in Korea. After a simple sample pretreatment, 51 4-MI-labeled samples were positive for 4-MI and 2 also contained THI. The concentration of 4-MI was 260.5~24, $499.3{\mu}g/kg$ in caramel color, less than $LOD{\sim}1,712.5{\mu}g/kg$ in sauce, 1,242.3, $5,972.2{\mu}g/kg$ in balsamic vinegar, $2,118.3{\sim}5,802.4{\mu}g/kg$ in complex seasoning, $82.7{\sim}5,110.6{\mu}g/kg$ in curry, and $29.9{\sim}464.4{\mu}g/kg$ in soft drinks. The recovery rate of 4-MI was 97.1~111.0% in sauce and 81.9~110.0% in powder and that of THI was 83.6{\sim}106.4% in sauce and 61.2{\sim}99.4% in powder. Our results concluded a safe amount of 4-MI and THI compared to the limit of Korea additive code but the processed foods do not have a limit of caramel color and 4-MI in Korea. Therefore, research and monitoring of 4-MI and THI is needed for processed foods in Korea.

• Analytical Science and Technology
• /
• v.13 no.4
• /
• pp.484-493
• /
• 2000

The simultaneous analysis of alkylphenols, chlorophenols and bisphenol A in biota samples was performed by gas chromatography-mass spectrometry-selected ion monitoring mode. The phenols were extracted from sample with organic solvent and Forisil and Silica columns for clean-up procedure were compared. Recovery studies were performed at 1-ppm level of phenols added to each biota sample. Their recoveries ranged between 83 and 116% with coefficient of variations of 2.4-11.9%. To improve the detection limits of phenols, trimethylsilyl (TMS) derivatization was applied. The gas chromatographic properties of free phenols and TMS derivatized phenols were also investigated.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.19 no.1
• /
• pp.12-19
• /
• 2016

Purpose: This study was performed to evaluate the quality of sleep in snoring obese children without obstructive sleep apnea (OSA); and to study the possible relationship between sleep interruption and gastroesophageal reflux (GER) in snoring obese children. Methods: Study subjects included 13 snoring obese children who were referred to our sleep lab for possible sleep-disordered breathing. Patients underwent multichannel intraluminal impedance and esophageal pH monitoring with simultaneous polysomnography. Exclusion criteria included history of fundoplication, cystic fibrosis, and infants under the age of 2 years. Significant association between arousals and awakenings with previous reflux were defined by symptom-association probability using 2-minute intervals. Results: Sleep efficiency ranged from 67-97% (median 81%). A total of 111 reflux episodes (90% acidic) were detected during sleep, but there were more episodes per hour during awake periods after sleep onset than during sleep (median 2.3 vs. 0.6, p=0.04). There were 279 total awakenings during the sleep study; 56 (20.1%) of them in 9 patients (69.2%) were preceded by reflux episodes (55 acid, 1 non-acid). In 5 patients (38.5%), awakenings were significantly associated with reflux. Conclusion: The data suggest that acid GER causes sleep interruptions in obese children who have symptoms of snoring or restless sleep and without evidence of OSA.

• Korean Journal of Pharmacognosy
• /
• v.31 no.4
• /
• pp.455-458
• /
• 2000

Research on pesticide residues as endocrine disruptors in natural medicines was initiated by Korea Food & Drug Administration this year. We determined the presence and levels of certain pesticides in selected natural medicines. The natural medicines collected this year are Glycyrrhiza Root, Cinnamon Bark, Pueraria Root, Polygonatum Rhizome, Jujube, Schizandra Fruit, Lycium Fruit, Liriope Tuber, Eucommia Bark, Peony Root, Korean Angelica, Dioscorea Rhizome, Cnidium Rhizome, Cassia Seed, Platycodon Root, Comus Fruit, Mentha Herb, Epimedium Herb, Bupleurum Root, and Ginger, which have no data for pesticide residues and 192 samples of them were circulated in Korea, 28 samples were circulated in China. In order to analyze many pesticides in large number of samples we used simultaneous multi-residue analysis of pesticides by GC-ECD, which was followed by GC-MSD analysis to confirm the identity of the detected pesticide in each sample.

• Applied Chemistry for Engineering
• /
• v.23 no.6
• /
• pp.577-582
• /
• 2012

In this work, vibrational circular dichroism (VCD) technique was applied for the determination of %EE of chiral compounds. It may provide an easy way to determine the %EE with a proper accuracy within 2% error ranges as well as the absolute configuration of enantiomers. We demonstrated herein a flow cell VCD (FT-VCD) technique for time-dependent %EE measurements. The simultaneous monitoring of the mole fraction and %EE for two chiral species (epichlorohydrin and glycidol mixture) in the mixture was shown to be successful without any further separation steps. Thus, we demonstrate that FT-VCD is an appropriate analytical tool to monitor the kinetics of reactions involving chiral molecules. FT-VCD also provides a convenient nondestructive approach for the time dependent determination of the optical purity of individual components in a reaction mixture containing chiral molecules.

• Structural Monitoring and Maintenance
• /
• v.2 no.3
• /
• pp.283-300
• /
• 2015

Visual condition inspections remain paramount to assessing the current deterioration status of a bridge and assigning remediation or maintenance tasks so as to ensure the ongoing serviceability of the structure. However, in recent years, there has been an increasing backlog of maintenance activities. Existing research reveals that this is attributable to the labour-intensive, subjective and disruptive nature of the current bridge inspection method. Current processes ultimately require lane closures, traffic guidance schemes and inspection equipment. This not only increases the whole-of-life costs of the bridge, but also increases the risk to the travelling public as issues affecting the structural integrity may go unaddressed. As a tool for bridge condition inspections, Unmanned Aerial Vehicles (UAVs) or, drones, offer considerable potential, allowing a bridge to be visually assessed without the need for inspectors to walk across the deck or utilise under-bridge inspection units. With current inspection processes placing additional strain on the existing bridge maintenance resources, the technology has the potential to significantly reduce the overall inspection costs and disruption caused to the travelling public. In addition to this, the use of automated aerial image capture enables engineers to better understand a situation through the 3D spatial context offered by UAV systems. However, the use of UAV for bridge inspection involves a number of critical issues to be resolved, including stability and accuracy of control, and safety to people. SLAM (Simultaneous Localisation and Mapping) is a technique that could be used by a UAV to build a map of the bridge underneath, while simultaneously determining its location on the constructed map. While there are considerable economic and risk-related benefits created through introducing entirely new ways of inspecting bridges and visualising information, there also remain hindrances to the wider deployment of UAVs. This study is to provide a context for use of UAVs for conducting visual bridge inspections, in addition to addressing the obstacles that are required to be overcome in order for the technology to be integrated into current practice.

• Wind and Structures
• /
• v.11 no.1
• /
• pp.35-50
• /
• 2008

Wind and temperature have been shown to be the critical sources causing changes in the modal properties of large-scale bridges. While the individual effects of wind and temperature on modal variability have been widely studied, the investigation about the effects of multiple environmental factors on structural modal properties was scarcely reported. This paper addresses the modeling of the simultaneous effects of wind and temperature on the modal frequencies of an instrumented cable-stayed bridge. Making use of the long-term monitoring data from anemometers, temperature sensors and accelerometers, a neural network model is formulated to correlate the modal frequency of each vibration mode with wind speed and temperature simultaneously. Research efforts have been made on enhancing the prediction capability of the neural network model through optimal selection of the number of hidden nodes and an analysis of relative strength of effect (RSE) for input reconstruction. The generalization performance of the formulated model is verified with a set of new testing data that have not been used in formulating the model. It is shown that using the significant components of wind speeds and temperatures rather than the whole measurement components as input to neural network can enhance the prediction capability. For the fundamental mode of the bridge investigated, wind and temperature together apply an overall negative action on the modal frequency, and the change in wind condition contributes less to the modal variability than the change in temperature.