• KSBB Journal
• /
• v.14 no.3
• /
• pp.284-290
• /
• 1999

Glucose fed-batch culture was studied to improve cellulose productivity by Acetobacter xylinum BRC5. When initial glucose concentrations in batch cultures were less than 20 g/L, yield coefficients of cellulose (Yp/s) remained a constant value of 0.21 g cellulose/g glucose. But a low yield coefficient, Yp/s=0.13 was obtained from an initial glucose concentration of 40 g/L. Since initial high glucose concentrations in batch culture resulted in low yields of cellulose, constant fed-batch cultures were carried out. The optimal feed rate for fed-batch culture was 2.22 g glucose/L.h. In constant fed-batch culture without DO control, 10 g/L of cellulose was obtained from 40 g/L of glucose with this feed rate, which was approximately two fold higher than that of the batch culture with the same initial glucose concentration. In DO stat plus fed-batch culture, the highest cellulose productivity could be obtained when dissolved oxygen level was controlled at 10% of air saturation, and cellulose productivity increased about 1.5 times compared with that of the culture without DO control.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.10
• /
• pp.127-136
• /
• 2020

Purpose: This study aimed to establish a basis for application time and cold therapy interval by checking the physiological changes after applying a cold-gel and ice pack, commonly applied to cold therapy, and after passive rewarming. Method: A total of 22 healthy adults used cold-gel packs and ice packs in a Randomized control group repeated measurement study, and passive rewarming was performed for 40 minutes after 30 minutes of cold therapy. After applying to the right axilla, StO₂, SpO₂, peripheral blood flow, skin and body temperature were measured 15 times every 5 minutes. Result: In the cold-gel pack group, StO₂ decreased from 69.43% to 61.06% after 30 minutes application, and in the ice pack group, StO₂ decreased from 67.66% to 64.80% (p <001). In the cold-gel pack group, skin temperature decreased from 33.57℃ to 29.15℃ after 30 minutes application, and in the ice pack group, skin temperature decreased from 32.64℃ to 28.90℃ (p <.001). Only skin temperature recovered completely after 40 minutes of rewarming. There were insignificant differences between the cold-gel pack and ice pack. Conclusion: When applying cold therapy to the axillary, at least 40 minutes for passive rewarming is necessary after 30 minutes of application.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.43 no.4
• /
• pp.229-238
• /
• 2017

Objectives: The primary purpose of this study was to investigate the factors related with additional administration of sedative agent during intravenous conscious sedation (IVS) using midazolam (MDZ). The secondary purpose was to analyze the factors affecting patient satisfaction. Materials and Methods: Clinical data for 124 patients who had undergone surgical extraction of mandibular third molar under IVS using MDZ were retrospectively investigated in this case-control study. The initial dose of MDZ was determined by body mass index (BMI) and weight. In the case of insufficient sedation at the beginning of surgery, additional doses were injected. During surgery, peripheral oxygen saturation, bispectral index score (BIS), heart rate, and blood pressure were monitored and recorded. The predictor variables were sex, age, BMI, sleeping time ratio, dental anxiety, Pederson scale, and initial dose of MDZ. The outcome variables were additional administration of MDZ, observer's assessment of alertness/sedation, intraoperative amnesia, and patient satisfaction. Descriptive statistics were computed, and the P-value was set at 0.05. Results: Most patients had an adequate level of sedation with only the initial dose of MDZ and were satisfied with the treatment under sedation; however, 19 patients needed additional administration, and 13 patients were unsatisfied. In multivariable logistic analysis, lower age (odds ratio [OR], 0.825; P=0.005) and higher dental anxiety (OR, 5.744; P=0.003) were related to additional administration; lower intraoperative amnesia (OR, 0.228; P=0.002) and higher BIS right before MDZ administration (OR, 1.379; P=0.029) had relevance to patient dissatisfaction. Conclusion: The preoperative consideration of age and dental anxiety is necessary for appropriate dose determination of MDZ in the minor oral surgery under IVS. The amnesia about the procedure affects patient satisfaction positively.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2014.02a
• /
• pp.344-344
• /
• 2014

Transparent amorphous oxide semiconductors such as a In-Ga-Zn-O (a-IGZO) have advantages for large area electronic devices; e.g., uniform deposition at a large area, optical transparency, a smooth surface, and large electron mobility >10 cm2/Vs, which is more than an order of magnitude larger than that of hydrogen amorphous silicon (a-Si;H).1) Thin film transistors (TFTs) that employ amorphous oxide semiconductors such as ZnO, In-Ga-Zn-O, or Hf-In-Zn-O (HIZO) are currently subject of intensive study owing to their high potential for application in flat panel displays. The device fabrication process involves a series of thin film deposition and photolithographic patterning steps. In order to minimize contamination, the substrates usually undergo a cleaning procedure using deionized water, before and after the growth of thin films by sputtering methods. The devices structure were fabricated top-contact gate TFTs using the a-IGZO films on the plastic substrates. The channel width and length were 80 and 20 um, respectively. The source and drain electrode regions were defined by photolithography and wet etching process. The electrodes consisting of Ti(15 nm)/Al(120 nm)/Ti(15nm) trilayers were deposited by direct current sputtering. The 30 nm thickness active IGZO layer deposited by rf magnetron sputtering at room temperature. The deposition condition is as follows: a rf power 200 W, a pressure of 5 mtorr, 10% of oxygen [O2/(O2+Ar)=0.1], and room temperature. A 9-nm-thick Al2O3 layer was formed as a first, third gate insulator by ALD deposition. A 290-nm-thick SS6908 organic dielectrics formed as second gate insulator by spin-coating. The schematic structure of the IGZO TFT is top gate contact geometry device structure for typical TFTs fabricated in this study. Drain current (IDS) versus drain-source voltage (VDS) output characteristics curve of a IGZO TFTs fabricated using the 3-layer gate insulator on a plastic substrate and log(IDS)-gate voltage (VG) characteristics for typical IGZO TFTs. The TFTs device has a channel width (W) of $80{\mu}m$ and a channel length (L) of $20{\mu}m$. The IDS-VDS curves showed well-defined transistor characteristics with saturation effects at VG>-10 V and VDS>-20 V for the inkjet printing IGZO device. The carrier charge mobility was determined to be 15.18 cm^2 V-1s-1 with FET threshold voltage of -3 V and on/off current ratio 10^9.

• Clinical and Experimental Pediatrics
• /
• v.61 no.6
• /
• pp.187-193
• /
• 2018

Purpose: The efficacy of percutaneous stent implantation for congenital heart disease (CHD) in Korea, where stent availability is limited, has not been determined. This study evaluated the acute and midterm results of stent implantation in different CHD subgroups. Methods: Stents were implanted in 75 patients with 81 lesions: (1) pulmonary artery stenosis (PAS) group, 56 lesions in 51 patients; (2) coarctation of the aorta (CoA) group, 5 lesions in 5 patients; (3) Fontan group, 13 lesions in 12 patients; (4) ductal stent group, 3 lesions in 3 patients; and (5) other CHD group, 4 lesions in 4 patients. Mean follow-up duration was 2.1 years (0.1-4 years). Medical records were reviewed retrospectively. Results: The minimum lumen diameter (MLD) in PAS and CoA increased from $5.0{\pm}1.9mm$ and $8.4{\pm}1.6mm$ to $10.1{\pm}3.6mm$ and $12.3{\pm}2.5mm$, respectively (P<0.01). In the PAS group, pressure gradient decreased from $25.7{\pm}15.6mmHg$ to $10.4{\pm}10.1mmHg$, and right ventricular to aortic pressure ratio from $0.56{\pm}0.21$ to $0.46{\pm}0.19$. In the CoA group, the pressure gradient decreased from $50{\pm}33mmHg$ to $17{\pm}8mmHg$. In the ductal stent group, the MLD of the ductus increased from 2.3 mm to 4.3 mm and arterial oxygen saturation from 40%-70% to 90%. No deaths were associated with stent implantation. Stent migration occurred in 3 patients, but repositioning was successful in all. Stent redilation was performed successfully in 26 cases after $29{\pm}12months$. Conclusion: Percutaneous stent implantation was safe and effective, with acceptable short and mid-term outcomes in Korean CHD patients.

• The Journal of Internal Korean Medicine
• /
• v.38 no.5
• /
• pp.789-796
• /
• 2017

Objectives: We examined the effects of Sinbi-tang on a patient with pontine hemorrhage and respiratory disturbance. Methods: A patient diagnosed with pontine hemorrhage and respiratory disturbance was treated with herbal medicine and acupuncture. We checked the peripheral oxygen saturation ($SpO^2$) by oximetry three times a day, and obtained an average value. We evaluated the improvement of symptoms by changes in the average applied $O^2$ and average $SpO^2$. Results: After taking Sinbi-tang and treatment with acupuncture therapy, the patient showed improvement in respiratory disturbance. Applied $O^2$ was gradually decreased from 4 L/min to 0 L/min and $SpO^2$ was stabilized. Conclusions: Korean medicine may provide effective treatment for respiratory disturbance in patients with pontine hemorrhage, but further study is needed.

• Journal of Internet Computing and Services
• /
• v.17 no.2
• /
• pp.59-65
• /
• 2016

The result of analyzing the cognitive reaction due to the color environment has been applied to various filed especially in medical field. Moreover, the study about the identification of patient's condition and examination the brain activity by collecting the bio-signal based on the color environment is being actively conducted. Even though, there were a variety of experiments by convention the color environment using a light or LED color, it still has a problem that affects the psychological information. Therefore, our proposed system using a HMD (Head Mounting display) to provide a completed color environment condition. This system uses the BMS(Biomedical System) to collect the biometric information which responds to the specific color condition and the human body response information can be measured by the development the Memory and Attention test on Mobile phone. The collection of Biometric information includes electro cardiogram(ECG), respiration, oxygen saturation (Sp02), Bio-impedance, blood pressure will store in the database. In addition, we can verify the result of the human body reaction in the color environment by Memory and Attention application. By utilizing the reaction of the human body information that is collected thought the proposed system, we can analyze the correlation between the physiological information and the color environment. And we also expect that this system can apply to the medical diagnosis and treatment. For future work, we will expand the system for prediction and treatment of Alzheimer disease by analyzing the visualization data through the proposed system. We will also do evaluation on the effectiveness of the system for using in the rehabilitation program.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.02a
• /
• pp.265-265
• /
• 2012

The adsorption of molecular $NH_3$ on rutile $TiO_2(110)-1{\times}1$ surfaces was investigated using a temperature-programmed desorption (TPD) technique combined with a molecular beam apparatus. A quantitative investigation into the TPD spectra of $NH_3$ was made for $NH_3$ adsorbed on two kinds of rutile $TiO_2(110)-1{\times}1$ surfaces with the oxygen vacancy ($V_O$) concentration of ~0% (p-$TiO_2(110)$) and ~5% (r-$TiO_2(110)$), respectively. On both surfaces, non-dissociative adsorption of $NH_3$ was inferred from a quantitative analysis on the amount of adsorbed $NH_3$ and those desorbed. With increasing coverage, the monolayer desorption feature shifted from 400 K toward lower temperatures until it saturates at 160 K, suggesting a repulsive nature in the interaction between $NH_3$ molecules. At the very low coverage regime, the desorption features were found to extend up to 430 K and 400 K on p-$TiO_2(110)$ and p-TiO(110), respectively. As a result, the saturation coverage of monolayer of $NH_3$ was higher on the p-$TiO_2(110)$ surface than on the p-TiO(110) by about 10%. The desorption energy ($E_d$) of $NH_3$ obtained by inversion of the Polanyi-Wigner equation indicated that the difference between the $E_d$'s of $NH_3$ (that is, $E_d(on\;p-TiO_2(110)$) - $E_d$(on p-TiO(110)) was 14 kJ/mol at ${\theta}(NH_3)=0$ and decreased to 0 as the coverage approached to a monolayer. The observed adsorption behavior of $NH_3$ was interpreted using an interaction model between $NH_3$ and surface defects on $TiO_2$ such as VO's and $Ti^{3+}$ interstitials.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.32 no.2
• /
• pp.262-269
• /
• 2005

The purpose of this study was to compare the efficacy and complications of two oral sedative regimens, chloral hydrate (60mg/kg)/hydroxyzine(25mg) versus midazolam(1mg/kg)/meperidine(1mg/kg) for the sedation of pediatric dental patients. Fifteen patients(mean age 36.2months, range 24-47months), ASA Class I or II, who needed at least two restorative dental procedures were selected in this double-blind, randomized study. All subjects were randomly assigned to receive either chloral hydrate/hydroxyzine or midazolam/meperidine and 50% $N_2O/O_2$ was administered at each appointment. Behavior assessment(sleep, movement, crying, overall behavior) was made using Houpt Sedation Rating Scale and physiologic parameters(pulse rate, oxygen saturation) were monitored using pulse oximeter. The incidence of hypoxia($SpO_2$ 90% or less, at least 10s duration) and vomiting was recorded. Patients sedated with chloral hydrate/hydroxyzine showed significantly better overall behavior score than patients sedated with midazolam/meperidine. There was no clinically significant difference in the incidence of hypoxia and vomiting. It was concluded that oral administration of chloral hydrate/hydroxyzine is more effective than midazolam/meperidine for the sedation of pediatric dental patients.

• Journal of Aquaculture
• /
• v.16 no.1
• /
• pp.15-23
• /
• 2003

We have investigated water quality of the coastal saline groundwaters utilized for fish farms in Jeju Island. The water quality investigation included the spatial observations for 75 fish farms during March-May, 1994 and the hi-monthly observations for both coastal saline groundwaters and seawaters at four fish farms from August 1994 to December 1995. Water temperature of the saline groundwaters ranged from 16 to 18$^{\circ}C$ over the study period. Salinity of the saline groundwaters varied between 20.60 ppt and 34.02 ppt, slightly lower than that of the coastal seawaters(26.47~34.53 ppt). This salinity variation must be associated with local precipitation conditions in Jeju Island. The oxygen saturation for most saline groundwater samples was lower than 80%, ranging from 24.7 to 89.8%. The COD and pH values for the saline groundwaters were similar to those for the coastal seawaters. The concentrations of DIP for the saline groundwaters varied between 0.021 mg/L and 0.121 mg/ L, and seasonal variation of DIP in the saline groundwater ranged from 0.014 to 0.077 mg/L, which were higher than that of the coastal seawaters(0.000~0.015 mg/L). Nitrate in the saline groundwaters accounted for more than 90% of the DIM. The maximum concentrations of ammonia, nitrite, nitrate and DIN in the saline groundwaters were 0.085, 0.012, 2.294 and 2.309 mg/L, respectively. These concentrations of the saline groundwaters were considerably lower than those affected culture organisms. Overall, the saline groundwaters utilized for fish farms in Jeju Island appear to maintain good waterquality for fish farms.