• Journal of Chest Surgery
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• 제26권11호
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• pp.866-870
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• 1993

Possible enhancement of myocardial protection with oxygenated crystalloid cardioplegia and blood cardioplegia were evaluated in a cardiac enzyme study. The bicarbonate-containing solution equilibrated with 100% oxygen becomes highly alkaline as carbon dioxide is released. 95% oxygen and 5% carbon dioxide was added to the crystalloid cardioplegic solution [St. Thomas` Hospital No. 2 Solution] for prevention of severe alkalinity of oxygenated crystalloid cardioplegia. Heart was arrested and reinfused every 20 minutes throughtout the ischemic period with crystalloid cardioplegia or oxygenated crystalloid cardioplegia or blood cardioplegia. Group I was a patient with crystalloid cardioplegia in 11 patients. Group II was a patient with oxygenated crystalloid cardioplegia in 9 patients. Group III was a patient with blood cardioplegia in 15 patients. The value of CK-MB was evaluated from the patient`s serum at 6 hours, 24 hours, and 48 hours postoperatively. In Group I and II, there was no significant change of CK-MB. In Group I and III, the value of CK-MB at postoperative 6 hours was 114$\pm$83 ng/ml and 56$\pm$22 ng/ml [P < 0.05]. In conclusion, blood cardioplegia was superior to crystalloid cardioplegia.

• Journal of Chest Surgery
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• 제26권12호
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• pp.899-903
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• 1993

Possible enhancement of myocardial protection with oxygenated crystalloid cardioplegia and blood cardioplegia were evaluated in a cardiac enzyme study. The bicarbonate-containing solution equilibrated with 100% oxygen becomes highly alkaline as carbon dioxide is released. 95% oxygen and 5% carbon dioxide was added to the crystalloid cardioplegic solution[St. Thomas` Hospital No. 2 Solution] for prevention of severe alkalinity of oxygenated crystalloid cardioplegia. Heart was arrested and reinfused every 20 minutes throughtout the ischemic period with crystalloid cardioplegia or oxygenated crystalloid cardioplegia or blood cardioplegia. Group I was a patient with crystalloid cardioplegia in 11 patients. Group II was a patient with oxygenated crystalloid cardioplegia in 9 patients. Group III was a patient with blood cardioplegia in 15 patients. The value of CK-MB was evaluated from the patient`s serum at 6 hours, 24 hours, and 48 hours postoperatively.In Group I and II, there was no significant change of CK-MB. In Group I and 11I, the value of CK-MB at postoperative 6 hours was 114 + 83 ng/ml and 56 + 22 ng/ml [P [0.05]. In conclusion, blood cardioplegia was superior to crystalloid cardioplegia.

• Restorative Dentistry and Endodontics
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• 제42권2호
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• pp.87-94
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• 2017

Objectives: Chitosan has been widely investigated and used. However, the literature does not refer to the shelf life of this solution. This study evaluated, through the colorimetric titration technique and an analysis of dentin micro-hardness, the shelf life of 0.2% chitosan solution. Materials and Methods: Thirty human canines were sectioned, and specimens were obtained from the second and third slices, from cemento-enamel junction to the apex. A 0.2% chitosan solution was prepared and distributed in 3 identical glass bottles (v1, v2, and v3) and 3 plastic bottles (p1, p2, and p3). At 0, 7, 15, 30, 45, 60, 90, 120, 150, and 180 days, the specimens were immersed in each solution for 5 minutes (n = 3 each). The chelating effect of the solution was assessed by micro-hardness and colorimetric analysis of the dentin specimens. 17% EDTA and distilled water were used as controls. Data were analyzed statistically by two-way and Tukey-Kramer multiple comparison (${\alpha}=0.05$). Results: There was no statistically significant difference among the solutions with respect to the study time (p = 0.113) and micro-hardness/time interaction (p = 0.329). Chitosan solutions and EDTA reduced the micro-hardness in a similar manner and differed significantly from the control group (p < 0.001). Chitosan solutions chelated calcium ions throughout the entire experiment. Conclusions: Regardless of the storage form, chitosan demonstrates a chelating property for a minimum period of 6 months.

• Journal of Biosystems Engineering
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• 제20권4호
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• pp.390-396
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• 1995

This study was conducted to develop a computer simulation program for trickle application of nutrient solution. A computer simulation program using finite element method was developed to evaluate discharges of emitters on trickle application. The uniformity of application for two different lateral line lengths and three application methods was evaluated by the computer simulation program. The results of this study are as follows. 1. A computer simulation program was developed to determine emitter discharges from a trickle application system and pressures at emitter positions by finite element method and to design a uniform trickle application system. 2. The simulation program developed was verified by experiment. The root mean square error between experimental data and simulated data was 1.1% on the average discharge and it was found that the computer simulation program was an effective tool for the design of a trickle application system of nutrient solution. 3. The uniformity of trickle application system was evaluated for three different methods of supplying nutrient solution with different lateral line lengths. The best uniformity was obtained from the method, which supplies nutrient solution from both ends alternatively for the same period of time.

• 보존과학연구
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• 통권19호
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• pp.109-132
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• 1998

According to excavation of Imdang site, these sites were excavated place to a various of sites from Early lron period to the Koryo Kingdom. Artifacts to be conserved were excavated from A, D and E district. Metal artifacts were excavated from D and E district and lacquer ware artifacts were excavated from Adistrict. Metal artifacts including lacquer ware iron sword, imitative bronze mirror, Osujen and bronze artifact with letter and so on. Bronze artifacts were covered with soil and rust and performed consolidation after passivation treatment with Benzotriazole solution. Also, iron artifacts performed desalting treatment with 0.1M sesquicarbonate solution. After desalinization, adhesive of these artifacts were processed with Araldite(rapid type) after consolidation with20%∼30% NAD-10 solution. Lacquer ware artifacts remained fragments of lacquer to be all corroded and soiled. Therefore these artifacts retained its original form. Fragments of lacquer joined with Caparol 1%∼3% solution and the soil of relics coated with PSNY 3%∼6% solution. There were many kinds of lacquer were. Lacquer ware artifacts presumed to a string instrument that provide important clues for lacquer ware research. As for lacquer fragments inquire, paints grain size were $2∼5\mum$ and conformed to vanished three times.

• Journal of Chest Surgery
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• 제33권5호
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• pp.377-384
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• 2000

Background: Numerous studies of safe, long term preservation for lung transplantation have been performed using ex vivo models or in vivo single lung transplantation models. However, a safe preservation time which is applicable for clinical use is difficult to determine. We prepared LPDG solution for lung preservation study. In this study we examined the efficacy of LPDG(low potassium dextran glucose) solution in 24-hour lung preservation by using a sequential bilateral canine lung allotransplant model. Material and Method: Seven bilateral lung transplant procedures were performed using weight-matched pairs(24 to 25kg) of adult mongrel dogs. The donor lungs were flushed with LPDG solution and maintained hyperinflated with 100% oxygen at 1$0^{\circ}C$ for a planned ischemic time of 24 hours for the lung implanted first. After sequential bilateral lung transplantation, dogs were maintained on ventilators for 3 hours: arterial resistance were determined if the recipients hourly after bilateral reperfusion and compared with pretransplant-recipient values, which were used as controls. After 2hours of reperfusion, the chest X-ray, computed tomogram and lung perfusion scan were performed for assessmint of early graft lung function. Pathological examinations for ultrastructural findings of alveolar structure and endothelial structure of pulmonary artery were performed. Result: Five of seven experiments successfully finished the whole assessments after bilateral reperfusion for three hours. Arterial oxygen tension in the recipients was markedly decrased in immediate reperfusion period but gradually recovered after reperfusion for three hours. The pulmonary artery and pulmonary vascular resistance showed singificant elevation(p<0.05 versus control values) but also recovered after reperfusion for three hours(p<0.05 versus immediate period value). The ultrastructural findings of alveolar structure and endothelial structure of pulmonary artery showed reversible mild injury in 24 hours of lung perservation and reperfusion. Conclusion : This study suggests that LPDG solution provides excellent preservation in a canine model in which the dog is completely dependent on the function of the transplanted lung.

• 한국약용작물학회지
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• 제24권3호
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• pp.198-206
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• 2016

Background: Electrical conductivity (EC) and pH are important features of nutrient solution, affecting both growth and quality of crops by altering nutrient uptake. Methods and Results: The pH values of nutrient solutions were controlled at 5.0, 5.5, 6.0, 6.5 and EC values were controlled at 0.68, 0.84, 1.23, 1.41 dS/m. Gingesng root weights were higher during the initial growth period when the plants were treated with low pH and low EC nutrient solutions. However, the higher pH and EC levels, the greater the increase in the rate of root weight between the initial and middle growth periods. The highest ginsenoside amount changed during growth period. The total ginsenoside amount was highest in the root, and the lowest in leaves at 45 and 90 days after treatment, respectively, with solution at a pH of 6.0. After 135 days of treatment, the highest total ginsenoside amount was detected in root treated with soluton with EC values of 1.23 dS/m. Conclusions: For the cultivation of ginseng using a nutriculture system, the pH and EC values of nutrient solutions should to be controlled based on the stage of growth and targeted plant organ (root or leaves).

• Nuclear Engineering and Technology
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• 제18권3호
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• pp.194-199
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• 1986

수용액중에 극미량의 Am의 거동이 pH변화에 따라 변화하는 것을 원심분리법으로 조사하였다. 이 연구에서 평형시간을 2~3주 연장, 방사성 코로이드 형성에 있어서의 시간효과를 조사하였다. 또한 실리카겔 및 Fe$^{3+}$ 등 외부 물질을 첨가하여 그 효과를 조사하였으며, 또한 진한 전해질물질의 효과도 아울러 조사하였다. 그 결과, pH 6에서 Am은 불순입자, 또는 용기벽과 이온 흡착과정으로 급속히 흡착이 일어났다. 외부물질의 첨가는 Am의 흡착을 촉진하였으며, 진한 전해질물질의 첨가로 흡착이 방해되었다. pH 7에서 Am은 pH 6조건과는 전혀 다른 거동을 나타내었다. 일부 Am은 용기 기벽에서 빠른 흡착이 일어났으며, 1~2일 후에 일부는 탈착되었다.

• 대한의생명과학회지
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• 제7권2호
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• pp.91-98
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• 2001

The present study was prospectively designed to assess the clinical effect of leukocyte-depleted blood cardioplegic solution (BCS) on myocardium during cardiac surgery with cardiopulmonary bypass (CPB). 30 adult patients scheduled for elective cardiac surgery were divided into control group (n＝15), which infused routine BCS, and leukocyte-depleted (LD) group (n＝15), which infused leukocyte-depleted BCS. Total and differential leukocyte counts in BCS, malondialdehyde (MDA) and troponin-T (TnT) concentrations in coronary sinus blood, and cardiac index (CI) were measured at preoperative and postoperative period. The BCS in LD group had less total leukocyte counts with neutropenia than that in control group (P＜0.01). MDA (3.70$\pm$0.35 vs 5.90$\pm$0.57 $\mu$mol/L, p<0.05) and TnT (0.42$\pm$0.03 vs 0.60$\pm$0.09 ng/mL, p<0.05) were significantly low in LD group compared with control group, while LD group had higher CI (3.28$\pm$0.16 L/min/$m^2$, p<0.05) than control group (2.69$\pm$0.18 L/min/$m^2$). These results suggest that leukocyte-depleted blood cardioplegic solution has a better myocardial protective effect with less generations of oxygen free radicals and ischemia/reperfusion injury.

• Korea-Australia Rheology Journal
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• 제21권1호
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• pp.47-58
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• 2009

We have investigated the transient behavior of 1D fully developed Poiseuille viscoelastic flow under finite pressure gradient described by the Oldroyd-B and Leonov constitutive equations. For analysis we employ a simple $2^{nd}$ order discretization scheme such as central difference for space and the Crank-Nicolson for time approximation. For the analysis of the Oldroyd-B model, we also apply the analytical solution, which is obtained again in this work in terms of elementary solution procedure simpler than the previous one (Waters and King, 1970). Both models demonstrate qualitatively similar solutions, but their eventual steady flowrate exhibits noticeable difference due to the absence or presence of shear thinning behavior. In the inertialess flow, the flowrate instantaneously attains a large value corresponding to the Newtonian creeping flow and then decreases to its steady value when the applied pressure gradient is low. However with finite liquid density the flow field shows severe fluctuation even accompanying reversals of flow directions. As the assigned pressure gradient increases, the flowrate achieves its steady value significantly higher than its value during oscillations after quite long period of time. We have also illustrated comparison between 1D and 2D results and possible mechanism of complex 2D flow rearrangement employing a previous solution of [mite element computation. In addition, we discuss some mathematical points regarding missing boundary conditions in 2D modeling due to the change of the type of differential equations when varying from inertialess to inertial flow.