• The Korean Journal of Physiology
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• v.1 no.2
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• pp.169-175
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• 1967

An experiment was designed to see if the hippocampus exerts any influence upon the aggressive behavior of male rats. Fighting between rats was observed for the estimation of aggressiveness. Seventeen rats in which the hippocampus was almost totally removed through a small hole with a diameter around 3 mm made in the neocortex at the boundary between the parietal and occipital lobes (hippocampal group), 8 rats with similar neocortical damage alone (operated control group), and 17 normal control rats (normal group) were prepared and subjected to the experiment 3 months after the operation. Applying electric shock of short duration to the feet in a box with grid floor, a fight was provoked between an animal belonging to the hippocampal group and one belonging to the nor-mal group, between a rat of the hippocampal group and one of the operated control group, and also between a rat of the operated control group and one of the normal group. Three observers judged the performance of each animal independently and described it as winning, defeated, tied, or non-fighting. Fifteen shocked trials were administered to each pair of animals with around 2 minutes' interval between each trial. An animal received a 'judging score' of 3 when it won more frequently than was defeated, a judging score of 2 when it won as frequently as was defeated, when all fights were tied, or when no fighting occurred, while it received a judging score of 1 when it won less frequently than was defeated. Group differences in performances were analyzed in terms of judging score using Kolmogorov-Smirnov test for one sample. The results obtained were as follows: 1. In the fights between the hippocampal and the normal groups, the hippocampal animals made significantly better judging scores than the normal animals did (Table 1). 2. There was no significant difference between the hippocampal and the operated control group as to the judging scores they made in the course of fights between the two groups. However, the hippocampal animals tended to dominate over the operated control group as judged by comparing the total 'winning' of the former (30) to that of the latter (14) (Table 2). 3. The total judging score made by the operated control group in the course of the fights against the normal group was not significantly superior to that made by the normal group (Table 3). It was inferred from the above results that, though inconspicuous, the hippocampus tended to exert an inhibitory influence upon the aggressive behavior of male rats.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.1
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• pp.51-57
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• 2009

Biofouling in seawater reverse osmosis (SWRO) desalination process causes many problems such as flux decline, biodegradation of membrane, increased cleaning time, and increased energy consumption and operational cost. Therefore biofouling is considered as the most critical problem in system operation. To control biofouling in early stage, detection of the most problematic bacteria causing biofouling is required. In this study, six model bacteria were chosen; Bacillus sp., Flavobacterium sp., Mycobacterium sp., Pseudomonas aeruginosa, Pseudomonas fluorescens, and Rhodobacter sp. based on report in the literature and phylogenetic analysis of seawater intake and fouled RO membrane. The adhesion to RO membrane, the high pressure resistance, and the hydrophobicity of the six model bacteria were examined to find out their fouling potential. Rhodobacter sp. and Mycobacterium sp. were found to attach very well to RO membrane surface compared to others used in this study. The test of hydrophobicity revealed that the bacteria which have high hydrophobicity or similar contact angle with RO membrane ($63^{\circ}$ of contact angle) easily attached to RO membrane surface. P. aeruginosa which is highly hydrophilic ($23.07^{\circ}$ of contact angle) showed the least adhesion characteristic among six model bacteria. After applying a pressure of 800 psi to the sample, Rhodobacter sp. was found to show the highest reduction rate; with 59-73% of the cells removed from the membrane under pressure. P. fluorescens on the other hand analyzed as the most pressure resistant bacteria among six model bacteria. The difference between reduction rates using direct counting and plate counting indicates that the viability of each model bacteria was affected significantly from the high pressure. Most cells subjected to high pressure were unable to form colonies even thought they maintained their structural integrity.

• Journal of Chest Surgery
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• v.19 no.1
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• pp.35-42
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• 1986

Prevention of thrombombolism after rosthetic cardiac valve replacement is essential for the patients. About 90% of patients are free of major and minor thromboembolic complications 5 year after replacement of cardiac valves with prosthetic devices when they are under control of anticoagulant therapy. Ticlopidine is a drug that alter platelet function to have an antithrombotic effect. It is an antiaggregating agent which inhibits primary platelet function to have an antithrombotic effect. It is an antiaggregating agent which inhibits primary platelet aggregation induced by ADP and increases the production of prostaglandin $D_{2}$. Aspirin in small doses inhibits platelet synthesis of prostaglandins by irreversibly blocking the enzyme cyclo-oxygenase. Platelet secretion and aggregation are impaired with Ticlopidine and Aspirin. the thromboembolic event sof 54 patient s who were treated with Ticlopidine and Aspirin after cardiac valve replacement were evaluated and compared with that of 79 patients who were treated with Wafarin and Aspirin after the same type of operation. The follow-up period ranged from 4 to 110 months (mean of 48 months). there were 11 major thromboembolic episodes including three deaths in the warfarin goup during mean follow-up period of 56 months. two cases of CVA and one hemoarthrosis were noted due to overdose of Warfarin. Inticlopidine group, there was only one fatal thromboembolic epdisode three month after mitral valve replacement during mean follow-up period of 18 months. Two episodes of hypermenorrhea resulting anemia ere noted in the ticlopidine group. We measured the parameters of platelet function in aggreagation curve of platelet with platelet aggregometer (chrono-log Aggregometer, Model No. 430) Aggregation test was performed with three final concentrations of epinephrine in 10 uM/L, ADP in 5uM/L. 28 patients with prosthetic cardiac valves and 35 healthy volunteers were subgrouped as follows to analyze the effect of antithrombotic drugs used. Group I ; 11 patients treated with 250-500 mg of ticlopidine and 0.5gm of Aspirin as a daily single dose after cardiac valve replacement (14 St. Jude Medical and 1 Carpentier-Edwards, 9 patients with atrial fibrillation among them) Group II ; 10 patients treated with 3-5 mg of Warfarin and 0.75 gm of Aspirin daily to prolong prothrombin time around 20 seconds for more than 6 months and single Aspirin dose was maintained afterward as a life-long regimes(3 St. Jude Medical, 1 Hall-Kaster and 7 Carpentier-Edwards valve, 9 patients in atrial fibrilation). Group III ; 7 patients who quit anticoagulant treatment (Warfarin + Aspirin) 6-12 months after the regime as group II (3 St. Jude Medical. 1 bjork-Shiley, 1 Hall-Kaster, 3 Carpentier-Edwards valve, 2 of them are with atrial fibrillation). Group IV ; 35 healthy vounteers (28 males and 7 females). The following results were obtained. 1. The mean maximal platelet aggregability in Group I induced by 10uM/L epinephrine was 15.6%, and 17.5 and 18.7% in BM in proportion to the induction by 5 and 10 uM/L ADP. 2. The mean maximal platelet aggregability in Group II induced by 10uM/L epinephrine was 16.5%, and 27.4 and 44.7% in BM in proportion to the induction by 5 and 10uM/L ADP. 3. The mean maximal platelet aggregability in group III induced by 10uM/L epinephrine was 65%, and 56.5 and 51.8% in BM in proportion to the induction by 5 and 10 uM/L ADP. 4. The mean maximal platelet aggregability in the normal subjects induced by 10 uM/L epinephrine was 64%, and 65 and 69% in Bm inproportion to the induction by 5 and 10 uM/L ADP. 5. Reversible change of platelet aggregation curve induced by 5 and 10uM/L was noted all of the patients in Group I. conclusion : Ticlopidine is an antiaggregating agent which inhibits primary platelet aggregation induced by ADP, and increases the production of prostaglandin $D_{2}$. Ticlopidine and Aspirin produced a significant inhibition of platelet in the presence of ADP and epinephrine in our study. Acccording to our brief experience, 250 mg of ticlopidine and low dose of Aspirin resulted synergistic superior effect to each drug alone in prevention of thromboembolism after prosthetic cardiac valve replacement.

• Journal of Chest Surgery
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• v.32 no.9
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• pp.806-812
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• 1999

Background: Selection of reconstruction route in esophageal cancer surgery is based on the patient's status, characteristics of tumor, surgeon's preference and experience. Of the various routes, it has been documented that subcutaneous or substernal route may prolong operation time and may be vulnerable to postoperative respiratory complications. This study was designed to evaluate whether the selection of reconstruction route affects the surgical outcomes. Material and Method: Of 131 patients who have undergone resection and reconstruction for esophageal cancer, posterior mediastinal route(Group I, n=34), substernal route (Group II, n=31), and subcutaneous route(Group III, n=21) were retrospectively reviewed in 86 patients. Results of early operations and morbidities were compared between the groups. Result: There was a male prevalence(79 of males vs. 7 of females). There were 81 squamous cell cancers and 5 adenocarcinomas. There were no differences between groups in weight, height, age, cancer staging and location, and in the preoperative anesthetic risk evaluation and pulmonary function test(p=NS). Postoperative mechanical ventilation time was longer in Group I(20.6 hours) than in Group II(7.8 hours) or III(3.4 hours)(p=0.005). Duration of stay in the intensive care unit was prolonged in Group III(6.4 days) compared to Group I (3.9 days) or II(3.1 days)(p=0.043). No differences were noted in the duration of hospital stay between the groups(p=NS). Blood transfusion was needed in 30 out of 34 patients in Group I compared to 14/31 in Group II or 15/21 in Group III(p=0.001). The mean amount of transfusion for each patient was also higher in Group I(3,833 mL) than in Group II(1535 mL) or Group III(1419 mL)(p=0.04), but there was no difference in the inreoperation due to bleeding. Ea ly mortality rate was substantially higher in Group I(17.6%) but the differences between the groups were insignificant(p=NS). Although sepsis was a more prevalent cause of death in Group I, it was not related to anastomotic leak. Other morbidities did not differ between the groups(p=NS). Conclusion: In above results show that the reconstruction route does not affect the outcome of esophageal cancer surgery. We believe that the selection of reconstruction route can be based on the surgeon's preference and experience.

• Journal of Chest Surgery
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• v.31 no.5
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• pp.456-465
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• 1998

Cardiopulmonary bypass(CPB) in children is associated with the accumulation of body water after cardiac operation, as a consequence of an inflammatory capillary leak. Following work by Elliott in 1991, modified ultrafiltration(MUF) was introduced after bypass as a means of hemoconcentrating patients and a potential way of removing water from the tissues. We have carried out a prospective randomized study of 20 children undergoing open heart surgery, comparing MUF with nonfiltered controls. MUF was carried out for a mean of 18.9 minutes after completion of CPB to a hematocrit of 37.1%(mean). The mean water volulme removed by the ultrafiltration was 38.4 ml/kg and the mean blood volume retransfused from the oxygenator during the ultrafiltration was 32.1 ml/kg. Fluid balance, hemodynamics, hematocrit, osmolarity and dosage of drug treatment were recorded for 4∼12 hours postoperatively. The results were analyzed using Student t-test and ANOVA, comparing controls(n=10) to MUF(n=10). Blood loss(ml/kg/24hr) was 14.5(mean) in MUF versus 13.7 in controls; blood transfused(ml/kg/24hr) 6.6 in MUF versus 15.2 in controls; plasma transfused(ml/kg/24hr) 65.7 in MUF versus 59.6 in controls. There was rise in arterial blood pressure and hematocrit during MUF. Percent rise of systolic blood pressure was 28.8% in MUF versus 18.7% in controls(p=0.366); percent rise of diastolic blood pressure was 28.8% in MUF versus 8.5% in controls(p=0.135); and percent rise of mean blood pressure was 36.2% in MUF versus 8.2% in controls (p=0.086). Percent rise of hematocrit was 40.0% in MUF versus 23.5% in controls(p=0.002). There was no significant difference in the inotropic requirement and the postoperative serum osmolarity between two groups. The number of days on the ventilator, the duration of stay in the intensive care unit, and the postoperative hospital stay were not significantly different between the two groups.

• Fire Science and Engineering
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• v.31 no.5
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• pp.53-62
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• 2017

Electric power which is the energy source of economy and industries requires long distance transportation due to regional difference between its production and consumption, and it is supplied through the multi-loop transmission and distribution system. Prior to its actual use, electric power flows through several transformations by voltage transformers in substations depending on the characteristics of each usage, and a transformer has the structure consisting of the main body, winding wire, insulating oil and bushings. A transformer fire that breaks out in substations entails the primary damage that interrupts the power supply to houses and commercial facilities and causes various safety accidents as well as the secondary economic losses. It is considered that causes of such fire include the leak of insulating oil resulting from the destruction of bottom part of bushings, and the chain reaction of fire due to insulating oil that reaches its ignition point within 1 second. The smoke detector and automatic fire extinguishing system are established in order to minimize fire damage, but a difficulty in securing golden time for extinguishing fire due to delay in the operation of detector and release of gas from the extinguishing system has become a problem. Accordingly, this study was carried out according to needs of active mechanism to prevent the spread of fire and block the leak of insulating oil, in accordance with the importance of securing golden time in extinguishing a fire in its early stage. A bushings fireproof structure was developed by applying the high temperature shape retention materials, which are expanded by flame, and mechanical flame cutoff devices. The bushings fireproof structure was installed on the transformer model produced by applying the actual standards of bushings and flange, and the full scale fire test was carried out. It was confirmed that the bushings fireproof structure operated at accurate position and height within 3 seconds from the flame initiation. It is considered that it could block the spread of flame effectively in the event of actual transformer fire.

• Journal of The Korean Ophthalmological Society
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• v.59 no.11
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• pp.1017-1023
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• 2018

Purpose: A recently introduced phacoemulsification system, the WhiteStar $Signature^{(R)}$ PRO, has demonstrated improved nucleus followability and cutting efficiency via an improved pump regulator with a higher reaction response and an automatic occlusion sensing system. In this study, we compared various phacoemulsification parameters between the new system and an older version of the device. Methods: A total of 80 eyes of 68 patients with cataracts who had undergone phacoemulsification by a single surgeon were included in this study. Forty eyes of patients underwent phacoemulsification using the older $Signature^{(R)}$ system (WhiteStar); these patients were classified as the control group. Another 40 eyes of patients underwent phacoemulsification with the newer enhanced system, the WhiteStar $Signature^{(R)}$ PRO; these patients were assigned to the experimental group. During the operation, operative parameters, including the effective phaco time (parameter of effective phaco time with a specific coefficient for the transversal movement expressed in seconds, EFX), ultrasound time (seconds [s]), effective phacoemulsification time (EPT, s), average phacoemulsification power (AVG, %), and balanced salt solution usage, were measured to determine the performance enhancement offered by the updated system. Central corneal thickness was measured before and after surgery to compare corneal edema. The relationships between the two groups were analyzed using an independent t-test. Results: The Signature $PRO^{(R)}$ system showed a lower EFX (p < 0.001), a shorter EPT (p < 0.001), and a smaller AVG (p < 0.001). Postoperative corneal thickness did not differ significantly between the two groups. Conclusions: Comparing the efficacy of the improved reaction speed of the device and automatic occlusion sensing system in performing phacoemulsification, the updated Signature $PRO^{(R)}$ system demonstrated superior followability and cutting efficiency regardless of nuclear cataract hardness.

• Journal of Technology Innovation
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• v.28 no.4
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• pp.1-26
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• 2020

Due to the spread of Corona 19 around the world, Infectious Disease Medicine and New Medical Devices such as Diagnostic Agent are being rapidly developed and launched, and for the fast supply and demand of these, each country has eased import regulations or has implemented policies for fast approval(NIDS, 2020). On the other hand, New Developed Medical Devices that are not related to New Infectious Diseases, they are still entering the market through strict licensing and licensing regulations, such as delay and cancellation in the test inspection process, etc. Therefore, This Study specialized in the government-managed laws encountered when New Medical Devices enter the market, derive Factors influencing the Strength of Regulations, analyzes the Strength of Regulations, and proposes a Regulatory Response Framework. The Research Method was conducted by Literature Research, was applied by Failure Mode and Effects Analysis(FMEA) Method, Expert Interview(1st): Idea Collection, Expert Interview(2nd): Validation, and Priority through the Application Process of FMEA Method. A Method of Quantifying the Intensity of Regulation was proposed by multiplying the Impact of the Influencing Factors for each stage of regulation and the Burden Impact for each type of Regulatory Affairs to find the Importance of the Regulatory Factors and multiplying the Severity of the Regulatory Impact. The Implications are that major overseas countries and the Korean government are actively responding with Special Regulatory Policies and Mitigation Policies for fast licensing of New Developed Medical Devices in accordance with Corona 19. It is expected that the direction for improvement of regulations and measures to respond to regulations will be implemented so that a more proactive and preemptive response to the regulatory process of the licensing policy for New Devices can be achieved.

• Journal of the Korean Society of Radiology
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• v.13 no.2
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• pp.261-270
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• 2019

The separation permeation characteristics of $N_2-O_2$ gas in air at cell membrane model of skin which irradiated by high energy electron(linac 6 MeV) were investigated. The cell membrane model of skin used in this experiment was a sulfonated polydimethyl siloxane(PDMS) non-porous membrane. The pressure range of $N_2$ and $O_2$ gas were appeared from $1kg_f/cm^2$ to $6kg_f/cm^2$. In this experiment(temperature $36.5^{\circ}C$), the permeation change of $N_2$ and $O_2$ gas in non-porous membrane by non-irradiation were found to be $1.19{\times}10^{-4}-2.43{\times}10^{-4}$, $1.72{\times}10^{-4}-2.6{\times}10^{-4}cm^3(STP)/cm^2{\cdot}sec{\cdot}cmHg$, respectively. That of $N_2$ and $O_2$ gas in non-porous membrane by irradiation were found to be $0.19{\times}10^{-4}-0.56{\times}10^{-4}$, $0.41{\times}10^{-4}-0.76{\times}10^{-4}cm^3(STP)/cm^2{\cdot}sec{\cdot}cmHg$, respectively. The irradiated membrane was significantly decreased about 4-10 times than membrane which was not irradiated. And ideal separation factor of $N_2$ and $O_2$ gas by non-irradiation was found to be from 1.32 to 0.42 and that of $N_2$ and $O_2$ gas by irradiation was found to be from 0.237 to 0.125. The irradiated membrane was significantly decreased about 4-5 times than membrane which was not irradiated. When the operation change(cut) and pressure ratio(Pr) by non-irradiation were about 0, One was increased to the oxygen enrichment and the other was decreased to the oxygen enrichment. The irradiated membrane was significantly decreased about 4-19 times than membrane which was not irradiated. As the pressure of $N_2$ and $O_2$ gas was increased, the selectivity was decreased. As separation permeation characteristics of $N_2-O_2$ gas in cell membrane model of skin were abnormal, cell damages were appeared at cell.

• Journal of Korean Home Economics Education Association
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• v.32 no.4
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• pp.81-101
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• 2020

The purpose of this study is to develop and implement a process-based evaluation program with the theme of school space design in the housing area of the middle school home economics. In order to achieve For thispurpose, a process-based evaluation program based on the theme of school space design was developed following the ADDIE instructional design model, and the program was executed to a total of 93 students. A questionnaire survey and in-depth interview were conducted for the evaluation of the program. The results of this study are as follows. First, based on the results of a 2015-Revised Curriculum analysis, a school space design program evaluation plan was established, and two evaluation tasks were developed. Accordingly, scoring criteria were prepared and 8 evaluation materials for students and 2 evaluation materials for teachers were developed. A total of 9 sessions were developed for teaching and learning activities and evaluation-linked operation procedures to perform evaluation tasks. As a result of an expert validity test for the program, all items were verified to be appropriate in content validity and content composition with an average of 3.6 to 4 points (4 points). Second, after conducting the school space design program, a survey on students were conducted, and as a result, all three areas of school space design class, process-based evaluation, interest scored high in average scores of 4.12 to 4.27 out of 5. According to the survey and interview results, the program provided new learning opportunities for school space design, the students were able to reach the suggested achievement goals, and the self-assessment, peer evaluation and teacher feedback positively affected the students during the learning process so that they could reflect on their learning and actively participate in the subsequent learning activity. This study has a limitation in generalizability in that the program was conducted on a limited number of students, and future studies are expected to expand the scope in terms of research participants, evaluation criteria, and school space design classes. This study laid the foundation for theory and practice by developing and implementing a process-based evaluation program for home economics education, and it has contribution in that it suggested the possibility that teachers and students can take the initiatives in school space design, focusing on the housing content elements of home economics.