• Journal of Korean Ophthalmic Optics Society
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• v.9 no.1
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• pp.145-159
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• 2004

A mathematical model and its computer solution program were proposed to analyze the motion of contact lenses which are being subject to lid-blinking. The equation was derived by incorporating an acceleration induced lid's force exerting on the contact lens, the viscous damping resistance in the tear layer beneath the lens and the sliding frictional force between the lid and the contact lens surface into the formulation of differential equation describing the vibration. The model predicts the time-dependent displacement from the equilibrium postion during/after the blinking. During the blinking, as the time for the completion of one cycle of blinking decreases the off-the-equilibrium displacement of contact lens increases while the decrease of diameter in the contact cause the opposite effect. It is found that lid pressure exerting on the lens cause an insignificant lens displacement from the equilibrium position. After blinking the frequency of damped oscillation of contact lens decreases as the diameter of lens increases, due to the incresed surface while the reduced blinking time does not cause a significant frequency change. This is because that driving force for the contact lens movement posterior to blinking is the capillary-induced force not the lid force.

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.3
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• pp.221-230
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• 2004

In general, remote monitoring systems monitor the status of distributed hosts and/or applications in real-time for diverse managerial purposes. However, most of the extant systems have a few undesirable problems. First of all, they are platform-dependent and are not resilient to network and/or host failures. Moreover, they normally focus on the resource usage trends in monitored hosts, rather than on the status change of the applications running on them. We strongly believe that the latter has more direct and profound effect on the resource usage patterns on each host. In this paper, we present the design and implementation of the Remote Applications Monitoring System (RAMS) that enables us to effectively manage distributed applications through a real-time monitoring of their respective resource usages. The RAMS is a centralized system that consists of many distributed agents and a single centralized manager. An agent on each host is in charge of collecting and reporting the status of local applications. The manager handles agent registration and provides a central access point to the selection and monitoring of distributed applications. The salient features of the system include robustness and portability The adoption of JINI greatly facilitates an automatic recovery from partial network failure and host failure.

• Toxicological Research
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• v.20 no.3
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• pp.251-261
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• 2004

A large number of chemical pollutants including phthalates, alkylphenolic compounds and organochlorine pesticides have the ability to disrupt endocrine function in animals, and alter cog-nitive function. Because hormone mediated events play an important role in central nervous system development and function, the changes in cognitive function seem to be mediated by the endocrine-like action of these chemicals. The present study therefore was designed to investigate effect of bisphenol A (BPA), an endocrine disrupting chemical on neuro-behavial patterns, and expression of estrogen receptors and tyrosine hydroxylase, a limiting enzyme of dopamine synthesis pathway. BPA was treated orally for 3 weeks into 3 week old mice, and then the neuro-behavial patterns (stereo-type behaviors such as jumping rearing and forepaw tremor, climbing behavior, tail flick, rotarod and locomotor activity), and the expression of estrogen receptors and tyrosine hydroxylase were deter-mined every 3 week for 9 weeks. During the treatment of BPA, the food uptake and body weight increase were not significantly changed. BPA resulted in the increased stereotype behaviors (jump-ing, rearing and forepaw tremor) 6 or 9 weeks after treatment. The time response to tail flick and locomotor activity were decreased by the treatment of BPA, whereas the time for rotarod was increased by the treatment of BPA. The expression of estrogen receptor alpha and beta was increased in the brain and pituitary gland. Maximum expression was found in the brain after 9 week of 100 mg/kg BPA treatment and in the pituitary gland after 6 week of 100 mg/kg BPA treatment. Tyrosine hydroxylase was increased in dose and time dependent manners in the brain but no change was found in the pituitary gland. The present data show that exposure of BPA in the young mice could alter expression of estrogen receptors and dopamine synthesis pathway, thereby modulate neuro-behavial patterns (increase of stereotype behaviors but decrease locomotor activity).

• YAKHAK HOEJI
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• v.44 no.3
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• pp.224-231
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• 2000

$Nokyangbotang^{TM}$ (NYBT) is a kind of powerful food for health and have been drunk at a oral dose of 80 ml (99.5 mg) three times per day: It has not been well studied about the anti-fatigue and hepatoprotective activity. In this experiments, we evaluated pathophysiologically the effect of NYBT on swimming time in mouse and hepatoprotective activity in rats intoxicated with carbon-tetrachloride. NYBT was nontoxic in orally acute toxicity test ($LD_{50}$, 320 ml/60 kg): a nontoxic food in more four times of one-shoot dosage (80 ml) to human. Weight-loaded forced swimming test was carried out to measure the swimming time of mice with a 4% load of body weight in plastic cylinder (diameter $10{\;}cm{\;}{\times}{\;}height{\;}20{\;}cm$) on water bath at $25^{\circ}C$, and the anti-fatigue activity represented the ratio of swimming time of experimental group to that of control group. NYBT had dose-dependent anti-fatigue activity Mice administered NYBT at a dose of 320 ml/60 kg once daily for 5 days could swim about two times more than control. Hepatoprotective activities of NYBT were examined by the determination of malonedialdehyde (MDA) and pathological survey in liver and liver function test of rat intoxicated with $CCl_4$ at i.m. dose of 2 ml/kg once daily for 7days. NYBT decreased dose-dependently thiobarbituric acid reactive substance: Oral administration of NYBT at a dose of 20 ml/60 kg was $38.51{\;}{\pm}{\;}3.02$ nmol MDA/g of tissue, that of 80 ml/60 kg was $33.76{\;}{\pm}{\;} 1.84$ nmol MDA/g of tissue, and that of 320 ml/60 kg was $32.87{\;}{\pm}{\;}1.90$ nmol MDA/g of tissue as compared with control group ($43.61{\;}{\pm}{\;}2.85$ nmol MDA/g of tissue). All rats administered NYBT at a dose of 320 ml/60 kg were survival as compared with 40% survival of control animals, and GPT activity of rats administered NYBT at a dose of 80 ml/60 kg was decreased as compared with control. In histopathological survey, NYBT improved slightly the fatty changes of hepatocytes around centrilobular area. These results suggest that NYBT has anti-fatigue and hepatoprotective activity in rats and mice.

• Nutritional Sciences
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• v.9 no.2
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• pp.124-130
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• 2006

To examine the effects of alcohol consumption on body fluid restoration and fat mobilization following exercise induced dehydration, nine healthy collegiate men ($24{\pm}2yrs,\;177{\pm}5cm,\;72{\pm}8kg,\;10.5{\pm}2.3%$ body fat) underwent three experiments. In each experiment, subjects ran on a treadmill to reduce individual body mass to $2.2{\pm}0.1%$ and consumed one of three beverages containing 0, 4, or 8% alcohol over 60 min followed by 4 hr of resting recovery. They consumed approximately 150% of weight loss $(2053{\pm}204,\;2091{\pm}149,\;and\;1943{\pm}295mL)$ and content of alcohol was $9.9{\pm}1.0(0%),\;71.9{\pm}5.1(4%)$, and $132.2{\pm}20.1g$ (8% trial). Body weight, urine volume and samples, blood samples, and thirst sensation were measured five times; at baseline, immediately after exercise, and 0, 1st, and 4th hr of recovery. Blood alcohol concentration after ingestion was $0.0{\pm}0.0(0%),\;0.1{\pm}0.02(4%)$, and $0.2{\pm}0.03%$ (8% trial). No differences in blood sodium and potassium concentrations, and urine specific gravity were noticed over time periods and trials. Thirst sensation tended to be elevated in all trials immediately after exercises and urine output was elevated during the recovery. The magnitude of changes in these variables was proportional to the alcohol concentrations, but not statistically significant. While serum osmolality was not different among trials and time periods in 0 and 4% trials, it was higher during recovery than the baseline in the 8% trial (P<0.01). Triglycerides did not change throughout the time period and among trials. Free fatty acids were elevated after exercise in all trials and 4th hr of recovery in 0% (P<0.05). Subjects' net body fluid balance at 4th hr of recovery was negatively maintained and proportional to alcohol concentrations. Only 8% trials showed a significant reduction at 1st and 4th hr of recovery compared to 0 hr. The results suggested that diuretic effect of alcohol after moderate level of dehydration appeared dose dependent, but beverage containing alcohol up to 4% did not induce impaired rehydration than alcohol free drinks. Alcohol effects on fat mobilization during recovery appeared to be minimal and the mechanism is unclear.

• Journal of Life Science
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• v.24 no.12
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• pp.1284-1290
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• 2014

Fatty acid transporter protein 1 (FATP1) is highly expressed in skeletal muscle and modulates fatty acid uptake and metabolism. However, the influence of insulin-like growth factor-I (IGF-I), a master regulator of skeletal muscle cells, on FATP1 in skeletal muscle cells has not been demonstrated. To investigate the effect of IGF-I on FATP1 and the expression of the IGFBP5 protein, differentiated C2C12 murine skeletal muscle cells were treated with 20 ng/ml of IGF-I at different time points. The results showed that IGF-I increased FATP1 and IGFBP5 protein expression in a time-dependent manner. To determine whether this induction of FATP1 by the IGF-I treatment was regulated pretranslationally, the mRNA level of FATP1 was measured by real-time quantitative PCR. The IGF-I treatment resulted in very rapid induction of the FATP1 mRNA transcript in C2C12 myotubes. FATP1 mRNA increased 169% and 132% after 24 and 48 h of the IGF-I treatment, respectively, and it returned to control levels after 72 h of the treatment, suggesting that the FATP1 gene is regulated pretranslationally by IGF-I in skeletal muscle cells. This is the first evidence that IGF-I can regulate the expression of FATP1. In conclusion, IGF-I induced rapid transcriptional modification of the FATP1 gene in C2C12 skeletal muscle cells and had modulating effects on fatty acid uptake proteins and oxidative proteins.

• Magazine of the Korean Society of Agricultural Engineers
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• v.14 no.1
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• pp.2535-2548
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• 1972

Instead of fertilizing the lands they moved to find other fertile lands and lived a feudal life agriculture and various machincs played a main role in the land reclamation. The best method of land clearing, the time and capacity in the operation and the effect of growing crops should systematically analized prior to the time of 3rd Five-year Economic Development(1972-1976) in order to cultivate 210,000ha of wasteland or the modernization of our country. The present study was investigated to find out a new working-system of mechanical land clearing and development of fertile soil. The results are as follows: 1) The first stage of productive power increases when weeds were mixed soil in the land clearing work in order to supply organic materials and to make soil swollen instead of burning or just removing. 2) The equipments such as bulldozers, harrows, power tillers and so on should be prepared in order to do a systematic work in the land clearing. 3) The work of pulling-up roots is dependent upon the forms of roots spreading under the ground. The work of the pulling-up of the straight roots was most difficult. But before the roots are pulling-up we do not know the forms of roots. 4) The cutting of soil from upside to under side land clearing method (II) Spent 6 hr 7 min 43 sec per 1 Danbo in doing land clearing and control method spent 4 hr 52 min 30 sec per 1 Danbo in doing land cearing. No significant difference could be found between II treatment type and I treatment type. 5) The volume of soil carried by bulldozer $270.38m^3$ per 1 Danbo in I type and in II type, $368.58m^3$ per 1 Danbo or about 36% increased in II type then in I type. But that is not a significant difference when considering the whole productive power of soil. 6) The land clearing of terrace by bulldozers cannot escape making the embankment slope of about $45^{\circ}$, and 25.3% should be decreased in the area. It is recommended to make use of the embankment slope by planting grass for cows. 7) The time of retary tilling increased 2.3 times or 1 hr 42 min 22 sec per 1 Danbo compared to the timesrequired in the harrowing. Because it mixed the Organic matter on ground and the harrowing of subsoil. 8) The havest of pasture growing on the land reclamation in natural slope is as follows. (a) The none fertilizers with reclaimed block of productivity decresed 1/10 than that of the farmland. Therefore the none fer tilizing in the cultivated pasture is unprofitable. (b) The havest of the manured IV treatment block was the best not only in the kinds of fertilizers but also in the kinds of pasture grass.

• Development and Reproduction
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• v.11 no.3
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• pp.219-226
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• 2007

This study was conducted to identify optimistic primordial germ cells'(PGCs) migration activity using heat activated busulfan treatment for the increasing germline chimerism. Donar PGCs viability tests of important conditions for useful germ line chimerism indicated approximately $70{\sim}80%$ viability was time dependent. Transplantation experiments of PGCs into recipient embryos after busulfun treatment, showed the treatment group having 23.5% viability. By comparison, the control group showed 4.8% viability. The 96 hour treatment group and the 118 hour treatment group of the cultured PGCs showed high migration activity. Generally, the transplantation method would consider morphological and physiological characteristics before transplantation. In the present study, the effect of busulfan on migration activity showed viability highest at 53.4% after 48-hour incubation time. However, a previous study showed the best condition for transplantation time to be prior to the 48-hour incubation period, when the chicken embryo does not yet have a developed blood vessel system. In conclusion, an important condition for the production of a transgenic chicken is that most donor PGCs migrate into the recipient embryo without any inhibitory factors. The present results suggest, perhaps by using this modified method of transplantation, it can produce a more efficient chimeric germ line, transgenic chicken.

• Restorative Dentistry and Endodontics
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• v.31 no.3
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• pp.169-178
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• 2006

This study was to verify that the combined application of NaOCl and EDTA was more effective in removal of smear layer than the application of NaOCl alone. furthermore it was aimed to find out the optimal time for the application of EDTA. Thirty five single rooted teeth were cleaned and shaped. NaOCl solution was used as an irrigant during instrumentation. After instrumentation, root canals of the control group were irrigated with 5 ml of NaOCl for 2 minutes. 30 sec, 1 min, and 2 min group were irrigated with 5 ml of 17% EDTA for 30 sec, 1 min, and 2 min respectively. Then the roots were examined with scanning electron microscopy for evaluating removal of smear layer and erosion of dentinal tubule. The results were as follows; 1. The control group: The smear layer was not removed at all. 2. The other groups: 1) $Middle\frac{1}{3}$: All groups showed almost no smear layer. And the erosion occurred more frequently as increasing irrigation time. 2) $Apical\frac{1}{3}$: The cleaning effect of 2 min group was better than the others. The results suggest that 2 min application of 17% EDTA should be adequate to remove smear layer on both $apical\frac{1}{3}\;and\;middle\frac{1}{3}$.

• The Journal of the Korea Contents Association
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• v.18 no.11
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• pp.484-492
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• 2018

This study examined the effects of field complexity and type of target objects on the performance in baggage screening task. A total of 62 participants(male: 45.2%, female: 54.8%) participated and their mean age was 22.88. The simulated baggage screening task was developed for this study and after the orientation and task exercises, main experiment session was conducted. Participants performed a total of 200 tasks and 40(20%) contained target object. The complexity was set at three levels: high, middle, and low levels and the number of background items contained 20, 14. and 8 respectively. The type of target was set as gun, knife, liquid, and righter. The dependent variables were hit ratio and reaction time. The results showed that the hit ratio decreased and reaction time increased significantly as field complexity increased, and they varied depending on the type of target. The hit ratio of the knife was the highest and liquid lowest and reaction time of the knife was the fastest and liquid slowest. In addition, the interaction effect was also significant. Knife was not affected by complexity, however, small item such as lighter was most affected by complexity.