• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.4
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• pp.38-46
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• 2008

An object of this study is to understand the correlation between the characteristics of an engine performance and combustion characteristics, applying BD20 fuel reformed by ultrasonic energy irradiation to diesel engines. Before conducting the main experiment, an experiment was performed to determine the optimum injection timimg of reformed BD20 by ultrasonic energy irradiation. To control the duration of the ultrasonic energy irradiation, the capacity of an ultrasonic energy fuel supply system was tested with 550cc and 1100cc chambers. As the result of the analysis of the regular BD20 and reformed BD20 by ultrasonic energy irradiation, the BSFC and the Power of the reformed BD20 was improved 3% and 6%, respectively compared to those of non-irradiated BD20. When the fuel injection timing was delayed by $5^{\circ}$, the engine power was improved by 3%, and the BSFC was improved by 2%. The maximum cylinder pressure of reformed BD20 was improved by a maximum of 6% in comparison to that of regular BD20, and demonstrated a synergistic effect of 3% by delaying the injection timing $5^{\circ}$.

• Journal of ILASS-Korea
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• v.27 no.2
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• pp.84-93
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• 2022

To implement carbon-neutrality in transportation sectors until 2050, hydrogen is considered a promising fuel for internal combustion engines because hydrogen does not contain carbon itself. Although hydrogen does not emit CO₂ emission from its combustion process, the low energy density in a volume unit hinders the adoption of hydrogen. Therefore, the understanding of hydrogen jet behavior and measurement of equivalence ratio must be conducted to completely implement the high-pressure hydrogen direct injection. The main objective of this research is feasibility test of hydrogen local equivalence ratio measurement by laser-induced breakdown spectroscopy (LIBs). To visualize the macroscopic structure of hydrogen jet, high-speed schlieren imaging was conducted. Moreover, LIBs has been adopted to validate the feasibility of hydrogen local equivalence ratio measurement. The hydrogen injection pressure was varied from 4 MPa to 8 MPa and injected in a constant volume chamber where the ambient pressure was 0.5 MPa. The increased injection pressure extends the vertical penetration of hydrogen jet. Due to the higher momentum supply when the injection pressure is high, the hydrogen has easily diffused in all directions. As the laser trigger timing has delayed, the low hydrogen atomic emission was detected due to the longer mixture formation time. Based on equivalence ratio measurement results, LIBs could be applied as a methodology for hydrogen local equivalence ratio measurement.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.15 no.1
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• pp.343-355
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• 2002

Background : Although Samsoeum has been used frequently on allergic rhinitis, but there isn't any experimental research for that. Objective : This study was performed to investigate the anti-allergic effects of Samsoeum and Samsoeumgamibang. Materials and Methods : Katayama's method was used to observe the vascular permeability response induced by serotonin and histamine. Muller's method was used to observe the contact dermatitis response induced by picryl chloride. Miller's method was used to observe the delayed type hypersensitivity response to SRC. Results : 1. In the vascular permeability response to intradermal injection of serotonin, 2,600mg/kg, p.o. group of Samsoeum(蔘蘇飮), 1,300 and 2,600mg/kg, p.o. group of Samsoeumgamibang(蔘蘇飮加味方) showed significant inhibitory effects on the leakage of Evan's blue solution. 2. In the vascular permeability response to intradermal injection of histamine, 1,300 and 2,600mg/kg, p.o. group of Samsoeum, also 1,300 and 2,600mg/kg, p.o. group Samsoeumgamibang showed significant inhibitory effects on the leakage of Evan's blue solution. 3. In the contact dermatitis response induced by picryl chloride, 1,300 and 2,600mg/kg, p.o. group of Samsoeum, 1,300 and 2,600mg/kg, p.o. group of Samsoeumgamibang showed significant inhibitory effects on ear swelling formation. 4. In the delayed type hypersensitivity response to SRC. 2,600mg/kg, p.o. group of Samsoeum and 2,600mg/kg, p.o. group of Samsoeumgamibang showed significant inhibitory effects on foot swelling. Conclusion : This study shows that Samsoeum and Samsoeumgamibang may have anti-allergic effects. So Samsoeum and Samsoeurngamibang can be helpful to treat allergic rhinitis.

• Korean Journal of Head & Neck Oncology
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• v.17 no.2
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• pp.174-178
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• 2001

Background and Objective: Percutaneous ethanol injection therapy has been used in the treatment of the benign thyroid diseases. Although the reported side-effects of the therapy was mild and transient, some side-effects including local or radiating pain are troublesome to the patients. Radioactive iodine-131($Ra-^{131}I$) also has been effectively and safely used for management of the benign thyroid diseases. So we developed the percutaneous intranodular injection therapy of $Ra-^{131}I$ as an alternative of percutaneous ethanol injection therapy. Materials and Methods: From December 1998 to October 1999, we treated 29 outpatients (25 women and 4 men, mean age: $47{\pm}12$ years). Inclusion criteria were follows; age >30 years, cytologically benign, with normal thyroid function, cold nodule on thyroid scintigram, solid or mixed natured nodules in sonographical evaluation. Nodular volume was estimated by sonography according to the ellipsoid formula. $Ra-^{131}I$(0.1mCi/ml) was administered in a single dose injection. Follow-up studies every 3 months consisted of full history, thyroid function test, and sonography. We determined the therapeutic response is effective if the volume reduction of the nodule occurred above 30%. Results: After at least 3 months follow-up, 11 patients showed effective response, 12 patients showed minimal or unchanged response and 6 patients showed progression. Although side-effects such as injection pain, febrile reaction, and hormonal changes were absent, an infectious complication in injection site was developed from 1 case. Conclusion: Although we need a more prolonged follow-up to evaluate the delayed sequelae, we can suggest that percutaneous intranodular injection therapy of $Ra-^{131}I$ may be an attractive non-surgical treatment in selected cases of benign thyroid nodules.

• Clinical and Experimental Pediatrics
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• v.61 no.5
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• pp.150-155
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• 2018

Purpose: Infantile spasms, also known as West syndrome, is an age-specific epileptic seizure. Most patients with this condition also exhibit delayed development. This study aimed to determine the effect of long-term prenatal stress on susceptibility to infantile spasms. Methods: We subjected pregnant rats to acute or chronic immobilization stress. Resulting offspring received N-methyl-D-aspartic acid (15 mg/kg, intraperitoneally) on postnatal day 15, and their behaviors were observed 75 minutes after injection. The expression of KCC2 and GAD67 was also determined using immunohistochemistry. Results: Exposure to long-term prenatal stress increased the frequency of spasms and decreased the latency to onset of spasms compared with offspring exposed to short-term prenatal stress. Expression of KCC2 and GAD67 also decreased in the group exposed to long-term prenatal stress compared with the group exposed to short-term prenatal stress. Conclusion: Our study suggests that exposure to long-term prenatal stress results in increased susceptibility to seizures.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.4
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• pp.400-406
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• 2019

We report a 12-month-old female infant who had a history of neonatal sepsis with liver micro-abscesses that resolved with intravenous antibiotics during neonatal period. During her neonatal admission period, no umbilical vein catheter was inserted. Also, she did not undergo any abdominal surgeries or had a postnatal history of necrotizing enterocolitis. However, the child developed upper gastrointestinal bleeding in form of hematemesis and melena secondary to esophageal varices at the age of 12 months with an extra-hepatic portal vein obstruction with cavernous transformation and portal hypertension subsequently. The child underwent a successful endoscopic injection sclerotherapy. She is now 20-month-old and has portal hypertension but otherwise asymptomatic. We are proposing the possibility of a delayed-onset portal hypertension as a complication of liver abscess and neonatal sepsis.

• Journal of Embryo Transfer
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• v.17 no.1
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• pp.13-21
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• 2002

Intracytoplasmic Sperm Injection (ICSI) has been widely used fur both human infertility and basic research. However, the high incidence of chromosomal abnormality is severe problem in cattle. Various oocyte activation stimuli, therefore, were compared by assessment of developmental capacity and chromosome analysis. Motile sperm selected by Percoll-density gradient were treated with 5 mM dithiothreitol (DTT) and injected into an oocyte matured fur 24 h. Eggs were then allocated into 5 treatment groups. Group 1 (control), sperm injection was performed without any further activation stimuli to the oocytes. Group 2 (handled control), sham injection was performed without sperm. In Group 3, oocytes exposed to 5 (M ionomycin for 5 min at 39(C. Group 4. ionomycine + 1.9 mM demethylaminopurine (DMAP, 3 h) and Group 5, ionomycine + 3 h culture in Ml99 + DMAP. Cleavage and the later development rate in Groups 1, 2 and 3 were significantly (P<0.05) lower than those in Groups 4 and 5. The incidence of chromosomal abnormality in the embryos treated directly with DMAP after ionomycine was relatively higher than in the embryo of Group 3 h, delayed DMAP treatment. From this results DMAP caused to be arrested the release of the 2nd polar body, resulting in changes of chromosomal pattern. Therefore, the time interval between ionomycin and DMAP is a crucial role in bovine ICSI.

• The Korean Journal of Pharmacology
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• v.8 no.2
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• pp.27-34
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• 1972

The present study is concerned with the demonstration of the influence of long term treatment with caffeine and phenobarbital on pentobarbital sleeping time, gastric secretion, increase rate of body weight and brain and liver weight in rats. The experimental subjects were rats weighing about 140 to 150 g, each of them was isolated in a separate cage. Each group was given 1 ml normal saline solution as control, caffeine 10 mg/kg and phenobarbital 30 mg/kg as experimental groups. All drugs were injected intraperitoneally, daily for 4 weeks. The results obtained are summarized as follows; 1. There was significant difference between before and after injection of drugs (caffeine citrate 10 mg/kg and phenobarbital 30 mg/kg) on pentobarbital sleeping time. The sleeping time of caffeine treated group was delayed (22.4%, p<0.01) significantly compared with that of before injection. The sleeping time of phenobarbital treated group was markedly shortened (93.6%, p<0.001) compared with that of before injection of drugs. 2. The volume, free and total acidity and pH of gastric juice determined five hours after pyloric ligation in fasting rats were not significantly changed in experimental groups compared with control group. However the volume of gastric juice was increased 25% in both caffeine and phenobardital treated group. 3. The increased ratio of body weight revealed no remarkable difference compared with intial body weight. However, caffeine treated group showed markedly increased body weight after first and second week of injection. 4. The brain and liver weight in experimental group showed no significant difference compared with control group (as percentage of body weight).

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.2061-2068
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• 2015

Background: Tumors are largely unable to metabolize ketone bodies for energy due to various deficiencies in one or both of the key mitochondrial enzymes, which may provide a rationale for therapeutic strategies that inhibit tumor growth by administration of a ketogenic diet with average protein but low in carbohydrates and high in fat. Materials and Methods: Thirty-six male BALB/C nude mice were injected subcutaneously with tumor cells of the colon cancer cell line HCT116. The animals were then randomly split into three feeding groups and fed either a ketogenic diet rich in omega-3 fatty acids and MCT (MKD group; n=12) or lard only (LKD group; n=12) or a standard diet (SD group; n=12) ad libitum. Experiments were ended upon attainment of the target tumor volume of $600mm^3$ to $700mm^3$. The three diets were compared for tumor growth and survival time (interval between tumor cell injection and attainment of target tumor volume). Results: The tumor growth in the MKD and LKD groups was significantly delayed compared to that in the SD group. Conclusions: Application of an unrestricted ketogenic diet delayed tumor growth in a mouse xenograft model. Further studies are needed to address the mechanism of this diet intervention and the impact on other tumor-relevant parameters such as invasion and metastasis.

• Journal of Environmental Science International
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• v.26 no.2
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• pp.249-256
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• 2017

In this study, we evaluated the potential of 70% ethanol extract from Persicaria nepalensis (PNE) as a cosmetic ingredient by primary skin irritation, ocular irritation, and maximization tests for delayed hypersensitivity in New Zealand white rabbits and Hartley guinea pig. Skin safety study was performed to evaluate the potential toxicity of PNE using the primary irritation test. In the primary irritation test, 50% PNE was applied to the skin, and no adverse reactions such as erythema and edema were observed at the intact skin sites. Therefore, PNE was classified as a practically non-irritating material based on a primary irritation index of "0.0.". In the ocular irritation test, the 50% PNE applied did not show any adverse reactions in the different parts of rabbit eyes, including the cornea, iris, and conjunctiva. Thus, PNE was classified as a practically non-irritating material based on an acute ocular irritation index of "0.0.". Skin sensitization was tested by the Guinea Pig Maximization Test (GPMT) and Freund's Complete Adjuvant (FCA) using an intradermal injection of 10% PNE. Edema and erythema were not observed 24 and 48 h after the topical application of PNE in skin sensitization test, which exhibited a sensitization score of "0.0.". Therefore, it can be suggested that P. nepalensis could be used as potential candidates for cosmoceutical ingredients, without any major side effects.