• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.6
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• pp.611-615
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• 2015

Anti-aircraft gun system is used for low-level air defense system and has more than twin guns with high firing rate in order to maximize the capability of defense. Gun's vibration and bullet's variance has a critical effect on accuracy and hit probability of weapon system such as anti-aircraft gun system with high firing rate. Typical mechanism to reduce the amount of vibration and shock during gun-fire process is very important design factor. In this paper, the suspension characteristics of the vehicle are studied for the improvement of isolating performance of gun firing system with high firing rate. Gun fire test for the vehicle is conducted and computational models using Recurdyn and Adams are created based on test results. Through this study, results of computational analysis are compared with the real test results, which includes type, location and quantity of suspension and gun mechanism are selected for anti-aircraft gun. From the result of this study, we could make basic design and consider the proper component of the system such as suspension and gun spring.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.50-50
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• 2003

We have identified and analysed a putative response regulator two-component gene (CaSKN7) from Candida albicans and its encoding protein (CaSkn7). CaSKN7 has an open reading frame of 1677bp. CaSKN7 encodes a 559 amino acid protein (CaSkn7) with an estimated molecular mass of 61.1 kDa. CaSKN7 is a homologue of a Saccharomyces cerevisiae SKN7 that is the regulator involved in the oxidative stress response. To study the role of CaSKN7, we constructed a CAI4-derived mutant strain carrying a homozygous deletion of the CaSKN7 gene. In the caskn7 disruptant cells, the formation of germ tube require shorter time than that in the congenic wild-type strain but the growth of mycelium delayed in liquid media. In contrast, the caskn7 disruptant cells attenuate the differentiation in solid media and the virulence in mouse model system. Expression level of hypha-specific and virulence genes - HYR1, ECE1, HWP1, and ALS1 - in the caskn7 disruptant cells increased as compared with that in the congenic wild-type strain in 10％ serum YPD. Skn7 in 5. cerevisiae was found to bind the HSE element from the SSA promoter, Also, CaSkn7 contains heat shock factor DNA-binding domain and the promoters of these genes have HSE-like sties. Therefore these results show that CaSKN7 regulate the differentiation and virulence of C. albicans.

• Tuberculosis and Respiratory Diseases
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• v.41 no.5
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• pp.452-461
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• 1994

Background: Tumor necrosis factor(TNF)-$\alpha$ and Interleukin(lL)-$1{\beta}$ are thought to play a major role in the pathogenesis of the septic syndrome, which is frequently associated with adult respiratory distress syndrome(ARDS). In spite of many reports for the role of TNF-$\alpha$ in the pathogenesis of ARDS, including human studies, it has been reported that TNF-$\alpha$ is not sensitive and specific marker for impending ARDS. But there is a possibility that the results were affected by the diversity of pathogenetic mechanisms leading to the ARDS because of various underlying disorders of the study group in the previous reports. The purpose of the present study was to evaluate the roles of TNF-$\alpha$ and IL-$1{\beta}$ as a predictable marker for development of ARDS in the patients with septic syndrome, in which the pathogenesis is believed to be mainly cytokine-mediated. Methods: Thirty-six patients of the septic syndrome hospitalized in the intensive care units of the Asan Medical Center were studied. Sixteens suffered from ARDS, whereas the remaining 20 were at the risk of developing ARDS(acute hypoxemic respiratory failure, AHRF). In all patients venous blood samples were collected in heparin-coated tubes at the time of enrollment, at 24 and 72 h thereafter. TNF-$\alpha$ and IL-$1{\beta}$ was measured by an enzyme-linked immunosorbent assay (ELISA). All data are expressed as median with interquartile range. Results: 1) Plama TNF-$\alpha$ levels: Plasma TNF-$\beta$ levels were less than 10pg/mL, which is lowest detection value of the kit used in this study within the range of the $mean{\pm}2SD$, in all of the normal controls, 8 of 16 subjects of ARDS and in 8 in 20 subjects of AHRF. Plasma TNF-$\alpha$ levels from patients with ARDS were 10.26pg/mL(median; <10-16.99pg/mL, interquartile range) and not different from those of patients at AHRF(10.82, <10-20.38pg/mL). There was also no significant difference between pre-ARDS(<10, <10-15.32pg/mL) and ARDS(<10, <10-10.22pg/mL). TNF-$\alpha$ levels were significantly greater in the patients with shock than the patients without shock(12.53pg/mL vs. <10pg/mL) (p<0.01). There was no statistical significance between survivors(<10, <10-12.92pg/mL) and nonsurvivors(11.80, <10-20.8pg/mL) (P=0.28) in the plasma TNF-$\alpha$ levels. 2) Plasma IL-$1{\beta}$ levels: Plasma IL-$1{\beta}$ levels were less than 0.3ng/mL, which is the lowest detection value of the kit used in this study, in one of each patients group. There was no significant difference in IL-$1{\beta}$ levels of the ARDS(2.22, 1.37-8.01ng/mL) and of the AHRF(2.13, 0.83-5.29ng/mL). There was also no significant difference between pre-ARDS(2.53, <0.3-8.34ngfmL) and ARDS(5.35, 0.66-11.51ng/mL), and between patients with septic shock and patients without shock (2.51, 1.28-8.34 vs 1.46, 0.15-2.13ng/mL). Plasma IL-$1{\beta}$ levels were significantly different between survivors(1.37, 0.4-2.36ng/mL) and nonsurvivors(2.84, 1.46-8.34ng/mL). Conclusion: Plasma TNF-$\alpha$ and IL-$1{\beta}$ level are not a predictable marker for development of ARDS. But TNF-$\alpha$ is a marker for shock in septic syndrome. These result could not exclude a possibility of pathophysiologic roles of TNF-$\alpha$ and IL-$1{\beta}$ in acute lung injury because these cytokine could be locally produced and exert its effects within the lungs.

• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1236-1251
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• 1998

Background : TNF-$\alpha$ appears to be a central mediator of the host response to sepsis. While TNF-$\alpha$ is mainly considered a proinflammatory cytokine, it can also act as a direct cytotoxic cytokine. However, there are not so many studies about the relationship bet ween TNF-$\alpha$ level and lung injury severity in ALI, particularly regarding the case of ALI caused by direct lung injury such as diffuse pulmonary infection. Recently, a natural defense mechanism, known as the stress response or the heat shock response, has been reported in cellular or tissue injury reaction. There are a number of reports examining the protective role of pre-induced heat stress proteins on subsequent LPS-induced TNF-$\alpha$ release from monocyte or macrophage and also on subsequent LPS-induced ALI in animals. However it is not well established whether the stress protein synthesis such as HSP can be induced from rat alveolar macrophages by in vitro or in vivo LPS stimulation. Methods : We measured the level of TNF-$\alpha$, the percentage of inflammatory cells in bronchoalveolar lavage fluid, protein synthesis in alveolar macrophages isolated from rats at 1, 2, 3, 4, 6, 12, and 24 hours after intratracheal LPS instillation. We performed histologic examination and also obtained histologic lung injury index score in lungs from other rats at 1, 2, 3, 4, 6, 12, 24 h after intratracheal LPS instillation. Isolated non-stimulated macrophages were incubated for 2 h with different concentration of LPS (0, 1, 10, 100 ng/ml, 1, or 10 ${\mu}g/ml$). Other non-stimulated macrophages were exposed at $43^{\circ}C$ for 15 min, then returned to at $37^{\circ}C$ in 5% CO2-95% for 1 hour, and then incubated for 2 h with LPS (0, 1, 10, 100ng/ml, 1, or 10 ${\mu}g/ml$). Results : TNF-$\alpha$ levels began to increase significantly at 1 h, reached a peak at 3 h (P<0.0001), began to decrease at 6 h, and returned to control level at 12 h after LPS instillation. The percentage of inflammatory cells (neutrophils and alveolar macrophages) began to change significantly at 2 h, reached a peak at 6 h, began to recover but still showed significant change at 12 h, and showed insignificant change at 24 h after LPS instillation compared with the normal control. After LPS instillation, the score of histologic lung injury index reached a maximum value at 6 h and remained steady for 24 hours. 35 kDa protein band was newly synthesized in alveolar macrophage from 1 hour on for 24 hours after LPS instillation. Inducible heat stress protein 72 was not found in any alveolar macrophages obtained from rats after LPS instillation. TNF-$\alpha$ levels in supernatants of LPS-stimulated macro phages were significantly higher than those of non-stimulated macrophages(p<0.05). Following LPS stimulation, TNF-$\alpha$ levels in supernatants were significantly lower after heat treatment than in those without heat treatment (p<0.05). The inducible heat stress protein 72 was not found at any concentrations of LPS stimulation. Whereas the 35 kDa protein band was exclusively found at dose of LPS of 10 ${\mu}g/ml$. Conclusion : TNF-$\alpha$ has a direct or indirect close relationship with lung injury severity in acute lung injury or acute respiratory distress syndrome. In vivo and in vitro LPS stimulation dose not induce heat stress protein 72 in alveolar macrophages. It is likely that 35 kDa protein, synthesized by alveolar macrophage after LPS instillation, does not have a defense role in acute lung injury.

• Pediatric Infection and Vaccine
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• v.11 no.1
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• pp.126-130
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• 2004

Neisseria meningitidis is a leading cause of meningitis and septicemia in children and young adults. Meningococcemia, the most severe form of infection, represents a part of the various spectrum of the illness, and its clinical manifestations varied from mild fever and occult bacteriemia to fulminant catastrophic events(e.g., sepsis, shock, and death) within a few hours after onset of symptoms. Complement deficiencies, either congenital or acqired, increase the risk for invasive meningococcal disease. Since C3 plays a critical role in the complement cascade, congenital C3 deficiency or conditions that decrease C3(e.g., systemic lupus erythematosus, cirrhosis, nephritis, C3 nephritic factor) increase the risk for invasive disease due to pyogenic bacteria including N. meningitidis. We had experienced a case of meningococcemia and meningococcal meningitis presenting with mild fever, petechiae, and purpura. The patient was a 7-year old male. He had mild fever, vomiting, headache, nuchal rigidity, petechiae and purpura on both lower extremities, which spreaded to the whole body. His blood culture grew Neisseria meningitidis. The diagnosis of meningococcal meningitis was confirmed by examination of cerebrospinal fluid. The clinical symptoms of the illness were improved after treatment of antibiotics(cefotaxime) for 12 days. However the patient had developed generalized edema, microscopic hematuria & proteinuria on the third day after admission. High ASO titer and low serum C3 level were also noted. The microscopic hematuria returned to normal about 2 months after discharge. The C3 level returned to normal range about 3~4 months after discharge. we report a case of combined acute poststreptococcal glomerulonephritis and acute invasive meningococcal disease with reference review.

• Journal of Aquaculture
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• v.18 no.1
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• pp.7-12
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• 2005

This study was conducted to investigate antioxidant enzyme activity (catalase and superoxide dismutase) and Heat Shock Protein 70 (HSP70) mRNA variation in hepatopancreas of abalone (Haliotis discus hannai) cultured under several acute water temperatures. Abalones were cultured at 10, 15, 20, 25 and $30^{\circ}C$, for 0, 6, 12, 24 and 48 hours, respectively. The HSP70 mRNA expression in hepatopancreas was more increased at $30^{\circ}C$ compared to those at 10. 15, 20 (control) and $25^{\circ}C$. The superoxide dismutase (SOD) activity was increased in hepato-pancreas at all water temperature conditions compared to the control ($20^{\circ}C$). The SOD activity at high water temperature (25 and $30^{\circ}C$) tended to be increased after 12 hours, and was increased immediately after exposure to low water temperature (10 and $15^{\circ}C$). and then was recovered to starting level after the increase. Also, catalase (CAT) activity in hepatopancreas was increased in all the groups except for at $10^{\circ}C$ than the control ($20^{\circ}C$). Survival rate of abalone was $100\%$ at 10, 15, 20 and $25^{\circ}C$, but $92\%$ at $30^{\circ}C$. Thus, according to our study, when abalone is appeared at $20^{\circ}C$, defense mechanism against stress at low water temperature can be accelerated to be stabilized at about $5^{\circ}C$. In the case of exposure of abalone to high water temperature, antioxidant enzyme and HSP70 expression were increased due to elevated physiological stimulation factor, such as temperature.

• Journal of the Korean Regional Science Association
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• v.32 no.1
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• pp.27-49
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• 2016

This study examines the effects of real exchange rate (RER) depreciation shocks on firm-level productivity and employment in Daegu-Gyeongbuk manufacturing industries during 2006-2012. In particular, the study focuses on a sharp and persistent RER depreciation of the Korean Won from 2007 to 2009, which is a situation akin to a natural experiment in Korea. We find that RER depreciation has positive effects on productivity for firms with high export exposure in foreign markets. However, these effects disappear when RER depreciation persists. In addition, we do not find evidence that RER depreciation affects employment of Daegu-Gyeongbuk firms significantly. Firms in Daegu-Gyeongbuk region should pursue core competency to obtain international competitiveness rather than depending on temporary better price condition driven by RER depreciation. Further, policy makers in a local government should provide firms with financial and investment support to encourage innovation and R&D.

• Journal of Yeungnam Medical Science
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• v.2 no.1
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• pp.229-235
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• 1985

This study was undertaken for the clinical evaluation and statistical analysis on the 88 women with histopathologically confirmed ectopic pregnancies who were admitted and treated from grand opening on May-28, 1983 to Sept.-30, 1985. Incidence of ectopic pregnancy was 1 in 22.2 deliveries and the most common age group was in 30~34 years of age. There was tendency of decreasing incidencies as the gravidity, panty or artificial abortion were over 3. The most common etiologic factor was pelvic inflammatory disease and procedures for family planning were the next common. Common symptoms were lower abdominal pain (85.2%) and vaginal spotting (56.8%). At the admission, hemoglobin level under 10gm% were 44.3%, 69.5% of urine HCG tests were positive. Culdocentesis was positive only in 75.9%. Termination was frequent at 6 ~ 7 weeks of gestation mostly with rupture or abortion. Free blood in the abdominal cavity was averaged 1,224 ml. 4 cases of clinicobiochemically suspected ectopic pregnancies with spontaneous regression were excluded, and there was no fatal case treated in hospital.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.2
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• pp.227-236
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• 2010

This study was carried out to investigate the anti-oxidative and anti-inflammatory actions of Hericium erinaceus mycelia in BALB/C mice injected with lopopolysaccharide (LPS), called endotoxin. Mice (6 weeks of age) weighing approximately $24.73\pm0.11$ g were divided into 5 groups and were fed on the experimental diets containing Hericium erinaceus mycelia powder (HMP) for 1 week. Experimental groups were NC (normal control), HMP-C (HMP control), LC (LPS control), HMP 3%, and HMP 10%. Endotoxin shock was induced by intraperitoneal injection of LPS (100 mg/kg BW). NC and HMP-C groups were injected with saline solution (100 mg/kg BW). Food efficiency ratio were significantly (p<0.05) decreased in the HMP supplementation groups. Total fat and $\beta$-glucan excretion were higher in HMP supplementation groups than NC and LC groups, while plasma TG level was not different among groups. Plasma ALT levels were significantly (p<0.05) lower in the HMP supplementation groups than in LC group at 8 hr after LPS injection, while tumor necrosis factor-$\alpha$ and interleukine-6 levels of plasma were not different among groups. Hepatic superoxide dismutase, glutathione-reductase (GSH-red), and glutathione-peroxidase activities were higher in the HMP supplementation groups than in LC group at 4 hr after intraperitoneal injection of LPS. Hepatic GSH levels and protein expression of GSH-red was significantly (p<0.05) higher in the HMP supplemented groups than in LC group at 1 hr, 4 hr and 8 hr after LPS injection. From the above results, it is concluded that Hericium erinaceus mycelia may ameliorate hepatic oxidative stress by LPS through the elevation of hepatic glutathione level and antioxidant enzyme activities, which support the hepatoprotective effect of Hericium erinaceus mycelia.