• Journal of Mechanical Science and Technology
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• v.17 no.10
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• pp.1496-1506
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• 2003

The SIMP (solid isotropic material with penalization) approach is perhaps the most popular density variable relaxation method in topology optimization. This method has been very successful in many applications, but the optimization solution convergence can be improved when new variables, not the direct density variables, are used as the design variables. In this work, we newly propose S-shape functions mapping the original density variables nonlinearly to new design variables. The main role of S-shape function is to push intermediate densities to either lower or upper bounds. In particular, this method works well with nonlinear mathematical programming methods. A method of feasible directions is chosen as a nonlinear mathematical programming method in order to show the effects of the S-shape scaling function on the solution convergence.

• Fibers and Polymers
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• v.3 no.2
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• pp.55-59
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• 2002

The thermal reaction of acetoacetanilide in the presence of aniline or phenol yielded carbanilide in quantitative yields. This reaction was applied to the synthesis of polyurea. Bisacetoacetamides were prepared from diamines and diketene in DMF. They were thermally polymerized in the presence of phenol or a diamine (6FDA) to yield polyureas of low molecular weights. The polymers were soluble in DMSO and NMP. $^1{H-NMR}$ analysis showed that they had amino group terminated structures. Poly(urea-imide) was synthesized by the reaction of an oligourea diamine with pyromellitic dianhydride in NMP. The concentration of terminal amino groups was determined by an acid-base titration. The thermal property of poly(urea-imide) was evaluated by thermogravimetric analysis (TGA). Initial decompisition took place at 332-$350^{\circ}C$.

• The korean journal of orthodontics
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• v.51 no.6
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• pp.407-418
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• 2021

Objective: To investigate differences in the heritability of skeletodental characteristics between twin pairs with skeletal Class I and Class II malocclusions. Methods: Forty Korean adult twin pairs were divided into Class I (C-I) group (0° ≤ angle between point A, nasion, and point B [ANB]) ≤ 4°; mean age, 40.7 years) and Class II (C-II) group (ANB > 4°; mean age, 43.0 years). Each group comprised 14 monozygotic and 6 dizygotic twin pairs. Thirty-three cephalometric variables were measured using lateral cephalograms and were categorized as the anteroposterior, vertical, dental, mandible, and cranial base characteristics. The ACE model was used to calculate heritability (A > 0.7, high heritability). Thereafter, principal component analysis (PCA) was performed. Results: Twin pairs in C-I group exhibited high heritability values in the facial anteroposterior characteristics, inclination of the maxillary and mandibular incisors, mandibular body length, and cranial base angles. Twin pairs in C-II group showed high heritability values in vertical facial height, ramus height, effective mandibular length, and cranial base length. PCA extracted eight components with 88.3% in the C-I group and seven components with 91.0% cumulative explanation in the C-II group. Conclusions: Differences in the heritability of skeletodental characteristics between twin pairs with skeletal Class I and II malocclusions might provide valuable information for growth prediction and treatment planning.

• Journal of Microbiology and Biotechnology
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• v.32 no.2
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• pp.228-237
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• 2022

In this study, the effects of the immune stimulator Euglena gracilis (Euglena) in cyclophosphamide (CCP)-induced immunocompromised mice were assessed. The key component β-1,3-glucan (paramylon) constitutes 50% of E. gracilis. Mice were orally administered Euglena powder (250 and 500 mg/kg body weight (B.W.)) or β-glucan powder (250 mg/kg B.W.) for 19 days. In a preliminary immunology experiment, ICR mice were intraperitoneally injected with 80 mg of CCP/kg B.W. during the final 3 consecutive days. In the main experiment, BALB/c mice were treated with CCP for the final 5 days. To evaluate the enhancing effects of Euglena on the immune system, mouse B.W., the spleen index, natural killer (NK) cell activity and mRNA expression in splenocytes lungs and livers were determined. To detect cytokine and receptor expression, splenocytes were treated with 5 ㎍/ml concanavalin A or 1 ㎍/ml lipopolysaccharide. The B.W. and spleen index were significantly increased and NK cell activity was slightly enhanced in all the experimental groups compared to the CCP-only group. In splenocytes, the gene expression levels of tumor necrosis factor-α, interferon-γ, interleukin (IL)-10, IL-6, and IL-12 receptor were increased in the E. gracilis and β-glucan groups compared to the CCP-only group, but there was no significant difference. Treatment with 500 mg of Euglena/kg B.W. significantly upregulated dectin-1 mRNA expression in the lung and liver compared to the CCP-only group. These results suggest that Euglena may enhance the immune system by strengthening innate immunity through immunosuppression.

• Journal of Microbiology and Biotechnology
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• v.34 no.6
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• pp.1299-1306
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• 2024

Antibiotics are used to control infectious diseases. However, adverse effects of antibiotics, such as devastation of the gut microbiota and enhancement of the inflammatory response, have been reported. Health benefits of fermented milk are established and can be enhanced by the addition of probiotic strains. In this study, we evaluated effects of fermented milk containing Lacticaseibacillus rhamnosus (L. rhamnosus) SNUG50430 in a mouse model with antibiotic treatment. Fermented milk containing 2 × 10⁵ colony-forming units of L. rhamnosus SNUG50430 was administered to six week-old female BALB/c mice for 1 week. Interleukin (IL)-10 levels in colon samples were significantly increased (P < 0.05) compared to water-treated mice, whereas interferon-gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) were decreased, of mice treated with fermented milk containing L. rhamnosus SNUG50430-antibiotics-treated (FM+LR+Abx-treated) mice. Phylum Firmicutes composition in the gut was restored and the relative abundances of several bacteria, including the genera Coprococcus and Lactobacillus, were increased in FM+LR+Abx-treated mice compared to PBS+Abx-treated mice. Interestingly, abundances of genus Coprococcus and Lactobacillus were positively correlated with IL-5 and IL-10 levels (P < 0.05) in colon samples and negative correlated with IFN-γ and TNF-α levels in serum samples (P < 0.001). Acetate and butyrate were increased in mice with fermented milk and fecal microbiota of FM+LR+Abx-treated mice were highly enriched with butyrate metabolism pathway compared to water-treated mice (P < 0.05). Thus, fermented milk containing L. rhamnosus SNUG50430 was shown to ameliorate adverse health effects caused by antibiotics through modulating immune responses and the gut microbiota.

• Tuberculosis and Respiratory Diseases
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• v.70 no.3
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• pp.199-205
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• 2011

Social welfare services for respiratory-disabled persons in Korea are offered based on the respiratory impairment grade, which is determined by 3 clinical parameters; dyspnea, forced expiratory volume in 1 second ($FEV_1$), and arterial oxygen tension. This grading system has several limitations in the objective assessment of respiratory impairment. We reviewed several guidelines for the evaluation of respiratory impairment and relevant articles. Then, we discussed a new grading system with respiratory physicians. Both researchers and respiratory physicians agreed that pulmonary function tests are essential in assessing the severity of respiratory impairment, forced vital capacity (FVC), $FEV_1$ and single breath diffusing capacity ($DL_{co}$) are the primarily recommended tests. In addition, we agreed that arterial blood gas analysis should be reserved for selected patients. In conclusion, we propose a new respiratory impairment grading system utilizing a combination FVC, $FEV_1$ and $DL_{co}$ scores, with more social discussion included.

• Molecules and Cells
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• v.40 no.11
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• pp.855-863
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• 2017

Adipose tissue plays a central role in regulating dynamic cross-talk between tissues and organs. A detailed description of molecules that are differentially expressed upon changes in adipose tissue mass is expected to increase our understanding of the molecular mechanisms that underlie obesity and related metabolic co-morbidities. Our previous studies suggest a possible link between endophilins (SH3Grb2 proteins) and changes in body weight. To explore this further, we sought to assess the distribution of endophilin A2 (EA2) in human adipose tissue and experimental animals. Human paired adipose tissue samples (subcutaneous and visceral) were collected from subjects undergoing elective abdominal surgery and abdominal liposuction. We observed elevated EA2 gene expression in the subcutaneous compared to that in the visceral human adipose tissue. EA2 gene expression negatively correlated with adiponectin and chemerin in visceral adipose tissue, and positively correlated with $TNF-{\alpha}$ in subcutaneous adipose tissue. EA2 gene expression was significantly downregulated during differentiation of preadipocytes in vitro. In conclusion, this study provides a description of EA2 distribution and emphasizes a need to study the roles of this protein during the progression of obesity.

• Parasites, Hosts and Diseases
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• v.51 no.3
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• pp.383-385
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• 2013

Uzbekistan is endemic of cystic echinococcosis (CE). In order to estimate endemicity of CE, we collected data from emergency surgery due to CE in 2002-2010 and also investigated the prevalence of hydatid cysts in the liver and lungs of sheep at an abattoir in Uzbekistan from July 2009 to June 2010. In 14 emergency hospitals, 8,014 patients received surgical removal or drainage of CE during 2002-2010, and 2,966 patients were found in 2010. A total of 22,959 sheep were grossly examined of their liver and lungs, and 479 (2.1%) and 340 (1.5%) of them were positive for the cyst in the liver and lungs, respectively. Echinococcus granulosus is actively transmitted both to humans and sheep, and CE is a zoonotic disease of public health priority in Uzbekistan.

• Journal of Korean Society of Rural Planning
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• v.22 no.4
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• pp.1-11
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• 2016

Public transportation is public service that is contributed to the convenience of the public. However, opportunity for public services in rural areas is weaker than the chance in urban areas. The purpose of this study is to evaluate accessibility of various public facilities using public transportation. To evaluate the accessibility, we calculate the various time from community center to the nearest bus stop, walking time, riding time in bus, and waiting time for transfer. The results of this study ares as follows; (1) Villages occupy 19.8% in rural areas that walking time from community center to the nearest bus stop takes over 10 minutes in integrated Chungju-si; (2) The average speed is 21.9 km/hr estimated to departure and arrival time of bus route; (3) The accessibility time from community center using the average bus speed takes 15.43 minutes to public facilities, 35.15 minutes to emergency center, 8.70 minutes to medical center, 9.70 minutes to elementary school, 16.26 minutes to middle school, and 22.61 minutes high school; (4) The transfer time of public transportation takes 13.46, 21.96, 10.48, 7.78, 11.11, 16.10 minutes to public facilities, emergency center, medical center, elementary school, middle school, and high school, respectively; (4) Traffic accessibility using bus vehicles in the East and South Chungju-si is lower than areas in the West and North Chungju-si. Some villages surrounding public offices (eup-myeon office) which have a high density of population, indicate a high traffic accessibility.

• Obstetrics & gynecology science
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• v.61 no.6
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• pp.662-668
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• 2018

Objective This study was to identify the risk factors for cytological progression in women with atypical squamous cells of undetermined significance (ASC-US) or low-grade squamous intraepithelial lesions (LSIL). Methods We analyzed data from women infected with the human papillomavirus (HPV) who participated in the Korean HPV cohort study. The cohort recruited women aged 20-60 years with abnormal cervical cytology (ASC-US or LSIL) from April 2010. All women were followed-up at every 6-month intervals with cervical cytology and HPV DNA testing. Results Of the 1,158 women included, 654 (56.5%) and 504 (43.5%) women showed ASC-US and LSIL, respectively. At the time of enrollment, 143 women tested positive for HPV 16 (85 single and 58 multiple infections). Cervical cytology performed in the HPV 16-positive women showed progression in 27%, no change in 23%, and regression in 50% of the women at the six-month follow-up. The progression rate associated with HPV 16 infection was higher than that with infection caused by other HPV types (relative risk [RR], 1.75; 95% confidence interval [CI], 1.08-2.84; P=0.028). The cytological progression rate in women with persistent HPV 16 infection was higher than that in women with incidental or cleared infections (P<0.001). Logistic regression analysis showed a significant relationship between cigarette smoking and cytological progression (RR, 4.15; 95% CI, 1.01-17.00). Conclusion The cytological progression rate in HPV 16-positive women with ASC-US or LSIL is higher than that in women infected with other HPV types. Additionally, cigarette smoking may play a role in cytological progression.