• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.147-153
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• 2000

This study was conducted to compare probiotic activities and physiological functions of Bifidobacterium longum Mk-G7 with weveral commercial and type strains of bifidobacteria. bif. longum MK-G7 showed the highest acid tolerance against HCl and acetic acid, whereas bif. infantis Y-1 showed the lowest acid tolerance and more than 4 log cycles of viable cell count decreased due to acid injuty. Viable cell counts of bifidobacteria strains decreased more than 1.5 log cycles owing to oxygen toxicity, with the exception of Bif. longum MK-G7, Bif. infantis Y-2, Bif. longum Y-3, Bif. longum Y-6, and Bif. longum RD-13 showed the highest bile tolerance, whereas Bif. longum MK-G7 showed a medium level of bile tolerance. Only Bif. longum MK-G7 howed much higher antibiotic resistance against both tetracycline and penicillin-G in the MIC(minimum inhibitory concentration) level of 24.8 mg/I and 0.52mg/I, respectively. Bif longum Y-6, and Bif. bifidum ATCC 29539 showed more than 80% of anti-mutagenicity against NQO(4-nitroquinolinel-oxide). Since the production of cytokines such as $TNF(tumor necrosis factor)-{\alpha}$ and IL (interleukin)-6, and NO(nitric oxide) in the macrophage cell line Raw 264.7 cells increased as Bif. longum MK-G7 cell concentration increased, ti was suggested that Bif. longum MK-G7 is able to enhance immunopotentiating activity in vitro. When freeze-dred Bif. longum MK-G7 was administered to mice at the dose of 1,2,4, and 6 g/kg of body weight, all of the mice survived in all feeding groups, proving the GRAS(generally recognized as safe) status of Bif. longum MK-G7. When fermented milk containing Bif. longum MK-G7 was administered to human volunteers, viable cell count of total bifidobacteria and anaerobes in the feces increased up to 0.5 log cycles more than before the administration. In particular, Bif. logum MK-G7 ingibited the growth of Bacteroides at the level of 1.0-1.5 log cycles.

• Journal of the Korean Society of Hazard Mitigation
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• v.4 no.1 s.12
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• pp.15-24
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• 2004

Generally, a ${\pi}$-type girder composed of two I-type girders is known to have a significant disadvantage in wind resistance design because of aerodynamic instability. A representative bridge for this girder was Tacoma Narrows Bridge. Since Tacoma Narrows Bridge had very low stiffness of the bridge structure and its cross-section shape had aerodynamic instability, the bridge collapsed after severe torsion and vibration events in 19m/s wind speed. Aerodynamic vibration can be avoided by enhancing structural stiffness and damping factor and conducting a study of cross-section shapes. This study shows the angle of attack for the four-span cable stayed bridge having ${\pi}$-type cross-section and describes the aerodynamic characteristics of the changed cross-section with aerodynamic vibration damping additions, by carrying out two-dimension vibration tests. As a result of uniform flow and turbulent flow, the study shows that because the basic ${\pi}$-type cross-section alone can have efficient wind resistant stability, there is no need to have additional aerodynamic damping equipment. Since this four 230m-main-span bridge has a large frequency and also has a big stiffness compared to other bridges containing a similar cross-section, it has aerodynamic stability under the design wind speed.

• Korean Journal of Materials Research
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• v.2 no.3
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• pp.228-238
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• 1992

An investigation on the step-coverage of PECVD and $O_3$ ThCVD oxides was undertaken to implement into the void-free inter metal dielectric planarization using multi-chamber system for the submicron double level metallization. At various initial aspect ratios the instantaneous aspect ratios were measured through modelling and experiment by depositing the oxides up to $0.9{\mu}m$ in thickness in order to monitor the onset of void formation. The modelling was found to be in a good agreement with the observed instantaneous aspect ratio of TEOS-based PECVD oxide whose re-entrant angle was less than $5^{\circ}$. It is demonstrated that either keeping the instantaneous aspect ratio of PECVD oxide as a first layer less than a factor of 0.8 or employing Ar sputter etch to create sloped oxide edge ensures the void-free planarization after$O_3$ ThCVD oxide deposition whose step-coverage is superior to PECVD oxide. It has been observed that $O_3$ ThCVD oxide etchback scheme has shown higher yield of via contact chain than non etchback process, with resistance per via contact of $0.1~0.3{\Omega}/{\mu}m^2$.

• Journal of Digital Convergence
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• v.15 no.6
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• pp.439-445
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• 2017

Summary. Most of American pop music, which are dominating the hegemony of the global pop music market, have been derived from the culture of African Americans, most of whom were slaves of European immigrants. The music of black slaves must be the one of the greatest undisputed achievements that have most influenced the American history. Indeed, All of the mainstream pop music works around the world, including those in America, are the descendants of the black music with the gene of the black people. We can say, therefore, the music born through the Afro-American culture has become the music that every person around the world enjoys in the present. Accordingly, K-Pop music culture, centered in idol group, is also based on the black music. This fact suggests that the K-Pop culture can be spread into people in different customs or traditions with little resistance. The success factor of Motown, at the very center of the black music, which integrated the whole global music, is not only their incredibly outstanding music works, but also the self-consciousness the musicians have that they are strongly reluctant to settle down to present reality. This shall lead to the necessity of self-reflection for the Korean music market, which are obsessed with present popularity and only taking advantage of teenager market, and for those engaged in music business in Korea, who are lack of the artistic value and the consciousness as artist.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.2
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• pp.217-225
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• 2010

Most of the steel bridges in Korea are being currently designed by the allowable stress design method that uses the conventional deterministic factors of safety. However the limit state design based on the concept of probability, statistics and reliability engineering is becoming very popular as a global standard deign method, leading the rational and economic bridge design. As part of the fundamental research to establish the load and resistance factor design(LRFD) of steel bridges considering domestic environmental conditions and regional characteristics, an experimental design is conducted by applying AASHTO-LRFD specification especially to a steel closed-box girder, which occupies relatively a large portion of steel bridges in Korea. Throughout the experimental design according to various sectional changes, some of the issues to be considered in the LRFD design of a composite steel closed-box girder bridge are examined. In this process, an Excel-based design verification program is developed for easy computation and prevention of errors. Quantitative reliability levels of the bridge sections designed by LRFD are also estimated using a reliability analysis method, and compared with the target reliability indexes applied in the LRFD design to verify the validity of the procedure and methodology used in this study.

• Tuberculosis and Respiratory Diseases
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• v.59 no.6
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• pp.600-605
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• 2005

Background : Primary multidrug-resistant tuberculosis is defined as Mycobacterium tuberculosis isolates that are resistant to at least isoniazid and rifampin in never-been-treated tuberculosis patients, and this malady is caused by the transmission of a resistant strain from one patient, who is infected with a resistant Mycobacterium tuberculosis strain, to another patient. The prevalence of primary multidrug-resistant tuberculosis could be a good indicator of the performance of tuberculosis control programs in recent years. We conducted a case-control study to identify the risk factors for primary multidrug-resistant tuberculosis. Methods : From January 1, 2001 to, June 30, 2003, by conducting prospective laboratory-based surveillance, we identified 29 hospitalized patients with P-MDRTB and these patients constituted a case group in this study. The controls were represented by all the patients with culture-confirmed drug susceptible tuberculosis who were admitted to National Masan Hospital during the same study period. The odds ratios for the patients with primary multidrug-resistant tuberculosis, as compared with those of the patients with drug susceptible tuberculosis, were calculated for each categorical variable with 95% confidence intervals. Results : Multivariate logistic regression showed that the presence of diabetes mellitus (odds ratio 2.68; 95% confidence interval, 1.05-6.86) was independently associated with having primary multidrug-resistant tuberculosis. Conclusion : This study has shown that diabetes mellitus might be one of the risk factors for primary multidrug-resistant tuberculosis.

• Research in Community and Public Health Nursing
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• v.9 no.1
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• pp.40-63
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• 1998

A long life is the desire of many people. The purpose of this study was to describe long life factors for people aged one hundred and above on Chju island. The research was conducted using a phenomenological method to add understanding to this subject. The field work for this study was done from July, 1997 to February, 1998 on Cheju island. The sample consisted of 10 persons of one hundred or above and 12 families. They were audio-recorded and analyzed using Colaizzi's (1978) method. The results of the present study shows the following: The thoughts of the persons one hundred and above showed ten important concepts; 'dietary regimen', 'mental regimen', 'sleep regimen', 'residence regimen', 'health regimen', 'labor regimen', 'exercise regimen', 'being born', 'filial piety and posterity', 'attachment to life'. Concerning 'Dietary Regimen': Dietary regulation, Preferential food intake, Living on vegetables, Light eating, and concern for longevity in food intake were important. Concerning 'Mental Regimen' : Harmony, Clearheadedness, Mildness, Abstinence, Generosity, Relaxation, Gaiety, Inspiration and Strength were important. Concerning 'Sleep Regimen'; Enough sleeping hours, Sound sleep, Curved sleeping posture, and Comfortable bedding were important. Concerning 'Residence Regimen' ; Clean dwelling, Pleasant surroundings, Thatched house life, Living in the village with good-hearted people, and Regular life were important. Concerning 'Health Regimen'; Temperance of drug, use Proper temperature, Proper humidity, and a Clean body were important. Concerning 'Labor Regimen'; Agricultural labor, Diligence, and Domestic labor were important. Concerning Exercise Regimen': Proper exercise, and Sunbathing were important. Concerning 'Being Born' ; Strong physical constitution, Longevity lineage, and Destiny were important. Concerning 'Filial Piety and Posterity' : Showing respect to a long-lived elder and Reducing anxiety were important. Concerning 'Attachment to Life' ; The desire to live long was important. The following conclusion was made from the above results. Human beings cannot avoid death, but the span of life can be prolonged to the maximum span of human life by wisdom, health care, and proper environmental conditions. As a result, a health regimen must be imposed for longevity such as controling food intake, having positive thoughts, being relaxed, sleeping enough, clean dwelling, taking care of oneself which can improve immunity and resistance to decrease, as well as proper labor and exercise. In addition, when filial piety is served, the desire of longevity and retaining one's youthfulness for a long time can be achieved. These should be done to live long and lead a qualitative life. By the results of this research, the following is suggesed for nursing. To satisfy the basic nursing principle that nursing must be practiced to help people live long, education must be spread to people who are nursed and their family so that they can lead a healthy life. And in nursing elders, nurses must recognize that elders have a strong desire for life, even though they may have negative thoughts about life at times. Therefore nurses have to respect the elders' value of life, and help them improve their self-esteem and self -fulfilment.

• IMMUNE NETWORK
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• v.2 no.4
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• pp.242-247
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• 2002

Background: Tumor necrosis factor-alpha (TNF-$\alpha$) is known to play an important role in various conditions such as inflammation, autoimmunity, apoptosis, insulin resistance and sleep induction. Five single nucleotide polymorphisms (SNPs) have been known to affect the transcriptional activities of TNF-$\alpha$: -1,031T/C, -863C/A, -857C/T, -308G/A and -238G/A. Methods: We have investigated 5 SNPs of the promoter region of TNF-$\alpha$ gene, the distribution of 5-locus TNF-$\alpha$ haplotypes, and their haplotypic associations with previously typed HLA-A, -B and -DRB1 loci in 107 healthy unrelated Koreans. TNF-$\alpha$ SNPs were typed using PCR-single-strand conformation polymorphism (SSCP) and PCR-restriction fragment length polymorphism (RFLP) methods. Results: The allele frequencies of -1,031C, -863A, -857T, -308A, and-238A, which are known as the high-producer-type, were 19.3%, 15.9%, 14.0%, 5.9%, and 2.9%, respectively. The frequency of -308A allele, known to be associated with autoimmune diseases, was 5.9% in Koreans which was lower than Caucasians (14~17%) and somewhat higher than Japanese (1.7%). Five most common TNF-$\alpha$ haplotypes (-1,031/-863/-857/-308/-238) comprised over 95% of total haplotypes: TCCGG (58.4%), CACGG (14.8%), TCTGG (13.7%), TCCAG (5.3%), and CCCGA (3.1%). Strong positive associations (P<0.001) were observed between TCCGG and B62; between CACGG and B51, $DRB1^*0901$; between TCTGG and B35, B54, B59, $DRB1^*1201$; and between TCCAG and A33, B58, $DRB1^*0301$, $DRB1^*1302$. Five most common extended haplotypes (>3%) comprised around 16% of total haplotypes: A33-B58-TCCAG-$DRB1^*1302$, A24-B52-TCCGG-$DRB1^*1502$, A33-B44-TCCGG-$DRB1^*1302$, A24-B7-TCCGG-$DRB1^*0101$, and A11-B62-TCCGG-$DRB1^*0406$. The distribution of extended HLA and TNF-$\alpha$ haplotypes showed that most of HLA haplotypes were almost exclusively associated with particular TNF-$\alpha$ haplotypes. Conclusion: The results obtained in this study would be useful as basic data for anthropologic studies and disease association studies in Koreans.

• Korean Chemical Engineering Research
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• v.49 no.2
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• pp.175-180
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• 2011

In this study, the $TiO_{2}/V_{2}O_{5}$ hybrid semiconductors were prepared by mixing $TiO_{2}$ and $V_{2}O_{5}$, and a subsequent smash process to reduce the recombination of electron and improve the efficiency of solar cells. Dye-sensitized solar cells were constructed using the resultant hybrid semiconductor, and their electrochemical properties were also investigated. The photocurrent-voltage curve obtained with the cells indicated a significant increase in the efficiency from 2.9 to 5.7% by the factor of 2 compared to the result obtained only with $TiO_{2}$. It is believed that the introduction of $V_{2}O_{5}$ effectively transport electrons in the $TiO_{2}$ conduction band to FTO glass and suppress recombination with the dye and/or the electrolyte, thus yielding an efficient performance of the dye sensitized solar cell. The impedance values also indicated a decrease of resistance in the interface of $TiO_{2}$/dye/electrolyte supporting the constructive contributions of the smashed $TiO_{2}/V_{2}O_{5}$ hybrid semiconductors for the efficiency.

• Journal of the Korea Concrete Institute
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• v.25 no.1
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• pp.115-123
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• 2013

The steel industry, a representative industry that significantly consumes raw materials and energy, produces steel as well as a large amount of by-product steel slag through the production process. The vast habitat foundation of marine life has been destroyed due to recent reckless marine development and environment pollution, resulting in intensification of the decline of marine resources, and a solution to this issue is imperative. In order to propose a method to recycle large amounts of by-product slag into a material that can serve as an alternative to natural aggregate, the engineering properties and applicability for each mixing factor of environment friendly porous concrete as a material for the composition of marine ranches were evaluated in this study. The test results for percentage of voids per mixing ratio revealed that the margin of error for all conditions was within 2.5%. The compressive strength test results showed that the most outstanding environmental friendly porous concrete can be manufactured when mixing 30% slag aggregate and 10% specially treated granular fertilizer for the optimum volume fraction. As concrete for marine applications, the best seawater resistance was obtained with mixing conditions for high compression strength. An assessment of the ability to provide a marine life habitat foundation of environmentally friendly porous concrete showed that a greater percentage of voids facilitated implantation and inhabitation of marine life, and the mixing of specially treated granular fertilizer led to active initial implantation and activation of inhabitation. The evaluation of harmfulness to marine life depending on the mixture of slag aggregate and specially treated granular fertilizer revealed that the stability of fish is secured.