• The korean journal of orthodontics
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• v.47 no.1
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• pp.39-49
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• 2017

Objective: This retrospective, cross-sectional study aimed to establish reference data for normal crown and root lengths and the root-crown ratios (R/C ratios) for the mature maxillary and mandibular incisors in a Korean population by using cone-beam computed tomography (CBCT). Methods: We included 672 Korean patients (141 men and 531 women; mean age, $27.2{\pm}7.7years$) who underwent CBCT examinations during various dental treatments. Crown and root lengths and the R/C ratios of the maxillary and mandibular incisors were measured using CBCT data, which were analyzed to detect significant differences between demographic factors as well as sagittal and vertical skeletal or occlusal relationships. Results: Teeth of the same type in each half-arch were symmetrical. The mean R/C ratios varied from 1.1 to 1.2 for the maxillary incisors and from 1.3 to 1.4 for the mandibular incisors. Crown and root lengths were greater in men than in women, regardless of tooth type. Root lengths and R/C ratios for the mandibular incisors were significantly greater in patients with skeletal Class II malocclusion or an excessive overjet than in the other patients. The R/C ratios for the mandibular incisors were lower in patients with an open bite than in those with a normal or deep bite. Moreover, the R/C ratios for the mandibular incisors increased with age. Conclusions: The data obtained in our study can serve as reference values for crown and root lengths and the R/C ratios for the maxillary and mandibular incisors in the Korean population.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5037-5042
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• 2012

Background: Tobacco contains agents which generate various potent DNA adducts that can cause gene mutations. Production of DNA adducts may be neutralized by glutathione S transferase (GST) along with other phase I and phase II enzyme systems. The existence of null type of GST among the population increases the susceptibility to various disorders and diseases. The present study focuses on the impact of high tobacco usage and possible null type mutation in GST loci. Methods: Genotypes of GST were detected by multiplex polymerase chain reaction in unrelated 504 volunteers of high tobacco using natives of Gujarat. Allelic frequencies were calculated using Statistical Package for Social Studies-16 software. Hardy Weinberg Equilibrium (HWE) was calculated using Chi square test. Two sided Fisher's significance test was used to compare allelic frequencies of different populations. Results: The frequency of homozygous null genotype of GSTM1 and GSTT1 were 20% (95% CI 16.7-23.9) and 35.5% (95% CI 31.4-39.9) respectively. The GSTM1 and GSTT1 null allele frequency distribution in the Gujarat population was significantly deviating from HWE. GSTT1 null frequency of Gujaratians was significantly higher and different to all reported low tobacco using Indian ethnics, while GSTM1 was not differing significantly. Conclusion: Tobacco usage significantly influences the rate of mutation and frequency of GSTT1 and M1 null types among the habituates. The rate of mutation in GSTT1 loci was an undeviating response to the dose of tobacco usage among the population. This mutational impact of tobacco on GSTT1 postulates the possible gene - environment interaction and selection of null genotype among the subjects to prone them under susceptible status for various cancers and even worst to cure the population with GSTT1 dependent drugs.

• Clinical and Experimental Reproductive Medicine
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• v.13 no.2
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• pp.175-180
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• 1986

It has been reported that oral kallikrein therapy exerts a favourable effect on sperm motility in asthenozoospermic patients. In order to evaluate the efficacy of kallikrein on asthenozoospermia, a total of 20 subfertile male patients with varicocele, whose sperm counts were less than $40{\times}10^6/ml$ and sperm motility was less than 30%, was subjected to this clinical study (Table 1). They were divided into 2 study groups: 1) Varicocelectomy group consisted of 10 patients with varicocele (grade II-III) who underwent varicocelectomy. 2) Kallikrein group was composed of 10 patients with varicocele (grade I) who were given kallikrein orally 600 KU (kallikrein unit) daily divided 3 times after meal for 3 to 9 months. Semen analyses were repeated twice before the study, once a month during the study and twice after the study. Effective results designate that sperm parameters improved more than 30% from the basical levels after varicocelectomy or kallikrein exposure. Sperm counts increased from $32.5{\times}10^5/ml$ to $45.5{\times}10^6/ml$ after varicocelectomy in 3 patients and sperm motility increased from 25% to 38.5% after varicocelectomy in 3 patients. Pregnancy occurred in 2 patients of 3 responders and 1 patient of 7 non-responders 3 to 6 months after varicocelectomy in Varicocelectomy group. Sperm motility increased from 28% to 40.2% after kallikrein treatment in 3 patients. Pregnancy occurred in 2 patients of the 3 responders in Kallikrein group (Tables 2-3). There were no significant changes in volume and morphology in Varicocelectomy group before after varicocelectomy and no significant changes in volume, counts, and morphology before and after kallikrein exposure. No remarkable side effects were noted with kallikrein treatment.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.5
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• pp.557-564
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• 2005

The objective of this study is to evaluate a criteria of intercepting capacity and a reduction goal of overflow pollution load in combined sewer system. In the current criteria of intercepting capacity in the domestic sewage facility standard, it is known that three times of peak sewage (Q) in dry period or runoff flow by 2mm/hr is not appropriate since the intercepted flow is estimated by runoff and show different result even in the same watershed. Though a reduction goal of overflow pollution load can be determined from 1) same level of storm-water runoff pollution load in separated storm sewer, 2) less than 5% sewage load in dry weather period, by the domestic sewage facility standard, the simulated results from storm-water model show large differences between two criteria. While it is predicted that sewage pollution load standard three time larger than separated storm sewer standard in high population density and urbanized area, it is shown that separate storm sewer standard larger than sewage pollution load standard in middle population density and developing area. Accordingly, it is proposed that more reasonable intercepting flow and reduction goal of overflows pollution load should be established to minimize discharging pollution load in combined sewer systems. For the purpose, a resonable standard has to be amended by pollution load balance considering the characteristics of a watershed for generation, collection, treatment, and discharging flow.

• Journal of the Korean association of regional geographers
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• v.16 no.2
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• pp.123-136
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• 2010

To grasp the migration characteristics in the Busan Metropolitan Area (BMA), this study analyzed household characteristics and migration selectivity. The major findings of the study are as follows: first, young (especially 25 to 34 years of age) and single person households have greater propensity to migrate out from BMA, and their home ownership rate is low. These trends are much stronger in households that migrate out towards the Seoul Metropolitan Area from Busan. Second, age and educational selectivity of migration is evident. The characteristics of movers are quite different from those of stayers at Busan. Young people are more likely to migrate out of Busan, and higher levels of education are deeply associated with higher mobility. Through analyzing four high schools in Busan, it is acknowledged that most honor students entered 4-year universities in Seoul. The outflow of highly educated young people may induce the brain drain. Busan is undergoing both population decline and the problems caused by the brain drain.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.2141-2146
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• 2013

Cervical cancer is the third most common form of cancer that strikes Malaysian women. The National Cancer Registry in 2006 and 2007 reported that the age standardized incidence (ASR) of cervical cancer was 12.2 and 7.8 per 100,000 women, respectively. The cumulative risk of developing cervical cancer for a Malaysian woman is 0.9 for 74 years. Among all ethnic groups, the Chinese experienced the highest incidence rate in 2006, followed by Indians and Malays. The percentage cervical cancer detected at stage I and II was 55% (stage I: 21.0%, stage II: 34.0%, stage III: 26.0% and stage IV: 19.0%). Data from Ministry of Health Malaysia (2006) showed a 58.9% estimated coverage of pap smear screening conducted among those aged 30-49 years. Only a small percentage of women aged 50-59 and 50-65 years old were screened, 14% and 13.8% coverage, respectively. Incidence of cervical cancer was highest (71.6%) among those in the 60-65 age group (MOH, 2003). Currently, there is no organized population-based screening program available for the whole of Malaysia. A pilot project was initiated in 2006, to move from opportunistic cervical screening of women who attend antenatal and postnatal visits to a population based approach to be able to monitor the women through the screening pathway and encourage women at highest risk to be screened. The project was modelled on the screening program in Australia with some modifications to suit the Malaysian setting. Substantial challenges have been identified, particularly in relation to information systems for call and recall of women, as well as laboratory reporting and quality assurance. A cost-effective locally-specific approach to organized screening, that will provide the infrastructure for increasing participation in the cervical cancer screening program, is urgently required.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.67.2-67.2
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• 2014

The presence of multiple populations is now well-established in most globular clusters in the Milky Way. In light of this progress, here we suggest a new model explaining the origin of the Sandage period-shift and the difference in mean period of type ab RR Lyrae variables between the two Oosterhoff groups. In our models, the instability strip in the metal-poor group II clusters, such as M15, is populated by second generation stars (G2) with enhanced helium and CNO abundances, while the RR Lyraes in the relatively metal-rich group I clusters like M3 are mostly produced by first generation stars (G1) without these enhancements. This population shift within the instability strip with metallicity can create the observed period-shift between the two groups, since both helium and CNO abundances play a role in increasing the period of RR Lyrae variables. The presence of more metal-rich clusters having Oosterhoff-intermediate characteristics, such as NGC 1851, as well as of most metal-rich clusters having RR Lyraes with longest periods (group III) can also be reproduced, as more helium-rich third and later generations of stars (G3) penetrate into the instability strip with further increase in metallicity. Therefore, although there are systems where the suggested population shift cannot be a viable explanation, for the most general cases, our models predict that the RR Lyraes are produced mostly by G1, G2, and G3, respectively, for the Oosterhoff groups I, II, and III.

• Land and Housing Review
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• v.10 no.2
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• pp.29-43
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• 2019

Colombia experiences a population growth in their metropolitan areas through an accelerated urbanization process, a housing deficit and a shortage of urban developable land. To solve these problems, the central government developed a national policy for a large-scale housing city development including supra-municipalities planning instruments such as Macroprojects. However, the amount of housing land supplied by this policy is insufficient and additional policies for shortage housing and qualitative deficit are required, particularly in regions with a high concentration of population. The purpose of the study is to compare urban development systems of Colombia and Korea and explore the possibility of applying guidelines to Colombia through i) comparing the capital region cities of the two countries with an asymmetry context method, ii) comparing both urban planning system founding similarities and differences, and iii) suggesting new urban development challenges in the Bogotá metropolitan area based on Korea's new town experience.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.613-619
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• 1994

To investigate the population differences of small yellow croaker (Pseudosciaena polyactis BLEEKER) in the Yellow Sea, five catching sites (three from China; Zoushan, Shanghai and Qingdao, two from Korea; Inchon and Mokpo) were selected for sampling. The populations of small yellow croaker from all five catching sites were investigated to analyze their mtDNA's restriction fragment length polymorphism (RFLP) using 18 kinds of restriction enzymes. The average molecular size of the entire mtDNA was estimated at $16.9{\pm}0.6\;kb$. According to the results of RFLP analysis, a total of 40 restriction sites were identified in every population surveyed and the overall cleavage patterns of mtDNA, based on the RFLP, showed similar tendencies. However, the five restriction enzymes such as ApaI, EcoRI, PstI, SmaI and SstII showed slightly different cleavage patterns which could have resulted from individual variations between the populations of Korea and China.

• Korean Journal of Veterinary Service
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• v.25 no.1
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• pp.1-7
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• 2002

Recently, the rabies cases have been reported in Paju- and Yangju-gun, Gyeonggj province near Seoul metropolitan area. The Pukhansan national park, nearly located from the cities, is suspected to be a high risk area for incidence and spread of the rabies to metropolitan area. This study was conducted to investigate the prevalence rate for rabies antibody of dogs near the Pukhansan national park and in some other districts in Seoul metropolitan city. From march to october 2001, a total of 306 serum samples were taken from dogs for breeding(189) md pet dogs(117) in 4 districts near the Pukhansan national park and other districts of Seoul. Rabies virus antibodies in sera were detected by neutralizing peroxidase - linked as say (NPLA). Of the 306 sera of dogs tested, 74 (24.2%) were positive to rabies virus antibody. The prevalence rates of rabies antibody in Pukhansan national park area and in the other districts of Seoul city were 23.7% and 25.3%, respectively There was no significant difference in the prevalence rate between these two districts. The prevalence rates of rabies antibody in pet dogs and dogs for breeding were 40.2% and 14.3% respectively. The prevalence rates of rabies antibodies in less than 1 year, 1∼<2 years, 2∼<3 years, and over 3 years old dogs were 14.5%, 22.4%, 32.6%, and 27.1%, respectively, and overall 24.2% in the dog population. In addition, we found that dogs less than 1 year old had lower antibody prevalence than those over 1 year old. It was concluded that enhancement of vaccination is important in the prevention of the rabies, and that rabies vaccines should not be less supplied than the population of the dog.