• Journal of Soil and Groundwater Environment
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• v.22 no.3
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• pp.10-17
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• 2017

In this study, the evolution and origin of major dissolved constituents of crystalline bedrock groundwater in a coastal area were evaluated using multivariate statistical and groundwater quality analyses. The groundwater types mostly belonged to the $Na(Ca)-HCO_3$ and $Ca-HCO_3$ types, indicating the effect of cation exchange. Stable isotopes of water showed two areas divided by first and secondary evaporative effects, indicating a pattern of rapid hydrological cycling. Saturation indices of minerals showed undersaturation states. Thus, the degree of evolution of groundwater is suggested as in the low to intermediate stage, based on field and laboratory analytical conditions. According to the principal component analysis (PCA) results, the chemical components of EC, $Ca^{2+}$, $Mg^{2+}$, $K^+$, $HCO_3{^-}$, $SO{_4}^{2-}$ (PCA 1), $F^-$ (PCA 3), $SiO_2$ (PCA 4), and $Fe^{2+}$ (PCA 5) are derived from various water-rock interactions. However, $NO_3{^-}$, $Na^+$, and $Cl^-$ (PCA 2) represented the chemical characteristics of both anthropogenic sources and natural sea spray.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.1
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• pp.56-64
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• 2012

Polychaete community structure and its spatial distribution was investigated in 2008 from inshore and offshore of Lake Shihwa, Korea, in order to evaluate status of the benthic environment according to construction of the dike and the water gate. In the present study, the number of species, density, and diversity of polychaete community in inshore was significantly different from those in offshore. The density of polychaete community in offshore increased with the number of species whereas the diversity in inshore increased with the number of species. Dominant species in offshore were 13 species, higher than 1% of the total polychaete individuals. Heteromastus filiformis, known as the most dominant species before the construction of the dike, was the most dominant species in offshore, which collectively account for 54% of the total polychaete individuals. In inshore, the seven species were dominant, higher than 1% of the total individuals. Lumbrineris longifolia, Polydora sp., Capitella capitata, Pseudopolydora paucibranchiata, known as pollution tolerant species, contributed to higher than 75% of the total individuals in inshore. Multivariate statistical analyses, non-metric multidimensional scaling, showed apparent difference in polychaete community structure between inshore and offshore, and also difference between inner sites and outer sites of inshore around the water gate. Sediment characteristics (total organic carbon and nitrogen, ignition loss, and acid volatile sulfide) measured in this study also supported to this result. Therefore, this indicates that the offshore provides better benthic environments for polychaete habitation than the inshore, and the inshore around the water gate shows improving benthic environment, compared to the inner inshore.

• Radiation Oncology Journal
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• v.33 no.1
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• pp.36-41
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• 2015

Purpose: To evaluate the incidence and risk factors of post-treatment intracranial hemorrhage of brain metastases from hepatocellular carcinoma (HCC). Materials and Methods: Medical records of 81 patients who have been diagnosed of brain metastases from HCC and underwent surgery, radiosurgery and/or whole brain radiotherapy (WBRT) between January 2000 and December 2013 were retrospectively reviewed. Results: Intracranial hemorrhage was present in 64 patients (79%) at the time of diagnosis. Median value of alpha-fetoprotein (AFP) level was 1,700 ng/mL. The Eastern Cooperative Oncology Group (ECOG) performance status for 20 patients was greater than 2. Fifty-seven patients underwent WBRT and the others were treated with surgery and/or radiosurgery without WBRT. During follow-up, 12 events of intracranial hemorrhage after treatment were identified. Three-month post-treatment hemorrhage rate was 16.1%. Multivariate analyses revealed that ECOG performance status, AFP, and WBRT were associated with post-treatment hemorrhage (p = 0.013, 0.013, and 0.003, respectively). Kaplan-Meier analysis showed that 3-month post-treatment hemorrhage rate of new lesion was higher in patients treated without WBRT, although statistical significance was not reached. (18.6% vs. 4.6%; p = 0.104). Ten of 12 patients with post-treatment hemorrhage died with neurologic cause. Conclusion: WBRT should be considered to prevent post-treatment hemorrhage in the treatment of brain metastases from HCC.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.5
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• pp.643-648
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• 2005

Near infrared reflectance spectroscopy (NIRS) has become increasingly used as a rapid, accurate method of evaluating some chemical constituents in cereal grains and forages. If samples could be analyzed without drying and grinding, then sample preparation time and costs may be reduced. This study was conducted to develop robust NIRS equations to predict fermentation quality of corn (Zea mays) silage and to select acceptable sample preparation methods for prediction of fermentation products in corn silage by NIRS. Prior to analysis, samples (n = 112) were either oven-dried and ground (OD), frozen in liquid nitrogen and ground (LN) and intact fresh (IF). Samples were scanned from 400 to 2,500 nm with an NIRS 6,500 monochromator. The samples were divided into calibration and validation sets. The spectral data were regressed on a range of dry matter (DM), pH and short chain organic acids using modified multivariate partial least squares (MPLS) analysis that used first and second order derivatives. All chemical analyses were conducted with fresh samples. From these treatments, calibration equations were developed successfully for concentrations of all constituents except butyric acid. Prediction accuracy, represented by standard error of prediction (SEP) and $R^2_{v}$ (variance accounted for in validation set), was slightly better with the LN treatment ($R^2$ 0.75-0.90) than for OD ($R^2$ 0.43-0.81) or IF ($R^2$ 0.62-0.79) treatments. Fermentation characteristics could be successfully predicted by NIRS analysis either with dry or fresh silage. Although statistical results for the OD and IF treatments were the lower than those of LN treatment, intact fresh (IF) treatment may be acceptable when processing is costly or when possible component alterations are expected.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.4
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• pp.1397-1401
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• 2015

Background: To determine the expressions of Tbx3, a member of subgroup belonging to T-box family, and its prognostic value in pancreatic carcinoma. Materials and Methods: We determined the expression levels of Tbx3 on both mRNA and protein levels in 30 pairs of fresh tumor tissues and paratumor tissues by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting, respectively. In addition, protein level of Tbx3 were identified using immunochemistry in 80 pairs of paraffin-embedded specimen. The correlations between Tbx3 expression and various clinicopathological parameters as well as overall survival were evaluated. Results: Tbx3 mRNA and protein levels in tumor tissues were significantly higher than in the paratumor tissues by qRT-PCR ($0.05{\pm}0.007$ vs. $0.087{\pm}0.001$, p<0.001) and western blotting ($1.134{\pm}0.043$ vs. $0.287{\pm}0.017$, p<0.001). The statistical analysis based on immunohistochemical evaluation suggested that Tbx3 aberrant expression was significantly associated with several conventional clinicopathological variables, such as gender, age, tumor position, preoperative CA19-9 level, pathological T staging and N staging. Univariate and multivariate analyses revealed that Tbx3 expression was an independent prognostic factor for overall survival (<0.001). Conclusions: Our results suggest that overexpression of Tbx3 is associated with poor prognosis of pancreatic cancer patients. However, additional clinical trials are needed to accurately validate this observation.

• Journal of Korean Neurosurgical Society
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• v.46 no.2
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• pp.123-129
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• 2009

Objective: This study was aimed to identify the incidence and risk factors of vancomycin-resistant enterococcus (VRE) colonization in neurosurgical practice of field, with particular attention to intensive care unit (ICU). Methods: This retrospective study was carried out on the Neurosurgical ICU (NICU), during the period from January. 2005 to December. 2007, in 414 consecutive patients who had been admitted to the NICU. Demographics and known risk factors were retrieved and assessed by statistical methods. Results: A total of 52 patients had VRE colonization among 414 patients enrolled, with an overall prevalence rate of 6.1%. E. faecium was the most frequently isolated pathogen, and 92.3% of all VRE were isolated from urine specimen. Active infection was noticed only in 2 patients with bacteremia and meningitis. Relative antibiotic agents were third-generation cephalosporin in 40%, and vancomycin in 23%, and multiple antibiotic usages were also identified in 13% of all cases. Multivariate analyses showed Glasgow coma scale (GCS) score less than 8, placement of Foley catheter longer than 2 weeks, ICU stay over 2 weeks and presence of nearby VRE-positive patients had a significantly independent association with VRE infection. Conclusion: When managing the high-risk patients being prone to be infected VRE in the NICU, extreme caution should be paid upon. Because prevention and outbreak control is of ultimate importance, clinicians should be alert the possibility of impending colonization and infection by all means available. The most crucial interventions are careful hand washing, strict glove handling, meticulous and active screening, and complete segregation.

• Journal of the Korean Geographical Society
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• v.44 no.4
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• pp.532-543
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• 2009

The foodservice franchise is preferred by the founders who inaugurate a business enterprise, because it is not difficult to convert into money more than other private enterprise. The success or failure of the foodservice franchise depends 80 percent on its location. Therefore, this research aimed to study the location factors of the first shops of foodservice franchise in Seoul through the analyses of nearest neighborhood effect and statistical relationship between variables. According to there results, the location characteristics of the first shops of foodservice franchise are summarized as in the following three items. First, the spatial distribution pattern of the first shops is a clustered type. Second, the first shops relate to the 15 variables which are the number of financial facilities, the number of business service offices, and the number of hotels and restaurants, etc. Third, the main location factor of the first shops is the number of financial facilities. In conclusion, it is estimated that Gangnam-gu and Jung-gu might be good for the location of the first shops of foodservice franchise in Seoul, because these two places have many financial buildings.

• Journal of Periodontal and Implant Science
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• v.50 no.4
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• pp.260-267
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• 2020

Purpose: The aim of this study was to compare the prevalence, amount, and rate of supraeruption of the maxillary second molar according to sex, age, and history of periodontitis. Methods: Data were collected retrospectively from the charts and panoramic radiographs of 65 patients who were scheduled to undergo implant placement at the site of the mandibular second molar. The amount of supraeruption of the maxillary second molar and the alveolar bone level of the neighboring teeth were measured on digital panoramic radiographs. The prevalence was evaluated in each group, and univariate and multivariate logistic regression analyses were used to identify factors influencing the prevalence of supraeruption. The amount and the rate of supraeruption were compared between pairs of groups using the Mann-Whitney U test. For all tests, P values <0.05 were considered to indicate statistical significance. Results: Supraeruption occurred in 78% of the patients. The prevalence of supraeruption was affected by sex, age, and history of periodontitis. The mean amount of supraeruption was 0.91 mm and the mean rate of supraeruption was 0.14 mm/month. The amount and the rate of supraeruption showed no significant differences according to sex, age, or the distance from the cementoenamel junction to the alveolar bone crest (P>0.05). Conclusions: These results show that the amount of supraeruption on the maxillary second molar was similar to the thickness of the enamel on the occlusal surface. When a single implant is scheduled to be placed on the mandibular second molar, supraeruption of the antagonist should be considered.

• Journal of Ginseng Research
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• v.42 no.3
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• pp.277-287
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• 2018

Background: Temperature is an essential condition in red ginseng processing. The pharmacological activities of red ginseng under different steam temperatures are significantly different. Methods: In this study, an ultrahigh-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry was developed to distinguish the red ginseng products that were steamed at high and low temperatures. Multivariate statistical analyses such as principal component analysis and supervised orthogonal partial least squared discrimination analysis were used to determine the influential components of the different samples. Results: The results showed that different steamed red ginseng samples can be identified, and the characteristic components were 20-gluco-ginsenoside Rf, ginsenoside Re, ginsenoside Rg1, and malonyl-ginsenoside Rb1 in red ginseng steamed at low temperature. Meanwhile, the characteristic components in red ginseng steamed at high temperature were 20R-ginsenoside Rs3 and ginsenoside Rs4. Polar ginsenosides were abundant in red ginseng steamed at low temperature, whereas higher levels of less polar ginsenosides were detected in red ginseng steamed at high temperature. Conclusion: This study makes the first time that differences between red ginseng steamed under different temperatures and their ginsenosides transformation have been observed systematically at the chemistry level. The results suggested that the identified chemical markers can be used to illustrate the transformation of ginsenosides in red ginseng processing.

• The Korean Journal of Applied Statistics
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• v.30 no.1
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• pp.135-145
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• 2017

Principal component analysis (PCA) describes the variation of multivariate data in terms of a set of uncorrelated variables. Since each principal component is a linear combination of all variables and the loadings are typically non-zero, it is difficult to interpret the derived principal components. Sparse principal component analysis (SPCA) is a specialized technique using the elastic net penalty function to produce sparse loadings in principal component analysis. When data are structured by groups of variables, it is desirable to select variables in a grouped manner. In this paper, we propose a new PCA method to improve variable selection performance when variables are grouped, which not only selects important groups but also removes unimportant variables within identified groups. To incorporate group information into model fitting, we consider a hierarchical lasso penalty instead of the elastic net penalty in SPCA. Real data analyses demonstrate the performance and usefulness of the proposed method.