• 대한수학회보
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• 제26권1호
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• pp.47-52
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• 1989

Methods of Riemannian geometry has played an important role in the study of compact transformation groups. Every effective action of a compact Lie group on a differential manifold leaves a Riemannian metric invariant and the study of such actions reduces to the one involving the group of isometries of a Riemannian metric on the manifold which is, a priori, a Lie group under the compact open topology. Once an action of a compact Lie group is given an invariant metric is easily constructed by the averaging method and the Lie group is naturally imbedded in the group of isometries as a Lie subgroup. But usually this invariant metric has more symmetries than those given by the original action. Therefore the first question one may ask is when one can find a Riemannian metric so that the given action coincides with the action of the full group of isometries. This seems to be a difficult question to answer which depends very much on the orbit structure and the group itself. In this paper we give a sufficient condition that a subgroup action of a compact Lie group has an invariant metric which is not invariant under the full action of the group and figure out some aspects of the action and the orbit structure regarding the invariant Riemannian metric. In fact, according to our results, this is possible if there is a larger transformation group, containing the oringnal action and either having larger orbit somewhere or having exactly the same orbit structure but with an orbit on which a Riemannian metric is ivariant under the orginal action of the group and not under that of the larger one. Recently R. Saerens and W. Zame showed that every compact Lie group can be realized as the full group of isometries of Riemannian metric. [SZ] This answers a question closely related to ours but the situation turns out to be quite different in the two problems.

• 농촌지도와개발
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• 제29권4호
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• pp.225-250
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• 2022

This study aims to examine the effects of infant's social development forest experience activities through meta-analysis. The final nine studies(total of 165 in the experimental group and 159 in the control group) were selected as a method of systematic review. Meta-analysis on overall effect size estimation, chi-square test, significance analysis, publication bias analysis, and subgroup analysis was performed using the R program. The overall effect size of 9 studies was 1.59, indicating a large effect size. As a result of subgroup analysis of the sub-factors of sociality, autonomy showed the largest effect size at 1.47, the adjusted effect size of cooperation was 1.34, the effect size adjusted for peer interaction was 1.29, and the adjusted effect size for perspective-taking ability was 0.97. All were found to have a statistically significant effect. To analyze the moderating effect, a meta-regression analysis was conducted on the participation period(4, 5~6, 7~8weeks), the number of sessions(6~10, 11~15, 16~20), the frequency per week(1, 2, 5), and the participation time(40, 60, 90, 120, 150min), but there was no statistical difference. Although not statistically significant, the effect size was larger when the participation period was 4 weeks, the number of sessions was 16 to 20, the frequency was 2 times per week, and the participation time was 40 minutes. This results can be usefully utilized by policy makers and forest commentators related to the vitalization of forest education through forest experience activities.

• Investigative Magnetic Resonance Imaging
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• 제16권1호
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• pp.16-24
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• 2012

목적: Dixon 정량 화학적 변위 자기공명영상(QCSI)의 척추 골수 지방함량과 이중에너지 방사선 흡수법 (DXA)를 통한 BMD 값과의 상관성을 알아본다. 대상과 방법: QCSI와 간의 화학적 변위영상을 포함한 전신 자기공명영상(MRI)과 요추의 DXA를 시행한 68명의 건강한 사람들[평균연령, 50.7세; 범위, 25-76세; 남/여=36/32]을 대상으로 후향적 연구를 시행하였다. 성별과 T-score에 따라 정상(남/여=27/23)과 골감소증(남/여=9/9)집단으로 나누고, MRI로 척추골수와 간의 지방함량을 측정하였다. 각 집단의 나이, 체질량지수(BMI), 골수 지방함량과 간의 지방함량을 비교하였고, 여성에서는 폐경 전후 각 변수들의 비교를 추가하여 Spearman's 상관계수로 평가하였다. 결과: 남성의 나이, BMI, 척추 골수와 간의 지방함량은 정상과 골감소증 집단 사이에 큰 차이를 보이지 않았다. 여성에서는, 골감소증 집단의 평균 나이가 정상집단에 비해 높았고(p=0.01), 폐경된 경우가 많았으나[폐경 전, 26.1%(6/23); 후, 77.8%(7/9); p<0.05], 다른 변수들은 유의한 차이를 보이지 않았다. 골수 지방함량과의 비교에 있어 여성의 나이는 유일한 의미 있는 변수였다(r=0.43, p<0.05). 결론: Dixon QCSI를 통한 척추 골수 지방함량의 측정은 남녀 모두에 있어 DXA BMD 감소를 정확히 반영하지는 않는다.

• Fisheries and Aquatic Sciences
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• 제15권2호
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• pp.125-135
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• 2012

This study was carried out to understand the correlation between phylogenetic relationships based on 18S rDNA sequences and growth by salinity of Chlorella-like species. The 18S rDNA sequences of 71 Chlorella-like species which were mainly collected from Korean waters were analyzed. The 18S rDNA sequences of Chlorella-like species were divided into three groups (group A, B and C) and group B was further divided into three subgroups (subgroup B-1, B-2 and B-3). Thirty-seven Chlorella-like species in group A grew well at high salinity (32 psu) but the other groups grew well in freshwater. The sequence identities of the species in group A and B were 97.2-99.5%, but those of 6 species in group C ("Chlorella" saccharophila), which contained group I intron sequences region were 75.0-75.4%. Two representative species of each group were cultured at different salinities (0, 16 and 32 psu) to examine the correlation between the molecular phylogenetic groups and the phenotypic characteristics on cell growth and size by different salinities. The size of cell cultured at different salinities varied according to the species of each molecular phylogenetic group. The size of "Chlorella" saccharophila in group C was bigger and more obviously elliptical rather than that of the other Chlorella-like species. Considering the results on molecular and phenotypic characteristics, the group A and B belonged to Chlorellaceae, but group C was distinctly different from them.

• Asian Pacific Journal of Cancer Prevention
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• 제15권17호
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• pp.7251-7255
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• 2014

MicroRNAs (miRNAs) act as tumor suppressors or promoters in neoplasia by regulating relative geneexpression. The association between a single nucleotide polymorphism (SNP) rs4938723 in miR-34b/c and susceptibility to cancers was inconsistent in previous studies. In this study, we conducted a literature search of PubMed, Web of Science and Embase to identify all relevant studies in this meta-analysis with 6,036 cases and 6,204 controls. We found that the miR-34b/c rs4938723 polymorphism was significantly associated with increased risk of cancers in the heterozygous model (TC versus TT, OR=1.09, 95% CI=1.01-1.18, P=0.02). Subgroup analysis also revealed increased risk for Asian ethnicity in the heterozygous model (TC versus TT, OR=1.12, 95% CI=1.02-1.22, P=0.02), but decreased risk of colorectal cancer in homozygote model (CC versus TT, OR=0.66, 95% CI=0.47-0.92, P=0.02) and in the recessive model (CC versus TC+TT, OR=0.67, 95% CI=0.48-0.93, P=0.02) by cancer type. The current meta-analysis indicated that the miR-34b/c rs4938723 polymorphism may decrease susceptibility to colorectal cancer. Well-designed studies with larger sample size are required to further validate the results.

• 한국토양비료학회지
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• 제33권4호
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• pp.275-282
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• 2000

고추 시설 재배지 토양, 근권과 근면등으로부터 형광성 pseudomonads를 분리한 후 이들 중 35균주에 대해 계통 분석을 실시하였다. 계통 분석에 이용된 분류키는 165 rDNA의 일부 염기서열로, 종 수준에서 분류동정을 실시하였다. 고추재배지로부터 분리된 형광성 pseudomonads중 P. putida group으로 분류된 균주는 17균주 였으며, 이들은 주로 비근권 토양으로부터 분리되었다. 이들은 4개의 소그룹 (subgroup I, II, III, IV)으로 분류되었으며, 소그룹 I, IV에 속한 균주는 P putida의 표준균주가 속한 소그룹 II, III의 균주와는 분류학적으로 뚜렸히 구분되는 독특한 균주들이었다. P. fluorescens로 분류된 균주는 15균주였으며, 나머지 3균주는 P. fluorescens와 P. chloraphis의 중간 그룹으로 분류되었다. 근권으로부터 분리된 균주는 대부분 P. fluorescns로 분류되었으며, 이들의 유전적 유연관계는 매우 높게 나타났다. 본보의 결과에 비추어 볼 때, 고추의 근계는 P. fluorescens의 특정 균주에 의해 정착되는 것으로 생각되었다.

• 대한통합의학회지
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• 제9권1호
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• pp.203-217
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• 2021

Purpose: The purpose of this meta-analysis was to examine the high-level evidence of the effects of manual therapy on musculoskeletal diseases. Methods: Domestic databases were searched for studies that conducted clinical trials associated with manual therapy on chronic musculoskeletal diseases. A total of 591 studies published between 2005 and 2018 were identified, with 18 studies satisfying the inclusion data. The studies were classified according to patient, intervention, comparison, and outcome (PICO). The search outcomes were items associated with pain and physical function. The 18 studies included in the study were evaluated by using the R meta-analysis (version 4.0). The quality of 18 randomized control trials was evaluated by using the Cochrane risk of bias (ROB). The effect sizes were computed as the corrected standardized mean difference (SMD). Subgroup and meta-regression analyses were also used. Egger's regression test was carried out in order to analyze the publication bias. Cumulative meta-analysis and sensitivity analysis were also conducted in order to analyze the data error. Results: The following factors showed the large effect size of manual therapy on chronic musculoskeletal diseases: pain (Hedges's g = 2.66; 95% CI = 1.47 ~ 3.85), and physical function (Hedges's g = 2.15; 95% CI: 1.22 ~ 3.08). The subgroup analysis only showed a statistical difference in the type of manual therapy (pain) and outcome (physical function). No statistically significant difference was found in the meta-regression analysis. Publication bias was found in the data, but the results of the trim-and-fill method showed that such bias did not largely affect the obtained data. Furthermore, there were no data errors in the cumulative meta-analysis and sensitivity analysis. Conclusion: This study provides evidence for the effectiveness of manual therapy on chronic musculoskeletal diseases in pain and physical function. Subgroup analysis suggests that only the type of manual therapy for pain and the type of outcome for physical function differed in effect size.

• Journal of Microbiology and Biotechnology
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• 제14권2호
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• pp.337-343
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• 2004

A bacterial strain concurrently producing extracellular chitosanase and chitinase was isolated from soil and identified as a member of the $\beta$-subgroup of Proteobacteria through its 16S rRNA analysis and some biochemical analyses. The newly discovered strain, named as KNU3, had 99% homology of its 16S rRNA sequence with chitinolytic $\beta$-Proteobacterium CTE108. Strain KNU3 produced 34 kDa of chitosanase in addition to two chitinases of 68 kDa and 30 kDa, respectively. The purified chitosanase protein (ChoK) showed activity toward soluble, colloidal, and glycol chitosan, but did not exhibit any activity toward colloidal chitin. The optimum pH and temperature of ChoK were 6.0 and $70^{\circ}C$, respectively. The chitosanase was stable in the pH 4.0 to 8.0 range at $70^{\circ}C$, while enzyme activity was relatively stable at below $45^{\circ}C$. MALDI-TOF MS and N-terminal amino acid sequence analyses indicated that ChoK protein is related to chitosanases from Matsuebacter sp. and Sphingobacterium multivorum. HPLC analysis of chitosan lysates revealed that glucosamine tetramers and hexamers were the major products of hydrolysis.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1281-1287
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• 2009

The distribution pattern of the phylum Acidobacteria, a previously uncultured bacterial group, was investigated by molecular ecological analyses of global soil samples collected from pristine ecosystems across five continents. Acidobacterial 16S rDNAs were observed in almost all soil samples, and members of acidobacterial primer group A were detected in all samples that harbored the phylum Acidobacteria. Other primer groups, Y, G, and O, showed limited distribution patterns. We further divided the primer groups into acidobacterial subdivisions (class-level). Subdivisional distribution patterns were determined by comparing the observed T-RFs with theoretical T-RFs predicted by in silico digestion of acidobacterial 16S rDNAs. Consistent with the PCR results obtained with subgroup-specific primers, T-RFLP analyses showed that acidobacterial subdivision 1 belonging to primer group A was present in the majority of the soil samples. This study revealed that the phylum Acidobacteria could be globally distributed. At the subdivisional level, acidobacterial subdivision 1 might be the most widely distributed group in this phylum, indicating that members of subdivision 1 might be adapted to various soil environments, and members belonging to other subdivisions might be restricted to certain geographic regions or habitats.

• The Plant Pathology Journal
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• 제39권1호
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• pp.149-157
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• 2023

Phytoplasmas were discovered in diseased Elaeocarpus sylvestris trees growing on Jeju Island that showed symptoms of yellowing and darkening in the leaves. Leaf samples from 14 symptomatic plants in Jeju-si and Seogwipo-si were collected and phytoplasma 16S rRNA was successfully amplified by nested polymerase chain reaction using universal primers. The sequence analysis detected two phytoplasmas, which showed 99.5% identity to 'Candidatus Phytoplasma asteris' and 'Ca. P. malaysianum' affiliated to 16SrI and 16SrXXXII groups, respectively. Through polymerase chain reaction-restriction fragment length polymorphism (RFLP) analyses using the AfaI (RsaI) restriction enzyme, the presence of two phytoplasmas strains as well as cases of mixed infection of these strains was detected. In a virtual RFLP analysis with 17 restriction enzymes, the 16S rRNA sequence of the 'Ca. P. asteris' strain was found to match the pattern of the 16SrI-B subgroup. In addition, the phytoplasmas in the mixed-infection cases could be distinguished using specific primer sets. In conclusion, this study confirmed mixed infection of two phytoplasmas in one E. sylvestris plant, and also the presence of two phytoplasmas (of the 16SrI and 16SrXXXII groups) in Jeju Island (Republic of Korea).