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Chromosome Studies on Several Wild Sepcies of Drosophilidae (야생 초파리 수종의 염색체에 관한 연구)

  • 강영선;김영진;방규환
    • The Korean Journal of Zoology
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    • v.7 no.2
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    • pp.13-18
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    • 1964
  • The chromosomes of thirteen wild forms of Drosophila obtained from Kwangnung in Kyunggi Province, Korea were investigated with the ganglion cells of both male and female larvae using the aceto-lactic orcein squashed method. The male chromosome patterns of the species observed in the present study are summarized as follows:

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PREVALENCE OF STREPTOCOCCUS MUTANS AND STREPTOCOCCUS SOBRINUS IN CHILDREN UNDER 6 YEARS OF AGE (6세 이하의 어린이에서 Streptococcus mutans와 Streptococcus sobrinus의 분포에 관한 연구)

  • Ahn, Seung-Tae;Park, Jae-Hong;Lee, Keung-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.32 no.2
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    • pp.207-216
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    • 2005
  • Mutans streptococci have been reported to be implicated in dental caries. Of these streptococcal species, Streptococcus mutans and Streptococcus sobrinus are most commonly found in human dental caries. Prevalence of these bacterial species in dental caries is found to be varied in different races and countries. Therefore, importance of these bacteria in dental caries remains to be determined. The present study was peformed to detect S. mutans and S. sobrinus in 52 Korean children with dental caries between 2 to 6 years of age. For the study, plaque samples were collected from caries-active(CA) and caries-free(CF) teeth of each subject. DNA was extracted from the plaques and amplified by polymerase chain reaction(PCR) using primers corresponding to dex and gtf genes. The results obtained from the study were as follows: 1. Of 52 children, 37 children (71.2%) were found to harbor S. mutans and/or S. sobrinus. 2. Of the MS-infected 37 children, 3 children (5.8%) harbored S. mutans and/or S. sobrinus in the CF plaques only, 22 children (42.3%) in the CA plaques only and 12 children (23.1%) in both CF and CA plaques. 3. S mutans and/or S. sobrinus were detected in 34 CA plaques (65.4%), while 15 in CF plaques (28.8%) 4. In the case of CF plaques, 8 plaques (15.4%) were observed to harbor S. mutans only, 6 plaques (11.5%) to harbor S. sobrinus only and 1 plaque (1.9%) to harbor both species. 5. Of CA plaques, 24 plaques (46.2%) were detected to have S. mutans only, 2 plaques (3.8%) to have S. sobrinus only and 8 plaques (15.4%) to have both species. 6. In comparison with the efficiency of two different primers for PCR, it was found that the primer based on gtf gene was more effective in detecting S. mutans, while the primer corresponding to dex gene was better for S. sobrinus. Overall results suggest that MS appears to be important in dental caries of the Korean children, and S. mutans is more closely associated with than dental caries as compared to S. sobrinus.

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Synthesis and Characterization of Square Planar Mixed-Ligand Complexes (II) : Electrophilic and Nucleophilic Reaction of M(S-S)(N-N) Type Complexes with Ni(II), Pd(II), and Pt(II) (평면사각형 혼합 리간드 착물의 합성과 그 특성 (제 2 보) : Ni(II), Pd(II) 및 Pt(II)의 M(S-S)(N-N)형 착물의 친전자성 및 친핵성 반응)

  • OH Sang Oh;Chung Duck Young
    • Journal of the Korean Chemical Society
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    • v.36 no.1
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    • pp.81-86
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    • 1992
  • The electrophilic and nucleophilic reactions of M(S-S,ph)(N-N,H) (M = Ni(II), Pd(II), Pt(II); (S-S,ph) = 1,2-diphenylethylenedithiolate; (N-N,H)=1,10-phenanthroline) complexes have been investigated. Reaction with norbornadiene depended upon the back donating ability of the central metal ion and produced 2,5-dithia-3,4-diphenyl-tricyclo[4,4,1,0]-undeca-3,8-diene. In the reaction with methyl iodide, the effect of cleavage of (N-N,H) ligand affected the yield of methylated $M(S-S,ph)_2$ product. The structure of the thermolysis product, ${\alpha},{\alpha}{\prime}$-bismethylthiostibene $(CH_3S-SCH_3,ph)$ of methylated complexes indicates that the main product of the nucleophilic reaction is $M(CH_3S-SCH_3,ph)(S-S,ph)$. We have synthesized a new mixed-ligand complex M(S-S,CN)(N-N,H)((S-S,CN) = 1,2-dicyanoethylenedithiolate) through the nucleophilic reaction of ligand.

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THE INHIBITORY EFFECT OF FRUCTAN-PRODUCING S. SALIVARIUS ON THE FORMATION OF ARTIFICIAL PLAQUE (Fructan 생성 S. salivarius의 인공치태 억제효과)

  • Park, So-Yung;Park, Eun-Hae;Oh, Jong-Suk;Yang, Kyu-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.30 no.1
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    • pp.25-32
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    • 2003
  • S. mutans is the most important causative bacteria of dental caries among the oral bacteria. S. salivarius is a normal inhabitant in the human oral cavity. Nine strains of S. salivarius in this study were isolated from the oral cavities of children and identified, and their effect on S. mutans and S. oralis was studied. 1. The mean weight of produced artificial plaque on the wires in the beaker was 204.9 mg in the culture of S. mutans only, whereas being reduced to 1.9 mg through 20.6mg in the combined culture of S. mutans and each S. salivarius isolate (p<0.05). The viable cell didn't show the difference between them after culturing. 2. When S. mutans was cultured in the media containing culture supernatant of each S. salivarius isolate in M17 broth, the mean weight of produced artificial plaque was 117.1 mg on the wires, whereas being 47.7 mg in the media containing culture supernatant of each S. salivarius isolate in M17 broth containing 5% sucrose. 3. The polymer produced by S. salivarius isolates was on the thin layer chromatography. 4. Inulin and levan didn't inhibit the formation of artificial plaque by S. mutans in the beaker test. These results suggested that fructan-producing S. salivarius isolates inhibited the formation of artificial plaque by S. mutans.

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A Study for Reductive Degradation and Surface Characteristics of Hexachloroethane by Iron Sulfide ($FeS,\;FeS_{2}$) (황화철($FeS,\;FeS_{2}$)을 이용한 헥사클로로에탄의 환원적 분해반응과 표면특성에 관한 연구)

  • Park Sang-Won;Kim Sung-Kuk;Heo Jae-Eun
    • Journal of Soil and Groundwater Environment
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    • v.11 no.5
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    • pp.35-42
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    • 2006
  • The following results were obtained in the reductive degradation of hexachloroethane (HCA), and surface characteristics by using iron sulfide ($FeS,\;FeS_{2}$) mediators. HCA was degraded to pentachloroethane (PCA), tetrachloroethylene(PCE), trichloroethylene(TCE) and cis-l,2-dichloroethylene (cis-1,2-DCE) by complicated pathways such as hydrogenolysis, dehaloelimination and dehydrohalogenation. FeS had more rapid degradation rates of organic solvent than $FeS_{2}$. In liquidsolid reaction, the reaction rates of organic solvents were investigated to explain surface characteristics of FeS and $FeS_{2}$.. To determine surface characteristics of FeS and $FeS_{2}$, the specific surface area and surface potential of each mineral was determined and the hydrophilic site ($N_{s}$) was calculated. The specific surface area ($107.0470m^{2}/g\;and\;92.6374m^{2}/g$) and the $pH_{ZPC}$ of minerals ($FeS\;PH_{ZPC}=7.42,\;FeS_{2},\;PH_{ZPC}=7.80$) were measured. The results showed that the Ns of FeS and $FeS_{2}$ were $0.053\;site/mm^{2}\;and\;0.205\;site/mm^{2}$, respectively. $FeS_{2}$ had more hydrophilic surface than FeS. In other words, FeS have more hydrophobic surface site than $FeS_{2}$.

A Study on the Charateristics of the Korean Adult Female Sound According to Sasang Constitution Using PSSC with a Sentence (사상체질음성분석기(四象體質音聲分析機)(PSSC)를 통한 한국인 성인여성(成人女性)의 체질별(體質別) 음향특성연구(音響特性硏究) - 단문(短文)을 중심으로 -)

  • Youn, Ji-Young;Yoon, Woo-Young;Cho, Sung-Eon;Wang, Hyang-Lan;Jeon, Jong-Weon;Kim, Dal-Rae;Yoo, Jun-Sang
    • Journal of Sasang Constitutional Medicine
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    • v.18 no.3
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    • pp.75-93
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    • 2006
  • 1. Objectives and Methods Sasang Constitutional Medicine is the original Korean Medicine. The purpose of this study was to objectify the diagnosis of Sasang Constitution. 212 Women's sentences were analyzed into 228 factors like Pitch, APQ, Shimmer, Octave and Energy, etc. Women's sentences were classified into 3 categories: total group, under 54 years old group and over 55 years old group. 2. Results 1) In Total group Soyangin's Center feq.(3) was significantly high compared with Taeyangin and Taeumin groups. Taeumin's Pitch2 was significantly high compared with Soeumin and Taeyangin groups. Taeyangin's Pitch S.D. was significantly high compared with Soyangin group. Taeyangin's Octave6 was significantly high compared with Soeumin group. There were no significant differences among constitutional groups in APQ and Shimmer segment. On the point of Energy, Taeyangin's G Tot E(1), G# Tot E(1), G dev.(1), G# dev.(1), G Tot E(2), G# Tot E(2), G dev.(4) and G# dev.(4) were significantly high compared with other groups. Soyangin's A#S.D.(2) was significantly high compared with Taeyangin group. Taeyangin's A#S.D.(3) was significantly high compared with Taeumin group. Taeyangin's F S.D.(5), F# S.D.(5) and Max Average were significantly high compared with Soeumin group. Taeumin's Peak3 and Peak4 were significantly high compared with Taeyangin group. Taeumin's PeakValue1 was significantly high compared with Soeumin group. Taeyangin's PeakValue2 was significantly high compared with Soeumin group. Taeyangin's PeakValue3 and PeakValue5 were significantly high compared with Other groups. 2) In Under 54 years old group, there were no significant differences among constitutional groups in APQ, Shimmer and Octave segment. Taeumin's Center freq.(2) was significantly high compared with Taeyangin and Soyangin groups. Taeumin's Pitch(2) and Pitch(3) were significantly high compared with Taeyangin and Soeumin groups. Taeyangin's and Taeumin's Pitch S.D. were significantly high compared with Soyangin group. Taeyangin's and Soyangin's Octave2 were significantly high compared with Taeumin group. On the point of Energy, Taeyangin's and Soyangin's A# S.D.(2) were significantly high compared with Soeumin group. Taeyangin's and Soyangin's G# dev.(1), G# dev.(2) were significantly high compared with Taeumin group. Taeyangin's and Taeumin's F# S.D.(3) were significantly high compared with Soeumin group. Taeyangin's and Soyangin's Max Average were significantly high compared with Soeumin group. Taeumin's Peak3 was significantly high compared with Taeyangin and Soeumin groups. Taeyangin's and Taeumin's PeakValue2 were significantly high compared with Soeumin group. Taeyangin's and Soeumin's PeakValue3 were significantly high compared with Taeumin group. Taeyangin's and Soyangin's PeakValue5 were significantly high compared with Soeumin group. Taeyangin's and Soyangin's PeakValue9 were significantly high compared with Taeumin group 3) In Over 55 years old group, there were no significant differences among constitutional groups in Pitch, APQ, and Peak segment. Soeumin's F Shimmer(1) and F Shimmer(2) were significantly high compared with Taeyangin and Taeumin groups. Soeumin's G# Shimmer(1) and G# Shimmer(2) were significantly high compared with Soyangin group. Taeyangin's Octave5 and Octave6 were significantly high compared with Soeumin group. On the point of Energy, Soyangin's C S.D., F# S.D.(1), F# S.D.(2) and G dev.(2) were significantly high compared with other groups. Soyangin's F# S.D.(3) was significantly high compared with Taeumin and Soeumin groups. Taeyangin's and Taeumin's G# S.D.(2) and G# S.D.(3) were significantly high compared with Soyangin group 3. Conclusions From above result, there is the possibility of efficient standard guide for constitution diagnosis by analysis of voice

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The Relationship between Social Competence and Popularity in Children (아동의 사회적 능력과 인기도간의 관계)

  • Han, Seong Hee
    • Korean Journal of Child Studies
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    • v.9 no.1
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    • pp.81-91
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    • 1988
  • The present research studied the relationship between children's social competence and popularity and examined popularity variables for the prediction of children's social competence. The subjects of this study were 80 children, 40 boys and 40 girls at age 5. Children's social competence was measured by the children's teachers with the use of the Social Competence Scale (Kohn & Rossman, 1972). Children's popularity and unpopularity were obtained from the subjects with the use of Moore's (1973) Sociometric Status Test. Teacher's estimate of the popularity of children was obtained with the use of Connolly & Doyle's (1981) Teacher Rankings of Popularity. The analysis of the data was by Pearson's Correlation Coefficient, and Stepwise Multiple Regression. There were significant relationships between children's social competence and popularity (children's popularity, children's unpopularity, teacher's popularity). Teacher's estimate of child's popularity was the best variable with which to predict children's social competence, the second best variable was children's popularity as measured by Moore's Sociometric Test.

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Children's Self-Control : Effects of Mother's Parenting and Children's Reflection (어머니의 양육행동과 유아의 사려성이 유아의 자기통제행동에 미치는 영향)

  • Kang, Gi Sook;Lee, Kyung Nim
    • Korean Journal of Child Studies
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    • v.22 no.4
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    • pp.115-132
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    • 2001
  • This study examined the effects of mother's parenting and children's reflection on the development of self-control in the resistance to temptation situation. Subjects were 85 3-, 4- and 5- year old children attending educational preschool and their mothers. Each subject's activities were videotaped for 10 minutes in the experimental settings. Children's reflection was evaluated by Kagan's Matching Familiar Figures Test(MFF). Mothers completed a parenting questionnaire. Results showed no age or sex difference in resistance to temptation. Task patience increased with age, and girls had more task patience than boys. Children's resistance to temptation and task patience correlated with children's reflection and mother's parenting. Children's MFF latency and mother's permissiveness-nonintervention predicted children's resistance to temptation. Children's MFF errors, sex, age and mother's warmth-acceptance predicted children's task patience.

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Structural Equational Modeling for Mother's Child-Bearing Behavior (어머니 양육행동의 관련변인에 대한 구조분석)

  • 정현희
    • Journal of the Korean Home Economics Association
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    • v.41 no.6
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    • pp.75-90
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    • 2003
  • The present study investigated causal relationship between child's temperament, mother's parental satisfaction, mother's marital satisfaction and mother's child-rearing behavior according to child's sex. The subjects for this study were 473 children and their's mothers of first-second grade selected from elementary schools in Busan. Han's questionnaires(1996) on child's temperament, Hyun's questionnaires(1994) on parental satisfaction, Choi's questionnaires(1994) on marital satisfaction and Hong's questionnaires(1996) on mother's child-rearing behavior were used. Data were analyzed with Manova, Pearson's correlation, Lisrel 8.5. The results were as follows : (1) According to sex, there were significant differences in mother's marital satisfaction and child-rearing behavior. The mothers of girls showed higher marital satisfaction. And boys perceived higher limit-setting and higher responsiveness. (2) For boys, mother's parental satisfaction and marital satisfaction revealed direct effect on mother's child rearing behavior. For girls, tempeament and parental satisfaction revealed direct effect on mother's child rearing behavior.