• 제목/요약/키워드: the age of the moon

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지구의 나이: 재평가 (The Age of the Earth: Reappraisal)

  • 권성택
    • 암석학회지
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    • 제23권3호
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    • pp.273-277
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    • 2014
  • 이 논문은 지구의 나이를 알기 위한 초기의 다양한 시도를 간략히 소개하고, 운석의 납동위원소 연대측정으로 처음으로 지구의 나이가 $4,550{\pm}70Ma$임을 밝힌 Patterson (1956)의 연구를 재조명한다. 태양계 초기의 진화과정은 성운가스가 식으면서 응축되어 만들어지는 고체입자 -> 이들 입자들이 서로 들러붙어 커지는 첨합과정을 통하여 행성 크기의 물체가 생성되는 것으로 생각되고 있다. 또한 이때 생긴 원시지구가 화성 크기의 물체와 충돌하면서 그 잔해가 달을 만들었다고 생각되고 있다. 이 일련의 과정에서 지구가 생성된 시기를 꼭 집어 말하기 힘들긴 하나, 현재 지구는 이 충돌의 직접적인 결과로 생각할 수 있기 때문에 이 충돌시기를 지구의 나이로 정할 것을 제안한다. 기존 연구를 고려하면 충돌시기는 태양계에서 가장 먼저 만들어진 운석물질의 나이(즉, 태양계의 나이) $4567.30{\pm}0.16Ma$와 지구와 달 암석에서 가장 오래된 나이 $4,456{\pm}40Ma$ 사이로 개략적으로 제한될 수 있다. 이 충돌시기는 태양계 초기 행성 크기의 물체가 만들어지는 시간간격을 밝히고, 충돌 이후 생성된 지구와 달의 마그마 바다의 열 역사를 규명하는데 매우 중요하기 때문에, 앞으로 보다 정확한 충돌시기를 측정하려는 노력이 요구된다.

Multiple Infarction과 Small Artery Infarction의 독립적 위험인자로서의 Methylenetetrahydrofolate Reductase Gene Mutation (The Predictive Value of the Methylenetetrahydrofolate Reductase Gene Mutation for Multiple Infarction and Small Artery Infarction)

  • 정정욱;박정미;최병옥;김남근;오도연;정우상
    • 대한한방내과학회지
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    • 제23권1호
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    • pp.1-4
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    • 2002
  • Objective : Hyperhomocysteinemia has been proven to be an independent risk factor for stroke. The genetic mutation of methylenetetrahydrofolate reductase(MTHFR) elevates serum homocysteine level, but it still remains controversial whether the MTHFR gene mutation could be a predictor of ischemic stroke. Therefore, we studied if this genetic defect could cause ischemic stroke independently. Methods : We gathered ischemic stroke subjects and age, sex-matched controls. Age, gender, past medical history, smoking habit, serum homocysteine level, and the MTHFR genotype were recorded. General characteristics of ischemic stroke subjects were compared to the controls. We classified the stroke according to the related vessels(small and large artery infarction) and single lesion and multiple infraction. Relevant risk of the MTHFR genotype was evaluated in each stroke subtype with multiple logistic regression analysis. Results : When the controls were compared to the whole ischemic stroke, there was no specific difference except some medical histories. However, further analysis based on stroke subtypes showed important results. The small artery infarction group, multiple infraction group had significant odds ratio of the MTHFR TT genotype adjusted for age, gender, medical history and smoking habit. Conclusions : The MTHFR TT genotype is an independent risk factor for certain types of ischemic stroke, small artery infarction and multiple infarction.

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Age-stratified analysis of temporomandibular joint osteoarthritis using cone-beam computed tomography

  • Hee-Jeong Song;Hang-Moon Choi;Bo-Mi Shin;Young-Jun Kim;Moon-Soo Park;Cheul Kim
    • Imaging Science in Dentistry
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    • 제54권1호
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    • pp.71-80
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    • 2024
  • Purpose: This study aimed to evaluate age-stratified radiographic features in temporomandibular joint osteoarthritis using cone-beam computed tomography. Materials and Methods: In total, 210 joints from 183 patients(144 females, 39 males, ranging from 12 to 88 years old with a mean age of 44.75±19.97 years) diagnosed with temporomandibular joint osteoarthritis were stratified by age. Mandibular condyle position and bony changes (flattening, erosion, osteophytes, subchondral sclerosis, and subchondral pseudocysts in both the condyle and articular eminence, thickening of the glenoid fossa, joint space narrowing, and joint loose bodies) were evaluated through cone-beam computed tomography. After adjusting for sex, the association between age groups and radiographic findings was analyzed using both a multiple regression model and a multinomial logistic regression model(α=0.05). Results: The prevalence of joint space narrowing and protruded condyle position in the glenoid fossa significantly increased with age (P<0.05). The risks of bony changes, including osteophytes and subchondral pseudocysts in the condyle; flattening, erosion, osteophyte, and subchondral sclerosis in the articular eminence; joint loose bodies; and thickening of the glenoid fossa, also significantly rose with increasing age (P<0.05). The number of radiographic findings increased with age; in particular, the increase was more pronounced in the temporal bone than in the mandibular condyle (P<0.05). Conclusion: Increasing age was associated with a higher frequency and greater diversity of bony changes in the temporal bone, as well as a protruded condyle position in the glenoid fossa, resulting in noticeable joint space narrowing in temporomandibular joint osteoarthritis.

학령 전이기 유아의 학교준비도 예측요인: 만 1세 영아기 애착안정성과 의도적 통제를 중심으로 (Predictors of Preschooler Readiness for Elementary School: Focusing on Attachment and Effortful Control at Age 1)

  • 문영경;장혜주
    • 한국보육지원학회지
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    • 제15권3호
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    • pp.157-174
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    • 2019
  • Objective: The purpose of this study was two-fold: first to explore the effects of mother-child attachment and effortful control at age 1 on preschoolers' school readiness at age 6, and second, to determine the mediating effect of a child's effortful control on the relationship between mother-child attachment at age 1 in relation to school readiness at age 6. Methods: Participants in this study were 205 five-year-old toddlers(106 boys, 99 girls) recruited for the Korea Child Panel Study. Mother-child attachment was assessed using the Attachment Q-sort(Waters, 1989). Preschooler's effortful control was measured by the Early Childhood Behavior Questionnaire: ECBQ(Putnam, Gartstein & Rothbart, 2006). Preschooler's school readness was measured by the School Readiness Scale Murphey & Burns, 2002). Data were analyzed using descriptive statistics, correlations, and the structural equation modeling analysis. Results: First, mother-child attachment at age 1 effected school readiness at age 6. Effortful control at age 1 effected school readiness at age 6. Second, effortful control at age 1 mediated the effect of mother-child attachment at age 1 in relation to school readiness at age 6. Conclusion/Implications: Mother-child attachment at age 1 affects school readiness at age 6, and toddlers' effortful control at age 1 mediates the relationship between mother-child attachment in relation to school readiness at age 6.

Benign Recurrent Intrahepatic Cholestasis Type 2 in Siblings with Novel ABCB11 Mutations

  • Sohn, Min Ji;Woo, Min Hyung;Seong, Moon-Woo;Park, Sung Sup;Kang, Gyeong Hoon;Moon, Jin Soo;Ko, Jae Sung
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제22권2호
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    • pp.201-206
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    • 2019
  • Benign recurrent intrahepatic cholestasis (BRIC), a rare cause of cholestasis, is characterized by recurrent episodes of cholestasis without permanent liver damage. BRIC type 2 (BRIC2) is an autosomal recessive disorder caused by ABCB11 mutations. A 6-year-old girl had recurrent episodes of jaundice. At two months of age, jaundice and hepatosplenomegaly developed. Liver function tests showed cholestatic hepatitis. A liver biopsy revealed diffuse giant cell transformation, bile duct paucity, intracytoplasmic cholestasis, and periportal fibrosis. An ABCB11 gene study revealed novel compound heterozygous mutations, including c.2075+3A>G in IVS17 and p.R1221K. Liver function test results were normal at 12 months of age. At six years of age, steatorrhea, jaundice, and pruritus developed. Liver function tests improved following administration of phenylbutyrate and rifampicin. Her younger brother developed jaundice at two months of age and his genetic tests revealed the same mutations as his sister. This is the first report of BRIC2 confirmed by ABCB11 mutations in Korean siblings.

성인기의 노후준비의식과 노후준비행동에 관한 연구 (Study on the Perception and Behavior for Preparing their Old Age)

  • 전귀연;배문조
    • 가정과삶의질연구
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    • 제28권1호
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    • pp.13-24
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    • 2010
  • The purpose of this study were to examine the perception and behavior for preparing their old age. In order to achieve this purpose, a survey was conducted with 723 adults from Daegu and Kyungpook. Major findings of this study are as follow: First, there were statistically significantly different perception for preparing their old age according to the personal variables such as gender, age, education, marriage status, occupation and income. Second, there were statistically significantly different perception for preparing their old age according to the elderly-related variables such as taken the elder program, interests in media for elderly, the opinion on living together with the aged, contact with aged and the opinion about contact with aged. Third, there were statistically significantly different behavior for preparing their old age according to the personal variables such as gender, age, religion, education, marriage status, occupation and income. Finally, there were statistically significantly different behavior for preparing their old age according to the elderly-related variables such as taken the elder program, interests in media for elderly, the opinion on living together with the aged and the opinion about contact with aged.

중국 동북지역에서 출토된 고조선, 포여, 고구려시대의 직물 연구 (A Study on the textiles of the Age of Kojosun Booyeo and Kogooreo which were excabated in the East and Nort Area of China.)

  • 심연옥
    • 복식
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    • 제22권
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    • pp.61-70
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    • 1994
  • the purpose of study is to grasp the actual state of the textiles of Kojosun, Booyeo and Kogooryeo, by examining and studying about the excavated article of the textile of the Booyeo Age which was being gamered in the Research Institute of Study of antiquities of Civilization of gilimsung without being analyzed and examined after being excavated at September in 1990 and 1993, the textile of Kojosun Age wich was excavated and examined at East and North Gilimsung in China and the textile excavated and examined at the Kogooryeo grave at jiban China. 1. The kinds of textiles of Booye Age are warp kum plin weave silk plain weave bang gong Sa, and drawn and dyed textile, It is deemed that the real state of keum, Jeung and Hwi in the old literature of Sam guk Ji was grasped. 2. It emerges that more detailed wool than the wool fabric of China area of the same age was manufactured as the textile of Kojosun Age. hemp cloth corresponds to 12 Seung, in converting into fabric width of 50cm. 3. Keum was examined and reported as the textile of Kogooryeo Age and the real state of Woonkeum of Kogooryeo Age was grasped through "Wang ja moon keum" of Keumjang of mural of South and North I room of the grave that the same keum was excavated. The real state of dyed textile of hemp was grasped as the red hemp cloth was examined. Moreover the real state of development of advanced technique to weave with machine appeared by the grasp of inclination of loom with reed of Kogooryeo.Kogooryeo.

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어머니의 온정적 양육행동이 초등학교 1학년 아동의 학교 적응에 미치는 종단적 영향: 유아기 어머니 수용감과 또래 수용감의 직렬 매개효과 검증 (The Longitudinal Effect of Maternal Warmth on School Adjustment of First Grade Children: Testing the Serial Mediation Model of Perceived Maternal Acceptance and Peer Acceptance During Preschool Years)

  • 문영경
    • 한국보육지원학회지
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    • 제17권5호
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    • pp.43-61
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    • 2021
  • Objective: This study aimed to examine the sequential mediating effects of children's perceived maternal acceptance and peer acceptance in the relationship between maternal warmth and first grade children's school adjustment. Methods: Participants in this study were 979 seven-year-old children(498 boys, 481 girls) recruited for the Korea Child Panel Study. Data were analyzed by analyzing descriptive statistics, correlations, and significance of serial mediation pathways using SPSS 18.0 and PROCESS Macro 3.4. Results: Maternal warmth at age five effected perception of maternal acceptance at age six. Perceived maternal acceptance at age six effected perceived peer acceptance at age six. Perceived peer acceptance at age six effected school adjustment at age seven. Lastly, perceived maternal acceptance and peer acceptance at age six had a serial mediation effect between maternal warmth at age five and school adjustment at age seven. Conclusion/Implications: Perceived social acceptance during preschool years should be emphasized in order to promote school adjustment for first grade children. Parent education for promoting better parent child relationships should be considered and teachers should encourage peer play interaction to help children perceive acceptance from their peers.

당뇨병 환자와 비당뇨병 환자의 연령별 건강행태 (Health Behaviors of Diabetic and Non-Diabetic Subjects across Age Groups)

  • 김진희;추수경;문주령;송민선;김성은
    • 보건교육건강증진학회지
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    • 제27권3호
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    • pp.13-22
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    • 2010
  • Objectives: The aims of this study were to provide basic information on health behaviors of diabetics by age groups, compared to non-diabetics group. Methods: 2007 National Health Nutrition and Examination Survey Data were used to compare health behaviors between the diabetics group (191 diabetics who had been diagnosed by a doctor) and the non-diabetics group (382 general population) according to age groups. For the purpose of analysis, $x^2$-test (Fischer's exact test) and conditional logistic regression were used. Results: There were significant differences in health behaviors between the diabetics group and the non-diabetics group according to the history of health screening, BMI and alcohol consumption, and there were different pattern of health behaviors by age group. Conclusion: When developing and implementing health education and specific intervention programs for the correction of health behaviors among diabetics, one should consider age, age-adjusted health behavior patterns and priority.