• Title/Summary/Keyword: II-VI

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A Study on the Effect of Multi-Application of Fluoride on Enamel Remineralization (불화물 복합적용이 법랑질의 재석회화에 미치는 영향에 관한 연구)

  • Cho, Min-Jung;Lee, Hyang-Lim
    • Journal of Korean society of Dental Hygiene
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    • v.1 no.1
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    • pp.125-132
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    • 2001
  • This study was carried out to investigate the effect of multi or single application of fluoride plus 0.05% NaF solution on the remineralization of dental caries lesion. The microhardness changes of enamel surface were measured after application of fluoride and precipitation of 0.05% NaF solution on 6 groups of cow's tooth on which the artificial carious lesions were formed first. Test groups were calssified into two step application with NaF, $SnF_2$ and APF under different application time conditions plus 0.05% NaF solution(group I, II, III, IV) and single application with APF plus 0.05% NaF solution (group V) and control(0.05% NaF solution only, group IV). The obtained results were as follows. 1. Regarding microhardness change of enamel surface. microhardness increments in group I(NaF for 1 minute+APF for 3 minutes+0.05% NaF solution for 1 minute), II($SnF_2$ 1 min+APF 3 min+NaF sol.), III($SnF_2$ 2 min+APF 2 min+NaF sol.), IV(NaF 2 min+APF 2 min+NaF sol.) and V(APF 4 min+NaF sol.) were significantly greater than group VI.(P<0.05) 2. Microhardness changes of shorter application time of $SnF_2$ (group II) were significantly greater than group III. (P<0.05) 3. Microhardness changes were variable with kinds of fluoride, application sequence and application time of fluoride. but had no relation with the number of fluoride application.

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The Post-glacial Vegetation History of the Lowland in Korean Peninsula (한반도 후빙기의 저지대 식생사)

  • 최기룡
    • The Korean Journal of Ecology
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    • v.21 no.2
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    • pp.169-174
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    • 1998
  • This is the review of vegetational history of the post-glacial period in Korea. most of studies for vegetational changes are located in the lowland alluvial plain, especially below the hilly zone of western and eastern coastal regions of Korea. A couple of methods, pollen analysis and radiocarbon dating, have been employed in these studies. These results lead us to establish the pollen zonation in Korea as the followings. Yasuda et al.(1980) classified six period in Yongrang lake of sokcho. These are as follow I. 17,000-15,000yr B.P.: Picea, Abies, Pinus(Haploxylon), Larix stage, II.15,000-10,000yr B.P:Herb, Pteridophyta stage, III.10.000-6,700yr BP.:Quercus stage, IV.6,700-4,500yr B.P.:Pinus, Quercus, Carpinus stage, V.4,500-1,400yr B.P.:Quercus. Pinus stage, VI.1,400yr B.P.-present: Pinus, Herbs stage. Jo(1979) also divided the period into two stages from the outcomes of analysis done in Jumoonjin and other sites I.10,000-6,000yr B.P.:Quercus stage, II.6,000-present: Pinus-Quercus stage, and three substages: IIa.6,000-3,400 yr B.P.:lower Pinus stage, IIb.3,400-2,000yr B.P.:Pinus-Quercus stage, IIc.2,000-present: Pinus stage. Choi(1993, 1996) divided the period into three stages: I.6,000-5,000yr B.P.:Alnus, Quercus stage, II.5,000-4,000yr B.P.: Alnus, Quercus, Pinus stage, III.4,500-2,600yr B.P.: Alnus, Pinus stage. In the period around 6,000yr B.P. distinct dominant species clearly occupied the lowland of the eastern and western coasts. Thus, this strongly supports the fact that even if Korea experienced its warm and wet climate after the lateglacial, it underwent a different environmental change, dry climate, compared to the regions of Japan.

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Discrete Membranous Subaortic Stenosis (대동맥판막하 막상협착증 치험 2례)

  • 문경훈
    • Journal of Chest Surgery
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    • v.21 no.4
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    • pp.727-733
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    • 1988
  • Two cases of the discrete membranous subaortic stenosis were experienced at the Department of Thoracic & Cardiovascular Surgery, National Medical Center, Seoul, Korea. Case I was 31 years old male with a history of aortic valve replacement[Ionescu-Shiley, 19mm] at the other hospital in 1980. Heart failure was noticed 6 years later. On cardiac catheterization, pressure gradient between left ventricle 4 aorta was 104 mmHg, but subvalvular aortic stenosis was not detected by preoperative 2-D echo <% left ventriculogram. Above case revealed stenoinsufficiency of the prosthetic valve. Under the diagnosis of the prosthetic valve failure, re-do aortic valve replacement[Bjork-Shiley, 23 mm] was done. During operation, the discrete membranous subaortic stenosis was incidentally found, and it was completely resected. So we thought that above discrete membranous subaortic stenosis was not detected at first operation, and it was progressed during 6 years, and accelerated the degeneration of the prosthetic valve. Case II was 20 years old female. Her complaints were exertional dyspnea, angina, syncope, which were aggravated since 5 years ago. 2-D echo <% left ventriculogram revealed the discrete membranous subaortic stenosis. Pressure gradient was 20 mmHg, but her symptoms were serious. Associated cardiac anomaly was the persistent left superior vena cava without connection with right superior vena cava. Complete excision of the membranous tissue was done. Post-operative pressure gradient between left ventricle & aorta was absent, and her complaints were nearly subsided. Both cases were type I according to the Newfeld classification of the discrete subvalvular aortic stenosis, and complete excision of the membranous tissue was done without myotomy or mymectomy. And short-term follow-up results[Case I:2 years, Case II: 1 ~ years] were good except soft systolic murmur[grade II/VI] at the aortic area in both cases.

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Determinants and Processes of Morphological Transformation of Apartment Complexes in Busan (부산 아파트 단지 배치형태 변화의 요인과 과정에 관한 연구)

  • Lee, Sangjin;Park, SoHyu
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.35 no.3
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    • pp.91-102
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    • 2019
  • This study explores the causes and processes of morphological transformation of apartment complexes in Busan. All apartment complexes built until the year 2016 were selected for statistical analysis, drawing/map examination, field observation, selected expert interviews based on 6 periodical groups: Period I(~1990), Period II(1991~1995), Period III(1996~2000), Period IV(2001~2005), Period V(2006~2010), and Period VI(2011~2016). The research argues for three 'arrangement' types, P1U, L1U and P2U, which have dominated the whole periods occupying 88% of the total 260 complexes. The switch of the leading type represents for morphological transformation of apartment complexes. Four aspects, density(F.A.R.), height(maximum number of floors), deformed-building-type ratio, and building-orientation, have affected the change of 'arrangement' types. Density was the major cause of the arrangement-type switch, from P1U to L1U, on Period II(1991~1995). The morphological change, from type L1U to P2U, on Period V(2006~2010) was caused by height and orientation, and is correlated with the increased number of deformed-type buildings. The first phase morphological change on Period II(1991~1995) was resulted by the supply side of apartment. However, the second phase transformation on Period V(2006~2010) had gone through the complex process including reflection of consumers' demands. The significance of research is to reveal the morphological transformation process of apartment complexes through analytical investigation of the entire apartment data in Busan. The result shows that the major change of urban paysage started to occur from Period V(2006~2010), and the superficial evaluation on apartment 'being monotonous and repetitive' may not be proper at least from the perspective of town plan.

Surface characteristics and bioactivity of minocycline-treated Ti-6Al-4V alloy

  • Lee, Jung-Hyuk;Sun, Young-Gon;Na, Eui-Ri;Moon, Jong-Wook;Kim, Young-Joon
    • Oral Biology Research
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    • v.42 no.4
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    • pp.187-197
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    • 2018
  • Chemical agents such as minocycline (MC) and citric acid (CA) were suggested in the treatment of contaminated implant surface. In this study, MC-HCl treatment was performed to enhance surface characteristics of titanium alloy surface. The purpose of this study was to assess the characteristics and the biocompatibility of Ti-6Al-4V surface treated by MC. Alpha-beta titanium alloy (Ti-6Al-4V) samples were prepared and they were divided into 6 groups according to chemical concentration and treatment time. These groups include 1) group I, non-treated smooth titanium alloy; 2) group II, MC 1.5 mg/mL for 1 hour; 3) group III, MC 1.5 mg/mL for 24 hours; 4) group IV, MC 15 mg/mL for 10 minutes; 5) group V, MC 100 mg/mL for 5 minutes; 6) group VI, pH1 CA for 3 minutes. The analysis of the surface characteristics of MC-treated titanium alloy was executed using scanning electron microscopy, roughness test, and X-ray photoelectron spectroscopy (XPS). Cell adhesion and MTT assay was done using MC3T3 cell. Titanium surfaces treated with MC indicated a more smoothened surface microstructure. For group II and III, the new peaks of rutile TiO2 were found. Group II and V have more basic group of Ti-OH form in XPS. In MTT assay, all MC-treated groups showed significantly higher cell viability compared to control. The surface roughness, crystal structure, surface hydrophilicity, cell viability of smooth titanium surface was improved by MC treatment. Compared with the control experiment and CA-treated group, smooth titanium surface treated with MC showed improved surface characteristics and cell biocompatibility.

Enzyme Replacement Therapy in Patients Who Have Mucopolysaccharidosis and Are younger than 5 years old (5세 미만 뮤코다당체침착증 환자에서의 효소 대체 요법)

  • Park, Seong-Won;Son, Yeong-Bae;Kim, Se-Hwa;Jo, Seong-Yun;Ji, Seon-Tae;Jin, Dong-Gyu
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.10 no.1
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    • pp.59-66
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    • 2010
  • Enzyme replacement of therapy (ERT) is one of the most promising therapeutic strategies for the treatment of lysosomal storage disorders. ERT is available in three types of Mucopolysaccharidosis (MPS): for MPS I (Aludrazyme$^{(R)}$), MPS II (Elaprase$^{(R)}$) and MPS VI (Naglazyme$^{(R)}$) patients who are over 5 years old. But recently, early diagnosis can be done by expert clinicians and even in prenatal case. We describe the case of ERT under 5 years old MPS patients. Up to June, 2010 in Samsung Medical Center, there are 6patients who were diagnosed as MPS and started ERT under 5 years old. 3 patients were MPS I, 3 patients were MPS II. 2 patient who was diagnosed as MPS I was female and others were male. Their age at diagnosis were 4 to 37month-old (4, 13, 16, 25, 27, 37 month-old) and they are now 9 to 60 month-old (9, 39, 32, 81, 60 month-old). The youngest patient was started ERT at 4 month-old and others were started at their 13 to 49 month-old (13, 29, 27, 28, 49 month-old). First manifested symptoms of patients were macrocephaly, kyphosis and coarse face appearance. Especially, in 2 of them, one was MPS I and the other was MPS II had elder brother with same disease. And the youngest one was diagnosed by the iduronate-2-sulfatase (IDS) gene analysis from chorionic villi sampling. His mother knew that she was a heterozygous carrier of IDS gene mutation because her younger brother died from MPS II. All of them confirmed as MPS by the enzyme assay in leukocytes and fibroblast skin culture. We started ERT with ${\alpha}$-L-iduronidase(Aldurazyme$^{(R)}$) to MPS I and did recombinant human iduronate-2-sulfatase (Elaprase$^{(R)}$) to MPS II patients as recommended dose as over 5 years old. But for MPS II patient who was 4 month old, we started ERT by recombinant human IDS (Elaprase$^{(R)}$) with reduced dose 0.1 mg/kg and increased dose every 2 weeks by 0.1mg/kg up to 0.5mg/kg IV infusion. During ERT, all patients had no adverse effects and the excretion of GAGs were decreased. We have evaluated other clinical symptoms such as liver/ spleen volume, heart function and neurologic evaluation. We describe a successful ERT to MPS I and MPS II patient under 5 years old without any adverse event. It indicates that ERT in young children are well tolerated and that it has several effects which may confer clinical benefits with long-term therapy.

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The Effects of Government Intervention on Health Care System -1970-1990 in Korea- (정부개입이 의료제도에 미치는 영향 -1970-1990년을 중심으로-)

  • 이은표;문옥륜
    • Health Policy and Management
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    • v.4 no.2
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    • pp.77-110
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    • 1994
  • This study is an empiriacl analysis of effects of government intervention on the health care delivery system in Korea. The purposes of this study are to find out the effects of government intervention on the per capita national health expenditure(per capita NHE), crude mortality rate(CMR), and institutional efficiency. Here, the institutional efficiency is defined as a formula shown below: log$\frac{100-curde mortality rate }{per capita NHE}$$\times$100. The formula indicates that the instiutional efficiency increases if the CMR and/or per capita NHE goes down. In the meantime the government intervention is measured by six independent variables: I) the degree of social developments, ii) the numberr of physicians per 100, 000 population, iii) the proportion of specialists among the total physicians, iv) the proportion of public expenditure among the NHE, v) the proportion of public beds to the total number of beds, vi) the proportion of physicians working at the public sector to the total number of physicians. In the above six independent variables iv), v) and vi) are the ones that reflect the degree of government intervention. In actual calculation, the two independent variables v) and vi) are integrated into a new variable based on one to one correspondence. The materials used are the time-series data from 1970 through 1990 in Korea. A path analysis and the time-series regression analysis were adopted to estimate and examine the causal relationship between variables involved. And decomposition of the effect of causal relationship is made to find net effect, direct and indirect effect. The major findings are as follows; 1. The effect of public expenditure, number of physicians per 100, 000 population, the proportion of specialists among the total physicians and social development shows a positive relationship with per capita NHE. Only if the government intervention would be counted, the effects of the number of physicians and the proportion of specialists succeed in containing per capita NHE. 2. In additionn to the above four variables, one additional variable, per capita NHE, was also responsible for the reduction of CMR. The factor of social development found to be the most potent predictor of the CMR reduction. However, the CMR reduction due to government intervention was negligible. 3. Meanwhile, the above four variables were found to was have negative effects on the institutional efficiency. The reverse is true when the government intervention is counted. For example, the number of physicians and the proportion of specialists have played a positive role in raising institutional efficiency via goverment intervention. This comes from the factual effect that the increment of institutional efficiency via the reduction of per capita NHE is bigger than via the reduction of CMR.

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Study on suitable substrate formulation for bottle and bag cultivation of Pleurotus pulmonarius (산느타리(Pleurotus pulmonarius) 병·봉지재배에 적합한 배지조성 연구)

  • Lee, Jae-Hong;Lee, Nam-Gil;Park, Young-Hak;Mun, Youn-Gi;Jeong, Tae-Sung;Kwon, Sun-Bae;Kim, Jae-Rok;Kim, Jin-Won
    • Journal of Mushroom
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    • v.12 no.4
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    • pp.275-279
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    • 2014
  • Pleurotus pulmonarius usually grows on the dead wood of deciduous trees from mid summer to early fall. Cultivation of this mushroom is recently increasing due to its good flavour and fragrance. This study was conducted to find out the favorable substrate formulation in the bottle and bag cultivation of P. pulmonarius. The V formulation (10 : 50 : 20 : 20 mixing ratio of poplar sawdust, cottonseed hull, cottonseed meal and beet pulp) showed the fastest mycelial growth in the test tube column medium and highest yields in both bottle cultivation and bag cultivation. Those chemical conditions were pH 5.52, 29.07% organic matter contents, 1.12% total nitrogen, 25.95 OM/N ratio, 0.16% CaO, 0.51% $K_2O$, 0.17 MgO and 0.26 $P_2O_5$.

A Relations of Bone Mass Promoting Behaviors for Prevention of Osteoporosis and Multidimensional Health Locus of Control Scale Cluster (골다공증 예방을 위한 골량증진행위와 건강통제위 유형과의 관계)

  • Yeoum, Soon-Gyo
    • Women's Health Nursing
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    • v.3 no.2
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    • pp.208-223
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    • 1997
  • This study was made to suggest the nursing strategies for promoting the behaviors about bone mass health behaviors in order to prevent middle aged women's osteoporosis. This study was a descriptive-correlational design that also concerned to the types which improve bone mass promoting behaviors by inspecting patterns of health locus of control method out of recognizable variables of health improving models influencing on these bone mass promoting behaviors. For these purpose, data were collected by self reported questionnaire in middle school, from 158 women living in Seoul. The measuring tools used in this study about bone mass promoting behaviors and multidimensional health locus of control, were developed by author on the basis of literature review and analyzed by SPSS-PC window, into pearson's correlation, ANOVA, multiple regression, cluster analysis. Data was analyzed as follows. 1. 6 Multidimensional health locus of control scale clusters were existed. : a)cluster I (pure internal), b)cluster II(pure chance), c) cluster III(Believer in control), d), cluster IV(Type VI), e)cluster V(yea sayer), f) cluster VI(nay sayer). There were no findings of the powerful others external cluster and double external cluster. 2. The higher the value of internal health locus of control was, the better the bone mass promoting behaviors were(r=.2891, $p=.00^{**}$). The higher the value of chance external health locus of control was, the worse the bone mass promoting behaviors were(r=-.1367, $p=.00^{**}$). 3. On the basis of these relationships, 6 clusters were significantly different in the bone mass promoting behaviors(F=2.27, $p=.05^*$). The value of bone mass promoting behaviors was ranked the order of type VI>believer in control>pure internal>yea sayer>nay sayer>pure chance external highly. 4. Bone mass promoting behaviors were not significantly different as to age. Suggestion. Based on the results from the study, I would like to make some suggestions as follows. 1) To delay the loss of bone mass in middle aged women, the study on the cluster of the multidimensional health locus of control should be conducted repeatedly. 2) The tool of multidimensional health locus of control should be developed through a qualitative method adjusted on Korean' health culture.

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Evaluation of Experimentally Induced Lumbar Spinal Cord Injury by Somatosensory Evoked Potentials(SEPs) in Dogs (개에서 Somatosensory Evoked Potentials (SEPs)을 이용한 척수기능장애의 평가)

  • Lee, Joo-Myoung;Jeong, Seong-Mok;Kweon, Oh-Kyeong;Nam, Tchi-Chou
    • Journal of Veterinary Clinics
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    • v.18 no.4
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    • pp.315-323
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    • 2001
  • Changes in somatosensory evoked potentials (SEPs) which accompanied by insertion of foreign body in spinal canal were evaluated with clinical signs and positive contrasted myelography in dogs. Foreign bodies occupied 20∼50% of spinal canal. Foreign bodies occupying about 50% of spinal canal were inserted into the animals of group II and III for 1 week and 2 days, respectively. Foreign bodies occupying about 20% of spinal canal were inserted into the animals of group IV, V, and for 1 week, 2 days, and 8 weeks, respectively. in group I (control group), sham operation (lateral laminectomy) was performed. Group III, IV and V did not severely affect on SEPs latencies and clinical signs. Group VI affects on SEPs latencies but not on clinical signs. After foreign body removal, SEPs latencies showed similar recovery patterns with clinical signs. However, group II induced severe abnormalities in SEPs latencies and clinical signs. In group III, IV and V, thoracic potentials (TN1) were abnormally recorded after foreign body insertion and firstly/normally recorded on the 6th 9.5th and 3.5th day after foreign body (removal following) insertion. In group VI, TN1 was abnormally recorded after foreign body insertion and firstly recorded on the 7.7th day and normally recorded on 34th day after foreign body insertion. In group I, TN1 was not recorded from the 3rd day after foreign body insertion and until the 8th week after foreign body removal. In group I, TN1 was firstly recorded on the 1st day after laminectomy.

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