• Journal of Genetic Medicine
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• v.8 no.1
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• pp.44-52
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• 2011

Purpose: Cytogenetic analysis of spontaneous abortions (SABs) provides valuable information to establish the causes of fetal loss, information that is essential to provide accurate reproductive and genetic counseling couples. Such analysis also provides information on the frequencies and types of chromosomal abnormalities and associated risks of recurrence. However, there have only been a few reports of chromosomal abnormalities in small samples of SABs in the Korean population. Here, we report the incidence and spectrum of chromosomal abnormalities for cases of 470 SAB in Korea. Material and Methods: Between 2005 and 2010, a total of 470 products of conception (POC) resulting from SABs were submitted to our laboratory for cytogenetic analysis from various medical sites in Korea. The incidences and types of specific chromosomal abnormalities were determined. The abnormalities were distinguished by gestational age at the time of SAB and by maternal age. Results: The frequency of chromosomal abnormalities in POCs was 54.3% (255/470), including 228 (89.3%) numerical and 27 (10.7%: 3 balanced and 24 unbalanced) structural abnormalities. Among the numerical abnormalities, trisomy was predominant (67.0%), followed by monosomy X (12.5%), polyploidy (8.2%), triple X (0.8%), and autosomal monosomy (0.8%). The overall sex ratio (male: female) among the 470 POCs with normal and abnormal karyotypes were 0.58 and 0.65, respectively. Trisomies were identified for each autosome, with the exceptions of 1, 3, and 19. Among the 171 autosomal trisomies, trisomy 16 was the most common (19.9%), followed by trisomy 22 (13.5%), trisomy 21 (12.3 %), trisomy 15 (9.9%), and trisomies 18 and 13 (5.3%). The frequency of chromosomal abnormalities decreased with gestational age and increased with maternal age, but only because of increases in trisomies and complex abnormalities. Conclusions: We have presented a large collection of cytogenetic data for SABs collected during the past 6 years and provided a database for prenatal genetic counseling of parents who have experienced SABs in Korea.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.690-695
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• 2012

Gas hydrate is an inclusion compound consisting of water and low molecular weight gases, which are incorporated into the lattice structure of water. Owing to its promising aspect to application technologies, gas hydrate has been widely studied recently, especially $CO_2$ hydrate for the CCS (Carbon Capture and Storage) issue. The key point of $CO_2$ hydrate technology for the CCS is how to produce gas hydrate in an efficient and economic way. In this study, we have tried to study the characteristic of gas hydrate formation using micro-sized ice through an ultrasonic nozzle which generate 2.4 MHz frequency wave. $CO_2$ as a carrier gas brings micro-sized mist into low-temperature reactor, where the mist and carrier gas forms $CO_2$ hydrate under $-55^{\circ}C$ and atmospheric pressure condition and some part of the mist also remains unreacted micro-sized ice. Formed gas hydrate was average 10.7 of diameter at average. The starting ice particle was set to constant pressure to form $CO_2$ hydrate and the consumed amount of $CO_2$ gas was simultaneously measured to calculate the conversion of ice into gas hydrate. Results showed that the gas hydrate formation was highly suitable because of its extremely high gas-solid contact area, and the formation rate was also very high. Self-preservation effect of $CO_2$ hydrate was confirmed by the measurement of $CO_2$ hydrate powder at normal and at pressed state, which resulted that this kind of gas storage and transport could be feasible using $CO_2$ hydrate formation.

• Journal of Technologic Dentistry
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• v.17 no.1
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• pp.82-108
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• 1995

인력은 한 사회에 있어서 자본을 축적하며 자연자원을 개발하고 사회 경제 정치적 조직을 성장시키는 변화요인으로, 인간을 중심으로 하는 사회경제적 자원을 종합적으로 지칭하는 말이다. 이렇게 국가 사회가 필요로 하는 인력을 정부가 적절히 계획하여, 형성시키며, 배분 및 활용하는 문제를 논리적이고 일관성 있게 다루는 것을 인력정책이라 한다. 이러한 거시적이고 대 사회적인 정부의 인력정책은 국민의 건강과 생명을 보호하기 위한 보건의료 서비스를 제공해야 하는 의료인력을 대상으로 하는 경우 그 중요성이 더욱 특별하다 할 것이다. 국민에 대한 보건의료 서비스는 훈련된 보건 인력에 의해서 제공되며, 국가의 인력정책의 결과로 나타나는 보건의료인력 공급의 적합성은 인력의 불균형이라는 개념들을 통해서 검토될 수 있다. 의료인력의 불균형이라 함은 의료인력의 수, 종류, 기능, 분포, 질 등과 의료서비스에 대한 국민의 전체적 요구에 대응하여 정부가 생산하여 채용, 지원, 유시할 수 있는 정부 능력의 한계를 의미한다. 다시 말해서 국민에 대한 의료서비스의 적정화는 잘 훈련된(well qualified) 의료인력이 충분히 공급되어야(adequately supplied) 하고, 또한 적절히 분포되어야(well distributed) 한다는 양적, 질적, 그리고 분포의 세 가지 측면에서 살펴볼 수 있다. 질적, 양적, 그리고 분포의 불균형이라는 범주를 통하여 살펴본 치과기공사 분야의 인력정책에 대한 연구 결과와 개선방안은 다음과 같다. 첫째, 수적 불균형의 면에서 치과기공사의 인력은 1970년대 중반이래 계속 과잉 공급되어 왔으며, 이에 대해 정부는 그동안 소극적으로 대처하므로 과잉공급을 가속시켜왔다. 따라서 이러한 과잉공급을 최소하기 위해서는 치과이용에 대한 수요의 확장, 무면허자의 취업규제단속 및 대학의 치과기공학과 정원 축소 등을 생각해 볼 수 있다. 이러한 외형상의 과잉공급에도 불구하고 현업에 종사하는 실제인력은 수용에 비해 부족한 과소 공급현상을 빚고 있다는 점이 문제이다. 이러한 역설적인 현상을 타파하기 위하여 무면허자의 적발을 위시한 제도적 장치가 마련되어야 한다. 둘째, 질적 불균형은 수적 과잉공급에 의한 취업률 저하로 인한 실력 있는 전문인력 확보의 어려움과 전문 교육인력 및 교육시설의 열악한 조건이 원인으로 지적될 수 있으며, 이에 대한 해결방안으로 적절한 인력수요의 조절과 교육인력 및 시설 여건의 향상이 요망된다. 예컨대 3년제로 되어있는 학제를 4년제로 상향조정하는 방안을 고려할 수 있다. 세째, 치과기공사 분야의 인력분포 불균형은 그다지 심각하지는 않은 것으로 나타난다. 그러나 변화하는 소득수준과 사회환경은 의료인력과 균등한 지역적 분포에 대해 지속적인 관심을 가질것을 요청한다고 할 것이다. 이를 위하여 현재의 공중보건의 제도처럼 치기공 분야의 인력을 무의촌지역에 배치하여 공익요원으로 봉사케 하는 제도를 생각해 볼 수 있다.

• Applied Microscopy
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• v.36 no.2
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• pp.83-91
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• 2006

The number and structure of synapses are dynamically changed in response to diverse physiological and pathological conditions. Since strength of synaptic transmission is closely related to the synaptic density on a neuron, both synaptogenesis and synapse loss may play important roles in controlling neuronal activity. Thus it is essential to estimate the number of synapses using an accurate quantitative method for better understanding of the numerical alteration of synapses under terrain experimental conditions. We applied physical disector principle to estimating the number of synapses per neuron in the dentate gyrus of adult mice. First, we measured the numerical density of granule cells using the physical disector principle. Second, the density of medial perforant path to granule cell synapses was estimated using the bidirectional physical disector. Then, the volume ratio of molecular layer to granule cell layer was measured. With these numerial values, we successfully calculated the number of synapses per neuron. Individual granule cells have approximately 6500 synapses in the dentate gyrus of adult mice $(6,545{\pm}330)$, which are comparable to those of other researchers. Our results showed that the estimation of synapse numbers per neuron using the physical disector principle would provide accurate and precise information on the numerical alteration of synapses in diverse physiological and pathological conditions. Following analyses of synapse numbers using this method will contribute to the better understanding of structural synaptic plasticity in a variety of experimental animal models.

• Korean Journal of Ecology and Environment
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• v.39 no.3 s.117
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• pp.390-401
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• 2006

This study was conducted to understand the phytoplankton-zooplankton trophic linkage in Lake Paldang ecosystems (Paldang Dam and Kyungan Stream) from April to December 2005. Zooplankton were filtered as two size groups (microzooplankton (MICZ): 60{\sim}20\;{\mu}m$, macrozooplankton (MACZ): >$200\;{\mu}m$), and their clearance rates and C-fluxes on phytoplankton were measured. Grazing experiments were performed in the laboratory with the different zooplankton densities (0, 2, 4, 8x of ambient density, n=2). Diatoms, such as Aulacoseira and Cyclotella were dominant phytoplankton taxa at both sites. Among phytoplankton communities, total carbon biomass of phyflagellates was much higher than others at both sites. Rotifers numerically dominated zooplankton community, while cladocerans dominated carbon biomass. Both phytoplankton and zooplankton density and biomass were high in spring, but decreased markedly after summer monsoon season. plankton biomass at Kyungan Stream was significantly higher than that of Paldang Dam. Zooplankton clearance rate and amount of C-flux were relatively high in the spring and then decreased after summer at both sites. Seasonal change of C-flux was similar to that of zooplankton biomass (P<0.001, n=7). MACZ clearance rate and C-flux were higher than those of MICZ. Water residence time and physical disturbance in summer appeared to affect zooplankton grazing on phytoplankton at the study sites. Our results indicate phytoplankton were an important energy source for zooplankton in Lake Paldang ecosystem. Furthermore, C-flux of plankton food web is affected by not only biological components but also physical parameters.

• Journal of Life Science
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• v.21 no.8
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• pp.1199-1203
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• 2011

The present study evaluated the beneficial effects of polycalcium (a mixture of Polycan and calcium lactate-gluconate 1:9 [g/g]) on osteoporosis using in vitro assays. Cell proliferation and alkaline phosphatase activities of osteoblasts (human primary osteoblasts) and osteoclast differentiation of RAW264.7 cells (murine osteoclast progenitor cells) treated with different concentrations of polycalcium for various periods were assessed. Osteoblast proliferation was stimulated and prevented RANKL-induced osteoclast differentiation of RAW264.7 cells. These results support the development of ideal anti-osteoporotic agents, such as polycalcium, that exhibit properties that accelerate bone formation and inhibit bone resorption.

• Applied Microscopy
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• v.31 no.3
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• pp.275-285
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• 2001

The pulmonary alveolar macrophage is thought to play an important role in the mediation of acute inflammatory lung injury by secretory products including degraded enzymes, cytokines, and reactive oxygen metabolites . This study was conceived to understand the role of alveolar macrophage in oxidative stress induced acute lung injury. To examine the alveolar macrophages and xanthine oxidase (XO) activity in bronchoalveolar lavage fluid (BALF), time-dependent changes of numbers of alveolar macrophages, monocytes and neutrophils in alveolar cavity were counted in association with ultrastructural and cytochemical observations of lung tissue and alveolar cells. The number of monocytes was increased (p<0.001) at 1h after IL-1 treatment compared with that of sham. At 2h after instillation of IL-1, the number of alveolar macrophages was the highest, XO activity in BALF was elevated at 2h after IL-1 instillation and the activity was markedly elevated(p<0.05) at 3h after IL-1 treatment. On the basis of these experimental results, it is suggested that, during early phase of acute lung injury induced by IL-1, alveolar macrophage-derived XO contributes to lung injury earlier than the neutrophilic respiratory burst.

• Journal of the Korean Society of Costume
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• v.33
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• pp.55-72
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• 1997

우리나라 복식산업의 전문인력 양식은 주로 대학교나 전문학원에서 이루어지고 있으며 수적인면에서는 충분한 인력이 양성되고 있다. 그러나 질적인 면에서 산업체에서 요구되는 역량을 가진 전문인은 부족한 편이다. 이에 따라 산업체의 요구에 부합하는 인력야성을위하여 교육과정의 개선이 절실히 요구되고 있다. 따라서 본 연구에서는 실기교육 산학협력 및 산업체 현장실습이 활발히 이루어지고 있는 영국의 복식관련학과에 대하여 조사해 봄으로써 우리 교육의 개선방향을 모색하고자 한다. 영구의 경우 다양한 자격증 및 학위과정이 개설되어있으나 본 연구에서는 우리나라 학사학위에 해당되는 BA 및 Bsc만대상으로 하였으며 설문조사 문헌조사 및 사례연구를 통하여 현황 및 교과과정을 분석하였다 영국의 복식관련학과들은 그 교과과정 및 내용에 따라 크게 6개 전공분야로 분류되었으며 각 하과는 다시 세분화되어 전문성이 있는 교육이 이루어지고 있었다 또한 수업연한 및 과정의 형태에 따라 5개 유형으로 분류되었다, 이유형 중 특히 일년간의 현장실습을 학위과정으로 포함시켜 의무적으로 산업체에 근무하도록 되어있는 Sandwic Mode는 적극적인 산학협력의 한 형태로 매우 효율적으로 평가되는 교육체계이며 여러다른 학문 분야에서도 널리 활용되고 있는 체계이다. 교수진의 경우 전임교원이 수적인 면에서 다소 부족한 것으로 나타났으나 관련 산업체 인사 등을 시간강사로 고용함으로써 이를 보완 할 뿐 아니라 산학연계를 이루고 있었다. 또한 전임교원의 경우 주로 학사 혹은 석사의 학력을 가지고있었다. 그러나 모든 전임교수 뿐 아니라 시간강사의 경우도 산업체 경력을 필수 적으로 가지고있어 고학력위주의 우리나라 실정과는 매우 상이했다. 교과과정에 대한 사례연구에서 직물디자인에 집중된 2개 과의 교과과정을 보았으며 그중 한 개 과는 다시 편물 프린트 및 직물 디자인의 3분야로 세분화되어 심도 있는 교육이 이루어질 수 있는 것을 살펴보았다 또한 다른 3개의 예에서 볼수있듯이 2개 이상의 전공코스를 도입하여 공통과목과 전공 코스 과목을 둠으로써 시설 및 인적 자원의 활용 등 운영상 효율성을 추구함을 알수 있었다 또한 학생들의 경우 전문화된 코스의 선택을 할수 있게 하였다 이런 실례는 전문인력양성이 매우 필요하고 따라서 전공코스제의 도입의 필요성이 대두되고 있는 이시점에서 매우 유용하게 이용될수 있으리라고 생각된다. 영구의 교육이 우리나라 실정에 그대로 적용될 수는 없지만 본 연구 결과를 바탕으로 다음과 같은 시사점을 고려하여 우리교육을 개선해 나갈 수 있으리라고 생각한다. 첫째 교수진 인적 물적상황 및 지역적 상황등을 분석하여 각 대학별로 그 특성에 맞는 세분화되고 심도있는 전공교육과정을 개발 발전시켜 야 할 것이다 둘째 산업체 방문 산업체인사와의 면담 및 특강 등 산학협력을 좀더 적극적으로 모색하여야 할 것이다. 셋째 학생들의 산업체 현장 연수를 실질적으로 도입하여 산업체의 인력요구에 적극적으로 대처 할수 있어야 하겠다.

• The Korean Journal of Pesticide Science
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• v.8 no.4
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• pp.288-298
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• 2004

Benzimidazole pesticide carbendazim that is effective against a wide range of fungal plant pathogens is a protective, eradicant, and systemic fungicide. For genetic toxicity evaluation of carbendazim on DNA, genes and chromosome, were investigated with chromosome aberration, bacterial reverse mutation, micronucleus test in mouse born marrow and DNA damage assay by single cell microgel electrophoresis. Substitution and frameshift mutation were not induce at variable concentration of carbendazim on Ames test with or without rat liver microsomal activation. For the result of chromosome aberration test, numerical changes of chromosome were detected at the concentrations higher than $4.0{\mu}g/m{\ell}$, but structural aberration was not induced. Positive control, Mitomycin-C and captafol made a structural aberration, but numerical change of chromosome did not appear. In the micronucleus test for mouse born marrow, carbendazim was negative, but was weak positive in DNA damage assay by single cell microgel electrophoresis because of increased DNA moving length of 20% to control.

• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.156-160
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• 2000

The Plasma film treated with a high electric voltage was developed to enhance flow down of condensation drops on inside plastic film. Arch type greenhouse framed with iron pipe of 25mm diameter defand 1.5mm thickness were covered with either the developed plasma film or surfactant film(control). Green pepper seedlings raised for 40 days in plug trays were transplanted at a density of 110cm by 30cm in each greenhouse. The mount of condensational water on film surface, generated by 7$0^{\circ}C$ water bath chimney systems and flew down, was collected and measured. The amount of collected water after 150 minutes was 2.56 mL.100c $m^{-2}$ and 0.94mL.100c $m^{-2}$ , respectively, in the plasma film and surfactant film-covered greenhouses. The amount of condensational water drops attached on the cover at 08:20 a.m. at 60 days filter covering was 0.34mL.100c $m^{02}$ and 0.32mL.100c $m^{-2}$ , respectively, in the plasma film- and surfactant film-covered greenhouses. Solar irradiance transmitted into greenhouse was 2.0% higher in the greenhouse covered with the plasma film tan that in the greenhouse covered with the surfactant film. Air temperature in the plasma film-covered greenhouse was higher than the surfactant film-covered greenhouse by 0.5$^{\circ}C$. However, there was no difference in relative humidity between the two greenhouse. Plant height, leaf area, dry weight and early yield showed no significant differences.s.