• Sleep Medicine and Psychophysiology
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• v.4 no.2
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• pp.172-180
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• 1997

Objects : This study was carried out to investigate characteristics of patients who need hypnotics on the night before elective surgery as well as contributing variables for the necessity of hypnotics. Methods : After reviewing the clinical charts of patients who were scheduled to receive surgery by general anesthesia the following day, researchers had semi structural interviews with patients. In addition, Spielberger's State-Trait Anxiety Inventory(SSTAI), Beck Depression Inventory(BDI), Zung's Self-Rating Pain and Distress Scale(ZPDS), and Presleep and Postsleep Questionnaires were administered to patients. A total of 167 patients, who gave reliable information, were divided into two groups based on subjective judgement regarding the necessity for hypnotics on the night before surgery; 29 eligibles for hypnotics and 138 non-eligibles for hypnotics. Demographic and clinical characteristics of patients, some possible factors affecting sleep, psychological characteristics of patients and daytime status and nighttime sleep before surgery were compared between the two groups. In addition, discriminant function analysis was done to find the variables which would best discriminate among patients who differ in terms of necessity for hypnotics on the night before surgery. Results : There was no difference in demographic and clinical characteristics between the two groups; however, the satisfaction level with ward environment was significantly lower in the eligible group for hypnotics than the non-eligible group. Psychologically, the eligible group for hypnotics, compared to the non-eligible group, showed significantly more severe depression, pain, and distress; whereas anxiety level was not different between the two groups. For nighttime sleep before surgery, the eligible group for hypnotics, compared to the non-eligible group, expected poorer sleep before retiring and in fact, reported poorer sleep the following morning. In discriminant function analysis, 'expectation for sleep' and 'pain and distress' were the most potent contributors to discriminate the necessity of hypnotics. Conclusion : For the improvement of the patient's sleep on the night before elective surgery, giving hypnotics and/or analgesics should be determined by patient's opinion about the necessity of the drugs rather than by the therapist's own judgement or any other objective indices.

• Computational Structural Engineering
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• v.7 no.3
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• pp.95-103
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• 1994

The safety related components in the nuclear power plant should be designed to withstand the seismic load. Among these components the integrity of reactor internals under earthquake load is important in stand points of safety and economics, because these are classified to Seismic Class I components. So far the modelling methods of reactor internals have been investigated by many authors. In this paper, the dynamic behaviour of reactor internals of Yong Gwang 1&2 nuclear power plants under SSE(Safe Shutdown Earthquake) load is analyzed by using of the simpled Global Beam Model. For this, as a first step, the characteristic analysis of reactor internal components are performed by using of the finite element code ANSYS. And the Global Beam Model for reactor internals which includes beam elements, nonlinear impact springs which have gaps in upper and lower positions, and hydrodynamical couplings which simulate the fluid-filled cylinders of reactor vessel and core barrel structures is established. And for the exciting external force the response spectrum which is applied to reactor support is converted to the time history input. With this excitation and the model the dynamic behaviour of reactor internals is obtained. As the results, the structural integrity of reactor internal components under seismic excitation is verified and the input for the detailed duel assembly series model could be obtained. And the simplicity and effectiveness of Global Beam Model and the economics of the explicit Runge-Kutta-Gills algorithm in impact problem of high frequency interface components are confirmed.

• Korean Journal of Plant Resources
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• v.15 no.2
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• pp.164-171
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• 2002

Morphological characteristics and growth pattern of 10 Polygonatum collections indigenous to Korea were examined to select the promising medicinal, edible resources and horticultural crops. Plant heights of I0 collections ranged from 15 to 102cm. Stem type was ascending or erect, and node numbers per a stem was 6.2 to 23.2. Phyllotaxis type was alternate or verticillate, and leaf shape was elliptical or linear. Leave numbers per a stem was 5.2 to 63.4, and bract types were classified into bracteate and nonbracteate. Flowers bloomed from May 7 to May 30, and flowering period was 5 to 13 days. Inflorescence types were classified into racemose, corymbose, and umbellate. Flower numbers per a stem was 1.5 to 125.2, and flower length was 13.1 to 30.2㎜. Perianth shapes were classified into tubular, constrict and urceolate. Surface colors of rhizome were pale yellow, pale brown, brown, and dark brown. As a result of this experiment, P. sibiricum, P. odoratum var. pluriflorum and P. odoratum var. thunbergii were thought to be useful as the medicinal and edible resources plants. On the other hand, P. odoratum var. pluriflorum 'Variegata', and P. odoratum var. maximowiczii, P. lasianthum. P. involucratum, P. desoulavyi, P. humile, and P. inflatum were thought to be useful as horticultural plants.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.1
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• pp.113-118
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• 2010

Due to diverse soil-forming environments and different purposes of the soil classification, numerous soil classification systems have been developed worldwide. The World Reference Base for Soil Resources (WRB) and the Soil Taxonomy of the United States are well-known in Korea. However, the German Soil Systematics based on somewhat different principles from the two former systems is little-known. The objective of this paper is therefore to give a short overview of the principles of the German Soil Systematics. The German Soil Systematics consists of a six-level hierarchical structure which comprises soil divisions, soil classes, soil types, soil subtypes, soil varieties, and soil subvarieties. Soils in Germany are firstly classified into one of four soil divisions according to the soil moist regime: terrestrial soils, semi-terrestrial soils, semi-subhydric/subhydric soils, and peats. Terrestrial soils are subdivided into 13 soil classes based on the stage of soil formation and the horizon differentiation. Semi-terrestrial soils are differentiated into four classes regarding the source of soil moist: groundwater, freshwater, saltwater, and seaside. Semi-subhydric/subhydric soils are subdivided into two classes: semi-subhydric and subhydric soils. Peats are classified into two classes of natural and anthropogenic origins. Classes can be compared to orders of the U.S. Taxonomy. Classes are subdivided into 29 soil types with regard to soil forming-processes for terrestrial soils, into 17 types with regard to the soil formation for semi-terrestrial soils, into five types with regard to the content of organic matter for semi-subhydric/subhydric soils, and also into five types with regard to peat-forming processes for peats. The soil mapping units in Germany are types, which can be additionally subdivided into ca. 220 subtypes, several thousands of varieties and subvarieties using detailed nuances of morphologic features of soil profile. Soil types can be compared to great groups of the U.S. Taxonomy.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.4
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• pp.673-682
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• 2001

The use of resin composites has continued to increase over the last several years. In spite of their growing popularity, composites continue to exhibit a number of undesirable characteristics. One of the major deficiencies of composite restorative resins is their inadequate resistance to wear. Of the multitude of factors that have been associated with wear, subsurface degradation within the restoration is considered to be one. The aim of this study was to evaluate the resistance to degradation of four commercial composite resins in an alkaline solution. This solution with a high concentration of hydroxyl ions is a convenient medium for accelerated degradation of silane coupling and filler particles. The brands studies were Definite($Degussa-H\ddot{u}ls$ AG, Germany), Prodigy(Kerr, USA), Pyramid(Bisco, USA) and Synergy(Coltene, Swiss). Preweighed discs of each brand were exposed to 0.1N NaOH solution at $60^{\circ}C$. After 14 days they were removed, neutralized with HCl, washed with water and dried. Resistance to degradation was evaluated on the basis of following parameters : (a) mass loss(%)-determined from pre-and post-exposed specimen weights : (b) Si loss(ppm)-obtained from ICP-AE analysis of solution exposed to specimens; and (c) degradation $depth({\mu}m)$-measured microscopically (SEM) from polished circular sections of exposed specimens. The results were follows: 1. Mass loss of Synergy was $1.24{\pm}0.002%$, it was the highest, there was no significant difference among the materials. 2. The degree of degradation layer depth of Synergy was $107.83{\pm}2.52{\mu}m$, it was the highest, there was no significant difference among any other materials than Synergy. 3. There was no difference among the four materials in Si loss. 4. The correlation coefficient between mass loss and degradation depth was relatively high(r=0.06, p<0.05). 5. There was no coefficient correlation between Si loss and mass loss, the degree of degradation layer depth and Si loss. 6. When observed with SEM, destruction of bonding is observed between resin matrix and filler.

• 대한생식의학회:학술대회논문집
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• 2001.03a
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• pp.195-205
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• 2001

태반 영양배엽 (trophoblast)은 포유동물의 발생과정 중 가장 먼저 분화되는 세포로서, 자궁환경내에서 배아가 착상, 발생, 및 분화하기 위해서 반드시 필요한 태반을 형성하는 색심적인 세포이다. 영양배엽 세포의 분화과정중의 결함은 배아의 사산이나 임신질환 등의 치명적 결과를 초래한다. 하지만, 영양배엽 세포의 분화를 조절하는 분자생물학적인 메카니즘은 아직 규명되지 않고 있다. 영양배엽 세포의 분화를 조절하는 경로를 규경하기 위한 선결과제는 분화된 영양배엽 세포에서만 발현하는 많은 유전자들이 밝혀져야만 한다. 본 연구팀은 최근에 분화된 영양배엽 세포에서만 발현하는 두 종류의 새로운 유전자들을 찾았다. 한 종류는 homeobox를 보유하고 있는 조절 유전자 Psx이고, 다른 한 종류는 임신호르몬인 태반 프로락틴 라이크 단백질 유전자 PLP-C${\beta}$이다. 본 연구과제의 목표는 이들 유전자의 기능과 조절 메카니즘을 규명함으로써, 영양배엽 세포의 분화를 조절하는 조절경로를 밝히는 것이다. 이를 위하여 다음과 같은 일련의 연구를 수행할 것이다. 1) Psx 유전자가 분화된 영양배엽 세포에서만 발현케 하는 조절 메카니즘을 규명하기 위해 functional assays, in vitro footprinting, gel mobility shift assays, 생쥐형질전화, UV crosslinking, Southwestern blot 등의 방법을 통해 Psx 유전자의 cis-acting 요인과 trans-acting factor를 밝혀 분석한다. 2) 영양배엽 세포의 분화조절 경로를 규명하기 위해 random oligonuclotide library screening, DD-PCR, subtractive screening 등의 방법을 이용하여 Psx 유전자에 의해 조절되는 하부유전자를 밝힌다. 3) Psx 유전자를 knock-out시켜 영양배엽 세포가 발달 및 분화하는데 미치는 역할을 밝힌다. 4) Yeast two-hybrid screening방법을 이용하여 태반 프로락틴 유전자의 수용체를 찾아 이들의 신호전달 기전을 밝힌다. 제1차년 연구결과로서, mouse와 rat으로부터 각각 Psx 유전자의 genomic DNA를 클로닝하여, 유전자 구조를 비교한 결과, mouse Psx (mPsx2)는 4개의 exons으로 이루어져 있는 반면에, rat Psx (Psx3)는 3개의 exons으로 구성되어 있었다. 즉, rPsx3는 mPsx2의 exon1이 없었다. Notrhern blot과 in situ hybridization 분석에 의해 mouse와 rat에서 Psx 유전자가 다르게 발현 조절되는 현상을 밝혔다. 실제로 mPsx2와 rPsx3의 5'-flanking지역을 클로닝하여 염기서열 분석 결과 전혀 homology를 찾을 수 없었다. 또한, 이들 각각 promoter의 activity를 luciferase reporter를 이용하여 조사한 결과 Rcho-1 trophoblast cells에서 각기 다른 activity를 보여 주는 것을 발견하였다. Psx 유전자의 transcription start sites는 Primer extension에 의해 밝혔다. 또한 Psx2 유전자를 knock-out 시키기 위해 targeting vector를 Osdupde1에 제작하였다. 본 과제를 시작할 때 새로운 프로락틴 유전자 하나를 클로닝하여 이 유전자를 PLP-I라고 이름을 붙였다. 이 후 이 유전자 (PLP-I)는 PLP-C${\beta}$라고 이름을 붙이게 되었다. Mouse PLP-C${\beta}$ 유전자의 counterpart를 rat에서 찾아 염기서열을 비교한 결과 mouse와 rat에서 PLP-C${\beta}$유전자의 homology는 약 79% (amino acid level)였다. 본 연구과정을 통해 또 하나의 새로운 PLP-C subfamily member를 mouse로부터 클로닝 하였고, 이 유전자를 PLP-C${\gamma}$라 하였다. PLP-C${\beta}$와 PLP-C${\gamma}$의 발현 유형은 Northern blot과 in 냐셔 hybridization 분석에 의해 태반의 제한된 spongitrophoblast와 trophoblast giant cells에서만 발현하는 것을 밝혔다. 놀랍게도 이들 두 새로운 유전자는 alternative splicing에 의해 두 종류의 isoform이 있음을 밝혔다. PLP family member 유전자로서 splicing에 의한 isoforms을 보여 주는 유전자로는 PLP-C${\beta}$와 PLP-C${\gamma}$가 최초이다. 이들 isoform mRNAs의 발현 유형은 RT-PCR 방법을 이용하여 규명하였다. 또 하나의 새로운 발견은 PLP-C${\beta}$와 PLP-C${\gamma}$가 독특한 유전자 구조를 갖고 있었다. 즉, PLP-C${\beta}$는 exon3의 alternative splicing에 의해 5개 혹은 6개의 exons을 갖는 two isoforms이 생긴다. 반면에 PLP-C${\gamma}$는 exon2가 alternative splcing이 되면서 7개의 exons을 갖거나 6개의 exons을 갖는 isoforms을 만든다. 그리고, PLP-C${\gamma}$의 promoter activity를 trophoblast Rcho-l${\gamma}$ 세포주를 이용하여 PLP-C${\gamma}$ 의 1.5 kb 5'-flanking 지역이 trophoblast-specific promoter activity를 갖고 있음을 밝혔다. PLP-C${\gamma}$ 유전자의 transcription start site는 Primer extension에 의해 밝혔다. 제 1차 년도의 연구결과를 토대로, 2차년에서는 다음단계의 연구를 수행하고자 한다. 즉, 1) mPsx2와 rPsx3의 promoter를 비교분석 함으로서 mouse와 rat에서 Psx 유전자가 다르게 조절되는 메카니즘 규명, 2) Psx와 PLP-C 유전자의 promoter에 있는 cis-acting elements 탐색, 3) Psx2와 Psx3의 단백질을 이용하여 이들이 binding하는 target sequence 규명, 4) 제작한 Psx2 targeting vector를 이용하여 ES cells에서 Psx2 유전자 knock-out, 5) Psx 유전자를 과발현시키는 세포주를 만들고 Psx에 의해 조절되는 유전자 탐색, 6) 새로 밝히 PLP-C members 유전자들의 조절기전을 Rcho-1 세포주를 이용하여 여러 거지 성장인자와 다른 호르몬에 대한 반응을 탐색, 7) Psx와 PLP-C${\gamma}$ 유전자의 chromosomal mapping 등을 밝힐 것이다.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.199-207
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• 2016

This study was conducted to develop a forest fire occurrence model using meteorological characteristics for practical forecasting of forest fire danger rate by reflecting the climate change for the time period of 2000yrs. Forest fire in South Korea is highly influenced by humidity, wind speed, temperature, and precipitation. To effectively forecast forest fire occurrence, we developed a forest fire danger rating model using weather factors associated with forest fire in 2000yrs. Forest fire occurrence patterns were investigated statistically to develop a forest fire danger rating index using times series weather data sets collected from 76 meteorological observation centers. The data sets were used for 11 years from 2000 to 2010. Development of the national forest fire occurrence probability model used a logistic regression analysis with forest fire occurrence data and meteorological variables. Nine probability models for individual nine provinces including Jeju Island have been developed. The results of the statistical analysis show that the logistic models (p<0.05) strongly depends on the effective and relative humidity, temperature, wind speed, and rainfall. The results of verification showed that the probability of randomly selected fires ranges from 0.687 to 0.981, which represent a relatively high accuracy of the developed model. These findings may be beneficial to the policy makers in South Korea for the prevention of forest fires.

• Journal of the Mineralogical Society of Korea
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• v.22 no.4
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• pp.313-324
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• 2009

We explore the effect of particle shape and size on 3-dimensional (3D) network and pore structure of porous earth materials composed of glass beads and silica gel using NMR micro-imaging in order to gain better insights into relationship between structure and the corresponding hydrologic and seismological properties. The 3D micro-imaging data for the model porous networks show that the specific surface area, porosity, and permeability range from 2.5 to $9.6\;mm^2/mm^3$, from 0.21 to 0.38, and from 11.6 to 892.3 D (Darcy), respectively, which are typical values for unconsolidated sands. The relationships among specific surface area, porosity, and permeability of the porous media are relatively well explained with the Kozeny equation. Cube counting fractal dimension analysis shows that fractal dimension increases from ~2.5－2.6 to 3.0 with increasing specific surface area from 2.5 to $9.6\;mm^2/mm^3$, with the data also suggesting the effect of porosity. Specific surface area, porosity, permeability, and cube counting fractal dimension for the natural mongolian sandstone are $0.33\;mm^2/mm^3$, 0.017, 30.9 mD, and 1.59, respectively. The current results highlight that NMR micro-imaging, together with detailed statistical analyses can be useful to characterize 3D pore structures of various porous earth materials and be potentially effective in accounting for transport properties and seismic wave velocity and attenuation of diverse porous media in earth crust and interiors.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1278-1285
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• 2017

Accumulation of excess low density lipoprotein (LDL) cholesterol in the blood can initiate and accelerate atherosclerosis. Statins mediate the transactivation of proprotein convertase subtilisin/kexin type 9 (PCSK9), which in turn limits their cholesterol-lowering effects via LDL receptor (LDLR) degradation. The objective of this study was to investigate whether or not Allium tuberosum (AT) regulates LDLR and PCSK9. Mice were fed a low fat control diet (LD) or Western diet (WD) supplemented with AT (1%, w/w). AT significantly attenuated total and LDL cholesterol levels in mice fed WD (P<0.05). AT also significantly inhibited hepatic PCSK9 gene expression (P<0.05) while AT maintained hepatic LDLR gene expression. To further investigate AT-mediated PCSK9 regulation, HepG2 cells were treated with 10% delipidated serum (DLPS) in the presence or absence of AT. Non-toxic level of AT dose-dependently increased the LDLR protein level, and AT at $400{\mu}g/mL$ markedly inhibited PCSK9 protein expression. Similarly, AT significantly increased LDLR gene expression, whereas it significantly down-regulated PCSK9 gene expression. AT-mediated reduction of PCSK9 gene expression is likely due to decreased hepatic nuclear factor $1{\alpha}$ ($HNF1{\alpha}$) expression, but not SREBP2 in HepG2 cells under lipid-depleted conditions. AT-mediated PCSK9 inhibition contributed to LDLR protein stabilization via protection against LDLR lysosomal degradation in HepG2 cells under lipid-depleted conditions. Further investigation is warranted to determine the active components of AT and whether or not these components are effective in reducing hypercholesterolemia.

• Tuberculosis and Respiratory Diseases
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• v.60 no.6
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• pp.638-644
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• 2006

Backgrounds: This study investigated whether or not a polymorphism in the gene encoding the surfactant protein A(SP-A) has any bearing on the individual susceptibility to the development of chronic obstructive pulmonary disease(COPD) in a genetically homogenous Korean population. Methods: The genotypes of 19 COPD patients and 20 healthy neonates as controls were tested using a polymerase chain reaction followed by restriction fragment length polymorphism analysis for the SP-A gene. Results: The specific frequencies of the 6A2 and 6A18 alleles of SP-A1 and the 1A2 allele of SP-A2 were much higher in the COPD group than control group (p<0.05). However, the frequencies of the 6A3 and 6A4 alleles of SP-A1 and the 1A0 allele of SP-A2 in the COPD group were significantly lower than the control group. In the COPD group, the frequencies of the +50 locus genotypes GG of SP-A1 and the +9 locus genotypes CC of SP-A2 were 85.0% and 60.6%, respectively, and 19.7% and 24.8% in the control group, respectively. The frequencies of the polymorphic genotypes or alleles showed a statistically significant difference between the COPD group and the control group (P<0.05). Conclusion: A genetic polymorphism in SP-A is associated with the development of COPD in the Korean population.