• Title/Summary/Keyword: maximum resistance

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Studies on the Effects of Atmospheric Pollution in Sericulture -Injuries of Sulphur Dioxide and Cadmium on Parent Silkworms Rearing- (대기공해가 양잠에 미치는 영향에 관한 연구 -원잠종 사육에 있어서 아황산 가스 및 카드미움의 해를 중심으로-)

  • 이종철;최진협;배계선;손흥대
    • Journal of Sericultural and Entomological Science
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    • v.21 no.1
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    • pp.36-44
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    • 1979
  • Those studies were examined rearing two varieties on Japanese descent and two varieties of Chinese descent by feeding polluted mulberry leaves, non-polluted ones and water-cleaned ones respectively to find effects of air-pollution on the economic characters of silkworms and analysis of contents of Sulphur and Cadmium in the mulberry leaves and silkworms as followings; 1) Japanese descent of polluted part was delayed about 2.5 days than non-polluted part, Chinese descent was delayed about 4 days or inequal and water-cleaned part was medium in the silkworm larval duration. 2) Results of maximum weight of 5th instal, cocoon layer weight and cocoon weight were decreased in due order non-polluted, water-cleaned and polluted in the factors of mulberry 3) Pupal ratio of Japanese descent was not shown statistical significance, but Chinese descent was revealed it obviously in the factors of mulberry leaves. 4) In the resistance of polluted mulberry leaves, Chinese descent was feeble obviously than Japanese and there were some difference even through among the same varieties. 5) The content of S and Cd of polluted area mulberry leaves was increased about 30% respectively than non-polluted area. 6) The fed part of non-polluted mulberry leaves was S 0.41% and Cd 0.013 ppm water-cleaned part was S 0.47% and Cd 0.024 ppm and polluted part was S 0.52% and Cd 0.042 ppm in the contents of S and Cd of silkworm larvae. 7) The contents of S and Cd didn't make visible injury in mulberry leaves but made it seriously in silkworm larvae. 8) The injury of dust on mulberry leaves was more serious than that of quality of mulberry leaves by air-pollution in the economic characters of silkworm. 9) As above results, Chinese descent should avoid contaminated area and it rearing by water-cleaned mulberry leaves can get noticable results in inevitable case on selection of parents silkworm rearingzone.

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Selecting Appropriate Seedling Age for Restoration Using Comparative Analysis of Physiological Characteristics by Age in Abies koreana Wilson

  • Seo, Han-Na;Chae, Seung-Beom;Lim, Hyo-In;Han, Sim-Hee;Lee, Kiwoong
    • Journal of Forest and Environmental Science
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    • v.37 no.4
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    • pp.315-322
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    • 2021
  • The aim of this study was to investigate the sensitivity to environmental stress, and changes in the photosynthesis capacity in Abies koreana seedlings by age and to suggest the most effective age for restoration. To identify these physiological characteristics of A. koreana, the chlorophyll fluorescence and photosynthetic capacity of 1-, 2-, 3-, 5- and 6-year-old A. koreana seedlings were observed from June 2020 to June 2021. The maximum quantum efficiency of Photosystem II (Fv/Fm), a chlorophyll fluorescence measurement parameter, was strongly positively correlated with the monthly average temperature (1-year-old seedling: r=0.8779, 2-year-old seedling: r=0.8605, 3-year-old seedling: r=0.8697, 5-year-old seedlings: r=0.8085, and 6-year-old seedlings: r=0.8316). The Fv/Fm values were the lowest in winter (November 2020-March 2021). In addition, the Fv/Fm values of 1-, 2-, and 3-year-old seedlings in winter were lower than that of 5- and 6-year-old seedlings, while the Fv/Fm values in summer were relatively higher than those in winter. Further, the Fv/Fm values of seedlings of all ages decreased in August 2020, when the monthly average temperature was the highest. In particular, 1-year-old to 3-year-old seedlings showed Fv/Fm values less than 0.8. Further, the photosynthetic capacity measured in August 2020 increased with increasing seedling age. The analysis of variance results for summer Fv/Fm values showed significant differences in age-specific averages (p<0.05), and Duncan's multiple range test showed significant differences between 5- and 6-year-old seedlings and 1-, 2-, and 3-year-old seedlings (p<0.05). These results suggested that the 5- and 6-year-old seedlings were less sensitive to environmental stress and showed better photosynthetic capacity than the 1-, 2-, and 3-year-old seedlings. Therefore, 5-year-old or older A. koreana seedlings can be used as restoration materials because they can show increased adaptability and stable growth during transplantation due to their relatively high environmental resistance and photosynthetic capacity.

The Characteristics of Progenies derived from Lilium lancifolium and Asiatic hybrid "Dreamland" (참나리와 Asiatic hybrid "Dreamland"의 교잡 후대 특성)

  • Park, In-Sook;Suh, Dong-Hee;Hwang, Yoon-Jung;Park, Song-Kyung;Kang, Si-Yong;Rhee, Hye-Kyung;Lim, Ki-Byung
    • Korean Journal of Breeding Science
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    • v.41 no.4
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    • pp.451-455
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    • 2009
  • Lilium lancifolium, which is one of the Korean native lilies, possesses several useful genetic characteristics such as growth vigor, bulbil formation and resistance to Fusarium. Hybridization was performed to insert useful traits of Asiatic hybrid "Dreamland" as the male parent with upward direction and dark brown spotless on the petal into L. lancifolium as the female parent. The rate of pollen germination of L. lancifolium and "Dreamland" were 30% and 60%, respectively. The pollen germination ratio of $F_1$ progenies at flowering date was 25-57%, which is between the parents'pollen germination ratio. The individual flowering time was between 113 days and 131 days after planting. Of 99% of all plants, the leaf shape index was more than five, which means that the leaf shape of $F_1$ plants is more influenced by female than male parent. The flower color was separated into four types. 51.5% of the progenies showed orange and 44.2% showed light orange, respectively. The colors seemed to be highly influenced by female parents. Mixed colors of parents, orange yellow and light yellow orange, were 3.1%, 1.2%, respectively. Flowering directions were segregated by three different ways, upside, side, and downside. Side direction, which is medium type between female and male parent, was 73%. All progenies showed lots of spot on petals except one offspring. The percentage of bulbil formation on leaf axil was 49.4%. Among those, the maximum number of bulbil formation was 25. The mean number of bulbil formation per plant was five.

Anti-obesity Effects and Safety of the Mixture of Herbal Extracts in 3T3-L1 Cells and HR-1 Mice Fed a High Fat Diet (3T3-L1 지방전구세포와 고지방 식이로 유도된 비만 HR-1 마우스 피부에 도포한 한약 추출 복합물의 항비만 효과 및 안전성 평가)

  • Jeong, Eui Seon;Park, So Yi;Lee, Ki Hoon;Na, Ju Ryun;Kim, Jin Seok;Park, Kyung Mok;Kim, Sunoh
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.32 no.6
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    • pp.384-395
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    • 2018
  • The aim of this study was to investigate whether a novel formulation of an herbal extracts has an inhibitory effect on obesity. To determine its anti-obesity effects, we performed anti-obesity-related experiments in vitro and in vivo. Thus, our present study was carried out to evaluate the anti-obesity effect of herbal extracts using a high fat diet (HFD)-induced obese mouse model and 3T3-L1 adipose cells. The effects of each herbal extracts on lipid accumulation in 3T3-L1 cells were examined using Oil Red O staining. Results showed that treatment with each herbal extracts at $10{\sim}100{\mu}g/ml$ had no effect on cell morphology and viability. Without evidence of toxicity, herbal extracts treatment decreased lipid accumulation compared with the untreated adipocytes controls as shown by the lower absorbance of Oil Red O stain. Futhermore, compared with control-differentiated mature adipocytes, each herbal extracts significantly inhibited lipid accumulation in mature 3T3-L1 adipocytes. In the HFD-fed obese mice, body weight, liver weight and white adipose tissue weights were significantly reduced by mixture of herbal extracts administration in mouse skin. Futhermore, we found that mixture of herbal extracts administration suppressed serum triglyceride (TG), and total cholesterol (TCHO) in HFD-induced obese mouse model. The mixture of herbal extracts of permeability was estimated by measuring the transepithelial electrical resistance (TEER) value in pig skin. The optimized formulations of herbal extracts (Test 3 formulation) showed skin permeation. However, test 1 formulation containing essential oil as enhancer showed maximum skin permeation. After confirming the enhanced skin permeability, in vivo studies were performed to assess whether skin irritation potential on the basis of a primary irritation index (PII) in rabbit skin. Reactions were scored for erythema/edema reactions at 24 h, 48 h and 72 h post-application. It was concluded that the test 1 formulation was not irritation (PII = 0). The present study suggests that the test 1 formulation might be of therapeutic interest with respect to the treatment of obesity.

Optimization of anode and electrolyte microstructure for Solid Oxide Fuel Cells (고체산화물 연료전지 연료극 및 전해질 미세구조 최적화)

  • Noh, Jong Hyeok;Myung, Jae-ha
    • Korean Chemical Engineering Research
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    • v.57 no.4
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    • pp.525-530
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    • 2019
  • The performance and stability of solid oxide fuel cells (SOFCs) depend on the microstructure of the electrode and electrolyte. In anode, porosity and pore distribution affect the active site and fuel gas transfer. In an electrolyte, density and thickness determine the ohmic resistance. To optimizing these conditions, using costly method cannot be a suitable research plan for aiming at commercialization. To solve these drawbacks, we made high performance unit cells with low cost and highly efficient ceramic processes. We selected the NiO-YSZ cermet that is a commercial anode material and used facile methods like die pressing and dip coating process. The porosity of anode was controlled by the amount of carbon black (CB) pore former from 10 wt% to 20 wt% and final sintering temperature from $1350^{\circ}C$ to $1450^{\circ}C$. To achieve a dense thin film electrolyte, the thickness and microstructure of electrolyte were controlled by changing the YSZ loading (vol%) of the slurry from 1 vol% to 5 vol. From results, we achieved the 40% porosity that is well known as an optimum value in Ni-YSZ anode, by adding 15wt% of CB and sintering at $1350^{\circ}C$. YSZ electrolyte thickness was controllable from $2{\mu}m$ to $28{\mu}m$ and dense microstructure is formed at 3vol% of YSZ loading via dip coating process. Finally, a unit cell composed of Ni-YSZ anode with 40% porosity, YSZ electrolyte with a $22{\mu}m$ thickness and LSM-YSZ cathode had a maximum power density of $1.426Wcm^{-2}$ at $800^{\circ}C$.

An Analytical Study on Composite Beam Performance with Post-Fire Temperature Using ANSYS Program (ANSYS를 이용한 화재 후 온도에 따른 합성보 성능에 관한 해석적 연구)

  • Kwak, Sung-Shin;Choi, Byong-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.1
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    • pp.391-400
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    • 2019
  • In the case of fire, a structure loses its original stiffness due to the temperature rise, and the load bearing capacity decreases. The loss of structural strength increases with increasing fire time of the structure. To prevent the collapse of buildings, it is very important to understand whether or not the members are damaged. On the other hand, there is insufficient data to be a guideline for diagnosing and evaluating the residual strength of the members in Korea. Therefore, this study examined the resistance performance by Finite-Element-Analysis of composite beams, which are composite structures among structural members. Composite beam modeling was carried out based on the model used in the Electrical Penetration Room (EPR) in cooperation with KEPCO. The heat transfer analysis and structural analysis of the critical phase were performed using ANSYS, a finite element analysis program. ANSYS was used to perform heat transfer analysis and structural analysis at the static analysis. To analyze the residual performance, the temperature distribution of the composite beam and the maximum displacement result of the heat-affected structure analysis were derived and the experimental data and the structural analysis result data were compared and analyzed.

A Study on the Ventilation Effects of the Shaft Development at a Local Limestone Mine (국내 석회석 광산 수갱 굴착에 의한 통기효과 분석 연구)

  • Lee, Changwoo;Nguyen, Van Duc;Kubuya, Kiro Rocky;Kim, Chang O
    • Tunnel and Underground Space
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    • v.28 no.6
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    • pp.609-619
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    • 2018
  • This study was carried out at a local limestone mine to analyze the ventilation efficiency of the shaft equipped with a main fan. The results show that its ventilation efficiency is clearly verified for the natural as well as the mechanical ventilation. The airflow rate of $11.7m^3/s$ was induced by the natural ventilation force and the maximum quantity is almost same as the airflow rate estimated by monitoring the average temperatures in the upcast and downcast air columns. Meanwhile, the airflow rate exhausted by the main fan through the shaft was $20.3{\sim}24.8m^3/s$; variation of the quantity was caused by the upward shift of the mine ventilation characteristic curve due to the frequent movement of the equipment. This indicates efforts are required to reduce the ventilation resistance and raise the quantity supplied by the main fan. The turbulent diffusion coefficients along the 1912 m long airway from the portal to the shaft bottom was estimated to be $15m^2/s$ and $18m^2/s$. Since these higher coefficients imply that contaminants will be dispersed at a faster velocity than the airflow, prompt exhaust method should be planned for the effective air quality control. The ventilation shaft and main fan are definitely what local limestone mines inevitably need for better working environment and sustainable development.

Impact of NR1I2, adenosine triphosphate-binding cassette transporters genetic polymorphisms on the pharmacokinetics of ginsenoside compound K in healthy Chinese volunteers

  • Zhou, Luping;Chen, Lulu;Wang, Yaqin;Huang, Jie;Yang, Guoping;Tan, Zhirong;Wang, Yicheng;Liao, Jianwei;Zhou, Gan;Hu, Kai;Li, Zhenyu;Ouyang, Dongsheng
    • Journal of Ginseng Research
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    • v.43 no.3
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    • pp.460-474
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    • 2019
  • Background: Ginsenoside compound K (CK) is a promising drug candidate for rheumatoid arthritis. This study examined the impact of polymorphisms in NR1I2, adenosine triphosphate-binding cassette (ABC) transporter genes on the pharmacokinetics of CK in healthy Chinese individuals. Methods: Forty-two targeted variants in seven genes were genotyped in 54 participants using Sequenom MassARRAY system to investigate their association with major pharmacokinetic parameters of CK and its metabolite 20(S)-protopanaxadiol (PPD). Subsequently, molecular docking was simulated using the AutoDock Vina program. Results: ABCC4 rs1751034 TT and rs1189437 TT were associated with increased exposure of CK and decreased exposure of 20(S)-PPD, whereas CFTR rs4148688 heterozygous carriers had the lowest maximum concentration ($C_{max}$) of CK. The area under the curve from zero to the time of the last quantifiable concentration ($AUC_{last}$) of CK was decreased in NR1I2 rs1464602 and rs2472682 homozygous carriers, while $C_{max}$ was significantly reduced only in rs2472682. ABCC4 rs1151471 and CFTR rs2283054 influenced the pharmacokinetics of 20(S)-PPD. In addition, several variations in ABCC2, ABCC4, CFTR, and NR1I2 had minor effects on the pharmacokinetics of CK. Quality of the best homology model of multidrug resistance protein 4 (MRP4) was assessed, and the ligand interaction plot showed the mode of interaction of CK with different MRP4 residues. Conlusion: ABCC4 rs1751034 and rs1189437 affected the pharmacokinetics of both CK and 20(S)-PPD. NR1I2 rs1464602 and rs2472682 were only associated with the pharmacokinetics of CK. Thus, these hereditary variances could partly explain the interindividual differences in the pharmacokinetics of CK.

Discharge Computation from Float Measurement in Vegetated Stream (부자 측정 시 식생을 고려한 유량산정에 관한 연구)

  • Lee, Tae Hee;Jung, Sung Won
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.39 no.2
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    • pp.307-316
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    • 2019
  • Development of vegetation in stream channel increases resistance to flow, resulting in increase in river stage upon flood and affecting change in stage-discharge relationship. Vegetation revealed in stream by water level reaching a peak and then declined upon flood is mostly found as prone. Taking an account of flow distribution with the number of vegetation, prone vegetation layer might be at height where discharge rate is zero (0) (Stephan and Guthnecht, 2002). However, there is a tendency that flow rate is overestimated when applying the height of river bed to flow area with no consideration of the height of vegetation layer in flow rate by float measurement. In this study, reliable flow measurement in stream with vegetation was calculated by measuring the height of vegetation layer after flood and excluding the vegetation layer-projected area from the flow area. The result showed the minimum 4.34 % to maximum 10.82 % of flow deviation depending on the scale of discharge. Accordingly, reliable velocity-area methods would be determined if vegetation layer-projected area in stream is considered in flow rate estimation using the flow area during the flood.

P=Comparative Analysis of Thermal Performance According to Combines of Multi-layer Insulating Curtain (다겹보온커튼의 조합에 따른 열성능의 비교 분석)

  • Jin, B.O.;Kim, H.K.;Ryou, Y.S.;Lee, T.S.;Kim, Y.H.;Oh, S.S.;Moon, J.P.;Kang, G.C.
    • Journal of the Korean Society of Mechanical Technology
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    • v.20 no.6
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    • pp.763-769
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    • 2018
  • In this research, in order to improve the heat retention of greenhouse, comparative analysis of the heat flux of the marketed multi-later insulating curtain was carried out. Experiments is conducted by fabricating a test apparatus for investigating the heat flux characteristics. The multi-later insulating curtain used for the experiment was compared using the P, N, S, U and T company, which are commercially available, and the heat flux due to temperature difference between the experimental apparatus and the outside was compared and analyzed. When the internal temperature of the experimental result is the maximum temperature $60^{\circ}C$, the heat flux of multi-later insulating curtain is T Co.($73.1W/m^2$) > S Co.($119.5W/m^2$) > U Co.($155W/m^2$) > N Co.($163.1W/m^2$) > P Co.($177.7W/m^2$). The heat flux means the quantity of heat passing through the unit time per unit area, and the higher the numerical value, the higher the quantity of heat passing through the multi-layer insulating curtain. This can be determined that high heat fluxes produce low heat resistance. Further, it has been found that the weight of the insulating curtain is largely unrelated to the heat insulating property, and the heat insulating curtain having a thickness containing a high internal air layer is excellent in the heat insulating property. In the future when manufacturing a heat insulating curtain, It is judged that it is desirable to manufacture a combination of heat insulating materials that contain a high internal air layer content and that can maintain the air layer even for long-term use while minimizing the volume.