• Title/Summary/Keyword: natural medium

Search Result 1,275, Processing Time 0.03 seconds

Inhibitory Substance Produced by Aspergillus sp. on the Snake Proteinase - Culture Conditions for the Production of Inhibitor - (Aspergillus 속 균주가 생성하는 사독 proteinase에 대한 저해물질- 저해물질의 생산조건 -)

  • Nam Joo Hyun;Jung Hwn Seu
    • Microbiology and Biotechnology Letters
    • /
    • v.15 no.2
    • /
    • pp.135-139
    • /
    • 1987
  • Aspergillus sp. MK-24 was cultured at 3$0^{\circ}C$ in the medium consisting of 2% glucose, 0.2% NaNO$_3$, 0.02% $K_2$HPO$_4$, 0.02% MgSO$_4$ 7$H_2O$, 0.02% KCl, and at initial pH of 5.0. The production of the inhibitor on venom proteinase reached to the maximum in 7 days. Sodium nitrate or potassium nitrate as a nitrogen source was favorable. The production of inhibitor was not affected by the addition of most of the inorganic salt used but depressed by lead, zinc, cobalt, mercuric or silver salts.

  • PDF

Widdrol Blocks 3T3-L1 Preadipocytes Growth and Differentiation Due to Inhibition of Mitotic Clonal Expansion

  • Yun, Hee-Jung;Kim, Jeong-Hwan;Jeong, Hyun-Young;Ji, Hyang-Hwa;Nam, Soo-Wan;Lee, Eun-Woo;Kim, Byung-Woo;Kwon, Hyun-Ju
    • Journal of Microbiology and Biotechnology
    • /
    • v.22 no.6
    • /
    • pp.806-813
    • /
    • 2012
  • Adipocyte differentiation is strongly associated with obesity, which causes metabolic disorders. In this study, we investigated the inhibitory effects of widdrol on 3T3-L1 preadipocyte growth and differentiation. Widdrol decreased lipid droplet accumulation and down-regulated adipogenic transcription factors such as C/$EBP{\alpha}$, C/$EBP{\beta}$, and $PPAR{\gamma}$. Widdrol blocked preadipocyte proliferation and differentiation through the inhibition of mitotic clonal expansion, which was accompanied by the failure of degradation of p21, a cyclin-dependent kinase inhibitor. Cell-cycle analysis clearly indicated that widdrol actively induces cell-cycle arrest at the G1-S phage transition, causing cells to remain in the preadipocyte state. Moreover, widdrol increased p21 expression and inhibited Rb phosphorylation in preadipocyte incubated in a hormone medium. Therefore, these findings clearly suggest that widdrol blocks preadipocyte growth and differentiation through the inhibition of mitotic clonal expansion by p21-and Rb-dependent G1 arrest and can be developed as a potent anti-adipogenic agent for reducing obesity.

Effect of Salinity on the Seed Germination and Seedling Growth of Pinus densiflora for. erecta Uyeki (염도가 금강소나무의 종자발아와 유묘성장에 미치는 영향)

  • Lee, Ho-Joon;Kim, Seon-Ho
    • The Korean Journal of Ecology
    • /
    • v.12 no.4
    • /
    • pp.219-236
    • /
    • 1989
  • The effect of salinity on the seed germination and seedling growth of Pinus densiflora for. erecta Uyeki were studied under the controlled conditions in the growth chamber. The seeds were sorted into three classes in weight such as large ($15.49\pm$1.63mg), medium($10.61\pm$1.38mg), and small ($6.57\pm$1.33mg) to determine the role of seed weight in germination and seedling growth of the pine. Polymorphic seeds of the pine were germinated an salinity range of 0 to 1.5% NaCl under various temperature ($10^{\circ}$ $-25^{\circ}$ with $5^{\circ}$C interval of constant temperature, and $10^{\circ}$ $-20^{\circ}$C, $15^{\circ}$ $-25^{\circ}$C of alternating temperature) in order to determine their germinability and seeding growth. In control plot, there was little difference of germination percentage among the seed weight classes, but in saline plot, the larger seeds generally had a higher percentage and rate of germination. There occurred synergistic interaction between salinity and temperature in the germination and the increase of temperature enhanced germination of seeds at the same salinity level. Alternating temperature regimes of $15^{\circ}$-$25^{\circ}$C yielded maximum germination and no germination was occurred at $10^{\circ}C$. The germination at alternating temperature showed higher germination percentage than at constant temperature. The percentage and of germination decreased drastically with increased salinity level to 1.00%; no germination was occurred at 1.50% salinity level. The growth fo sddelings from larger seeds was better than that of smaller seeds at the same salinity and temperature. The hypocotyl and radicle were more sensitive than cotyledon to the increased salinity stress.

  • PDF

Verification of Similitude Law for 1g Shaking Table Tests through Modeling of Models (모형의 모형화 기법을 이용한 1g 진동대 실험을 위한 상사법칙의 유효성 검증)

  • Hwang Jae-Ik;Kim Sung-Ryul;Jang In-Sung;Kim Myoung-Mo
    • Journal of the Korean Geotechnical Society
    • /
    • v.20 no.9
    • /
    • pp.91-103
    • /
    • 2004
  • A series of shaking table model tests were performed to verify the validity of similitude law, which is suggested by lai (1989) to simulate the dynamic behavior of soil-fluid-structure system for is shaking table tests. In the tests, the similitude law suggested by lai was applied to determine the length and the time scaling factors. Also, the steady state concept was used in determining the density of model backfill soil, which is a key factor in simulating the development of excess pore pressure during shaking. The similitude law was verified by checking whether three different sizes of quay walls show the identical behavior or not. The similar responses of acceleration, excess pore pressure and horizontal displacement of walls were obtained far the small and large models. However, the medium model showed larger responses than those of the small and large models because of the resonance between the frequency of input acceleration and the natural frequency of the wall system. In addition, the vertical displacement and rotational angle of the walls became larger with the increase of model size.

A Study on the Development of Planting Design Method for Creating an Ecological Park -Focus on a Correlation between Visual Preference and Ecological Diversity- (생태공원조성을 위한 식재설계방법의 개발 -시각적 선호도와 생태적 다양성의 상호관련성을 중심으로-)

  • 김귀곤;조동길;차영두;황기현
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.27 no.5
    • /
    • pp.12-24
    • /
    • 2000
  • This study seeks to find an approach tool that allows to consider both ecological and visual aspect in developing an ecological space. Main objective of this study is to develop a planting design method in consideration of correlation between high visual preference and ecological diversity. To this end, an integrated method based on visual design principles and landscape ecological principles was developed first. Then study areas of 20 natural areas and 10 urban areas were selected to survey and analyze visual preference and ecological diversity. The result showed that scale is an element that has the greatest impact on visual preference. In areas with high ecological diversity, scale and connectivity had the biggest impact. In order to have a planting design desirable visually and ecologically based on these factors, it may be divided into following three issues.(1) In oder to increase ecological diversity in areas with strong visual preference, a priority should be given to introduce techniques promoting harmony among dominant species of various scales and other species. At the same time, there should be efforts to secure connectivity. (2) To improve visual preferences in areas with high ecological diversity, close-range, medium-range, and distant landscapes should be ensured by aligning colors and connectivity of various scales with other factors. (3) Also, a target area should be developed into a visually preferred and ecologically sound area by supplementing form and interlocking issues and identifying the spirit of the place. This study offers a way to improve visual preference and promote ecological diversity indeveloping ecological parks for the future. In landscape planning and design, it is important to secure various scales and connectivity as high-priority principles.

  • PDF

Colloidal Engineering for Nano-Bio Fusion Research (Nano-Bio 융합 연구를 위한 콜로이드 공학)

  • Moon, Jun Hyuk;Yi, Gi-Ra;Lee, Sang-Yup;So, Jae-Hyun;Kim, Young-Seok;Yoon, Yeo-Kyun;Cho, Young-Sang;Yang, Seung-Man
    • Korean Chemical Engineering Research
    • /
    • v.46 no.4
    • /
    • pp.647-659
    • /
    • 2008
  • Colloids are a heterogeneous system in which particles of a few nanometers to hundreds micrometers in size are finely dispersed in liquid medium, but show homogeneous properties in macroscopic scale. They have attracted much attention not only as model systems of natural atomic and molecular self-assembled structures but also as novel structural materials of practical applications in a wide range of areas. In particular, recent advances in colloidal science have focused on nano-bio materials and devices which are essential for drug discovery and delivery, diagnostics and biomedical applications. In this review, first we introduce nano-bio colloidal systems and surface modification of colloidal particles which creates various functional groups. Then, various methods of fabrication of colloidal particles using holographic lithography, microfluidics and virus templates are discussed in detail. Finally, various applications of colloids in metal inks, three-dimensional photonic crystals and two-dimensional nanopatterns are also reviewed as representative potential applications.

Effect of Catalyst Type and Reaction Medium on Fischer-Tropsch Synthesis for Production of Hydrocarbon from Syngas (합성가스로부터 탄화수소제조를 위한 피서트롭스 반응에 관한 촉매 종류 및 반응매체의 영향)

  • Kim, Chul-Ung;Jeong, Soon-Yong;Jeong, Kwang-Eun;Koh, Jae-Cheon;Chae, Ho-Jeong;Kim, Tae-Wan;Park, Hyun-Joo;Lee, Sang-Bong;Han, Jeong-Sik;Jeong, Byung-Hun
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2010.11a
    • /
    • pp.658-663
    • /
    • 2010
  • With petroleum reserves dwindling, interest has been increasing worldwide in Fischer-Tropsch synthesis (FT) as a method of producing synthetic liquid fuels and chemicals from coal, natural gas or biomass. In general, FT synthesis is operated through the gas phase fixed-bed reaction system. Recently, there are lots of study in supercritical fluid due to unique characteristics such as the quick diffusion of reactant gas, effective removal of reaction heat, and the in-situ extraction of high molecular weight hydrocarbon, such as wax. In this study, our major aim is to obtain a deeper insight into the effect of the type of support on the reaction performance over a supported cobalt catalyst in a fixed bed reactor.

  • PDF

Knit Design using Trencadis Images They Appeared in Antony Gaudi's Work (안토니 가우디 작품의 트랜카디스 이미지를 응용한 니트디자인)

  • Yoo, Jae-Young;Lee, Youn-Hee
    • The Research Journal of the Costume Culture
    • /
    • v.19 no.4
    • /
    • pp.751-765
    • /
    • 2011
  • The purpose of this study is to apply the Trencadis images in Antony Gaudi's work to a design motive and thus provide a new concept for a knitwear design by combining double-knitted fabrics with patchwork applique, taping, stitching and quilting. This study examines the bibliographic text and precedent research related to Antony Gaudi and his works, and analyzes the historical background and formative and stylistic characteristics of Trencadis as it appeared in Gaudi's architectural works. Also this study also examines the characteristics of knitwear and knitting theory while exploring the formative elements and the combined techniques used in modern knitwear design through fashion magazines, medium images, and online sources. The results are as follows: First, Gaudi's work that applies a Trencadis technique has the characteristic of being creative, organic, and environmentally friendly. And in addition, its colorfulness inspires modern fashion design. Second, computerized knitting has been practiced in various ways and the fabrics knitted by both double-knitting jacquard and computerized knitting machines provide a new direction the creation of knitwear. A computerized knitting machine is especially effective for pictorial expression, and is suitable for showing the natural curve of the human body due to its sophistication. Third, as a result of applying a combined technique to the knitting of various fabrics, a combined or fusion design, which is a recent megatrend, is very effective for the design of knitwear while increasing its aesthetic value. Moreover, utilizing techniques that combine patchwork applique, taping, stitching and quilting will create higher value in knitwear. Lastly, with a project of applying combined techniques in the creation of knitwear, designers can become much more creative while taking their imagination much further.

Design Improvement on Wind Turbine Blade of Medium Scale HAWT by Considering IEC 1400-1 Specification (IEC1400-1 규격을 고려한 중형 수평축 풍력발전용 회전날개의 설계개선 연구)

  • 공창덕;정석훈;장병섭;방조혁
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.4 no.3
    • /
    • pp.29-37
    • /
    • 2000
  • Because the previous design procedure for the composite wind turbine blade structure using trial and error method takes long time, a improved design procedure by using the program based on classical laminate theory was proposed to reduce the inefficient element. According to the improved design procedure, limitation of strains, stresses and displacements specified by international standard specification IEC1400-1 for the composite wind turbine blade were applied to sizing the structural configuration by using the rule of mixture and the principal stress design technique with a simplified turbine blade. Structural safety for strength and buckling stability was confirmed by the developed analysis program based on the laminate theory to minimize the design procedure. After modifying the preliminary design result with additional structural components such as skin, foam sandwich and mounting joints, stresses, strains, displacements, natural frequency, buckling load and fatigue life were analyzed by the finite element method. Finally these results were confirmed by comparing with IEC1400-1 specification.

  • PDF

Magnetotelluric modeling considering vertical transversely isotropic electrical anisotropy (수직 횡등방성 전기적 이방성을 고려한 자기지전류탐사 모델링)

  • Kim, Bitnarae;Nam, Myung Jin
    • Geophysics and Geophysical Exploration
    • /
    • v.18 no.4
    • /
    • pp.232-240
    • /
    • 2015
  • Magnetotelluric (MT) survey investigates electrical structure of subsurface by measuring natural electromagnetic fields on the earth surface. For the accurate interpretation of MT data, the precise three-dimensional (3-D) modeling algorithm is prerequisite. Since MT responses are affected by electrical anisotropy of medium, the modeling algorithm has to incorporate the electrical anisotropy especially when analyzing time-lapse MT data sets, for monitoring engineered geothermal system (EGS) reservoir, because changes in different-vintage MT-data sets are small. This study developed a MT modeling algorithm for the simulation MT responses in the presence of electrical anisotropy by improving a pre-existing staggered-grid finite-difference MT modeling algorithm. After verifying the developed algorithm, we analyzed the effect of vertical transversely isotropic (VTI) anisotropy on MT responses. In addition, we are planning to extend the applicability of the developed algorithm which can simulate not only the horizontal transversely isotropic (HTI) anisotropy, but also the tiled transversely isotropic (TTI) anisotropy.