• Title/Summary/Keyword: 전달현상

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A Knowledge-based Approach for the Estimation of Effective Sampling Station Frequencies in Benthic Ecological Assessments (지식기반적 방법을 활용한 저서생태계 평가의 유효 조사정점 개수 산정)

  • Yoo, Jae-Won;Kim, Chang-Soo;Jung, Hoe-In;Lee, Yong-Woo;Lee, Man-Woo;Lee, Chang-Gun;Jin, Sung-Ju;Maeng, Jun-Ho;Hong, Jae-Sang
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.16 no.3
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    • pp.147-154
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    • 2011
  • Decision making in Environmental Impact Assessment (EIA) and Consultation on the Coastal Area Utilization (CCAU) is footing on the survey reports, thus requires concrete and accurate information on the natural habitats. In spite of the importance of reporting the ecological quality and status of habitats, the accumulated knowledge and recent techniques in ecology such as the use of investigated cases and indicators/indices have not been utilized in evaluation processes. Even the EIA report does not contain sufficient information required in a decision making process for conservation and development. In addition, for CCAU, sampling efforts were so limited that only two or a few stations were set in most study cases. This hampers transferring key ecological information to both specialist review and decision making processes. Hence, setting the effective number of sampling stations can be said as a prior step for better assessment. We introduced a few statistical techniques to determine the number of sampling stations in macrobenthos surveys. However, the application of the techniques requires a preliminary study that cannot be performed under the current assessment frame. An analysis of the spatial configuration of sampling stations from 19 previous studies was carried out as an alternative approach, based on the assumption that those configurations reported in scientific journal contribute to successful understanding of the ecological phenomena. The distance between stations and number of sampling stations in a $4{\times}4$ km unit area were calculated, and the medians of each parameter were 2.3 km, and 3, respectively. For each study, approximated survey area (ASA, $km^2$) was obtained by using the number of sampling stations in a unit area (NSSU) and total number of sampling stations (TNSS). To predict either appropriate ASA or NSSU/TNSS, we found and suggested statistically significant functional relationship among ASA, survey purpose and NSSU. This empirical approach will contribute to increasing sampling effort in a field survey and communicating with reasonable data and information in EIA and CCAU.

Alteration of Phospholipase D Activity in the Rat Tissues by Irradiation (방사선 조사에 의한 쥐 조직의 포스포리파제 D의 활성 변화)

  • Choi Myung Sun;Cho Yang Ja;Choi Myung-Un
    • Radiation Oncology Journal
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    • v.15 no.3
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    • pp.197-206
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    • 1997
  • Purpose : Phospholipase D (PLD) catalyzes the hydrolysis of phosphatidylcholine to phosphatidic acid (PA) and choline. Recently, PLD has been drawing much attentions and considered to be associated with cancer Process since it is involved in cellular signal transduction. In this experiment, oleate-PLD activities were measured in various tissues of the living rats after whole body irradiation. Materials and Methods : The reaction mixture for the PLD assay contained $0.1\;\muCi\;1,2-di[1-^{14}C]palmitoyl$ phosphatidylcholine 0.5mM phosphatidylcholine, 5mM sodium oleate, $0.2\%$ taurodeoxycholate, 50mM HEPES buffer(pH 6.5), 10mM $CaCl_2$, and 25mM KF. phosphatidic acid, the reaction product, was separated by TLC and its radioactivity was measured with a scintillation counter. The whole body irradiation was given to the female Wistar rats via Cobalt 60 Teletherapy with field size of 10cmx loom and an exposure of 2.7Gy per minute to the total doses of 10Gy and 25Gy. Results : Among the tissues examined, PLD activity in lung was the highest one and was followed by kidney, skeletal muscle, brain, spleen, bone marrow, thymus, and liver. Upon irradiation, alteration of PLD activity was observed in thymus, spleen, lung, and bone marrow. Especially PLD activities of the spleen and thymus revealed the highest sensitivity toward $\gamma-rar$ with more than two times amplification in their activities In contrast, the PLD activity of bone marrow appears to be reduced to nearly $30\%$. Irradiation effect was hardly detected in liver which showed the lowest PLD activity. Conclusion : The PLD activities affected most sensitively by the whole-body irradiation seem to be associated with organs involved in immunity and hematopoiesis. This observation s1ron91y indicates that the PLD is closely related to the physiological function of these organs, Furthermore, radiation stress could offer an important means to explore the phenomena covering from cell Proliferation to cell death on these organs.

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STS and the Innovation of Sociology: Focusing on Actor-Network Theory (STS(과학기술학)와 사회학의 혁신: 행위자-연결망이론(ANT)을 중심으로)

  • Kim Hwan-Suk
    • Journal of Science and Technology Studies
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    • v.1 no.1 s.1
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    • pp.201-234
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    • 2001
  • Sociology(or social science in general) is often diagnosed as in the state of 'crisis' after the collapse of socialism and the erosion of national societies because of rapid globalization. This paper introduces some recent work within science and technology studies(STS) and discusses its potentials to reinvigorate sociology. Although sociologists have rarely regarded STS as contributing to 'mainstream' issues in sociology, an increasing number of STS writers and sociologists have recently started to notice such possibilities. One main reason of this recent change is that STS is no longer merely concerned to convey substantive findings about science and technology, but instead attempts to reconstruct key notions of sociology such as 'social', 'society' and 'agency'. It is in this respect that the discussion below aims to introduce, discuss, and assess the potential contribution of some recent work of STS to sociology. In particular, it is 'actor-network theory'(ANT) that explicitly attempts to examine and suggest the ways in which STS ran help innovate sociology. One major characteristics of ANT is to impute 'agency' to things(nonhumans) unlike traditional sociology. ANT argues that if sociology studies heterogeneous relationships between humans and nonhumans instead of human relations only, it can become once again a vigorous discipline which is able to provide alternative worlds central to the basis of sociology. So this paper focuses on, not the diverse approaches of STS, the characteristics of ANT and its potential contribution to sociology. The author concludes that ANT can not only rejuvenate sociology by implicating new forms of alternative worlds but also open the possibility to contribute to the democratic reformulation of human-nonhuman relationships.

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Optimization of Biotransformation Process for Sodium Gluconate Production by Aspergillus niger (Aspergillus niger를 이용한 글루콘산 나트륨 생산 생변환 공정의 최적화)

  • 박부수;조병관;이상윤;임승환;김동일;김병기
    • KSBB Journal
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    • v.14 no.3
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    • pp.309-314
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    • 1999
  • In order to produce high concentration of sodium gluconate, optimization of the fermentation conditions, such as glucose concentration, inoculum size, dissolved oxygen concentration and glucose feeding method, was examined. When the glucose concentration was maintained in the range of 30∼50 g/L during the batch fermentation, glucose conversion yield and productivity were 92.2% and 6.0 g/L/hr, respectively. In the case of the low concentration below 30 g/L, the yield decreased by about 25%. As the inoculum size increased above 20%(w/v), lag phase was shortened but the productivity decreased. The dissolved oxygen level of 60∼70% was shown to be the threshold point for 75% of increase in the productivity of sodium gluconate. Finally, optimal glucose feeding rate was determined using various feeding methods such as exponential feeding, feeding based on the average glucose consumption rate and was determined using various feeding methods such as exponential feeding, feeding based on the average glucose consumption rate and on the oxygen uptake rate and etc. Our result shows that glucose feeding, based on the oxygen uptake rate is a very simple, efficient and robust method, especially when oxygen is consumed as a substrate for the bioconversion. Using the above glucose feeding strategy under the optimized condition, 255 g/L of sodium gluconate concentration, 12 g/L/hr of productivity and 95% of glucose conversion yield were achieved with A. niger ACM53.

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Heat Budget Analysis of Light Thin Layer Green Roof Planted with Zoysia japonica (한국잔디식재 경량박층형 옥상녹화의 열수지 해석)

  • Kim, Se-Chang;Lee, Hyun-Jeong;Park, Bong-Ju
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.6
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    • pp.190-197
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    • 2012
  • The purpose of this study was to evaluate thermal environment and heat budget of light thin layer green roof through an experiment in order to quantify its heat budget. Two concrete model boxes($1.2m(W){\times}1.2m(D){\times}1.0m(H)$) were constructed: One experiment box with Zoysia japonica planted on substrate depth of 10cm and one control box without any plant. Between June 6th and 7th, 2012, outside climatic conditions(air temperature, relative humidity, wind direction, wind speed), evapotranspiration, surface and ceiling temperature, heat flux, and heat budget of the boxes were measured. Daily maximum temperature of those two days was $29.4^{\circ}C$ and $30^{\circ}C$, and daily evapotranspiration was $2,686.1g/m^2$ and $3,312.8g/m^2$, respectively. It was found that evapotranspiration increased as the quantity of solar radiation increased. A surface and ceiling temperature of those two boxes was compared when outside air temperature was the greatest. and control box showed a greater temperature in both cases. Thus it was found that green roof was effective in reducing temperature. As results of heat budget analysis, heat budget of a green roof showed a greater proportion of net radiation and latent heat while heat budget of the control box showed a greater proportion of sensible heat and conduction heat. The significance of this study was to analyze heat budget of green roof temperature reduction. As substrate depth and types, species and seasonal changes may have influences on temperature reduction of green roof, further study is necessary.

Effects of Single and Repeated Electroconvulsive Shock on the Acetylcholine and Polyamine Contents in Temporal Cortex and Decorticated Cerebrum of Mice (경련성 전기충격에 의하여 나타나는 측뇌-피질과 피질을 제외한 대뇌의 Acetylcholine및 Polyamine 함량-변동에 관한 연구)

  • Choi, Sang-Hyun;Lee, Hak-Hee;Park, Chung-San;Chun, Boe-Gwun;Chun, Yeon-Sook
    • The Korean Journal of Pharmacology
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    • v.27 no.1
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    • pp.13-20
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    • 1991
  • There are some rather conflicting reports correlating ECS-induced changes of brain acetylcholine, and recently, Zawia and Bondy(1990) proposed the biological role of polyamine system in the long-term adaptive responses of brain to electrical stimulation. This study was undertaken to evaluate the effects of a single or repeated ECS(10mA, 100cps, 1sec; 5 ECS spread out over 9 days) on the brain acetylcholine(ACh) and polyamine contents of male mice. The ACh contents of temporal cortex(TCx) and decorticated cerebrum(dc-CB) were markedly increased by 79.9% and 49.4%, respectively, 10 and 30 min after ECS, and the increases were significantly attenuated with repeated 5 ECS, particularly in dc-CB. The putrescine concentrations of both TCx and dc-CB were little different and not affected by 1 ECS or 5 ECS. But the spermidine(Sd) concentration was higher in dc-CB and spermine(Sm) higher in TCx. While they were moderately decreased after 1 ECS, and their decreases were accentuated after 5 ECS, particularly in dc-CB.Sm(30mg/kg, i.p. inject. 30min before ECS) did not affect the ECS-induced increase of ACh content. Thease results suggest that both of brain ACh and polyamine may be implicated with the long-term adaptive responses to electrical stimulation

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Study about porous of Korean traditional pottery (한국전통옹기의 통기성에 관한연구)

  • Kim, Seok-Ho
    • Journal of Science of Art and Design
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    • v.9
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    • pp.5-24
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    • 2006
  • Human hunted and picked to survive and a vessel was made naturally to store something being hunted and picket, which was a great invention. In modern times, society changed and development of science gave us convenience in making a vessel and various kinds of store instruments which was made of pure natural material, of new stuff, such as plastic and iron. but human became to be inclined to regress into nature because of problems of environment. We can say that the representative trend is well-being, after all this is a symptom to return to life being persued by predecessors before the science civilization was developed. Ancestors have lived with nature, adapted themselves to it. For examples they have built the house which became to be a part of nature and just like it, and studied a method of storing food to eat for four seasons, then displayed a storagehouse and storage containers everywhere of the house. Now Korean has the custody of kimchi in refrigerator at every house, but our forefathers controled a timing to eat food with studying a method of storage to put to use nature. With hot wind of well-being, Korean food is becoming to be globalized, according to this, concern about the wisdom of progenitors is growing more and more. It's an example that the world shows concern seriously about the pottery, which have stored kimchi for a long time fleshly, in globalization of kimchi. This study have three purposes, the first. checking documents about the development history of pottery which is a kind of ceramic, and then the second, through an scientific experiment, with studying characteristic of pottery being built by the wisdom of ancestors, informing the merit of pottery and necessity to the world, and futhermore, the third, working up the development of close environmental vessels putting to use the characteristic of pottery.

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Applications of "High Definition Digital Climate Maps" in Restructuring of Korean Agriculture (한국농업의 구조조정과 전자기후도의 역할)

  • Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.9 no.1
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    • pp.1-16
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    • 2007
  • The use of information on natural resources is indispensable to most agricultural activities to avoid disasters, to improve input efficiency, and to increase lam income. Most information is prepared and managed at a spatial scale called the "Hydrologic Unit" (HU), which means watershed or small river basin, because virtually every environmental problem can be handled best within a single HU. South Korea consists of 840 such watersheds and, while other watershed-specific information is routinely managed by government organizations, there are none responsible for agricultural weather and climate. A joint research team of Kyung Hee University and the Agriculture, forestry and Fisheries Information Service has begun a 4-year project funded by the Ministry of Agriculture and forestry to establish a watershed-specific agricultural weather information service based on "high definition" digital climate maps (HD-DCMs) utilizing the state of the art geospatial climatological technology. For example, a daily minimum temperature model simulating the thermodynamic nature of cold air with the aid of raster GIS and microwave temperature profiling will quantify effects of cold air drainage on local temperature. By using these techniques and 30-year (1971-2000) synoptic observations, gridded climate data including temperature, solar irradiance, and precipitation will be prepared for each watershed at a 30m spacing. Together with the climatological normals, there will be 3-hourly near-real time meterological mapping using the Korea Meteorological Administration's digital forecasting products which are prepared at a 5 km by 5 km resolution. Resulting HD-DCM database and operational technology will be transferred to local governments, and they will be responsible for routine operations and applications in their region. This paper describes the project in detail and demonstrates some of the interim results.

Geochemical Exploration Technics in the Pungchon Limestone Area (풍촌 석회암지대 탐사에 적용될 새 지화학탐사법 연구)

  • Moon, Kun Joo
    • Economic and Environmental Geology
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    • v.23 no.4
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    • pp.369-381
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    • 1990
  • Most of significant ore deposits in South Korea such as the Sangdong W - Mo, the Yeonhwa Pb-Zn and the Geodo Cu-Fe skarn ore deposits occur at the southern limb of the Hambaeg syncline in the Taebaeg Basin. The mineralization took place in the interbedded limestone of the Myobong Formation and the Pungchon limestone of the Great Limestone Group of the Cambrian age, generally striking E-W and dipping 25-30 degrees north. There are no outcrops of the skarn-type orebody at the northern limb of the syncline. In order to find a clue of a possible hidden orebody localized at the limestones in the northern limb, a lithogeochemical exploration by using carbon isotope and some elements such as Si, Ca, Fe and Al at the Sangdong Mine area has been attempted as for a modelling study. For this study, 45 samples from the Pungchon limestone which do not show any megascopic indication of mineralization have been taken in both the mineralized zone and the unminerallized zone at the Sangdong Mine area. Analytical data show that there are big differences in the contents of CaO and $Al_2O_3$ between the Pungchon limestone of the mineralized zone and that of the unmineralized zone. Carbon isotope data exhibit that ${\delta}^{13}C$ values of the Pungchon limestone in the mineralized zone are highter than those in the unmineralized zone. The difference in the analytical values of CaO, $Al_2O_3$ and the carbon isotope between the mineralized and the unmineralized zones is as follows ; Unminerallized zone Mineralized zone CaO 51.3% 43.5% $Al_2O_3$ 0.6% 2.4% ${\delta}^{13}C$ -0.39 permil -0.56 permil $Fe_2O_3$ 0.9% 1.4% $SiO_2$ 3.0% 2.4% The decrease in the Si content of the Pungchon limestone in the mineralized zone is contrary to the result of the previous study (Moon, 1987). On the basis of identification of the increase in the Al content of the limestone in the mineralized zone, it could be deduced that the decrease in the Si content of the Pungchon limestone might be due to the result of increase in the alteration products mainly occurred along fracture-system such as joint cracks or minor faults and that the phenomena shown by the Si and Al content in the mineralized zone might be derived from the thermal effect of granite extended mineralizing activity to the overlied limestone on the surface. Higher mean values of Fe and Al as well as lower mean values of carbon content and the ${\delta}^{13}C$ than mean values of those in the Pungchon limestone at the northern limb of the Hambaeg Syncline may be applicable in exploration for blind orebodies.

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The Effect of LhGH on Hair Regeneration in C57BL/6CrN Mouse (LhGH가 마우스(C57BL/6CrN)의 모발 재성장에 미치는 영향)

  • Kim, Yong-Ju;Kim, Tae-Keun;Min, Byoung-Hoon;Kim, Soo-Jin
    • Applied Microscopy
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    • v.41 no.1
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    • pp.47-53
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    • 2011
  • Hair is an appendage of skin which protects the body from outer physical and chemical stimuli. Hair is generated from the hair follicle lying on a sunken basal layer of epidermis. Hair cycling, which regenerates hair follicles throughout the life time of the organism. Numerous kinds of factors which exist at the hair follicle have been reported to regulate hair cycling, Human growth hormone secreted from pituitary gland, initially demonstrated to accelerate organ's growth, has been reported to play a role in the biology of organ size determination. We investigated the effect of 6-histidines residues tagged at amino-terminus of human growth hormone using light and electronmicroscopic methods. Human growth hormone encapsulated in nano-liposome (LhGH) was used to find how LhGH affects hair follicle cycling of mouse (C57BL6/CrN). Distilled water as a negative control, 3% Minoxidil as a positive control, and LhGH were applied to mouse for weeks. LhGH increased the number of exposed hairs per given areas ($1mm^2$). This result was also confirmed using a different breed of mice which show natural hair loss in an old age (about 17 months after birth). When LhGH was applied for 3 weeks after natural hair loss, natural hair loss on these mice was prevented, However, the control group mice on which LhGH was not applied showed further hair loss. This result indicates that LhGH may stimulate hair cycling of mouse. In clusion, it is cleat that the LhGH increased the number of hair on mice and help the depilated skin to grow new hair follicles again.