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Histopathological studies on the influence of mast cell in the growth of rat mammary carcinoma 3. Effect of xylazine on the course of DMBA-induced rat mammary carcinoma (Rat mammary carcinoma의 발육(發育)에 있어서 비만세포(肥滿細胞)의 영향(影響)에 관한 병리조직학적(病理組織學的) 연구(硏究) 3. 종양발육(腫瘍發育)에 미치는 xylazine의 효과(效果))

  • Kim, Tae-hwan;Lee, Cha-soo
    • Korean Journal of Veterinary Research
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    • v.31 no.3
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    • pp.343-353
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    • 1991
  • In order to investigate the histopathological, mechanism of Rompun-induced shock, the development of mammary carcinoma, the numerical changes and the morphological findings of the mast cells appeared in the carcinoma were microscopically observed in the rat treated with DMBA and each chemical of compound 48/80 and Rompun. Also mast cell degranulation induced by Rompun was observed with electron microscope. The results observed were summarized as follows: Tumor appeared in 100% of the animals. Tumors grew more rapidly to $10{\times}10mm$ in rats depleted of mast cells ($37.7{\pm}4.2$ days) than was observed in the control group ($42.5{\pm}4.7$ days) (p<0.005). The mean number of tumors per rat was $2.8{\pm}1.3$ in the compound 48/80- treated group in contrast to $3.4{\pm}1.3$ in the control group. No significant difference was apparent in the tumor induction time of Rompun treated group compared with the compound 48/80-treated group, but the tumor measuring at least $10{\times}10mm$ appeared more quickly in the Rompun treated group than in the control group (p<0.005). The numbers of mast cells in the control group were inclined to increase significantly according to the mammary tumor development (p<0.005). In contrast, the mast cells were fewer significantly in the compound 48/80-treated group and Rompun-treated group than in the control group (p<0.005). The numbers of mast cells in the compound 48/80-treated group and Rompun-treated group were inclined to reduce significantly according to the stages of the mammary carcinoma growth in contrast to the control group respectively. The ultrastructural morphologies of mast cells at 30 minutes after Rompun injection were appeared many normal granules in the cytoplasm, but many normal and degranulated granules were scattered along the cell membrane. And at 1 hour after Rompun injection mast cell granules were disappeared nearly or rarely seen. many long cytoplasmic projections were folded back to adhere to their own surface membrane. and mast cells resulted in a reduced size of these cells. Otherwise. compound 48/80 caused extensive degranulation of mast cells by disrupting cell membrane. but mast cell degranulation by Rompun was observed exocytosis of granules through a channel. From the above results. it is concluded that the Rompun may give rise to the dealth of animals as a shock caused by mast cell degranulation.

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Lower the Detection Limits of Accelerator Mass Spectrometry

  • John A., Eliades;Song, Jong-Han;Kim, Jun-Gon;Kim, Jae-Yeol;O, Jong-Ju;Kim, Jong-Chan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.243-244
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    • 2013
  • Over the past 15 years, several groups have incorporated radio-frequency quadrupole (RFQ) based instruments before the accelerator in accelerator mass spectrometry (AMS) systems for ion-gas interactions at low kinetic energy (<40 eV). Most AMS systems arebased on a tandem accelerator, which requires negative ions at injection. Typically, AMS sensitivity abundance ratios for radioactive-to-stable isotope are limited to Xr/Xs >10^-15, and the range of isotopes that can be analyzed is limited because of theneed to produce rather large negative ion beams and the presence of atomic isobaric interferences after stripping. The potential of using low-kinetic energy ion-gas interactions for isobar suppression before the accelerator has been demonstrated for several negative ion isobar systems with a prototype RFQ system incorporated into the AMS system at IsoTrace Laboratory, Canada (Ontario, Toronto). Requisite for any such RFQ system applied to very rare isotope analysis is large transmission of the analyte ion. This requires proper phase-space matching between the RFQ acceptance and the ion beam phase space (e.g. 35 keV, ${\varphi}3mm$, +-35 mrad), and the ability to control the average ion energy during interactions with the gas. A segmented RFQ instrument is currently being designed at Korea Institute for Science and Technology (한국과학기술연구원, KIST). It will consist of: a) an initial static voltage electrode deceleration region, to lower the ion energy from 35 keV down to <40 eV at injection into the first RFQ segment; b) the segmented quadrupole ion-gas interaction region; c) a static voltage electrode re-acceleration region for ion injection into a tandem accelerator. Design considerations and modeling will be discussed. This system should greatly lower the detection limits of the 6 MV AMS system currently being commissioned at KIST. As an example, current detection sensitivity of 41Ca/Ca is limited to the order of 10^-15 while the 41Ca/Ca abundance in modern samples is typically 41Ca/Ca~10^-14 - 10^-15. The major atomic isobaric interference in AMS is 41K. Proof-of-principal work at IsoTrace Lab. has demonstrated that a properly designed system can achieve a relative suppression of KF3-/41CaF3- >4 orders of magnitude while maintaining very high transmission of the 41CaF3- ion. This would lower the 41Ca detection limits of the KIST AMS system to at least 41Ca/Ca~10^-19. As Ca is found in bones and shells, this would potentially allow direct dating of valuable anthropological archives and archives relevant to our understanding of the most pronounced climate change events over the past million years that cannot be directly dated with the presently accessible isotopes.

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Modeling Three-dimensional Free Surface Flow around Thin Wall Incorporation Hydrodynamic Pressure on δ-coordinate (δ-좌표계에서 동수압 계산 수중벽체 인근흐름 수치모형실험)

  • Kim, Hyo-Seob;Yoo, Ho-Jun;Jin, Jae-Yul;Jang, Chang-Hwan;Lee, Jung-Su;Baek, Seung-Won
    • Journal of Wetlands Research
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    • v.16 no.3
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    • pp.327-336
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    • 2014
  • Submerged thin walls are extreme case of submerged rectangular blocks, and could be used for many purposes in rivers or coastal zones, e.g. to tsunami. To understand flow characteristics including flow and pressure fields around a specific submerged thin wall a numerical model was applied which includes computation of hydrodynamic pressure on ${\sigma}$-coordinate. ${\sigma}$-coordinate has strong merits for simulation of subcritical flow over mild-sloped beds. On the other hand ${\sigma}$-coordinate is quite poor to treat sharp structures on the bed. There have been a few trials to incorporate dynamic pressure in ${\sigma}$-coordinate by some researchers. One of the previous approaches includes process of sloving the Poisson equation. However, the above method includes many high-order terms, and requires long cpu for simulation. Another method SOLA was developed by Hirt et al. for computation of dynamic pressure, but it was valid for straight grid system only. Previous SOLA was modified for ${\sigma}$-coordinate for the present purpose and was adopted in a model system, CST3D. Computed flow field shows reasonable behaviour including vorticity is much stronger than the upstream and downstream of the structure. The model was verified to laboratory experiments at a 2DV flume. Time-average flow vectors were measured by using one-dimensional electro-magnetic velocimeter. Computed flow field agrees well with the measured flow field within 10 % error from the speed point of view at 5 profiles. It is thought that the modified SOLA scheme is useful for ${\sigma}$-coordinate system.

A Study on Medical Laws and External Evaluation Criteria with Reference to the Essential Forms consisting Medical Records and to the Items for Each Medical Record (의료기관 종별 의무기록 중요서식 항목별 작성 실태 및 의무기록 완결점검표 분석)

  • Seo, Sun Won;Kim, Kwang Hwan;Hwang, Yong-Hwa;Kang, Sunny;Kang, Jin Kyung;Cho, Woo Hyun;Hong, Joon Hyun;Pu, Yoo Kyung;Rhee, Hyun Sill
    • Quality Improvement in Health Care
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    • v.9 no.2
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    • pp.176-197
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    • 2002
  • Backgound : This study is to suggest the standardized format of the clinical sheets and the standardized items of every clinical sheet. The standardization of the medical records will increase the faithfullnes of the contents in them and it will contribute to construct the good health information system. Method : From Jan. 1st. 2001 to March 31st 2001, we gathered as many paper clinical sheets as possible by every class of institutions to review the faithfulness of the clinical contents in them. Clinical sheets of 9 tertiary care hospitals, 6 general hospitals and 56 clinics were gathered. Two experienced medical record administrators reviewed them. The review focus was to check whether the items recommend by the hospital standardization review criteria and hospital service evaluation organization were appeared in the clinical sheets and whether the contents of every item were written. Results : Tertiary care hospitals; In case of administrative data, the contents were filled well if the items were fixed. The clinical data like C.C, history,physical examiniation were filled well, but if the items were not fixed, some items were omitted. The result is that more items are to be filled if they are fixed. General hospitals Administrative data were filled more than 50%. Final diagnosis was filled about 66.7%.But other clinical data were not filled well and not many clinical related items were appeared in the sheets.In the legal point of view, the reason for visiting hosptals or the right diagnosis, patient condition at discharge could not be confirmed well.In surgery cases, surgical procedures could not be confirmed well as many surgical related information(surgery time, fluids and blood, number of sponges, biopsy, etc) were omitted. Clinics More than 70% administrative data were filled and fixed as items. Among the clinical related data, laboratory result was the most credible data. But without the right diagnosis, drug orders were given and doctors' written signatures were not appeared over 96.4%. So the clinical sheets cannot be used as a legal document. Conculusion : There was a tendency that the contents were filled well if the items were fixed in the documents, We also suggest a clinical check list to review the completeness and faithfulness of the clinical sheets. If many hospitals use the suggested clincal check list and if they make the necessary items fixed in the clinical sheets, the quality of the medical record will increase dramatically.

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Fishery Resources off Youngkwang 1. Species Composition of Catch by a Stow Net (서해 영광 연안 수산자원 I. 주목망 어획자원의 종조성)

  • HWANG Sun Do;IM Yang Jae;KIM Yong Cheol;CHA Hyung Kee;CHOI Seung Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.5
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    • pp.727-738
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    • 1998
  • Seasonal species composition of fishery resources was determined using samples collected by a stow net from April 1995 through January 1996 at 9 stations off Youngkwang. Catch data obtained from a set net using strong tidal current could be used for a quantitative analysis of dominant species. Of the 98 species identified, assemblages were consisted of $52.0\%$ in fishes, $44.6\%$ in shrimps, $2.0\%$ in cephalopods, $1.4\%$ in crabs and <$0.1\%$ in gastropods. Thryssa kammalensis, Crangon hakodatei, Metapenaeus joynezi and Johnius grypotus predominated in abundance, consisting of $68\%$ in the number of individuals, The abundance and species composition fluctuated seasonally, and species could be distinguished by life history pattern with seasons. Seasonal variation in species composition was greater than the spatial variation in a sampling period, As the fine sediment was predominated in the study area, the species composition were significantly different from those of other coastal waters of West Sea, Korea.

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Temperature and Light Responses on the Growth and Maturation of Gametophytes of Undaria pinnatifida (Harvey) Suringar in Korea (한국산 미역 배우체의 생장과 성숙에 대한 온도 및 광반응)

  • KIM Young Sik;NAM Ki Wan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.3
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    • pp.505-510
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    • 1997
  • Temperature and light responses on the growth and maturation of gametophytes of Undaria pinnatifida were studied in laboratory culture. The effect of the environmental factors on formation of young sporophyte of U. pinnatifida was also examined in the same culture system. Maximum growth and rapid maturation of the gametophytes were observed at $12:12LD,\;17^{\circ}C$ and 60{\mu}mol\;m^{-2}s^{-1}. However, they survived in a wide range of the examined temperature, light intensity and photoperiod. Particularly they survived under continuous dark condition (0:24LD) until 210 days without any growth and maturation, but died within $10\~40$ days at $30^{\circ}C$. This suggests that optimum rendition for conservation of Undaria gametophytes is under continuous dark photoperiod at $17\~25^{\circ}C$.

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Sedimentological and Hydromechanical Characteristics of Bed Deposits for the Cultivation of Manila clam, Ruditapes philippinarum in Gomso Tidal Flat (곰소만 조간대 바지락 양식장 저질의 퇴적학적 및 수리역학적 특성)

  • CHO Tae-Chin;LEE Sang-Bae;KIM Suck-Yun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.3
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    • pp.245-253
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    • 2001
  • To investigate the effects of hydromechanical and textural characteristics of sediment deposits on the cultivation of Manila clam, Ruditapes philippinarum surface and sub-surface core sediments were collected seasonally in Gomso tidal flat. Grain size distribution were analyzed to investigate the annual variation of sediment texture. In winter unimodal distribution of grain size with the peak at $5\phi$ is dominant However, during the summer sediment texture become a little bit coarser and grain size distribution shows the peaks at $4\~5 \phi$. Optimum sediment texture for the cultivation of manila clam, R. philippinarum was found to be sandy silt in which mean Brain size was between 4 and $5 \phi$ with the sand content less than $50\%$ and clay content of $5\~10\%$. Mechanical and hydrological characteristics of sediment deposits were also studied in the laboratory and the results were applied to the numerical simulation for the behavior of surface sediment subjected to the cyclic loading from sea-water level change. Results of numerical simulation illustrate that the permeability of sediment had to be maintained in the range of $10^{-11}\sim10^{-12}m^2$ to ensure the proper sedimentological environment for the cultivation of manila clam, R. philippinarum. The deposits of virtually impermeable mud layer, with the threshold thickness of 4 cm, would be very hazardous to clam habitat.

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Adsorption and Removal Mechanism of Dissolved Inorganic Nutrients in Seawater by Yellow Loess (황토살포에 의한 해수중 영양염류의 흡착제거기구)

  • Kim Pyoung Joong;Heo Seung;Yun Seong Jong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.2
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    • pp.146-154
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    • 2002
  • To assess the adsorption and removal mechanism of dissolved inorganic nutrients in seawater by scattering yellow loess, a laboratory experiment was conducted for the change of nutrient concentration in seawater during the course of time depending on particle size and scattered concentration of the yellow loess. Twenty four hours after the addition of yellow loess in the size range of 0 $\mu$m to 500 $\mu$m in seawater, the removal rate of dissolved inorganic phosphorus (DIP) was increased with increasing amount of yellow loess. There was little difference among the removal rates depending on the size of yellow loess. On average, $26\%$ of dissolved inorganic silicate was reduced for the same period. No greate difference among the removal rate depending on both size and amount of yellow loess was found. Our results suggested that the removal mechanism of DU seemed to be associated with mostly the chemical bond with iron. More than $99\%$ of initial DU concentration was likely to be removed by this mechanism. In the case of inorganic dissolved silicate, the removal mechanism was likely to be attributed to a cation exchange between the yellow loess and seawater.

THE GROWTH OF FOOD ORGANISMS FOR THE MASS PRODUCTION OF MOLLUSCAN SEEDLINGS 1. Phaeodactylum, Platymonas and Chlorella (패류 종묘의 대 생산시에 필요한 먹이 생물의 배양에 관한 연구 1. Phaeodactylum, Platymonas 및 Chlorella)

  • Yoo Sung Kyoo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.3 no.1
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    • pp.1-6
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    • 1970
  • A series of experiments have been made on the mass culture of Phaeodactylum tricornutum, Platymonas sp. and Chlorella sp. in the laboratory. The shortest lag phase was found In the culture of Ph. tricornutum followed by Platymonas sp. and Chlorella sp. As compared to the aeration culture, the stagnant culture, in general, showed long duration of the lag phase, short period of the exponential phase and extremely small daily increment. The relative growth constants of Ph. tricornutum, Chlorella sp. and Platymonas sp. were $0.302{\pm}0.028$, $0.226{\pm}0.013$, and $0.151{\pm}0.008$, respectively The maximum daily increment of the three species and then daily ages are as follows: Ph. tricornutum Maximum daily increment : 47.5, Daily age : 10, Platymonas sp. Maximum daily increment : 5.6, Daily age : 14, Chlorella sp. Maximum daily increment : 21.1, Daily age : 14 Comparing the packed cell volume with a certain number of cells, the largest value was found in the population of Ph. tricornutum followed by Platymenas sp. and Chlorella sp. A straight line relationship exists between the two values, and the magnitude of the relationship coincides well with the size of the cells. The culture of Ph. tricornutum was proved satisfactory for feeding the larvae of bivalves at about 12 days after innoculation and both of Platymenas sp. and Chlorella sp. were about 16 days respectively.

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STUDIES ON THE SHELLFISH PROCESSING 1. Purification of the Surf Clam Mactra sulcataria REEVE for the Remove of Sand (패류 가공에 관한 연구 1. 개량조개 Mactra Sulcataria REEVE의 토사 배출에 대하여)

  • LEE Eung-Ho;PYEUN Jae-Hyeung;HUR Jong-Wha
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.3 no.1
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    • pp.27-32
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    • 1970
  • A study on the purification of the surf clam Mactra Sulcataria REEVE for the remove of sand and fecal piles was conducted in the laboratory. The sand was mostly distributed around the inhalent and exhalent siphon, mantle and gill, and were also distributed in the digestive tract including the mid-gut gland. The sand particles in the digestive tract were extremely small and their sizes were about $180\times10\mu\;to\;550\times200\mu$. It could be seen that there was little, if any, difference in the rate of sand removal when either the hanging Purification method was used or the method of laying the surf clams in thick or thin layers on the bottom of the experimental vessel was used. The surf clam removed about $50\%$ of its sand during the first hour of purification. The weight of the removed sand and fecal piles on a dry basis reached a constant value after 22 to 26 hours of purification. After 42 hours of Purification, no sand could be seen in the fecal piles. The surf clam removed the sand in its body more rapidly when it was in sea water with the pH of 8.75 than when it was in natural sea water. Also high temperature had a much greater depressing effect upon the removal of sand In the surf clam than did natural sea water. Also low salinity had greater accelerating effect upon the removal of sand in the body than did natural sea water. However the surf clam died when the salinity was $8.19\%_{\circ}$.

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