• Title/Summary/Keyword: Capsule shape

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Development of a Wheel Type Locomotive Mechanism Using Micro motor for a Capsule-Type Endoscope (모터를 이용한 바퀴형 체내이동 메커니즘의 개발)

  • Lee, Young-Jae;Kim, Byung-Kyu;Lim, Young-Mo;Park, Jong-Oh;Hong, Yeh-Sun;Kim, Soo-Hyun
    • Proceedings of the KSME Conference
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    • 2001.06b
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    • pp.289-294
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    • 2001
  • The two prototypes of a Wheel Type Locomotive Mechanism Using Micro motor for a Capsule-Type Endoscope are outlined and realized. Basic concept of these mechanisms is to use a rod-shaped wheel, with which these mechanisms can go over the haustral folds inside colon. The actuator of Prototype I is geared dc motor and the actuator for steering is Shape Memory Alloy. Prototype I goes through the whole area of colonoscopy training model. Prototype II can not only go forward and backward, but also be steerable with 2 geared dc motors. Prototype II goes through dead pig colon.

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CFD ANALYSIS FOR THE DRAG OF AN INTERIOR BODY IN A PULSATILE FLOW WITH VARIOUS SHAPE DESIGN (맥동류 내 물체 형상에 따른 항력에 대한 CFD 계산)

  • Hwang, D.Y.;Han, Byeong-Yun;Yu, Seong-Su;Lee, Myeong-Su;Park, H.K.
    • 한국전산유체공학회:학술대회논문집
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    • 2009.11a
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    • pp.38-43
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    • 2009
  • The objective of this study is to get a fundamental data for the shape of a robot which operates in blood vessels. The overall analysis was calculated with a CFD code. The flow was idealized as a pulsatile flow, and first the robot was assumed as a simple capsule model. Then a drag of the body in the flow was calculated, and this process was repeated, varying the shape. To validate all the result, the pulastile velocity simulation was compared with the theoretical data, and the drag of a body was compared with the existing data of the other papers first. Then with the next calculation the guideline for the design of robot shape was presented.

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Relationship Between Computed Tomography Manifestations of Thymic Epithelial Tumors and the WHO Pathological Classification

  • Liu, Guo-Bing;Qu, Yan-Juan;Liao, Mei-Yan;Hu, Hui-Juan;Yang, Gui-Fang;Zhou, Su-Jun
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.11
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    • pp.5581-5585
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    • 2012
  • Objective: To explore the relationship between computed tomography (CT) manifestations of thymoma and its WHO pathological classification. Methods: One hundred and five histopathologically confirmed cases were collected for their pathological and CT characteristics and results were statistically compared between different pathological types of thymoma. Results: Tumor size, shape, necrosis or cystic change, capsule integrity, invasion to the adjacent tissue, lymphadenopathy, and the presence of pleural effusion were significantly different between different pathological types of thymomas (P<0.05). Type B2, B3 tumors and thymic carcinomas were greater in size than other types. More than 50% of type B3 tumors and thymic carcinomas had a tumor size greater than 10 cm. The shape of types A, AB, and B1 tumors were mostly round or oval, whereas 75% of type B3 tumors and 85% of thymic carcinomas were irregular in shape. Necrosis or cystic change occurred in 67% of type B3 thymomas and 57% of thymic carcinomas, respectively. The respective figures for capsule destruction were 83% and 100%. Increases in the degree of malignancy were associated with increases in the incidence of surrounding tissue invasion: 33%, 75%, and 81% in type B2, type B3, and thymic carcinomas, respectively. Pleural effusion occurred in 48% of thymic carcinomas, while calcification was observed mostly in type B thymomas. Conclusions: Different pathological types of thymic epithelial tumors have different CT manifestations. Distinctive CT features of thymomas may reflect their pathological types.

Structures of hemal nodes and hemolymph nodes in sheep (면양의 혈절과 혈림프절의 구조)

  • Park, Cheol-beom;Seong, Je-kyung;Lee, In-se;Lee, Heungshik S.;Lee, Joon-sup;Yoon, Yeo-sung
    • Korean Journal of Veterinary Research
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    • v.41 no.3
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    • pp.281-285
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    • 2001
  • This study was performed to investigate the gross anatomical features and microscopical structures of the hemal nodes and the hemolymph nodes in the sheep. The hemal nodes and hemolymph nodes were observed mainly in periphery of the thoracic and abdominal aortae of the animals. The size of hemal nodes was generally smaller than that of the hemolymph nodes, and the shape of the both organs was spherical or ovoid. The color of the hemal nodes was red, while that of the hemolymph nodes was grary with red bands. The hemal nodes were surrounded by a relatively thick connective tissue capsule and there were extensive subcapsular sinuses distended by a great number of erythrocytes. Although a few number of lymphatic nodules and small areas of diffuse lymphatic tissues were observed in the parenchyma, no typical cortex and medulla were defined in the hemal node. Small numbers of blood vessels were found at the connective tissue capsule but lymph vessel was not observed microscopically in this organ. The hemolymph nodes were covered by a relatively thick connective tissue capsule and there was a hilus in each node. The parenchyma was divided into cortex and medulla. The cortex was composed of a few numbers of lymphatic nodules and some diffuse lymphatic tissues. The medulla comprised medullary sinuses and cords. Afferent and efferent lymph vessels were observed at the periphery of the capsule adn the hilus, respectively. The subcapsular and medullary sinuses were not extensive but filled with small numbers of erythrocytes. The stroma of hemal node and hemolymph node was composed of reticular cells and fibers, and the capsule and trabecula consisted of collagenous fibers with smooth muscle fibers.

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Poly(ε-caprolactone) Microcapsule with Encapsulated Nifedipine Prepared by Magnetic Stirrer

  • Lee, Hyeran;Lee, Deuk Yong;Song, Yo-Seung;Kim, Bae-Yeon
    • Journal of Biomedical Engineering Research
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    • v.40 no.1
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    • pp.7-14
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    • 2019
  • The microencapsulation of nifedipine (NF) with 4 wt% of poly(${\varepsilon}-caprolactone$) (PCL)/polyvinylpyrollidone (PVP) or PCL/polyethylene glycol (PEG) was carried out by solvent evaporation method in oil in water emulsion system to investigate the effect of PVP and PEG addition on drug release behavior of the microcapsules. The PVA (emulsifier) concentration of 1.0 wt% was chosen for the formation of PCL capsule having an average size of $154{\pm}25{\mu}m$ due to nearly spherical shape with a narrow size distribution. As PCL/PVP and PCL/PEG ratios were raised from 10/0 to 6/4, the capsule size increased gradually from $154{\pm}25{\mu}m$ to $236{\pm}32{\mu}m$ and $248{\pm}56{\mu}m$, respectively. The drug release rate of PCL/PVP and PCL/PEG capsules increased dramatically from 0 to 4 h at the beginning and then reached the plateau region from 20 h. As the concentration of PVP or PEG increased, the amount of drug release increased, suggesting that the larger capsule size was attributed to the higher drug content. However, the drug release behavior remained almost constant. The PCL capsules exhibited no evidence of causing cell lysis or toxicity regardless of NF loading, implying that the microcapsules are clinically suitable for use as drug delivery systems.

An updated taxonomy of the family Linderniaceae in Korea

  • Bazarragchaa, Badamtsetseg;Yang, Seungah;Kim, Hyoun Sook;Lee, Sang Jin;Lee, Joongku
    • Korean Journal of Agricultural Science
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    • v.46 no.4
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    • pp.1007-1018
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    • 2019
  • In the present study, according to morphological observations followed by recent circumscriptions, we have classified the Korean taxa of the family Linderniaceae into Scrophulariaceae sensu lato has been considered in several works, though the taxa have remained undefined because identification work was mostly done according to vegetative morphological features, such as the leaf shape, leaf margins, and leaf venation. The taxa of Linderniaceae are mostly considered to be weeds and, for correct identification, it is necessary to clarify their taxonomic characteristics. Morphological studies were carried out using samples collected in the field. Micro-morphological observations of the vegetative and floral parts were also performed using light microscopy (LM) and scanning electron microscopy (SEM). We concluded that important characteristics are reproductive morphologies viz. calyx, stamen structure, capsule shape, calyx ratio with capsule, inflorescence morphology, and seed morphology. As a result, we formulated taxa descriptions and provided a key of the genera of Linderniaceae in Korea. Lindernia crustacea (L.) F. Muell. is transferred to Torenia crustacea (L.) Cham. & Schltdl. Lindernia micrantha D. Don and L. angustifolia (Benth.) Wettstein are a synonym of Vandellia micrantha (D. Don) Eb. Fisch., Schäferh. & Kai Müll. Lindernia attenuata Muhl. and L. dubia var. major (Pursh) Pennell are a synonym of Lindernia dubia (L.). Lindernia verbenifolia (Colsm.) Pennell is a synonym of Bonnaya antipoda Druce. Our study reports the presence of four genera: Bonnaya, Lindernia, Torenia, and Vandellia, comprising six taxa under the family Linderniaceae in Korea.

ADVANCED TEST REACTOR TESTING EXPERIENCE - PAST, PRESENT AND FUTURE

  • Marshall Frances M.
    • Nuclear Engineering and Technology
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    • v.38 no.5
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    • pp.411-416
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    • 2006
  • The Advanced Test Reactor (ATR), at the Idaho National Laboratory (INL), is one of the world's premier test reactors for providing the capability for studying the effects of intense neutron and gamma radiation on reactor materials and fuels. The physical configuration of the ATR, a 4-leaf clover shape, allows the reactor to be operated at different power levels in the comer 'lobes' to allow for different testing conditions for multiple simultaneous experiments. The combination of high flux (maximum thermal neutron fluxes of 1E15 neutrons per square centimeter per second and maximum fast [E>1.0 MeV] neutron fluxes of 5E14 neutrons per square centimeter per second) and large test volumes (up to 122 cm long and 12.7 cm diameter) provide unique testing opportunities. The current experiments in the ATR are for a variety of test sponsors - US government, foreign governments, private researchers, and commercial companies needing neutron irradiation services. There are three basic types of test configurations in the ATR. The simplest configuration is the sealed static capsule, which places the capsule in direct contact with the primary coolant. The next level of experiment complexity is an instrumented lead experiment, which allows for active control of experiment conditions during the irradiation. The most complex experiment is the pressurized water loop, in which the test sample can be subjected to the exact environment of a pressurized water reactor. For future research, some ATR modifications and enhancements are currently planned. This paper provides more details on some of the ATR capabilities, key design features, experiments, and future plans.

Gametogenesis and Reproductive Cycle of the Rock Shell, Reishia (Thais) clavigera (Neogastropoda: Muricidae), on the West Coast of Korea

  • Lee, Ju-Ha
    • Animal cells and systems
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    • v.3 no.4
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    • pp.375-383
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    • 1999
  • Gonadal development, gametogenesis, reproductive cycle, and first sexual maturity of Reishia clavigera were investigated monthly from July 1998 to June 1999 through cytological and histological observations. R. clavigera had separate sexes, and was an internal fertilizer. The ma1e penis was located near the two tentacles. The ovary and testis were composed of a great number of oogenic lobules and spermatogenic tubules, respectively. The size of ripe oocyte ranged from 130 to 140 ${\mu}$m in diameter. The peripheral cytoplasm of the germinal vesicle of the ripe oocyte in many cases were surrounded by smaller yolk granules, while the eccentric cytoplasm was occupied with larger ones. The reproductive cycle of R. clavigera could be classified into five successive stages: early active, late active, ripe, spawning, and recovery. Spawning of females occurred from early July to August when the seawater reached above 24.8$^{\circ}C$. Spawning of males occurred from early June to August in the water above 22.8$^{\circ}C$. Minimum size for sexual maturity of both sexes was above 10.0 mm in shell height. Each egg capsule was a cylinder or spindle in shape, 4-6 mm in length and 1-2 mm in width. Colors of newly spawned egg capsules showed yellowish white or pale yellow, while those with veliger larvae showed pale black, and released larvae or dead egg capsules showed black violet. The fecundity in an egg capsule ranged from 70 to 91 eggs (mean=80.28 eggs).

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Measurement of Melting Temperatures of $UO_2,\;(U,Gd)O_2\;and\;(U,Er)O_2$ Fuels

  • Kang Ki Won;Yang Jae Ho;Kim Keon Sik;Kim Jong Hun;Lee Young Woo;Song Kun Woo
    • Nuclear Engineering and Technology
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    • v.36 no.1
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    • pp.104-111
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    • 2004
  • The melting temperatures of $UO_2,\;UO_2-6wt\%Gd_{2}O_3,\;UO_2-12wt\%Gd_{2}O_3,\;UO_2-2wt\%Er_{2}O_3,\;and\;UO_2-4wt\%Er_{2}O_3$ fuels were measured. Fuel materials were loaded in a tungsten capsule of which shape met the black body condition. The melting temperature was measured by the thermal arrest method during heating of the capsule in an induction furnace. The measured melting temperature of $UO_2$ fuel was $2815{\pm}20^{\circ}C$. The solidus and liquidus temperatures of $UO_2-Gd_{2}O_3\;and\;UO_2-Er_{2}O_3$ had also been measured, and it was observed that the solidus temperatures of them were lower than the liquidus temperature by $15{\sim}25^{\circ}C$. Measured melting temperatures of $UO_2,\;UO_2-Gd_{2}O_3\;and\;UO_2-Er_{2}O_3$ fuels were as follows:

Studies on the Flowering and Maturity in Sesame 1. Flowering Habit by Different Plant Types (참깨 개화, 등숙에 관한 연구 -제 1 보 참깨 초형에 따른 개화특성에 관한 연구-)

  • Lee, J.I.;Kang, C.W.;Lee, S.T.;Son, E.R.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.29 no.1
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    • pp.76-83
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    • 1984
  • This experiment was performed to investigate the flowering habit of sesame (Sesamum indicum L.). Sesame varieties tested could be classified into 8 different plant types by their morphological traits such as capsule shape, capsule setting habit and branching types among sesame gene pool of Crop Experiment Station, ORD. The first flower was appeared at the lowest node on main stem. Flowers were appeared progressively toward the tip of the main stem and also toward the tips of branches. The interval of flowering for a node was about one day, but 3 to 8 days for the flowers on the tips. Side flowers started at 4 to 5 nodes lower than those of center flower at the same day. Flowers were beared 2 by 1 node on the middle part of flower setting node (7-9) in mono capsule setting habit in spite of its normal is 1 by 1 node on the other nodes. Flowers were beared opposite direction on each node of stem and flowering toward the tip of main stem composed of cross shape between nodes and spiral, reverse of clockwise direction. We called this habit as cross spiral flowering order and cross spiral phyllotaxis. The first flower on branches was appeared when center flower on the 5th node of main stem began to flower. The branches produced at higher nodes on main stem showed larger flowering periods and more number of flowers than that at lower parts. BTB (Branch, Tricapsule, Bicarpels, 4 Loculi) type showed three capsule setting habits and same flowering period both on main stem and branches while BTQ (Branch, Tricapsule, Quadricarpels, 8 Loculi) type showed three capsule setting habit on main stem and mono-capsule setting habit on branches. In BTQ type, the period of flowering was much shorter on branches than on main stem. Branching type was considered more promising than non branching type for the breeding of early maturing high yielding variety because branching type has the advantage of bearing a lot of flowers in comparatively short flowering period.

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