• Title/Summary/Keyword: Thin membrane

Search Result 525, Processing Time 0.031 seconds

The Ultrastructural Characteristics of Preimplantation Embryonic Envelope in the Rat (흰쥐 초기발생에서 배아막의 미세구조적 특징)

  • 홍순갑;이준영
    • Development and Reproduction
    • /
    • v.2 no.2
    • /
    • pp.157-163
    • /
    • 1998
  • Preimplantation embryos of the rat was examined by the morphological changes in the cortical granule envelope (CGE), blastomere surface, and zona pellucida (ZP) of embryo after cortical reaction. The ultrastructural characteristics and CGE of embryos were observed with the scanning electron microscope and fluorescence microscope. In the ultrastructural characteristic of embryo surface, surface microvilli were shortened and the CGE-like structure existed above microvilli in eight-cell embryo. Rough spongy surface and decreased network numbers were key characters of embryonic ZP compared to unfertilized oocyte. The CGE formed by cortical reaction existed in perivitelline space during embryo development but it was thin and locally distributed ill contrast to fertilized oocyte. The present results indicate that cortical reaction forms cortical granule envelope in perivitelline space and causes not only zona hardening, but also ultrastructural changes in ZP and cell membrane of preimplantation embryos.

  • PDF

A development of outdoor jackets for active senior males (액티브 시니어 남성을 위한 아웃도어 재킷 개발)

  • Kim, Ji-Eun;Kim, Eun-Kyong
    • Journal of the Korea Fashion and Costume Design Association
    • /
    • v.20 no.2
    • /
    • pp.31-46
    • /
    • 2018
  • This study was carried out to offer basic data that can be used for outdoor wear production for active senior males, emerging as a new consumer bracket in the era of rapid aging. To this end, this study modified and complemented the patterns of outdoor jackets for active senior males based on existing outdoor jackets that received the most excellent evaluation. On the basis of the research outdoor wear wearing assessment results, this study confirmed those areas to be modified and proposed areas to be considered in manufacturing outdoor wear for this demographic. As a result of existing outdoor wear's wearing assessment, the jacket of brand B was shown to be the most excellent one. This study actually designed research outdoor wear patterns by modifying the problematic parts through the addition and subtraction of spare length or circumference in the sections where fit satisfaction was low by referring to the selected brands' patterns. The research outdoor wear was designed by referring to the preferred outdoor types and colors that were highlighted in the previous survey result of consumer wearing reality, based on the designs of the outdoor wear receiving the most excellent assessment in wearing assessment. Fabric that specially glued two-layered mesh that bonded the thin membrane of synthetic resin with polyester fabric was used as the material in this study. Wearing assessment was conducted by comparing the manufactured research outdoor wear and the existing outdoor wear selected as excellently assessed outdoor wear. Consequently, this study verified that the wearing fit of the research outdoor wear was more excellent in most items. This study proposed final patterns for outdoor jackets suitable for active senior males through the modification of several items that required improvements as per the wearing assessment of the research outdoor wear.

Morphological Studies on the Epithelium of the Midgut of the Nymph and the adult in the Grasshopper, Oxya sinuosa (우리벼메뚜기 유충과 성충의 중장 점막 상피에 관한 형태학적 연구)

  • Lee, Hyeung-Sik;Lee, Jae-Hyun;Park, Sang-Ock
    • Applied Microscopy
    • /
    • v.20 no.1
    • /
    • pp.105-119
    • /
    • 1990
  • In order to know the morphological characteristics and changes according to the developmental stage, the comparative observations have been studied by light and electron microscope on the midgut(gastric caecum, stomach) of the grasshopper(Oxya sinuosa Mistshenko). The results obtained are summarized as follow : In light microscopic level, the cuboidal shaped cells of the gastric caecum in the 5th instar nymph are differentiated the columnar epithelium in the adult. A number of pigment granules are appeared in the gastric caecum of the 5th instar nymph, however the pigment granules were absent in the adult. Indistinct or undifferentiated folds of the epithelial layer were appeared in the 5th instar nymph, whereas the well-developed folds were appeared the gastric caecum in the adult. The well-developed muscular layers are seen in the 5th instar numph, however in the adult the muscular layers are appeared thin or a few layers. In electron microscopic level, in the midgut epithelium, a number of well-developed rER, a few lipid droplets, multi vesicular bodies, small vesicles and glycogen granules were found. Two types of the pigment granules in the gastric caecum of the 5th instar nymph were appeared, whereas the whorl-membrane, a few secretory granules and one type of the gastro-entero-endocrine cell were found in the adult midgut. The light and dark cells could be distinguished in the stomach epithelim of the 5th instar nymph.

  • PDF

Production of Oleamide, a Functional Lipid, by Streptomyces sp. KK90378

  • Kwon, Jeong-Ho;Hwang, Sung-Eun;Han, Jae-Taek;Kim, Chang-Jin;Rho, Jung-Rae;Shin, Jong-Eon
    • Journal of Microbiology and Biotechnology
    • /
    • v.11 no.6
    • /
    • pp.1018-1023
    • /
    • 2001
  • Oleamide (cis-9-octadecenamide) is endogenous primary amide of fatty acid that is produced in small amounts in animal brains. It is known to induce sleep and to lower temperature by destroying the lipid plasma membrane structure of cells, thereby disclosing gap junction channels. To develop a new biological production method for oleamide, a screening program was conducted to isolate a microorganism producing oleamide. Among 1,500 soil microorganisms tested, KK90378 exhibited a potent positive reaction with Dragendoff`s reagent, used to detect the primary amide of oleamide. KK90378 was identified as a Streptomyces species based on cultural and morpohological characteristics, the presence of diaminopimelic acid in the cell wall, and the sugar patterns for the whole-cell extrat. Streptomyces sp. KK90378 produced oleamide 3 days after culture at $28^{\circ}C$, pH 7.2 A series of purification steps, including hexane extraction, silica gel column, and preparative thin layer chromatographies, were performed for the purification of oleamide. A spectrophotometric analysis using $^1H$, $^13C$-NMR, and GC-MS confirmed that the chemical structure of the purified oleamide was identical to that of authentic oleamide.

  • PDF

Micromachined ZnO Piezoelectric Pressure Sensor and Pyroelectric Infrared Detector in GaAs

  • Park, Jun-Rim;Park, Pyung
    • Journal of Electrical Engineering and information Science
    • /
    • v.3 no.2
    • /
    • pp.239-244
    • /
    • 1998
  • Piezoelectric pressure sensors and pyroelectric infrared detectors based on ZnO thin film have been integrated with GaAs metal-semiconductor field effect transistor (MESFET) amplifiers. Surface micromachining techniques have been applied in a GaAs MESFET process to form both microsensors and electronic circuits. The on-chip integration of microsensors such as pressure sensors and infrared detectors with GaAs integrated circuits is attractive because of the higher operating temperature up to 200 oC for GaAs devices compared to 125 oC for silicon devices and radiation hardness for infrared imaging applications. The microsensors incorporate a 1${\mu}$m-thick sputtered ZnO capacitor supported by a 2${\mu}$m-thick aluminum membrane formed on a semi-insulating GaAs substrate. The piezoelectric pressure sensor of an area 80${\times}$80 ${\mu}$m2 designed for use as a miniature microphone exhibits 2.99${\mu}$V/${\mu}$ bar sensitivity at 400Hz. The voltage responsivity and the detectivity of a single infrared detector of an area 80${\times}$80 $\mu\textrm{m}$2 is 700 V/W and 6${\times}$108cm$.$ Hz/W at 10Hz respectively, and the time constant of the sensor with the amplifying circuit is 53 ms. Circuits using 4${\mu}$m-gate GaAs MESFETs are fabricated in planar, direct ion-implanted process. The measured transconductance of a 4${\mu}$m-gate GaAs MESFET is 25.6 mS/mm and 12.4 mS/mm at 27 oC and 200oC, respectively. A differential amplifier whose voltage gain in 33.7 dB using 4${\mu}$m gate GaAs MESFETs is fabricated for high selectivity to the physical variable being sensed.

  • PDF

EXPERIMENTAL STUDY ON THE ANTERIORLY DISPLACED TEMPOROMANDIBULAR JOINT MENISCUS IN RABBIT (실험적으로 전방이동시킨 가토의 악관절원판에 관한 연구)

  • Choi, Nack-Jun;Chang, Young-Il
    • The korean journal of orthodontics
    • /
    • v.21 no.1 s.33
    • /
    • pp.53-76
    • /
    • 1991
  • The study was designed to analyse the reorganization of the rabbit TMJ meniscus which was anteriorly displaced by surgery. The author compared the anteriorly displaced groups with control group. After surgical opening of the left rabbit TMJ space, cut the posterior attachment of the meniscus, and pushed it under the undercut area of the condyle head. Experimental groups were sacrificed by 1, 2, 4, 8 weeks after surgery. The samples were analysed with light microscope under T-B stain and electron microscope. The results were as follows: 1) The rabbit TMJ meniscus consisted of thick anterior and posterior band running different way, and comparative thin intermediate band runining antero-posteriorly. 2) Round oval shape chondrocyte-like cells were imbeded between the collagen fiber bundles and composed of proteoglycan granules, that showed metachromasia with toluidine blue, around the cell matrix. 3) Type II collagen fiber bundles in experimental group occured degenerative changes in organic patterns at 8 weeks, but those of type I collagen fiber bundles sustained longer, 4) The typical fibrocartilage of the rabbit TMJ meniscus was changed into fibrotic mode in process of time and showed the degenerative changes, which contained hyperplasia, calcification, resorption and hyalinization in the connective tissue. 5) The hyperplastic change of the synovial membrane in 4 week group and transitional change from fibrocyte to chondrocyte in cell type in 8 week group were observed. 6) The diameters of collagen fibers were diminished with the degenerative changes, the shape of the fibers became wavier and more nonorganic in running pattern and fiber bundle spaces widened.

  • PDF

Preparation of Hydrophilic-Hydrophobic Composites by A Concentrated Emulsion Polymerization Method and Their Permselectivity to Mixture of Water-Ethanol (고농축에멀션중합방법을 이용한 분리막제조와 선택적 흡수성 연구)

  • Park, Jun-Seo
    • Applied Chemistry for Engineering
    • /
    • v.8 no.1
    • /
    • pp.29-38
    • /
    • 1997
  • In the w/o concentrated emulsion, the volume fraction of the dispersed is greater than 0.74 and the hydrophilic liquid is dispersed in the hydrophobic liquid of the continuous phase. The emulsion has the same appearance and behaviour as a gel. The polarity of the hydrophilic liquids and hydrophobic liquids, the pH and the ionic strength of the hydrophilic liquid are found to be important factors in the stability at the polymerization temperature such as $50^{\circ}C$. The lower the polarity of the hydrophobic liquid and the higher the polarity of the hydrophilic liquid, the more stable the emulsion. Electron microscopy studies of the hydrophilic-hydrophobic polymer composites show that the particles of polyacrylamide, the dispersed phase, are separated by he network of the thin film of polystyrene, the continuous phase. This hydrophilic-hydrophobic polymer composites show higher permselectivity to water in the mixture of water-ethanol. The pervaporation experiment shows that the selectivity of the membrane ranges between 4-40 and increases with increasing enthanol concentration in the feed. The rate of permeation decreases with increasing ethanol concentration in the feed.

  • PDF

Oogenesis of Microphysogobio yaluensis (Pisces, Cyprinidae) in the Korean Endemic Species (한국고유종 돌마자의 난자형성과정)

  • Kim, Jae Goo;Reu, Dong Suck;Park, Jong Yong
    • Korean Journal of Ichthyology
    • /
    • v.29 no.4
    • /
    • pp.252-257
    • /
    • 2017
  • The oogenesis of the Microphysogobio yaluensis was investigated using light microscopy. Various developmental oocytes appeared in the ovary of the M. yaluensis. The oogenesis is largely divided into four stages: nuclear-chromatin stage, peri-nucleoli stage, vitellogenesis (yolk vesicle and yolk granule stages), and mature stage. The nuclear-chromatin is distributed in a large germinal vesicle as threads. The peri-nucleoli stage has many acidic nucleoli lining at the inner side of the nuclear membrane and an egg envelope just weakly starts. As the oogenesis gradually proceeds, they change to the vitellogenesis stage. The oocyte become to drastically increase and the marginal area of the ooplasm is covered with many vacuoles showing no negative reactions with hematoxylin and eosin staining, called the yolk vesicle stage. Many yolk vesicles-owned oocyte largely increase and as the development continues, its ooplasm is changed from the yolk vesicles to the yolk granules of eosinophilic. At the mature stage, lots of granules merged into a big yolk mass, acidophilic. Even at the mature stage, the egg envelope was still thin between the ooplasm and the follicular layer of the oocyte.

Development of the wooden window design implementing D.I.Y. modular system (D.I.Y. Modular 방식을 도입한 목재 창 디자인 개발)

  • Kim, Jin-Young;Kim, Do-Yeon;Roh, Yang-Mi;Park, Hyo-Mi
    • Archives of design research
    • /
    • v.17 no.4
    • /
    • pp.401-404
    • /
    • 2004
  • The proposal defines a Do It Yourself system that radically changes the traditional concept of window. it is based on a D.I.Y. system that allows the users to fully customize its windows according to his needs, combining a wood frame with different elements. At the same time, it is preserving the basic function of light and ventilation and defining a new aesthetic code. Despite the restriction of size and shape, the user can choose among many different elements to increase the space efficiency he needs and to give a more enjoyable perspective to the window both in and out door. Also, All the elements are standard and they can be mass-produced according to specific market needs. Therefore, the window of the future will not be just a thin membrane in between the inside and the outside, but it will also play an important "identification role. According to each individual pick, these new windows will help to give identify to anonymous metropolitan areas and to the people living within them.

  • PDF

A Study on the Oogenesis of Pale Chub (Zacco platypus) (피라미(Zacco platypus)의 난자형성에 관한 연구)

  • Jang, Seung-Jae;Kim, Dong-Heui;Reu, Dong-Suck;Deung, Young-Kun
    • Applied Microscopy
    • /
    • v.25 no.3
    • /
    • pp.63-74
    • /
    • 1995
  • The development of pale chub oocyte from the immature oogonium to mature oocyte was investigated by light and electron microscope. The cytoplasm of pale chub oogonia was acidic and many vesicles were located at inner side of nuclear membrane. In primary oocytes, yolk vesicles were distributed in cytoplasm. Also, fibrous materials and protuberances were distributed on the surface of zona radiata. The nucleus of secondary oocyte was enlarged and yolk vesicles in cytoplasm migrated to zona radiata. In early egg, yolk mass are formed and yolk vesicles were located at inner side of zona radiata. Three-layered zona radiata was about $3{\mu}m$ in thickness. The three layers were an outer fibrous material layer, a middle nurse cell layer in which microvilli of early egg cytoplasm contact with processes of nurse cells, and an inner layer with high electron density. In mature egg, euchromatin and a germinal vesicle were developed, mitochondria, free ribosomes, and yolk mass were distributed in cytoplasm. But, yolk vesicles were disappeared. Specially, zona radiata of matured eggs were better thin than the one of immature eggs In conclusion, it is summerized that the oogenesis of pale chub were the increase of cell size, the formation and accumulation of yolk, the decrease in nucleat electron density, changes of zona radiata, and the development of microvilli.

  • PDF