• Journal of Embryo Transfer
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• v.19 no.2
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• pp.113-119
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• 2004

The purpose of the present study was to examine whether collection time affects results of oocyte recovery from superovulated goats. Fiftyty-one mature Korean native goats, maintained in a pen under natural day length and fed hay ad libitum, were pretreated with progestagen impregnated CIDR for 10 days and then the goats were divided into two groups. One group of the goats received a single intramuscular injection of 1,000 IU PMSG on Day 8 of CIDR insertion. The other group of the goats received twice daily intramuscular injections of a total of 70 mg FSH for 3 days from Day 8 of CIDR. All the gonadotropin treated goats were injected with 10 mg $PGF_{2\alpha}$ on Day 8 and 400 IU hCG in the afternoon on Day 10. For oocyte recovery, donor goats were fasted 24 h before operation. Anesthesia was induced by intravenous injection of 2% xylazine(0.2 mg/kg body weight) and ketamin(11 mg/kg body weight). In vivo oocytes were recovered by follicle aspiration or oviduct flushing at 29 to 34, 35 to 40 and 41 to 50 h after hCG injection through mid-ventral incision. There was no significant difference in the mean number of CL and oocytes recovered. Oocyte collection at 29 to 40 h after hCG increased(P<0.05) the recovery rate of ovulated oocytes in oviducts compared to 41 to 50 h. The same results were also observed in the recovery of follicular oocytes. Oocyte grade was not affected by collection time. When oocytes were collected from follicular oocytes at 41 to 50 h after hCG, the recovery rate of Grade II oocytes was the lowest(P<0.05). From these results, it is suggested that oocyte recovery at 35 to 40 h after hCG will be successful for further use.

• The korean journal of orthodontics
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• v.28 no.3 s.68
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• pp.461-477
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• 1998

To evaluate the relapse pattern and long-term stabilities depanding on surgical methods following orthognathic surgery of Cl III patients, the author selected 24 subjects(10 male, 14 female) operated by SSRO and 26 subjects(10 male,16 female) operated by IVRO. Each subject took four lateral cephalograms : just before surgery(T1), within 48hrs after surgery(T2), 4-8 wks after surgery(T3), 6 month or more after surgery(T4), and the landmarks were digitized. The differences of relapse patterns in each interval between two groups were compared and the significance of correlation among the variables of each group was tested. The obtained results are as follows ; 1. Horizontal early relapse was forward movement of mandible in SSRO group, as compared to the backward movement in IVRO group, and there was a statistical significance between the two groups. 2. Vertical early and late relapses were decreases in anterior facial height in both groups and there was no statistical significance between the two groups. 3. There was a statistical significance in negative correlation between mandibular horizontal late relapse and surgical change of articular angle in SSRO group. 4. There was a statistical significance in negative correlation between amount of mandibular set-back and mandibular horizontal early relapse in both groups.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.1
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• pp.57-64
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• 2013

Cells can resist and even recover from stress induced by acute hypoxia, whereas chronic hypoxia often leads to irreversible damage and eventually death. Although little is known about the response(s) to acute hypoxia in neuronal cells, alterations in ion channel activity could be preferential. This study aimed to elucidate which channel type is involved in the response to acute hypoxia in rat pheochromocytomal (PC12) cells as a neuronal cell model. Using perfusing solution saturated with 95% $N_2$ and 5% $CO_2$, induction of cell hypoxia was confirmed based on increased intracellular $Ca^{2+}$ with diminished oxygen content in the perfusate. During acute hypoxia, one channel type with a conductance of about 30 pS (2.5 pA at -80 mV) was activated within the first 2~3 min following onset of hypoxia and was long-lived for more than 300 ms with high open probability ($P_o$, up to 0.8). This channel was permeable to $Na^+$ ions, but not to $K^+$, $Ca^+$, and $Cl^-$ ions, and was sensitively blocked by amiloride (200 nM). These characteristics and behaviors were quite similar to those of epithelial sodium channel (ENaC). RT-PCR and Western blot analyses confirmed that ENaC channel was endogenously expressed in PC12 cells. Taken together, a 30-pS ENaC-like channel was activated in response to acute hypoxia in PC12 cells. This is the first evidence of an acute hypoxia-activated $Na^+$ channel that can contribute to depolarization of the cell.

• Food Science and Preservation
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• v.18 no.2
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• pp.256-265
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• 2011

To investigate the effect of a solar salt on Kimchi fermentation, Chinese cabbages were brined with four-years aged solar salt (FS), one-year aged solar salt (OS), and purified salt (PS). The Kimchi was fermented at $7^{\circ}C$ for 33 days. The changes in pH and acidity of the Kimch brined with PS was slower than those of Kimchis brined with FS and OS. In the Kimchis with FS and OS, lactic acid bacteria (LAB) counts increased from 7.10~7.22 log CFU/mL at 0 day to 9.26~9.42 log CFU/mL at 12 days, after which counts slightly decreased to 8.04~8.75 log CFU/mL by 33 days of fermentation. The LAB counts of the kimchi with PS slowly increased from 7.24 log CFU/mL at 0 day to 8.99 log CFU/mL at 27 days, after then which counts sharply decreased to 7.92 log CFU/mL by 33 days of fermentation. Yellowness (b) color values of the kimchi with PS (59.10) was higher than the Kimchi with FS (53.68) and the Kimchi with OS (53.77). Hardness of the Kimchi with FS was more firm than the other Kimchis after 33 days storage. Sensory evaluation of the Kimchi with FS showed higher score than that of the other Kimchis.

• Applied Chemistry for Engineering
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• v.1 no.1
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• pp.35-43
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• 1990

A series of $TiO_2-SiO_2$catalysts were prepared by coprecipitation from the mixed solution of titanium tetrachloride and sodium silicate. Some of the samples were treated with 1N $H_2SO_4$ and used as modified catalysts. The catalytic activities of modified catalysts were higher than those of unmodified catalysts, and the effect of modification on the catalytic activity was higher for 2 - propanol dehydration than for cumene dealkylation. The catalytic activity of unmodified catalysts was correlated with their acid amount for the above two reactions. As $TiO_2-SiO_2$ catalysts had relatively large amount of weak acid sites and small amount of strong acid sites, the catalytic activity for 2 - propanol dehydration was higher than that for cumene dealkylation. The effect of modification on catalytic activity increased with increasing $TiO_2$content of the catalysts. Actually, $92-TiO_2-SiO_2/SO_4{^2}$had the highest increment in catalytic activity and $10-TiO_2-SiO_2/SO_4{^2}$had the lowest increment for the 2 - propanol dehydration.

• Economic and Environmental Geology
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• v.48 no.4
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• pp.273-285
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• 2015

The extensive hydrothermal deposits have been found, for the first time, on the western TA25 seamount caldera in the Tonga arc. The seafloor hydrothermal vents are active and immature, emitting the transparent fluids of which temperatures range from $150^{\circ}C$ to $242^{\circ}C$ (average=$203^{\circ}C$). The recovered hydrothermal sulfides are mainly composed of sphalerite, pyrite, marcasite, galena, chalcopyrite, covellite, tennantite, enargite and sulfates such as barite, gypsum/anhydrite. Predominant sphalerite categorize it into Zn-rich hydrothermal ore body. Zn-rich sulfide ores have minor enargite, indicating that mineralization occurred in high sulfidation environment. The proportion and FeS content of sphalerite increase from outside to inside of the hydrothermal ores, respectively. In particular, sphalerite has a great silver content (up to ~10 wt.%). Chalcopyrite is more frequently observed in mound than in the chimney, implying mineralization temperature in the mound is higher than in the chimney. Homogenization temperatures and salinities from fluid inclusions in barite at the mound range from $148^{\circ}C$ to $341^{\circ}C$ (average=$213^{\circ}C$) and 0.4 to 3.6 equiv. wt.% NaCl, respectively. Homogenization temperatures suggest that sulfides in the mound mineralized at a higher temperature (${\geq}200^{\circ}C$) than in the chimney.

• Electrical & Electronic Materials
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• v.12 no.7
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• pp.7-11
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• 1999

Fully sealed field emission display in size of 4.5 inch has been fabricated using single-wall carbon nanotubes-organic vehicle com-posite. The fabricated display were fully scalable at low temperature below 415$^{\circ}C$ and CNTs were vertically aligned using paste squeeze and surface rubbing techniques. The turn-on fields of 1V/${\mu}{\textrm}{m}$ and field emis-sion current of 1.5mA at 3V/${\mu}{\textrm}{m}$ (J=90${\mu}{\textrm}{m}$/$\textrm{cm}^2$)were observed. Brightness of 1800cd/$m^2$ at 3.7V/${\mu}{\textrm}{m}$ was observed on the entire area of 4.5-inch panel from the green phosphor-ITO glass. The fluctuation of the current was found to be about 7% over a 4.5-inch cath-ode area. This reliable result enables us to produce large area full-color flat panel dis-play in the near future. Carbon nanotubes (CNTs) have attracted much attention because of their unique elec-trical properties and their potential applica-tions [1, 2]. Large aspect ratio of CNTs together with high chemical stability. ther-mal conductivity, and high mechanical strength are advantageous for applications to the field emitter [3]. Several results have been reported on the field emissions from multi-walled nanotubes (MWNTs) and single-walled nanotubes (SWNTs) grown from arc discharge [4, 5]. De Heer et al. have reported the field emission from nan-otubes aligned by the suspension-filtering method. This approach is too difficult to be fully adopted in integration process. Recently, there have been efforts to make applications to field emission devices using nanotubes. Saito et al. demonstrated a car-bon nanotube-based lamp, which was oper-ated at high voltage (10KV) [8]. Aproto-type diode structure was tested by the size of 100mm $\times$ 10mm in vacuum chamber [9]. the difficulties arise from the arrangement of vertically aligned nanotubes after the growth. Recently vertically aligned carbon nanotubes have been synthesized using plasma-enhanced chemical vapor deposition(CVD) [6, 7]. Yet, control of a large area synthesis is still not easily accessible with such approaches. Here we report integra-tion processes of fully sealed 4.5-inch CNT-field emission displays (FEDs). Low turn-on voltage with high brightness, and stabili-ty clearly demonstrate the potential applica-bility of carbon nanotubes to full color dis-plays in near future. For flat panel display in a large area, car-bon nanotubes-based field emitters were fabricated by using nanotubes-organic vehi-cles. The purified SWNTs, which were syn-thesized by dc arc discharge, were dispersed in iso propyl alcohol, and then mixed with on organic binder. The paste of well-dis-persed carbon nanotubes was squeezed onto the metal-patterned sodalime glass throuhg the metal mesh of 20${\mu}{\textrm}{m}$ in size and subse-quently heat-treated in order to remove the organic binder. The insulating spacers in thickness of 200${\mu}{\textrm}{m}$ are inserted between the lower and upper glasses. The Y\ulcornerO\ulcornerS:Eu, ZnS:Cu, Al, and ZnS:Ag, Cl, phosphors are electrically deposited on the upper glass for red, green, and blue colors, respectively. The typical sizes of each phosphor are 2~3 micron. The assembled structure was sealed in an atmosphere of highly purified Ar gas by means of a glass frit. The display plate was evacuated down to the pressure level of 1$\times$10\ulcorner Torr. Three non-evaporable getters of Ti-Zr-V-Fe were activated during the final heat-exhausting procedure. Finally, the active area of 4.5-inch panel with fully sealed carbon nanotubes was pro-duced. Emission currents were character-ized by the DC-mode and pulse-modulating mode at the voltage up to 800 volts. The brightness of field emission was measured by the Luminance calorimeter (BM-7, Topcon).

• Journal of Plant Biotechnology
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• v.33 no.1
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• pp.11-18
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• 2006

Salt stress is one of major environmental factors influencing plant growth and development. To identify salt tolerance determinants in higher plants, a large-scale screen was conducted with a bialaphos marker-based T-DNA insertional collection of Arabidopsis ecotype C24 mutants. One line for salt stress-sensitive mutant (referred to as ssm1) exhibited increased sensitivity to both ionic (NaCl) and nonionic (mannitol) osmotic stress in a root growth assay. This result suggests that ssm1 mutant is involved in ion homeostasis and osmotic compensation in plant. Molecular cloning of the genomic DNA flanking T-DNA insert of ssm1 mutant was achieved by mutant genomic DNA library screening. T-DNA insertion appeared in the first exon of an open reading frame on F3M18.7, which is the same as AtSYP61. SSM1 is SYP61/OSM1 that is a member of the SNARE superfamily of proteins required for vesicular/target membrane fusions and factor related to abiotic stress.

• Economic and Environmental Geology
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• v.39 no.1 s.176
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• pp.9-25
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• 2006

Baekun gold-silver deposit is an epithermal quartz vein that is filling the fault zone within Triassic or Jurassic foliated granodiorite. Mineralization is associated with fault-breccia zones and can be divided into two stages. Stage I which can be subdivided early and late depositional stages is main ore mineralization and stage II is barren. Early stage I is associated with wallrock alteration and the formation of sulfides such as arsenopyrite, pyrite, pyrrhotite, sphalerite, marcasite, chalcopyrite, stannite, galena. Late stage I is characterized by Au-Ag mineralization such as electrum, Ag-bearing tetrahedrite, stephanite, boulangerite, pyrargrite, argentite, schirmerite, native silver, Ag-Te-Sn-S system, Ag-Cu-S system, pyrite, chalcopyrite and galena. Fluid inclusion data indicate that homogenization temperatures and salinity of stage I range from $171.6^{\circ}C\;to\;360.8^{\circ}C\;and\;from\;0.5\;to\;10.2\;wt.\%\;eq.$ NaCl, respectively. It suggest that ore forming fluids were cooled and diluted with the mixing of meteoric water. Also, Temperature (early stage I: $236\~>380^{\circ}C,\;$ late stage $I: <197\~272^{\circ}C$) and sulfur fugacity (early stage $I:\;10^{-7.8}$ a atm., late stage I: $10^{-14.2}\~10^{-l6}atm$.) deduced mineral assemblages from stage 1 decrease with paragenetic sequence. Sulfur ($2.4\~6.1\%_{\circ}$(early stage $I=3.4\~5.3\%_{\circ},\;late\;stage\;I=2.4\~6.1\%_{\circ}$)), oxygen ($4.5\~8.8\%_{\circ}$(quartz: early stage $I=6.3\~8.8\%_{\circ}$, late stage $I=4.5\~5.6\%_{\circ}$)), hydrogen ($-96\~-70\%_{\circ}$ (quartz: early stage $I=-96\~-70\%_{\circ},\;late\;stage\;f=-78\~-74\%_{\circ},\;calcite:\;late\;stage\;I=-87\~-76\%_{\circ}$)) and carbon ($-6.8\~-4.6\%_{\circ}$ (calcite: late stage I)) isotope compositions indicated that hydrothermal fluids may be magmaticorigin with some degree of mixing of another meteoric water for paragenetic time.

• Korean Journal of Veterinary Research
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• v.32 no.3
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• pp.381-387
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• 1992

Gill epithelia of normal rainbow trout fingerlings and abnormal ones suffering bacterial gill disease by experimental infection were examined by transmitting electron microscopy (TEM) and scanning electron microscopy (SEM). TEM observations revealed that Flavobacterium branchiophila consisted of slender rods measuring 0.5 by 5 to $8{\mu}m$, and they had which were long, thin, flexible filaments measuring approximately 4 nm by $1{\mu}m$, and packed together to organize into bundles. Morphological alterations of the diseased epithelia started at hypertrophy of the lamellar epithelium. F branchiophila attached to the gill surface of infected fish through pili with a regular distance, and did not invade into gill tissue. In SEM observations, normal surface ultrastructure of epithelial cell in the outermost layer were characterized by a typical labyrinth-like structure branching and anastomosing microridges on the cell surface. Hyperplastic lesions in experimentally infected gill were most serious at near the tips. Each filament exhibited a club-like, and fusion between the filaments was sometimes observed at their tips. On the surface of gill filaments, thread-like bacterial cells attached and were entangled. The bacterial cells almost covered the surface. After immersion in 5 % NaCl, the cell of F branchiophila, however, appeared to be indeterminate shape.