• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.3
• /
• pp.340-345
• /
• 2002

In this experiment, oocytes were collected from goat ovaries available in slaughterhouse by follicle puncture method. Morphologically culturable type of oocytes which having compact, multilayered cumulus granulosa cell complex and evenly granulated cytoplasm, was separated under a stereozoom microscope. Oocytes were washed thoroughly in maturation medium containing TCM-199, $1{\mu}g/ml$ estradiol-$17{\beta}$, 0.5 ${\mu}g/ml$ FSH, $100{\mu}g/ml$ LH, 3 mg/ml BSA and 10% estrus goat serum. Washed oocytes were cultured into maturation medium on granulosa cell monolayer. Culture plate was then kept into $CO_2$ incubator at $38{\pm}1^{\circ}C$, maximum humidity and 5% $CO_2$ for 18 h. After maturation the oocytes were washed thoroughly with maturation medium containing polyvinyl alcohol (PVA) without serum and BSA and further cultured for 12 h for secretory proteins of oocytes. PVA medium was collected, pooled and concentrated by 5000 cut off centrisart. Secretory proteins were separated on 12.5% SDS-PAGE. A total number of 3.41 oocytes per ovary were obtained and 2.17 culturable oocytes per ovary were cultured into maturation medium. After 18 h of maturation, 4,567 oocytes (1.82 oocytes per ovary) were further cultured into serum and BSA free PVA medium for its secretory proteins. Four secretory proteins of oocytes with approximately molecular weight of 45, 55, 65 and 95 kDa were obtained on SDS-PAGE in silver staining and three proteins with approximately molecular weight of 45, 55 and 65 kDa in Coomassie brilliant blue staining. In conclusion, four secretory proteins with approximately molecular weight of 45, 55, 65 and 95 kDa was obtained from in vitro cultured oocytes of goats.

• Journal of Sensor Science and Technology
• /
• v.19 no.4
• /
• pp.291-296
• /
• 2010

Recently, recycling method of waste wafer has been an area of solar cell to cut costs. Micro_blasting is one of the promising candidates for recycling of waste wafer due to their extremely simple and cost-effective process. In this paper, we attempt to explore the effect of micro_blasting and DRE(damage removal etching) process for solar cell. The optimal process conditions of micro_blasting are as follows: $10{\mu}m$ sized $Al_2O_3$ powder, jetting pressure of 400 kPa, and scan_speed of 30 cm/s. And the particles formed on micro_blasted wafer were removed by DRE precess which was performed by using HNA(HF/$HNO_3$/$CH_3COOH$) and TMAH(tetramethyl ammonium hydroxide). Structural analysis was done using a-step and the XRD patterns.

• Proceedings of the KIPE Conference
• /
• 2008.06a
• /
• pp.103-105
• /
• 2008

In grid-interconnection system, a fast, robust and precise phase angle detector is most important to grid synchronization and the active power control. The phase angle can be easily estimated by synchronous dq PLL system. On the other hand under unbalanced voltage condition, synchronous dq PLL system has problem that harmonics occur to phase angle or magnitude of grid voltage because of the effect of the negative sequence components. So, To eliminate the negative sequence components, the PLL method using APF (All Pass Filter) in a stationery reference frame to extract positive sequence components under unbalanced voltage condition is researched. In this paper, we propose a new PLL method with decoupling network using APF in a synchronous reference frame to extract the positive sequence components of the grid voltage under unbalanced grid. The cut-off frequency of APF in a synchronous reference frame can be set to twice of the fundamental frequency comparing with that of APF in a stationery reference frame which is the fundamental frequency. The proposed PLL strategy can detect the phase angle quickly and accurately under unbalanced gird voltages. Simulation and experimental results are presented to verify the proposed strategy under different kind of voltage dips.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.3
• /
• pp.370-374
• /
• 2003

Cell cracking method using a non-collision was evaluated for the possibility of new red ginseng grinding technique. Based on particle size distribution analysis by 1size shaker, the ratios of 100 mesh penetrated particles were 94.9% for hammer mill (group A) and 95.6% for cell crack (group B). The ratio of 120 mesh penetrated particle of group A was higher than that in group B. The particle size distributions for 100 mesh non-penetrated Powder between 2 groups were not significantly different, and particle size distribution analysis by laser scattering analyzer showed that the particle size ranges were 0.77~128.07 ${\mu}{\textrm}{m}$ for group A and 4.24~180.07 ${\mu}{\textrm}{m}$ for group B. The Particle size distribution in group A was more broad than that in group B. The mean particle size in group B was larger than that in group A, while the standard deviation of particle size distribution in group B was less than that in group A. Structural surface characteristics, in group A, particle size distribution was broad and the distribution curve was amorphous. The structure of individual particles was similar to unequal stone which was roughly grinded and had soft cotton-like surface. In the contrary, in group B, particle size distribution was relatively narrow and also individual size particles were ubiquitously distributed. The structure of individual particles was unequal cut stone shape.

• Journal of the Korean Geosynthetics Society
• /
• v.5 no.3
• /
• pp.9-15
• /
• 2006

The Green Wall system is one of segmental concrete crib type earth retaining wall. Green wall is constructed as procedures that lay the front stretchers, rear stretchers and headers then making a rigid body through harden filled soil of interior cell. Recently, Green Wall method is applied in variable cutting ground construction because of advantage which minimize to cut base ground. In case of Green Wall method is constructed with soil nail method, expect that total system stability will increase more than flexible facing because of facing stiffness is big. However, in this case of design, facing stiffness is not considered so that is poor economy. Hence, in this study, stability increasing effect of total system analyze about that soil nail method is constructed with rigidity facing like a Green Wall method. In present study, laboratory model tests was performed for analysis on stability increasing effect of total system about changing stiffness of facing. LEM analysis conducted for evaluation on safety factor of total system sliding that facing condition changed.

• Clinical and Experimental Reproductive Medicine
• /
• v.28 no.3
• /
• pp.183-190
• /
• 2001

Objective: Recently, microdissection of tissue sections has been used increasingly for the isolation of morphologically identified homogeneous cell populations, thus overcoming the obstacle of tissue complexity for the analysis cell-specific expression of macromolecules. The aim of the present study was to establish the minimal conditions required for the RNA extraction and amplification from the cells captured by the laser captured microdissection. Methods : Mouse ovaries were fixed and cut into serial sections (7 im thickness). Oocytes were captured by laser captured microdissection (LCM) method by using PixCell $II^{TM}$ system. The frozen sections were fixed in 70% ethanol and stained with hematoxylin and eosin, while the paraffin sections were stained with Multiple stain. Sections were dehydrated in graded alcohols followed by xylene and air-dried for 20 min prior to LCM. All reactions were performed in ribonuclease free solutions to prevent RNA degradation. After LCM, total RNA extraction from the captured oocytes was performed using the guanidinium isothiocyanate (GITC) solution, and subsequently evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) for glyceraldehyde-3-phosphate-dehydrogenase (GAPDH). Results: With the frozen sections, detection of the GAPDH mRNA expression in the number of captured 25 oocytes were not repeatable, but the expression was always detectable from 50 oocytes. With 25 oocytes, at least 27 PCR cycles were required, whereas with 50 oocytes, 21 cycles were enough to detect GA PDH expression. Amount of the primary cDNA required for RT-PCR was reduced down to at least 0.25 $\grave{i}$ l with 50 oocytes, thus the resting 19.75 il cDNA can be used for the testing other interested gene expression. Tissue-to-slide, tissue-to-tissue forces were very high in the paraffin sections, thus the greater number of cell procurement was required than the frozen sections. Conclusion: We have described a method for analyzing gene expression at the RNA level with the homogeneously microdissected cells from the small amount of tissues with complexity. We found that LCM coupled with RT-PCR could detect housekeeping gene expression in 50 oocytes captured. This technique can be easily applied for the study of gene expression with the small amount of tissues.

• The Korean Journal of Physiology
• /
• v.8 no.2
• /
• pp.67-74
• /
• 1974

The object of this research is aimed to determine the activity of adenyl cyclase in both skeletal muscle sarcolemma and fat cell ghost of epididymal adipose tissue isolated from rats exposed to cold for various length of time in an attempt to evaluate whether the tissue sensitivity to catecholamine is increased when rats are exposed to cold for long periods of time Methods: a)Animals: Albino rats ranging in weight from 150 to 200 gm were used throughout this study. For experimental purposes, the rats are divided into two groups: experimental animals were place4 in a cold room at $4^{\circ}C$, controls being kept at $25^{\circ}C$. At the end of 2, 4, 6, 12, and 16 weeks. exposure to cold the rats were used to measure the adenyl cyclase activity. b) Isolation of plasma membrane from skeletal muscle and adipose tissue: The Plasma membrane of skeletal muscle from hind limbs of rats are prepared by the method employed by Rosenthal et at. and fat cell ghost of epididymal adipose tissue of rats by the method employed by Rodbell. c) Adenyl cyclase assay: Adenyl cyclase activity were measured by the method employed by Marinetti et al. Briefly, plasma membrane was incubated with $3^H-ATP$, various amount of noradrenaline and other incubation mixture at $37^{\circ}C$ for 20 minutes. After stopping the enzyme reaction by immersion in boiling water, carrier 3',5'-AMP was added to the system as a marker and $100\;{\mu}1$ aliquots of incubation mixture were pipetted on $20{\time}20$ Whatman No. 3 MM filter paper for one dimensional chromatography. The cyclic AMP spots were cut off and placed in counting vials containing 10ml of Bray's scintillation cocktail. Radioactivity was determined with a Packard Tri-Carb liquid scintillation counter. The enzyme activity is expressed as nanomoles of cyclic AMP produced per mg of membrane per hour. Result: 1. Average adenyl cyclase activity in the plasma membrane of skeletal muscle before and after noradrenaline administration was significantly higher in the cold-exposed rats as compared to the control. Continuous exposure to cold Produced an increased adenyl cyclase activity before and after noradrenaline administration. Adenyl cyclase activity reached peak levels at the 6 weeks exposure to told and level of adenyl cyclase activity remained high. Noradrenaline administration to the incubation medium induced a significant increase in adenyl cyclase activity and the degree of stimulation were proportional to the hormonal concentration But the rate of inclement in adenyl cyclase activity by noradreasline was the same in both groups. 2. Adenyl cyclase activity in fat cell ghost between cold exposed and control rats showed no significant differences before and after noradreualine administration. In summary, it can be concluded that cold adaptation give rise an increased activity of adenyl cyclase in plasma membrane of skeletal muscle in rats.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.11b
• /
• pp.129-133
• /
• 2005

Vibration transmitted through rolling tire is a major source of road noise in vehicle interior noise on the range of low frequency.($0{\sim}500Hz$) Among various road noises, tire cavity noise has very peak on $200{\sim}250Hz$. And generally it is generated by cavity resonance of tire. In this paper, tire cut-sample is used to calculate the tire cavity frequency. Cavity resonance frequency of tire is measured through vertical/tangential forces at load cell of axle using drum cleat impact. This method is useful to find cavity peak because measured forces do not have complex peaks. And changing the test conditions (air inflation, loads), tire cavity resonance characteristics are identified. Finally, vehicle interior noise is measured as tire/vehicle are changing. As difference of tire vertical force is bigger, interior noise level is higher at cavity frequency. Also we can assume that vehicle sensitivity is important factor at tire cavity noise.

• Toxicological Research
• /
• v.31 no.1
• /
• pp.33-40
• /
• 2015

Bee venom (BV) has long been used in traditional Eastern and Western medicine for chronic inflammation, pain and skin therapy. Human exposure to BV, however, often causes unwanted adverse effects and is even fatal in some cases. Phospholipase $A_2$ ($PLA_2$) of BV is now suspected to play a key role in these adverse effects. We investigated the potential use of $PLA_2$-free bee venom (PBV) as a replacement for BV in cosmetic products. PBV prepared by molecular weight cut-off ultrafiltration exhibits a superior profile in comparison with regular BV, by inhibiting elastase activity and suppressing the induction of nitric oxide (NO) and metalloproteinase-9 (MMP-9), while retaining the effects of cell proliferation and protection against ultraviolet B (UVB)-induced damage in human dermal fibroblast cells. PBV thus appears to be more promising than BV as a cosmetic ingredient with a reduced potential for adverse reactions in the recipient.

• Clinical and Experimental Reproductive Medicine
• /
• v.36 no.4
• /
• pp.311-319
• /
• 2009

Objective: Human embryonic stem cells (hESCs) have the capacity to differentiate into all of the cell types and therefore hold promise for cell therapeutic applications. In order to utilize this important potential of hESCs, enhancement of currently used technologies for handling and manipulating the cells is required. The cryopreservation of hESC colonies was successfully performed using the vitrification and slow freezing-rapid thawing method. However, most of the hESC colonies were showed extremely spontaneous differentiation after freezing and thawing. In this study, we were performed to rapidly collect of early passage hESCs, which was thawed and had high rate of spontaneously differentiation of SNUhES11 cell line. Methods: Four days after plating, partially spontaneously differentiated parts of hESC colony were cut off using finely drawn-out dissecting pipette, which is mechanical separation method. Results: After separating of spontaneously differentiated cells, we observed that removed parts were recovered by undifferentiated cells. Furthermore, mechanical separation method was more efficient for hESCs expansion after thawing when we repeated this method. The recovery rate after removing differentiated parts of hESC colonies were 55.0%, 74.5%, and 71.1% when we have applied this method to three passages. Conclusion: Mechanical separation method is highly effective for rapidly collecting and large volumes of undifferentiated cells after thawing of cryopreserved early passage hESCs.