• Molecules and Cells
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• 제21권3호
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• pp.428-435
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• 2006

Specific interaction of the epsin N-terminal homology(ENTH) domain with the plasma membrane appears to bridge other related proteins to the specific regions of the membrane that are invaginated to form endocytic vesicles. An additional $\alpha$-helix, referred to as helix 0 (H0), is formed in the presence of the soluble ligand inositol-1,4,5-trisphosphate [$Ins(1,4,5)P_3$] at the N terminus of the ENTH domain (amino acid residues 3-15). The ENTH domain alone and full-length epsin cause tubulation of liposomes made of brain lipids. Thus, it is believed that H0 is membrane-inserted when it is coordinated with the phospholipid phosphatidylinositol-4,5-bisphosphate [$PtdIns(4,5)P_2$], resulting in membrane deformation as well as recruitment of accessory factors to the membrane. However, formation of H0 in a real biological membrane has not been demonstrated. In the present study, the membrane structure of H0 was determined by measurement of electron paramagnetic resonance (EPR) nitroxide accessibility. H0 was located at the phosphate head-group region of the membrane. Moreover, EPR line-shape analysis indicated that no pre-formed H0-like structure were present on normal acidic membranes. $PtdIns(4,5)P_2$ was necessary and sufficient for interaction of the H0 region with the membrane. H0 was stable only in the membrane. In conclusion, the H0 region of the ENTH domain has an intrinsic ability to form H0 in a $PtdIns(4,5)P_2$-containing membrane, perhaps functioning as a sensor of membrane patches enriched with $PtdIns(4,5)P_2$ that will initiate curvature to form endocytic vesicles.

• 한국레이저가공학회지
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• 제14권2호
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• pp.8-12
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• 2011

As the aged population grows around the world, many medical instruments and devices have been developed recently. Among the devices, a drug delivery stent is a medical device which requires precision machining. Conventional drug delivery stent has problems of residual polymer and decoating because the drug is coated on the surface of stent with the polymer. If the drug is impregnated in micro hole array on the surface of the stent, the problem can be solved. Micro sized holes are generally fabricated by laser machining; however, the fabricated holes do not have an enough aspect ratio to contain the drug or a good surface finish to deliver it to blood vessel tissue. To overcome these problems, we propose a vibration-assisted machining mechanism with PZT (Piezoelectric Transducers) for the fabrication of micro sized holes. If the mechanism vibrates the eyepiece of the laser machining head, the laser spot on the workpiece will vibrate vertically because objective lens in the eyepiece shakes by the mechanism's vibration. According to the former researches, the vibrating frequency over 20kHz and amplitude over 500nm are preferable. The vibration mechanism has cylindrical guide, hollowed PZT and supports. In the cylinder, the eyepiece is mounted. The cylindrical guide has upper and low plates and side wall. The shape of plates and side wall are designed to have high resonating frequency and large amplitude of motion. The PZT also is selected to have high actuating force and high speed of motion. The support has symmetrical and rigid characteristics.

• Parasites, Hosts and Diseases
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• 제40권2호
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• pp.67-73
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• 2002

The present study was performed to observe tegumental ultrastructure of Echinoparyphium recurvatum according to developmental stages. Worms (1, 3, 5 and 15-day old) were recovered from chicks experimentally infected with metacercariae from radix auricularia coreana. One-day old worms were elongated and ventrally concave, and covered with peg-like tegumental spines except the adjacent areas of the head crown and excretory pore. Type I sensory papillae were distributed on the lip of the oral sucker, and grouped ciliated papillae were around the oral sucker. Peg-like tegumental spines were densely distributed on the anterior surface of the ventral sucker level. The ventral sucker had an aspinous tegument and no sensory papillae. Tegumental spines on the posterior surface of the ventral sucker level were sparsely distributed and disappeared posteriorly. In 3 and 5-day old worms, the tegument around the oral sucker was aspinose and wrinkled concentrically. The ventral sucker had a wrinkled tegument and many bulbous papillae. Type I sensory papillae were distributed between the bulbous papillae. Tegumental spines were spade-shaped with a terminal tip. A total of 45 collar spines including 4 end group ones on both ventral corners was alternately arranged in 2 rows. The 15-day old worms were very stout and their tegumental spines were tongue-shaped without a terminal tip, From the above results, it is confirmed that the surface ultrastructure of E. recurvatum was generally similar to that of other echinostomatid flukes. However, some features, i.e., morphological change of tegumental spines and appearence of sensory papillae on the ventral sucker according to development, and number, shape and arrangement of collar spines, were characteristic, which may be of taxonomic and bioecological significance.

• 한국정밀공학회지
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• 제22권10호
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• pp.174-185
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• 2005

This paper presents the design, fabrication, and testing results of a dual stage actuator system for a fine positioning of magnetic heads in magnetic disk drives. A novel rotary microactuator which is electrostatically driven and utilized as a secondary actuator was designed. The stator and rotor electrodes in the microactuator was revised to have the optimal shapes and hence produces much higher rotational torque compared with the conventional comb-shape electrodes. The microactuators were successfully fabricated using SoG(silicon on glass) processing technology, which is known as being cost-effective. The fabricated microactuator has the structural thickness of $45{\mu}m$ with the gap width of approximately $3{\mu}m$. The dynamic characteristic of microactuator/slider assembly was investigated, and its natural frequency and DC gain were measured to be 3.4kHz and 32nm/V, respectively. The microactuator/slider assembly was integrated into a HDD model V10 of Samsung Electronics Co. and a dual servo algorithm was tested to explore the tracking performance of dual stage actuator system where the LDV signals instead of magnetic head signals were used. Experimental results indicate that this system achieves the tracking accuracy of 30nm. This value corresponds to a track density of 85,000 track per inch(TPI), which is about 3 times greater than that of current hard disk drives.

• 대한수의학회지
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• 제36권1호
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• pp.235-245
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• 1996

Serial ultrasonographic examinations were performed on 9 pregnant Korea Jin-do bitches that were the Korean native breed, from days 15 to 60 pregnancy to determine the time of first detection and ultrasonographic appearance of the fetal and extra-fetal structures of pregnancy. Gestational age was timed from the day of ovulation (Day 0), which was estimated to occur when plasma progesterone concentration was first increased above 4.0 ng/ml. Gestational ages at earliest detection of the following fetal and extra-fetal structures were; gestational sac at days 17 to 22; placental layers in the uterine wall at days 20 to 24; zonary placenta at days 25 to 28; yolk sac membrane at days 22 to 24; amnionic membrane at days 27 to 29; embryo initial detection at days 21 to 23; fetal heartbeat at days 21 m 25; bipolar shape embryo at days 25 to 26; fetal movement at days 28 to 31; limb buds at days 31 to 35; anechoic area in head at days 31 to 36; stomach at days 34 to 37; urinary bladder at days 34 to 37; skeleton at days 36 to 38; dorsal sagittal tubular structure in vertebrae at days 36 to 38; lung hyperechoic vs liver at days 37 to 39; liver hypoechoic vs abdomen at days 37 to 40 and kidney at days 43 to 48, respectively.

• The Korean Journal of Pain
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• 제10권2호
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• pp.225-230
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• 1997

Background: Authors modified the traditional continuous axillary brachial plexus block technique of Selander for purpose of increasing success rate and decreasing complications by use of commercial epidural anesthesia set. Method: Thirty-nine patients scheduled for upper extremity operations were injected with 40 ml of anesthetic solution by axillary perivascular technique, using 23~25G immobile needle at 2 cm from the pectoralis major. Tuohy needle was immediately introduced at 4 cm from the pectoralis major and pierced the expanded neurovascular sheath at an angle of 30 degree to the skin. The "pop" was well noted well. Needle was advanced 0.5 to 3.0 cm and epidural catheter introduced through the needle. After removal of needle, occlusive dressing was done. Tip of catheter and spread of solution were demonstrated by fluoroscopy with contrast dye after completion of procedure. Result: Catheter insertion was successful at first attempt for all case. Total length of insertion was from 6 to 13($10.0{\pm}1.7$) cm. Tip of catheter was placed in infraclavicular space(66.7%), about the humeral head(17.9%) and in upper arm in 3 cases as U-shape(7.9%). Catheters were maintained for $6.7{\pm}2.6$(3-12) days. There were no complications such as: perforation of major vessels, needle trauma to nerve, infection, bleeding or hematoma. Conclusion: This study demonstrated continuous axillary brachial plexus block with epidural anesthesia set is safe, easy and convenient modification of technique of Selander.

• 한국의류학회지
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• 제32권5호
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• pp.821-833
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• 2008

The purpose of this study is to provide basic information about body proportion characteristics, and the level of body cathexis and fit satisfaction related to those characteristics. It is hoped that this will help to improve ready-to-wear satisfaction in middle-aged women. In order to achieve this purpose, the body proportion characteristics of middle-aged women were measured and were compared with that of standard and ideal body types. Then, the body cathexis and fit satisfaction according to these characteristics was analyzed. Finally, the following results were obtained. First, the average height of middle-aged women was 6.87 head, waist length was 58.9% of height, and knee length was 25.6% of height. In frontal appearance, the hip width, shoulder width, and chest width were wider than waist width(24%, 20%, and 11% respectively). Chest and hip depths was thicker than waist depth(19% and 17% respectively). Second, in lengths proportion, their lower body was shorter than the standard body shape for women in their 20s'. Also the difference between the width of frontal appearance and depth proportion of side appearance was small, suggesting a more slender silhouette among the middle aged women. Finally, middle-aged women who were not wide or big in the chest had higher satisfaction with their bodies. As shoulder width and chest depth became small, the fit satisfaction of upper clothes increased. While longer lower body had higher fit satisfaction with pants crotch, shorter lower body had higher fit satisfaction with waist and abdominal parts.

• 한국초지조사료학회지
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• 제11권1호
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• pp.1-5
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• 1991

Tall fescue(Festuca amndinacea Schreb.) is a productive pasture grass that is widely adapted to the soil and climate of Korea. It is regarded, however, as relatively low in palatability and nutritive value. On the other hand, Italian ryegrass(lo1ium rnultz$om Lam.) is highly nutritious and palatable, but is essentially weak in cold tolerance. Numerous investigators have succeeded in producing hybrids between Lolium spp. and Festuca spp. but no improved varieties have resulted. Therefore, intergeneric hybridization of Italian ryegrass with tall fescue is employed in 1984 to improve the adaptive and cold resistance quality of Italian ryegrass. In the mean time, F1-hybrid plants obtained by crossing Italian ryegrass x tall fescue were observed in open field. The results are summarized as follows: 1. Leaf-size and silica cell hair were intermediate between the types of parents but the shape of auricle tended to show Italian ryegrass and auricle-cilia to show tall fescue. 2. Roots of $F_1$-hybrid plants were mainly distributed at top soil and did not produced florescence material. 3. Head type of hybrids was intermediate between the types of parents but ray length was somewhat less than the length of tall fescue ray. Typical Italian ryegrass or tall fescue-like phenotypes were not observed. 4. Anthers of $F_1$-hybrid plants were formed but pollen were not formed. Even though pollen were formed, they were all empty. 5. Hybrid plants were more winterhardy and summer persistency than Italian ryegrass. They showed a equivalent growth to Italian ryegrass in spring and to tall fescue in summer. 6. Chromosome of $F_1$-hybrids was allopolyploid(2n=4~=28) and all $F_1$-hybrid plants were sterile.

• 원예과학기술지
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• 제32권5호
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• pp.623-627
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• 2014

Curcuma alismatifolia 'Chiangmai Pink'의 화아발달 과정을 SEM을 통해 관찰하였다. 쿠르쿠마 근경에서 자란 맹아의 발육정도에 따른 화아분화 과정과 단계별 화아분화의 형태적 특성은 정식 후 식물체의 싹이 15-20cm 가량 자랐을때 생장점의 중앙부가 돔형으로 비대되는 경정분열조직에서 포엽이 분화되기 시작하였다. 포엽이 5-7매 가량 분화되면 포엽과 포엽 사이에서 화아가 형성되기 시작하였고, 보통 포엽당 화아는 4-6개가 관찰되었다. 화아가 분화되는 순서는 맨 하위 포엽 내 존재하는 것부터 상부로 올라가면서 하나씩 분화되었고 상부의 것이 분화되면 다시 하부의 4-6개의 화아 중 또 다른 화아가 상부쪽으로 향하면서 하나씩 순차적으로 되었다.

• 한국수정란이식학회지
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• 제25권4호
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• pp.237-245
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• 2010

Only an optimum number of viable spermatozoa in a frozen-thawed insemination dose can ensure conception at artificial insemination (AI). We report here the percentages of normal, abnormal and viable spermatozoa present in the frozen-thawed semen of 20 Black Bengal bucks used for commercial AI. Bucks in this experiment were of 19.3~46.1 months old and 25~42 kg body weight. Four semen straws (0.25 ml) from each buck were collected for evaluation of their kinetic parameters. Scrotal circumference was measured by using a scrotal tape, sperm motility was estimated on eye estimation and sperm concentration was determined by using a haemocytometer. Sperm morphology was studied in paraformaldehyde fixed spermatozoa under differential interference contrast (DIC) microscope. To determine the proportion of live (plasma membrane intact) spermatozoa, semen was stained with SYBR-14 and propidium iodide and examined under fluorescent microscope. Scrotal circumference, post-thaw sperm motility, sperm concentration per insemination dose and proportion of normal spermatozoa were $21.5{\pm}0.7\;cm$, $43.5 {\pm}5.4%$, $83.5{\pm}6.7$ million and $88.3{\pm}4.1%$, respectively. The percentages of spermatozoa with head shape and acrosome abnormalities were lower ($2.7{\pm}1.1$ and $1.4{\pm}1.3$, respectively), whereas higher percentages of abnormalities ($7.0{\pm}1.8$) were observed in mid piece and tail portion. The proportion of live spermatozoa was $28.5{\pm}5.4$. It is concluded that although a good number of morphologically normal spermatozoa are present in the insemination dose, the proportion of live spermatozoa is low, which warrants further improvements of buck semen freezing procedures to ensure good quality at AI.