• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.41 no.4
• /
• pp.257-262
• /
• 2017

As the size of electric products such as mobile phones and smart watches decrease, the bolts used to assemble these products should also be miniaturized. A miniature-sized bolt has to provide sufficient joining torque and anti-releasing torque to keep the components together. We studied a serrated bolt as a candidate for a miniature-sized fastener to increase the anti-releasing torque. In a serrated bolt, a serrated shape is formed on the bottom surface of the bolt head to create an obstacle to releasing. In this study, finite element analyses for the joining and releasing of bolts were carried out, and the anti-releasing performance was predicted. Based on the results of analyses using various numbers of serrations and fastening depths, the effects of the number of serrations and fastening depth on the anti-releasing performance were investigated.

• Journal of Veterinary Clinics
• /
• v.23 no.3
• /
• pp.325-328
• /
• 2006

A 10-year-old intact female Miniature Schnauzer dog was referred with the primary complaint of persistent anorexia, remittent fever, vomiting and abdominal pain. Hemogram suggested a chronic inflammatory disease. Serum biochemistry showed moderate hepatobiliary cellular damage with severe cholestasis. Abdominal radiography and ultrasonography revealed hepatomegaly, choleliths and sludges in gall bladder and small stones in urinary bladder. Based on diagnostic findings, the case was diagnosed as cholelithiasis complicated with biliary sludge and urolithiais. Using cholecystectomy and cystectomy, choleliths and uroliths were removed from gall bladder and urinary bladder, respectively. The clinical condition was dramatically improved after surgery.

• Reproductive and Developmental Biology
• /
• v.38 no.3
• /
• pp.99-105
• /
• 2014

In this study, to further understand the mechanism of animal growth and to develop a miniature transgenic animal model, we constructed and tested tetracycline-inducible RNAi system using shRNA targeting the mRNA of mouse insulin-like growth factor (mIGF-1) or mouse growth hormone receptor (mGHR) gene. Quantitative real-time PCR analysis of mouse liver cell (Hepa1c1c7) cells transfected with these vectors showed 85% or 90% of expression inhibition effect of IGF-1 or GHR, respectively. In ELISA analysis, the protein level of IGF-1 in the cells expressing the shRNA targeting IGF-1 mRNA was reduced to 26% of non-transformed control cells. Unexpectedly, in case of using shRNA targeting GHR, the IGF-1 protein level was decreased to 75% of control cells. Further experiments are needed to explain the lower interference effect of GHR shRNA in IGF-1 protein. Accumulated knowledge of this approach could be applicable to a variety of related biological area including gene function study, gene therapy, development of miniature animals, etc.

• Journal of Embryo Transfer
• /
• v.31 no.4
• /
• pp.355-365
• /
• 2016

The cryopreservation of sperm has become the subject of research for successful artificial insemination technologies. Antifreeze proteins (AFPs), one of the factors necessary for effective cryopreservation, are derived from certain Antarctic organisms. These proteins decrease the freezing point of water within these organisms to below the temperature of the surrounding seawater to protect the organism from cold shock. Accordingly, a recent study found that AFPs can increase the motility and viability of spermatozoa during cryopreservation. To evaluate this relationship, we performed cryopreservation of boar sperm with AFPs produced in the Arctic yeast Leucosporidium sp. AFP expression system at four concentrations (0, 0.01, 0.1, and $1{\mu}g/ml$) and evaluated motility using computer assisted sperm analysis. DNA damage to boar spermatozoa was measured by the comet assay, and sperm membrane integrity and acrosome integrity were evaluated by flow cytometry. The results showed that motility was positively affected by the addition of AFP at each concentration except $1{\mu}g/ml$ (p<0.001). Although cryopreservation with AFP decreased the viability of the boar sperm using, the tail DNA analyses showed that there was no significant difference between the control and the addition of 0.1 or $0.01{\mu}g/ml$ AFP. In addition, the percentage of live sperm with intact acrosomes showed the least significant difference between the control and $0.1{\mu}g/ml$ AFP (p<0.05), but increased with $1{\mu}g/ml$ AFP (p<0.001). Our results indicate that the addition of AFP during boar sperm cryopreservation can improve viability and acrosome integrity after thawing.

• Reproductive and Developmental Biology
• /
• v.37 no.1
• /
• pp.1-8
• /
• 2013

In order to investigate genetic stability and gene expression profile after cloning procedure, two groups of cloned pigs were used for swine leukocyte antigen (SLA) gene nucleotide alteration and microarray analyses. Each group was consist of cloned pigs derived from same cell line (n=3 and 4, respectively). Six SLA loci were analyzed for cDNA sequences and protein translations. In total, 16 SLA alleles were identified and there were no evidence of SLA nucleotide alteration. All SLA sequences and protein translations were identical among the each pig in the same group. On the other hand, microarray assay was performed for profiling gene expression of the cloned pigs. In total, 43,603 genes were analyzed and 2,150~4,300 reliably hybridized spots on the each chip were selected for further analysis. Even though the cloned pigs in the same group had identical genetic background, 18.6~47.3% of analyzed genes were differentially expressed in between each cloned pigs. Furthermore, on gene clustering analysis, some cloned pigs showed abnormal physiological phenotypes such as inflammation, cancer or cardiomyopathy. We assumed that individual environmental adaption, sociality and rank in the pen might have induced these different phenotypes. In conclusion, the results of the present study indicate that SLA locus genes appear to be stable following SCNT. However, gene expressions and phenotypes between cloned pigs derived from the same cell line were not identical even under the same rearing conditions.

• Nuclear Engineering and Technology
• /
• v.48 no.3
• /
• pp.673-683
• /
• 2016

This paper analyzes the accuracy of the methods used in calibrating the thermal power of Nigeria Research Reactor-1 (NIRR-1), a low-power miniature neutron source reactor located at the Centre for Energy Research and Training, Ahmadu Bello University, Zaria, Nigeria. The calibration was performed at three different power levels: low power (3.6 kW), half power (15 kW), and full power (30 kW). Two methods were used in the calibration, namely, slope and heat balance methods. The thermal power obtained by the heat balance method at low power, half power, and full power was $3.7{\pm}0.2kW$, $15.2{\pm}1.2kW$, and $30.7{\pm}2.5kW$, respectively. The thermal power obtained by the slope method at half power and full power was $15.8{\pm}0.7kW$ and $30.2{\pm}1.5kW$, respectively. It was observed that the slope method is more accurate with deviations of 4% and 5% for calibrations at half and full power, respectively, although the linear fit (slope method) on average temperature-rising rates during the thermal power calibration procedure at low power (3.6 kW) is not fitting. As such, the slope method of power calibration is not suitable at lower power for NIRR-1.

• Journal of Korea Society of Industrial Information Systems
• /
• v.11 no.5
• /
• pp.98-104
• /
• 2006

In this parer, proposed a Miniature inverted F Antenna for Bluetooth applications using folded structure and confirm it through producing and measurement. The proposed antenna as PIFA is optimized the impedance matching and the radiation pattern by positioning of feed line and short line. This antenna is designed with Microwave Studio presented CST and the optimized antenna structure is fabricated. The optimized miniature antenna size is 17.3 * 6 * 0.8 mm, the measured return loss bandwidth is 220MHz at 2.45GHz, the radiation pattern is quasi omni, and the gain is -1 dBi. these results are similar to the simulation data. It is comparatively appropriate for Bluetooth system.

• Journal of Wetlands Research
• /
• v.19 no.3
• /
• pp.303-310
• /
• 2017

This paper is to understand the settling properties of cohesive sediments under effects of ions in turbulent flow. The experiments were conducted using a miniature annular flume(mini flume) with a free water surface. Silica was used as sediment of experiment. The suspended concentrations were measured by using a CCD-Camera. Settling of silica($SiO_2$) was allowed to occur under various shear stresses in a concentration of 7g/L. At condition of pH 4.2 and high NaCl concentration, the floc size D of silica was larger than D at condition of pH6.8 with the bed shear stress increasing. The settling velocity $W_s$ of silica was higher at condition of 10g NaCl/L than $W_s$ at condition of pH4.2. Comparison of measured concentration-time curves and concentration-time curves calculated by this study showed similar tendency in flow under effects of ions.

• Journal of Veterinary Clinics
• /
• v.26 no.6
• /
• pp.603-605
• /
• 2009

A 7-year-old intact female, Miniature Schnauzer dog was presented with an acute seizure episode and tremors. Fever and panting were noted when presented. Physical examination revealed apparent forelimb muscle rigidity, fasciculations and stiff gait. Characteristic laboratory findings in this dog were severe hypocalcemia with hyperphosphatemia. The low serum concentration of intact parathyroid hormone and ionized calcium levels were consistent with the diagnosis of primary hypoparathyroidism. In addition, there were increased urinary excretion of calcium and decreased urinary excretion of phosphorus in this case. Urgent treatment was initiated with 10% calcium gluconate. The dog remained healthy with vitamin D analogue and oral calcium supplementation. A transient hyperphosphatemia was controlled well with sevelamer hydrochloride. To the author's knowledge, this is the first case report describing the clinical and laboratory characteristic features of canine primary hypoparathyroidism and its clinical outcome in Korea.

• Journal of Korea Foresty Energy
• /
• v.21 no.1
• /
• pp.32-40
• /
• 2002

This study was carried out to investigate the effects of rootball media and covering materials for air-layering on the rooting and growth responses of miniature tree material. The experiment was performed with Carpinus coreana Nakai in the vinyl-house condition. The covering material, jute tape increased the diameter growth at 1cm above the girdling part of the tree material. The combined use of the soil mixture of peatmoss and perlite(2:1, by volume) as rootball medium and jute tape increased the dry weight of current year leaves and shoots. The number of shoot shorter than 10cm and that of leaves from the shoot were produced more by using a sphagnum moss for rootball medium than the soil mixture. The use of jute tape shortened the period required for rooting and increased the number of fine roots and the total root dry weight at girdling part of the tree material. On the other hand, the number of long roots was produced more by using the sphagnum moss than the soil mixture.