• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.2
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• pp.227-234
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• 2015

To obtain geographical range and growth-kinetics parameters of mottled sake (Beringraja pulchra) populations in the Yellow Sea, three mark-recapture experiments were carried out. Overall, 991 tagged individuals were released, and 4.1% of them were recaptured with the mean release period of 339 d (range, 8-1,420 d) and the mean growth rate of $1.4cm\;mon^{-1}$ (female, $1.5cm\;mon^{-1}$; male $1.3cm\;mon^{-1}$). In the first experiment, 667 individuals were released at Heuksan Island from April to June, 2007-2009, and 30 individuals were recaptured mainly at the north and the north-east coasts of the island, indicating absence of migration to the south of the island. In the second experiment, 323 individuals were released at several fishing grounds scattered in the Yellow Sea in 2010-2013, and 11 individuals were recaptured at points deviated to all directions from the releasing points. As the last, one individual was released with pop-up satellite archival tag at a costal point ($34^{\circ}37.2$'N, $124^{\circ}59.3$'E) off Hong Island on May 21, 2010. The tagged individual migrated to a north-east location ($35^{\circ}50.4$'N, $126^{\circ}03.6$'E) of Eocheong Island by Aug. 25, 2010. The data archived for the three months in the tag indicated that the migration path had depths of 48-80 m and temperature of $12.6-14.4^{\circ}C$. The results indicated that mottled sake populations had a localized habitat ranges at the north of Heuksan Island and the west of Hong Island while growing at the rate of $1.4cm\;mon^{-1}$.

• The korean journal of orthodontics
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• v.25 no.2 s.49
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• pp.187-200
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• 1995

To estimate the characteristics of Korean Ni-Ti alloy orthodontic wire, this study investigated compositions, tensile properties, bending properties, heat treatment effects, and ion releasing degrees, and compared these characteristics to those of the imported Ni-Ti alloy wire. The results obtained are as follows ; 1. Ti and -Ni elements in ORTHOLLOY were in a range showing superelasticity, and there was a little difference in the Ni and Ti contents of ORTHOLLOY as compared with those of SENTALLOY. 2. The results of the tensile test concerning ORTHOLLOY exhibited a superelastic effect, indicating an area of a definite amount of stress in spite of the changes in the range from $2\%\;to\;8\%$ in the strain rate. 3. ORTHOLLOY presented higher load values than SENTALLOY in the same deflection values when the wire was tested in three-point bending. A load range displaying a superelastic effect was 80-l00g, 140-l80g, and 130-200g respectively, in wire diameters of 0.014', 0.016', and 0.018' 4. By heat treatments at $400^{\circ}C$ and at $500^{\circ}C$, a load range showing the effect of superelasticitly was lessened by the duration of the heat treatment time. The superelastic effect was destroyed as a result of the 10 minutes heat treatment at $600^{\circ}C$. 5. The quantity of the Ni ion released from ORTHOLLOY, tended to be greater than the amount of released Ni ion in SENTALLOY. The Co ion released was very little(<0.01ppm) in SENTALLOY and ORTHOLLOY irrespective of the lapse of time. Released Ni ions on the 1st day were at the maximum, and the releasing rate showed plateaus after three days. 6. The surface morphology of SENTALLOY was relatively regular irrespective of the lapse of rime, and the corrosion tendency was not observed. However, the surface morphology of ORTHOLLOY was rather irregular and shelved fitting corrosion after immersion.

• Clinical and Experimental Reproductive Medicine
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• v.42 no.2
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• pp.62-66
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• 2015

Objective: To evaluate the effect of a gonadotropin-releasing hormone (GnRH) antagonist protocol using corifollitropin alfa in women undergoing assisted reproduction. Methods: Six hundred and eighty-six in vitro fertilization-embryo transfer (IVF)/ intracytoplasmic sperm injection (ICSI) cycles were analyzed. In 113 cycles, folliculogenesis was induced with corifollitropin alfa and recombinant follicle stimulating hormone (rFSH), and premature luteinizing hormone (LH) surges were prevented with a GnRH antagonist. In the control group (573 cycles), premature LH surges were prevented with GnRH agonist injection from the midluteal phase of the preceding cycle, and ovarian stimulation was started with rFSH. The treatment duration, quality of oocytes and embryos, number of embryo transfer (ET) cancelled cycles, risk of ovarian hyperstimulation syndrome (OHSS), and the chemical pregnancy rate were evaluated in the two ovarian stimulation protocols. Results: There were no significant differences in age and infertility factors between treatment groups. The treatment duration was shorter in the corifollitropin alfa group than in the control group. Although not statistically significant, the mean numbers of matured (86.8% vs. 85.1%) and fertilized oocytes (84.2% vs. 83.1%), good embryos (62.4% vs. 60.3%), and chemical pregnancy rates (47.2% vs. 46.8%) were slightly higher in the corifollitropin alfa group than in the control group. In contrast, rates of ET cancelled cycles and the OHSS risk were slightly lower in the corifollitropin alfa group (6.2% and 2.7%) than in the control group (8.2% and 3.5%), although these differences were also not statistically significant. Conclusion: Although no significant differences were observed, the use of corifollitropin alfa seems to offer some advantages to patients because of its short treatment duration, safety, lower ET cancellation rate and reduced risk of OHSS.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.6
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• pp.717-729
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• 1999

Although many studies on the cytotoxicity of the dental cast base metal alloys and their components have been carried out, the results are rather conflicting because of the different type of cells used and the various experimental procedures taken. Recently a number of scientists have claimed that it would be preferable to focus on the use of cells from relevant specific location of the human bodies. Consequently, the primary cultured oral keratinocyte derived from oral mucous along with nickel chloride and several of widely used dental cast base metal alloys(two Ni-Cr alloys and one Co-Cr alloy)in domestic were selected for this study, from which 1) The amounts of released metal ions were determined using atomic absorption spectrometry, 2) The cytotoxicity of nickel chloride and dental cast base metal alloys was evaluated via MTT assay, and finally, 3) The amounts of released metal ions and the cytotoxicity of nickel chloride were correlated with the cytotoxicity of dental cast base metal alloys And, the results were summarized as follows; 1. Nickel ion from Ni-Cr alloys and Cobalt ion from Co-Cr alloys resulted in maximum releasing rate during first 2h hours, followed by a decrease in releasing rate with time. Chromium ion were found to be minimal in all alloys. 2. In cytotoxic test. with $40{\mu}M,\;80{\mu}M$ of nickel chloride, there were observed an increase in the relative cell number compared to control samples after 24 hours. With $160{\mu}M$, there was found to be no difference in the relative cell number with control, except that 48 hour showed a increase in relative cell number. With $320{\mu}M$, the relative cell number remained constant and decreased after 48 hours, and with $640{\mu}M$, a continuing decrease in relative cell number was observed throughout test period. 3 The sensitivity of primary cultured oral epithelium to nickel was lower compared to the cells used in other studies. 4. CB-80 Soft and Regalloy showed no cytotoxicity to primary cultured oral epithelium and New crown resulted in a slight cytotoxicity. In conclusion, it was shown that the primary cultured oral keratinocytes could be applied successfully as testing cells in cytotoxicity test. Futhermore, the dental cast base metal alloys used in this study were found to be biocompatible.

• Clinical and Experimental Reproductive Medicine
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• v.25 no.1
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• pp.43-50
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• 1998

This study was performed to determine the effects of nitric oxide on human sperm cell function. Semen samples were obtained from normal healthy volunteers. Motile spermatozoas collected by swim-up method were incubated up to 24 hours in Ham's F-10 medium supplemented with a various concentration of sodium nitroprusside (nitric oxide releasing agent). Sperm motility, hyperactivation, acrosome reaction rate, and acrosin activity were determined. The results are as follows; 1. 1mM of SNP resulted in a significant decrease in sperm motility ($44.8%{\pm}8.9%:78.1%{\pm}6.3%$, and hyperactivation $(10.4%{\pm}6.4%:47.7%:{\pm}9.5%)$ after incubation for 3 hours compared with the control group (Ham's F-10 alone), but had no effect on acrosome reaction. 2. At $100{\mu}M$ SNP, sperm motility was reduced after incubation for 6 hours $(54.8%{\pm}3.2%)$ compared with that of the control group $(82.7%{\pm}8.9%)$, but hyperactivation and acrosome reaction were not affected. 3. However, a lower concentration (less than $10{\mu}M$) of SNP had no effect on sperm motility and hyperactivation for 8 hours of incubation but significantly decreased them when incubation periods were increased up to 24 hours compared with the control group. On the other hand, $1{\mu}M$ and $10{\mu}M$ SNP significantly increased the acrosome reaction rate in both acrosomal status ($17.3%{\pm}5.2%$, $23.5%{\pm}4.7%$, respectively) and acrosin activity ($34.3{\mu}IU{\pm}10.5{\mu}IU,\;45.6{\mu}IU{\pm}5.6{\mu}IU$, respectively) as compared with the control group $(7.0%{\pm}4.0%,\;9.5{\mu}IU{\pm}3.4{\mu}IU)$. These results indicate that SNP, NO releasing agent, has a dose-dependent effects on the sperm cell function. Therefore it may positively affect the fertilization by promoting acrosomal reaction at a lower concentration (less than $10{\mu}M$).

• Clinical and Experimental Reproductive Medicine
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• v.37 no.3
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• pp.239-244
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• 2010

Objective: The objective of this retrospective study was to compare the in vitro fertilization (IVF) outcomes of gonadotropinreleasing hormone (GnRH) agonist and GnRH antagonist protocols in poor responders. Methods: A total of 172 cycles in subjects with less than 5 oocytes retrieved treated with either GnRH agonist long protocols or antagonist protocols were included. The outcome variables such as numbers of growing follicles and retrieved oocytes, and the fertilization rate were evaluated as the main outcome measures. Results: There was no difference in regard to the numbers of growing follicles and oocytes, and fertilization rate between the two groups. $E_2$ level on Day 7/8, mean gonadotropin dose, and the days of stimulation were shown to be statistically different (p<0.01, respectively). Conclusion: Considering that similar results were observed with less time and gonadotropin dose, GnRH antagonist protocol may be considered as a preferable choice over GnRH agonist protocols in poor responders.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.2
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• pp.92-97
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• 2008

Salt wedge into the river from the sea or fresh water flume (fresh wedge) in the ocean from the sea has density current characteristics. However, when temperature and salinity simultaneously determine the density of wedges, one of salinity and temperature can distributed in the reversed profiles against gravity, even though the density profile is stable. In this case, the double diffusive process is critical in determining mixing rate. The present work studies relative contribution of shear driven mechanical mixing component and double diffusive layering process, when warm salty denser water is introduced into the cold fresh lighter water column. Laboratory experiment releases warm salty denser water into cold fresh lighter water controlling discharge amount to achieve the steady state of density current. When longitudinal density rate becomes 15, the released amount ratio of salt and heat changes sharply and in the releasing point, vigorous mixing occurs with increase of discharged amount due to double diffusion. Double diffusion distabilizes gravitational stability and enhances the mixing rate up to $6{\times}10$ times at the lower density ratio comparing to the higher density ratio.

• Clinical and Experimental Reproductive Medicine
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• v.21 no.1
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• pp.13-20
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• 1994

Status of endometrium is a very important factor which influences the implantation of fertilized embryos. In this study, we evaluated the possibility that the endometrial depth and pattern assessed by vaginal sonography on the day of human chorionic gonadotropin (HCG) injection in in vitro fertilization (IVF) cycles could be used to predict the IVF outcome. A total of 112 cycles using gonadotropin releasing hormone agonist (GnRHa) for ovulation induction were evaluated. We classified all patients into group A(<9mm) or group B(${\geq}$ 9mm) according to endometrial depth, and into group l(hyperechogenic), group 2(isoechogenic) or group 3(hypoechogenic and triple line) according to endometrial pattern. The other classification was made considering both endometrial depth and pattern. There was no significant correlation between serum estradiol level and endometrial sonographic findings(depth and pattern)(p>0.05). The pregnancy rate of group A(31.3%) did not differ significantly from that of group B(43.7%), but no pregnancies were found in any patients with endometrial depth less than 6mm. The pregnancy rate was 40%, 35.7%, and 44.6 % for group 1, gorup 2, and group 3, respectively, but there was no statistically significant difference between these groups(p>0.05). In combined classification, there was a trend of higher pregnancy rate in case of endometrial depth greater than 9mm and hypoechogenic triple line pattern, but there was no statistically significant differences between these groups(p>0.05). The conclusion from the present data is that endometrial ultrasonography on the day of hCG administration had no predictive value for conception in IVF cycles.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.11
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• pp.821-826
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• 2013

The purposes of this research are to study on optimal distance between positive and negative electrodes in dust removal chamber. The experiments were performed with electrode-plate gab arranging in order of 3 cm, 2 cm, 1 cm in series while varying influent flow-rate. From the experimental results of dust removal the optimal influent linear velocity was 6 cm/sec and the total mass of attached dust on the surface of electrode-plate was increased as electrode-plate gab is closer. But in case of electrode-plate gab being very close about 1 cm or so, the attached dust on the surface of electrode-plate was shown releasing from electrode-plate due to dust electric-charge changing (reverse ionization). Evantually. optimal distance between positive and negative electrode-plates was about 2 cm and also optimal dust loading rate was about $24mg/min{\cdot}m^2$.

• Analytical Science and Technology
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• v.23 no.3
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• pp.255-260
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• 2010

The Ministry of Environment simultaneously revised testing methods and emission standards of adhesives product on the "Law of indoor air quality management" for the effective management of the building materials releasing pollutants in great quantities. Accordingly, it is impossible to compare original standards with revised standards directly. The influences of each factor of the revised testing methods of adhesive product on the emission rate of pollutants are reviewed through comparing with the original testing method. Through this study, revised pollutant emission control standards were assessed. With the result that it is found that emission rate of adhesives product is weakened two and half times by changing test period and the emission rate resulting from changing drying time has little difference. As a result of comparing TVOC emission standards with the original testing method considering the modification of testing methods, it is found that the emission standard through this revision is strengthened about 2.1 times more than that of present testing method.