• Clinical and Experimental Reproductive Medicine
• /
• v.34 no.3
• /
• pp.197-205
• /
• 2007

Objective: This study evaluated the pregnancy and implantation rates in fresh IVF-ET cycles or frozen-thawed ET (F-ET) cycles based on serum estradiol concentrations of controlled ovarian hyperstimulation (COH). Methods: Clinical outcomes of 1,565 cycles of fresh IVF-ET with COH and 670 cycles of F-ET were retrospectively analyzed. Serum estradiol levels on the day of human chorionic gonadotropin (hCG) administration were categorized into Group-A (1,000$\sim$2,000 pg/ml), Group-B (2,000$\sim$3,000 pg/ml), Group-C (3,000$\sim$4,000 pg/ml) and Group-D (> 4,000 pg/ml). Clinical pregnancy (CPR), implantation (IR) and delivery rates (DR) were compared among four groups subdivided into younger (< 35 years) and older ($\geq$ 35 years) women. Statistical analysis was performed by Student's t-test and chi-square test. Results: Overall clinical outcomes with fresh IVF-ET and F-ET cycles were similar: 41.2% vs 44.8% of CPR, 18.8% vs 19.6% of JR, and 33.2% vs 34.5% of DR, respectively. There were no significant differences in the clinical outcomes of all four groups between fresh IVF-ET and F-ET cycles of younger women according to the estradiol levels. However, the clinical outcomes of F-ET cycles of older women in Group-D were significantly higher than those of fresh IVF-ET cycles (51.3% vs 25.0% of CPR*, 18.6% vs 9.9% of IR and 33.3% vs 19.4% of DR;* p<0.05). Conclusion: Our results demonstrated that supraphysiological levels of estradiol during COH in fresh IVF-ET cycles of older women ($\geq$ 35 years) may be detrimental to implantation environments of endometrium and clinical outcomes, which could be improved by F-ET cycles.

• Applied Biological Chemistry
• /
• v.46 no.3
• /
• pp.171-175
• /
• 2003

The putative endochitinase gene, yheB of Escherichia coli K-12 is not expressed under lab culture conditions. The endochitinase gene was amplified by PCR and subcloned into pET28c vector and pQE9 vector, respectively. The endochitinase produced in E. coli harboring pET28c containing yheB or pQE9 vector containing yheE was partly released into the growth medium. The overproduced endochitinase was partially purified by His affinity column chromatography and DE-52 column chromatography. The apparent molecular weight of the endochitinase determined by SDS-polyacrylamide gel electrophoresis was about 97,000. The purified E. coli endochitinase showed maximal chitinolytic activity at pH 6 and $40^{\circ}C$.

• Journal of The Korean Astronomical Society
• /
• v.34 no.4
• /
• pp.309-311
• /
• 2001

Strong thermal X-ray emission, called Galactic Ridge X-ray Emission, is observed along the Galactic plane (Koyama et al. 1986). The origin of hot ($\~$7 keV) component of GRXE is not known, while cool ($\~$0.8 keV) one is associated with supernovae (Kaneda et al. 1997, Sugizaki et al. 2001). We propose a possible mechanism to explain the origin; locally strong magnetic fields of $B_{local}\;\~30{\mu}G$ heat interstellar gas to $\~$7 keV via magnetic reconnection (Tanuma et al. 1999). There will be the small-scale (< 10 pc) strong magnetic fields, which can be observed as $(B)_{obs} \;\~3{\mu}G$ by integration of Faraday Rotation Measure, if it is localized by a volume filling factor of f $\~$ 0.1. In order to examine this model, we solved three-dimensional (3D) resistive magnetohydrodynamic (MHD) equations numerically to examine the magnetic reconnect ion triggered by a supernova shock (fig.l). We assume that the magnetic field is Bx = 30tanh(y/20pc) $\mu$G, By = Bz = 0, and the temperature is uniform, at the initial condition. We put a supernova explosion outside the current sheet. The supernova-shock, as a result, triggers the magnetic reconnect ion, and the gas is heatd to > 7 keV. The magnetic reconnect ion heats the interstellar gas to $\~$7 keV in the Galactic plane, if it occurs in the locally strong magnetic fields of $B_{local}\;\~30{\mu}G$. The heated plasma is confined by the magnetic field for $\~10^{5.5} yr$. The required interval of the magnetic reconnect ions (triggered by anything) is $\~$1 - 10 yr. The magnetic reconnect ion will explain the origin of X-rays from the Galactic ridge, furthermore the Galactic halo, and clusters of galaxies.

• Korean Journal of Medicinal Crop Science
• /
• v.14 no.1
• /
• pp.14-18
• /
• 2006

This study was carried out to investigate the distribution and habitat characteristics of Boehmeria for utilization and conservation plan of natural agro-plant resources in South Korea. The native habitat of B. longispica Steud., B. platanifolia Fr. et Sav., B. spicata Thunb., and B. tricuspis var. unicuspis Mak. were distributed nearly all areas in South Korea. B. nivea Gaudich. was distributed south of Chungnam but B. pannosa Nak. et Sat. and B. sieboldiana Bl. were partially distributed toward the southern part in South Korea. The average number of plant species growing with Boehmeria in natural habitat was found 124.9 species and Artemisia princeps var. orientalis Hara showed the highest importance value among neighbor species. B. platanifolia Fr. et Sav. and B. spicata Thunb. were the most commonly neighbor species growing with Boehmeria in rate of 49%. Average yearly precipitation and temperature of habitat for Boehmeria were 1100 mm to 1390 mm and $11.3^{\circ}C\;to\;13.7^{\circ}C$ respectively. Soil characteristics of habitat for Boehmeria. were that pH was 5.3 to 7.2 and B. nivea Gaudich. was higher content of organic matter than the other Boehmeria. Content of K and Na were similar among Boehmeria. $P_2O_5$, Ca and Mg were shown a little difference among seven species.

• The Bulletin of The Korean Astronomical Society
• /
• v.37 no.1
• /
• pp.77.1-77.1
• /
• 2012

We present high-resolution radial velocity measurements of K2 giant ${\varepsilon}$ CrB from February 2005 to January 2012 using the fiber-fed Bohyunsan Observatory Echelle Spectrograph at Bohyunsan Optical Astronomy Observatory. We find that the RV measurements for ${\varepsilon}$ CrB exhibit a periodic variation of 418 days with a semi-amplitude of 129 m/s. There is no correlation with RV measurements and inhomogeneous surface features by examining chromospheric activity indicator (Ca II H region), the Hipparcos photometry, and bisector velocity span. Thus, Keplerian motion is the most likely explanation, which suggests that the RV variations arise from an orbital motion. Assuming a possible stellar mass of 1.7 $M_{\odot}$, for ${\varepsilon}$ CrB, we obtain a minimum mass for the planetary companion of 6.7 $M_{Jup}$ with an orbital semi-major axis of 1.3 AU, and an eccentricity of 0.11. We support that more massive stars harbor more massive planetary companions in giant hosting planetary companions (Dollinger et al. 2009), as well as, we discuss the frequency of detected planetary companions with the metallicity distribution in giant (Pasquini et al. 2007; Quirrenbach et al. 2011).

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.32 no.3
• /
• pp.235-240
• /
• 1996

Forecasts of monthly landings of walleye pollock, Theragra chalcogramma, in Korea were carried out by the seasonal Autoregressive Integrated Moving Average(ARlMA) model. The Box - Cox transformation on the walleye pollock catch data handles nonstationary variance. The equation of Box - Cox transformation was Y'=($Y^0.31$_ 1)/0.31. The model identification was determined by minimum AIC(Akaike Information Criteria). And the seasonal ARlMA model is presented (1- O.583B)(1- $B^1$)(l- $B^12$)$Z_t$ =(l- O.912B)(1- O.732$B^12$)et where: $Z_t$=value at month t ; $B^p$ is a backward shift operator, that is, $B^p$$Z_t$=$Z_t$-P; and et= error term at month t, which is to forecast 24 months ahead the walleye pollock landings in Korea. Monthly forecasts of the walleye pollock landings for 1993~ 1994, which were compared with the actual landings, had an absolute percentage error(APE) range of 20.2-226.1 %. Thtal observed annual landings in 1993 and 1994 were 16, 61OM/T and 1O, 748M/T respectively, while the model predicted 10, 7 48M/T and 8, 203M/T(APE 37.0% and 23.7%, respectively).

• Journal of Plant Biology
• /
• v.4 no.2
• /
• pp.41-50
• /
• 1961

1. This study was made on the flora of mosses on Mt. Chi I(127$^{\circ}$26'-35' E.Long, 35$^{\circ}$12'-25' N.Lat). 2. In the list of mosses of Mt. Chi I, 126 species, 6 varieties, and 1 form belonging to 79 genera are enumerated. Of these the following 14 taxa are new to the Korean flora. (1) Fhabdoweissia fugat(Hedw.) B.S.G. (2) Pohlia crudoides(Sull. et Lesq.) Broth var. revolvens(Card.) Ochi (3) Philonotis socia Mitt. (4) Ptychomitrium linearifolium Rms. (5) Ulota crispa Brid. (6) Neckera konoi Broth. (7) Neckeroptsis nitidula(Mitt.) Fleisch. (8) Entodon fauriei Broth. et Par. (9) Plagiothecium denticulatum (Hedw.) B.S.G. (10) Hypnum hamulosum B.S.G. (11) H. sakuraii var. venustum Ando. (12) H. tristoviride var. brevisetum Ando. (13) Gollania varians (Mitt.) Broth. (14) Pogonatum pygmaeum Card

• The Korean Journal of Ecology
• /
• v.9 no.4
• /
• pp.209-223
• /
• 1986

The forest stands of Seonusan area, South-western Korea, were classified into three alliances and nine communities by the Z-M school scheme. Of these one alliance and four association were recognized in this study, that is, an alliance, Carpinion laxiflorae and four associations, Casrpinetum tschonoskii, Quercetum variabilis, Carpinetum laxiflorae and Rhododendro mucronulati-Pinetum densiflorae. Hierachy of Seonunsan area forest vegetation by Z-M scheme was as fallows: Pinion densiflorae Suz.-Tok. 1966. 1. Rhododendro mucronlati-Pinetum densiflorae ass.l nov., 2. Pinus thunbergii community. Carpinion laxiflorae all. nov., 1. Quercus serrata-Carpinus tschonoskii community, 2. Quercus aliena-Carpinus tschonoskii community, 3, Carp inetum tschonoskii ass. nov., a. Typical subass., b. Sasa borealis subass. 4. Quercetum variabilis ass. nov., a Sasa borealis subass. b. Typical subass, 5. Carpinetum laxiflorae ass. nov., Zelkovion serratae Miyawaki et al., 1977., 1. Orixo-Zelk ovetum serratae Miyawaki et H. Tohma 1975., a Typical subass., b. Thea sinensis facies, 2. Thea sinensis-Camellia japonica community.

• Journal of the Korean Chemical Society
• /
• v.67 no.2
• /
• pp.150-155
• /
• 2023

Eurya emarginata is an evergreen tree growing in the southern regions of Korea including Jeju Island. In this study, antioxidant and anti-photoaging effects were investigated with the extracts of E. emarginata leaves. As comparative studies with the extract and five solvent fractions, the EtOAc fraction showed the most effective DPPH and ABTS⁺ radical scavenging activities. The EtOAc fraction also inhibited matrix metalloproteinase-1 (MMP-1) production most effectively. Phytochemical study on the EtOAC fraction resulted in the isolation of three compounds; eutigoside C (1), eutigoside B (2) and quercitrin (3). Among the isolates (1-3), quercitrin (3) showed excellent antioxidant activities and inhibitory properties on MMP-1 production. Based on these results, it was suggested that extracts of E. emarginata leaves could be developed as natural anti-photoaging agents in cosmetic formulations.

• Clinical and Experimental Reproductive Medicine
• /
• v.43 no.3
• /
• pp.181-184
• /
• 2016

The aim was to report a healthy live birth using re-vitrified-warmed cleavage-stage embryos derived from supernumerary warmed embryos after frozen embryo transfer (ET) in a patient with recurrent implantation failure (RIF). The case was a 39-year-old female with a history of polycystic ovarian syndrome and adenomyosis, along with RIF. After ovarian hyperstimulation, 33 cumulus-oocyte complexes were retrieved and fertilized with conventional in vitro fertilization and intracytoplasmic sperm injection. Because of the risk of ovarian hyperstimulation syndrome, 16 grade B and C embryos were vitrified. After 3 and 6 months, 3 and 4 B-C warmed embryos were transferred to the uterus, respectively. However, implantation did not take place. Ten months later, four embryos were warmed, two grade B 8-cell embryos were transferred, and two embryos were re-vitrified. One year later, the two re-vitrified cleavage-stage embryos were warmed, which resulted in a successful live birth. This finding showed that following first warming, it is feasible to refreeze supernumerary warmed embryos for subsequent ET in patients with a history of RIF.