• Biomedical Science Letters
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• v.19 no.3
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• pp.206-212
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• 2013

The herbal composition Gyeongshingangjeehwan 18 (GGEx18), which is composed of three herbs, Laminaria japonica Aresch (Laminariaceae), Rheum palmatum L. (Polygonaceae), and Ephedra sinica Stapf (Ephedraceae), has been used as an anti-obesity drug in Korean local clinics. Thus, we investigated whether GGEx18 regulates obesity by suppressing appetite in high fat diet-induced obese C57BL/6J mice. Administration of GGEx18 to obese mice for 9 weeks significantly decreased body weight gain, epididymal adipose tissue weight, and food efficiency ratio. GGEx18 also caused a significant decrease in the circulating levels of leptin, which were increased by about 450% in obese control mice compared with normal lean mice. Concomitantly, GGEx18 decreased mRNA levels of a potent appetite-stimulating hormone neuropeptide Y, but increased an appetite-suppressing hormone pro-opiomelanocortin mRNA levels. These results suggest that GGEx18 may prevent obesity through regulating appetite in nutritionally obese mice.

• JSTS:Journal of Semiconductor Technology and Science
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• v.4 no.1
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• pp.74-81
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• 2004

We propose a novel scheme to transmit high center frequency RF signals using electroabsorption devices (EADs) as frequency converters at the transmitter and the receiver. In this approach frequency heterodyning is employed for obtaining high center frequency. With the EAD as a detector/mixer at the receiver we demonstrated a smaller conversion loss than that of the conventional modulator/mixer. With EAD as a modulator/mixer at the transmitter and with two heterodyned lasers to generate an optical local oscillator (LO), we demonstrated a large reduction (${\sim}23dB$) in conversion loss, and the transmission is not limited by the optical saturation of the EAD. This transmission scheme has optical single-side-band transmission feature which greatly relieves the fiber dispersion effect.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.161-161
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• 1998

To achieve the aim of this investigation, the extracellular protease was isolated from bacteria BAC-4, a strain was cultivated in the medium for the production of penicillin acilase in a period of 32 hours. The enzyme was first purified by aceton precipitation method, followed by ion exchange chromatography on DEAE-sephacel column. The highest specific activity of the aceton fraction was found to be 2.19 unit per mg, with degree of purification of 13 times. Further purification of the enzyme on DEAE -sephacel had a specific activity of 58.6 unit per mg and degree of purification of 344 times compared to its crude extract. The optimum pH of the enzyme was 8.4, and the potimum temparature was 37$^{\circ}C$. The K$\_$M/ and $V_{max}$ calculated at experiment conditions were found to be 0.66%(W/V) and 3.61 unit per mL respectively.

• Korean Journal of Pharmacognosy
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• v.30 no.4
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• pp.397-403
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• 1999

Tyrosinase plays an important role in the process of melanin polymer biosynthesis. Therefore, the enzyme inhibitors have been of great concern as cosmetics to have skin-whitening effects on the local hyperpigmentation. During the search for new inhibitory compounds on melanin polymer biosynthesis from natural sources, MeOH extracts of 589 higher plants were tested for the inhibitory effect on tyrosinase activity by the muschroom tyrosinase assay in vitro. Among plants tested, the leaves of Cercis chinensis exhibited potent inhibitory effect on mushroom tyrosinase activity. Subsequently seven active compounds were isolated from the ethyl acetate soluble part of acetone extract of the leaves of C. chinensis by the activity guided fractionation monitoring the inhibitory effect on tyrosinase activity. Their chemical structures were identified as $kaempferol-3-0-{\alpha}-L-rhamnoside$, quercitrin, $myricetin-3-0-{\alpha}-L-rhamnoside$, myricetin-3-0-(2'-O-galloyl)- ${\alpha}$ -L-rhamopyranoside (desmanthin), (-)-epicatechin-3-0-gallate, (-)-epigallocatechin-3-0-gallate, and methyl gallate on the basis of the speculation of spectral data and chemical reaction. Among the flavonol rhamnosides, myricetin-3-0-(2'-O-galloyl)- -L-rhamnoside(desmanthin) showed most potent inhibitory effect on tyrosinase activity and the structure of B-ring in flavonol moiety was related to the activity. (-)-Epigallocatechin-3-O-gallate having pyrogallol group in flavan-3-ol moiety exhibited more potent inhibitory effect than (-)-epicatechin-3-0-gallate having catechol group in flavan-3-ol moiety on mushroom tyrosinase activity.

• Korean Journal of Plant Taxonomy
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• v.36 no.1
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• pp.61-89
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• 2006

Algific talus slopes are local cold micro-environmental habitats where cool air escapes through vents and fissures of talus layer, and ice forms in summer. To access the phytogeographical significance and to develop the conservation strategy on vegetation of the algific talus, plant species composition on seven algific talus in South Korea was investigated. As a results, phytogeographically significant northern elements such as Cystopteris fragilis (L.) Bernh., Diplazium sibiricum (Turcz. ex Kunze) Sa.Kurata, Polypodium virginianum L., Vaccinium vitis-idaea L. and Hackelia deflexa (Wahlenb.) Opiz were distributed in these algific talus slopes (below $N37^{\circ}43^{\prime}$). In addition, subalpine species such as Woodsia subcordata Turcz, Rosa suavis willd., Clematis fusca var. coreana ($H.L{\acute{e}}v.$ & Vaniot) Nakai, Calamagrostis langsdorfii (Link) Trin. and Carex vaginata var. petersii (C.A.Mey.) Akiyama were also distributed as typical relictual species of these algific talus (less than alt. 400m). The algific talus slopes in Korean peninsular can be regarded as the insular refugia that northern plant species advanced southward during the latest glacial age have been isolated and adapted in some local microhabitats. Because the algific talus slopes as paleorefugia are very important in terms of phytogeography as well as meteorology ans geology, developments of strategies for in situ and ex situ conservation on these small isolated and threatened populations associated with the algific talus urgently needed.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.171-177
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• 2012

We bred a mulberry cultivar named Sangberry, through local adaptability test, which is under registration as a new cultivar for fruit production. Local adaptability test had been carried out at four places(Suwon, Kongju, Jangseong and Sangju) for six years from 2005. This is tetraploidy variety belonging to(Morus alba L.) made by colchicine treatment on growing point of winter buds. Sangberry was high yielding cultivar in fruit productivity by 70% compared to control cultivar "Chungilppong(Morus alba L.)" for four years. Although Sangberry was a little lower in sugar content of mulberry fruits, it contains more bioactive materials like C3G, rutin and amino acids than Chungilppong. It is adaptable to every where except the places where cold damage and sclerotic disease happen frequently.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.30-30
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• 2022

Philippines is the second world supplier of coconut by-products. As its first major genomics project, the Philippine Genome Center program for Agriculture (PGC-Agriculture) took the challenge to sequence and assemble the whole coconut genome. The project aims to provide advance genetics tools for our collaborating coconut researchers while taking the opportunity to initiate local capacity. Combination of different NGS platforms was explored and the Philippine 'Catigan Green Dwarf' (CATD) variety was selected with the breeders to be the crop's reference genome. A high quality genome assembly of CATD was generated and used to characterize important genes of coconut towards the development of resilient and outstanding varieties especially for added high-value traits. The talk will present the significant results of the project as published in various papers including the first report of whole genome sequence of a dwarf coconut variety. Updates will include the challenges hurdled and specific applications such as gene mining for host insect resistance and screening for least damaged coconuts (thus potentially insect resistant varieties). Genome-wide DNA markers as published and genes related to coconut oil qualitative/quantitative traits will also be presented, including initial molecular/biochemical studies that support nutritional and medicinal claims. A web-based genome database is currently built for ease access and wider utility of these genomics tools. Indeed, a major milestone accomplished by the coconut genomics research team, which was facilitated with the all-out government support and strong collaboration among multidisciplinary experts and partnership with advance research institutes.

• Journal of the Chungcheong Mathematical Society
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• v.37 no.1
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• pp.27-40
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• 2024

In this paper, we consider the higher-order HartreeFock equations. The higher-order linear Schrödinger equation was introduced in [5] as the formal finite Taylor expansion of the pseudorelativistic linear Schrödinger equation. In [13], the authors established global-in-time Strichartz estimates for the linear higher-order equations which hold uniformly in the speed of light c ≥ 1 and as their applications they proved the convergence of higher-order Hartree-Fock equations to the corresponding pseudo-relativistic equation on arbitrary time interval as c goes to infinity when the Taylor expansion order is odd. To achieve this, they not only showed the existence of solutions in L² space but also proved that the solutions stay bounded uniformly in c. We address the remaining question on the convergence of higherorder Hartree-Fock equations when the Taylor expansion order is even. The distinguished feature from the odd case is that the group velocity of phase function would be vanishing when the size of frequency is comparable to c. Owing to this property, the kinetic energy of solutions is not coercive and only weaker Strichartz estimates compared to the odd case were obtained in [13]. Thus, we only manage to establish the existence of local solutions in H^s space for s > $\frac{1}{3}$ on a finite time interval [-T, T], however, the time interval does not depend on c and the solutions are bounded uniformly in c. In addition, we provide the convergence result of higher-order Hartree-Fock equations to the pseudo-relativistic equation with the same convergence rate as the odd case, which holds on [-T, T].

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.73-73
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• 2003

We report here the results on N-acetyl-N'-methylamide of alanine (Ac-Ala-NHMe) calculated using the ab initio molecular orbital method with the self-consistent reaction field (SCRF) theory at the HF level with the 6-3l+G(d) basis set to investigate the conformational preference of alanine depending on the backbone torsion angles $\square$ and$\square$ in the gas phase, chloroform, and water. There are seven local minima (LM) in the gas phase and two additional LM are found in chloroform and water. These two additional LM A (an $\square$-helical structure) and F (a polyproline structure) are stabilized only in solutions. In the gas phase, the lowest LM is the conformation C with a C$\sub$7/ intramolecular hydrogen bond and the relative conformational energies range from 0.3 to 6.0 ㎉/mol. In chloroform, the lowest LM is the conformation E (an extended structure) and the relative conformational energies range from 0.7 to 4.9 ㎉/mol. In particular, we identified 14 possible transition states connecting between seven LM in the gas phase. The search for transition states probable in chloroform and water is now in progress.

• The Korean Journal of Pain
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• v.24 no.1
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• pp.31-35
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• 2011

Background: Circumcision is a painful intervention frequently performed in pediatric surgery. We aim to compare the efficacy of caudal block versus dorsal penile block (DPNB) under general anesthesia for children undergoing circumcision. Methods: This study was performed between July 1, 2009 and October 16, 2009. Fifty male children American Society of Anesthesiolgists physical status classification I, aged between 3 and 12 were included in this randomized, prospective, comparative study. Anesthetic techniques were standardized for all children. Patients were randomized into 2 groups. Using 0.25% 0.5 ml/kg levobupivacain, we performed DPNB for Group 1 and caudal block for Group 2. Postoperative analgesia was evaluated for six hours with the Flacc Pain Scale for five categories; (F) Face, (L) Legs, (A) Activity, (C) Cry, and (C) Consolability. For every child, supplemental analgesic amounts, times, and probable local or systemic complications were recorded. Results: No significant difference between the groups (P > 0.05) was found in mean age, body weight, anesthesia duration, FLACC pain, and sedation scores (P > 0.05). However, on subsequent measurements, a significant decrease of pain and sedation scores was noted in both the DPNB group and the caudal block group (P < 0.001). No major complication was found when using either technique. Conclusions: DPNB and caudal block provided similar postoperative analgesic effects without major complications for children under general anesthesia.