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Production of Violacein by a Novel Bacterium, Massilia sp. EP15224 Strain (Violacein을 생산하는 Massilia sp. EP15224 균주)

  • Yoon, Sang-Hong;Baek, Hee-Jin;Kwon, Soon-Wu;Lee, Chang-Muk;Sim, Joon-Soo;Hahn, Bum-Soo;Koo, Bon-Sung
    • Microbiology and Biotechnology Letters
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    • v.42 no.4
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    • pp.317-323
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    • 2014
  • Violacein has received much attention due to its various important biological activities, including broad-spectrum antibacterial and antifungal activity, anti-malarial, anti-tumoral, anti-oxidant, and anti-diarrheal activities. EP15224 strain isolated from forest soils in Korea was found to be a new species belonged to the genus Massilia based on its 16S ribosomal DNA sequences. The 16S ribosomal DNA of strain EP15224 displayed 97% homology with Massilia sp. BS-1, the nearest violacein-producing bacterium. Strain EP15224 produced bluish-purple pigment well in a synthetic MM2 medium containing glucose, $(NH_4)_2SO_4$, $Na_2HPO_4{\cdot}7H_2O$, $KH_2PO_4$, $MgSO_4{\cdot}7H_2O$, and 1 mM $\small{L}$-tryptophan. The chemical analysis of the pigment by LC/MS/MS showed that it is violacein with molecular weight of 343.34. This is the second report on the production of violacein by a Massilia species. In this study, the optimal culture conditions for violacein production were established under which 280 mg/l crude violacein was produced : glucose 2 g/l, $(NH_4)_2SO_4$ 1 g/l, $Na_2HPO_4{\cdot}7H_2O$ 2 g/l, $KH_2PO_4$ 1 g/l, $MgSO_4{\cdot}7H_2O$ 0.1 g/l, L-tryptophan 0.24 g/l, 25 ml medium in a 250 ml flask, with an inoculumn size of 10% (v/v), 72 h of cultivation with 250 rpm at $25^{\circ}C$.

The development of conductive 10B thin film for neutron monitoring (중성자 모니터링을 위한 전도성 10B 박막 개발)

  • Lim, Chang Hwy;Kim, Jongyul;Lee, Suhyun;Jung, Yongju;Choi, Young-Hyun;Baek, Cheol-Ha;Moon, Myung-Kook
    • Journal of Radiation Protection and Research
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    • v.39 no.4
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    • pp.199-205
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    • 2014
  • In the field of neutron detections, $^3He$ gas, the so-called "the gold standard," is the most widely used material for neutron detections because of its high efficiency in neutron capturing. However, from variable causes since early 2009, $^3He$ is being depleted, which has maintained an upward pressure on its cost. For this reason, the demands for $^3He$ replacements are rising sharply. Research into neutron converting materials, which has not been used well due to a neutron detection efficiency lower than the efficiency of $^3He$, although it can be chosen for use in a neutron detector, has been highlighted again. $^{10}B$, which is one of the $^3He$ replacements, such as $BF_3$, $^6Li$, $^{10}B$, $Gd_2O_2S$, is being researched by various detector development groups owing to a number of advantages such as easy gamma-ray discrimination, non-toxicity, low cost, etc. One of the possible techniques for the detection is an indirect neutron detection method measuring secondary radiation generated by interactions between neutrons and $^{10}B$. Because of the mean free path of alpha particle from interactions that are very short in a solid material, the thickness of $^{10}B$ should be thin. Therefore, to increase the neutron detection efficiency, it is important to make a $^{10}B$ thin film. In this study, we fabricated a $^{10}B$ thin film that is about 60 um in thickness for neutron detection using well-known technology for the manufacturing of a thin electrode for use in lithium ion batteries. In addition, by performing simple physical tests on the conductivity, dispersion, adhesion, and flexibility, we confirmed that the physical characteristics of the fabricated $^{10}B$ thin film are good. Using the fabricated $^{10}B$ thin film, we made a proportional counter for neutron monitoring and measured the neutron pulse height spectrum at a neutron facility at KAERI. Furthermore, we calculated using the Monte Carlo simulation the change of neutron detection efficiency according to the number of thin film layers. In conclusion, we suggest a fabrication method of a $^{10}B$ thin film using the technology used in making a thin electrode of lithium ion batteries and made the $^{10}B$ thin film for neutron detection using suggested method.

Isolation and Identification of Flavonoids from Corn Silk (옥수수수염에 함유된 Flavonoids의 분리 및 동정)

  • Kim, Sun-Lim;Kim, Mi-Jung;Lee, Yu-Young;Jung, Gun-Ho;Son, Beom-Young;Lee, Jin-Seok;Kwon, Young-Up;Park, Yong-Il
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.59 no.4
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    • pp.435-444
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    • 2014
  • This study was carried out to isolate and characterize the flavonoids present in corn silks. Maysin content in the unpollinated corn silks (Kwangpyeongok) showed its highest level at 3 days after silking, and decreased thereafter, while the content of open pollinated silks were consistently decreased after silking. This result indicates that the maysin content is considerably affected by the pollination of corn silk. Unpollinated corn silks were collected with excising, and ethanol employed to extract flavonoids at common temperature for 9 days. After extraction, chlorophyll, lipids etc. were removed with methylene chloride, then submitted to flash column cartridge ($150{\times}40mm$ i.d.) packed with a preparative $RP-C_{18}$ bulk packing material ($125{\AA}$, $55-105{\mu}m$), and monitored at 352 nm. Four fractions, fraction-I, -II, -III, and -IV, were isolated from ethanolic extract of corn silks. Absorption spectrum of fraction I showed its maximum intensity (${\lambda}_{max}$) at 327 nm and 239 nm, fraction-II showed its maximum intensity at 339 nm and 274 nm, fraction-III showed its maximum intensity at 345 nm and 277 nm, and fraction-IV showed its maximum intensity at 352 nm, 270 nm, 257 nm, respectively. On the baisis of ESI micro-TOF analysis, fraction-I was identified as chlorogenic acid (m/z 355, 3-(3,4-dihydroxycinnamoyl) quinic acid, $C_{16}H_{18}O_9$), fraction-II identified as a mixture of chlorogenic acid and luteolin 3'-methyl ether 7-glucuronosyl-($1{\rightarrow}2$)-glucuronide (m/z 653, $C_{28}H_{28}O_{18}$), fraction-III identified as a mixture of chlorogenic acid luteolin 7-O-neohesperidoside (m/z 595, $C_{27}H_{30}O_{15}$), and luteolin 3'-methyl ether 7-glucuronosyl-($1{\rightarrow}2$)-glucuronide, and fraction-IV identified as maysin (m/z 577, 2"-O-${\alpha}$-L-rhamnosyl-6-C-(6-deoxy-xylohexose-4-ulosyl)luteolin, $C_{27}H_{28}O_{14}$), respectively. From the ethanolic extract of corn silks, fraction-I was obtained about 35 mg/100 g F.W., fraction-II was about 48 mg/100 g F.W., fraction-III was about 46 mg/100 g F.W., and fraction-IV was about 138 mg/100 g F.W., respectively.

Development of an Official Analytical Method for Determination of Aclonifen in Agricultural Products Using GC-ECD (GC-ECD를 이용한 농산물 중 제초제 aclonifen의 공정분석법 확립)

  • Ko, Ah-Young;Kim, Hee-Jung;Jang, Jin;Lee, Eun-Hyang;Joo, Yoon-Ji;Kwon, Chan-Hyeok;Son, Young-Wook;Chang, Moon-Ik;Rhee, Gyu-Seek
    • Korean Journal of Environmental Agriculture
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    • v.33 no.4
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    • pp.388-394
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    • 2014
  • BACKGROUND: Aclonifen is used as a systemic and selective herbicide to control a wide spectrum broad-leaf weeds by inhibition carotenoid biosynthesis, and then its MRLs(Maximum Residue Limits) will be determined in onion and garlic. In this study, a new official method was developed for aclonifen determination in agricultural products to routinely inspect the violation of MRL as well as to evaluate the terminal residue level. METHODS AND RESULTS: Aclonifen was extracted from crop samples with acetone and the extract was partitioned with dichloromethane and then purified by silica solid phase extraction(SPE) cartridge. The purified samples were detected GC using an ECD detector. Limits of detection(LOD) was 0.001 mg/kg and quantification(LOQ) was 0.005 mg/kg, respectively. For validation purposes, recovery studies were carried out at three different concentration levels (LOQ, $10{\times}LOQ$, $50{\times}LOQ$, n=5). The recoveries were ranged from 74.3 to 95.0% with relative standard deviations(RSDs) of less than 8%. All values were consistent with the criteria ranges requested in the Codex guidelines(CAC/GL 40). CONCLUSION: The proposed analytical method was accurate, effective and sensitive for aclonifen determination and it will be used to as an official method in Korea.

Isolation, Quality Evaluation, and Seasonal Changes of Bakkenolide B in Petasites japonicus by HPLC (머위로부터 Bakkenolide B의 순수분리, HPLC분석 방법 및 채취 시기별 함량 분석)

  • Kim, Tae Hoon;Kim, Do Youn;Jung, Won Jung;Nagaiya, Ravichandran;Son, Beung Gu;Park, Young Hoon;Kang, Jum Soon;Lee, Young Jae;Im, Dong-Soon;Lee, Young-Geun;Choi, Yung Hyun;Choi, Young-Whan
    • Journal of Life Science
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    • v.24 no.3
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    • pp.252-259
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    • 2014
  • The leaves of Peatasites japonicus are a traditional oriental medicine with diverse biological activities. A simple and specific analytical method for the quantitative determination of bakkenolide B constituents from methanolic extract of the leaves of P. japonicus was developed. Bakkenolide B was isolated from the leaves of P. japonicus, and its structure was elucidated based on 1D, 2D NMR, and GC-MS spectral data. A liquid chromatographic method was developed to evaluate the quality of P. japonicus through determination of major active compound, bakkenolide B. The wavelengths at 254 and 215 nm were chosen to determine bakkenolide B. The recovery of the method was in the range of 98.6 to 103.1%, and bakkenolide B showed good linearity ($r^2$=0.999) within test ranges. The developed method was applied to the determination of bakkenolide B in the plant part and seasonal changes. The results showed that the content of bakkenolide B in the leaf was higher than in the petiole and rhizome. In this study, a simple, rapid, and reliable high-performance liquid chromatography method was used to determine the percentage and composition of bakkenolide B in P. japonicus procured from different Petasites species plants in South Korea. The method can be employed in routine quantitative analysis and quality control of different products in the market.

Quantum Chemical Calculations of the Effect of Si-O Bond Length on X-ray Raman Scattering Features for MgSiO3 Perovskite (양자화학계산을 이용한 Si-O 결합길이가 MgSiO3 페로브스카이트의 X-선 Raman 산란 스펙트럼에 미치는 영향에 대한 연구)

  • Yi, Yoo Soo;Lee, Sung Keun
    • Journal of the Mineralogical Society of Korea
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    • v.27 no.1
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    • pp.1-15
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    • 2014
  • Probing the electronic structures of crystalline Mg-silicates at high pressure is essential for understanding the various macroscopic properties of mantle materials in Earth's interior. Quantum chemical calculations based on the density functional theory are used to explore the atomic configuration and electronic structures of Earth materials at high pressure. Here, we calculate the partial density of states (PDOS) and O K-edge energy-loss near-edge structure (ELNES) spectra for $MgSiO_3$ perovskite at 25 GPa and 120 GPa using the WIEN2k program based on the full-potential linearized projected augmented wave (FP-LPAW) method. The calculated PDOS and O K-edge ELNES spectra for $MgSiO_3$ Pv show significant pressure-induced changes in their characteristic spectral features and relative peak intensity. These changes in spectral features of $MgSiO_3$ Pv indicate that the pressure-induced changes in local atomic configuration around O atoms such as Si-O, O-O, and Mg-O length can induce the significant changes on the local electronic structures around O atoms. The result also indicates that the significant changes in O K-edge features can results from the topological densification at constant Si coordination number. This study can provide a unique opportunity to understand the atomistic origins of pressure-induced changes in local electronic structures of crystalline and amorphous $MgSiO_3$ at high pressure more systematically.

A Study on the Imitation and Transformation of Gugok-Wonlim Culture through Management of the Myungam Jeong Sik's Muyi-Gugok in Sancheong (명암(明庵) 정식(鄭拭)의 산청 무이구곡(武夷九曲) 원림경영을 통해 본 구곡문화의 모방과 변용)

  • Rho, Jae-Hyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.33 no.3
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    • pp.84-94
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    • 2015
  • This study is to examine how the admiration for Chutzu(朱子)'s achievement while he was preaching his policies after renouncing the world in Wuyi-Gugok(武夷九曲), Mt. Wuyi and Joseon-style transformation culture were unfolded and developed through Gugok management cases such as position, name, poetic diction, Jungsa(精舍) architecture and engraving of Muyi-Gugok set in Mt. Gugok, Snacheong. The results were as follows: Myungam(明庵) Jeong Sik(鄭拭, 1683~1746)'s Muyi-Gugok, which consists of Suhongkyo(垂虹橋, gok 1) - Oknyeobong(玉女峰) - Nhongwhaldam(弄月潭) - Nacwhadam(落花潭) - Daeeunbyeong(大隱屛) - Gwangpyungryea(光風瀨) - Jaewhaldae(霽月臺) - Gorooam(鼓樓巖) - Wharyongpok(臥龍瀑, gok 9) is the representative case where Chutzu's Wuyi-Gugok was exactly copied and fulfilled to the Joseon Dynasty. In a large frame, Gugok Wonlim culture, Myungam's Muyi-Gugok management has a will of succession of Dotong(道統) through admiration for Chutzu in a rigid way. Another name of Mt. Gugok is Mt. Muyi and Gugok's name is Muyi-Gugok and the residence existed between gok 4 and gok 5. In addition, the name of Jeongsa for Gugok management is also 'Muyi Jeongsa(武夷精舍)' and Gugok name and contents of Poetry are also similar and all of these are clear evidence that Myungam tries to copy Chutzu's Wuyi-Gugok to Mt. Gugok. Also, Gugok set before Myungam were located in Mt. Gugok and among them, verified four Gugok names are corresponded to those of Chutzu's Wuyi-Gugok and it tells that conforming behavior as one of admiration ways for Chutzu already arrived at Mt. Gugok before Myungam and this was an oppotunty to widen Mt. Gugok Muyi-Gugok's tradition and horizon. Also, considering that Myungam's gok 6, Gwangpyungryea and gok 7, Jewoldae are names from 'Gwangpungjewol(光風霽月)' Based on Chutzu's poem and they are closely related to Joseon's classical scholar spirit, they are associated with Joseon-style transformation of Chutzu's Muyi-Gugok. Meanwhile, gok 5 'Daeeunbyeong' was transformed to 'Nangaam(爛柯巖)' in gok 5 - "Deoksan-Gugok(德山九曲) of Jooko(竹塢) Ha Beom-Woon(河範運, 1792~1858) and those characters's engravings are handed down. In "Pome of Deoksan Gugok" transformed from Myungam's Muyi-Gugok, respect and admiration for Chutzu is weaken while Ha Beom-Woon admires Nammyeong(南冥) Cho shik(曺植, 1501~1572), a symbolic character of himself's school and from this, a movement to promote partisan unity is identified. After Myungam died, Muyi-Gugok in Mt. Gugok was transformed from a space to succeed Chutzu's Dotonga to one to commemorate the memory of ancient sages, but, it is a typicality case that widen the spectrum of Joseon's Gugok-Wonlim culture through Muyi-Gugok's imitation and transformation.

Characteristics of Flora on Dry Field Margins in Korean Peninsula (밭경작지 주변부의 식물 종조성 및 특성)

  • Kim, Myung-Hyun;Choi, Soon-Kun;Kim, Min-Kyeong;Choe, Lak-Jung;Hong, Seong-Chang;Jung, Goo-Bok;Cho, Kwang-Jin;Han, Donguk;Oh, Young-Ju;Lee, Wook-Jae;Yang, Dongwoo;Park, Sangkyu;Na, Young-Eun
    • Korean Journal of Environmental Agriculture
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    • v.34 no.2
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    • pp.77-90
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    • 2015
  • BACKGROUND: The field margins, which are uncultivated area of permanent vegetation located adjacent to field, play an important role in enhancing biodiversity in the agricultural ecosystem. This study focused on floristic characteristics on dry field margins in Korea Peninsula. METHODS AND RESULTS: This study was conducted at margins of 196 dry fields in 32 areas in 8 provinces in May and September 2013. The vascular plants of the dry field margins were listed 347 taxa which contain 73 families, 219 genera, 311 species, 1 subspecies, 30 varieties and 5 forms. Of these 347 taxa, 48 taxa were woody plants and 299 taxa were herbaceous plants. Among total 73 families, Compositae (17.6%) was the most dominant family, and followed Gramineae (15.9%), Polygonaceae (5.8%), Leguminosae (4.9%) and Cyperaceae (3.8%). Based on relative frequency values of survey fields, the appearance frequency of Digitaria ciliaris (89.8%) was the highest, and followed Acalypha australis (86.2%), Artemisia princeps (82.1%), Commelina communis (80.6%) and Portulaca oleracea (80.6%). Disturbance index of dry field margins was 55.0% at national level, and Gangwon region was the highest among the 8 regions at regional level. Life form spectrum was determined to be $Th-R_5-D_4-etype$. CONCLUSION: These results will be used fundamental data for studies to improve or even stabilize the current state of plant biodiversity in agricultural environments.

Stenotrophomonas maltophilia and Ventilator-Associated Pneumonia in Critically Ill Pediatric Patients: a Retrospective Analysis at a Single Center (소아 환자에서 Stenotrophomonas maltophilia와 인공 환기요법 관련 폐렴에 관한 연구)

  • Lee, Byung-Kee;Choi, Soo-Han;Kim, Soo Jin;Cho, Joong Bum;Ae, Hong;Yoo, So-young;Kim, Ji Hye;Lee, Nam Young;Kim, Yae-Jean
    • Pediatric Infection and Vaccine
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    • v.22 no.2
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    • pp.75-80
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    • 2015
  • Purpose: Ventilator-associated pneumonia (VAP) is a serious threat in critically ill pediatric patients. Data regarding Stenotrophomonas maltophilia VAP in pediatric population is limited. We evaluated the clinical data of S. maltophilia associated VAP in critically ill pediatric patients. Methods: A retrospective chart review was performed in pediatric patients 18 years old or younger who developed S. maltophilia associated VAP at Samsung Medical Center, Seoul Korea from January 2008 to December 2012. Results: A total of 31 patients were identified S. maltophilia associated VAP. Median age was 8 months (range, 0.5 month to 16.6 years) and 13 patients were male (40.6%). Underlying illnesses were cardiologic diseases (n=11, 34.4%), hematologic oncologic malignancies (n=7, 25%), neurologic diseases (n=4, 12.5%), pulmonary diseases (n=3, 9.4%), and others (n=4, 12.5%). The median duration of ventilator use before S. maltophilia VAP diagnosis was 14 days (range, 4-256 days). Overall mortality at 30 days was 12.5% (4/32). Conclusions: S. maltophilia should be also considered as a possible pathogen for VAP in critically ill pediatric patients. Empiric antibiotic choice should include agents that are active against S. maltophilia in patients who are deteriorating on broad spectrum beta-lactam antimicrobial agents.

Minimal Invasive Surgery: A National Survey of Its Members by the Korean Association of Pediatric Surgeons (최소 침습 수술: 대한소아외과학회 회원을 대상으로 한 전국조사)

  • Kim, Dae Yeon;Kim, I.S.;Kim, H.Y.;Nam, S.H.;Park, K.W.;Park, W.H.;Park, Y.J.;Park, J.H.;Park, J.Y.;Park, J.S.;Park, J.Y.;Boo, Y.J.;Seo, J.M.;Seol, J.Y.;Oh, J.T.;Lee, N.H.;Lee, M.D.;Jang, J.H.;Jung, K.H.;Jung, S.Y.;Jung, S.E.;Jung, S.M.;Jung, E.Y.;Jung, J.H.;Cho, M.J.;Choi, K.J.;Choi, S.J.N.;Choi, S.O.;Choi, S.H.;Choi, Y.M.;Hong, J.
    • Advances in pediatric surgery
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    • v.20 no.1
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    • pp.1-6
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    • 2014
  • Minimal invasive surgery (MIS) has rapidly gained acceptance for the management of a wide variety of pediatric diseases. A questionnaire was sent to all members of the Korean Association of Pediatric Surgeons. Thirty one members (25.4%) took part in the survey that included data for the year 2012: demographic details, opinion regarding minimal invasive surgery and robotic surgery, spectrum of minimally invasive operations, and quantity of procedures. 48.4% of the respondents had more than 10 years experience, 35.5% less than 10 years experience, and 16.1 % had no experience. The respondents of the recommend MIS and perform MIS for surgical procedures are as follow; inguinal hernia (61.3%), simple appendicitis (87.1%), complicated appendicitis (80.6%), reduction of intussusceptions (83.9%), pyloromyotomy (90.3%), fundoplication (96.8%), biopsy and corrective surgery of Hirschsprung's disease (93.5%/90.3%), imperforate anus (77.4%), congenital diaphragmatic hernia (80.6%), and esophageal atresia (74.2%). The MIS procedures with more than 70% were lung resection (100%), cholecystectomy (100%), appendectomy (96.2%), ovarian torsion (86.7%), fundoplication (86.8%), hiatal hernia repair (82.6%), and splenectomy (71.4%). The MIS procedures with less than 30% were congenial diaphragmatic hernia reapir (29.6%), esophageal atresia (26.2%), correction of malroatation (24.4%), inguinal hernia repair (11.4%), anorectal malformation (6.8%), Kasai operation (3.6%).