• Title/Summary/Keyword: L.D.V

Search Result 1,212, Processing Time 0.035 seconds

TRAO Multi-beam Legacy Survey of Nearby Filamentary Molecular Clouds : Progress Report

  • Kim, ShinYoung;Chung, Eun Jung;Lee, Chang Won;Myers, Philip C.;Caselli, Paola;Tafalla, Mario;Kim, Gwanjeong;Kim, Miryang;Soam, Archana;Gophinathan, Maheswar;Liu, Tie;Kim, Kyounghee;Kwon, Woojin;Kim, Jongsoo
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.42 no.1
    • /
    • pp.32.1-32.1
    • /
    • 2017
  • To dynamically and chemically understand how filaments, dense cores, and stars form under different environments, we are conducting a systematic mapping survey of nearby molecular clouds using the TRAO 14 m telescope with high ($N_2H^+$ 1-0, $HCO^+$ 1-0, SO 32-21, and $NH_2D$ v=1-0) and low ($^{13}CO$ 1-0, $C^{18}O$ 1-0) density tracers. The goals of this survey are to obtain the velocity distribution of low dense filaments and their dense cores for the study of their origin of the formation, to understand whether the dense cores form from any radial accretion or inward motions toward dense cores from their surrounding filaments, and to study the chemical differentiation of the filaments and the dense cores. Until Feb. 2017, the real OTF observation time is 460 hours. We have almost completed mapping observation with four molecular lines ($^{13}CO$ 1-0, $C^{18}O$ 1-0, $N_2H^+$ 1-0, and $HCO^+$ 1-0) on the five regions of molecular clouds (L1251 of Cepheus, Perseus west, Polaris south, BISTRO region of Serpense, California, and Orion B). The maps of a total area of $7.38deg^2$ for both $^{13}CO$ and $C^{18}O$ lines and $2.19deg^2$ for both $N_2H^+$ and $HCO^+$ lines were obtained. All OTF data were regridded to a cell size of 22 by 22 arcseconds. The $^{13}CO$ and $C^{18}O$ data show the RMS noise level of about 0.22 K and $N_2H^+$ and $HCO^+$ data show about 0.14 K at the velocity resolution of 0.06 km/s. Additional observations will be made on some regions that have not reached the noise level for analysis. We are refining the process for a massive amount of data and the data reduction and analysis are underway. This presentation introduces the overall progress from observations to data processing and the initial analysis results to date.

  • PDF

A comprehensive review of microplastics: Sources, pathways, and implications (미세 플라스틱의 종합적 고찰: 근원, 경로 및 시사점)

  • Yano, K.A.V.;Reyes, N.J.D.G.;Geronimo, F.K.F.;Jeon, M.S.;Kim, Y.;Kim, L.H.
    • Journal of Wetlands Research
    • /
    • v.22 no.2
    • /
    • pp.153-160
    • /
    • 2020
  • Most studies defined microplastic (MP) as plastic particles less than 5 mm. The ubiquity of MP is raising awareness due to its potential risk to humans and the environment. MP can cause harmful effects to humans and living organisms. This paper review aimed to provide a better understanding of the sources, pathways, and impacts of MP in the environment. MP can be classified as primary and secondary in nature. Moreover, microplastic can also be classified as based on its physical and chemical characteristics. Stormwater and wastewater are important pathways of introducing MP in large water bodies. As compared to stormwater, the concentrations of MP in wastewater were relatively lower since wastewater treatment processes can contribute to the removal of MP. In terms of polymer distribution, wastewater contains a wider array of polymer varieties than stormwater runoff. The most common types of polymer found in wastewater and stormwater runoff were polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), polyethylene (PE) and polyethylene terephthalate (PET). The continuous discharge and the increasing number of MP in the environment can pose greater hazards and harmful effects on humans and other living organisms. Despite the growing number of publications in relation to MP, further studies are needed to define concrete regulations and management strategies for mitigating the detrimental effects of MP in the environment.

Phenotypic and Molecular Characteristics of Children with Progressive Familial Intrahepatic Cholestasis in South China

  • Zhang, Wen;Lin, Ruizhu;Lu, Zhikun;Sheng, Huiying;Xu, Yi;Li, Xiuzhen;Cheng, Jing;Cai, Yanna;Mao, Xiaojian;Liu, Li
    • Pediatric Gastroenterology, Hepatology & Nutrition
    • /
    • v.23 no.6
    • /
    • pp.558-566
    • /
    • 2020
  • Purpose: Progressive familial intrahepatic cholestasis (PFIC) is a rare genetic autosomal recessive disease caused by mutations in ATP8B1, ABCB11 or ABCB4. Mutational analysis of these genes is a reliable approach to identify the disorder. Methods: We collected and analyzed relevant data related to clinical diagnosis, biological investigation, and molecular determination in nine children carrying these gene mutations, who were from unrelated families in South China. Results: Of the nine patients (five males, four females) with PFIC, one case of PFIC1, four cases of PFIC2, and four cases of PFIC3 were diagnosed. Except in patient no. 8, jaundice and severe pruritus were the major clinical signs in all forms. γ-glutamyl transpeptidase was low in patients with PFIC1/PFIC2, and remained mildly elevated in patients with PFIC3. We identified 15 different mutations, including nine novel mutations (p.R470HfsX8, p.Q794X and p.I1170T of ABCB11 gene mutations, p.G319R, p.A1047P, p.G1074R, p.T830NfsX11, p.A1047PfsX8 and p.N1048TfsX of ABCB4 gene mutations) and six known mutations (p.G446R and p.F529del of ATP8B1 gene mutations, p.A588V, p.G1004D and p.R1057X of ABCB11 gene mutations, p.P479L of ABCB4 gene mutations). The results showed that compared with other regions, these three types of PFIC genes had different mutational spectrum in China. Conclusion: The study expands the genotypic spectrum of PFIC. We identified nine novel mutations of PFIC and our findings could help in the diagnosis and treatment of this disease.

Allelopathic Effect of Sorghum Extract and Residues on Selected Crops and Weeds (수수의 타감작용(他感作用)에 관(關)한 연구(硏究))

  • Kim, S.Y.;De Datta, S.K.;Robles, R.P.;Kim, K.U.;Lee, S.C.;Shin, D.H.
    • Korean Journal of Weed Science
    • /
    • v.14 no.1
    • /
    • pp.34-41
    • /
    • 1994
  • To better understand the allelopathic effect of sorghum(Sorghum vulgare L.), the inhibitory activities of water extracts of the stem, leaf and root, and of residues of the stem to major crops and weeds associated with them were evaluated. The allelopathic activity of sorghum plants was species specific, and depended on source and concentration. Germination, and shoot and root length of all test species were inhibited by the different concentrations of the stem extract. Among the crop species, radish showed the most inhibition, followed by wheat and rice. Maize was the least sensitive species. Of the weed species, Ipomoea triloba was most inhibited, followed by Echinochloa colona and Rottboellia cochinchinensis. The water extracts of leaves, stems, and roots significantly inhibited germination and seedling growth in E. colona and radish. The stem extract gave the greatest inhibitory effect on E. colona while all three extracts produced similar response in radish. In the greenhouse trial, sorghum stem residue placed on the soil surface as mulch significantly inhibited seedling growth in E. colona and radish, but not that in rice.

  • PDF

The Crystal Structure of Bis(1,2-diaminopropane)palladium(Ⅱ) Bis(oxalato)palladate(Ⅱ) (Bis(1,2-diaminopropane)palladium(Ⅱ) Bis(oxalato)palladate(Ⅱ)의 결정구조)

  • Kim Sei Hwan;NagGung Hae;Jeon, Ho Jung
    • Journal of the Korean Chemical Society
    • /
    • v.37 no.6
    • /
    • pp.599-603
    • /
    • 1993
  • Crystal structure of bis(1,2-diaminopropane)palladium(II) bis(oxalato)palladate(II) has been determined by X-ray crystallography. Crystal data: $Pd_2C_{10}H_{10}N_{4}O_{8}$, $M_W$ = 573.09, orthorhombic, space group $P_{ccn}$ (No = 56), a = 16.178(5), b = 16.381(6), c = 6.685(2)$\{AA}$, V = 1771.6 $\{AA}^3$, $M_W$W = 573.09, $D_c$ = 2.014 g${\cdot}c\;m^{-3}$, Z = 4, T = 294K, F(000) = 1056.0 and $\mu$ = 20.466 c$m^{-1}$. The intensity data were collected with $Mo-K\alpha$ radiation (${\lambda}$ = 0.7107 $\AA)$ on an automatic four-circle diffractometer with a graphite monochromater. The structure was solved by Patterson method and refined by full matrix least-squares methods using Pivot weights. The final R and S values were R = 0.065, $R_W = 0.059, R_{all}$ = 0.065 and S = 4.315 for 605 observed reflections. Both cation and anion complexes are essentially planar and have dihedral angle of $18(l)^{\circ}$ between thier planes. In the crystal structure, they do not have the Magnus's salt type mixed stacks; instead, the complex anions form regular stacks along the c-axis with the M-M bond length of $3.343(5)\AA$ and their stacks are surrounded by the complex cations through hydrogen bonds with the nitrogen-oxygen distances of 2.94(3) and $3.31(4)\AA.$

  • PDF

Luminescence Characteristic of CNT Element in ZnS:(Cu, Al) Thin Film Fabricated by a Screen Printing Method (스크린 프린팅 방법으로 제작한 ZnS:(Cu, AL) 박막의 CNT 불순물 첨가에 의한 광학적 특성에 관한 연구)

  • Shon, Pong-Kyun;Shin, Jun-Ha;Bea, Jae-Min;Lee, Jae-Bum;Kim, Jong-Su;Lee, Sang-Nam
    • Journal of the Korean Graphic Arts Communication Society
    • /
    • v.29 no.1
    • /
    • pp.23-33
    • /
    • 2011
  • This experimental focus to characterize luminescence properties related to CNT (Carbon Nano Tube) element dispersedly implanted in ZnS-based phosphor thin film panel fabricated by a screen printing method. More specifically FE-SEM measurements, L-V(Luminescence vs. Voltage) and photo luminescence were carried out to determine an optimum value of CNT concentration and film thickness for the thin film structure of CNT-ZnS:(Cu, Al) by the screen printing method. We confirmed that an optimum value of CNT concentration in the ZnS:(Cu, Al) film panel is about 0.75 wt% resulting that the electric conductivity is 1.6 times higher than that of pure CNT sample and showing that the luminescence intensity is increasing until the optimum concentration. Clearly, CNT is presenting in the luminescence process providing a pathway for the creation of hot electron and a channel for the electron-hole recombination but overly inserted CNT may hinder to produce the hot electron for making an avalanching process. In case of the overly doped CNT 1.0 wt% in the ZnS-based phosphor, the luminescence intensity is decreasing although the electric conductivity is exponentially increasing. Based on these results, we realized that hot electron occurred by the external electric field or exciton arose by the external photon source are reduced dramatically over the critical value of CNT concentration because CNT element provide various isolated residues in the composites of ZnS based phosphor rather than pathway or channel for the D-A(Donnor to Acceptor) pair transition or the radiative recombination of electron-hole.

Die Ansichtsverschiedenheit zwischen Abendland und Morgenland über Spielbegriff ('놀이' 개념에 대한 동, 서양의 시각차에 관하여 - '몰입' 놀이와 '거리두기' 놀이 -)

  • Choi, Go-won
    • Journal of Korean Philosophical Society
    • /
    • v.117
    • /
    • pp.373-397
    • /
    • 2011
  • Nicht nur in Philosophie sondern auch im Bereich der meinsten Geisteswissenschaften $best{\ddot{a}}rkt$ sich die Gewichtigkeit des Spielbegriffs immer mehr. Aus diesem Grund wird 'Spiel' in den $vielf{\ddot{a}}ltigen$ Wissenschaftsbereichen, in $vielf{\ddot{a}}ltiger$ Weise definiert, und diese Definitionen sind im Gebrauch auch in $vielf{\ddot{a}}ltiger$ Weise. Aber trotz dieser mit Spiel $zusammenh{\ddot{a}}ngenden$ '$Vielf{\ddot{a}}ltigkeiten$' liegt immer eine identische Voraussetzung am Boden der Definitionen oder Theorien des Spiels, und das ist nichts anderes als, dass Spiel ausnahmslos eine Vertieftsein-$T{\ddot{a}}tigkeit$ ist. Anders gesagt, dass es kein Spiel gibt, in dem man sich nicht $v{\ddot{o}}llig$ aufgeht. Aber diese Ansicht ist vorwiegend nur im Abendland in Geltung, und deswegen ist es sehr bedenklich, ob man das auch auf dem Morgenland gleichfalls zutreffen $k{\ddot{o}}nnte$. Grund $daf{\ddot{u}}r$ ist, dass, weil das traditionelle $Lebensgef{\ddot{u}}hl$ nicht in einem Tage gebildet worden ist, $l{\ddot{a}}sst$ sich es nicht vermeiden, dass dieses $Lebensgef{\ddot{u}}hl$ auf alles, was mit dem Leben Zusammenhang steht, einen unmittelbaren Einfluss $aus{\ddot{u}}bt$. Dann kann man sagen, dass das sich $nat{\ddot{u}}rlich$ in der Ansicht zum Spiel widerspiegelt. Aus diesem Urteil wird man in dieser Arbeit den Vertieftseinsbegriff und den Verfremdungsbegriff gegeneinander stellen, und folglich, wenn man die 'Verfremdung' $f{\ddot{u}}r$ einen sonstigen Charakter des Spiels erachten kann, muss man sie auch in Rechnung ziehen, falls man Spielbegriff studieren will.

Analysis of Antimicrobial Substance isolated from Scutellariae Radix Extract using LC-MS (LC-MS를 이용한 황금추출물의 항균물질 검색)

  • Kim Young-Rok;Choi Sung-Gil;Cho Sung-Hwan
    • Food Science and Preservation
    • /
    • v.12 no.4
    • /
    • pp.350-354
    • /
    • 2005
  • It was carried out for development of natural antimicrobial on Scutellariae Radix by measuring the general nutritional composition and mineral contents. This study analyzed it with LC-MS to identify antimicrobial activity substance in the Scutellariae Radix extract, its content was analyzed using HPLC. The searching substance was examined antimicrobial activity by disk method. The approximate composition of Scutellariae Radix was $8.93\%$ of moisture, $4.13\%$ of crude ash, $15.30\%$ of crude protein, $3.71\%$ of crude fat, $67.93\%$ of carbohydrate, respectively. Scutellariae Radix was contained high contents of minerals such as K(12,050 mg/kg),. Mg(4,295 mg/kg), remarkably. It was identified that molecular weight 445' peak was baicalin, molecular weight 283' peak was wogonin and molecular weight 269' peak was baicalein on Scutellariae Radix extract Baicalin showed remarkable antimicrobial activity against V. parahaemolyticus and L monocytogenes when examined by disk method, which was estimated antimicrobial activity substance in the Scutellariae Radix extract. The content of baicalin was $0.75\%$(with D.W.) and $0.82\%$(with methanol) in the Scutellariae Radix extract using HPLC.

Comparative assessment of urban stormwater low impact strategies equipped with pre-treatment zones (침강지 시설이 조성된 LID 시설의 환경적 영향평가)

  • Yano, K.A.V.;Reyes, N.J.D.G.;Jeon, M.S.;Kim, L.H.
    • Journal of Wetlands Research
    • /
    • v.21 no.2
    • /
    • pp.181-190
    • /
    • 2019
  • Recently, Low impact development techniques, a form of nature-based solutions (NBS), were seen cost-efficient alternatives that can be utilized as alternatives for conventional stormwater management practices. This study evaluated the effectiveness of an infiltration trench (IT) and a small constructed wetland (SCW) in treating urban stormwater runoff. Long-term monitoring data were observed to assess the seasonal performance and cite the advantages and disadvantages of utilizing the facilities. Analyses revealed that the IT has reduced performance during the summer season due to higher runoff volumes that exceeded the facility's storage volume capacity and caused the facility to overflow. On the other hand, the pollutant removal efficiency of the SCW was impacted by the winter season as a result of dormant biological activities. Sediment data also indicated that fine and medium sand particles mostly constituted the trapped sediments in the pretreatment and media zones. Sediments in SCW exhibited a lower COD and TN load due to the phytoremediation and microbiological degradation capabilities of the system. This study presented brief comparison LID facilities equipped with pre-treatment zones. The identified factors that can potentially affect the performance of the systems were also beneficial in establishing metrics on the utilization of similar types of nature-based stormwater management practices.

A STUDY ON IN VIVO AND IN VITRO AMALGAM CORROSION (아말감의 구강내 부식 및 인공 부식에 관한 연구)

  • Lim, Byong-Mok;Kwon, Hyuk-Choon;Um, Chung-Moon
    • Restorative Dentistry and Endodontics
    • /
    • v.22 no.1
    • /
    • pp.1-33
    • /
    • 1997
  • The objective of this study was to analyze the in vitro and in vivo corrosion products of low and high copper amalgams. The four different types of amalgam alloy used in this study were Fine cut, Caulk spherical, Dispersalloy, and Tytin. After each amalgam alloy and Hg were triturated according to the directions of the manufacturer by means of the mechanical amalgamator(Amalgam mixer. Shinhung Co. Korea), the triturated mass was inserted into a cylindrical metal mold which was 12mm in diameter and 10mm in height. The mass was condensed by 150Kg/cm compressive force. The specimen was removed from the mold and aged at room temperature for about seven days. The standard surface preparation was routinely carried out by emery paper polishing under running water. In vitro amalgam specimens were potentiostatically polarized ten times in a normal saline solution at $37^{\circ}C$(potentiostat : HA-301. Hukuto Denko Corp. Japan). Each specimen was subjected to anodic polarization scan within the potential range -1700mV to+400mV(SCE). After corrosion tests, anodic polarization curves and corrosion potentials were obtained. The amount of component elements dissolved from amalgams into solution was measured three times by ICP AES(Inductive Coupled Plasma Atomic Emission Spectrometry: Plasma 40. Perkim Elmer Co. U.S.A.). The four different types of amalgam were filled in occlusal and buccal class I cavities of four human 3rd molars. After about five years the restorations were carefully removed after tooth extraction to preserve the structural details including the deteriorated margins. The occlusal surface, amalgam-tooth interface and the fractured surface of in vivo amalgam corrosion products were analyzed. In vivo and in vitro amalgam specimens were examined and analyzed metallographically by SEM(Scanning Electron Microscope: JSM 840. Jeol Co. Japan) and EDAX(Energy Dispersive Micro X-ray Analyser: JSM 840. Jeol Co. Japan). 1. The following results are obtained from in vitro corrosion tests. 1) Corrosion potentials of all amalgams became more noble after ten times passing through the in vitro corrosion test compared to first time. 2) After times through the test, released Cu concentration in saline solution was almost equal but highest in Fine cut. Ag and Hg ion concentration was highest in Caulk spherical and Sn was highest in Dispersalloy. 3) Analyses of surface corrosion products in vitro reveal the following results. a)The corroded surface of Caulk spherical has Na-Sn-Cl containing clusters of $5{\mu}m$ needle-like crystals and oval shapes of Sn-Cl phase, polyhedral Sn oxide phase. b)In Fine cut, there appeared to be a large Sn containing phase, surrounded by many Cu-Sn phases of $1{\mu}m$ granular shapes. c)Dispersalloy was covered by a thick reticular layer which contained Zn-Cl phase. d)In Tytin, a very thin, corroded layer had formed with irregularly growing Sn-Cl phases that looked like a stack of plates. 2. The following results are obtained by an analysis of in vivo amalgam corrosion products. 1) Occlusal surfaces of all amalgams were covered by thick amorphous layers containing Ca-P elements which were abraded by occlusal force. 2) In tooth-amalgam interface, Ca-P containing products were examined in all amalgams but were most clearly seen in low copper amalgams. 3) Sn oxide appeared as a polyhedral shape in internal space in Caulk spherical and Fine cut. 4) Apical pyramidal shaped Sn oxide and curved plate-like Sn-Cl phases resulted in Dispersalloy. 5) In Tytin, Sn oxide and Sn hydroxide were not seen but polyhedral Ag-Hg phase crystal appeared in internal space which assumed a ${\beta}_l$ phase.

  • PDF