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The Crystal Structure of Cinmetacin ($C_{21}H_{19}NO_4$), A Non-steroidal Antiinflammatory Agent

  • Kim, Yang-Bae;Park, Il-Yeong;Park, Yang-Hwan
    • Archives of Pharmacal Research
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    • v.12 no.1
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    • pp.52-57
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    • 1989
  • The structure of cinmetacin was determined by single crystal X-ray diffraction analysis. The compound was recrystallized from a mixture of acetone and water in orthorhombic, space group $P2_12_12_1$, with Z=4, a=35.681(8), b=9.482(2), c:5.071(1) ${\AA}$, $D_x=1.352 g/cm^3$, and $D_m=1.35g/cm^3$. The structure was solved by direct method and refined by least-squares procedure to the final R value of 0.036 for 1441 observed reflections ($F{\geq}3{\sigma}(F)$). The carboxyl group of the molecule is nearly perpendicular to the indole ring. The dihedral angle between indole ring and phenyl group is $64.5^{\circ}$. The molecules are linked together via O(1)-H ----O(3) hydrogen bonds, and arranged along 2-fold screw axis in the crystal. The intermolecular contacts are the normal van der Waals' forces.

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The Crystal Structure of Fenbufen, 3-(4-biphenylylcarbonyl)propionic acid ($C_{16}H_{14}O_3$), A Non-steroidal Antiinflammatory Agent

  • Kim, Yang-Bae;Park, Il-Yeong;Park, Yang-Hwan
    • Archives of Pharmacal Research
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    • v.11 no.2
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    • pp.127-133
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    • 1988
  • The crystal structure of fenbufen was determined by X-ray diffraction techniuques. The compound was recrystallized in orthorhombic crystal system, space group $Pca2_1$ a = 31. 918(10), b = 5.550 (2), c = 15.078 (9) ${\AA}, D_m$= $1.26, {\D_x$= 1.264 g/$\textrm{cm}^3$, and Z = 8. The structure was solved by direct methods and refined by least squares procedure to the final R value of 0.051 for 1780 independent reflections. Two molecules in the asymmetric unit are related by a pseudo center of symmetry and dimerized via O-H...O hydrogen bonds. The carbonyl group attached to the phenyl ring is nearly coplanar to the ring. In the crystal the molecules are arranged in paralle stacks in the a direction.

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BIPACKING A BIPARTITE GRAPH WITH GIRTH AT LEAST 12

  • Wang, Hong
    • Journal of the Korean Mathematical Society
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    • v.56 no.1
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    • pp.25-37
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    • 2019
  • Let G be a bipartite graph with (X, Y ) as its bipartition. Let B be a complete bipartite graph with a bipartition ($V_1$, $V_2$) such that $X{\subseteq}V_1$ and $Y{\subseteq}V_2$. A bi-packing of G in B is an injection ${\sigma}:V(G){\rightarrow}V(B)$ such that ${\sigma}(X){\subseteq}V_1$, ${\sigma}(Y){\subseteq}V_2$ and $E(G){\cap}E({\sigma}(G))={\emptyset}$. In this paper, we show that if G is a bipartite graph of order n with girth at least 12, then there is a complete bipartite graph B of order n + 1 such that there is a bi-packing of G in B. We conjecture that the same conclusion holds if the girth of G is at least 8.

Synthesis and Properties of Dicyclohexyltin(IV) Complexes. Structure of $Cy_2Sn(S_2CNMe_2)_2 $

  • Jung, Ok-Sang;Kim, Min-Jung;Jeong, Jong-Hwa;Sohn, Youn-Soo
    • Bulletin of the Korean Chemical Society
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    • v.10 no.4
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    • pp.343-346
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    • 1989
  • Dicyclohexyltin(IV) complexes $Cy_2SnX (X = O,\;S,\;(Me_2NCS_2)_2)$ have been prepared and characterized by means of elemental analysis, cryoscopic data, and IR spectroscopy. X-ray structure determination for $Cy_2Sn(S_2CNMe_2)_2$ (monoclinic; P2/c;a = 8.992(1), b = 6.688(1), c = 19.453(2) ${\AA},\;{\beta}$ = 96.556(7) ; R = 0.041) has shown that the molecule is $C_2$-symmetric with both dithiocarbamate ligands bonding in anisobidentate mode and the local geometry around the hexacoordinate Sn(IV) atom is a distorted octahedral arrangement with the two cyclohexyl groups in trans position. The physical and chemical properties measured suggest polymeric and trimeric structures for $Cy_2SnO\;and\;Cy_2SnS$, respectively.

High-pressure synchrotron X-ray diffraction study of tremolite and actinolite in various fluids

  • Kong, Mihye;Vogt, Thomas;Lee, Yongjae
    • Current Applied Physics
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    • v.18 no.11
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    • pp.1218-1224
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    • 2018
  • Pressure-dependent structural and morphological changes of two amphibole minerals, tremolite and actinolite, were investigated up to 7.0 GPa using synchrotron X-ray powder diffraction underthree different pressure transmission media (PTM): water (W), $CO_2$ and silicone oil (SI). The elastic response of tremolite and actinolite are found to be dependent on the PTM used. When using water (W) as PTM, tremolite and actinolite show normal volume contractions with bulk moduli of 74(1) and 78(1) GPa, respectively. When using $CO_2$ as PTM, we observe the formation of calcite from tremolite above 3.8(1) GPa, whereas actinolite did not show any carbonation reaction. Under silicone oil PTM, we observe modulated volume contraction behaviors in both samples, compared to water and $CO_2$ PTM, with bulk moduli in the order of 90(1) and 94(4) GPa for tremolite and actinolite, respectively.

Pneumonia Detection from Chest X-ray Images Based on Sequential Model

  • Alshehri, Asma;Alharbi, Bayan;Alharbi, Amirah
    • International Journal of Computer Science & Network Security
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    • v.22 no.4
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    • pp.53-58
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    • 2022
  • Pneumonia is a form of acute respiratory infection that affects the lungs. According to the World Health Organization, pneumonia is the leading cause of death for children worldwide. As a result, pneumonia was the top killer of children under the age of five years old in 2015, which is 15% of all deaths worldwide. In this paper, we used CNN model architectures to compare between the result of proposed a CNN method with VGG based model architecture. The model's performance in detecting pneumonia shows that the proposed model based on VGG can classify normal and abnormal X-rays effectively and more accurately than the proposed model used in this paper.

Synthesis and Electrochemical Performance of Microporous Hollow Carbon from Milkweed Pappus as Cathode Material of Lithium-Sulfur Batteries

  • Jun-Ki Kim;Yunju Choi;Euh Duck Jeong;Sei-Jin Lee;Hyun Gyu Kim;Jae Min Chung;Jeom-Soo Kim;Sun-Young Lee;Jong-Seong Bae
    • Nanomaterials
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    • v.12 no.20
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    • pp.3605-3620
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    • 2022
  • Microtube-like porous carbon (MPC) and tube-like porous carbon-sulfur (MPC-S) composites were synthesized by carbonizing milkweed pappus with sulfur, and they were used as cathodes for lithium-sulfur batteries. The morphology and uniformity of these materials were characterized using X-ray powder diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy with an energy-dispersive X-ray analyzer, thermogravimetric analysis, and X-ray photoelectron spectrometry. The electrochemical performance of the MPC-S cathodes was measured using the charge/discharge cycling performance, C rate, and AC impedance. The composite cathodes with 93.8 wt.% sulfur exhibited a stable specific capacity of 743 mAh g-1 after 200 cycles at a 0.5 C.

Efficient polynomial exponentiation in $GF(2^m)$with a trinomial using weakly dual basis ($GF(2^m)$에서 삼항 기약 다항식을 이용한 약한 쌍대 기저 기반의 효율적인 지수승기)

  • Kim, Hee-Seok;Chang, Nam-Su;Lim, Jong-In;Kim, Chang-Han
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.8
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    • pp.30-37
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    • 2007
  • An exponentiation in $GF(2^m)$ is a basic operation for several algorithms used in cryptography, digital signal processing, error-correction code and so on. Existing hardware implementations for the exponentiation operation organize by Right-to-Left method since a merit of parallel circuit. Our paper proposes a polynomial exponentiation structure with a trinomial that is organized by Left-to-Right method and that utilizes a weakly dual basis. The basic idea of our method is to decrease time delay using precomputation tables because one of two inputs in the Left-to-Right method is fixed. Since $T_{sqr}$ (squarer time delay) + $T_{mul}$(multiplier time delay) of ow method is smaller than $T_{mul}$ of existing methods, our method reduces time delays of existing Left-to-Right and Right-to-Left methods by each 17%, 10% for $x^m+x+1$ (irreducible polynomial), by each 21%, 9% $x^m+x^k+1(1, by each 15%, 1% for $x^m+x^{m/2}+1$.

Absorbed and effective dose for periapical radiography using portable and wall type dental X-ray machines (이동형 구내방사선촬영기와 벽걸이 구내방사선촬영기로 촬영한 치근단 방사선촬영에서 환자의 흡수선량과 유효선량 평가)

  • Han, Won-Jeong
    • The Journal of Korean Academy of Prosthodontics
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    • v.50 no.3
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    • pp.184-190
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    • 2012
  • Purpose: The purpose of this study was to measure the absorbed dose and to calculate the effective dose for one periapical radiography using the portable and wall type dental X-ray machines. Materials and methods: Thermoluminescent chips were placed at 25 sites throughout the layers of the head and neck of a tissue-equivalent human skull phantom. The man phantom was exposed with the portable and wall type dental X-ray machines. For one periapical radiography taken by portable dental X-ray machine, the exposure setting was 60 kVp, 2 mA and 0.2 seconds, while for one periapical radiography taken by wall type dental X-ray machine, exposure setting was 70 kVp, 8 mA and 0.074 seconds. Absorbed dose measurements were performed and equivalent doses to individual organs were summed using ICRP 103 to calculate effective dose. Results: In the upper anterior periapical radiography using portable dental X-ray machine and in the lower posterior periapical radiography using both machines, the highest absorbed dose was recorded at the mandible body. The effective dose in upper anterior periapical radiography using portable and wall type dental X-ray machines was $4{\mu}Sv$, $2{\mu}Sv$, respectively. In the lower posterior periapical radiography, the effective dose for each portable and wall type dental X-ray machines was $6{\mu}Sv$, $2{\mu}Sv$. Conclusion: It was recommended that the operator use prudently potable dental X-ray machine because that the effective dose in the periapical radiography using wall type dental X-ray machine was lower than that in the periapical radiography using portable dental X-ray machine.

Basic Studies on the Breeding of Fiber Flax (Linum usitatissimum L.) in Korea (섬유용 아마(Linum usitatissimum L.)의 육종에 관한 기초적 연구)

  • Kyu-Yong Chung
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.19
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    • pp.83-99
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    • 1975
  • The earliness to flowering was completely dominant over the lateness, and the short plant height and stem length were partially dominant over the tall. The heavy stem weight, however, was recessive to the light. Heritability values for the flowering period, plant height, dry stem weight and fiber ratio were high, while those of days to initial flowering, stem length and fiber weight were low. Flowering period, plant height, stem weight, dry stem weight and fiber ratio were closely related to fiber weight or fiber yield. The selection index estimated jointly the plant height ($X_1$), dry stem weight($X_2$) and fiber weight($X_3$); that is 0.0020$X_1$-0.0047$X_2$-0.0181$X_3$, was the most efficient one for the selection practices. The plant height was the most reliable character for the increased genetic advances and the relative selection efficiences. Effects of locations and genotype-environment interactions were highly significant in most of the characters investigated.

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