• Korean Journal of Crystallography
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• v.15 no.2
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• pp.83-87
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• 2004

An organometallic complex. $Me_2Pt(PPh_2CH_2C(t-Bu)=N-N=CMe(2-py)-\kappa^2N,P)$ was synthesized from phosphinohydrazone $Ph_2PCH_2C(t-Bu)=NNH_2$, 2-acetylpyridine, and $[PtMe2({\mu}-SMe_2)]_2$. The molecular structure of this complex has been determined by X-ray diffraction. Crystallographic data: monoclinic, space group $P2_1/n,\;a=11.6926(7)\;{\AA},\;b=15.6607(19)\;{\AA},\; c=14.6125(6)\;{\AA},\;\beta=93.018(4)^{\circ},\;Z=4,\;V=2672.0(4)\;{\AA}^3$. The structure was solved by direct methods and refined by full-matrix least-squares methods to give a model with a reliability factor R = 0.0363 for 5238 reflections.

• Korean Journal of Crystallography
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• v.15 no.2
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• pp.88-92
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• 2004

An organometallic compound, $(C_{16}H_{21}B_{10}BrOSn)$, was synthesized from o-carborane, closo-1-[(methoxyl)methyl]-o-carborane $(HCab^o)$, and $SnMe_2Br_2$. The molecular structure of this complex has been determined by X-ray diffraction. Crystallographic data: orthorhombic, space group Pna2, a = 17.9292(15)$\AA$, b= 7.2066(4)$\AA$, c=13.0582(10)$\AA$, Z=4, V=1687.2(2) $\AA^3$. The structure was solved by direct methods and refined by full-matrix least-squares methods to give a model with a reliability factor R=0.0574 for 1724 reflections.

• Korean Journal of Crystallography
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• v.13 no.3_4
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• pp.158-164
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• 2002

Tetrahomodioxa p-phenylcalix(4)arene dihexylether(C/sub66/H/sub68/O/sub6/) has been synthesized and structurally characterized by X-ray diffraction. Reaction of tetrahomodioxa p-phenylcalix(4)arene with hexyl halide and NaH in DMF leads to the dihexyl derivatives, 7,13,21,27-tetraphenyl-29,31-dihexyloxy- 2,3,16,17-tetrahomo-3,17-dioxacalit(4)arenes. The crystal is orthorhombic, P2₁2₁2₁, a= 9.764(2), b=16.167(2), c=32.994(3) Å, V=5208(1) Å, Z= 4, Dc = 1.221 gcm/sup -3/. The structure was solved by direct methods and refined by full-matrix least squares. Refinement converged at R = 0.070 for 2009 observed reflections. This molecule has a C-1,2-alternate conformation with pseudo-centrosymmetry and has two pairs of opposite phenyl rings, which are approximately parallel to each other. The benzene rings A and B are up, and the rings C and D rings are down with respect to the plane of the macrocyclic ring.

• Polymer(Korea)
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• v.27 no.6
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• pp.549-554
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• 2003

Emeraldine salt of polyaniline-dodecylbenzenesulfdnic acid (PANI-DBSA) in organic solvents such as toluene and xylene was obtained by a direct one-step emulsion polymerization technique. When the molar ratio of DBSA to aniline monomer was 1.5:1, its solubility and electric property showed a maximum value and then the solid contents of PANI-DBSA was 8 wt% in toluene. The cast film of PANI-DBSA with no binder was obtained on glass or plastic substrates under ambient conditions. PANI solution can be also easily blended with polyurethane and polystyrene polymers in toluene. Improved electrical performance up to 5 S/cm was achieved with good light-transmittance up to 70% at 500 m thickness. They also showed more homogeneous morphology than that prepared with PANI-DBSA kom aqueous dispersion polymerization. The partially dispersed PANI-DBSA showed particles sizes of 50-400 m in organic solvents and their XRD pattern were observed from the powder sample.

• Food Science of Animal Resources
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• v.35 no.5
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• pp.707-713
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• 2015

Royal jelly has been widely used as a health supplement worldwide. However, royal jelly has been implicated in allergic reactions, and we developed a water-soluble royal jelly (WSRJ) without the allergy inducing protein. In this study, we aimed to identify the anti-melanogenic efficacy of WSRJ. B16F1 melanoma cells were first treated with 10 nM α-melanocyte stimulating hormone (α-MSH) and then with various doses of WSRJ. In addition, we investigated the mRNA and protein expression of melanogenesis-related genes such as tyrosinase, tyrosinase related protein-1 (TRP-1) and TRP-2 by reverse transcription-polymerase chain reaction and western blotting. WSRJ directly inhibited tyrosinase and cellular tyrosinase activity, which decreased melanin synthesis in α-MSH stimulated B16F1 melanoma cells a level comparable to that observed with arbutin. WSRJ decreased the mRNA and protein expressions of tyrosinase, TRP-1, and TRP-2, which was comparable to that observed with arbutin. WSRJ has strong anti-melanogenic activity, which invoice direct inhibition of tyrosinase enzyme activity and suppression of expression of melanogenesis related genes. Results from this study suggests that WSRJ is a potential candidate for the treatment of skin pigmentation.

• Journal of the Mineralogical Society of Korea
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• v.23 no.3
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• pp.191-197
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• 2010

Fine nickel metal powder of uniform morphology, narrow size distribution, and high purity was prepared from high purity metal solution. Slurry reduction method for the synthesis of metal powder was applied with a special interest in their fine and spherical shape. The products were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Well dispersed ultrafine nickel powder with the particle size range of 100~200 nm was produced from Ni-hydrazine precursor using hydrazine as a reductant for 90 min reaction in 4.5 M NaOH solution.

• International journal of advanced smart convergence
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• v.5 no.4
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• pp.15-20
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• 2016

When a virtual sound source for 3D auditory system is reproduced by a linear loudspeaker array, listeners can perceive not only the direction of the source, but also its distance. Control over perceived distance has often been implemented via the adjustment of various acoustic parameters, such as loudness, spectrum change, and the direct-to-reverberant energy ratio; however, there is a neglected yet powerful cue to the distance of a nearby virtual sound source that can be manipulated for sources that are positioned away from the listener's median plane. This paper address the problem of generating binaural signals for moving sources in closed or in open environments. The proposed perceptual enhancement algorithm composed of three main parts is developed: propagation, reverberation and the effect of the head, torso and pinna. For propagation the effect of attenuation due to distance and molecular air-absorption is considered. Related to the interaction of sounds with the environment, especially in closed environments is reverberation. The effects of the head, torso and pinna on signals that arrive at the listener are also objectives of the consideration. The set of HRTF that have been used to simulate the virtual sound source environment for 3D auditory system. Special attention has been given to the modelling and interpolation of HRTFs for the generation of new transfer functions and definition of trajectories, definition of closed environment, etc. also be considered for their inclusion in the program to achieve realistic binaural renderings. The evaluation is implemented in MATLAB.

• Journal of Korean Academy of Nursing
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• v.50 no.4
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• pp.513-522
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• 2020

Purpose: This study aimed to utilize concept analysis to obtain a better understanding of the concept of "continuity of care" in chronic diseases. Methods: The concept of continuity of care was analyzed using the Walker and Avant method. Covering literature in English from 1930 to 2018, the data sources included CINAHL Complete, Academic Search Complete, MEDLINE, PsyARTICLES, Health Source: Nursing/Academic Edition, Google Scholar, Science Direct, and the Cochrane Library. Results: A comprehensive definition of concept of continuity of care was developed based on a systematic search and synthesis. The key defining attributes were identified as (a) care over time, (b) the relationship between an individual patient and a care team, (c) information transfer, (d) coordination, and (e) meeting changing needs. The antecedents of continuity of care were having a chronic disease, inexperienced with disease management, a poorly coordinated healthcare system, and medical care limitations. The consequences of continuity of care were decreasing hospital admissions, reducing costs, reducing emergency room visits, improving the quality of life, improving patient satisfaction, and delivering good healthcare. Conclusion: The thorough concept analysis provides insight into the nature of "continuity of care" in chronic diseases and also helps ground the concept in healthcare.

• Journal of Periodontal and Implant Science
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• v.26 no.2
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• pp.376-395
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• 1996

The neuropeptide substance P(SP) has been recognized to modulate immune systems, with close proximity between peptidergic sensory nerve endings and immune cells. These include the macrophage and neutrophil activation, IL-2 production in T cell, augmentation of Ig synthesis, mast cell degranulation, $PGE_2$ and collagenase secretion in synoviocytes. In this study I examined SP-induced various biological activities such as antimicrobial action, cytokine production, and mast cell degranulation in the presence or absence of other inflammatory cell activators. Antimicrobial studies showed that undifferentiated HL-60 cells were not affected by SP. However, SP significantly enhanced antimicrobial action of TPA-treated or dbcAMP-treated HL-60 cells which had been differentiated into PMN or macrophage/monocyte. I could not find synergistic relationship between SP and LPS in parallel experiments of the above. SP did not induce IL-l production from murine macrophage cell line RAW264.7 whether costimulated with LPS or not. Mast cell degranulation was occured only when stimulated with high dose ($10^{-5}M$) of SP and the degree of this activation was slightly reduced by simultaneous application of $MIP-1{\alpha}$. In addition, CGRP which is known to be a common coexisting neuropeptide with SP within specific fibers did not augment the function of SP on mast cell degranulation. These results suggest that immunoregulatory activities of SP could be mediated through direct upregulation of various functions of immune cells and also upregulation of responsiveness of immune cells to other immune activators.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.12
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• pp.2628-2635
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• 2010

This paper analyzes the detection probability of FMCW (Frequency Modulated Continuous Wave) radar based on Doppler frequency and analog-digital converter bit and designs and implements signal processing part of FMCW radar. For performance evaluation, the FMCW radar system consists of a transmitted part and a received part and uses AWGN channel. The system model is verified through analysis and simulation. Frequency offset occurs in the received part caused by the mismatching between the received signal and the reference signal. In case of Doppler frequency less than about 38KHz, performance degradation of detection does not occur in FMCW radar with 75cm resolution The analog-digital converter needs at least 6 bit in order not to degrade the detection probability. And, we design and implement digital signal processing part based on DDS chip of digital transmitted signal generator for FMCW radar.