• Nuclear Medicine and Molecular Imaging
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• v.43 no.5
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• pp.451-458
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• 2009

Purpose: Optical molecular luminescence imaging is widely used for detection and imaging of bio-photons emitted by luminescent luciferase activation. The measured photons in this method provide the degree of molecular alteration or cell numbers with the advantage of high signal-to-noise ratio. To extract useful information from the measured results, the analysis based on a proper quantification method is necessary. In this research, we propose a quantification method presenting linear response of measured light signal to measurement time. Materials and Methods: We detected the luminescence signal by using lab-made optical imaging equipment of animal light imaging system (ALIS) and different two kinds of light sources. One is three bacterial light-emitting sources containing different number of bacteria. The other is three different non-bacterial light sources emitting very weak light. By using the concept of the candela and the flux, we could derive simplified linear quantification formula. After experimentally measuring light intensity, the data was processed with the proposed quantification function. Results: We could obtain linear response of photon counts to measurement time by applying the pre-determined quantification function. The ratio of the re-calculated photon counts and measurement time present a constant value although different light source was applied. Conclusion: The quantification function for linear response could be applicable to the standard quantification process. The proposed method could be used for the exact quantitative analysis in various light imaging equipments with presenting linear response behavior of constant light emitting sources to measurement time.

• Applied Chemistry for Engineering
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• v.17 no.1
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• pp.87-92
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• 2006

The steam reforming of methane over Ru-promoted $Ni/Al_2O_3$ was carried out. Compared with $Ni/Al_2O_3$, which needs pre-reduction by $H_2$, $Ru/Ni/Al_2O_3$ catalysts exhibited relatively higher activity than conventional $Ni/Al_2O_3$. According to $H_2-TPR$ of reduced or used catalysts and $CH_4-TPR$, it was revealed that the reduction of $RuO_x$ by $CH_4$ decomposition begins at a lower temperature ($220^{\circ}C$) and the reduced Ru facilitates the reduction of NiO, and leads to self-activation. To improve metal dispersion, the catalyst was soaked in 7 M aqueous $NH_4OH$ for 2 h at $45^{\circ}C$ while stirring. As a result, $Ru/Ni/Al_2O_3$ catalysts with aqueous $NH_4OH$ treatment have higher activity, larger metal surface area (by $H_2$-chemisorption), and small particle size (by XRD and XPS). It is noted that the amount of noble metal could be reduced by aqueous $NH_4OH$ treatment.

• Korean Journal of Acupuncture
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• v.30 no.3
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• pp.161-170
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• 2013

Objectives : Our study aimed to investigate the sustained effects of sham (SHAM) and verum acupuncture (ACUP) into the post-stimulus resting state. Methods : In contrast to previous studies, in order to define the changes in resting state induced by acupuncture, changes were evaluated with a multi-method approach by using regional homogeneity (ReHo) and amplitude of low frequency fluctuation (ALFF). Twelve healthy participants received SHAM and ACUP stimulation right GB34 (Yanglingquan) and the neural changes between post- and pre-stimulation were detected. Results : The following results were found; in both ReHo and ALFF, the significant foci of; left and right middle frontal gyrus, left medial frontal gyrus, left superior frontal gyrus, and right posterior cingulate cortex, areas that are known as a default mode network, showed increased connectivity. In addition, in ReHo, but not in ALFF, brain activation changes in the insula, anterior cingulate cortex, and the thalamus, which are associated with acupuncture pain modulation, were found. Conclusions : In this study, results obtained by using ReHo and ALFF, showed that acupuncture can modulate the post-stimulus resting state and that ReHo, but not ALFF, can also detect the neural changes that were induced by the acupuncture stimulations. Although more future studies with ReHo and ALFF will be needed before any firm conclusions can be drawn, our study shows that particularly ReHo could be an interesting method for future clinical neuroimaging studies on acupuncture.

• Journal of the Korean Magnetics Society
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• v.15 no.2
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• pp.67-75
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• 2005

For th aim of lightweight microwave absorbers, conductive and magnetic microspheres are fabricated by plating of Co films on hollow ceramic microspheres of low density. Metal plating was carried out in a two-step electroless plating process (pre-treatment of activation and plating). Uniform coating of the film with about $2{\~}3{\cal}um$ thickness was identified by SEM. High-frequency magnetic and microwave absorbing properties were determined in the rubber composites containing the Co-coated microspheres. Due to conductive and ferromagnetic behavior of the Co thin films, high dielectric constant and magnetic loss can be obtained in the microwave frequencies. Due to those electromagnetic properties, high absorption rate (25 dB) and thin matching thickness ($2.0{\~}2.5{\cal}mm$) are predicted in the composite layers containing the metal-coated microspheres of low density (about 0.84 g/cc) for the electromagnetic radiation in microwave frequencies.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.98-104
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• 2011

We investigated inhibitory effects of ginseng extracts against compound 48/80-induced responses in rat peritoneal mast cells. Initially, we optimized extraction condition with various temperature and time for recovery of high saponin contents in extracts. Using a primary rat peritoneal mast cells, we examined whether ginseng extracts inhibit compound 48/80-induced histamine release form rat mast cells. High red ginseng-spercific saponin containing extracts were recovered at $85^{\circ}C$ for 48 hr, and had no cytotoxicity with relatively high dose of extracts on rat peritoneal mast cells(<0.5 mg/ml). For examine of ameliorate effects of mast cells responses by ginseng extract, we pre-treated the extracts or saline to mast cells and treated compound 48/80. In results, compound 48/80 treatment was increased histamine release (approximately 30%) from mast cells than normal group, whereas ginseng treatment was completely inhibited histamine release. These results suggested that ginseng extracts inhibits the compound 48/80-induced mast cell activation, and ginseng extracts is a candidate for effective therapeutic tools of allergic diseases.

• Korean Chemical Engineering Research
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• v.44 no.2
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• pp.160-165
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• 2006

A Pd-Cu-Ni alloyed hydrogen membrane has fabricated on porous nickel support formed by nickel powder. Porous nickel support made by sintering shows a strong resistance to hydrogen embrittlement and thermal fatigue. Plasma surface modification treatment is introduced as pre-treatment process instead of conventional HCl wet activation. Nickel was electroplated to a thickness of $2{\mu}m$ in order in to fill micropores at the nickel support surface. Palladium and copper were deposited at thicknesses of $4{\mu}m$ and $0.5{\mu}m$, respectively, on the nickel coated support by DC sputtering process. Subsequently, copper reflow at $700^{\circ}C$ was performed for an hour in $H_2$ ambient. And, as a result PdCu-Ni composite membrane has a pinhole-free and extremely dense microstructure, having a good adhesion to the porous nickel support and infinite hydrogen selectivity in $H_2/N_2$ mixtures.

• Korean Journal of Construction Engineering and Management
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• v.17 no.5
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• pp.108-119
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• 2016

Since the introduction of the converted accident rate in Pre-Qualification(PQ) process in 1992, the safety evaluation system has contributed to a reduction of construction accidents and development of the safety management system in public construction projects. As the comprehensive evaluation method the government plans to introduce includes the indicators 'accident rate' and 'death rate per 10,000 workers', the influences on the safety evaluation in the bidding process would be broader in public sector construction projects. However, the current safety evaluation system is operated by different estimating standards in the bidding process. At this point, a study of improvement on the safety evaluation index is required to review its current conditions and to propose its efficient operating method. Therefore, the purpose of this study is to analyze problems of the current safety evaluation system through the questionnaire survey on the qualified workers in construction safety management and to propose an improvement plan for the problems noticed. Our results suggest the standards of the unified process for the safety evaluation index, the size of construction firms needed for accident rate estimation, and the improvement plan for unreported accidents. The proposed improvement plan enables the reasonable estimation and efficient operation of the safety evaluation index, and further, it would contribute to reducing construction accidents through the activation of voluntary safety management by construction firms.

• BMB Reports
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• v.46 no.4
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• pp.201-206
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• 2013

Sulforaphane [1-isothiocyanato-4-(methylsulfinyl)-butane] is an isothiocyanate found in some cruciferous vegetables, especially broccoli. Sulforaphane has been shown to display anti-cancer properties against various cancer cell lines. Matrix metalloproteinase-9 (MMP-9), which degrades the extracellular matrix (ECM), plays an important role in cancer cell invasion. In this study, we investigated the effect of sulforaphane on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion in MCF-7 cells. TPA-induced MMP-9 expression and cell invasion were decreased by sulforaphane treatment. TPA substantially increased NF-${\kappa}B$ and AP-1 DNA binding activity. Pre-treatment with sulforaphane inhibited TPA-stimulated NF-${\kappa}B$ binding activity, but not AP-1 binding activity. In addition, we found that sulforaphane suppressed NF-${\kappa}B$ activation, by inhibiting phosphorylation of $I{\kappa}B $ in TPA-treated MCF-7 cells. In this study, we demonstrated that the inhibition of TPA-induced MMP-9 expression and cell invasion by sulforaphane was mediated by the suppression of the NF-${\kappa}B$ pathway in MCF-7 cells.

• The Korea Journal of Herbology
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• v.35 no.4
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• pp.51-60
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• 2020

Objective : The objective of this study was to demonstrate the effect of Persicae Semen (PS) in DNCB-induced atopic dermatitis mouse and HaCaT cell. Methods : The BALB/c mice were divided into four groups. To develop atopic dermatitis, 200 ㎕ of 1 and 0.5% DNCB solution was put on the back of mice in the Control group, the PS-Low group and the PS-High group once a day. After application of DNCB, 200 ㎕ of the PS extract was also treated. The Normal group was given PBS. The mice dorsal skin was stained with Masson's trichrome, H&E, and toluidine blue to evaluate the thickness of the epidermis and dermis, infiltration of eosinophils and mast cells respectively. ELISA was applied to measure the serum level of IgE and IL-6. Toxicity of PS was measured by MTS assay in HaCaT cell. To investigate the effects of PS on HaCaT cells, cells were pre-treated with PS for 1h, and then stimulated with TNF-α and IFN-γ. After 24 hours, the expression of TARC was analyzed using RT-PCR. Results : PS not only significantly diminished the thickness of the epidermis and dermis, but also reduced the infiltration of eosinophil and mast cell in skin lesion. PS also reduced the serum IgE and IL-6 level which plated important roles in the atopic dermatitis. The expression of TARC was decreased significantly in TNF-α/IFN-γ stimulated HaCaT cell. Conclusion : These results suggest that PS may be effective in alleviating the atopic dermatitis induced by DNCB and inflammation by TNF-α/IFN-γ.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.2
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• pp.123-129
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• 2017

This paper proposes a new nonnegative matrix factorization (NMF) based direction-of-arrival (DOA) estimation method for multiple sound sources using a dual microphone array. First of all, sound signals coming from the dual microphone array are segmented into consecutive analysis frames, and a steered-response power phase transform (SRP-PHAT) beamformer is applied to each frame so that stereo signals of each frame are represented in a time-direction domain. The time-direction outputs of SRP-PHAT are stored for a pre-defined number of frames, which is referred to as a time-direction block. Next, In order to estimate DOAs robust to noise, each time-direction block is normalized along the time by using a block subtraction technique. After that, an unsupervised NMF method is applied to the normalized time-direction block in order to cluster the directions of each sound source in a multiple sound source environments. In particular, the activation and basis matrices are used to estimate the number of sound sources and their DOAs, respectively. The DOA estimation performance of the proposed method is evaluated by measuring a mean absolute error (MAE) and the standard deviation of errors between the oracle and estimated DOAs under a three source condition, where the sources are located in [$-35{\circ}$, 5m], [$12{\circ}$, 4m], and [$38{\circ}$, 4.m] from the dual microphone array. It is shown from the experiment that the proposed method could relatively reduce MAE by 56.83%, compared to a conventional SRP-PHAT based DOA estimation method.