• 한국재료학회지
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• 제25권7호
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• pp.358-363
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• 2015

We present an excellent detection for nitrogen monoxide (NO) gas using polycrystalline ZnO wire-like films synthesized via a simple method combined with sputtering of Zn metallic films and subsequent thermal oxidation of the sputtered Zn nanowire films in dry air. Structural and morphological characterization revealed that it would be possible to synthesize polycrystalline hexagonal wurtzite ZnO films of a wire-like nanostructure with widths of 100-150 nm and lengths of several microns by controlling the sputtering conditions. It was found from the gas sensing measurements that the ZnO wire-like thin film gas sensor showed a significantly high response, with a maximum value of 29.2 for 2 ppm NO at $200^{\circ}C$, as well as a reversible fast response to NO with a very low detection limit of 50 ppb. In addition, the ZnO wire-like thin film gas sensor also displayed an NO-selective sensing response for NO, $O_2$, $H_2$, $NH_3$, and CO gases. Our results illustrate that polycrystalline ZnO wire-like thin films are potential sensing materials for the fabrication of NO-sensitive high-performance gas sensors.

• 한방안이비인후피부과학회지
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• 제25권2호
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• pp.83-91
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• 2012

Background and Objective : Erythema nodosum-like lesions in patients with Behcet's disease is a reactive dermatosis that occurs in response to various stimuli, such as bacterial, fungal and viral infections, drugs and malignancies. We observed and treated a case of erythema nodosum-like lesions with Behcet's disease. We present this case because there were no former reports of erythema nodosum-like lesions with Behcet's disease treated by herbal medicine. Methods : The patient was a 28-year-old. The chief complains were erythema, nodose, edema, burning sensation, tenderness on both legs, forearms and feet, arthralgia and genital ulcers. She was treated with Wolbi-Tang for eleven days. We diagnosed the medication according to the results of manual abdominal examination of the patient. We used the Visual Analogue Scale(VAS). Results : After the treatment the grade of VAS was decreased and clinical symptoms were improved. Conclusions : Wolbi-Tang can be used on the treatment of erythema nodosum-like lesions with Behcet's disease.

• 한국정보시스템학회지:정보시스템연구
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• 제32권4호
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• pp.69-94
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• 2023

Purpose Social networking service (SNS) platforms employ distinct networking strategies to meet the varying needs of their users, resulting in divergent sets of technological functionalities offered by each platform. Consequently, unique features on various SNSs give rise to distinct social issues. Moreover, the available technical coping mechanisms for users vary significantly across platforms. Design/methodology/approach Therefore, this study analyzes the factors affecting technical coping intention based on technical functions of SNSs for users exposed to cybercrime, such as sexual harassment. We divide coping intention into active and passive coping intention. Furthermore, this research focuses on trust as an antecedent of coping intention and verifies how human and system-like trust affects two coping intentions in different directions. Findings Findings reveal that system-like trust significantly affects both active and passive coping intention as a belief in whether the technology will work properly. However, in the case of human-like trust, trust in the platform provider was found to negatively affect passive coping, which is considered unsocialized behavior on SNS platforms. Therefore, both human-like and system-like trust for the platform must be appropriately applied to cope with the problem while activating the platform.

• Advanced Composite Materials
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• 제18권4호
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• pp.315-326
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• 2009

PCC (precipitated calcium carbonate) and ground calcium carbonate have been widely used in alkaline papermaking. Unfortunately, although increasing filler level in papers can improve the paper properties such as brightness, opacity, stiffness gloss, smoothness, porosity, and printability, as well as decrease cost, some strength of the paper is negatively affected. In this research, needle-like aragonite was synthesized using $Ca(OH)_2$ and $CO_2$ as reactants in the presence of $MgCl_2$ and characterized with scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The physical and optical properties of the paper handsheets containing these needle-like aragonite fillers were evaluated. Results indicated that tensile strength, Z-direction tensile strength and folding endurance of the paper were improved by the needle-like aragonite crystals compared to the paper using commercial PCC (precipitated calcium carbonate) as filler. The stiffness of the paper handsheet on the machine direction was increased, but no evident difference in the cross direction was found. The improvement of paper strength mainly resulted from the twining effect between the aragonite whiskers and paper fibers. The optical properties of the paper were slightly decreased with the use of the needle-like aragonites compared to commercial PCC. These results suggest that paper cost can be decreased by increasing the content of needle-like aragonite filler while paper strength will not be decreased compared to PCC filler.

• 한국재료학회지
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• 제28권6호
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• pp.324-329
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• 2018

Needle-like NiO protecting layers on NiCrAl alloy foam, used as support for hydrogen production, are introduced through electroplated Ni and subsequent microwave annealing. To improve the stability of the NiCrAl alloy foam, oxygen concentration of microwave annealing to form a needle-like NiO layer with good chemical stability and corrosion resistance is controlled in a range of 20 and 50 %. As the oxygen concentration increases to 50 %, needle-like NiO forms a dense coating layer on the NiCrAl alloy foam; this layer formation can be attributed to accelerated growth of the (200) plane. In addition, the increased oxygen concentration causes increased NiO/Ni ratio of the resultant coating layer on NiCrAl alloy foam due to improved rate of the oxidation reaction. As a result, the introduction of dense needle-like NiO layers formed at 50 % oxygen concentration improves the chemical stability of the NiCrAl alloy foam by protecting the direct electrochemical reaction between the electrolyte and the foam. Thus, needle-like NiO can be proposed as a superb protecting layer to improve the chemical stability of NiCrAl alloy form.

• Asian Pacific Journal of Cancer Prevention
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• 제15권21호
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• pp.9379-9383
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• 2014

Background: Pathologic complete response (pCR) is one of the most important target end-points of neoadjuvant chemotherapy (NACT) in patients with breast cancer (BC). In present study, we aimed to investigate the relationship between molecular subtypes and NACT in patients with BC. Materials and Methods: Using the Akdeniz University database, 106 patients who received NACT for operable breast cancer were retrospectively identified. Prognostic factors before and after NACT were assessed. According to the molecular subtypes, molecular shifting after NACT and tumoral and nodal response to NACT were analyzed. Results: The distribution of subtypes was: Luminal A, 28.3% (n=30); Luminal B, 31.1% (n=33); HER2-like, 24.5% (n=26); and basal like/triple negative (BL/TN), 16.0% (n=17). According to molecular subtypes, pCR rates in both breast and axillary were 0%, 21.4%, 36.4% and 27.3% for luminal A, luminal B, HER2-like and BL/TN, respectively (p=0.018). Molecular subtype shifting was mostly seen in luminal A type (28.6%) after the NACT. The pCR rate in breast and axillary was significantly higher in patients with HER2-like type BC. Conclusions: In patients with HER-2 like type BC, NACT may be offered in early stages. Additionally, due to molecular shifting, adjuvant treatment schedule should be reviewed again, especially in the luminal A group.

• Biomolecules & Therapeutics
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• 제21권6호
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• pp.447-453
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• 2013

Chondroitin sulfate proteoglycan (CSPG) inhibits neurite outgrowth of various neuronal cell types, and CSPG-associated inhibition of neurite outgrowth is mediated by the Rho/ROCK pathway. Mesenchymal stromal/stem cells (MSCs) have the potential to differentiate into neuron-like cells under specific conditions and have been shown to differentiate into neuron-like cells by co-treatment with the ROCK inhibitor Y27632 and the hypoxia condition mimicking agent $CoCl_2$. In this study, we addressed the hypothesis that a ROCK inhibitor might be beneficial to regenerate neurons during stem cell therapy by preventing transplanted MSCs from inhibition by CSPG in damaged tissues. Indeed, dose-dependent inhibition by CSPG pretreatment was observed during morphological changes of Wharton's jelly-derived MSCs (WJ-MSCs) induced by Y27632 alone. The formation of neurite-like structures was significantly inhibited when WJ-MSCs were pre-treated with CSPG before induction under Y27632 plus $CoCl_2$ conditions, and pretreatment with a protein kinase C inhibitor reversed such inhibition. However, CSPG treatment resulted in no significant inhibition of the WJ-MSC morphological changes into neuron-like cells after initiating induction by Y27632 plus $CoCl_2$. No marked changes were detected in expression levels of neuronal markers induced by Y27632 plus $CoCl_2$ upon CSPG treatment. CSPG also blocked the morphological changes of human bone marrow-derived MSCs into neuron-like cells under other neuronal induction condition without the ROCK inhibitor, and Y27632 pre-treatment blocked the inhibitory effect of CSPG. These results suggest that a ROCK inhibitor can be efficiently used in stem cell therapy for neuronal induction by avoiding hindrance from CSPG.

• Animal cells and systems
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• 제4권2호
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• pp.181-186
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• 2000

The expression of $p21^{WAF1/ClP1/SDl1}$, one of the cyclin-dependent kinase inhibitors, is regulated by a variety of transcription factors including p53 and STAT. Heat shock induces the expression of p21 in a temperature- and time-dependent manner. Although the p21 induction by heat shock has been reported to be controlled by p53, a p53-independent mechanism Is also involved. To understand the p53-independent regulation of heat shock-induced p21 expression, we searched the promoter region of p21 gene and found one or two heat shock element (HSE)-like sequences in human, rat, and mouse. Electromobility shift assay (EMSA) showed that heat shock factor (HSF) could bind to these HSE-like sequences In response to heat shock, even though to a lesser extent than to HSE. In addition, p21 promoter deletion analysis revealed that heat shock activated a p21 deletion promoter construct containing the HSE-like sequences but lacking p53-binding sites, but not a promoter construct containing neither HSE-like sequences nor the p53-responsive element. Furthermore, the p21 induction by heat shook was significantly inhibited in confluent cells in which heat shock-induced HSF activation was reduced. These results suggest that the transcriptional regulation of p21 by heat shock may be mediated through activation and binding to HSE-like sequences of HSF.

• 한국물환경학회지
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• 제37권5호
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• pp.344-354
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• 2021

Optical methods such as UV and fluorescence spectrophotometers can be applied not only in the qualitative analysis of dissolved organic matter (DOM), but also in real-time quantitative DOM monitoring for wastewater and natural water. In this study, we measure the UV₂₅₄ and fluorescence excitation emission spectra for a sewage treatment plant influent and effluent, and river water before and after sewage effluent flows into the river to examine the composition and origin of DOM. In addition, a correlation analysis between quantified DOM characteristics and dissolved organic carbon (DOC) was conducted. Based on the fluorescence excitation emission spectra analysis, it was confirmed that the protein-type tryptophan-like DOM was the dominant substance in the influent, and that the organic matter exhibited relatively more humic properties after biological treatment. However, DOM in river water showed the fluorescence characteristics of terrestrial humic-like and algal tyrosine-like (protein-like) organic matter. In addition, a correlation analysis was conducted between the DOC and optical indices such as UV₂₅₄, the fluorescence intensity of protein-like and humic-like organic matter, then DOC prediction models were suggested for wastewater and river monitoring during non-rainfall and rainfall events. This study provides basic information that can improve the understanding of the contribution of DOC concentration by DOM components, and can be used for organic carbon concentration management in wastewater and natural water.

• Journal of the Korean Statistical Society
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• 제8권2호
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• pp.139-163
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• 1979

Utilization of the aggregation concept applied in economics has been a traditional way of describing the state of an economic system and of predicting the future economic conditions. In addition, certain aggregate variables have also played a crucial role as indicators of the business cycle. Quick examples would be the price index, the productivity changes, the industrial production index, GNP, and so on. The methods of aggregation could be either simple summations, like GNP, or sophisticated weighted average, like the price index.