• Journal of Electrical Engineering and Technology
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• v.13 no.5
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• pp.1886-1900
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• 2018

This paper proposes a confronting feedback control structure and controllers for positive output elementary super lift Luo converters (POESLLCs) working in discontinuous conduction mode (DCM). The POESLLC offers the merits like high voltage transfer gain, good efficiency, and minimized coil current and capacitor voltage ripples. The POESLLC working in DCM holds the value of not having right half pole zero (RHPZ) in their control to output transfer function unlike continuous conduction mode (CCM). Also the DCM bestows superlative dynamic response, eliminates the reverse recovery troubles of diode and retains the stability. The proposed control structure involves two controllers respectively to control the voltage (outer) loop and the current (inner) loop to confront the time-varying ON/OFF characteristics of variable structured systems (VSSs) like POESLLC. This study involves two different combination of feedback controllers viz. the proportional integral controller (PIC) plus sliding mode controller (SMC) and the fuzzy logic controller (FLC) plus SMC. The state space averaging modeling of POESLLC in DCM is reviewed first, then design of PIC, FLC and SMC are detailed. The performance of developed controller combinations is studied at different working states of the POESLLC system by MATLAB-Simulink implementation. Further the experimental corroboration is done through implementation of the developed controllers in PIC 16F877A processor. The prototype uses IRF250 MOSFET, IR2110 driver and UF5408 diodes. The results reassured the proficiency of designed FLC plus SMC combination over its counterpart PIC plus SMC.

• Journal of Microbiology and Biotechnology
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• v.18 no.7
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• pp.1278-1285
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• 2008

The intestinal epithelial cell (IEC) layer of the intestinal tract makes direct contact with a number of microbiota communities, including bacteria known to have deleterious health effects. IECs possess innate protective strategies against pathogenic challenge, which primarily involve the formation of a physicochemical barrier. Intestinal tract mucins are principal components of the mucus layer on epithelial surfaces, and perform a protective function against microbial damage. However, little is currently known regarding the interactions between probiotics/pathogens and epithelial cell mucins. The principal objective of this study was to determine the effects of Lactobacillus on the upregulation of MUC2 mucin and the subsequent inhibition of E. coli O157:H7 attachment to epithelial cells. In the current study, the attachment of E. coli O157:H7 to HT-29 intestinal epithelial cells was inhibited significantly by L. acidophilus A4 and its cell extracts. It is also important to note that the expression of MUC2 mucin was increased as the result of the addition of L. acidophilus A4 cell extracts (10.0 mg/ml), which also induced a significant reduction in the degree to which E. coli O157:H7 attached to epithelial cells. In addition, the mRNA levels of IL-8, IL-1$\beta$, and TNF-$\alpha$ in HT-29 cells were significantly induced by treatment with L. acidophilus A4 extracts. These results indicate that MUC2 mucin and cytokines are important regulatory factors in the immune systems of the gut, and that selected lactobacilli may be able to induce the upregulation of MUC2 mucin and specific cytokines, thereby inhibiting the attachment of E. coli O157:H7.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.10
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• pp.1328-1336
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• 2014

This paper proposes Power System Health Index(PSHI) newly. The paper describes several kind of power system health indices based on two main categories, which are adequacy and security. In adequacy, four kinds of health indices of Frequency, Voltage, Reserve(Operating Reserve Power and Frequency Regulation Reserve Power) and Overload of lines and transformers are proposed. In security, four kinds of health indices of Voltage(154kV, 345kV and 765kV), Overload of lines and transformers, Power flow constraint among areas and SPS are proposed. All indices are mapped with three domains, which are indicated as Health, Margin and Risk, defined with expert interview. While domains of health, margin and risk is defined similar with the conventional well being analysis of power system. The criterion of the domains is proposed using an interview with expert operators and practical reliability codes in Korea. The several kinds of health index functions, which are linear ratio, piecewise linear ration and reverse ratio function etc. are developed in this paper. It will be expected that the developed health indices can help operators to control power system more successfully and also prevent power system from accident as like as black out in future because operator can make a decision immediately based on more easily visual information of system conditions from too much indices acquisition of complex power system.

• The KIPS Transactions:PartC
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• v.9C no.2
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• pp.181-188
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• 2002

There are recently a lot of inconvenience because every client should be set to the proxy server on the browser in order to control the access by means of the client authentication in the proxy server. The client authentication technology using the transparency cache in this paper will be transparently used for every user in the internet which option of the authentication function is simply set in the cache server. In addition, the administrator will get the benefit since he can control the traffic of each client and strengthen the security. And also, this system is expected to use in the eCRM deeply rotated to the tendency of the client in the field of the e-commerce like shopping mall in the internet since the administrator can monitor the pattern of the client using the internet. This technique can be applied to the company affiliated research center, the EC website, and the military where it is essential for the tight security even though there are no additional security devices.

• The Plant Pathology Journal
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• v.36 no.6
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• pp.618-627
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• 2020

Although limited progress have been made about pathogen system of Hibiscus rosa-sinensis and Hibiscus latent Fort Pierce virus (HLFPV), interaction between plant host and pathogen remain largely unknown, which led to deficiency of effective measures to control disease of hibiscus plants caused by HLFPV. In this study, infection of HLFPV in Hibiscus rosa-sinensis was firstly confirmed for the first time by traditional electron microscopy, modern reverse transcription polymerase chain reaction and RNA-seq methods in China (HLFPV-Ch). Sequence properties analyzing suggested that the full-length sequences (6,465 nt) of HLFPV-Ch had a high sequence identity and a similar genomic structure with other tobamoviruses. It includes a 5'-terminal untranslated region (UTR), followed by four open reading frames encoding for a 128.5-kDa replicase, a 186.5-kDa polymerase, a 31-kDa movement protein, 17.6-kDa coat protein, and the last a 3'-terminal UTR. Furthermore, HLFPV-Ch-derived virus-derived siRNAs (vsiRNAs) ant its putative target genes, reported also for the first time, were identified and characterized from disease Hibiscus rosa-sinensis through sRNA-seq and Patmatch server to investigate the interaction in this pathogen systems. HLFPV-Ch-derived vsiRNAs demonstrated several general and specific characteristics. Gene Ontology classification revealed predicted target genes by vsiRNAs are involved in abroad range of cellular component, molecular function and biological processes. Taken together, for first time, our results certified the HLFPV infection in China and provide an insight into interaction between HLFPV and Hibiscus rosa-sinensis.

• Molecules and Cells
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• v.21 no.1
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• pp.153-160
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• 2006

Virus-induced gene silencing (VIGS) is an attractive reverse-genetics tool for studying gene function in plants. We showed that silencing of a phytoene desaturase (PDS) gene is maintained throughout TRV-PDS-inoculated tomato plants as well as in their flowers and fruit and is enhanced by low temperature ($15^{\circ}C$) and low humidity (30%). RT-PCR analysis of the PDS gene revealed a dramatic reduction in the level of PDS mRNA in leaves, flowers and fruits. Silencing of PDS results in the accumulation of phytoene, the desaturase substrate. In addition, the content of chlorophyll a, chlorophyll b and total chlorophyll in the leaves of PDS-silenced plants was reduced by more than 90%. We also silenced the LeEIN2 gene by infecting seedlings, and this suppressed fruit ripenning. We conclude that this VIGS approach should facilitate large-scale functional analysis of genes involved in the development and ripening of tomato.

• The Korean Journal of Nuclear Medicine
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• v.21 no.2
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• pp.151-154
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• 1987

Total 114 patients were studied prospectively with radioiodine uptake (RAIU) and $^{99m}TcO_4^-$ thyroid scan to design a very simple, rapid and inexpensive method measuring the thyroid uptake on thyroid scan. After the RAIU was obtained at 24 hours after P.O. of $^{131}I$, Thyroid scan was performed at 20 minutes after LV. of $^{99m}TcO_4^-$ and the bilateral salivary glands were included in the scan field. Pinhole collimated and computer assisted gamma camera was used. Three regions of interest were set on each salivary gland and on the thyroid by automatic edge detection method. Mean counts per pixel were calculated for each ROI and the salivary-thyroid ratio (STR) was defined as; $$STR(%)=\frac{Mean\;counts\;per\;pixel\;of\;salivary\;glands\;(KC)}{Mean\;counts\;per\;pixel\;of\;thyroid\;gland\;(KC)}\times100$$ 114 cases consisted of 41 normal, 55 hyperthyroid and 18 hypothyroid patients and correlation between the STR and the RAID were evaluated in total and each group. The STR and the RAID showed reverse linear regression in 114 cases (r= -0.8, P=0) and closer correlation was shown in hyperthyroid group (r= -0_9, p=0). Mean STR in normal group was 47.6%. In predicting the RAID by STR, sensitivity and specificity were 88.3% and 64.9% in 114 cases and 95.3% and 83.3% in hyperthyroid group. It is recommended that the STR be used in place of the RAID giving same information at saving time, money and radiation exposure.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.1
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• pp.67-75
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• 2013

The flow stress of zircaloy-4 used in the spacer grid supporting a nuclear fuel rod was determined by the Johnson-Cook model, and model parameters were determined using reverse engineering. Parameters such as A, B, n and $\dot{\varepsilon}_0$ were determined by the tensile test result. To obtain the parameters C and m, a slot milling test and numerical simulation were performed. The objective functions were defined as the difference between the experimental and the simulation results, and then, the parameters were determined by minimizing the objective function. To verify the validity of the determined parameters, cross-verification for each case was conducted through a shearing test and simulation. The results tend to show agreement with the experimental results, such as the features of sheared edges and maximum punch force, with the correlation coefficients exceeding at least 0.97.

• Annals of dermatology
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• v.30 no.6
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• pp.645-652
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• 2018

Background: Adiponectin, an adipokine secreted from adipocytes, affects energy metabolism and also shows anti-diabetic and anti-inflammatory properties. Recent studies have reported that adiponectin plays a role in regulating skin inflammation. Objective: This study aimed to investigate the effect of adiponectin on the expression of filaggrin (FLG) in normal human epidermal keratinocytes (NHEKs). Methods: NHEKs were serum-starved for 6h before being treated with adiponectin. Afterward, cell viability was assessed by MTT assay. We also treated with calcium, interleukin (IL)-4, and IL-13 to provide positive and negative comparative controls, respectively. Gene mRNA expression was quantified using real time reverse transcription polymerase chain reaction, and protein expression was evaluated using Western blot. To evaluate the relationship among mitogen-activated protein kinases (MAPKs), activator protein 1 (AP-1), and FLG, we also treated cells with inhibitors for MAPKs JNK, p38, and ERK1/2. Results: FLG and FLG-2 mRNA expression in NHEKs significantly increased after treatment with $10{\mu}g/ml$ adiponectin. Adiponectin also restored FLG and FLG-2 mRNA expression that was otherwise inhibited by treatment with IL-4 and IL-13. Adiponectin induced FLG expression via AP-1 and MAPK signaling. Conclusion: Adiponectin positively regulated the expression of FLG and could be useful as a therapeutic agent to control diseases related to disrupted skin barrier function.

• Journal of Cancer Prevention
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• v.21 no.3
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• pp.144-151
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• 2016

Background: Immunoregulatory elements have emerged as useful immunotherapeutic agents against cancer. In traditional medicine, Mori folium, the leaf of Morus alba L. (Moraceae), has been used for various medicinal purposes; however, the immunomodulatory effects have not been fully identified. We evaluated the immunoenhancing potential of water extract of Mori folium (WEMF) in murine RAW264.7 macrophages. Methods: RAW264.7 cells were treated with WEMF for 24 hours and cell viability was detected by an MTT method. Nitric oxide (NO) levels in the culture supernatants were assayed using Griess reagent. The productions of prostaglandin $E_2$ ($PGE_2$) and immune-related cytokines was measured using ELISA detection kits. The mRNA and protein expression levels of Inducible NO synthase, COX-2, and cytokines were assayed by reverse transcription-PCR and Western blotting, respectively. The effect of WEMF on phagocytic activity was measured using a Phagocytosis Assay Kit. Results: WEMF significantly stimulated the production of NO and $PGE_2$ as immune response parameters at noncytotoxic concentrations, which was associated with the increased expression of inducible NO synthase and COX-2. The release and expression of cytokines, such as $TNF-{\alpha}$, interleukin $(IL)-1{\beta}$, IL-6, and IL-10, were also significantly increased in response to treatment with WEMF. Moreover, WEMF promoted the macrophagic differentiation of RAW264.7 cells and the resulting phagocytosis activity. Conclusions: WEMF has the potential to modulate the immune function by regulating immunological parameters. Further studies are needed to identify the active compounds and to support the use of WEMF as an immune stimulant.