• Nutrition Research and Practice
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• v.16 no.6
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• pp.729-744
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• 2022

BACKGROUND/OBJECTIVES: 4-Hydroxy-2-nonenal (HNE) is a biomarker for oxidative stress to induce inflammation. Methionine is an essential sulfur-containing amino acid with antioxidative activity. On the other hand, the evidence on whether and how methionine can depress HNE-derived inflammation is lacking. In particular, the link between the regulation of the nuclear factor-κB (NF-κB) signaling pathway and methionine intake is unclear. This study examined the link between depression from HNE accumulation and the anti-inflammatory function of ⳑ-methionine in rats. MATERIALS/METHODS: Male Wistar rats (3-week-old, weighing 70-80 g) were administered different levels of ⳑ-methionine orally at 215.0, 268.8, 322.5, and 430.0 mg/kg body weight for two weeks. The control group was fed commercial pellets. The hepatic HNE contents and the protein expression and mRNA levels of the inflammatory mediators were measured. The interleukin-10 (IL-10) and glutathione S-transferase (GST) levels were also estimated. RESULTS: Compared to the control group, hepatic HNE levels were reduced significantly in all groups fed ⳑ-methionine, which were attributed to the stimulation of GST by ⳑ-methionine. With decreasing HNE levels, ⳑ-methionine inhibited the activation of NF-κB by up-regulating inhibitory κBα and depressing phosphoinositide 3 kinase/protein kinase B. The mRNA levels of the inflammatory mediators (cyclooxygenase-2, interleukin-1β, interleukin-6, inducible nitric oxide synthase, tumor necrotic factor alpha) were decreased significantly by ⳑ-methionine. In contrast, the protein expression of these inflammatory mediators was effectively down regulated by ⳑ-methionine. The anti-inflammatory action of ⳑ-methionine was also reflected by the up-regulation of IL-10. CONCLUSIONS: This study revealed a link between the inhibition of HNE accumulation and the depression of inflammation in growing rats, which was attributed to ⳑ-methionine availability. The anti-inflammatory mechanism exerted by ⳑ-methionine was to inhibit NF-κB activation and to up-regulate GST.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.10
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• pp.2171-2180
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• 1997

In this paper, we proposed a MAC protocol called P/S-DCA that using dynamci channel allocation scheme for supports the multimedia traffic in wireless ATM, and analysis theoretically the throughput and delay of up/down link according to varying the down traffic load. To evaluate and the dynamic channel allocation scheme, simulations are executed with varying down traffic load. The results are proved that system capacity is improved better than PRMA and C-PRAM. The system capacity, denoting by $M_{0.01}$, is defined as the maximum number of conversations which can be supported under constraint of packet dropping probability no more than 1%. It is shown that the values of $M_{0.01}$ for ${\lambda}_{d}=0.5,\;{\lambda}_{d}=0.2\;{\lambda}_{d}=0.1\;{\lambda}_{d}=0.001$ are about 43, 69, 77 and 83, respectively. This indicates that P/S-DCA protocol achieves a significant improvement in system capacity relative to PRMA and C-PRMA protocol.

• Molecules and Cells
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• v.44 no.3
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• pp.146-159
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• 2021

DNA methylation, and consequent down-regulation, of tumour suppressor genes occurs in response to epigenetic stimuli during cancer development. Similarly, human oncoviruses, including human papillomavirus (HPV), up-regulate and augment DNA methyltransferase (DNMT) and histone deacetylase (HDAC) activities, thereby decreasing tumour suppressor genes (TSGs) expression. Ubiquitin-like containing PHD and RING finger domain 1 (UHRF1), an epigenetic regulator of DNA methylation, is overexpressed in HPV-induced cervical cancers. Here, we investigated the role of UHRF1 in cervical cancer by knocking down its expression in HeLa cells using lentiviral-encoded short hairpin (sh)RNA and performing cDNA microarrays. We detected significantly elevated expression of thioredoxin-interacting protein (TXNIP), a known TSG, in UHRF1-knockdown cells, and this gene is hypermethylated in cervical cancer tissue and cell lines, as indicated by whole-genome methylation analysis. Up-regulation of UHRF1 and decreased TXNIP were further detected in cervical cancer by western blot and immunohistochemistry and confirmed by Oncomine database analysis. Using chromatin immunoprecipitation, we identified the inverted CCAAT domain-containing UHRF1-binding site in the TXNIP promoter and demonstrated UHRF1 knockdown decreases UHRF1 promoter binding and enhances TXNIP expression through demethylation of this region. TXNIP promoter CpG methylation was further confirmed in cervical cancer tissue by pyrosequencing and methylation-specific polymerase chain reaction. Critically, down-regulation of UHRF1 by siRNA or UHRF1 antagonist (thymoquinone) induces cell cycle arrest and apoptosis, and ubiquitin-specific protease 7 (USP7), which stabilises and promotes UHRF1 function, is increased by HPV viral protein E6/E7 overexpression. These results indicate HPV might induce carcinogenesis through UHRF1-mediated TXNIP promoter methylation, thus suggesting a possible link between CpG methylation and cervical cancer.

• Tribology and Lubricants
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• v.36 no.1
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• pp.27-33
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• 2020

Self-equalizing tilting pad thrust bearings are usually employed in turbomachines to achieve high stability and reliability. A tilting pad bearing can incorporate self-equalizing links to handle the misalignment between the bearing and the thrust collar. In this popular design method, the pads sit on the upper-level plates and the lower-level plates stay on the retainer base. With misalignment, the pads that are heavily loaded are pushed down. Consequently, the link pushes up the pads on the opposite side, keeping the bearing surface parallel to the thrust collar surface. The self-equalizing link is used to handle the misalignment from the thermal and mechanical effects. In this study, the experimental investigation deals with the performance of self-equalizing tilting pad thrust bearings. The test rig for evaluating the performance of bearing is developed which can control the misalignment angle. Simultaneous measurements are taken for the force acting on each pad. Pad metal temperature and oil film thickness are functions of the shaft speed, bearing load, misalignment angle, and design of leveling plates. The effect of misalignment on bearing performance is discussed. The results demonstrate that the load on each pad depends on the test conditions(especially misalignment angle), and the load influences the performance of bearings.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.2
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• pp.83-90
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• 2000

In this paper, a stacked circular-disk microstrip 1${\times}$4 array antenna was designed and manufactured and tested to apply in next generation mobile communication, on IMT-2000 system(up-link: 1.885 GHz∼2.025 GHz, down-link: 2.11 GHz∼2.2 GHz) base station which has dual frequency, broadband and high-gain characteristics. The experimental results are as follows : resonant frequency of 1.885 GHz and 2.178 GHz VSWR (1.064 , 1.432), return loss (-30.19 dB , -24.99 dB), band width (VSWR<2) are 402 MHz, -3dB beam width at radiation pattern are ${\alpha}$E-16.8$^{\circ}$, ${\alpha}$H-69$^{\circ}$(1.885 GHz) and ${\alpha}$E-l5.2$^{\circ}$, ${\alpha}$H-51.5$^{\circ}$(2.178 GHz), gain(13.7 dBi∼15.21 dBi).

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.6
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• pp.1-12
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• 1999

This paper illustrates and analyzes system structure, link budget and cell coverage to accommodate Korea environment about LMDS systems that are expected to play an important role as the future wireless infrastructure of the information superhighway. In the mean time, many parameters used for the analysis apply to the allocated frequency bandwidth (Up-stream : 24.25GHz-24.75GHz, Down-stream : 25.5GHz-27.5GHz) of Ministry of Information and Communication. The modem and channel coding must be developed to accommodate specifications of DAVIC protocol. The materials about atmospheric phenomena refer to apply specifications of ITU-R. This paper will be need to disign the network structure and system configuration of LMDS system.

• Journal of Digital Contents Society
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• v.16 no.4
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• pp.615-622
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• 2015

Recently virtual advertising is located in an important area of interest in the TV market by convenience of application and reduction of cost. The methods of inserting a virtual advertising in broadcasting are Up-link that method insert the image through the production equipment of the broadcasting station and dispatch equipment and technical personnel in the shooting and Down-streaming that method insert a virtual image automatically in relay video using image processing technology. In recent years, the image processing technology is an important research area in the virtual advertising area for automatically insertion of advertising images. In this paper, we propose the method to extract less-informative region in sports video using image processing. The proposed method extracts less-Informative region through rectangle detection of Hough transform and analysis of color histogram distribution.

• The Korean Journal of Archival Studies
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• no.11
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• pp.123-143
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• 2005

1. Introduction : From the Memorial to the Records, From the Records to the Archives 2. Archivists and Historians : the Records Keeping, Appraisal and Selection 3. Records and Historical Materials in the Historical Narrative 4. the Relation of the Facts and Theory in the History 5. Conclusion In this essay I considered the relations of records and history, namely the process on the selection and choice from the records to the archives and the historical materials and in the process the role on the archivists and historians and difference and the relation of the facts and theory in the history. Archival science posits that an archives is the whole of the documents made or received in the course of purposeful activity, and of the relationships among those documents. Archival theory posits that it is the primary function of the archivists to maintain unbroken, continuing custody of societal archives, and to protect their integrity by keeping them physically and intellectually uncorrupted. The ultimate purpose of archival endeavors is to hand down to the next generations a reliable, trustworthy, and complete testimony of societal actions so that they can constitute sources of, and foundations for, future decision making. However, historical science searches for the truth in the historical facts, explains the cause and origin of the matters and reflects on th knowledge about the why and how the events happened. And history is firmly rooted on the philosophy. The goal of historian is analysing the nature of meaning of past in the society and tracing up the change and process of the transition. Archival science means historical source studies and other related disciplines. On the other hand archival management is the principle of respect for original order and the importance of original forms and conditions. Thus the relations between archival science and archives management are not one-sided but mutual. Archival science and historical studies, archivists and historians need to link more closely in order to hand down the contemporary memorial, the common memorial of mankind to the future.

• Korean Journal of Computational Design and Engineering
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• v.20 no.3
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• pp.312-319
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• 2015

The grinding and furbishing process as the finishing process for molds include the works such as the grinding, buffing, lapping and polishing among others. A finishing tool unit is applied to this finishing process for the burr, lapping, polishing and others of molds. A finishing tool unit can carry out the flexible machining, depending on the machining allowance for objects to be cut on the basis of the instrumental driving mechanism which enables the up, down, left and right floating, which is applied in link with the dedicated cutters and robot machining systems. This study selected the shape to increase the rotatory force of an impeller when air is discharged during the driving of a finishing tool unit, and reflected it to the impeller designing. In addition, the study analyzed each flow velocity and pressure distribution per air pressurization value and finally analyzed the rotating torque to suggest the optimal conditions in designing impellers.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.2
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• pp.305-310
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• 2012

Planetary gear box is a power transmitter having very high gear ratio in compact volume. The planetary step-down gear box converts high speed and low torque into low speed and high torque, which is widely used in constructional and industrial machinery field. And, the planetary step-up gear box does vice versa working, which is used as main gear box of large sized wind mill system. The large sized planetary gear box must be performed the normal-opposite rotation test as a its durability test for achieving the reliability. The large sized planetary gear box is composed by triple gear trains of sun gear, carrier, and ring gear. If input power is supplied into one of them and the other is fixed, and then another becomes the output part. In this paper, we designed a new test equipment which can do rapid normal and opposite rotational change with only small displacement by supplying test power using the above rotation (driving) characteristics and hydraulic cylinder and link, and also compared and analyzed with existing method through various experiments.