• BMB Reports
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• v.44 no.4
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• pp.217-231
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• 2011

T cell exhaustion develops under conditions of antigen-persistence caused by infection with various chronic pathogens, such as human immunodeficiency virus (HIV) and myco-bacterium tuberculosis (TB), or by the development of cancer. T cell exhaustion is characterized by stepwise and progressive loss of T cell function, which is probably the main reason for the failed immunological control of chronic pathogens and cancers. Recent observations have detailed some of the intrinsic and extrinsic factors that influence the severity of T cell exhaustion. Duration and magnitude of antigenic activation of T cells might be associated with up-regulation of inhibitory receptors, which is a major intrinsic factor of T cell exhaustion. Extrinsic factors might include the production of suppressive cytokines, T cell priming by either non-professional antigenpresenting cells (APCs) or tolerogenic dendritic cells (DCs), and alteration of regulatory T (Treg) cells. Further investigation of the cellular and molecular processes behind the development of T cell exhaustion can reveal therapeutic targets and strategies for the treatment of chronic infections and cancers. Here, we report the properties and the mechanisms of T cell exhaustion in a chronic environment.

• Journal of the Korean Society of Physical Medicine
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• v.13 no.3
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• pp.133-139
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• 2018

PURPOSE: Despite the abundant literature available regarding the activity of intrinsic muscles, few studies have investigated the muscle activity of extrinsic muscles. Therefore, the present study compared the muscle activity of the peroneus longus, tibialis anterior, and abductor hallucis during short foot exercise in subjects with and without flat feet. METHODS: Twelve subjects with and without pes planus participated in this study. During the short foot exercises, muscular activity of the tibialis anterior, fibularis longus, and abductor hallucis longus were measured in both groups. To identify the effects of short foot exercises, navicular drop height was also investigated in pre and post short foot exercises. RESULTS: In a symptomatic group, the navicular drop height was significantly reduced at post measurement compared with pre-measurement. During the short foot exercise, the pes planus group showed significantly lower activities of the fibularis longus than the control group (p<.05). CONCLUSION: Similar to previous studies and clinical literature, short foot exercise was effective for alleviating navicular drop for a population with pes planus. In addition, subjects with pes planus showed decreased muscular activities of the fibularis longus, which suggests that considering extrinsic muscles such as fibularis longus is also important for rehabilitation of pes planus patients.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.6
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• pp.2129-2144
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• 2015

Programmed cell death (PCD) or apoptosis is a mechanism which is crucial for all multicellular organisms to control cell proliferation and maintain tissue homeostasis as well as eliminate harmful or unnecessary cells from an organism. Defects in the physiological mechanisms of apoptosis may contribute to different human diseases like cancer. Identification of the mechanisms of apoptosis and its effector proteins as well as the genes responsible for apoptosis has provided a new opportunity to discover and develop novel agents that can increase the sensitivity of cancer cells to undergo apoptosis or reset their apoptotic threshold. These novel targeted therapies include those targeting anti-apoptotic Bcl-2 family members, p53, the extrinsic pathway, FLICE-inhibitory protein (c-FLIP), inhibitor of apoptosis (IAP) proteins, and the caspases. In recent years a number of these novel agents have been assessed in preclinical and clinical trials. In this review, we introduce some of the key regulatory molecules that control the apoptotic pathways, extrinsic and intrinsic death receptors, discuss how defects in apoptotic pathways contribute to cancer, and list several agents being developed to target apoptosis.

• Journal of the Korean Operations Research and Management Science Society
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• v.33 no.1
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• pp.131-148
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• 2008

Today, it is not difficult to use information technology (IT), especially, Internet based ones. Many people can not only access IT without learning how to use it but also find and develop new techniques and usages which couldn't be expected by system engineers or designers. This is owing to social interactions among users as well as advancement of IT. Theoretically, such social interactions in using IT can be well explained by adaptive structuration theory (AST) which has been considered as one of trying to capture the change of using IT due to social interactions between users and system. This study is to analyze the relationship between social interactions and motivation in using IT which can determine attitude and intention of using IT. For this purpose we provide a research model, in which two AST related variables, faithfulness of appropriation and consensus on appropriation, are independent variables and three beliefs for using IT, usefulness, ease of use and playfulness, are dependent ones. Additionally, for reflection of changing uses, usefulness is formed as second order factor by two first order factors-usefulness of self-expression and communication. An empirical test of our model for blog users which is analyzed by Partial Least Square method shows supporting most of hypotheses except one, consensus-ease of use.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05b
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• pp.61-66
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• 2001

NiO-doped $WO_3$ thick films were prepared by a screen printing technique. The electrical property and microstructure of the films were investigated with the partial pressure of oxygen and the amount of NiO. The grain size of NiO-doped $WO_3$ was smaller than that of undoped $WO_3$, but the grain size of 0.1, 1, 10 mol% NiO-doped $WO_3$ were nearly the same. The electrical conductance of the $WO_3$ thick films decreased with the oxygen partial pressure, and increased with the amount of NiO to the limit of solid solution. The variation of the electrical conductance with temperature is not so large in the extrinsic region, but it changed rapidly in the intrinsic region. The conductance decreased with adsorption of oxygen in the intermediate range between the extrinsic and intrinsic region.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.4
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• pp.483-490
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• 2009

In this paper, a novel low-damage silicon nitride passivation for 100nm InAlAs/InGaAs MHEMTs has been developed using remote ICPCVD. The silicon nitride deposited by ICPCVD showed higher quality, higher density, and lower hydrogen concentration than those of silicon nitride deposited by PECVD. In particular, we successfully minimized the plasma damage by separating the silicon nitride deposition region remotely from ICP generation region, typically with distance of 34cm. The silicon nitride passivation with remote ICPCVD has been successfully demonstrated on GaAs MHEMTs with minimized damage. The passivated devices showed considerable improvement in DC characteristics and also exhibited excellent RF characteristics($f_T$of 200GHz).The devices with remote ICPCVD passivation of 50nm silicon nitride exhibited 22% improvement(535mS/mm to 654mS/mm) of a maximum extrinsic transconductance($g_{m.max}$) and 20% improvement(551mA/mm to 662mA/mm) of a maximum saturation drain current ($I_{DS.max}$) compared to those of unpassivated ones, respectively. The results achieved in this work demonstrate that remote ICPCVD is a suitable candidate for the next-generation MHEMT passivation technique.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.6
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• pp.279-283
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• 2003

In this study, ZnTe : S single crystal thin films substituted by sulfur were grown on GaAs (100) substrates by hot-wall epitaxy. The photoluminescence (PL) characteristics of ZnTe : S single crystal thin films was measured to investigate the effects due to sulfur atoms in the ZnTe layer. The Peak of 2.339 eV identified as the isoelectronic center was observed in low temperature PL spectrum, but PL spectra which the origin had not been well-explained were not observed. Temperature dependence of PL intensities of the light hole free exciton was explained by extrinsic self-trapping. Besides it is reported that the emission lines near absorption edge at room temperature were observed.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.6
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• pp.601-607
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• 2012

The recognition of elevator door is needed for mobile service robots to moving between floors in the building. This paper proposed the sensor fusion approach using LRF (Laser Range Finder) and camera to solve the problem. Using the laser scans by the LRF, we extract line segments and detect candidates as the elevator door. Using the image by the camera, the door candidates are verified and selected as real door of the elevator. The outliers are filtered through the verification process. Then, the door state detection is performed by depth analysis within the door. The proposed method uses extrinsic calibration to fuse the LRF and the camera. It gives better results of elevator door recognition compared to the method using LRF only.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.6
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• pp.537-542
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• 2015

The measurement of 3D shape is important in inspecting the quality of product. In this paper, we present a 3D shape measurement system of fastener using a camera and a slit laser. Calibration structure with slits is used in the extrinsic calibration of the camera and laser. The pose of the camera and laser is computed under the same world coordinate system in the calibration structure. Reflection of laser light on the metal surface causes many difficulties in the robust detection of them on image. We overcome this difficulty by using color and dynamic programming. Motor stage is used to rotate the fastener to recover the whole 3D shape of the surface of it.

• The Research Journal of the Costume Culture
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• v.23 no.6
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• pp.1021-1037
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• 2015

This study analyzed the impact of sense of self-efficacy on job satisfaction and organizational commitment among technical designers in order to acquire information needed for human resources management in the field of technical design. The study was implemented through a normative-descriptive survey method using a questionnaire. The sample consisted of 217 technical designers working at vendors and agents located in Seoul. The results revealed that there were significant differences in the sense of self-efficacy levels among technical designers according to age and work experience. Personal self-efficacy had a positive influence on both intrinsic and extrinsic job satisfaction, but also on affective, continuance, and normative organizational commitment. In addition, personal self-efficacy had a greater influence on extrinsic job satisfaction than social self-efficacy. Both personal and social self-efficacy influenced continuance commitment while there was no relationship between social self-efficacy and affective organizational commitment. However, a clear relationship was found between both social and personal self-efficacy and normative organizational commitment. Nevertheless, social self-efficacy had a greater influence on normative organizational commitment than personal self-efficacy. This fact demonstrates the need to exert more effort to promote the sense of personal self-efficacy of technical designers. These results could be used to provide appropriate proposals for human resources management in the field of technical design.