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Effects of Large Display Curvature on Postural Control During Car Racing Computer Game Play (자동차 경주 컴퓨터 게임 시 대형 디스플레이 곡률이 자세 제어에 미치는 영향)

  • Yi, Jihhyeon;Park, Sungryul;Choi, Donghee;Kyung, Gyouhyung
    • Journal of the HCI Society of Korea
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    • v.10 no.2
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    • pp.13-19
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    • 2015
  • Display technology has recently made enormous progress. In particular, display companies are competing each other to develop flexible display. Curved display, as a precursor of flexible display, are now used for smart phones and TVs. Curved monitors have been just introduced in the market, and are used for office work or entertainment. The aim of the current study was to investigate whether the curvature of a 42" multi-monitor affects postural control when it is used for entertainment purpose. The current study used two curvature levels (flat and 600mm). Ten college students [mean(SD) age = 20.9 (1.5)] with at least 20/25 visual acuity, and without color blindness and musculoskeletal disorders participated in this study. In a typical VDT environment, each participant played a car racing video game using a steering wheel and pedals for 30 minutes at each curvature level. During the video game, a pressure mat on the seat pan measured the participant's COP (Center of Pressure), and from which four measures (Mean Velocity, Median Power Frequency, Root-Mean-Square Distance, and 95% Confidence Ellipse Area) were derived. A larger AP (Anterior-Posterior) RMS distance was observed in the flat condition, indicating more forward-backward upper body movements. It can be partly due to more variability in visual distance across display, and hence longer ocular accommodation time in the case of the flat display. In addition, a different level of presence or attention between two curvature conditions can lead to such a difference. Any potential effect of such a behavioral change by display curvature on musculoskeletal disorders should be further investigated.

Delphinidin Chloride Effects on the Expression of TNF-$\alpha$ Induced Cell Adhesion Molecules (TNF-$\alpha$에 의해 유도된 세포부착분자의 발현에 대한 Delphinidin chloride의 억제 효과)

  • Koh, Eun-Gyeong;Chae, Soo-Chul;Seo, Eun-Sun;Na, Myung-Suk;Lee, Jong-Bin
    • Korean Journal of Environmental Biology
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    • v.27 no.1
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    • pp.88-94
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    • 2009
  • The process of atherosclerosis begins through secretion of inflammatory cytokine or adhesion of leukocyte from damage in blood vessels and transmigration. This study was conducted to investigate the effects of delphinidin chloride (DC) in the initial process of atherosclerosis on the expression of ICAM-1 (Intracellular Adhesion Molecule-1) and VCAM-1 (Vascular Adhesion Molecule-1) related to adhesion of leukocyte at the HUVEC (human umbilical vein endothelial cell line. As a result, cell growth inhibition rate at 50 ${\mu}M$ was respectively 4, 3 and 5% without cell toxicity. As a result of morphological observation monocyte-endothelial cell adhesion assay and optical microscope carried out to measure attachment of mononuclear cells to endothelial cells induced by Tumor necrosis factor-alpha (TNF-$\alpha$) at concentrations without cell toxicity, DC concentration-dependently suppressed attachment. When effects on the expression of VCAM-1 and ICAM-1, cell adhesion molecules induced from endothelial cells by TNF-$\alpha$, were comparatively analyzed using western blot analysis and RT-PCR methods, protein of VCAM-1 and ICAM-1 and expression at the level of mRNA were concentration-dependently reduced. Taken together, the results of this studies provide evidence that DC possess an anti-metastatic activity.

Granulomatous Meningoencephalitis in an Old Dog ; magnetic resonance imaging and immunohistopathologic findings (노령견에서 병발한 육아종성 뇌수막염 증례 보고: 자기 공명 영상 및 면역조직병리학 소견)

  • Jung, Dong-In;Yoo, Jong-Hyun;Kang, Byeong-Teck;Park, Chul;Gu, Su-Hyun;Kim, Ju-Won;Jeon, Hyo-Won;Lee, So-Young;Woo, Eung-Je;Sur, Jung-Hyang;Park, Hee-Myung
    • Journal of Veterinary Clinics
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    • v.24 no.3
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    • pp.406-409
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    • 2007
  • A 12-year-old female mixed Chihuahua dog was referred because of acute blindness and progressive tetraparesis. Mutifocal lesions in the cerebrum were noted on brain magnetic resonance images and cerebrospinal fluid analysis showed monocytic pleocytosis. Based on these results, granulomatous meningoencephalitis (GME) was strongly suspected. Cerebral lesions were definitely diagnosed as GME based on histopathological findings and positive results of immunohistological stains of brain with T-cell marker (CD3). This report describes the clinical findings, diagnostic imaging characteristics, and immunohistopathologic features of GME in an old dog. In addition, this case demonstrates that clinical signs of GME were mediated by perivascular infiltration of T lymphocytes and identification of causes in T cell-mediated inflammation should be further studied.

Change in Axial Rotation of Toric Soft Contact Lens according to Tear Volume (눈물양에 따른 토릭 소프트콘택트렌즈의 축 회전양 변화)

  • Seo, Woo Hyun;Kim, So Ra;Park, Mijung
    • Journal of Korean Ophthalmic Optics Society
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    • v.20 no.4
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    • pp.445-454
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    • 2015
  • Purpose: The present study was aimed to investigate the effect of tear volume on a change of axial rotation according to wearing time of toric soft contact lens and gaze directions. Method: Toric soft contact lenses with double thin zone design applied on 62 eyes. Then, changes in non invasive tear film break-up time and the rotational direction/amount of lens when changing gaze direction were respectively measured after 15 minutes and 6 hours of lens wear. Results: Lens rotation to temporal direction was more found when changing gaze direction after lens wear. However, its rotation was varied according to wearing time and the subjects' tear volume. Furthermore, the frequency of lens rotation to temporal direction was higher in dry eyes compared with normal eyes at nearly all gaze directions after 15 minutes and 6 hour of lens wear. The rotational amount of lens was generally greater in dry eyes after 15 minutes of lens wear. However, its difference between normal eyes and dry eyes was not great after 6 hours of lens wear. Conclusion: The present study revealed that axial rotation of toric soft contact lens was varied according to the wearer's tear volume and lens rotational patterns at the initial, and extending periods of lens wear were different. The change in rotational pattern of toric soft contact lens from these results means the possibility of visual change after extending lens wear, and the identification of its correlation with tear volume suggests the necessity of considering factors for choosing appropriate toric soft contact lens.

A Study on the Accommodative Astigmatism of Near Vision (근거리 주시 시 조절성 난시에 대한 연구)

  • Lee, Hark-Jun
    • Journal of Korean Ophthalmic Optics Society
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    • v.16 no.3
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    • pp.327-331
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    • 2011
  • Purpose: The purpose of this study was an accurate grasp of the astigmatic change due to eyes accommodation on near vision and suggested problems occurring accommodative astigmatism using near glasses. Methods: 154 subjects(308eyes) from 20 to 40 years selected for this study who had many opportunity of near vision. First, far vision corrective refraction measured using the phoropter, and then both eyes opened simultaneously for maintaining the function of binocular put away dot chart 40 cm. One eye was fogging and the other eye measured near vision astigmatism axis and degrees astigmatism using cross cylinder, and then compared with far astigmatism. Results: Increased degree of astigmatism persons on near vision more than decreased or did not changed degree of astigmatism persons, which could affect visual acuity more than 0.75 diopters in 30 eyes with an increase of 9.7% of total subjects. Direct astigmatism and oblique astigmatism were increased on near vision. Astigmatic axes were rotated base in direction on both eyes and 66.9% of subjects were more than ${\pm}$5$^{\circ}$ rotation. Due to the rotation axis of astigmatism, residual astigmatism is expected to occur and expect to adversely affect the eyes. Conclusions: Long-term using the glasses without correction of increased astigmatic and rotated axis on near vision should occur new residual astigmatism and increase the asthenopia also. Considered to be taken astigmatic change on near vision during near refraction examination.

Effects of Wearing Corrective Glasses for Presbyopia on Age-related Hyperopic Shifts and Reading Addition (노안보정용 안경 착용이 연령관련 원시화와 근용가입도 변화에 미치는 영향)

  • Lee, Koon-Ja;Kim, Jin-Han;Mun, Mi-Young;Leem, Hyun-Sung
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.3
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    • pp.65-73
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    • 2009
  • Purpose: This study was conducted to investigate the changes in distance refractive power and reading addition that occur after wearing corrective glasses for prebyopia. Methods: The subjects aged 42 to 75 years who had no ophthalmologic diseases and did not undergo cataract or retina surgery, had a corrected visual acuity of 20/20 and did not have a previous history of wearing corrective glasses for presbyopia. These subjects were divided into 3 groups: the control, reading spectacles and multifocals wearing group and they were measured for distance refractive power and reading addition at their visit. The maximum follow-up period was 73 months. Results: As for distance refractive power, the power tends to shift to hyperopia depending on age (r=0.486, p<.001) and 50.0% of the subjects increased plus power during this study period. Plus power Increments per year in distance refractive power in the reading spectacle wearing group were significantly different with control and multifocals wearing group (p<.05). On the other hand, the multifocals wearing group's increments were not different with control. Increments in reading addition were also increased in the reading spectacles group than in the control and multifocals wearing groups (p<.05). Conclusions: The age related hyperopic shift could be occurred in the elderly people, routine refraction is mandatory. And reading spectacles could induce an age related hyperopic shift and the additional need for reading addition that the prescription of multifocals may reduce changes in distance refractive power and reading addition.

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A Clinical Study on Relation among Accommodative Amplitude, Response, and Facility in young adults (청.장년층에서 조절력 및 조절반응과 조절용이의 상관관계에 관한 임상적 연구)

  • Shim, Hyun-Seog;Joo, Seok-Hee;Leem, Hyun Sung
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.1
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    • pp.115-119
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    • 2009
  • Purpose: This study has been conducted to know the relation among accommodative amplitude, response, and facility. Methods: 61 subjects were students without any ocular diseases and presbyopia in a university, Korea. After far distance visual acuity was fully corrected, the amplitude was measured through Push-Up test, the response was measured through Jackson crossed cylinder ${\pm}$0.25D and the facility was measured through +2.00/ -2.00D flipper. Results: The relation among accommodative facility, response and amplitude had not indicate significant level in monocular and binocular. In binocular, 12 eyes (19.6%) had a difference in amplitude, 9 eyes (14.7%) had a difference in response, 2 eyes (3.2%) had a difference in facility from norm which would be expected from their age. 4 eyes (6.5%) had difference in both amplitude and response. 2 eye (3.2%) had difference in both amplitude and facility. In all three of the amplitude, response, facility had not difference. Conclusions: The evaluation of accommodative functions and a patients accommodative dysfunction is examined all facets of amplitude, response, and facility.

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Examination of Refractive Correction and Accommodative Ability on Myopic Elementary School Children Wearing Glasses in Jinju City (진주지역 근시 안경착용 초등학생들의 굴절교정상태와 조절기능의 검사)

  • Nam, Woon-Go;Cho, Hyun Gug;Son, Jeong-Sik;Kwak, Ho-Weon;Moon, Byeong-Yeon
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.1
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    • pp.109-114
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    • 2009
  • Purpose: This study was designed to investigate the condition of refractive correction on wearing glasses currently of elementary school children and their accommodative ability in Jinju city. Methods: Objective refraction, subjective refraction, amplitude of accommodation, negative and positive accommodation, accommodative facility, and dynamic retinoscopy were examined on 60 elemenary school children who aged 8~12 wearing myopiacorrected glasses. Results: The condition of refractive corrections was distributed that a case of full correction was 11.7%, a case of low correction with more than 0.8 visual acuity (VA) was 10%, and a case of low correction with less than 0.8 VA was 78.3% in wearing glasses currently. In results from examination of accommodative ability, the number of children having accommodative anomaly is 8 persons (13.3%), they were divided into accommodation insufficiency (4 persons), accommodative facility insufficiency (2 persons), accommodation excess (1 person), and accommodation insufficiency related to ocular function (1 person). Conclusions: It is demanded a periodic inspection of refractive correction to growing children, and the refractive correction after due consideration to accommodative ability is really needed.

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The Relationship between Habitual Patient-Reported Symptoms and Signs in the Soft Contact Lens Wearers (소프트 콘택트렌즈 착용자에서 평상시 나타난 증상에 관한 연구)

  • Lee, Koon-Ja;Buyn, Jang-Won;Mun, Mi-Young;Leem, Hyun-Sung
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.3
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    • pp.19-28
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    • 2008
  • Purpose: To understand symptoms and signs in soft contact lens wearers the authors evaluate the attribution of the tear test to the contact lens related symptoms and signs. Methods: Sixty-two healthy soft contact lens wearers (23.95${\pm}$4.38 years old, 18.60${\pm}$16.92 months of prior lens wear) were participated in this study. 3 kinds of tear test and McMonnies' questionnaire test were performed for the soft contact lens wearers and subjective symptoms and objective signs were graded using CCLRU scales during the study period. Results: In this surveys, we found ocular dryness, redness and tiredness are the most common frequent and severe symptoms in soft contact lens wearers. Frequency of the ocular dryness, redness and tiredness are associated with grittiness, burning sensation and foreign body sensation respectively, and severity of the photophobia, foreign body sensation are associated with unstable vision and grittiness and which are associated with score of McMonnies' Questionnaire. Conjunctival redness and limbal redness are major signs but those are not need to be clinical care and rarely occurred corneal and conjunctival staining which are associated with tear break-up-time statistically. Conclusions: Dryness, redness and tiredness are primary common symptoms in Korean soft contact lens wearers. The frequency of those symptoms are increased with the period of soft contact lens wear and those are associated with other symptoms but have no relationship with signs.

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Psychosocial Factors and Its Related Factors Among the Elderly People in a City (도시지역 노인들의 사회심리적 요인과 그의 관련요인)

  • Song, Young-Soo;Kwon, In-Sun;Cho, Young-Chae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.8
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    • pp.3521-3531
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    • 2012
  • This study was performed to determine the relationships among self-esteem, state anxiety, interpersonal behavior trait and locus of control, and to reveal its related factors. The interviews were performed, during the period from April 1st, to June 30th, 2011, to 396 elderlies in Daejeon city. As a results, the self-esteem was negatively correlated with state anxiety and interpersonal behavior trait, while it was positively correlated with locus of control. While state anxiety was positively correlated with interpersonal behavior trait, it was negatively correlated with locus of control, and interpersonal behavior trait was positively correlated with locus of control. Multiple stepwise analysis revealed that the factors of influence on self-esteem included IADL, spouse, mastication of food and amnesia. The factors of influence on State anxiety included mastication of food, IADL, spouse, subjective health status, disability of body, subjective sleep evaluation and educational level. The factors of influence on Interpersonal dependent behavior trait included spouse, IADL, monthly income and subjective health status. The factors of influence on locus of control included spouse and visual acuity. Above results suggested that the self-esteem, state anxiety, interpersonal behavior trait and locus of control of subjects were significantly related with the sociodemographic characteristics, health related factors and health status.