• Title/Summary/Keyword: Functional lens

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Contrast Sensitivity and Glare with Spherical and Toric Soft Contact Lenses in Low-astigmatic Eyes (구면과 토릭 소프트 렌즈로 교정한 약도 난시안의 대비감도와 눈부심)

  • Lee, Min-Ah;Kim, Hyun Jung;Kim, Jai-Min
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.1
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    • pp.39-45
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    • 2009
  • Purpose: The purpose of this study is to compare the visual performance by contrast sensitivity (CS) and disability glare (DG) in low astigmatic eyes corrected with toric soft lenses and other optical corrections. Methods: Twenty university students with myopia (-1.00 to -6.50D Sph. with astigmatism up to 1.50 cyl) were enrolled and corrected by five different methods: 1) soft toric lenses; 2) spherical soft contact lenses; 3) RGP lenses; 4) best spectacle corrected visual acuity; 5) spherical equivalent spectacles. All subjects had corrected vision acuity of 20/20 or better. Contrast sensitivity and disability glare were measured using the OPTEC 6500 contrast sensitivity view-in tester included the EyeView Functional Vision Analysis software at photopic or mesopic conditions with glare. Results: At photopic condition, best corrected spectacle wearers had the highest monocular contrast sensitivity at all spatial frequency followed by soft toric lenses, RGP lenses, spherical equivalent spectacles, and spherical soft contact lenses. However, all of them were in normal contrast sensitivity value at photopic condition. At mesopic condition with glare, toric soft lenses were the highest and followed by RGP lenses, spherical equivalent spectacles, best spectacle corrected visual acuity and spherical soft contact lenses. It was observed that spherical soft contact lens wearers demonstrated lower range than normal contrast sensitivity value at mesopic condition with glare. Conclusion: Toric soft lenses gave better visual performance than spherical soft lenses in low astigmatic eyes. Subjects requiring the use of contact lenses under mesophic conditions could benefit from toric soft lenses.

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Three Dimensional Reconstruction of Cellular Structure in Drosophila Retina Using High Voltage Electron Microscopy (초고압전자현미경을 이용한 초파리 망막 세포의 3차원 구조)

  • Mun, Ji-Young;Lee, Kyung-Eun;Han, Sung-Sik
    • Applied Microscopy
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    • v.39 no.2
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    • pp.185-189
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    • 2009
  • Studies about the structure of Drosophila melanogaster retinal cell using electron microscopy have been carried out in details since 1960s. However, these results can have limitations in functional research because of two-dimensional structure. In this study, the adult retina of Drosophila melanogaster was investigated by employing high pressure freezing method, serial sections, high voltage electron microscopy, and 3-dimensional reconstruction method. From there results, mitochondria, microtubules, and nuclei were reconstructed as 3-dimensional structure using IMOD program. The 3D structure of these organelles showed that mitochondira mainly located in distal region near lens, and microtubule mainly located in distal and basal region. The 3D reconstruction of these organelles can be used for a critical evaluation in the dynamic change of cellular organelles caused by functional abnormality like retinal degeneration.

Typology of Young Korean Adults' Relationships with their Parents from an Intergenerational Solidarity Lens (청년의 세대관계 유형화: 세대 간 결속의 하위차원을 중심으로)

  • Lee, Jaerim;Park, Jane;Kim, Hyeji;Oh, Sangmin;Kwon, Soyoung
    • Human Ecology Research
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    • v.58 no.1
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    • pp.43-60
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    • 2020
  • The literature on parent-child relationships in young adulthood lacks a systemic approach that considers the multifaceted nature of intergenerational relationships. In this paper, we identify the latent profiles of young Korean adults' relationships with their parents based on the six dimensions of intergenerational solidarity (structural, associational, affectual, consensual, functional, and normative solidarity) as indicators. We considered solidarity for the mother and the father separately for structural, associational, affectual, and consensual dimensions. In terms of functional and normative solidarity, we measured both upstream and downstream intergenerational support. The sample included 1,015 young adults who were 19-34 years old, never married, not in secondary school, and had both parents living. The latent profile analysis revealed four profiles: (a) independent but intimate (22.7%), (b) coresident, outwardly intimate (32.4%), (c) detached from father (6.7%), and (d) coresident, intimate (38.2%). The factors that predicted each profile included the young adults' education, income, subjective socioeconomic status, and experiencing the features of emerging adulthood along with the parents' marital status, father's employment, and overparenting. The "coresident, intimate" group reported significantly higher levels of life satisfaction and fewer depressive symptoms compared to the other three groups. The lowest levels of psychological adjustment were found in the "coresident, outwardly intimate" group and "detached from father" group.

Development of Large-area Two-photon Stereolithography Process for the Fabrication of Large Three-dimensional Microstructures (대면적 3 차원 마이크로 형상제작을 위한 스테이지 스캐닝 시스템을 이용한 이광자 흡수 광조형 공정 개발)

  • Lim, Tae-Woo;Son, Yong;Yi, Shin-Wook;Kong, Hong-Jin;Park, Sang-Hu;Yang, Dong-Yol
    • Journal of the Korean Society for Precision Engineering
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    • v.25 no.1
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    • pp.122-129
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    • 2008
  • Two-photon stereolithography is recognized as a promising process for the fabrication of three-dimensional (3D) microstructures with 100 nm resolution. Generally, beam-scanning system has been used in the conventional process of two-photon stereolithography, which is limited to the fabrication of micro-prototypes in small area of several tens micrometers. For the applications to 3D high-functional micro-devices, the fabrication area of the process is required to be enlarged. In this paper, large-area two-photon stereolithography (L-TPS) employing stage scanning system has been developed. Continuous scanning method is suggested to improve the fabrication speed and parameter study is conducted. An objective lens of high numerical aperture (N.A.) and high strength material were employed in this system. Through this work, 3D microstructures of $600*600*100\;{\mu}m$ were fabricated.

In vitro Screening of Dietary Factors on Buckwheat(Fagopyrum esculentum Moench) Influencing the Regulation of Blood Pressure, Glucose and Cholesterol Level (혈압, 혈당 및 콜레스테롤농도 조절에 영향을 주는 식이 메밀인자의 in vitro 검정)

  • 최용순;김복란;김려화;이병훈;심태흠;이상영
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.2
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    • pp.280-287
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    • 2000
  • Generally, buckwheat has been regarded as a crop of secondary importance in many countries. In vitro functionalities of buckwheats as a food were evaluated in this study. Five of buckwheat cultivars were extracted with methanol, and the extractant were dried and lyophilized, separately. Or water soluble buckwheat components were digested with the commercial enzymes and the obtained protein hydrolysate was again fractionated by acid precipitation. The antioxidant capacity of the methanol extracts determined using Fe2+-ascorbic acid system was dependent ont the cultivars: The extract of Suwon 4 showed 3.3 times stronger activity than ascorbic acid in terms of IC50. Also, the extracts of buckwheats inhibited efficiently the activities of $\alpha$-amylase and lens aldose reductase. Buckwheat soluble protein or rutin suppressed the in vitro activities of angiotensin-converting enzyme, and the inhibitory degree depended largely on the cultivars. Buckwheat proteins exerted higher hydrophobicity being related to the sterol binding capacity than casein. The results suggested that buckwheat seeds may be desirable and functional food resources in human living in current society.

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Chemical Composition and Nutritional Characteristics of Lentils(Lens culinaris), and Their Application in the Food Industry: A Review (렌즈콩의 영양성분과 생리활성 및 식품산업의 응용)

  • Min, Myung-Ja;Shin, Hyun-Jae
    • Korean Journal of Food Science and Technology
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    • v.47 no.3
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    • pp.273-280
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    • 2015
  • Lentils (Lens culinaris) are a nutritious and popular food throughout the world. This review provides an overview of the nutritional and functional properties of lentils. Lentils have high nutritional value: high protein, high fiber, low fat, and a variety of minerals. The addition of lentils to other foods could enhance their health benefits. Additionally, there is no decrease in the amino acid content in lentils when cooked; rather, the amino acids increased and the phytic acids decreased. Lentils are generally known to have biomedical functions including antioxidative, anti-cancer, anti-inflammatory, antihypertensive, and thrombolytic properties. The data presented here show that fermentation would increase the amount of bioactive substances in the beans. Therefore, fermentation techniques could be a new approach to produce lentil-based foods. They are also eco-friendly, cost-effective, and feasible processes. This review has suggested a future development of new lentil-related foods using traditional fermentation technology.

Study of PSII-treated PMMA, PHEMA, and PHPMA ; Investigation of Their Surface Stabilities

  • Hyuneui Lim;Lee, Yeonhee;Seunghee Han;Jeonghee Cho;Moojin suh;Kem, Kang-Jin
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.204-204
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    • 1999
  • The plasma source ion implantation(PSII) technique which is a method using high negative voltage pulse in plasma system has the potential to change the surface properties of polymer. PSII technique increase the surface free energy by introducing polar functional groups on the surface so that it improves reactivity, hydrophilicity, adhension, biocompatability, etc. However, the mobility of polymer chains enables the modified surface layers to adapt their composition to interfacial force. This hydrophobic recovery interrupts the stability of modified surfaces to keep for the long time. In this study, poly(methyl methacrylate)(PMMA), poly(2-hydroxyethyl methacrylate)(PHEMA), and polu(2-hydroxypropyl methacylate)(PHPMA) for contact lens application, were modified to improve the wettability with PSII technique and were investigated the surface stabilities. Polymer film was prepared with solution casting(3 wt.% solution) and was annealed at 11$0^{\circ}C$ under vacuum oven to remove solvent completely and to eliminate physical ageing. The thickness of the film measured by scanning electron microscopy (SEM) and surface profilometer was about 10${\mu}{\textrm}{m}$. Polymers were treated with different kinds of gases, pulse frequency, pulse with, pulse voltage, and treatment time. Even though PMMA, PHEMA, and PHPMA have similar repeat unit structure, the optimal treatment conditions and the tendency to hydrophobic recovery were different. PHPMA, more hydrophilic polymer than PMMA and PHEMA showd better wettability and stability after mild treatment. Surface tensions were obtained by water and diiodomethane contact angle measurements to monitor the relation between hydrophobic recovery and polymer structure. Different ion species in plasma change the polar component and dispersion component of polymer surface. For better wettability surface, the increase of polar component was a dominant factor. We also characterized modified polymer surfaces using x-ray photoelectron spectroscopy(XPS), secondary ion mass spectrometry(SIMS), Fourier Transform infrared spectroscopy(FT-IR), and SEM.

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A Study on the Spatial effect of Phenomenological Light and Water in Architectural works of Steven Holl (스티븐 홀 작품에 나타난 현상학적 빛과 물의 공간작용)

  • 안우진;손광호;고성룡
    • Korean Institute of Interior Design Journal
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    • no.27
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    • pp.20-27
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    • 2001
  • The tendency of formalization in Contemporary Architecture deeply relies on the thought of Western Philosophy, which emphasizes the art of image perceived visually but ignores the body and perception of a human beig who uses the architecture and lives in it. On the contrary, Merleau-Ponty asserted long time ago that the world and the body are inseparably related to each other. The phenomenology is important in Architecture, since the center of thought should be taken back to the human body if a artistic meaning can be obtained by Architecture. From this point of view, the meaning of Contemporary Architecture can be renewed by the phenomenological idea of Merleau-Ponty as a means of expanding thought that overcomes the limit of formalization in Contemporary Architecture. This research aims to ream from Steven Holl's work, and show the Architectural elements that are used for preceptual experience of phenomenon and the function of those element sin Architectural space of his works. The result of study on about the phenomenal light and water in Architectural space of Steven Holl is as follows; First, in perceptional experience of phenomenon, time is an important element, which is successive and make a field that cause perceptional experience. Second, light, as a phenomenological element, acted as a means of expressing the comparison and change of light and shadow in Architectural space and showing the change of color by the diversity of time in inner space. Third, water, as a phenomenal lens, not only acted functional but also functioned as an element of sensual experience in Architectural space. It acted as an image containing time, space, just like a mirror that reflect the environment.

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Physical Properties of Styrene Copolymer and Contact Lens Application (스타이렌 공중합체의 물리적 특성 및 콘택트 렌즈로의 응용)

  • Kim, Tae-Hun;Ye, Ki-Hun;Sung, A-Young
    • Journal of the Korean Chemical Society
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    • v.53 no.6
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    • pp.755-760
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    • 2009
  • Styrene is broadly used as a polymer and a copolymer and is useful in manufacturing contact lenses due to its high refractive index. This study used styrene with the cross-linker EGDMA (ethylene glycol dimethacrylate), HEMA (2-hydroxyethyl methacrylate) and the initiator AIBN (azobisisobutyronitrile) for copolymerization. Measurement of the physical characteristics of the copolymerized material showed that the refractive index is 1.4412 - 1.4628, water content 20 - 35%, visible transmittance 82.6 - 87% and the tensile strength 0.143 - 0.344 Kgf. Also, measurements showed that the refractive index and tensile strength increased while the water content decreased as the ratio of styrene increased. Based on the results of this study, the produced copolymer can be estimated to be suitable for use as a material for high performance functional contact lenses.

Method to Evaluate Fabric Contamination Due to Fine Dust (섬유소재의 미세먼지 오염도 평가 방법 개발에 관한 연구)

  • Hwang, So-Young;Kwon, Jin-Kyung;Kim, Young-Sil;Choi, Eun-Jin;Kim, Da-Jin;Kim, Min;Yook, Se-Jin
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.20 no.11
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    • pp.86-91
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    • 2021
  • Recently, functional clothes that can reduce deposition and/or penetration of fine dust have been developed. However, there are no methods to quantitatively evaluate the performance of these clothes. In this study, we developed a method to contaminate a fabric using fine dust and established an approach to quantitatively assess the degree of particle contamination on the fabric surface. Silicate powder was chosen as the particle to simulate fine dust because silicate particles are fluorescent under UV light; therefore, they can be distinguished from any color of non-fluorescent fabric surface. A camera with a high-resolution lens system was used to scan the surface of the contaminated fabric surface, and the degree of particle contamination of the fabric surface was analyzed in terms of the pixels corresponding to the area of the fabric surface contaminated by silicate particles. Finished or unfinished nylon fabrics as well as cotton fabrics were contaminated with silicate particles, and their surfaces were scanned using the established camera. The proposed assessment method was found to be useful for quantitatively comparing the degree of particle contamination of the fabrics.