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The Prognostic Value of Fibroblastic Foci Quantity in Patients with Usual Interstitial Pneumonia (UIP 환자에서 측정된 Fibroblastic Foci량이 예후에 미치는 영향)

  • Park, Sung-Woo;Lee, Young-Mok;Lee, June-Hyeuk;Kim, Ki-Up;Kim, Do-Jin;Uh, Soo-Taek;Kim, Yong-Hoon;Park, Choon-Sik;Kim, Hyun-Jo;Youm, Wook
    • Tuberculosis and Respiratory Diseases
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    • v.51 no.6
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    • pp.540-549
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    • 2001
  • Background : Usual interstitial pneumonia (UIP) is a progressive fibrous lung disease with occasional fatal outcomes. However, the extent and rate of progression varies markedly from one patient to another. As a result, it is difficult to determine the time of the initial treatment and assess the disease activity and course. Fibroblast foci (FF) is well known to synthesize collagen actively by their myofibroblasts component. However, the prognostic value of the FF have not been evaluated in patients with VIP. Therefore this study was undertaken to determine how the number of fibroblastic foci can reflect the disease activity and progression. Methods: Twenty patients with UIP(M : F=13 : 7), who were diagnosed by a surgical lung biopsy. The number of fibroblastic foci was analyzed in terms of its correlation with the clinical manifostations, pulmonary function test, arterial blood gas analysis, and a bronchoalveolar lavage(BAL). Results : The number of fibroblastic foci did not correlate with the various lung function tests and the other clinical parameters. Interestingly, the percentage of neutrophils in the bronchoalveolar lavage fluid did correlate with the quantity of the normalized Vv of FF(r=0.60, p<0.05). The patients were divided into 2 groups, group I and II, arbitrarily, according to the value of the normalized Vv. The clinical parameters and the PIT results were not different between the two groups. In particular, the survival rate between the two groups according to the Kaplan-Meier analysis were not different. Conclusion : A large number of FF does not imply a bad prognosis in patients with UIP.

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Location and Linkages of Manufacturing in Jangyu-Myun, Kimhae-Gun (김해군 장유면의 공업입지와 지역적 연계)

  • Lim, Yeong-Dae
    • Journal of the Korean association of regional geographers
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    • v.4 no.1
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    • pp.99-120
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    • 1998
  • The purpose of this study is to clarify the industrialization process, and locational factors and linkages of manufacturing in Jangyu-Myun, a suburb of Metropolitan Pusan, toward which heavy decentralization of manufacturing from Pusan has been done. Hard data and soft data were used as the basic data. Hard data used for this study were both the statistical data which consists of the number of establishments and employee classified by product type, firm size, organizational type and unit area(dong) which were listed in statistics yearbooks, and the list of the owner's names, addresses, employee number, products and headquarters of firms which were listed in firm directories. Soft data were the results of the interviews with the 53 owners of firms surveyed among the firms selected by Proportional Stratified Sampling Method. The major findings were as follows: (1) Manufacturing location in Jangyu-Myun was regularized in 1980's in which decentralization of manufacturing was activiated. Though the industrialization of study area resulted from the birth, relocation and establishment of branches of the firms originated from the other regions, the relocation of small outer-oriented firms from the central city was the most important factor among them. (2) The main locational factors which induced the decentralizing manufacturing from the central city into Jangyu-Myun are closely related to land, transportation, personal factor, raw material suppliers and market. (3) The differences of important locational factors by the size and organizational type of firms are relevant to the characteristics of manufacturing location. (4) The changes of linkages attendant upon locational changes of firms were not so great and were localized in labor supply and marketing. (5) The strength of linkages is strong in the procurement of materials, in the subcontraction and in the marketing, but not in the ordering. (6) The main factors influencing on the formation of linkages are different by the types of linkages: monopolistic and oligopolistic supply are important in procurement linkages; characteristics of products and production capacity in the subcontraction and ordering; characteristics of products and the subsequent difficulties, in the marketing. (7) With the exception of procurement linkages, the strength of linkages with the outside of the study area are stronger than the linkages with the inside. The strength of linkages with the outside has distance-decay-function and strong linkages with the central city. (8) These spatial characteristics of linkages are different by products type, firm size and organizational type of firms: the spatial ranges of linkages are wider in the multi-location firms than in the single-location firms; the larger the firm size, the wider the spatial range of linkages: there is no consistent trend by products type. In conclusion, some facts described above were proved to be consistent with the results of proceeding studies in the other areas: influence of central city manufacturing relocation on industrialization in the suburb: different decentralization by products type, firm size and organizational types of firms: different locational factors by products type, firm size and organizational types of firms; linkage changes attendant upon locational changes of firms; spatial differences of linkages by products type, firm size and organizational type of firms. Some other factors were proved to be partly consistent: locational factors and spatial characteristics of linkages. Accordingly I think that the results of previous studies on the other areas can be applicable to the explanation of the location and linkage of manufacturing in Jangyu-Myun. For the better explanation on the characteristics of manufacturing decentralization from the central city, more empirical case studies on the location and linkage of manufacturing in the suburb areas are necessary.

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Development of a High Heat Load Test Facility KoHLT-1 for a Testing of Nuclear Fusion Reactor Components (핵융합로부품 시험을 위한 고열부하 시험시설 KoHLT-1 구축)

  • Bae, Young-Dug;Kim, Suk-Kwon;Lee, Dong-Won;Shin, Hee-Yun;Hong, Bong-Guen
    • Journal of the Korean Vacuum Society
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    • v.18 no.4
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    • pp.318-330
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    • 2009
  • A high heat flux test facility using a graphite heating panel was constructed and is presently in operation at Korea Atomic Energy Research Institute, which is called KoHLT-1. Its major purpose is to carry out a thermal cycle test to verify the integrity of a HIP (hot isostatic pressing) bonded Be mockups which were fabricated for developing HIP joining technology to bond different metals, i.e., Be-to-CuCrZr and CuCrZr-to-SS316L, for the ITER (International Thermonuclear Experimental Reactor) first wall. The KoHLT-1 consists of a graphite heating panel, a box-type test chamber with water-cooling jackets, an electrical DC power supply, a water-cooling system, an evacuation system, an He gas system, and some diagnostics, which are equipped in an authorized laboratory with a special ventilation system for the Be treatment. The graphite heater is placed between two mockups, and the gap distance between the heater and the mockup is adjusted to $2{\sim}3\;mm$. We designed and fabricated several graphite heating panels to have various heating areas depending on the tested mockups, and to have the electrical resistances of $0.2{\sim}0.5$ ohms during high temperature operation. The heater is connected to an electrical DC power supply of 100 V/400 A. The heat flux is easily controlled by the pre-programmed control system which consists of a personal computer and a multi function module. The heat fluxes on the two mockups are deduced from the flow rate and the coolant inlet/out temperatures by a calorimetric method. We have carried out the thermal cycle tests of various Be mockups, and the reliability of the KoHLT-1 for long time operation at a high heat flux was verified, and its broad applicability is promising.

The Search for Study on the Construction Process and Changes in the Landscape Plants of the Pasanseodang ('파산서당'의 영건과정과 조경식물 변화상 탐색)

  • Joo, Been;Choi, Hayoung;Shin, Sangsup
    • Korean Journal of Heritage: History & Science
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    • v.51 no.1
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    • pp.48-65
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    • 2018
  • The authors of this paper aim to make a record of the construction process, its symbolic meaning, and the changes in the status of the landscape plants at the Pasanseodang according to the Report on the Pasanseodang written by Park Gyu-hyun in 1874. First, the construction of Samgahun Pavilion, which is located in Myo-ri, Habin-myun, Dalsung-gun, Daegu, took about 90 years and spanned the lifetimes of Park Sungsoo, an 11th-generation descendant of Park Paengnyun (1417~1456) through to Park Kyuhyun, a 14th-generation descendant. It was called the shape of dragon, with its head facing the tail (回龍顧尾形), in feng shui. Second, the village of Pahwoe was founded in 1769, the 45th year of the reign of King Yeongjo, by Park Sungsoo for the purpose of socializing with his friends at his thatched home, and was named after his own courtesy name (Samgahun). Park Kwangseok, the second son of Park Sungsoo, built the sarangchae in 1826 and the anchae in 1869 after his marriage (in 1783). Then, Park Kyuhyun, the grandson of Park Kwangseok, built the pond and planted it with lotus flowers, and built the Hayeopjeong in 1874. The Pasanseodang, as the precursor of the Hayeopjeong, may be related with the name of the hillside region behind Samgahun. Third, a quadrangular-shaped pond with a length of 21m and a width of 15m was also built and planted with lotus flowers. In the center of the pond is a small round island that reflects the world view of the Chosun dynasty, i.e. that the sky is round and the landmass is quadrangular. Meanwhile, the name of the Hayeopjeon reflects the value system of aristocrats who lived a life of leisure and artistic indulgence. They called the eastern room "Yeeyeonhun" (怡燕軒) and the western room "Mongyangjae" (蒙養齋), names which embody their wishes for a good life as a member of the nobility and a bright future for one's descendants. Fourth, in Confucian terms, the authors infer the points of view reflected in the kinds of trees that were planted according to Confucian norms (pine tree, lotus, bamboo), the living philosophy of sustainability (willow), the ideology of seclusion and the search for peace of mind (bamboo), and relief efforts for the poor and a life of practicality (chestnut, oak, wild walnut, lacquer). The authors assert that this way of planting trees was a highly effective design feature of landscape architecture that drew on the locational and symbolic significance of the Seodang. Fifth, the majority of the trees that were initially planted withered and were replaced with different species, except for the locust and lotus, at this point. Nevertheless, a review of the process of construction, symbolic meaning, and original architectural landscape of the Samgahun is of value in demonstrating the extended symbolic meaning of their descendants in terms of the practical loss of the function of the Seodang, the values of Feng Sui (red in the east, white in the west, based on the principles of Feng Sui), the function of repelling evils spirits (kalopanax, trifoliate orange), aesthetic and practical values (sweetbrier, apricot, pear, peach, and oriental oak trees), and the prosperity of the family and the timeless value of honest poverty (silk, crape myrtle, and yew trees).

Association between Medial Temporal Atrophy, White Matter Hyperintensities, Neurocognitive Functions and Activities of Daily Living in Patients with Alzheimer's Disease and Mild Cognitive Impairment (알츠하이머병 및 경도인지장애 환자에서 내측두엽 위축, 대뇌백질병변, 신경인지기능과 일상생활 수행능력과의 연관성)

  • An, Min hyuk;Kim, Hyun;Lee, Kang Joon
    • Korean Journal of Psychosomatic Medicine
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    • v.29 no.1
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    • pp.67-76
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    • 2021
  • Objectives : The aim of this study was to compare activities of daily living (ADLs) according to degenerative changes in brain [i.e., medial temporal lobe atrophy (MTA), white matter hyperintensities] and to examine the association between neurocognitive functions and ADLs in Korean patients with dementia due to Alzheimer's disease (AD) and mild cognitive impairment (MCI). Methods : Participants were 111 elderly subjects diagnosed with AD or MCI in this cross-sectional study. MTA in brain MRI was rated with standardized visual rating scales (Scheltens scale) and the subjects were divided into two groups according to Scheltens scale. ADLs was evaluated with the Korean version of Blessed Dementia Scale-Activity of daily living (BDS-ADL). Neurocognitive function was evaluated with the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease assessment packet (CERAD-K). Independent t-test was performed to compare ADLs with the degree of MTA. Pearson correlation and hierarchical multiple regression analyses were performed to analyze the relationship between ADLs and neurocognitive functions. Results : The group with high severity of the MTA showed significantly higher BDS-ADL scores (p<0.05). The BDS-ADL score showed the strongest correlation with the word list recognition test among sub-items of the CERAD-K test (r=-0.568). Findings from the hierarchical multiple regression analysis revealed that the scores of MMSE-K and word list recognition test were factors that predict ADLs (F=44.611, p<0.001). Conclusions : ADLs of AD and MCI patients had significant association with MTA. Our study, which identifies factors correlated with ADLs can provide useful information in clinical settings. Further evaluation is needed to confirm the association between certain brain structures and ADLs.

Developments of Local Festival Mobile Application and Data Analysis System Applying Beacon (비콘을 활용한 위치기반 지역축제 모바일 애플리케이션과 데이터 분석 시스템 개발)

  • Kim, Song I;Kim, Won Pyo;Jeong, Chul
    • Korea Science and Art Forum
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    • v.31
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    • pp.21-32
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    • 2017
  • Local festivals form the regional cultures and atmosphere of communication; they increase the demand of domestic tourism businesses and thus, have an important role in ripple effects (e.g. regional image improvement, tourist influx, job creation, regional contents development, and local product sales) and economic revitalization. IoT (Internet of Thing) technologies have been developed especially, beacon-one of the IoT services has been applied as plenty of types and forms both domestically and internationally. However, notwithstanding expansion of current digital mobile technologies, it still remains as difficult for the individual to track the information about all the local festivals and to fulfill the tourists' needs of enjoying festivals given the weak strategic approaches and advertisement activities. Furthermore, current festival-related mobile applications don't function well as delivering information and have numerous contents issues (e.g. ways of information delivery within the festival places, independent application usage for each festival, one time usage due to one time event). This research, based on the background mentioned above, aims to develop the local festival mobile application and data analysis system applying beacon technology. First of all, three algorithms were developed, namely, 'festival crowding algorithm', 'visitor stats algorithm', and 'customized information algorithm', and then beta test was followed with the developed application and data analysis system. As a result, they could form the database of visitors' types and behaviors, and provide functions and services, such as personalized information, waiting time for festival contents, and 'hot place' function. Besides, in Google Play store, they also got the titles given with more than 13,000 downloads within first three months and as the most exposed application related with festivals; and, thus, got credited with their marketability and excellence. This research follows this order: chapter 2 shows the literature review of local festival related with technology development, beacon service, and festival application. In Chapter 3, design plans and conditions are described of developing local festival mobile application and data analysis system with beacon. Chapter 4 evaluates the results of the beta performance test to verify applicability of the developed application and data analysis system, and lastly, chapter 5 explains the conclusion and suggests the future research.

Studies on the Kiln Drying Characteristics of Several Commercial Woods of Korea (국산 유용 수종재의 인공건조 특성에 관한 연구)

  • Chung, Byung-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.2 no.2
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    • pp.8-12
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    • 1974
  • 1. If one unity is given to the prongs whose ends touch each other for estimating the internal stresses occuring in it, the internal stresses which are developed in the open prongs can be evaluated by the ratio to the unity. In accordance with the above statement, an equation was derived as follows. For employing this equation, the prongs should be made as shown in Fig. I, and be measured A and B' as indicated in Fig. l. A more precise value will result as the angle (J becomes smaller. $CH=\frac{(A-B') (4W+A) (4W-A)}{2A[(2W+(A-B')][2W-(A-B')]}{\times}100%$ where A is thickness of the prong, B' is the distance between the two prongs shown in Fig. 1 and CH is the value of internal stress expressed by percentage. It precision is not required, the equation can be simplified as follows. $CH=\frac{A-B'}{A}{\times}200%$ 2. Under scheduled drying condition III the kiln, when the weight of a sample board is constant, the moisture content of the shell of a sample board in the case of a normal casehardening is lower than that of the equilibrium moisture content which is indicated by the Forest Products Laboratory, U. S. Department of Agriculture. This result is usually true, especially in a thin sample board. A thick unseasoned or reverse casehardened sample does not follow in the above statement. 3. The results in the comparison of drying rate with five different kinds of wood given in Table 1 show that the these drying rates, i.e., the quantity of water evaporated from the surface area of I centimeter square per hour, are graded by the order of their magnitude as follows. (1) Ginkgo biloba Linne (2) Diospyros Kaki Thumberg. (3) Pinus densiflora Sieb. et Zucc. (4) Larix kaempheri Sargent (5) Castanea crenata Sieb. et Zucc. It is shown, for example, that at the moisture content of 20 percent the highest value revealed by the Ginkgo biloba is in the order of 3.8 times as great as that for Castanea crenata Sieb. & Zucc. which has the lowest value. Especially below the moisture content of 26 percent, the drying rate, i.e., the function of moisture content in percentage, is represented by the linear equation. All of these linear equations are highly significant in testing the confficient of X i. e., moisture content in percentage. In the Table 2, the symbols are expressed as follows; Y is the quantity of water evaporated from the surface area of 1 centimeter square per hour, and X is the moisture content of the percentage. The drying rate is plotted against the moisture content of the percentage as in Fig. 2. 4. One hundred times the ratio(P%) of the number of samples occuring in the CH 4 class (from 76 to 100% of CH ratio) within the total number of saplmes tested to those of the total which underlie the given SR ratio is measured in Table 3. (The 9% indicated above is assumed as the danger probability in percentage). In summarizing above results, the conclusion is in Table 4. NOTE: In Table 4, the column numbers such as 1. 2 and 3 imply as follows, respectively. 1) The minimum SR ratio which does not reveal the CH 4, class is indicated as in the column 1. 2) The extent of SR ratio which is confined in the safety allowance of 30 percent is shown in the column 2. 3) The lowest limitation of SR ratio which gives the most danger probability of 100 percent is shown in column 3. In analyzing above results, it is clear that chestnut and larch easly form internal stress in comparison with persimmon and pine. However, in considering the fact that the revers, casehardening occured in fir and ginkgo, under the same drying condition with the others, it is deduced that fir and ginkgo form normal casehardening with difficulty in comparison with the other species tested. 5. All kinds of drying defects except casehardening are developed when the internal stresses are in excess of the ultimate strength of material in the case of long-lime loading. Under the drying condition at temperature of $170^{\circ}F$ and the lower humidity. the drying defects are not so severe. However, under the same conditions at $200^{\circ}F$, the lower humidity and not end coated, all sample boards develop severe drying defects. Especially the chestnut was very prone to form the drying defects such as casehardening and splitting.

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Soil Water and Nutrient Movement Model Under Different Soil Water Conditions -I. Determination of Retardation and Hydrodynamic Dispersion Coefficient of Solute of an Unsaturated Sandy Loam Soil (토양수분(土壤水分) 분포(分布)에 따른 토양내(土壤內) 양수분(養水分) 이동(移動) 모형(模型) -I. 불포화(不飽和) 토양(土壤)에서 용질(溶質)의 이동지연(移動遲延)과 수리동적(水理動的) 분산계수(分散係數)의 측정(測定))

  • Jung, Yeong-Sang;Woo, Deog-Ki;Lim, Hyung-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.23 no.1
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    • pp.8-14
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    • 1990
  • Retardation and hydrodynamic dispersion coefficient necessary for model of water and solute movement in a soil were determined for horizontal soil column with different initial soil water conditions. The soil columns were compacted with sandy loam soil. The bulk density was $1,350+50kg/m^3$, and initial water contents were 0.05, 0.08 and 0.14. Advancement of 0.05% $CaSO_4$ solution was used as the standard and advancements of 0.5% KCl, $CaCl_2$ and $KH_2PO_4$ were compared. Retardation of non-reactive $Cl^-$ was related with the initial soil water content, ${\theta}n$, as ${\theta}/({\theta}-{\theta}n)$, and anion exclusion was ignored. Retardations of active $K^+$, $Ca^{{+}{+}}$ and $H_2PO_4{^-}$ were related as 1/(R+1) $^*{\theta}/({\theta}-{\theta}n)$, in which R was retardation coefficient. Measured R was 0.64 for $K^+$, 0.80 for $Ca^{{+}{+}}$ and 2.6 for $H_2PO_4{^-}$, respectively. Calculated R using Langmuir adsorption isotherm showed fair degree of applicability. Soil water diffusivity, $D({\theta}),m^2/sec$, calculated for different initial water content showed unique function as $$log(D({\theta}))=13.448{\theta}-9.288$$ Hydrodynamic dispersion coefficient of $Cl^-$ above soil water content 0.36 was similar to soil water diffusivity and decreased to near self diffusion coefficient at soil water content near 0.2. Those of $K^+$, $Ca^{{+}{+}}$ $H_2PO_4{^-}$ at soil water content of 0.38 were $5.5{\times}10^{-6}$, $2.4{\times}10^{-6}$ and $7.1{\times}10^{-7}m^2/sec$ and decreased rapidly with decreasing soil water content lower than 0.36.

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The Necessity and Requirement of Trial Lens Set Standardization (검안렌즈 표준화의 필요성과 규격에 관한 연구)

  • Park, Sang-Yeul
    • Journal of Korean Ophthalmic Optics Society
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    • v.11 no.3
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    • pp.217-223
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    • 2006
  • The purpose of this study is to provide improvements and standards of trial lens, in a situation that there is a lack of standards of trial lens set that have been used for self-conscious refraction test after helm refraction test at about 5,000 opticians, ophthalmologic clinics and hospitals, and contact-lens shops, that there is a lot of discrepancies between refraction specified and the actual power, and that there is no regulation of optical tolerance error. For the study, opticians who have used Trial lens set were asked to participate in a questionnaire survey through continuing education, and divided into those who have used domestic lens and those who have used imported lens, 5 opticians each for less than 5 years, 5 to 10 years, more than 10 years. The measurement of both refraction specified and the actual diopter was compared to Japan Industrial Standards(JIS T4402). As a result of comparative analysis, more than 80% of respondents have had reliability on the refraction of trial lens they had used, indicating that they have never measured the refraction specified and the actual diopter after buying them. Besides, Korean Industrial Standards(KS P4402) has been imperfect in diopter range since it was legislated in 1979. More than 95% of respondents have been unsatisfied with optometry. Also, it has indicated that refraction error is more frequent in long-term-used trial lens. The conclusion is that it is necessary to standardize trial lens set and that it is required to add lens to lens set provided under KS P4402. Moreover, it is necessary to have supervisory agency for a standardization of trial lens. I hope that both domestic lens and imported lens, as in German and Japan, will be tested to find whether they meet optical tolerance error and standard trial lens will be distributed. Good optic inspection is required for the improvement and management of eye health and optical function, and the same standard trial lens set should be used. whoever is tested. Also, I hope that trial lens set will be specified within standards and tolerance error.

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The Preparation and Physicochemical Properties of Dipalmitoylphosphatidylcholine/Cholesterol/Fluorinated Surfactant Vesicle Incorporated Fatty Acid Salt (불소화지방산염 첨가에 의한 디팔미토일포스파티딜콜린/콜레스테롤/불소화계면활성제 베지클의 제조와 물성 측정 연구)

  • Park, Young Ju;Kwon, Kyung Ok;Kim, Myung Ja
    • Applied Chemistry for Engineering
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    • v.9 no.3
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    • pp.457-461
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    • 1998
  • The vesicle system of DPPC(dipalmitoylphosphaticylcholine)/Chol(Cholesterol) has been modified by incorporating various mole fractions of flourinated surfactant($C_8F_{17}(CH_2)_2OCO-CH_2CH(SO_3Na)COO(CH_2)_2C_8F_{17}$. Sodium bis(1H,1H,2H,2H-heptadecaflurododecyl)-2-sulfosuccinate, FS)/fluorinated fatty acid salt ($C_7F_{15}COONH_4$, ammoniumpentadecaflurooctyrate, FFS), and their physicochemical properties have been investigated in an attempt to enhance the stability of phospholipid vesicle system. The ${\zeta}$-potential measurement by use of Zetamaster sub-micron Particle Electrophoresis Analyzer (Malvern Co.) showed that a charged homogeneous DPPC/Chol/FS vesicle has been formed owing to the incorporated FFS effect on the membrane, playing a role as a cosurfactant in the bilayer between DPPC and FS components. With increase in the concentration of FFS, it was found that the particle size and also surface charge of the DPPC/Chol/FS vesicle decreased. The stability of DPPC/Chol/FS/FFS liposome was found to be enhanced significantly compared to that of DPPC/Chol/FS according to the dispersity change as a function of time. The release rate of dye molecule of Methylene Blue from the DPPC/Chol/FS/FFS vesicle was determined to be slower than that of DPPC/Chol/FS system, and it may be attributed to the increase in microviscosity of the hydrophobic region in the bilayer. The affinfinity of DPPC/Chol/FS/FFS vesicles to albumin was found to be slightly lowered compared to that of DPPC/Chol/FS. Based on these findings, it was confirmed that a more stable and homogeneous vesicle system of DPPC/Chol/FS could be prepared by addition of FFS, acting as a cosurfactant in the aggregate formation.

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