• Title/Summary/Keyword: light adaptation

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DENTIN PERMEABILITY CHANCE ACCORDING TO THE PROCESS OF COMPOMER RESTORATION (컴포머 충전과정에 따른 상아질 투과도의 변화)

  • Cho, Hye-Jin;Lee, Kyung-Ha;Lee, Se-Joon;Lee, Kwang-Won
    • Restorative Dentistry and Endodontics
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    • v.27 no.4
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    • pp.382-388
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    • 2002
  • Compomer is composed of matrix and filler : matrix is made of the combination of resins and polycarboxylic molecules that are light-cured, and a filler is a glass component which is capable of ion-release. The resin content of compomers produces polymerization shrinkage which can adversely affect marginal adaptation. Pretreatment is a fundamental step which is treated with conditioner or primer in the use of these materials. Microleakage of restorative materials has been investigated mostly by dye penetration method. Dye penetration method was not quantitative and not measured repeatedly. Fluid filtration method, introduced and developed by Pashley's group, has been extensively used for 20 years for research purpose to understand the physiology of dentin, as well as the effects of various restorative treatments on dentin permeability. It permits quantitative, nondestructive measurment of microleakage in a longitudinal manner. The purpose of this study was to evaluate the change of dentin permeability according to the process of compomer restoration. In this study. Cl V cavities were prepared on buccal surface of thirty extracted human molars. The prepared cavities were etched by 37% phosphoric acid. The experimental teeth were randomly divided into three groups. Each group was treated with following materials Group 1 : Prime & Bond NT/Dyract AP, Group2: Single Bond/F2000 compomer, Group 3 : Syntac Single Component/Compoglass. The bonding agent and compomer were applied for each group following manufacturers information. Dentin permeability of each group was measured at each process by fluid filtration method; Step 1 : preparation(smear layer). Step 2 : etching(smear layer removal), Step 3 : applying the bonding agent, Step 4 : filling the compomer. Dentin permeability was expressed by hydraulic conductance ($\mu\textrm{l}$ min$^{-1}$cm$H_2O$$^{-1}$). The data were analysed statistically using One-way ANOVA and Sheffe's method. The results were as follows : 1. Dentin permeability differences between each process were significant except between step 1 and step 2(p<0.01). 2. Dentin permeability after removal of smear layer was highly increased(p<0.01). 3. In most case, decrease of dentin permeability was obtained by applying bonding agent(p<0.01). 4. Dentin permeability differences among the experimental groups were not significant(p>0.05). 5. None of compomers used in this study showed perfect seal at the interface.

Application of Remote Sensing and Geographic Information System in Forest Sector (원격탐사와 지리정보시스템의 산림분야 활용)

  • Lee, Woo-Kyun;Kim, Moonil;Song, Cholho;Lee, Sle-gee;Cha, Sungeun;Kim, GangSun
    • Journal of Cadastre & Land InformatiX
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    • v.46 no.2
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    • pp.27-42
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    • 2016
  • Forest accounts for almost 64 percents of total land cover in South Korea. For inventorying, monitoring, and managing such large area of forest, application of remote sensing and geographic information system (RS/GIS) technology is essential. On the basis of spectral characteristics of satellite imagery, forest cover and tree species can be classified, and forest cover map can be prepared. Using three dimensional data of LiDAR(Light Detection and Ranging), tree location and tree height can be measured, and biomass and carbon stocks can be also estimated. In addition, many indices can be extracted using reflection characteristics of land cover. For example, the level of vegetation vitality and forest degradation can be analyzed with VI (vegetation Index) and TGSI (Top Grain Soil Index), respectively. Also, pine wilt disease and o ak w ilt d isease c an b e e arly detected and controled through understanding of change in vegetation indices. RS and GIS take an important role in assessing carbon storage in climate change related projects such as A/R CDM, REDD+ as well. In the field of climate change adaptation, impact and vulnerability can be spatio-temporally assessed for national and local level with the help of spatio-temporal data of GIS. Forest growth, tree mortality, land slide, forest fire can be spatio-temporally estimated using the models in which spatio-temporal data of GIS are added as influence variables.

Effects of Sodium Alginate and Cellulose on Gastrointestinal Physiology in Rats (Sodium Alginate와 Cellulose가 흰쥐의 소화생리에 미치는 영향)

  • 송영선;양정례;서명자
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.25 no.4
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    • pp.551-559
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    • 1996
  • To examine the effects of dietary fibers on gastrointestinal physiology, rats were fed with diets containing 10% sodium alginate,10% cellulose, or fiber-free diets for 5 weeks. The results obtained were as follows: The chronic consumption of sodium alginate induced a significant decrease in body weight gain and feeding efficiency, but a significant increase in length and weight of small intestine. Fecal bulk and weight were higher in fiber-fed group than fiber-free group. The chronic consumption of dietary fiber induced a significant increase in fecal output, resulting in tile decrease of apparent digestibility of protein and lipid. Pancreatic protease activity was lower in fiber-fed group than fiber-free group, whereas pancreatic amylase and lipase activities were not affected. Scanning electron microscopy(SEM) and light microscopy(LM) studies showed small intestine microvilli with numerous ridges and convolutions and goblet cells in fiber-fed groups. As a result of this study, it is concluded that the chronic consumption of dietary fiber decreases apparent digestibility of nutrients and induces morphological and biochemical adaptation of digestive organs.

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The Effects of Tunnel Geometrical Characteristics and Canopy Installation on the Ventilation and Fire Propagation (터널의 기하학적 형태 및 캐노피 설치가 터널 환기 및 화재 확산에 미치는 영향 분석)

  • Lee, Chang-Woo;Suh, Ki-Yoon;Kim, Jung-Wook
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.8 no.4
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    • pp.325-334
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    • 2006
  • Understanding the airflow characteristics within the canopy structure installed between closely adjacent tunnels either for light adaptation or for protection from snow hazards is required for the normal ventilation as well as safety system design. Grade, horizontal alignment, cross-sectional area and shape are known to substantially influence the fire smoke behavior and their influences raise great concern for the safety design. This paper aims at studying the effects of tunnel geometrical characteristics and canopy installation on the ventilation and fire propagation through CFD analysis. In the case of 145m long canopy, 50% opening ratio is preferred with respect to the airflow pattern and ventilation efficiency. When a 20MW fire occurs in a 1.8km-long tunnel and four 1250mm reversible jet fans are instantly turned on, smoke concentration at 40m downstream of the fire decrease 13% for the upgrade tunnel with 2% gradient and increases 20% for -2% gradient, compared to the standard horizontal tunnel. Backlayering is observed within 45m-long segment toward the entrance in 2% down-graded tunnel. In a rectangular tunnel, there is no significant difference of smoke concentration as well as velocity profile from the standard crown tunnel. Three-laned tunnel shows lower level of both profiles and backlayering is detected up to 50m upstream of the fire, while the risky situation rapidly disappears thereafter.

An Analysis on the Empathic Changing Process of the Members in Empathy Training Program (공감훈련프로그램 참여아동의 공감표현 변화과정 분석)

  • Kim, Mi-Young
    • The Korean Journal of Elementary Counseling
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    • v.7 no.1
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    • pp.205-226
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    • 2008
  • The purpose of the study you have seen is to verify the effectiveness of existing quantitative research and to put the Empathy Training Program to practical use for participating children. From looking into this, the changes in empathic understanding that came to light in relationships between teacher and children and children and children are sure to have that effect. For this work, I established the following subject of inquiry: What kind of changing processes can be seen in the empathic understanding of participating children in the Empathy Training Program? To resolve the above line of inquiry, six female sixth grade elementary school students were chosen and they progressed through twelve sessions of the Empathy Training Program. The children were given a sentence completion exam, recognition work, neat writing exam and a school adaptation exam both before and after participation in the program, making data for analysis. To analyze, first, participants had one or two meetings of forty to fifty minutes each. Progress through the program's curriculum was recorded and through the repeating and copying method, to be sure participating children's empathic understanding was revealed, empathic language and behavior was routinely chosen. Next, according the above criteria I looked into visible changes of the participating children's empathic expressions, classifying and analyzing changes in empathic understanding and six instances of common changes in the emphatic understanding of the participants relationships were analyzed and put together. Next I will summarize the findings we have seen in this research: First, if we look into changes in common empathic understanding from the beginning, using the criteria of empathic language, each individual showed understanding at the beginning and passed and progressed through stages of care, insight and emotional expressions. Second, when we looked at the criteria of empathic behavior from the beginning to the end, one's line of vision and ability to concentrate one's attention was connected. Next, the act of nodding one's head looked like a brief nod at first but at the end, it was not just a simple nod but rather they could feel deep empathy. The condition and substance of the facial expression was seen to match and at the very end the child was expressive and stretched out arms to hold and pat the other person and the act of holding hands could also be seen. Among lots of empathic behavior the final stage was shown by half of the children. Third, from the first stage to the last stage there were many cases revealed. The more the children went the more complete their empathic language became. Their vocabulary increased and became more diverse with empathic actions. Also, when comparing actions and expressions from the beginning with the end, visible expressions became more natural and sincere at the end. The result of the research we have seen is that through receiving experience of empathic understanding, participating children showed a sense of self-confidence and they looked to make peaceful expressions while not being aggressive or defensive about problems. In addition, from understanding empathic expressions, participating children's relationships felt closer. This outcome within this group in this case will be applied and the formation of empathic understanding can be used by the children internally to solve their own problems, acquire close relationships with their teachers and others. It will also contribute to smooth classroom management.

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A Calculation Method of in vivo Energy Consumption in Estimation of Harvesting Date for High Potato Solids (고 고형분함량 감자의 수확시기 예측모형을 위한 식물체내 에너지 소모량 추정)

  • Jung, Jae-Youn;Suh, Sang-Gon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.55 no.4
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    • pp.284-291
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    • 2010
  • A simulation modeling for predicting the harvesting date with high potato solids consists of development of mathematical models. The mathematical model on potato growth and its development should be obtained by using agricultural elements which analyze relations of solar radiation quantity, temperature, photon quantity, carbon dioxide exchange rate, water stress and loss, relative humidity, light intensity, and wind etc. But more reliable way to predict harvesting date against climatic change employs in vivo energy consumption for growth and induction shape in a slight environmental adaptation. Therefore, to calculate in vivo energy loss, we take a concept of estimate of the amount of basal metabolism in each tuber on the basis of $Wm={\int}^m_tf(x)dt$ and $Tp=\frac{Tm{\cdot}Wm^{Tp}}{Wm^{Tm}}$. In the validation experiments, results of measuring solid accumulation of potato harvested at simulated date agreed fairly well with the actual measured values in each regional field during the growth period of 2005-2009. The calculation method could be used to predict an appropriate harvesting date for a production of high potato solids according to weather conditions.

Morphological Differentiation of the Trap in Aquatic and Terrestrial Utricularia Species (서식환경에 따른 통발속(Utricularia) 포충낭의 형태 분화)

  • Lee, Kyoung-Lan;Kim, In-Sun
    • Applied Microscopy
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    • v.40 no.4
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    • pp.237-244
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    • 2010
  • Utricularia forms small, but complex carnivorous trap along the stem either in water or in soil depending upon species. The shapes and sizes of the traps, appendages, and trichomes are known to differ among aquatic, terrestrial and epiphytic species. In the present study, the morphology and microstructure of the trap in aquatic Utricularia japonica and terrestrial U. livida were examined using light and electron microscopy. The aim of this study was to compare the characteristics of trap features between the aquatic and terrestrial species. The trap was found to be comprised of a thin walled bladder with numerous capitate trichomes, two-armed bifid and four-armed quadrifid glands in both species; however, the traps of the two species were different in size, and number and morphology of the trichomes and glands. Aquatic Utricularia was chlorenchymatous with chloroplasts distributed throughout the body, whereas the terrestrial species was translucent without plastids due to an adaptation to underground habitats. Furthermore, the former differed considerably in that the traps developed antenna and appendages around the entrance area. A peculiar trap entrance was also noted in U. livida, which exhibited radiating rows of various trichomes within funnel-shaped tissue. A large number of glandular trichomes covered the entrance area and door surface with four trigger hairs each in the aquatic form but only two in the terrestrial form. The glandular trichomes near the door secreted a large amount of mucilage that temporarily composed the velum in the U. japonica, however, it was not observed in the terrestrial species. All of the aforementioned features were highly related in their structure and function during carnivorous mechanism in Utricularia. The current findings provide important data for further comparison of the different life forms within Utricularia.

Individual Variation of Radiation Adaptive Responses in Patients Undergoing Imaging Studies Using $^{99m}Tc$ Labeled Radiopharmaceuticals ($^{99m}Tc$ 표지 방사성의약품을 이용한 핵의학 영상검사를 받은 환자에서 방사선 적응반응의 개인간 차이에 대한 연구)

  • Li, Ming-Hao;Bom, Hee-Seung;Kwon, An-Sung;Kim, Young-Ho;Kim, Ji-Yeul
    • Journal of Radiation Protection and Research
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    • v.28 no.2
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    • pp.117-125
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    • 2003
  • It was reported that radiopharamaceuticals induced radiation adaptive response (RAR) in patients undergoing nuclear medicine imaging studies. Individual variations of RAR were not studied well. The purpose of this study was to evaluate individual variation of RAR in patients undergoing nuclear medicine imaging studies. Peripheral lymphocytes were collected from 23 patients undergoing $^{99m}Tc-diethylenetriamine$ pentaacetic acid $(^{99m}Tc-DTPA)$ renal scintigraphy, 18 patients undergoing $^{99m}Tc-methylene$ diphosphonate $(^{99m}Tc-MDP)$ bone scintigraphy and 21 patients undergoing $^{99m}Tc-tetrofosmin\;(^{99m}Tc-TF)$ scintigraphy were collected before and 4 hours after injection of radiopharmaceuticals. The lymphocytes were exposed to challenge dose of 2 Gy gamma rays using a cell irradiator. Numbers of ring-form (R) and dicentric (D) chromosomes were counted under the light microscope. and used to calculate the frequency of chromosomal aberration [Ydr=(D+R)/total number of counted lymphocytes]. Adaptation index (k) was defined 3s ratio of Ydr in conditioned lymphocytes over Ydr in unconditioned lymphocytes. Coefficients of variance of k in $^{99m}Tc-DTPA,\;^{99m}Tc-MDP\;and\;^{99m}Tc-TF$ were 35%, 34% and 21%, respectively k was not dependent upon age, sex, and underlying diseases. There was a wide variation of RAR induced by radiopharmaceuticals among patients undergoing nuclear medicine procedures. It remains to be determined for causes of such variation.

A Study on the Diurnal Variation of Endorphin in Rat Brain (백서 뇌내 Endorphin의 일주기 변동에 관한 연구)

  • Jung, Chang-Young;Kim, Ki-Won;Cho, Kyu-Park
    • The Korean Journal of Pharmacology
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    • v.20 no.2
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    • pp.35-47
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    • 1984
  • Contents of immunoreactive ${\beta}-endorphin$ and maximum of $^3H-morphine$ binding was measured in the rat midbrain homogenates from different subgroups at 24 hour interval over 24 hours. Animals were adapted to the light-dark cycle(L : D, 12: 12) or constant darkness (D : D, 12 : 12) for 3 weeks. After the adaptation, 0.5ml of physiologic saline or drug was administered twice a day for 2 weeks. A highly significant circadian rhythm with the peak$(94.8{\pm}7.7\;fmole/mg\;protein)$ at 06:00 and the nadir $(27.6{\pm}2.4\;fmole/mg\;protein)$ at 18:00 was observed in constant of group. Constant dark or treatment of reserpine, pargyline, imipramine, amphetamine and chlorpromazine modified the diurnal rhythm in the time of peak and nadir, shape, phase amplitude and 24 hour mean of ${\beta}-endorphin$ contents. Opiate receptor binding by $^3H-morphine$ also showed highly significant diurnal change in control and constant dark adapted rats. Statistical analysis by one-way analysis of variance and two-way analysis of variance indicates that the·re are highly significant differences between the diurnal change of ${\beta}-endorphin$ in control and those constant dark adapted and drug treated groups. However diurnal change of Maximum $^3H-morphine$ binding is closely related to the change of ${\beta}-endorphin$ contents. The results are interpreted with regard to the circadian rhythm of beta-endorphin contents, its modification by psychoactive drugs and possible mechanism of diurnal change of opiate receptor in brain.

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A Study on the Circadian Rhythm of Opiate Receptor in Rat Brain (백서 뇌내 Opiate 수용체의 일주기 변동에 대한 연구)

  • Lee, Moo-Suck;Kim, Ki-Won;Cho, Kyu-Park
    • The Korean Journal of Pharmacology
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    • v.20 no.2
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    • pp.23-34
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    • 1984
  • To investigate diurnal variations of opiate receptor binding and its modification by experimental condition or treatment of various centrally-acting drugs, the amount of maximum $^3H-morphine$ binding in rat midbrain homogenates was measured at 4 hour intervals for 24 hours. Animals were conditioned under the controlled L : D, 12 : 12 cycle or D: D, 12 : 12 cycle, for 3 weeks and treated with 0.5 ml of physiological saline or drugs for 2 weeks. A highly significant diurnal rhythm with peak at 22 hour of early dark phase with an amplitude$(0.68{\pm}0.06\;pmole/mg\;protein)$ of +51.1% and nadir $(0.33{\pm}0.03\;mole/mg\;prtein)$ at 18 hour of late light phase with an amplitude of -26.6% was found in control group. 24 tour mean of $^3H-morphine$ binding was $0.45{\pm}0.03\;pmole/mg$ protein respectively. Constant dark adaptation or treatment of reserpine, pargyline, imipramine, amphetamine and chlorpromazine modified the diurnal rhythm in the time of peak and nadir binding shape, phase, amplitude of the diurnal curve and 24 hour mean of $^3H-morphine$ binding. However, Kd values were not changed in all experimental groups : Statistical analysis at times of least and great binding indicates that the differences in $^3H-morphine$ binding were due to changes not in the affinity, but in the number of binding sites. The results are interpreted with regard to the diurnal rhythm of opiate receptor finding. The modes of action of psychoactive drugs are closely related to postulated changes of receptor sensitivity in neuropharmacological aspects.

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