• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.3
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• pp.241-246
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• 1992

To clarify the requirement of L-ascorbic acid (AsA) in collagen synthesis, the incorporation of 1-$^{14}$ C-proline into the tissues of guinea pigs and the specific radioactivity ratio (proline/hydroxyproline) in collagen were investigated. Male guinea pigs maintained on the AsA-deficient diet were divided into three groups ; group A (AsA-deficient animals) : group B (control animals) supplemented with 5mg AsA/day ; group C (high dose animals) with 300mg AsA/day, and orally supplemented with or with-out AsA for 14 days. Collagen synthesis was estimated by measuring the incorporation of labeled pro-line into collagen in lung and dorsal skin, and the hydroxyproline contents in lung and skin. The AsA contents in the tissues were determined by high-peforrnance liquid chromatography (HPLC), and serum alkaline phosphatase activity was also measured. The serum alkaline phosphatase activity of AsA deficient group was very low as compared with those of AsA supplemented group. Incorporation of labelled proline into collagen and its specific radioactivity ratio in collagen increased with increasing levels of AsA in the tissues. There was a significantly positive relationship between the levels of AsA and hydroxyproline in the tissues.

• 전기의세계
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• v.28 no.4
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• pp.53-63
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• 1979

Interface recombination velocity in $Al_{x}$G $a_{1-x}$ As-GaAs and $Al_{0.85}$, G $a_{0.15}$ As-GaA $s_{1-y}$S $b_{y}$ heterojunction systems is studied as a function of lattice mismatch. The results are applied to the design of highly efficient III-V heterojunction solar cells. A horizontal liquid-phase epitaxial growth system was used to prepare p-p-p and p-p-n $Al_{x}$G $a_{1-x}$ As-GaA $s_{1-y}$S $b_{y}$-A $l_{x}$G $a_{1-x}$ As double heterojunction test samples with specified values of x and y. Samples were grown at each composition, with different GaAs and GaAs Sb layer thicknesses. A method was developed to obtain the lattice mismatch and lattice constants in mixed single crystals grown on (100) and (111)B oriented GaAs substrates. In the AlGaAs system, elastic lattice deformation with effective Poisson ratios .mu.$_{eff}$ (100=0.312 and .mu.$_{eff}$ (111B) =0.190 was observed. The lattice constant $a_{0}$ (A $l_{x}$G $a_{1-x}$ As)=5.6532+0.0084x.angs. was obtained at 300K which is in good Agreement with Vegard's law. In the GaAsSb system, although elastic lattice deformation was observed in (111) B-oriented crystals, misfit dislocations reduced the Poisson ratio to zero in (100)-oriented samples. When $a_{0}$ (GaSb)=6.0959 .angs. was assumed at 300K, both (100) and (111)B oriented GaAsSb layers deviated only slightly from Vegard's law. Both (100) and (111)B zero-mismatch $Al_{0.85}$ G $a_{0.15}$As-GaA $s_{1-y}$S $b_{y}$ layers were grown from melts with a weight ratio of $W_{sb}$ / $W_{Ga}$ =0.13 and a growth temperature of 840 to 820 .deg.C. The corresponding Sb compositions were y=0.015 and 0.024 on (100) and (111)B orientations, respectively. This occurs because of a fortuitous in the Sb distribution coefficient with orientation. Interface recombination velocity was estimated from the dependence of the effective minority carrier lifetime on double-heterojunction spacing, using either optical phase-shift or electroluminescence timedecay techniques. The recombination velocity at a (100) interface was reduced from (2 to 3)*10$^{4}$ for y=0 to (6 to 7)*10$^{3}$ cm/sec for lattice-matched $Al_{0.85}$G $a_{0.15}$As-GaA $s_{0.985}$S $b_{0.015}$ Although this reduction is slightly less than that expected from the exponential relationship between interface recombination velocity and lattice mismatch as found in the AlGaAs-GaAs system, solar cells constructed from such a combination of materials should have an excellent spectral response to photons with energies over the full range from 1.4 to 2.6 eV. Similar measurements on a (111) B oriented lattice-matched heterojunction produced some-what larger interface recombination velocities.ities.ities.s.

• Journal of Nutrition and Health
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• v.30 no.6
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• pp.639-647
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• 1997

The effect of excess L-ascorbic acid(AsA) in blood, liver lipid levels and peroxidation status were investigate . Ten Sprague-Dawley male rats weighing 150-200g were fed 300mg AsA/100g body weight/day, mixed into ground chow diet, for 4 weeks. And another set of then rats were fed only chow diet as the control. Average body weight gain was slightly lowered by AsA feeding without food intake change. The AsA group showed higher AsA levels in plasma and liver than the control group. In addition, the AsA group showed a higher plasma TBARS value. Liver TBARS seemed to be elevated in the AsA, but not significantly. The hemolysis of red cells tended to increase with excess AsA, accompanied by a raised GSH-Px activity and lowered total GSH levels. Plasma HDL-Chol level was increased while the levels of total Chol, LDL-plus VLDL-Chol , and triglyceride were unchanged . Atherogenic index decreased. Hepatic TG levels were also decreased, but the total amount of Chol increased slightly . Platelet TXA$_2$ production was inhibited by excess AsA feeding. Above results indicafe that oral feeding of excess AsA may be beneficial in reducing the risk of atherosclerosis ; however such practice may be detrimental for tissue lipid peroxidation and weight gain.

• Journal of radiological science and technology
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• v.28 no.4
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• pp.267-272
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• 2005

The effects of As addition in amorphous selenium (a-Se) films for digital X-ray conversion material have been studied using the moving photocarrier grating (MPG) technique. This method utilizes the moving interference pattern generated by the superposition of the two frequency shifted laser beams for the illumination of the sample. This moving intensity grating induces a short circuit current, jsc in a-Se:As film. The transport parameters of the sample are extracted from the grating-velocity dependent short circuit current induced in the sample along the modulation direction. The electron and hole mobility, and recombination lifetime of a-Se films with arsenic (As) additions have been obtained. We have found an increase in hole drift mobility and recombination lifetime, especially when 0.3% As is added into a-Se film, whereas electron mobility decreases with As addition due to the defect density. The transport properties for As doped a-Se films obtained by using MPG technique have been compared with X-ray sensitivity for a-Se:As device. The fabricated a-Se(0.3% As) device film exhibited the highest X-ray sensitivity out of 5 samples.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.7
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• pp.731-737
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• 2006

Four well-characterized soils collected from A- and B-horizon in the Department of Energy Oak Ridge Reservation in USA, mainly distributed with Inceptisol(Inc) and Ultisol(Ult) soils, were used in this work. The bioaccessibility of arsenic as well as oxidation phenomena of As(III) was investigated with soils spiked with As(III) and As(V) using a physiologically based extraction test(PBET) at pH 1.5 and 1:100 soil to solution ratio. Also effect of aging time on the bioaccessibility of arsenic was investigated over the 6 months. After 48 hours(fresh) contacting As(V) solution with soils, all soils rapidly and strongly sequestrated As(V), especially Ult-B. However, little sequestration was observed after 3-months. When As(III) was spiked on the same soils, a great portion of As(III) was oxidized to As(V) after 48 hrs, especially Inc-A and Ult-A soils, which is strongly related with Mn content in soils. By using As(III)-spiked soils, much reduced bioaccessibility as total arsenic was observed from Inc-B and Ult-B soils over the 6 months aging time compared to that from Inc-A and Ult-A soils. This result can be explained by the continuous sequestration of As(V), produced from oxidation of As(III), onto Inc-B and Ult-B soils having much amount of iron. The trend of As(III) sequestration over six months aging time was quite similar with that of As(V) sequestration.

• Journal of The Korean Association For Science Education
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• v.26 no.5
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• pp.637-645
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• 2006

This study reviewed and discussed the nature of scientific hypothesis described in philosophy, the philosophy of science, science, and science education. In these descriptions, a hypothesis was defined as one of five types: hypothesis as an assumption, hypothesis as a prediction, hypothesis as a tentative explanation, hypothesis as a tentative law, and hypothesis as a tentative causal explanation. Most scholars agreed that a hypothesis is a proposition or a set of propositions proposed as an explanation for an observed situation. In this view, a hypothesis is a possible answer to or an explanation of a question that accounts for all the observed facts. Also, it is a statement that explains why things happen in nature or an explanation for an observation that can be tested. In the five types of hypothesis meanings, a tentative explanation includes a tentative law and a tentative causal explanation. However, tentative laws are not explanation but description which are general statements drawn from specific experiences by way of a process known as induction. A number of studies also have distinguished hypothesis from assumption, tentative explanation, tentative law, and prediction. Therefore, a hypothesis is concluded to be a proposition or a set of propositions proposed as a tentative causal explanation for an observed situation.

• Journal of English Language & Literature
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• v.53 no.2
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• pp.219-241
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• 2007

This study takes its point of departure from Lacanian psychoanalysis and explores the point that an irremediable gap in the human subject can be illuminated in terms of the Lacanian categories, fantasy, symptom, gaze or voice as cause of desire of the Other. With respect to the category of the symptom, Lacan claims that the Other is always already there in the constitution of the subject, that is, the relation of the subject to the Other that is overwhelming as well as attracting the subject. Chapter II deals with the unthought, excessive ground of the conscious that borders on the subject, as is the case of self-excentric aspect of the man. Indeed, in Lacan's early work, the subject is essentially a relationship to the Other as desire(objet petit a), and there is no such thing as a symptom or fantasy without some subjective involvement. Lacanian unknown real, perpetual excess as the cause of desire animates the subject even as it threatens to blast it apart. The structures that establish the lines of desire in every individual are derived from an ineluctably intersubjective field. The Other is always already there in the constitution of the subject. In the final years of Lacan's teaching we find a kind of universalization of the symptom and almost everything that is becomes in a way symptom. Symptom, embodied in Laura in "Goblin Market," is her only substance, the only positive support of her being. By looking at the Laura's symptom in chapter III we gain an insight into the forbidden domain, into a real space that should be left unseen and unthought. The voice of goblin men therefore functions as a sublime object that is animating as well as dominating element even as it threatens to disintegrate the subject. Objet petit a as a sublime object that must be excluded in reality returns in the real, taking on a certain materiality which has an effect on Laura, that is, animates Laura's desire. Objet petit a is a real object, signifying nothing. In conclusion, the theoretical importance of Lacanian psychoanalysis is the relation between a subject and an Other as Objet petit a.

• Cross-Cultural Studies
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• v.33
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• pp.193-239
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• 2013

A photograph, which was applied to contemporary art, plays a very important role in the whole of the multiplied and diversified contemporary arts today. The application of photos, which were shown in contemporary art following the 1950s, can be classified into five types according to role and function of a photo in the process of developing a work. However, this classification is shown a little ambiguously. That is because photos of being utilized by artists are indicated very diversely depending on their artistic strategy and situation. As the first type, a few painters utilize a photo as mirror of reality in order to materialize a challenging and revolutionary idea with going against traditional picture in their pictorial practice. As the second classification, especially American painters utilize a photo as material component of forming their picture like photo-montage or collage. The combined application of this medium is first doing genre de-construction and hybridization of post-modernism in the 1980s while ultimately aiming at social criticism or political satire. The third type implies particularly a case that avant-garde artists utilize a photo as evidence of a work. In this case, a photo is employed as evidence of a work, which disappears in the temporal space essentially like body art, land art, and performance. Also, as the fourth type is a case of utilizing a photo for artistic concept of a work, not pictorial practice of picture, it is utilized often as important artistic strategy of conceptual artists. The final type of utilizing photo is a case of applying photo as formative tool on behalf of dye-stuffs or crayon in order to record a section of reality, which always continues regardless of event or meaning any more, in the traditional picture. In this case, a work is indicated as a photo of having a form of picture, namely, as Forme-tableau. The main subject is indicated there as a daily case of being repeated always the extremely common and revived theme.

• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.622-626
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• 1991

Antioxygenic effects of browning reaction product(BRP) obtained from 2M L-ascorbic acid(AsA) solution by heating at $85^{\circ}C$ were investigated. BRP obtained from AsA solution(pH 2.30) without pH adjusting showed slightly antioxygenic effect. As heating time increased, powers of antioxygenic activity of BRP did not increase. Retained AsA after heating did not effect antioxygenic activity of AsA solution. After adjusting pH of AsA solution to 2.3, 4.0, 7.0, 9.0 and 11.5 respectively, BRP were obtained from these AsA solution by heating at $85^{\circ}C$ for 15 hrs. Among these BRPs, BRPs of pH 2.3 and 4.0 showed no antioxygenic effect, lower browning degree and higher retained AsA, but had stronger reducing power. While those of pH 7.0, 9.0 and 11.5 had stronger antioxygenic activity, higher browing degree and lower retained AsA, but showed weaker reducing power. After adjusting pH of AsA solution to 7.0, antioxygenic activities of BRP which was obtained from this AsA solution by heating respectively at $85^{\circ}C$ for 0, 3, 5, 10, 15 and 25 hrs increased in proportion to heating time.

• Journal of the Korean housing association
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• v.4 no.2
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• pp.63-71
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• 1993

This study is to find mental element and principle for building as the side of tranditional ideas and to understand dwelling from and style by this wag. So we can understand yang taeg theory as a part of feng shui that controls the mental, field of traditional architecture. The results may besummarised as follows. 1. Mentalprinciple of traditional architecfure being understood as a "역" is to result is not the concept of shape as materials and in but that of phase as a spririt. 2. In yang taeg theory, architectural behavior (as selecting site, building and the day for building) is made form the base of that, a human being as a part of universe. 3. Geomantic aspect, to being, laid in an fying a human being and nature as spatial, time concept. 4. The concept of domain in feng-shui is found in village as well as in house.