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Effect of Fluoride Recharging on Fluoride Release and Surface Properties of Orthodontic Bracket Adhesives (불소 적용 후 교정용 브라켓 접착제 종류에 따른 불소 재흡수성과 표면 변화에 관한 연구)

  • Byeon, Seon Mi
    • Journal of dental hygiene science
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    • v.18 no.4
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    • pp.218-226
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    • 2018
  • The aim of this study was to compare fluoride release and surface changes according to different orthodontic bracket adhesives the application of fluoride products. We used non-fluoridated composite resin Transbond fluoridated composite resins Blugloo and LightBond, resin-modified glass ionomer Rely $X^{TM}$ Luting 2, and conventional glass ionomer Fuji $I^{(R)}$. Fluoride release of five orthodontic bracket adhesives and fluoride release ability after application of three fluoride products (1.23% acidulated phosphate fluoride gel, Tooth Mousse $Plus^{(R)}$, Fluor Protector, and a toothbrush with sodium fluoride-containing toothpaste) were measured using a fluoride electrode that was connected to an ion analyzer. After 4 weeks of fluoride application, the surface roughness and surface morphology were examined using a surface roughness tester and field emission scanning electron microscopy. The amounts of fluoride release were observed not only on application of Tooth Mousse $Plus^{(R)}$ and Fluor Protector on resin-modified glass ionomer Rely $X^{TM}$ Luting 2 and Fuji $I^{(R)}$, but also during tooth brushing using fluoride-containing toothpaste. After application of Tooth Mousse $Plus^{(R)}$, except Transbond XT, the surface roughness increased, and all orthodontic adhesives showed a partial drop of micro-particle filler. On application of 1.23% acidulated phosphate fluoride gel on all orthodontic bracket adhesives, their surface roughness increased. To bond the orthodontic bracket, resin-modified glass ionomer Rely $X^{TM}$ Luting 2 and Fuji $I^{(R)}$ adhesives are highly recommended if the amount of fluoride release is considered to confer a preventative effect on dental caries, and among the fluoride products, Tooth Mousse $Plus^{(R)}$ and Fluor Protector are better than 1.23% acidulated phosphate fluoride gel, and these are expected to prevent dental caries even during tooth brushing with fluoride-containing toothpaste.

Comparison of Mineral Contents of Three Rice Varieties under Different Cultural Practices (재배조건(이앙시기, 수확시기, 질소시비)별 쌀의 무기질 조성 비교)

  • Hwang, Hye-Rim;Kim, Kyoung-Hee;Lee, Jeong;Chung, Chong-Tae;Lee, Jae-Chul;Choi, Jong-Jin;Chun, Jong-Pil;Yook, Hong-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.6
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    • pp.721-726
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    • 2009
  • The objectives of this study were to analyze mineral contents of three rice varieties (Josangheugchal, Heugjinjubyeo and Dongjinchalbyeo) under three different cultural practices: five transplanting time (May 15, May 25, June 4, June 14, and June 24), five harvest times (30, 40, 50, 60, and 70 days) and N-fertilization levels (0.0, 4.5, 9.0, 13.5, and 18.0 kg/10a). Mineral contents of Josangheugchal were increased by late transplanting time with increased nitrogen level; however, it was not significantly different by harvest time. Heugjinjubyeo did not show significant difference in three cultivations. Mineral contents of Dongjinchalbyeo increased at the transplanting time of May 25 and June 14 and according to late harvest time. Also mineral contents of Dongjinchalbyeo that did not show significant difference except for calcium according to different nitrogen levels.

Behaviors of Arsenic in Paddy Soils and Effects of Absorbed Arsenic on Physiological and Ecological Characteristics of Rice Plant lll. Effect of Water Management on As Uptake and the Growth of Rice Plant at As Added Soil (토양중(土壤中) 비소(砒素)의 행동(行動)과 수도(水稻)의 비소흡수(砒素吸收)에 의(依)한 피해생리(被害生理) 생태(生態)에 관(關)한 연구(硏究);Ⅲ.물관리(管理)가 수도의 비소흡수(砒素吸收) 및 생육(生育)에 미치는 영향(影響))

  • Lee, Min-Hyo;Lim, Soo-Kill-H
    • Korean Journal of Environmental Agriculture
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    • v.6 no.1
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    • pp.1-6
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    • 1987
  • A pot experiment was conducted to find out the effect of water management on the growth and uptake of arsenic and inorganic nutrients of rice plant at As added soil. The arsenic were added to soil at the levels of As 0, 10, 50, 100 and 150 ppm, respectively. Water management was done with two ways: intermittent irrigation from ten days after transplanting, and continuous submersion until harvest. Higher soil As levels increased As content in plant but reduced growth rate. Aresenic content in plant was considerably reduced with intermittent irrigation compared to continuous submersion. Rice growth showed also same trend. With increasing As levels in soil, N content in plant was increased but P, K, Ca, Mg, $SiO_2$, Fe and Mn content in plant were tend to be decreased. These inorganic nutrients in plant were also much absorbed in continuous submersion compared to intermittent irrigation. Soil pH was slightly increased with increasing As levels in soil while soil Eh has no relationship with soil As levels. On the other hand, soil pH was higher in the treatment of continuous submersion than that of intermittent irrigation but soil Eh showed reverse trend. With increasing As levels in soil, water soluble-As and Ca-As fractions in soil tend to be increased with continuous submersion, but these fractions has no tendency with intermittant irrigation.

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Constitution of Formal and Informal Meals Consisting of Traditional Local Foods in Busan, Korea (부산지역 전통향토음식을 이용한 정식 및 별미식 식단 구성)

  • Kim, Hyeonsuk;Woo, Minji;Kim, Hyunju;Song, Yeong Ok
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.10
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    • pp.1467-1474
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    • 2012
  • The purpose of study was to introduce menus consisting of traditional local foods consumed in Busan, Korea. Five different types of formal meal menus with three side dishes and five different types of informal meal menus of which the main dish was not cooked rice were developed. Scores for the menu evaluations of formal and informal meals were higher than 7.9 (mean score of 6 category) on a 9.0 scale, suggesting that the menus were well constituted in terms of 'repeated use of ingredients and cooking methods', 'balance between main and side dishes', 'frequency of usage of local products', 'nutritional balance', 'variety of dishes', and 'popularization'. Nutritional values of menus were compared with those of the KDRI for men aged 30~49 years old. All ten menus reflected a low calorie, high protein, and high fiber diet. Mineral contents (Ca, Fe, Zn, K, and Na) of the above 10 menus were higher than those of the KDRI. On the other hand, vitamin contents slightly differed according to meal type due to limited fresh vegetable usage in the winter season. Vitamin A, B ($B_1$, $B_2$, niacin, $B_6$), C, folic acid, and E contents in the five informal menus were found to be proper or greater than those of the KDRI. However, for the formal meal menus, all vitamin contents except that of vitamin A in menu type I was lower than that of the KDRI. Content of vitamin C in menu type V was approximately 50% of that of the KDRI. The most preferred formal menu was consisted of Ogokbap, Boreumjijimi, Dongchimi, Namul (nine varieties), Gaksaeksanjeok (Shark/Daegu/Gunso), and Gimgui. And that for informal menu was consisted of Honghapjuk, Baechu kimchi, Dongchimi, Miyeokseolchi, Kodari jorim, and Neulgeun hobakjeon. Suggestions for providing more fresh vegetables or fruits for certain types of meals (formal meal type V) were offered. Additionally, pre-preparation of sea products were required to reduce Na contents.

The Effects of Carbonate Minerals in Gully-pot Sediment on the Leaching Behavior of Heavy Metals Under Acidified Environment (우수관퇴적물에 함유된 탄산염광물이 산성환경에서의 중금속 용출거동에 미치는 영향 평가)

  • 이평구;유연희
    • Economic and Environmental Geology
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    • v.35 no.3
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    • pp.257-271
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    • 2002
  • One of the main interests in relation to heavily contaminated gully-pot sediment in urban area is the short term mobility of heavy metals, which depends on the pH of acidic rainwater and on the buffering effects of carbonate minerals. The buffering effects of carbonates are determined by titration (acid addition). Leaching experiments are carried out in solutions with variable initial HN03 contents for 24h. The gully-pot sediment appears to be predominantly buffered by calcite and dolomite. In case of sediment samples, which highly contain carbonates, pH decreases more slowly with increasing acidity. On the other hand, for the sediment samples, which less contain carbonate minerals, pH rapidly drops until it reaches about 2 then it decreases slowly. The leaching reactions are delayed until more acid is added to compensate for the buffering effects of carbonates. The Zn, Cu, Pb and Mn concentrations of leachate rapidly increase with decreased pH, while Cd, Co, Ni, Cr and Fe dissolutions are very slow and limited. The solubility of heavy metals depends not only on thc pH values of leachatc but also on the speciation in which metals are associated with sediment particles. In slightly to moderately acid conditions, Zn, Cd, Co, Ni and Cu dissolutions become increasingly important. As deduced from leaching runs, the relative mobility of heavy metals at pH of 5 is found to be: Zn > Cd > Co > Ni > Cu » Pb > Cr, suggesting that moderately acid rainwater leach Zn, Cd, Co, Ni and Cu from thc contaminated gully-pot sediment, while Pb and Cr would remain fixed. The buffering effects of Ca- and Mg-carbonates play an important role in delaying as well as limiting the leaching reactions of heavy metals from highly contaminated gully-pot sediment. The extent of such a secondary environmental pollution will thus depends on how well the metals in sediment can be leached by somewhat acidic rain water. Changes in the physicochemical environments may result in the severe environmental pollution of heavy metals. These results are to be taken into account in the management of contaminated sediments during rainstorms.

Antioxidant Effect according to Extraction Method in Extracts of Dendranthema zawadskii var. yezoense and Cosmos bipinnatus (추출 방법에 따른 남구절초와 코스모스 추출물의 항산화 효과)

  • Woo, Jeong-Hyang;Shin, So-Lim;Chang, Young-Deug;Lee, Cheol-Hee
    • Horticultural Science & Technology
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    • v.28 no.3
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    • pp.462-468
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    • 2010
  • Top parts of $Dendranthema$ $zawaskii$ var. $yezoense$ (DZY) and $Cosmos$ $bipinnatus$ (CB) are believed to contain substances with antioxidant effects and activity. Present experiments were undertaken to investigate an adequate and efficient extraction method which ensures the highest yield of antioxidant components. Extraction yield was 1.11-1.92 times higher by ultrasonic method than other methods in both species. By 45 minute ultrasonic extraction, total polyphenol contents reached the highest level, $80.70mg{\cdot}g^{-1}$ tannic acid equiv./DW in $Cosmos$ $bipinnatus$ and total flavonoid contents $50.41mg{\cdot}g^{-1}$ naringin equiv./DW in DZY. DPPH radical scavenging activity was almost the same among extraction methods or slightly higher in reflux extraction. The highest DPPH radical scavenging was observed by reflux extract in CB ($RC_{50}=0.135mg{\cdot}mL^{-1}$). ABTS radical scavenging activity was the highest by 15 minute ultrasonic wave in DZY and CB, $RC_{50}=0.159mg{\cdot}mL^{-1}$ and $RC_{50}=0.139mg{\cdot}mL^{-1}$, respectively. High ferrous ion chelating effects were obtained by 30-minute ultrasonic wave in DZY ($RC_{50}=0.803mg{\cdot}mL^{-1}$). Extracts of top parts of DZY obtained by reflux method showed the highest inhibition effect against peroxidation of linoleic acid, and extract of CB obtained by ultrasonic for 45 minutes showed the highest inhibition effect. In conclusion, optimum extraction method should be adjusted according to plant species and antioxidant substances.

Food & Nutrition Survey of Specific Areas in Seoul Kores (서울시내 계층별 아파트 주민의 영양실태조사)

  • Kim, S.H.;Chung, C.E.;Lee, H.K.;Cho, S.S.;Lee, Y.W.
    • Journal of Nutrition and Health
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    • v.7 no.2
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    • pp.53-63
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    • 1974
  • For the elucidation of the nutritional status of residences of apartments located in various areas in Seoul city, the food and nutrition survey was undertaken by the graduate students from Department of Food & Nutrition, Ewha Womans University in 1973. The socioeconomic stratification was mainly considered for the selection of sample apartments included in this study. Hangang Mansion, KIST, Munwhachon & Bukahyun apts were selected in this respect. A. Common living circumstances. Through the questionaries, author concluded nutritional concept on everyday food life as follows; 1. Higher income seems less effective in everyday food life on the nutritional view point than higher education does. 2. It needs to be urgently improved to be accustomed to use exact measuring concept of foods when they cook. 3. It needs to be improved to serve meals for individual portion at meal table, because the portion control at meal table will effect to national food policy. B. Nutrition Survey. Average daily calroie intake was the highest in Hangang Mansion and lowest in Bukahyun apt., in accordance with their economic living standard, but most of their calorie intakes were lower than the R.D.A. (3000ca1 for male, 2200 Cal for female). But the composition ratio of the total calorie intake was near to the ideal, carbohydrate 60%, protein 15%, fat 25%. Although there were differences in their economic living situations in urban area, most people ingested relatively good quality and large amounts of protein and fat. Vitamin A and Niacine intake exceeded the R.D.A., but the intake of Ca, Thiamine, Riboflavin, Ascorbic Acid were far less than that of R.D.A. C. food Intake. Amounts of total daily food intake were highest in Bukahyun apt. and lowest in Hangang Mansion. These showed adverse aspects to the total calorie intakes and their income levels. The ratio of cereals, $40%{\sim}50%$ of the total food intake, was higher than any other kinds of foods in all apartments. Among the other foods except cereals, there represented the highest level of meats in Hangang Mansion and KIST apt., while intake of Kimchies were highest in Munwhachon and Bukahyun apt. In the case of vegetables and fruits intake, the ratio of them in Hangang Mansion and KIST apt. were high, on the other hand the ratio of starchy roots appeared lowest in Hangang Mansion. For the main sources of protein, meats were ingested in Hangang Mansion and KIST apt., meats and fishery were used in Munwhachon apt., and beans were eaten highly in their meals in Bukahyun apt. These food contents and distributions showed the significant differences not only their economic classes but also regional characteristics.

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A Novel Volumetric Method for Quantitation of Titanium Dioxide in Cosmetics (용량분석법을 이용한 화장품 중 티타늄옥사이드의 정량)

  • Kim, Young-So;Kim, Boo-Min;Park, Sang-Chul;Jeong, Hye-Jin;Chang, Ih-Seop
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.31 no.4 s.54
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    • pp.289-293
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    • 2005
  • Nowadays there are many sun protection cosmetics including organic or inorganic UV filter as an active ingredient. Chemically stable inorganic sunsEreen agents, usually metal oxides, we widely employed in high SPF products. Titanium dioxide is one of the most frequently used inorganic UV filters. It has been used as pigments for a long period of cosmetic history. With the development of micronization techniques, it becomes possible to incorporate titanium dioxide in sunscreen formulations without whitening effect and it becomes an important research topic. However, there are very few works related to quantitations of titanium dioxide in sunscreen products. In this research, we analyzed amounts of titanium dioxide in sunscreen cosmetics by adapting redof titration, reduction of Ti(IV) to Ti(III) and reoxidation to Ti(IV). After calcification of other organic ingredients of cosmetics, titanium dioxide is dissolved by hot sulfuric acid. The dissolved Ti(IV) is reduced to the Ti(III) by adding aluminum metals. The reduced Ti(III) is titrated against a standard oxidizing agent, Fe(III) (ammonium iron(III) sulfate), with potassium thiocyanate as an indicator In order to test accuracy and applicability of the proposed method, we analyzed the amounts of titanium dioxide in four types of sunscreen cosmetics, such as cream, make-up base, foundation and powder, after adding known amounts of titanium dioxide $(1{\sim}25w/w%)$. The percent recoveries of the titanium dioxide in four types of formulations were in the range between 96 and 105%. We also analyzed 7 commercial cosmetic products labeled titanium dioxide as an ingredient and compared the results with those of obtained from ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry), one of the most powerful atomic analysis techniques. The results showed that the titrated amounts were well coincided with the analyzed amounts of titanium dioxide by ICP-AES. Although instrumental analytical methods, ICP-MS (Inductively Coupled Plasma-Mass Spectrometry) and ICP-AES, are the best for the analysis of titanium, it is hard to adopt because of their high prices for small cosmetic companies. It was found that the volumetric method presented here gat e quantitative and reliable results with routine lab-wares and chemicals.

A Study on change in thermal properties and chemical structure of Zr-Ni delay system by aging (노화에 따른 Zr-Ni계 지연관의 열 특성 및 화학적 구조 변화에 관한 연구)

  • Park, Byung Chan;Chang, Il Ho;Kim, Sun Tae;Hwang, Taek Sung;Lee, Seungho
    • Analytical Science and Technology
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    • v.22 no.4
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    • pp.285-292
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    • 2009
  • It has been observed that, after long term storage, some ammunitions are misfired by tamping (combustionstopping) due to aging of the chemicals loaded in the ammunitions. Used in ammunitions are percussion powder which provides the initial energy, igniter which ignites the percussion powder, and a delay system that delays the combustion for a period of time. The percussion powder is loaded first, followed by the igniter and then the delay system, and the ammunitions explode by the energy being transferred in the same order. Tamping occurs by combustion-stopping of the igniter or insufficient energy transfer from the igniter to the delay system or the combustion-stopping of the delay system, which are suspected to be caused by low purity of the components, inappropriate mixing ratio, size distribution of particulate components, type of the binder, blending method, hydrolysis by the humidity penetrated during the long term storage, and chemical changes of the components by high temperature. Goal of this study is to find the causes of the combustion-stopping of the igniter and the delay system of the ammunitions after long term storage. In this study, a method was developed for testing of the combustion-stopping, and the size distributions of the particulate components were analyzed with field-flow fractionation (FFF), and then the mechanism of chemical change during long term storage was investigated by thermal analysis (differential scanning calorimetry), XRD (X-ray diffractometry), and XPS (X-ray photoelectron spectroscopy). For the ignition system, M (metal)-O (oxygen) and M-OH peaks were observed at the oxygen's 1s position in the XPS spectrum. It was also found by XRD that $Fe_3O_4$ was produced. Thus it can be concluded that the combustion-stopping is caused by reduction in energy due to oxidation of the igniter.

A Survey of the Status of Nutrition in Rural Korea (농촌(農村) 영양실태(營養實態)에 관(關)한 조사(調査))

  • Lee, Geum-Yeong;Suh, Myung-Sook
    • Journal of Nutrition and Health
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    • v.6 no.1
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    • pp.71-76
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    • 1973
  • 1. This survey is somewhat different from that conducted by Yonsei University, although being in many respects, very similar. We found the average per capita caloric intake to be 7 or 8% of what it should be. Of that caloric intake, 84.5% in the model village here and 82.2% in the compared village Bupyong, by and large depends on cereal grains. Since such grains tend to distend the stomach, the farmers, it seems,should substitute fat for a part of their diet so as to dimish digestive pain and still receive the necessary calories. 2. Protein is the most important nutrient for the development of physical strength and improvement of health, but the average daily intake is only 68.3% of the necessary amount. It is desirable that the ratio of vegetable protein to that of animal be one to three for maintaining one's health. Most of the villager's protein, however, comes from plants: the intake of animal protein, at a level of only 13.6 g, is far below such a one to three ratio. 3. In the model village, 497.6 mg, of inorganic calcium is the daily intake level. In the compared village it is 505.5 mg, making a difference of only 8mg. This, however, is 35% less than the recommended intake. More than 50% of this calcium comes from cereals and other plants. Moreover, plant calcium which has much oxakuc acud us not as nutritional as animal calcium, so their calcium diet is less than it would appear. We must, therefore, make efforts to receive as good nutritional calcium as possible. 4. Among the vitamin group, the daily average intake of vitamin A and vitamin $B_{2}$ are respectively 40% and 32% less than the desired intake, while vitamin $B_{1}$ happens to be taken in sufficient quantities and more niacin is taken than which is even necessary. The intake of vitamin C is much more than the necessary quantity. However, this figure was calculated from uncooked food; if the loss from cooking were to be considered, the real intake might well be a little less. Also, as this survey was carried out in May, some of these results were influenced by the fact that lettuce and spinach are seasonally popular. In conclusion, except for a few nutrients which are in abundance, the normal food intake in a day is, on the whole, less than the average recommended. Furthermore despite the fact that both of these places are model villages in the development of nutrition, it seems that they have not gotten out of such conventional eating habiys as the almost dependancy on cereal grains. Cow's milk, sheep's milk, eggs and so on produced by each farmhouse are not used for their own families but are taken to the market for the purpose of making money. Accordingly, I think from now we must seek to improve, guide and enlighten the farmers as to how to correct their eating habits and implement changes in their lives so that our firm purpose may be achieved.

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