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Effects of Repeated High Ambient Temperature on Performance in Broilers Heat-Conditioned at an Early Age (반복적인 고온환경이 사전고온 적응한 육계의 생산성에 미치는 영향)

  • Hwangbo, Jong;Yang, Young-Rok;Yoon, HyungSook;Kim, Jimin;Park, Byungsung;Choi, Hee Chul;Choi, Yang-Ho
    • Korean Journal of Poultry Science
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    • v.42 no.3
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    • pp.257-265
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    • 2015
  • Heat conditioning at an early age has been known to help chickens cope with heat stress later in life. The present study was conducted to determine the effects of heat conditioning at 5 days of age in broilers repeatedly exposed to high ambient temperature later in life. A total of 256 day-old Arbor Acre boiler chicks were housed in two identical rooms with a 23-h light/1-h dark cycle and provided with feed and water ad libitum. At 5 days of age, the birds in one room were exposed to $37^{\circ}C$ for 24 hours, while those in the other room served as controls. On day 21, half of the birds in each room were moved into the other room so that each room contained both control and heat-conditioned birds. After a 7-day adaptation period, the birds in one room were exposed to high ambient temperature ($21^{\circ}C{\rightarrow}31^{\circ}C$) for 3 days, whereas those in the other room were kept at normal temperature. The same 3-day exposure to high ambient temperature was repeated two weeks later. Hence, there were four treatment groups (CON+CON: control+control; CON+HS: control+high ambient temperature; HC+CON: heat conditioning+control; and HC+HS: heat conditioning+high ambient temperature). Repeated heat stress resulted in decreased feed intake, water intake, body weight gain, and spleen weight (p<0.05) and increased rectal temperature (p<0.05), mortality, and plasma corticosterone concentrations. The relative weight of the spleen was increased in the heat-conditioned group (p<0.05). Plasma biochemicals were also influenced by high temperature. Thus, no beneficial effects of heat conditioning at an early age were detected in broilers repeatedly exposed to high ambient temperature later in life.

A Study on Classification System for Gong-Po-Do Style in Tomb Wall Paintings of Koguryo (고구려 고분벽화 공포도 형식의 분류체계에 관한 연구)

  • Hwang, Se-Ok
    • Korean Journal of Heritage: History & Science
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    • v.49 no.2
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    • pp.20-55
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    • 2016
  • Koguryo's tomb mural paintings in North Korea are our precious cultural heritage which have been designated as UNESCO World Heritage property receiving high praise in the following criterion, i) exceptional creativeness of human being, ii) representative value showing the stage of development in construction history of East-Asia, iii) aesthetic superiority iv) uniqueness of building construction including tombs' ceiling. Mural paintings have been found from almost 100 tombs of the Koguryo dynasty out of 130 which are scattered across Huanren County, Lianoning Province, Ji'an, Jilin Province in China and Pyongyang in North Korea. Especially, most of them are gathered in Pyongyang from 4th and 5th century. Peculiarly, some of them have been constructed before King Jangsu's transfer of the capital to Pyongyang(AD 427). It can be regarded that Pyongyang territory had been under control of Koguryo and to become a new capital in the near future. And dense emergence of such tombs since the capital transfer from Gungnae City to Pyongyang during the reign of Jangsu is linked closely to the construction of tombs for rulers under strengthen royal authority of Jangsu and centralized system of authoritarian rule. Tomb mural paintings describe the owner's figure pictorially based on the truth just as in his living years. General lifestyles of ruling powers and sovereigns can be seen from the wall paintings portraying several buildings with various styles, figures, manners of living, which are considered that the tomb owner had led politically and sociologically in his life. In spite of not enough proofs to approve figure of architectures or "Gong-Po" in wall paintings on the tombs as those of Koguryo, it is persuasive with consideration for painting and decoration inside the tomb like wooden building in real life for the purpose of reenacting and continuing the tomb owner's luxurious life after death. "Du-Gong-Po-Zak" had appeared in company with Koguryo tomb murals and it can be found in most of the murals. And the emergence of substantial "Gong-Po-Do" can be counted more than a century ahead of the figure in murals. It could be a reasonable assumption as regards Koguryo tomb murals time of appearance match up with production period of Gahyungmyunggi(家形明器) and Hwasangseok(畵像石) Hwasangjeon(畵像塼) Design in the Mural Painting of the East-Han(東漢) Ancient Tombs in China. On this study, architectural "Gong-Po"s described in Koguryo tomb murals are categorized largely in "Bi(non)-Po-Zak-kye", "Jun(semi)-Po-Zak-kye", and "Po-Zak-kye" based on presence of "Ju-Du", "Cheom-Cha", and "Cheom-Cha-Sal-Mi" with developmental aspect, and, "Po-zak" is subdivided as "Bi(non)-Cheul-Mok" and "Cheul-Mok" types.

Basic Study on the Building Principles of Structure in Mireuksaji Stone Pagoda (미륵사지서탑 축조의 구조 원리에 관한 기초 연구 6~7세기 전반 목탑과의 비교분석을 중심으로)

  • Cho, Eun Kyung
    • Korean Journal of Heritage: History & Science
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    • v.42 no.2
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    • pp.86-109
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    • 2009
  • Mireuksa Temple was founded during the reign of King Mu of Baekje(AD 600-641). The circumstance of the construction of this temple is documented in "Memorabilia of the Three Kingdoms (Samgukyusa)". The pagoda named stone pagoda at Mireuksaji temple stands outside the main sanctuary of the western area. The south and west sides of the stone pagoda have completely collapsed, leaving only the eastern facade of six of its levels intact. Through the recent discovery of sarira reliquary we can see that the erection of this pagoda was in 639. So owing to accumulation of excavation results about Baekje temple site and vigorous academic exchange, it is possible that architecture of western pagoda at Mireuksaji temple can be understood in connection with the architectural development of wooden pagoda from 6th to early 7th century in East Asia. So this study is on the consideration of building of this pagoda putting first structure of upper part and cross-shaped space in 1st floor. It was considered that the material characteristics as stone could be applied to the temple pagoda architecture of large scale. The results are as follows. First, it had been built in recognition that the outer and inner part of pagoda should be separated. As it is the expression of structural system in temple pagoda architecture of large scale at that time. In pagoda there was a self-erected structure and the members of outer part of it were constructed additionally. Second, in Mireuksaji stone pagoda there is central column with stones. With inner part of pagoda it can be regarded as mixed structural system that constitutes central contral column and inner structural part. And it could be a kind of middle step to more developed structure of whole as wooden pagodas in Japan. Third, as the sarira reliquary was in central column on the first floor, the cross-shaped space could be made. The formation of this space was so on the natural meaning of sarira that the concept as memorial service of graves could be apllied to the pagoda. The style of tomb in Baekje was expressed to the space of 1st floor in pagoda where Sarira had been mstalled. That was not only effective presentation of symbolic space but also easier method in the use of same material.

Studies on the Nitrogenous Utilization and Basal Metabolism of Korean Native Goat (한국(韓國) 재래산양(在來山羊)의 질소대사(窒素代謝) 및 기초대사량(基礎代謝量)에 관(關)한 연구(硏究))

  • Oh, Hong Rock
    • Korean Journal of Agricultural Science
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    • v.9 no.2
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    • pp.546-555
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    • 1982
  • To evaluate the digestibility and absorbability of proteins, and the rates of energy and nitrogen(N) metabolism of the Korean native goats, studies were carried out with open type respiration apparatus based on the nitrogen-carbon method. The results on the nitrogen retention and the metabolic rate of energy, which was obtained with one male (10-month-old) and one female (24-month-old) goats, both weighing ${\simeq}20kg$, are summarized as follows. 1. When the goats were fed ad libitum the medium quality orchard grass hay, they consumed hay about 0.66 to 0.92% of body weight per day. The hay intake was remained the same even when high quality hay was provided. This amount of hay intake was relatively lower than that of dairy goat and sheep. It was believed to be partly due to the change in feeding enviroment. When fed with hay and soybean meal together, the goats ate hay about 1.06% and soybean meal about 0.60% of body weight, corresponding to 1.66% of body weight as fed basis. 2. The $CO_2$ gas produced from the goat in the open type respiration chamber and absorbed with KOH solution was estimated to be 99~117g/day. The difference in feed intake did not influence the $CO_2$ production; however, these seems to be a linea relationship between body weight and $CO_2$ production. 3. When fed orchard grass hay only, the goats showed protein digestibility of 24~41%. The protein digestibility incresed to 58.2% when fed hay and soybean meal together. A negative nitrogen balance(-0.16g N/day) was observed with goats fed 11.53g N originated from 212g hay and 150g soybean meal. Converting that nitrogen ingested to a crude protein, the amount of crude protein intake by the goats per day was 77.9g compared to 40~45g N known to be required in a day by goat weighing 20kg, indicating that the extra protein ingested was metabolized to provide energy. 4. When the male and female goats comsumed 624 kcal gross energy and 824 kcal gross energy by consuming 158g and 213g of hay, respectively, the digestible energy intake was calculated to be 260kcal for the male and 199kcal for the female goat. The daily heat production of male and female goats were 338kcal and 334kcal, respectively, when fed hay only. However, the female goat fed 212g hay and 150g soybean meal produced about 591kcal per day. Consequently, the energy requirment of the Korean native goats weighing ${\simeq}20kg$ was concluded to be $${\geq_-}$$600kcal net energy per day. 5. The fasting heat product ion of a male goat weighing 27.7kg was 412kcal per day when fasted for 2~3 days. When fasted for 3~4 days, the value decresed to 240kcal. The enviromental temperatures during the expreimental period were ranged from 19 to $34.5^{\circ}C$. The goats seemed to be panting when the chamber temperature rose to $32^{\circ}C$ or above. 6. When fed low levels of dietary protein, serum protein levels of the goats were decresed slightly ($${\leq_-}$$10%); however, urea content in the serum was observed to decrese to a great extent (3X).

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The Profile of Milling Plants in Korea (우리나라 양곡가공공장의 현황분석)

  • 정창주;금동혁;강화석
    • Journal of Biosystems Engineering
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    • v.3 no.1
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    • pp.47-63
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    • 1978
  • This study was conducted to obtain a basic information necessary to assess present rice milling technology in Korea The profiles for milling plants was analyzed by survey work.For the private custom-work mills, which process about 80 percent of domestic rice consumption ,their actual milling test for the identical samples as used for filed mills was conducted. Two rice varieties Japonica and Tongil-type were associated with the experiments. The results are summarized as follows: 1. Analyses for private custom-work mills showed their general aspects as; about 91 percent of the mills belonged to an individual owner ship ; more than 93 percent of the mills was established earlier than 1950 ; about 80 percent of the mills was powered with electric motor; mills having less than two employees were about 75 percent; about 45 percent of the mills provided for warehouse in storing customers cereal grains. 2. The polishers installed in 1,255mills within the surveyed area (7 counties) have been supplied by 44 different domestic manufacturers ;in but about 60 percent of which was supplied by 6major manufacturers. The polishers could be classified into two categories in terms of principles of their polishing actions ;jet-pearler and friction types. About 51 percent of the mills was equipped with the former which has been recognized as giving greater milling recovery than the friction types. 3. Reason for owners of private mills to supplement new machines was due mainly to pgrading their mills to meet the requirements that established by the Government. However, about 60 percent of the mill owners intended to replace with new pearler by their own needs to meet with new high yielding varieties. 4. Processing systems of each previate rice mills surveyed could be classified into three categories, depending upon whether the systems posessed such components as precleaner and paddy separator or not. Only 36.7 percent of mills was installed with both precleanr ad paddy seperrator, 5.0 percent of mills did have neither percleaner nor paddy seperator, and rest of them equipped only one of the two. Hence,it is needed for about 63% of rice miils to be supplemented with these basic facilities to meet with the requirements for the standaized system. 5. Actual milling capacity measured at each field rice mills was shown a wide variation, having range from about 190 to 1,210 kg/hr. The percentages of mills classified according to daily milling capacity based on this hourly capacity were 24.3% for the capacity less than 3 M/T a day; 20.0% for 3-4 M/T; 15.6% for 4-5 M/T; 6.7% for 5-6 M/T; 22.3% for 6-7 M/T; and 11.0% for more than 7 M/T a day. 6. Actual amount of rice processed was about 310 M/T a year in average. About 42% of total milled rice was processed during October to Decembear, which formed a peak demand period for rice mills. The amount of rice milled during January to May was relatively small, but it had still a large amount compared to that during June to September. 7. Utilization rate of milling facility, i. e., percentage of the actual amount of milled rice to the capacity of rice mills, was about 18% on the year round average, about 41% in the peak demand season, and about 10% during June to September. Average number of operating days for mills surveyed was about 250 days a year, and about 21 days a month. 8. Moisture contents of paddy at the time of field mill tests were ranged 14.5% to 19.5% for both Japonica and Tong-i] varieties, majority of paddy grains having moisture level much higher than 1530. To aviod potential reduction of milling recovery while milling and deterioration of milled rice while storage due to these high grain mJisture contents, it may be very important for farmers holding rice to dry by an artificial drying method. 9. Milling recovery of JapJnica varieties in rice mills was 75.0% in average and it was widely ranged from 69.0% to 78.0 % according to mills. Potential increase in milJing recovery of Japonica variety with improvement of mill facilities was estimated to about 1.9%. On the other hand, milling recovery of Tong-il varieties in the field mill tests was 69.8% in average and it ranged from 62% to 77 %, which is much wider than that of Japonica varieties. It is noticed that the average milling recovery of Tong-il variety of 69.8% was much less than that of the Japonica-type. It was estimated th3.t up to about 5.0% of milling recovery for Tong-il variety could be improved by improving the present lo'.ver graded milling technology. 10. Head rice recoveries, as a factor of representing the quality of commercial goods, of Japonica and Tong-il varieties were 65.9% and 53.8% in average, and they were widely ranged from 52% to 73% and from 44% to 65% , respectively. It was assessed that head rice recovery of Japonica varieties can be improved up 3.3% and that of Tong-il varieties by 7.0% by improving mill components and systems.

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Hypoglycemic Effects of Pills Made of Mulberry Leaves and Silkworm Powder in Streptozotocin-Induced Diabetic Rats (뽕잎과 누에가루 혼합환의 Streptozotocin유발 당뇨쥐에서의 혈당강하 효과)

  • Jang, Mi-Jin;Rhee, Soon-Jae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.10
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    • pp.1611-1617
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    • 2004
  • This study was carried out to examine the effects of pills made of mulberry leaves and silkworm powder on lowering blood glucose level. Experimental animals were Sprague-Dawley male rat weighing 100$\pm$10 g and pills were supplemented with 0.4% (4 g/kg) diet. Experimental groups were assigned to diabetic group (DM group) and pill supplemented groups. Pill supplemented groups were classified 100% mulberry leaves (M group), mixing 25% silkworm powder to mulberry leaves (25SM group), mixing 50% silkworm powder to mulberry leaves (50SM group), mixing 70% silkworm powder to mulberry leaves (75SM group) and 100% silkworm powder (100S group). Experimental diets and water fed ad libitum, and streptozotocin was injected to induce diabetic state after 3rd weeks and sacrificed on the 9th day. The contents of 1-deoxynojirimycin(DNJ) were increased with adding the silkworm powder. The contents of GABA and rutin were increased with adding the mulberry leaves. In vitro, intestinal mucosa $\alpha$-glucosidase inhibitory activities were significantly increased in pills which mixed with silkworm powder by 50%. Blood glucose levels were high in groups which mixed with silkworm powder by 50% compared to DM group. Intestinal mucosa maltase activity in proximal part was significantly reduced in pill supplemented group compared to DM group and pill supplemented groups were no significant difference. Enzyme activity in middle part was no significant difference in experimental groups. Enzyme activity in distal part was decreased in pill supplemented groups, especially in 50SM, 75SM and 100S groups were significantly reduced compared to DM group. Sucrase and lactase activities in pill supplemented groups were significantly reduced at proximal part, and there was no significant difference in middle and distal parts. In conclusion, pills made of mulberry leaves and silkworm powder increased the $\alpha$-glucosidase inhibitory activity in vitro and reduced the blood glucose levels by controlling the disaccharidase activities of intestinal proximal part in STZ-induced diabetic rat. The synergistic effect was the highest when mulberry leaves was mixed with silkworm powder by the ratio of 50 : 50.

A Study on the Influence of Conflict on the Performance and Validity of Organization (갈등이 조직성과 및 조직 유효성에 미치는 영향에 대한 연구)

  • 기호익
    • The Journal of Information Technology
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    • v.1 no.2
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    • pp.81-102
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    • 1998
  • It is common description that modern society is In the era of limitless competition. In order to challenge the change of economy and its management at home and abroad, organization should be changed anew, and in this case, there accompanies conflict or trouble whether the subject of change wants it or not. Therefore, according to change, we should concern with settlement of small troubles as well as big ones, and by managing the conflict or trouble productively and originally, it should be utilized as new fatality and chance to develop something in organization. In the system organized by people, there exist various conflicts in accordance with the target and want of the system, therefore giving no freedom to each Individual member of the system, and this is an unavoidable tate in consideration of the modem society where the survival of mankind and human systems should be guaranteed. Therefore, it determines the coordinates of success of any of organizations to manage conflict or trouble well, and so, when decreasing or increasing conflicts so that the organization exerts its full influence, it is note worthy that conflict itself should be rationally and efficiently managed. In a view point of the theory of organization and its behavior, relating job satisfaction with the performance and validity of organization, the influence of individual conflict is so great on the rate of job transfer within an organization or nonattendance, even on the productivity of the organization. So, the manager to cope with conflict within an organization should devise following three plans to manage conflict for job satisfaction and conflict settlement. In conclusion, it is suggested that in order to manage conflict within an organization well, some plans to control conflict should be well utilized while giving more efforts to improving management of individual conflict, job satisfaction, validity of organization, productivity, etc and all the members of organization should remember that the Issue of conflict within an organization be recognized ad an opportunity of new development and a way to settle a trouble within an organization, and a direction of conflict management should be suggested so that new innovation ca be created.

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Effect of Dietary Crude Protein and Amino Acid Contents on Growth Performance and Carcass Characteristics in Korean Native Ducks (사료의 조단백질 및 아미노산 함량이 토종오리의 성장과 도체 특성에 미치는 영향)

  • Kwon, Hyung Joo;Choo, Yun Kyung;Oh, Sung Taek;Kim, Hak Kyu;Kang, Chang Won;An, Byoung Ki
    • Korean Journal of Poultry Science
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    • v.40 no.4
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    • pp.351-359
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    • 2013
  • This study was undertaken to assess dietary crude protein (CP) and amino acid (AA) concentrations for growth performance and carcass characteristics in Korean native ducks. In a $2{\times}3$ factorial arrangement, 1-d-old Korean native male ducks were allotted to 6 dietary treatments in a completely randomized design. Experimental diets contained 23 or 21% CP with 1.31/1.09, 1.21/1.00, 1.11/0.91 and 1.11/0.91, 1.02/0.83, 0.92/0.75 AA (Lysine/Total sulfur amino acid, Lysine/TSAA), respectively, from 0 to 3 wk of age. From 4 to 8 wk of age, experimental diets had 19 or 17% of diet; each contained 1.00/0.79, 0.94/0.75, 0.88/0.71 and 0.88/0.71, 0.82/0.67, 0.76/0.63 AA (Lysine/TSAA), respectively. Each dietary treatment has 6 replicates and feed and water were provided ad libitum. Body weight (BW), feed intake and uniformity were measured at 3 wk and 8 wk and carcass characteristics were evaluated at 8 wk of age. As CP increased from 21 to 23%, the BW and BW gain significantly increased (P<0.05) during 0 to 3 wk of age. From 4 to 8 wk of age, BW, feed intake, BW gain, feed conversion rations (FCR) and uniformity were not different (P>0.05) between treatments. Carcass yield and relative weights of liver, spleen, right breast and leg per 100 of BW were not different (P>0.05) between treatments. The meat color, shear force value, cooking loss and pH were not affected by dietary treatments (P<0.05). Korean native ducks require relatively low levels of dietary CP and AA for late growth and carcass yield due to low daily weight gain. This suggests the possible differences in CP and AA needs between Korean native ducks and commercial breeds from foreign breeding companies, especially late growth stage.

Basic Studies on the Development of Diet for the Treatment of Obesity II. Comparison of the Inhibitory Effect of Algae and Crude Drug Components on Obesity (비만치료식 개발을 위한 기초연구 2. 조류와 생약성분의 비만억제작용 비교)

  • CHOI Jin-Ho;CHOI Jae-Sue;BYUN Dae-Seok;YANG Dal-Sun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.19 no.5
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    • pp.485-492
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    • 1986
  • This study was designed to compare the inhibitory effects of algae components such as alginic acid and chlorella extract with the red ginseng saponin and garlic components such as alliin and scordinin on obesity. These components supplemented to basic diet were fed ad libitum to Sprague Dawley rats for 4 weeks, and the inhibitory effects on obesity were evaluated by measuring body weight gain and feed efficiency, the contents of glucose and cholesterol in serum, lipase activity in serum, lipid contents in liver and adipose tissue around epididymis and ovarium, and Lee index, etc. Among the inhibitory effects of these components on obesity, Na-alginate($71\%$) was the most effective (p<0.01), and the others were effective (p<0.001) in the order of scordinin ($76\%$) = chlorella ($76\%$)> alliin ($86\%$) for body weight gain, but Na-alginate ($68\%$) was the most effective, followed by alliin ($79\%$) for feed efficiency (p<0.001). In the inhibitory effects on lipid accumultion in liver and adipose tissue, Na-alginate ($84\%$) among these components was the most effective (p<0.001) in liver, but Na-alginate ($54\%$) was the most effective (p<0.001), followed by alliin ($64\%$), and followed by scordinin ($66\%$) in adipose tissues around epididymis and ovarium (p<0.001). The inhibitory effect on obesity evaluated by Lee index was observed in Na-alginate ($91\%$) only (0.001). The decreasing effects of lipid content in liver by these components were effective in the order of alliin ($40\%$)> saponin ($58\%$)> Na-alginate($62\%$)> chlorella ($64\%$)> scordinin ($74\%$) (p<0.001). G lucose contents in serum were significantly decreased in cases of Na-alginate ($67\%$), saponin ($73\%$), scordinin ($74\%$) and alliin ($83\%$), and cholesterol contents in serum were significantly decreased in cases of Na-alginate ($82\%$), chlorella ($86\%$) and saponin ($89\%$) (p<0.001). The increasing effect of lipase activity in serum was effective in cases of Na-alginate ($109\%$) and saponin ($104\%$), while garlic components such as alliin and scordinin, and chlorella were decreased. It is proved that the inhibitory effect of alginic acid which is the major component of brown algae on obesity was more effective than those of ginseng and garlic components such as saponin, alliin and scordinin.

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INFLUENCE OF A SODIUM HYPOCHLORITE GEL ON MICROLEAKAGE OF COMPOSITE RESIN RESTORATIONS (차아염소산 나트륨의 사용이 복합레진 수복물의 미세누출에 미치는 영향)

  • Yang, Kye-Sik;Kim, Dae-Eop;Lee, Kwang-Hee;Jeong, Young-Nam
    • Journal of the korean academy of Pediatric Dentistry
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    • v.30 no.1
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    • pp.54-60
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    • 2003
  • This study evaluated the influence of chemomechanical caries removal agent $Carisolv^{TM}$(MediTeam, Sweden) for composite resin adhesion to sound human permanent and primary dentin. The buccal/labial surfaces of 80 permanent molars and 80 primary incisors were used. Four types of adhesives and one composite resin were used; AQ Bond(Sun Medical, Japan), Clearfil SE Bond(Kuraray, Japan), Single Bond(3M, USA), Scotchbond Multi-Purpose(3M, USA) and Z100(3M, USA). One drop of $Carisolv^{TM}$(MediTeam, Sweden) was pretreated on the dentin for 0 second(control) and 60 seconds. The specimens were thermocycled for 1,000 times in baths kept 5 degrees C and 55 degrees C with a 30 seconds dwell time. Shear bond strengths were tested and the data was statistically analyzed using one-way ANOVA with subsequent post hoc Scheffe test at p<0.05. $Carisolv^{TM}$ treatment significantly decreased the shear bond strength. Shear bond strength of permanent dentin was significantly higher than that of primary dentin. Clearfil SE Bond treatment groups showed the highest shear bond strength and AQ Bond treatment groups showed the lowest shear bond strength.

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