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Shear bond strength of dentin bonding agents cured with a plasma arc curing light (전단접착강도와 관련된 Plasma Arc Curing Light의 중합효율평가)

  • Kwon, Young-Chul;Kim, Sun-Young;Chung, Sae-Joon;Han, Young-Chul;Lee, In-Bog;Son, Ho-Hyun;Um, Chung-Moon;Cho, Byeong-Hoon
    • Proceedings of the KACD Conference
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    • 2008.05a
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    • pp.213-223
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    • 2008
  • The objective of this study was to compare dentin shear bond strength (DSBS) of dentin bonding agents (DBAs) cured with a plasma arc (PAC) light curing unit (LCU) and those cured with a light emitting diode (LED) LCU. Optical properties were also analyzed for Elipar freelight 2 (3M ESPE); LED LCU, Apollo 95E (DMT Systems); PAC LCU and VIP Junior (Bisco); Halogen LCU. The DBAs used for DSBS test were Scotchbond Multipurpose (3M ESPE), Singlebond 2 (3M ESPE) and Clearfil SE Bond (Kuraray). After DSBS testing, fractured specimens were analyzed for failure modes with SEM. The total irradiance and irradiance between 450 nm and 490 nm of the LCUs were different. LED LCU showed narrow spectral distribution around its peak at 462 nm whereas PAC and Halogen LCU showed a broad spectrum. There were no significant differences in mean shear bond strength among different LCUs (P > 0.05) but were significant differences among different DBAs (P < 0.001).

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Shear bond strength of dentin bonding agents cured with a plasma arc curing light (전단접착강도와 관련된 Plasma Arc Curing Light의 중합효율평가)

  • Kwon, Young-Chul;Kim, Sun-Young;Chung, Sae-Joon;Han, Young-Chul;Lee, In-Bog;Son, Ho-Hyun;Um, Chung-Moon;Cho, Byeong-Hoon
    • Restorative Dentistry and Endodontics
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    • v.33 no.3
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    • pp.213-223
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    • 2008
  • The objective of this study was to compare dentin shear bond strength (DSBS) of dentin bonding agents (DBAs) cured with a plasma arc (PAC) light curing unit (LCU) and those cured with a light emitting diode (LED) LCU. Optical properties were also analyzed for Elipar freelight 2 (3M ESPE); LED LCU, Apollo 95E (DMT Systems); PAC LCU and VIP Junior (Bisco); Halogen LCU. The DBAs used for DSBS test were Scotchbond Multipurpose (3M ESPE), Singlebond 2 (3M ESPE) and Clearfil SE Bond (Kuraray). After DSBS testing, fractured specimens were analyzed for failure modes with SEM. The total irradiance and irradiance between 450 nm and 490 nm of the LCUs were different. LED LCU showed narrow spectral distribution around its peak at 462 nm whereas PAC and Halogen LCU showed a broad spectrum. There were no significant differences in mean shear bond strength among different LCUs (P > 0.05) but were significant differences among different DBAs (P < 0.001)

Fenugreek seeds reduce aluminum toxicity associated with renal failure in rats

  • Belaid-Nouira, Yosra;Bakhta, Hayfa;Haouas, Zohra;Flehi-Slim, Imen;Cheikh, Hassen Ben
    • Nutrition Research and Practice
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    • v.7 no.6
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    • pp.466-474
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    • 2013
  • Despite the reports on safety concerns regarding the relationship between aluminum salts and neurological and bone disease, many countries continue to use aluminum as phosphate binders among patients with renal failure. In search for a diet supplement that could reduce aluminum toxicity related to renal failure, we carried out this prospective animal study in which the fenugreek seeds were assessed for their effects on rats nephrotoxicity induced by aluminum chloride ($AlCl_3$). Oral $AlCl_3$ administration during 5 months (500 mg/kg bw i.g for one month then 1600 ppm via drinking water) led to plasma biochemical changes, an inhibition of alkaline phosphatase (ALP), a decrease of total antioxidant status (TAS), and an induction of lipid peroxidation (LPO) in the blood and brain, in addition to kidney atrophy and morphological alterations at the level of Bowman's capsule, the glomerulus and different sorts of tubules, reminiscent of some known kidney disease. The treatment with the whole fenugreek seed powder (FSP) (5% in the diet) during the last 2 months showed its effectiveness in restoring normal plasma values of urea, creatinine, ALP and glucose, as well as re-increasing the TAS, inhibiting LPO and alleviating histopathological changes in the injured kidneys. This study highlights the induced nephrotoxicicity, as well as the related toxicity in the brain and bone, by chronic oral ingestion of the aluminum salts. However, the maintenance of a diet supplemented with fenugreek seeds could offer protection for the kidney, bone and brain, at the same time.

Effect of picloram and 2,4-D on plant regeneration from mature and immature embryos of moroccan durum wheat varieties

  • Ahansal, Khadija;Aadel, Hanane;Udupa, Sripada Mahabala;Gaboun, Fatima;Abdelwahd, Rabha;Ibriz, Mohammed;Iraqi, Driss
    • Journal of Plant Biotechnology
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    • v.49 no.2
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    • pp.131-138
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    • 2022
  • An efficient genetic transformation protocol is a fundamental requirement for high regeneration capacity from cultivated durum wheat (Triticum durum) varieties. In this study, wereportedtheeffectsoftwoauxins,2,4-dichlorophenoxyaceticacid(2,4-D)and4-amino-3,5,6-trichloropicoli nicacid(picloram), at a concentration of 2 mg/Laloneandincombination on the embryogenic callus and plantlet regeneration of four durum wheat varieties (Amria, Chaoui, Marouane, and Tomouh) using mature embryos (MEs) and immature embryos (ImEs). Significanteffectsofvariety,culturemedium(theauxinused),andvariety-mediuminteraction were observed on the callus weight and plantlet regeneration of both MR and ImE explants. The medium used for callus induction significantly affected plantlet regeneration (p < 0.001). Comparedto2,4-D, picloram led to a higher plantlet regeneration rate in both ME and ImE explants (19.8% and 40.86%, respectively). Plantlet regeneration also varied significantly depending on the variety and medium used. PicloramledtohighplantletregenerationofbothME and ImE explants in all varieties except Tomouh, which showed high plantlet regeneration of ME explants in 2,4-D. A comparison of ME and ImE responses indicated that ImEs are the best explants for high plantlet regeneration in durum wheat. Ourfindingssuggestthatpicloramisthebestauxin and should be used instead of 2,4-D due to its positive effect on increasing plant regeneration of durum wheat ME and ImE explants.

The Analysis of Contents on Education for Sustainable Development(ESD) in Middle School Home Economics Textbooks : Focused on the Units of 'Adolescence Consumption Life' (지속가능발전교육(ESD)을 위한 중학교 기술·가정 교과서 가정생활 영역 분석 연구 - 청소년의 소비 생활 단원을 중심으로 -)

  • Ju, Sueun
    • Journal of Korean Home Economics Education Association
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    • v.28 no.2
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    • pp.79-93
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    • 2016
  • This study analyzes the middle school Home Economics textbook's 'Adolescence consumption life' unit using framework of Education for Sustainable Development(ESD) to examine correlation with the current Home Economics ESD, and aims to provide the base data for the composition of the educational curriculum that can help the students cultivate the capability for leading sustainable life from the future oriented perspective and for the selection of educational contents. This study analyzes the 'Adolescence consumption life' unit in the Home Economics textbook of the 12 type revised curriculum of 2009. As for the analysis method, Romey's content analysis method is used to carry out in-depth analysis of the ESD content elements. The analysis demonstrates the following. First, content elements extracted commonly from the 'Adolescence consumption life' unit are analyzed with the ESD's criteria of analysis (environment, economic and social domain), which led to the composition with the sub content elements following 23 related topics. Secondly, content elements of 12 types of Home Economics textbook's 'Adolescence consumption life' unit used in middle school are analyzed in three domains, which led to social domain (68%), economic domain (58%) and environmental domain (40%) in the order mentioned. This focused on the role of the Adolescent-consumer on the active consumer that is presented in the 2009 revised educational curriculum, and it is possible to see that this is very closely related to the right to organize and to be active in terms of the human safety, consumption culture, social interest and group.

Desulfurization efficiency in photobioreactors dependent on the irradiation type of light sources (광생물반응기내 광조사 유형별 탈황 효율)

  • An, Jin Young;Kim, Byung Woo
    • Clean Technology
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    • v.6 no.1
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    • pp.71-78
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    • 2000
  • Removal rates of hydrogen sulfide were investigated to known effects of several light sources with external and internal irradiation on the desulfurization using C. thiosulfatophilum. In the case of internal illumination system, optical-fiber photobioreactor was applied to increase the light availability. Furthermore, sunlight was used as the main light energy in the daytime and metal-halide lamp was applied as an additional light energy at night. Light energy of 99% was saved by the application of the LED's array in comparison with the incandescent light source. $H_2S$ removal rates at 5,000 lux in a 4-L photobioreactor were shown as 0.040, 0.138, 0.136, and 0.134 (${\mu}mol$ $H_2S/min$)/(mg protein/L), respectively, in the following order of light sources, when several light sources such as fluorescent, energy-saving, incandescent, halogen lamp, and filtered light at 460 nm were applied. Removal rate per unit cell concentration with the internal light diffused optical-fibers increased about 1 six times as much as that with the external light sources. Removal rate per unit cell concentration, using sunlight in the daytime and a metal-halide lamp at night, was 0.41 less than 0.869 (${\mu}mol$ $H_2S/min$)/(mg protein/L) using a 400 W metal-halide lamp day and night, since the automatic sunlight collection system can transmit the light intensity as only 10% of that with a metal-halide lamp.

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Fabrication of a Nano-Wire Grid Polarizer for Brightness Enhancement in TFT-LCD Display (TFT-LCD용 휘도 성능을 향상시키는 나노 와이어 그리드 편광 필름의 제작)

  • Huh, Jong-Wook;Nam, Su-Yong
    • Journal of the Korean Graphic Arts Communication Society
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    • v.29 no.3
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    • pp.105-124
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    • 2011
  • TFT-LCD consists of LCD panel on the top, circuit unit on the side and BLU on the bottom. The recent development issues of BLU-dependent TFT-LCD have been power consumption minimization, slimmerization and size maximization. As a result of this trend, LED is adopted as BLU instead of CCFL to increase brightness and to reduce thickness. In liquid crystal displays, the light efficiency is below 10% due to the loss of light in the path from a light source to an LCD panel and presence of absorptive polarizer. This low efficiency results in low brightness and high power consumption. One way to circumvent this situation is to use a reflective polarizer between backlight units and LCD panels. Since a nano-wire grid polarizer has been known as a reflective polarizer, an idea was proposed that it can be used for the enhancement of the brightness of LCD. The use of reflective polarizing film is increasing as edge type LED TV and 3D TV markets are growing. This study has been carried out to fabrication of the nano-wire grid polarizer(NWGP) and investigated the brightness enhancement of LCD through polarization recycling by placing a NWGP between an c and a backlight unit. NWGPs with a pitch of 200nm were fabricated using laser interference lithography and aluminum sputtering and wet etching. And The NWGP fabrication process was using by the UV imprinting and was applied to plastic PET film. In this case, the brightness of an LCD with NWGPs was 1.21 times higher than that without NWGPs due to polarization recycling.

The Effects of Using Cartoon at Finishing Stage of Class on Scientific Attitude and Academic Achievement (학습정리 단계에서 만화자료를 활용한 수업이 과학적 태도 및 학업성취도에 미치는 영향)

  • Lee, Hyeong-Cheol;Lee, Sun-Young
    • Journal of the Korean Society of Earth Science Education
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    • v.3 no.3
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    • pp.184-190
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    • 2010
  • This study is to verify the effects of classes at a finishing stage using cartoons depicting certain science textbook units on scientific attitudes and academic achievements of students, compared to those of classes using experiment and observation oriented textbooks. Participants of this study were 56 fifth graders at B Elementary School in Busan, and cartoon textbooks were developed based on 'Unit 1. Mirror & Lens' and 'Unit 3. Temperature & Wind' from a science textbook for the 1st semester, the year 5 to conduct cartoon led lessons just before ending a class till the 10th lesson, for the period of 4 weeks. The result of this study can be summarized as follows: Firstly, scientific attitudes improved better from the cartoon based lesson of a final stage than from the experiment and observation method, and especially more effective in lower groups among all other academic achievement levels as well as in male students. Secondly, academic achievements scored higher when cartoons were used in lessons than when the experiment and observation type was used, with higher groups of academic achievement levels working better, despite no significant gap existing between two genders. Thirdly, the memory transfer and sustenance of lessons were more effective in finishing class stage with cartoon studies than with experiment and observation one, and among all levels and both sexes, higher academic groups and male pupils exceeded. Fourthly, when questioned about their opinions on a cartoon led lesson for a final stage, 65% of those participants responded positively, while higher groups preferred more than lower groups. responded positively, while higher groups preferred more than lower groups.

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Development of Standing and Moving Human Body Sensing Module Using a Chopper of Shutter Method (셔터방식의 쵸퍼를 이용한 정지 및 이동인체 감지 모듈 개발)

  • Cha, Hyeong-Woo;Lee, Won-Ho
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.2
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    • pp.109-116
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    • 2016
  • Sensing module of standing and moving human body using shutter method was developed. The module consists of Fresnel lens, pyroelectric infrared (PIR) sensor, interface circuit of the PIR, micro control unit(MCU), and alarm light emitting diode(LED). The principle for standing human body is chopping the thermal of human body using camera shutter. The human sensing signal in MCU by algorithm of interrupt function is detected. By unifying an apparatus and print circuit board(PCB), the developed module can be replaced as commercial moving human body detector. Experiment results show that sensing distance is about 7.0m and sensing angles is about $110^{\circ}$ at room temperature. In these condition, sending ratio was 100% and the power dissipation of the module was 100mW.

The effect of different colored light emitting diode illumination on egg laying performance, egg qualities, blood hormone levels and behavior patterns in Brown Tsaiya duck

  • Su, Chin-Hui;Cheng, Chih-Hsiang;Lin, Jung-Hsin;Liu, Hsiu-Chou;Yu, Yen-Ting;Lin, Chai-Ching;Chen, Wei-Jung
    • Animal Bioscience
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    • v.34 no.11
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    • pp.1870-1878
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    • 2021
  • Objective: The objective of this experiment was to investigate the effects of different colors produced by light emitting diode (LED) on Brown Tsaiya ducks. Methods: A total of 144 female Brown Tsaiya ducks were randomly allocated into three individual cage rearing chambers with different LED illumination colors as treatments. Three different treatments were: i) white color, ii) blue color, and iii) red color. The experiment periods were from ducks 21 to 49 weeks of age, determined traits included i) egg laying performance, ii) feed intake, iii) egg shell breaking strength, iv) egg shell thickness, v) egg Haugh unit, vi) egg weight, vii) serum Estradiol and Progesterone concentration, and viii) behavior pattern. Results: The results indicated that when compared with white and blue color, red color could stimulate ducks sexual maturation and raised the egg laying performance. The red light group was also observed to have the highest feed intake among three treatments. The blue treatment had the lowest egg shell breaking strength and the highest egg weight among three treatments, nevertheless, no significant difference was observed among three treatments on egg shell thickness and egg Haugh unit. The red light group had higher serum estradiol concentration than the white and blue groups, but no significant difference among treatments on the serum Progesterone concentration was found. The results of behavior pattern indicated that red light group showed more feeding and less resting behavior compared to the blue light group. Conclusion: We found a potential of applying red light illumination in the indoor laying duck raising system with positive results on egg laying performance and acceptable egg weight, equivalent egg qualities compared to white and blue light.