• Title/Summary/Keyword: retardation test

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Liriopis Tuber improves stress-induced memorial impairments in rats (구속 스트레스로 유발된 기억 손상에 대한 맥문동(麥門冬)의 신경보호 효능)

  • Kang, Young-Gun;Lee, Tae-Hee
    • The Korea Journal of Herbology
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    • v.21 no.2
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    • pp.63-75
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    • 2006
  • Objectives : We investigated the effects of Liriopis Tuber on the nervous protection. Methods : We measured the reaction behavior with EPM(Elevated Plus Maxe) and MWM(Morris Water Maze) after applying restraint stress to rats. Also, the degrees of AchE generation were measured with immunohistochemical method in the regions of hippocampus, and the degree of TH generation in the regions of VTA and LC, respectively. Results : 1. As the results of measuring how long EPM which reflects anxiety reaction stayed in the open arm, there was the trend which can suppress anxiety reaction in the MMD+stress group(Liriopis Tuber+stress) but no statistical significance. The counting results how many EPM passed between opened and closed arm showed suppression trend against a physical activity in the saline+stress group but there was no statistical significance. 2. According to the result of MWM, the saline+stress group showed the learning retardation which means increased time arriving at goal compared to ti1e normal group at the second and third day of measurement. On the contrary, a learning retardation was significantly decreased in the MMD+stress group. Among the probe trial test a memory loss occurred in the saline+stress group, meanwhile memory ability was notably increased in the saline-stress group. 3. The degree of TH generation was investigated at the VTA and LC respectively after test animals treated with drug. In the saline+stress group, TH-immunoreactive cells were significantly increased, and these stress-induced TH increases were suppressed in the saline+stress group at the VTA region. However, the saline+stress group did not show any significant difference. 4. the degree of AchE generation was investigated at the CA3 of hippocampus. The saline+stress group showed that AchE-immunoreactive cells were significantly decreased. Those stress-induced reductions of AchE cells were meaningfully recovered in the saline+stress group. Although the cells showed recovery trend in the region of CA1 of hippocampus, statistical significance was not observed. Conclusion : The results of our study indicate that Liriopis Tuber can improve spatial memory ability of rats applied a restraint stress. This improvement of the spatial memory ability is considered to have an efficacy of nervous protection that Liriopis Tuber suppresses the generation of AchE in the hippocampus region and enhances the generation of TH in the VTA.

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Performance of Geogrids for Retarding Reflection Crack of Asphalt Overlay Pavement (아스팔트 덧씌우기의 반사균열 지연을 위한 지오그리드의 적용성 연구)

  • Kim, Kwang-Woo;Doh, Young-Soo;Kim, Bun-Chang;Lee, Moon-Sup
    • International Journal of Highway Engineering
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    • v.7 no.2 s.24
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    • pp.1-12
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    • 2005
  • This study was conducted to evaluate effect of geogrid and fabric, which are used underneath the overlaid asphalt pavement for retarding reflection cracking by simulated laboratory test. In this study, an interlayer at the interface between old concrete pavement surface and overlaid asphalt mixture, and polymer-modifier were used as an effort of retarding reflection crack initiation and for strengthening mixture. Five products were used in preparation of asphalt concrete beam specimen which was tack coated on top of jointed concrete block. Simulated Mode I and II fracture test were conducted under wheel loading and results were compared among those products. From the test results, several material and reinforcement combinations were observed to have a significant retardation effect against reflection cracking. The most effectively strengthened pavement against reflection cracking was found to be the LDPE-modifier asphalt mixture with a grid reinforcement at the bottom.

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Separation of $CO_2$ and $N_2$ with a NaY Zeolite Membrane under Various Permeation Test Conditions

  • Cho, Churl-Hee;Yeo, Jeong-Gu;Ahn, Young-Soo;Han, Moon-Hee;Hyun, Sang-Hoon
    • Korean Membrane Journal
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    • v.8 no.1
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    • pp.21-30
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    • 2006
  • A faujasite NaY zeolite membrane was prepared on a tubular ${\alpha}-Al_2O_3$ support by the secondary growth process, and effects of permeation test conditions on the $CO_2/N_2$ separation were investigated. A NaY zeolite membrane with good $CO_2/N_2$ separation was successfully synthesized by using the hydrothermal solution ($Al_2O_3:SiO_2:Na_2O:H_2O$ = 1:6:14:840 in a molar base): at a permeation temperature of $30^{\circ}C$, its $CO_2$ permeance and $CO_2/N_2$ separation factor were $2.5{\times}10^{-7}mol/m^2secPa$ and 34, respectively. The $CO_2$ and $N_2$ permeations were highly dependent on permeation test conditions (feed composition, feeding rate, feed pressure, He sweeping rate and permeation temperature). The results indicated that (i) $CO_2$ and $N_2$ permeations through NaY zeolite membrane are governed by surface and micropore diffusions, respectively, (ii) the preparation of NaY zeolite membrane with a large permeating area is one of the most difficult hurdles for its real applications, and (iii) the retardation of $N_2$ permeation is an effective key to improve $CO_2/N_2$ separation factor in NaY zeolite membrane.

Studies on the Rheological Properties of Korean Noodles III. Correlation between Mechanical Model Parameters and Sensory Quality of Noodles (한국 재래식 국수류의 유체변형성에 관한연구 제 3보 : 기계적 모델파라메터와 관능적 품질평가와의 상관관계)

  • Lee, Cherl-Ho;Kim, Cheol-Won
    • Korean Journal of Food Science and Technology
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    • v.15 no.3
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    • pp.302-306
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    • 1983
  • The changes in the mechanical model parameters during cooking and subsequent storage, were related to the sensory quality of the noodles. The sensory hardness and chewiness were tested by Milestone method and the overall preference was evaluated by hedonic scale test. Hardness was affected primarily by increasing cooking time and in lesser degree by storage time after cooking. Chewiness was diminished by increasing cooking time and subsequent storage. The preference of wheat flour noodle was not significantly affected by cooking time, while that of wheat·sweet potato starch noodle decreased significantly by excess cooking time. Instantaneous elasticity represented the softness of noodle. The elastic components and viscosity components had significant relationship with the sensory quality of wheat noodle. On the other hand the retardation time was important for the sensory quality of wheat-sweet potato starch noodle.

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DECREASE OF OXYGEN SATURATION DURING DENTAL TREATMENT UNDER GENERAL ANESTHESIA OF DOWN SYNDROME PATIENT WITH CONGENITAL HEART DISEASE -A CASE REPORT- (선천성 심장질환을 가진 다운증후군환자에서 치과치료를 위한 전신마취 시 산소포화도 하강 -증례보고-)

  • Seo, Kwang-Suk;Chang, Ju-Hea;Shin, Teo-Jeon;Kim, Hyun-Jeong
    • The Journal of Korea Assosiation for Disability and Oral Health
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    • v.5 no.1
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    • pp.18-22
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    • 2009
  • A 26-year-old female patient with Down syndrome visited to recieve dental treatment under gnenral anesthesia 6 years ago. The patient had difficulties in oral examination, radiograph taking and laboratory test. The patient had congenital heart disease and medical consultation based on the echocardiography was provided by a cardiologist indicating that the patient could tolearte general anesthesia during dental treatment. And two times of general anesthesia were administered during a dental treament with the interval of 3 years and no postoperpative complicaton was reported. At the third dental operation, the patient had a relatively good condition and her prescreening test revealed no abnormalities. Without further consultation with a cardiologist, general anesthesia was administered to the patient. Anaesthesia was based on thiopental and ventilation of desflurane and $N_2O$ in oxygen via an endotracheal tube with an appropriate monitoring. During the maintenance of anesthesia, the blood pressure of the patient started to drop and the oxygen saturation also began to decrease. Consequently, the proceding operation was discontinued and also inhalation anesthesia was ceased. As the patient was recovered from anesthesia, her systemic conditions were alleviated. After the complete recovery of the patient, she visited the cardiologist, and the cardiologic test revealed her severe right ventricular dilatation. In the anesthesia of patients with congenital heart disease, information on their systemic conditions needs to be undated from the medical consultation, which assures the safety of treatment.

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The Effect of Seasoning on the Intestinal Absorption -Absorption by Passive Transport and the Effect of Red Pepper- (조미료가 창자 운동과 흡수기능에 미치는 영향 -소장의 피동적 흡수에 대한 고추의 영향-)

  • Shin, Dong-Hoon;Kim, Joong-Soo;Koh, Jae-Pyong;Ahn, Seung-Woon
    • The Korean Journal of Physiology
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    • v.7 no.1
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    • pp.23-31
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    • 1973
  • Numerous factors concern with the absorption of substances through the membrane of the gastrointestinal tract. To simplify the experimental condition, present work has been restricted to observe the disappearance rate of substance from the intestinal loop which was made in the jejunum, 70 cm apart from the pylorus of the adult rabbit. The purpose of the study is to clarify the absorption of urea through the jejunal wall is solely attributable to the concentration difference between the luminal fluid and plasma, and to observe the effect of adding red pepper upon the rate of absorption. The rabbits were anesthetized with nembutal, 35mg/kg I.V. Jejunal loop was made by ligating at 2 spots, 70 cm and 80cm apart from the pylorus. After rinsing with normal saline solution through the polyethylene tubing inserted from the end of the loop, 8 ml of test solution was placed through the same tubing. The test solution contained 200 mg% of urea and 150mg% of polyethylene glycol(M.W. 4,000) in normal saline solution. Right after placing the test solution the first specimen was taken through the tubing, and successive samplings were performed at 5, 10, 20, and 30 minutes. Logarithm of the difference of urea concentration between the luminal fluid and plasma was plotted against time elapsed after the onset of the experiment. If straight line is revealed, it would verify the nature of transport mechanism as diffusion, obeying the Fick's principle. The concentration of polyethylene glycol (PEG) was also measured in order to examine the change in the volume. PEG was used as the marker substance because it is not absorbable in the intestinal tract. Consequently the concentration of PEG relates inversely to the volume of the loop. Instantaneous concentration of urea in the loop times the volume will give the amount of urea remaining in the luminal fluid. The change in the amount of any substance is directly relate to the volume of the compartment and differs from the change in the concentration which is independent of the volume. After completion of the experiment without red pepper, it was added in the test solution and was centrifuged after thorough mixing. Supernatant of the mixture was placed in the loop and similar sampling were performed with the same time intervals that of previous run in order to observe the effects of the red pepper on the passive transport of the water soluble small substance, urea. The results obtained were as follows: 1. Logarithm of the concentration difference of urea between the luminal fluid and plasma was diminished exponentially as time elapsed. The decay constant in the experiment without red pepper was 0.0563/min. By adding red pepper in the test solution as much as the concentration rose to 4,000 mg% and 8,000 mg%, the decay constants were lowered to 0.0493/min and to 0.0506/min, respectively. The time interval by which the concentration difference dropped to one half of the initial value was prolonged. Without red pepper the half concentration time was 13.30 minutes, and by adding extract of red pepper, 15.31 minutes and 15.71 minutes were revealed. 2. The profile of the diminishing rate of tile amount of urea was quite different from that of the concentration because of the change in the volume of the loop during the observed period. 3. By adding the extract of red pepper, it slowed down the rate of absorption of urea in the intestinal loop, suggesting an increase in the diffusional barrier. 4. Larger dosage of red pepper brought an increase in the secretion of intestinal fluid with concomitant expansion of the luminal volume, and the retardation of the absorption of urea was noticed. This effect was largely dependent on the sensitivity of the individual animal to the red pepper, extract. The amount of urea remained after 10 minutes interval was 55.5% of the initial amount in the experiment without red pepper. On the other hand it was not consistent after administration of red pepper, showing 50.6% and 66.5% of the initial figures by adding 400 mg and 800 mg of red pepper in the test solution, respectively. It was postulated that symptom of diarrhea often encountered by taking a hot (red pepper) food might be attributable to the increase of secretion and the retardation of absorption in the intestinal tract.

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A Study of Burden in Mothers of children With Congenital Metabolic Disorders (선천성 대사장애아 어머니의 부담감에 대한 연구)

  • Lee Myung Sook
    • Child Health Nursing Research
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    • v.1 no.1
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    • pp.26-36
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    • 1995
  • Children with metabolic disorders suffer from retardation and cognitive dysfunction. The task of caring for a mother may mean that she has less time and mony and more workload which may result in increased fatigue and depression and low well-being. The burden carried by mother due to the responsiblity take care of child. The descriptive study was done identify the burden in mother of children with metabolic disorders. The data was collected from November 1 to November 16, 1993. nineteen mothers were interviewed with metabolic disorders with questionnaire by mail. Burden was measured using existing tools by Zarit (1980), Montgomery(1985) . et al. Burden data was analyzed by the SPSS /pc+ program were tested using means, frequencies, Mann-Whitney, U-Wilcoxon Rank Sum Test and Kruskal-Wallis one way ANOVA The result of this study as follows : The meas score for burden was 2.8. (range from 34 to 4.95) The result of reiationship of demographic character and burden was no significant. In conclusion it was found that burden is correlated negatively to quality of life. In this study, burden was scored relatively low. Further qualitative research is needed to validats the nature of burden.

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Investigation of the Jetting Phenomena in Injection Molding for Various Injection Speeds, Resins and Mold Shapes (사출성형에서 사출속도, 수지의 종류 및 금형 형상에 따른 젯팅 현상에 관한 고찰)

  • 류민영;최종근;배유리
    • Transactions of Materials Processing
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    • v.12 no.1
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    • pp.3-10
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    • 2003
  • The formation of surface defects associated with Jotting in injection molding is related to the geometries of cavity and fate, operational conditions and the rheological properties of polymer. In this study we have examined jetting phenomena in injection molding process for the throe kinds of PCs which have different molecular weights and structures, PBT and PC/ABS alloy with several injection speeds. We have used various cavity shapes those are tensile, flexural and impact test specimens with various gates and cavity thicknesses. Through this study we have observed that the jetting is related to the dic swell of material. This means that the jotting is strongly affected by the elastic flow property rather than the viscous flow property in viscoelastic characteristics of molten polymer. Different resins have different elastic properties, and elastic flow behavior depends on the shear rate of flow, i.e. injection speed. Large die swell would eliminate jetting however, the retardation of die swell would stimulate jetting. In the point of mole design, reducing the thickness ratio of cavity to gate can reduce or eliminate jetting regardless of amount of elasticity of polymer melt.

The Fatigue Behavior of Tailored Welded Blank Sheet Metal by Laser Beam (레이저를 이용한 Tailored Blank 용접 판재의 피로거동)

  • 오택열
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.9 no.4
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    • pp.48-55
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    • 2000
  • For the Tailor Welded Blank sheet used for automobile body panel, the characteristics of fatigue strength and crack propagation behavior were studied. The thickness of specimens was joined to be same (0.9mm+0.9mm) and different (0.9mm+2.0mm) .As a base test, mechanical properties around weld zone were examined . The results indicated that there were no significant decreases in mechanical properties , but hardness around weld bead was 2.3 times greater than base material . The fatigue strength was the highest when the loading direction was parallel to the welding direction, which was about 85% of tensile strength of base material. It was decreased by 8.5% when the thickness of specimens and base metal was different, and it was increased by 25% when pres-strain was applied. The crack propagation rate was noticeably decreased around weld line and rapidly increased as it passed through weld line. Reviewing the shape of the crack propagation , crack width around weld line was around the weld zone due to retardation of crack growth , but is became narrow passing weld line due to decreased toughness.

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Characteristic as a Gene Delivery System of Water Soluble Chitosan Conjugated with Cationic Peptide (양이온 펩타이드가 컨쥬게이트된 수용성 키토산의 유전자 전달체로서의 특성)

  • Kim, Young-Min;Kim, Ji-Ho;Park, Seong-Cheol;Park, Yung-Hoon;Jang, Mi-Kyeong
    • KSBB Journal
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    • v.31 no.4
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    • pp.300-311
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    • 2016
  • Recently gene delivery has been designed newly using bioactive biomaterial and applied in the various field by many researchers. In this study, we proposed a new gene delivery system which has the capability of targeting effect in the specific tissue and remarkably enhanced transfection efficiency. We investigated $^1H-NMR$ spectroscopy, particle size analyzer and gel retardation to confirm the correct preparation of gene delivery. Also, we identified the hemo-compatibility of gene delivery by hemolysis assay, non-cytotoxicity by MTT test and transfection efficiency. The uptake mechanism of the gene carrier was confirmed using inhibitor agent such as sodium azide, indomethacin, quercetin, colchicine, and chloropromazine. As a results, it was identified that gene carrier prepared by in this study entered in the cell by the microtubule-dependent, energy-dependent and clathrin-mediated endocytosis pathway.