• Title/Summary/Keyword: model B3

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Influence of Column Aspect Ratio on the Hysteretic Behavior of Slab-Column Connection (슬래브-기둥 접합부의 이력거동에 대한 기둥 형상비의 영향)

  • Choi, Myung-Shin;Cho, In-Jung;Ahn, Jong-Mun;Shin, Sung-Woo
    • Journal of the Korea Concrete Institute
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    • v.19 no.4
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    • pp.515-525
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    • 2007
  • In this investigation, results of laboratory tests on four reinforced concrete flat plate interior connections with elongated rectangular column support which has been used widely in tall residential buildings are presented. The purpose of this study is to evaluate an effect of column aspect ratio (${\beta}_c={c_1}/{c_2}$=side length ratio of column section in the direction of lateral loading $(c_1)$ to the direction of perpendicular to $c_1$) on the hysteretic behavior under earthquake type loading. The aspect ratio of column section was taken as $0.5{\sim}3\;(c_1/c_2=1/2,\;1/1,\;2/1,\;3/1)$ and the column perimeter was held constant at 1200mm in order to achieve nominal vertical shear strength $(V_c)$ uniformly. Other design parameters such as flexural reinforcement ratio $(\rho)$ of the slab and concrete strength$(f_{ck})$ was kept constant as ${\rho}=1.0%$ and $f_{ck}=40MPa$, respectively. Gravity shear load $(V_g)$ was applied by 30 percent of nominal vertical shear strength $(0.3V_o)$ of the specimen. Experimental observations on punching failure pattern, peak lateral-load and story drift ratio at punching failure, stiffness degradation and energy dissipation in the hysteresis loop, and steel and concrete strain distributions near the column support were examined and discussed in accordance with different column aspect ratio. Eccentric shear stress model of ACI 318-05 was evaluated with experimental results. A fraction of transferring moment by shear and flexure in the design code was analyzed based on the test results.

A Proposal on a Management Model Applicable to Visiting Nursing Program for a Low-income Group (저소득층 방문간호 관리를 위한 제안 - 강북구 방문간호 대상자를 중심으로-)

  • Ko Mee-Ja
    • Journal of Korean Public Health Nursing
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    • v.10 no.1
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    • pp.118-138
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    • 1996
  • Because of accelerated urbanization public body visiting nursing project that started according as matter of health on urban class in the lower brackets of income was concentrated on Social interests has a unsatisfied points to propel project efficiently from the lack of rating materials. Therefore centering around written contents in documentary literature of citizen health by household in five years from starting year of project to now. visiting frequency by medical manpower was evaluated quantitatively and qualitatively in aspect of management hereupon. for the sake of giving a basic materials for public health project of this field. This research presents documentary literature of citizen health which become materials is that as one person's charged region of nurse in duty scale. district is Kang-Buck Gu. the object is resident in the lower brackets of income grounded livelihood protection law and who is admitted by the head of organ~chief of health care). and the number of material centering around the head of a household is 415 copy. The result of research is summarized. as follow. 1. Average visiting frequency examinated by medical manpower show difference according to valuables of supervision characteristics namely average visiting. Frequency of nurse has long term residence in case registration season is early and supervision season is the first year and is high incase a kind of house is unlicdnsed mountain town. Average visiting frequency with doctor is high incase supervision season is the first year and the medical insurance system is admitted by chief of health care. That shows that a man of discomfort behavior left alone are yet many in local society. The meaning of this result shows that the continuity of official relation about class in the lowest brackets of income of long term residence goes well between househole who is a user of visiting nursing service of the object according to midway income under management influences a given duty of nurse s and so causes quantitative decrease. 2. In case behavier and condition of health that nurse diagnoses are bad. as the type matter is a lack of health and the number of patient is large. the average visiting frequency of nurse is high. because average visiting frequency with doctor is high as the condition of health is bad and the number of patient is large. That is similar with that of nurse. CD Average visiting frequency of nurse s seen by matter of disease is very high only in apoplexy by 39.50 and is confined within limits from 7.63 to 11.36 in other disease. But average visiting frequency with doctor is double as many as that of nurse but defined in apoplexy hypertension and articulate. (1) Average visiting frequency of nurse by existence in inoculation of hepatitis is low by 6.73 in unidentified group and very high by 26.89 in group of non-inoculation and the case of the antigenic positive man of B type hepatitis or epileptic who can't be inoculated shows 13.00 and that even family nursing service is needed to them. That result shows that though one person nurse of local charge has a large scale of duty. as visting nursing service is given a class who has a large demand preferentially by respectively accurate nursing diagnosis. the number of diagnosis service is similar with it. 3. During five years. average visiting frequency of nurse is 10.84 and average visiting frequency with doctor is 76.50 seeing from the official scale of nurse. visiting by household is performed two more per year to the average. Seeing this by type of service. average visiting frequency of nurse is higher in indirectly nursing than in directly nursing and that suggests that at the time of visiting household nurse performs education of protection lively save patient but at the time of contrastedly visiting with doctor. directly nursing is more contents of service show no difference by man power and medication dressing by demand is 14.3 and 18.6 the aid of hardship term of doctor and nurse is high by 18.7 and 17.00 in the request of hospitalization when seeing by demands. 4. Action by turns exemplified 1994 is well in sequence of 2/4 turn. 3/4 turn. 1/4 turn. 4/4 turn. When seen by average visiting frequency of nurse but gradually is even. Without difference by turns. average visiting frequency of doctor is much higher in 1/4 turn than other turns. Type of service by turns is all even but directly nursing is inactive in 4/4 and indirectly nursing. Very increases in 4/4 and so. Nurse's quantity of duty is plentiful that shows that by evaluation of last turn and plan of project. Contents of service follows that medication and dressing is the highest by' 5.57 in 1/4turn. goes down gradually by turn. becomes 3.57 in 3/4 turn. and increases again by 4.83 in 4/4 turn. the rest service is higher in 2/4 turn than other turns. 5. Total visiting frequency of nurse is explained to total $37.5\%$ by six valuables of visiting frequency of doctor. nursing demand. demand of diagnosis. condition of behavior. year. Special terms and magnitude of influential power is the same as sequence of enumerated valuables. Namely. the higher the visiting frequency of doctor. the bigger nursing and demand of diagnosis is. the worse the condition of behavior is. the older the object is and the more the household of special terms is. the high total visiting frequency of nurse is.

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The Comparison of Existing Synthetic Unit Hydrograph Method in Korea (국내 기존 합성단위도 방법의 비교)

  • Jeong, Seong-Won;Mun, Jang-Won
    • Journal of Korea Water Resources Association
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    • v.34 no.6
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    • pp.659-672
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    • 2001
  • Generally, design flood for a hydraulic structure is estimated using statistical analysis of runoff data. However, due to the lack of runoff data, it is difficult that the statistical method is applied for estimation of design flood. In this case, the synthetic unit hydrograph method is used generally and the models such as NYMO method, Snyder method, SCS method, and HYMO method have been widely used in Korea. In this study, these methods and KICT method, which is developed in year 2000, are compared and analyzed in 10 study areas. Firstly, peak flow and peak time of representative unit hydrograph and synthetic unit hydrograph in study area are compared, and secondly, the shape of unit hydrograph is compared using a root mean square error(RMSE). In Nakayasu method developed in Japan, synthetic unit hydrograph is very different from peak flow, peak time, and the shape of representative unit hydrograph, and KICT method(2000) is superior to others. Also, KICT method(2000) is superior to others in the aspects of using hydrologic and topographical data. Therefore, Nakayasu method is not a proper in hydrological practice. Moreover, it is considered that KICT model is a better method for the estimation of design flood. However, if other model, i.e. SCS method, Nakayasu method, and HYMO method, is used, parameters or regression equations must be adjusted by analysis of real data in Korea.

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Evaluations of Ecological Habitat, Chemical Water Quality, and Fish Multi-Metric Model in Hyeongsan River Watershed (형산강 수계의 생태 서식지, 화학적 수질 및 어류의 다변수모델 평가)

  • Kim, Yu-Pyo;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.279-287
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    • 2010
  • This study was to evaluate ecological conditions of Hyeongsan River watershed from April to September 2009. The ecological health assessments was based on Qualitative Habitat Evaluation Index (QHEI), water chemistry during 2000~2009, and the fish multi-metric model, Index of Biological Integrity (IBI). For the study, the models of IBI and QHEI were modified as 8 and 11 metric attributes, respectively. Values of IBI averaged 25.4 (n=6), which is judged as a "fair" condition (C) after the criteria of Barbour et al. (1999). The distinct spatial variation was found in the IBI. Physical habitat health, based on the values of QHEI, varied from 76 in the downriver (H6) to 150.5 in the headwater (H1) and was evidently more disturbed in the downriver reach. Values of BOD and COD averaged 2.4 $mgL^{-1}$ (range: 0.3~13.8 $mgL^{-1}$) and 4.3 $mgL^{-1}$ (scope: 0.6~12.8 $mgL^{-1}$), respectively during the study period. Total nitrogen (TN) and total phosphorus (TP) averaged 3.0 $mgL^{-1}$ and 103.5 ${\mu}gL^{-1}$, respectively, indicating a severe eutrophication, and the nutrients increased more in the downriver than the headwater. Overall, physical, chemical and IBI parameters showed a typical downriver degradation along main axis of the river from the headwater-to-the downriver. This was mainly attributed to livestock waste and residential influences along with industrial discharge from the urban region.

Studies on the Derivation of the Instantaneous Unit Hydrograph for Small Watersheds of Main River Systems in Korea (한국주요빙계의 소유역에 대한 순간단위권 유도에 관한 연구 (I))

  • 이순혁
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.19 no.1
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    • pp.4296-4311
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    • 1977
  • This study was conducted to derive an Instantaneous Unit Hydrograph for the accurate and reliable unitgraph which can be used to the estimation and control of flood for the development of agricultural water resources and rational design of hydraulic structures. Eight small watersheds were selected as studying basins from Han, Geum, Nakdong, Yeongsan and Inchon River systems which may be considered as a main river systems in Korea. The area of small watersheds are within the range of 85 to 470$\textrm{km}^2$. It is to derive an accurate Instantaneous Unit Hydrograph under the condition of having a short duration of heavy rain and uniform rainfall intensity with the basic and reliable data of rainfall records, pluviographs, records of river stages and of the main river systems mentioned above. Investigation was carried out for the relations between measurable unitgraph and watershed characteristics such as watershed area, A, river length L, and centroid distance of the watershed area, Lca. Especially, this study laid emphasis on the derivation and application of Instantaneous Unit Hydrograph (IUH) by applying Nash's conceptual model and by using an electronic computer. I U H by Nash's conceptual model and I U H by flood routing which can be applied to the ungaged small watersheds were derived and compared with each other to the observed unitgraph. 1 U H for each small watersheds can be solved by using an electronic computer. The results summarized for these studies are as follows; 1. Distribution of uniform rainfall intensity appears in the analysis for the temporal rainfall pattern of selected heavy rainfall event. 2. Mean value of recession constants, Kl, is 0.931 in all watersheds observed. 3. Time to peak discharge, Tp, occurs at the position of 0.02 Tb, base length of hlrdrograph with an indication of lower value than that in larger watersheds. 4. Peak discharge, Qp, in relation to the watershed area, A, and effective rainfall, R, is found to be {{{{ { Q}_{ p} = { 0.895} over { { A}^{0.145 } } }}}} AR having high significance of correlation coefficient, 0.927, between peak discharge, Qp, and effective rainfall, R. Design chart for the peak discharge (refer to Fig. 15) with watershed area and effective rainfall was established by the author. 5. The mean slopes of main streams within the range of 1.46 meters per kilometer to 13.6 meter per kilometer. These indicate higher slopes in the small watersheds than those in larger watersheds. Lengths of main streams are within the range of 9.4 kilometer to 41.75 kilometer, which can be regarded as a short distance. It is remarkable thing that the time of flood concentration was more rapid in the small watersheds than that in the other larger watersheds. 6. Length of main stream, L, in relation to the watershed area, A, is found to be L=2.044A0.48 having a high significance of correlation coefficient, 0.968. 7. Watershed lag, Lg, in hrs in relation to the watershed area, A, and length of main stream, L, was derived as Lg=3.228 A0.904 L-1.293 with a high significance. On the other hand, It was found that watershed lag, Lg, could also be expressed as {{{{Lg=0.247 { ( { LLca} over { SQRT { S} } )}^{ 0.604} }}}} in connection with the product of main stream length and the centroid length of the basin of the watershed area, LLca which could be expressed as a measure of the shape and the size of the watershed with the slopes except watershed area, A. But the latter showed a lower correlation than that of the former in the significance test. Therefore, it can be concluded that watershed lag, Lg, is more closely related with the such watersheds characteristics as watershed area and length of main stream in the small watersheds. Empirical formula for the peak discharge per unit area, qp, ㎥/sec/$\textrm{km}^2$, was derived as qp=10-0.389-0.0424Lg with a high significance, r=0.91. This indicates that the peak discharge per unit area of the unitgraph is in inverse proportion to the watershed lag time. 8. The base length of the unitgraph, Tb, in connection with the watershed lag, Lg, was extra.essed as {{{{ { T}_{ b} =1.14+0.564( { Lg} over {24 } )}}}} which has defined with a high significance. 9. For the derivation of IUH by applying linear conceptual model, the storage constant, K, with the length of main stream, L, and slopes, S, was adopted as {{{{K=0.1197( {L } over { SQRT {S } } )}}}} with a highly significant correlation coefficient, 0.90. Gamma function argument, N, derived with such watershed characteristics as watershed area, A, river length, L, centroid distance of the basin of the watershed area, Lca, and slopes, S, was found to be N=49.2 A1.481L-2.202 Lca-1.297 S-0.112 with a high significance having the F value, 4.83, through analysis of variance. 10. According to the linear conceptual model, Formular established in relation to the time distribution, Peak discharge and time to peak discharge for instantaneous Unit Hydrograph when unit effective rainfall of unitgraph and dimension of watershed area are applied as 10mm, and $\textrm{km}^2$ respectively are as follows; Time distribution of IUH {{{{u(0, t)= { 2.78A} over {K GAMMA (N) } { e}^{-t/k } { (t.K)}^{N-1 } }}}} (㎥/sec) Peak discharge of IUH {{{{ {u(0, t) }_{max } = { 2.78A} over {K GAMMA (N) } { e}^{-(N-1) } { (N-1)}^{N-1 } }}}} (㎥/sec) Time to peak discharge of IUH tp=(N-1)K (hrs) 11. Through mathematical analysis in the recession curve of Hydrograph, It was confirmed that empirical formula of Gamma function argument, N, had connection with recession constant, Kl, peak discharge, QP, and time to peak discharge, tp, as {{{{{ K'} over { { t}_{ p} } = { 1} over {N-1 } - { ln { t} over { { t}_{p } } } over {ln { Q} over { { Q}_{p } } } }}}} where {{{{K'= { 1} over { { lnK}_{1 } } }}}} 12. Linking the two, empirical formulars for storage constant, K, and Gamma function argument, N, into closer relations with each other, derivation of unit hydrograph for the ungaged small watersheds can be established by having formulars for the time distribution and peak discharge of IUH as follows. Time distribution of IUH u(0, t)=23.2 A L-1S1/2 F(N, K, t) (㎥/sec) where {{{{F(N, K, t)= { { e}^{-t/k } { (t/K)}^{N-1 } } over { GAMMA (N) } }}}} Peak discharge of IUH) u(0, t)max=23.2 A L-1S1/2 F(N) (㎥/sec) where {{{{F(N)= { { e}^{-(N-1) } { (N-1)}^{N-1 } } over { GAMMA (N) } }}}} 13. The base length of the Time-Area Diagram for the IUH was given by {{{{C=0.778 { ( { LLca} over { SQRT { S} } )}^{0.423 } }}}} with correlation coefficient, 0.85, which has an indication of the relations to the length of main stream, L, centroid distance of the basin of the watershed area, Lca, and slopes, S. 14. Relative errors in the peak discharge of the IUH by using linear conceptual model and IUH by routing showed to be 2.5 and 16.9 percent respectively to the peak of observed unitgraph. Therefore, it confirmed that the accuracy of IUH using linear conceptual model was approaching more closely to the observed unitgraph than that of the flood routing in the small watersheds.

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EXPRESSION OF OSTEOGENESIS RELATED FACTORS ACCORDING TO DISTRACTION RATE IN THE DISTRACTION OSTEOGENESIS (신연 골형성술시 신연속도에 따른 골형성 관여 인자의 발현)

  • Jee, Yu-Jin;Kim, Yeo-Gab
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.34 no.3
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    • pp.250-265
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    • 2008
  • Distraction osteogenesis is a well-established clinical treatment for limb length discrepancy and skeletal deformities. Appropriate mechanical tension-stress is believed not to break the callus but rather to stimulate osteogenesis. In contrast to fracture healing, the mode of bone formation in distraction osteogenesis is primarily intramembranous ossification. Although the biomechanical, histological, and ultrastructural changes associated with distraction osteogenesis have been widely described, the basic biology of the process is still not well known. Moreover, the molecular mechanisms in distraction osteogenesis remain largely unclear. Recent studies have implicated the growth factor cascade is likely to play an important role in distraction. And current reserch suggested that mechanical tension-stress modulates cell shape and phenotype, and stimulates the expression of the mRNA for bone matrix proteins. The purpose of this study is to examine the pattern of expression of growth factors($TGF-{\beta}1$, IGF-I, bFGF) and extracellular matrix proteins(osteoclacin, osteonectin) related to osteogenesis by osteodistraction of the mandible in rabbits. 24 rabbits is used for this experiment. Experimental group are gradual distraction(0.7mm, twice/day), acute distraction(1.4mm, twice/day) and control group is only osteotomized. After 5 days latency, osteotomic site is distracted for each 7 days and 3.5 days. Consolidation period is 28 days. The animal is sacrificed at the 3th, 7th, 14th, 28th. The distracted bone is examined by immunohistochemical analysis and RT-PCR analysis. The results obtained from this study were as follow : No significant difference was found on clinical examination according to distraction rate, but gradual distraction was shown to improve regenerate bone formation on radiographic and histologic examination. Growth factors and extracelluar matrix proteins expression increased in distraction group than control group. From these results, it could be stated that graudal distraction is shown to improve and accelerate bone formation and mechanical stress like distraction has considerable effects on osteogenesis related factors. And rabbit is the most appropriate animal model for further reseach on the molecular mechanisms that mediate osteodistraction. It is believed that understanding the biomolecular mechanisms that mediate distraction osteogenesis may guide the development of targeted strategies designed to improve distraction osteogenesis and accelerate bone healing.

Effect of irradiation on cell cycle, cell death and expression of its related proteins in normal human oral keratinocytes (방사선조사가 사람 정상 구강각화 세포의 세포주기, 세포사 및 수종 단백질의 발현에 미치는 영향)

  • Kang Mi-Ae;Heo Min-Suk;Lee Sam-Sun;Oh Sung-Ock;Lee Sul-Mi;Jeon In-Seong;Choi Soon-Chul;Park Tae-Won
    • Imaging Science in Dentistry
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    • v.33 no.3
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    • pp.143-149
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    • 2003
  • Purpose: To investigate the radiosensitivity of the normal human oral keratinocytes (NHOK), and the effect of irradiation on cell cycle and protein expression. Materials and Methods: To evaluate the radiosensitivity of NHOK, the number of colonies and cells were counted after irradiation and the SF2 (survival fraction at 2Gy) value, and the cell survival curve fitted on a linear-quadratic model were obtained. LDH analysis was carried out to evaluate the necrosis of NHOK at 1, 2, 3, and 4 days after 2, 10, and 20 Gy irradiation. Cell cycle arrest and the induction of apoptosis were analyzed using flow cytometry at 1, 2, 3, and 4 days after 2, 10, and 200y irradiation. Finally, proteins related cell cycle arrest and apoptosis were analysed by Western blot. Results: The number of survived cell was significantly decreased in a dose-dependent manner. The cell survival curve showed SF2, α, and β values to be 0.568, 0.209, and 0.020 respectively. At 200y irradiated cells showed higher optical density than the control group. After irradiation, apoptosis was not observed but G2 arrest was observed in the NHOK cells. 1 day after 10 Gy irradiation, the expression of p53 remained unchanged, the p2l/sup WAF1/Cipl/ increased and the mdm2 decreased. The expression of bax, bcl-2, cyclin B1, and cyclin D remained unchanged. Conclusion: These results indicate that NHOK responds to irradiation by G2 arrest, which is possibly mediated by the expression of p21/sup WAFl/Cipl/, and that cell necrosis occurs by high dose irradiation.

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Physical Colorimetric Properties and Psychological Sensibility Factor of Naturally Dyed Fabrics (천연염색직물의 물리적 색채 특성과 심리적 감성 요인)

  • Lee, Eu-Gene;Lee, Kyung-hyun;Cho, Gil-Soo
    • Science of Emotion and Sensibility
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    • v.19 no.3
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    • pp.3-14
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    • 2016
  • This study is aimed to measure the physical colorimetric property according to three conditions, natural dyestuffs (Gardenia, Sappan wood, Lac, Gardenia blue, Mugwort, and Indigo), fabric types (cotton, silk), and presence of mordant (without, with), and then to evaluate the psychological sensibility. Also, to perform analysis of variance (ANOVA) to find out the differences of physical properties according to the three natural dyeing conditions, and to analyze the relationship between physical property and psychological property by Pearson's correlation analysis and then suggest the prediction model by regression analysis using SPSS program (ver. 21.0). Finally, to propose a certain sensibility image map of naturally dyed fabrics, MDS (Multidimensional Scaling) was used, and as a result, Gardenia dyed fabrics having the color sensibilities such as 'hard' and 'heavy' were suggested to evoke masculine image, and to evoke feminine image, Sappan wood and Lac having 'bright', 'transparent', 'soft' and 'light' sensibilities were suggested. Natural image might be induced by using 'subdued' Mugwort dyed fabrics, and active image might be induced by using 'showy' Indigo dyed fabric.

Efficacy of Mixture of Lactic Acid Bacteria (LAB) and Bifidobacteria Supplement in the Management of Constipation; Demonstration of Functionality in Animal and Clinical Trials (한국형 Bifidobacterium longum SPM1205 혼합제제의 변비 개선 효과)

  • Kim, Jung-Rae;Lee, Do-Kyung;Baek, Eun-Hye;An, Hyang-Mi;Yang, Hwan-Jin;Kim, Mi-Jin;Choi, Kyung-Soon;Yun, Mi-Eun;Jung, Yi-Jung;Oh, Pok-Ja;Chung, Myung-Jun;Ha, Nam-Joo
    • Korean Journal of Microbiology
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    • v.46 no.1
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    • pp.52-62
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    • 2010
  • The aim of this study was to evaluated the efficacy of mixture of Lactic Acid Bacteria (LAB) and bifidobacteria supplement, which are contained with Lactobacillus acidophilus, Bifidobacterium longum SPM1205, and Pediococcus pentosaceus for the management of constipation in animal model and clinical trials. 5 ICR mice and 4 female constipation subjects were orally taken mixture of LAB and bifidobacteria for 2 weeks. We investigated the number of fecal LAB and harmful enzymes activities before and after mixture of LAB and bifidobacteria application. As a result, fecal LAB count was increased and harmful enzymes activities of intestinal microflora were generally decreased after mixture of LAB and bifidobacteria application. Also, 61 female subjects were randomly assigned to receive either mixture of LAB and bifidobacteria or lactose and were taken three times a day for 2 weeks. Then, we analyzed mixture of LAB and bifidobacteria effect through the questionnaires. Daily consumption of this mixture of LAB and bifidobacteria improved the constipation in constipation group (56.3%) compared with lactose application group (26.7%). Furthermore, after mixture of LAB and bifidobacteria treatment, frequency of hard stool decreased from 0.22 to 0.03. These results indicated that mixture of LAB and bifidobacteria application is effective to improve the constipation.

EFFECTS Of VARIOUS SILANE COUPLING AGENTS ON THE STRENGTH AND THE SURFACE ROUGHNESS OF GLASS FIBER-ADDED PMMA RESIN (수종의 실란처리 유리섬유를 첨가한 의치상용 레진의 강도변화 및 마모전.후 표면성상분석)

  • Lee, Sang-Il;Kim, Chang-Whe;Lim, Young-Jun;Kim, Myung-Joo;Yun, Suk-Dae
    • The Journal of Korean Academy of Prosthodontics
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    • v.45 no.4
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    • pp.457-468
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    • 2007
  • Statements of problem: The fracture of acrylic resin dentures remains an unsolved problem. Therefore, many investigations have been performed and various approaches to strengthening acrylic resin, for example, the reinforcement of heat-cured acrylic resin using glass fibers, have been suggested over the years. Silane is important for bonding between glass fiber and resin. Purpose: The aim of the present study was to investigate the effect of various silane on the strength of PMMA resin and roughness of resin-glass fiber complex after abrasion test. Material and methods: 3mm glass fiber (Chopped strand, Hankuk fiber Co., Milyang, Korea) was treated with 3 kinds of silane (MPS, EPS, APS) (Sila-ace, Chisso chemical, Tokyo, Japan) and mixed with PMMA resin(Vertex RS, Vertex Dental B.V., Zeist, Netherlands). Transverse strength and Young's modulus was measured using Instron (Instron model 4466, Instron, Massachusetts, USA). After abrasion test (The 858 Mini Bionix II Test System, MTS System Co., Minnesota, USA) surface roughness was evaluated using tester (Form Talysurf plus, Taylor Hopson Ltd., Leicester England). Examination of scanning electron microscope was also performed. Results: Within this study, the following conclusions were drawn. 1. Surface treatment of glass fiber with MPS and APS increased transverse strength of PMMA resin complex, but surface treatment with EPS decreased transverse strength of PMMA resin complex (p<0.05). 2. Silane treated glass fiber increased Young's modulus of PMMA resin complex compared to desized glass fiber (p<0.05). 3. Roughness increased after abrasion test in case of PMMA resin reinforced with desized glass fiber (p<0.05). 4. Roughness change was not observed after abrasion test in case of PMMA resin reinforced with silane treated glass fiber (p>0.05).