• 제목/요약/키워드: Retention behavior

검색결과 262건 처리시간 0.029초

Effect of Panax ginseng Extract on Passive Avoidance Retention in Old Rats

  • Jaenicke, Bernhard;Kim, Eun-Joo;Ahn, Jong-Woong;Lee, Hye-Sook
    • Archives of Pharmacal Research
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    • 제14권1호
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    • pp.25-29
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    • 1991
  • Female rats of two groups (6 and 27 months) were tested in the passive avoidance test to investigate the age-dependency of the learning ability. The results showed a significantly better avoidance behavior in the young adult animals compared to the older ones. The influence of a 13-day treatment with Panax ginseng (30 mg/kg/d, oral) on 27 month old rats caused a considerably prolonging of the latency time in comparison to the untreated control group of the same age. In the open field the treated rats exhibited neither an altered locomotion nor exploration nor a changed emotional reactivity which could explain the improved avoidance reaction.

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효소처리에 의한 양모섬유의 개질 (I) (Modification of Wool Fiber by Enzymatic Treatment (I))

  • Park, Jung-A;Park, Jeoung-Young;Lim, Yong-Jin
    • 한국염색가공학회지
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    • 제3권4호
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    • pp.7-12
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    • 1991
  • Wool gabardines were treated with alkaline proteases, and their tensile strerigth and dyeing behavior were obtained. Enzylon ASA 30 and Alcalase 2.5L DX did not show much effect on the weight loss of wool, but Esperase 8.0L decreased the weight of wool to a great extent. Pretreatment of wool with dichloroisocyarturic acid before protease-treatment increased the weight loss of wool considerably. Weight loss was accompanied by serious strength decrease and the use of sodium sulfate in the protease-treatment had not effect on the strength retention, only lowering the weight loss of wool. Protease-treatment of wool increased dyeability considerably, which may be due to the change in the inner structure of wool fiber by protease.

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$\alpha$-씨클로덱스트린을 이동상으로 사용한 몇 가지 페놀 유도체들의 크로마토그래피적 분리 (Chromatographic Separation of Some Phenol Derivatives Using $\alpha$-Cyclodextrin in Mobile Phase)

  • 문영자;김봉희
    • Environmental Analysis Health and Toxicology
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    • 제12권3_4호
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    • pp.75-84
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    • 1997
  • Chromatographic retention behavior and separation of various phenol derivatives on a Partisil 10 ODS 3 column-with mobile phase containing $\alpha$-cyclodextrin-were systematically studied. The decrease in k' values caused by the addition of cyclodextrins in the mobile phase was based on the formation of an inclusion complex, resulting in weakening of the hydrophobic interaction between solutes and the stationary phase. The content of the organic solvent in the mobile phase also influenced k' values of the solutes, and k' values increased with a decrease of the content of organic solvent in the mobile phase. A simple equation has been derived that reveals the hyperbolic dependence of the capacity factor on the total concentration of cyclodextrin. A plot of the reciprocal of the capacity factor against (CD)$_T$ gives a straight line and the dissociation constant, K$_D$, of the inclusion complex can be calculated from the slope. The capacity factor decreased with increasing temperature. The enthalpy was calculated from the slope of van't Hoff plots. Under optimum conditions, some mixtures of phenol derivatives were able to separated successfully.

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Analysis of behavior of bare and in-filled RC frames subjected to quasi static loading

  • Sandhu, Balvir;Sharma, Shruti;Kwatra, Naveen
    • Structural Engineering and Mechanics
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    • 제73권4호
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    • pp.381-395
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    • 2020
  • Study on the inelastic response of bare and masonry infilled Reinforced Concrete (RC) frames repaired using Carbon Fibre Reinforced Polymers (CFRP) and Glass Fiber Reinforced Polymers (GFRP) subjected to quasi- static loading is presented in the work. The hysteresis behaviour, stiffness retention, energy dissipation and damage index are the parameters employed to analyze the efficacy of FRP strengthening of bare and brick in-filled RC frames. It is observed that there is a significant improvement in load carrying capacity of brick infilled frame over bare RC frame. Also FRP strengthened brick infilled frame performs much better than FRP repaired bare frame under quasi static loading. Repair and retrofitting of brick infilled RC frame shows an improved load carrying and damage tolerance capacity than control frame.

Problem-solving approach for salbutamol analysis by HPLC during pharmaceutical assay

  • Gholizadeh-Hashjin, Aiesheh;Hamishehkar, Hamed;Monajjemzadeh, Farnaz
    • 분석과학
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    • 제35권5호
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    • pp.189-196
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    • 2022
  • When cationic basic compounds are chromatographed using hydro-organic mobile phase, the presence of anionic free silanols in the silica-based stationary phases results in broad and asymmetrical peaks. The addition of an ionic reagent to the mobile phase prevents analytes from accessing free silanols, improving peak shape. In this study, the chromatographic behavior of salbutamol sulfate as a basic compound was investigated under various conditions, including the use of different columns, mobile phases, and ion-pair reagents such as triethanolamine (TEA) and sodium heptane sulfonate (SHS). The retention and peak shape of chromatograms were both evaluated. The results show that pre-conditioning the column with TEA and including it in the mobile phase can prevent cationic analytes from accessing anionic silanols, resulting in improved peak shape. Furthermore, buffering the mobile phase is an important factor in keeping the pH constant throughout the process. The chosen method was validated in part. This study could be helpful for researchers and analyst to solve such problems with cationic basic components.

Variation of the Transport Property in Lap-Jointed YBCO Coated Conductor Tapes with Tension and Bending Deformation

  • Dizon, John Ryan C.;Bonifacio, Rolly;Park, Sung-Taek;Shin, Hyung-Seop
    • 한국초전도ㆍ저온공학회논문지
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    • 제9권4호
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    • pp.11-15
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    • 2007
  • In practical applications of HTS tapes for electric devices such as coils and power cables, the jointing of HTS tapes is inevitable even though long length tapes have recently been achieved. The critical current, $I_c$, degradation behaviors with tensile and bending deformations were investigated in commercially available YBCO coated conductor tapes. When the V-I relationship was measured at the jointed section of the lap-jointed YBCO CC tapes, the resistance at the joint decreased with increasing joint length. The critical load for 95% $I_c$ retention were determined for the IBAD and RABiTS YBCO tapes and they were 175 and 355N, respectively. Fracture occurred at the unjointed part which represents strong copper lamination and solder jointing. The electro-mechanical properties of lap-jointed CC tapes depended on the properties of single tapes. The V-I behavior under bending strain was similar with the tensile case.

유튜브 영상을 활용한 지속적인 학습의향 (Continuous Learning Intention Using YouTube Videos)

  • 고려천;유자양;양교
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2022년도 제66차 하계학술대회논문집 30권2호
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    • pp.713-715
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    • 2022
  • Video learning through YouTube has emerged as one of the most widely used instructional methods, yet relatively little research has been conducted on YouTube video users' willingness to use or behavior, so it is important to examine how to make and keep users' willingness to continue learning and to improve their retention rate for effective online learning. With reference to perceived value theory and utilizing an ECM perspective, the authors construct a model of YouTube video continuous learning intention and investigate the influence of perceived value and satisfaction on users' willingness to use YouTube videos for continuous learning.

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Employees' Intention to Leave Job: The Case of Micro Finance Institution

  • Rabin Subedi;Surendra Neupane;Raju Ram Adhikari
    • Journal of Information Technology Applications and Management
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    • 제28권5호
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    • pp.51-60
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    • 2021
  • The main purpose of this study is to examine the factors that influence the employee's intention to leave the current job. A descriptive survey design was conducted and primary data were collected by using questionnaire. The study was based on random sampling; a sample of 200 was drawn from the employees who work in different micro finance institutions in Nepal. For the data analysis percentage analysis and chi square-test were used. The study revealed that salary, working condition, career growth, supervisor behavior and outstation influence the job quitting process. The study also defined the association between the reasons for leaving job such as salary, working condition, career growth supervisor behaviour & outstation and satisfaction, time spent in the organisation, training & development facility, frequency of changing job & encourage from immediate boss. This study establishes the importance of intentions of employees to quit job and provides further evidence in revealing the intentions to quit among the employees.

Elution Behavior of Protein and Pullulan in Asymmetrical Flow Field-flow Fractionation (AsFlFFF)

  • Ji, Eun-Sun;Choe, Seong-Ho;Yun, Guk-Ro;Chun, Jong-Han;Lee, Seung-Ho
    • Bulletin of the Korean Chemical Society
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    • 제27권9호
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    • pp.1433-1438
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    • 2006
  • An AsFlFFF channel was designed and built, and then tested for analysis of pullulans and proteins. Pullulans and proteins having various nominal molecular weights were injected at various conditions of the cross-flow rate ($F_c$) and the channel-out flow rate ($F_{out}$). The retention (measured by the retention ratio R) and the zone broadening (measured by the plate height H) were measured, and then compared with theory. When the incoming flow rate, $f_{in}$ (and thus $F_{out}$) was varied with $F_c$ fixed at 2.5 mL/min, the plate height measured for the pullulan with nominal molecular weight (M) of about 100,000 showed the trend expected by the longitudinal diffusion theory (H decreases with increasing flow rate). In contrast, when $F_{out}$ was varied with the flow rate ratio, $F_c/F_{out}$, fixed constant at 5, the plate height measured for the same sample showed the trend expected from the non-equilibrium theory (H increases with increasing flow rate). Calibration plots (log D vs. log M) obtained with pullulans and proteins were not coincide, probably due to the difference in molecular conformation, suggesting the analysis of pullulans and proteins using AsFlFFF requires independent calibration. It was found that the linearity of the protein-calibration plot was improved by using a buffer solution as the carrier.

일부 가철성 의치장착 노인의 의치만족도 영향 요인 (Influencing factors of removable denture satisfaction in the elderly)

  • 윤혜정;임선아;정은주
    • 한국치위생학회지
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    • 제15권3호
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    • pp.435-442
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    • 2015
  • Objectives: The purpose of this study was to investigate the influencing factors of removable dentures satisfaction in the elderly. Methods: A self-reported questionnaire was filled out by 256 elderly in Jeollanam-do from September 1, 2013 to June 30, 2014. The questionnaire consisted of general characteristics of the subjects, denture related characteristics systemic health characteristics and dental health behavior. Removable dentures satisfaction was adapted from Ban. The questionnaire for Removable dentures satisfaction included general treatment satisfaction, masticatory function satisfaction, denture retention satisfaction, aesthetic satisfaction measured by Likert 5 scale. Cronbach's alpha was 0.850 in the study. Data were analyzed for a t-test, one-way ANOVA and multiple regression analysis by using SPSS(SPSS 18.0, USA) program. Results: According to subjective and systemic health condition and oral health condition, there was a statistically significant increase in general satisfaction of treatment, masticatory satisfaction of function, denture satisfaction of retention, aesthetic satisfaction. The overall satisfaction for removable denture showed a significant improvement. In the multiple regression analysis, variation of removable denture satisfaction was positively associated with oral health status{good(b=0.736, p=0.000)}, denture treatment services{dental hospital clinic(b=0.327, p=0.023)}, and systemic health status{good(b=0.241, p=0.047)}. Conclusions: Satisfaction of removable dentures may have a positive impact on oral health condition, hospital type, and associated systemic disease. It is necessary to develop incremental care programs for oral health and systemic health and to make public opinion to encourage the program.