• 제목/요약/키워드: concentration effect

검색결과 18,390건 처리시간 0.04초

The Effects of the Meditation Music and Lumbar Stabilization Exercise on Concentration, Balance and Muscle Activity in Elderly

  • Lee, Sang-Bin
    • 국제물리치료학회지
    • /
    • 제2권1호
    • /
    • pp.260-266
    • /
    • 2011
  • The purpose of this study was to investigate the effects of meditation music with lumbar stabilization exercise on balance, concentration and muscle activation. Participants are divided into Group A and Group B. Group A listened to meditation music while doing 4 sets of lumbar stabilization exercise. Group B did not listen to meditation music while doing 4 sets of lumbar stabilization exercise. Surface EMG data was obtained rectus abdominis, external oblique, erector spinae, multifidus muscle during lumbar stabilization exercise. To examine the effect of before-after experiment for concentration and balance, paired t-test was adopted. Changes in EMG data of each muscles were analyzed by independence t-test. There were statistically significant increasing at concentration level and balance level in Group A. But significant difference was not shown in muscle activation. The clinical effect of the meditation music with lumbar stabilization exercise was investigated in this study with more excellent results in concentration and balance. In conclusion, these results suggest that meditation music and lumbar stabilization exercise may be useful in elderly people.

Effect of Impinging Plate on Exhaust Emission and Engine Performance in Diesel Engine

  • Jin, Yong-Su;Kim, Jae-Dong;Kim, Yeong-Sik
    • 동력기계공학회지
    • /
    • 제19권4호
    • /
    • pp.82-88
    • /
    • 2015
  • The purpose of this study is to investigate the effect of the impinging plate on combustion process in Diesel engine. Especially, the variation of exhaust emission and engine performance by the change of fuel injection timing and fuel injection pressure between the trial engine with impinging plate and the prototype engine were examined. The nitrogen oxide concentration of the trial engine decreased more than 50% compared to the prototype engine, however, smoke concentration of the trial engine indicated higher degree than the prototype engine. The smoke concentration, fuel consumption rate and exhaust gas temperature decreased as the fuel injection timing become faster, whereas the nitrogen oxide concentration decreased as the fuel injection timing is retarded. The nitrogen oxide concentration, fuel consumption rate and exhaust gas temperature decreased as the fuel injection pressure become lower. But smoke concentration decreased as the fuel injection pressure become higher.

입자 농도가 Digital Holographic PTV 측정에 미치는 영향에 관한 연구 (Effect of Particle Concentration on Digital Holographic PTV Measurement)

  • 김석;이상준
    • 대한기계학회논문집B
    • /
    • 제30권10호
    • /
    • pp.929-934
    • /
    • 2006
  • The digital HPTV(holographic particle tracking velocimetry) velocity field measurement system consists of four steps: recording, numerical reconstruction, particle extraction and velocity extraction. In the velocity extraction process, we improved the two frame PTV algorithm to extract 3-D displacement information of each particle located in 3D space. Because a digital CCD camera was used, some factors such as spatial resolution, numerical aperture, and particle concentration influenced on the performance of the developed digital HPTV. Especially, the particle concentration $(C_o)$ affected the reconstruction efficiency and recovery ratio in the numerical reconstruction and particle extraction procedure. In this paper, the effect of particle concentration reconstruction efficiency and recovery ratio were analyzed experimentally. Optimal particle concentration was found to be in the range of $C_o=11{\sim}17\;particles/mm^3$.

Suppressed 이온 크로마토그래피에서 과량의 양이온이 낮은 농도의 음이온 분석에 미치는 영향 (The Effect of High Concentration Cation Matrix on the Analysis of the Low Anion Concentration in Suppressed Ion Chromatography)

  • 강미정;이석근
    • 분석과학
    • /
    • 제11권6호
    • /
    • pp.495-498
    • /
    • 1998
  • The effect of high concentration ion matrix on the analysis of low anion concentration in the suppressed ion chromatography was studied. The anions studied were $Br^-$, $NO_3{^-}$, $HPO_4^{2-}$, $SO_4^{2-}$, and $C_2O_4^{2-}$ in the presence of excess NaCl and $CaCl_2$. In this study we suggested that the erroneous results in the suppressed ion chromatographic determination of small concentration of anions were not caused by the interaction of large amount of cation in the suppressor, but by the interaction of cation with concerned anion in the original solution. The error in the analysis of such anion can not be eliminated just by dilution. Therefore, we suggested that standard addition method might be adequate for analyses of those samples.

  • PDF

DMAB를 사용한 무전해 Ni-B 합금 도금 I. 오스테나이트 스텐레스강 상의 석출반응에 대한 전기화학적 거동 (A Study on Electroless Ni-B Plating with DMAB as Reducing Agent. I. The Electrochemical Behavior of Precipitation Reaction on Austenite Stainless Steel Substrates)

  • 이창래;박해덕;강성군
    • 한국표면공학회지
    • /
    • 제32권2호
    • /
    • pp.172-181
    • /
    • 1999
  • The effect of the DMAB concentration, temperature, deposition time, and stabilizer concentration on the precipitation reaction of the electroless nickel plating using dimethylamine borane (DMAB) as reducing agent was investigated to by the weight gain and electrochemical method. The deposition rate was dependent with DMAB concentration. The polarization resistance of the precipitation reaction was reduced with DMAB concentration. The precipitation reaction rate of Ni-B deposits was controlled by the oxidation rate of DMAB as the source of electron. The boron content of the deposit was constant at about 5.5wt%, even when DMAB concentration in the solution was increased. The effect of temperature and stabilizer ($Pb(NO_3)_2$) concentration on deposition rate was shown to have co-dependent behaviors.

  • PDF

소금 농도가 김치 발효에 미치는 영향 (The effect of salt concentration on Kimchi fermentation)

  • 박우포;김재욱
    • Applied Biological Chemistry
    • /
    • 제34권3호
    • /
    • pp.295-297
    • /
    • 1991
  • Effect of salt concentration of brined Chinese cabbage on the Kimchi fermentation was investigated. The salt concentration range was 1-5% and chemical characteristics of pH, acidity and ascorbic acid were measured during fermentation at $25^{\circ}C$. Fermentation rate was also calculated from the $CO_2$ production. It was found that the higher salt concentration caused a significant decrease in the maximum value of fermentation rate and pH reduction. Ascorbic acid content was rapidly decreased initially, followed by increase to maximum and slowely decreased thereafter. This change was more apparent at higher salt concentration.

  • PDF

Effect of SDS on Retention of Nucleic Acid Components in High-Performance Liquid Chromatography

  • Kim Yong-Nam;Choi Kyeung-Soo;Lee Dai-Woon;Phyllis R. Brown
    • Bulletin of the Korean Chemical Society
    • /
    • 제13권3호
    • /
    • pp.240-245
    • /
    • 1992
  • The effect of the addition of sodium dodecyl sulfate (SDS) to a buffered mobile phase (pH 3.4) on the retention of nucleotides, nucleosides and bases was investigated with a polyvinyl alcohol (PVA) column. Depending on the concentration of SDS, two different trends in the retention of nucleosides and bases containing an $NH_2$ group were observed. If the concentration of SDS was less than 5.5 mM, the retention of compounds containing an $NH_2$ group increased as the concentration of SDS in the mobile phase increased. In contrast, if the concentration was greater than 5.5 mM, the retention of compounds containing an $NH_2$ group decreased. Thus, the SDS acted as an ion-pairing reagent at lower concentration but formed micelles at higher concentrations. The retention behavior of the nucleosides and bases in the presence of a micellar concentration of SDS in the mobile phase on the PVA column was compared to the retention behavior on other types of columns.

가토심근(家兎心筋) Mitochondria 분획내(分劃內) Adenosine triphosphatase 활성도(活性度)에 대(對)한 Diphenylhydantoin sodium 및 Quinidine의 작용(作用) (The Actions of Diphenylhydantoin sodium and Quinidine on the Adenosine triphosphatase Activity in Mitochondrial Fraction of Rabbit Heart)

  • 홍기환
    • 대한약리학회지
    • /
    • 제8권1호
    • /
    • pp.31-40
    • /
    • 1972
  • The author studied the actions of ouabain and diphenylhydantoin sodium on the ATPase activity in mitochondrial fraction isolated from rabbit heart and compared with that of quinidine. The results obtained are as follows: 1) In studying the $(Na^++K^+)-activated$ ATPase activity, the rabbit heart isolated was immediately frozen for 7-9 days (ageing of preparation) and thereafter the mitochondria1 fraction obtained by differential centrifugation technic was treated with solution A containing 0.15% deoxycholate for 24-48 hours at $-10^{\circ}C$ before using in experiment. These methods increased the activity ratio to 0.87-0.98. 2) The $(Na^++K^+)-activated$ ATPase activity in mitochondrial fraction of rabbit heart was not completely but markedly inhibited by ouabain. This inhibitory action of ouabain was moderately antagonised by $K^+$ concentration at constant Na concentration. 3) Diphenylhydantoin sodium in concentration of $5{\times}10^{-4}{\sim}10^{-3}M$ stimulated markedly not only $Mg^{++}-dependent$ ATPase activity but also $(Na^++K^+)$-activated ATPase activity and in concentration lower than $10^{-6}M$ had little effect. However, this effect of diphenylhydantoin was markedly increased in the presence of $Na^+$ alone rather than $K^+$ alone, but lesser than that effect in the presence of both $Na^+$ and $K^+$, together. The stimulating effect of diphenylhydantoin was specifically antagonized by ouabaion. 4) When the rabbits were intravenously injected with ouabain and diphenylhydantion respectively, $(Na^++K^+)-activated$ ATPase activity of rabbit heart of ouabain-treated group was much decreased and both $(Na^++K^+)-activated$ ATPase and $Mg^{++}-activated$ ATPase activity were moderately increased in diphenylhydantoin-treated rabbit group. 5) The $(Na^++K^+)-activated$ ATPase activity in mitochondrial fraction of rabbit heart was slightly inhibited by quinidine in high concentration of $10^{-4}M$, but nearly little effect was observed below the concentration of $5{\times}10^{-5}M$. 6) It might be possible to conclude that diphenylhydantoin specifically antagonised the action of ouabain on the membrane ATPase, which is different from the action of quinidine.

  • PDF

슬러지계면층높이변화모델에서 컬럼높이에 대한 영향 (The Effect of Column Height on Sludge-Water Interface Height Change Model)

  • 박석균;강선홍
    • 상하수도학회지
    • /
    • 제20권2호
    • /
    • pp.265-272
    • /
    • 2006
  • While sludge settles down in a column, sludge settling characteristic is influenced by effect parameters, interparticle force, wall effect etc. As the height of a column changes, the settling velocity of sludge-water interface changes, too. At lower sludge concentration, particular effect was not observed by the difference of column height, however it was observed that settleability of sludge was greatly influenced by column height when sludge settling was poor or sludge concentration was high. It is therefore required to consider the effect of column height when the power model for sludge interface settling is established. In the tests, there was hardly any $SVI_{ts}$(SVI after "t" minutes) difference in each column after 10min at $1.5kg/m^3$ of sludge concentration. When sludge concentration was at $2.5kg/m^3$, $SVI_{ts}$ tended to be constant after 20min. At $3.5kg/m^3$, $SVI_{ts}$ increased to 30minuets. The purpose of this work is to establish the correction factor that is able to compensate the errors derived from each different height of column.

Miconazole과 Amphotericin B의 항진균 활성에 대한 Anethole의 선택적 병용 효과 (Selective Combination Effect of Anethole to the Antifungal Activities of Miconazole and Amphotericin B)

  • 이상화;김창진
    • 약학회지
    • /
    • 제43권2호
    • /
    • pp.228-232
    • /
    • 1999
  • The combination effect of anethole with amphotericin B, fluconazole, miconazole, or 5-fluorocytosine was investigated against Saccharomyces cerevisiae. When combined with $\frac{1}{2}$ minimum inhibitory concentration (MIC) or $\frac{1}{2}$ minimum fungicidal concentration (MFC) of anethole, the antifungal activities of fluconazole and 5-fluorocytosine were not changed, but the fungistatic and the fungicidal activities of miconazole were increased 64-fold, respectively. In the case of amphotericin B, the fungistatic activity was increased 2-fold, while the fungicidal activity was decreased 2-fold. The combination effect of anethole with miconazole or amphotericin B was also investigated at the various concentrations using the macrobroth dilution checkerboard method. The fractional inhibitory concentration (FIC) and the fractional fungicidal concentration (FFC) index between B exhibited the FIC index of 8.25 and the FFC of 32.06, respectively. Thus, it is analyzed that the combination of anethole with miconazole or amphotericin B on the antifungal action shows synergism and antagonism, respectively.

  • PDF