• Fisheries and Aquatic Sciences
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• v.11 no.4
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• pp.224-228
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• 2008

With the aim of increasing the $CoQ_{10}$ production in mass culture, the effect of aeration-agitation on the $CoQ_{10}$ production using Rhodobactor sphaeroides was investigated in a l-L bioreactor. The maximum $CoQ_{10}$ production was 1.69 mg/g of dry cell weight under conditions of 50 Lux, $30^{\circ}C$, 300 rpm, and 5-vvm aeration. The $CoQ_{10}$ production was improved to produce 2.91 mg/g of dry cell weight under reduced conditions of agitation speed (200 rpm) and aeration rate (0.2 vvm). When R. sphaeroides was cultivated under more reduced DO levels during the exponential phase of the cell, the $CoQ_{10}$ production yield of 3.88-mg/g dry cell weight was the maximum obtained. Therefore, poorer conditions of aeration-agitation resulted in higher production of $CoQ_{10}$, and thus DO content was a crucial factor in the production of $CoQ_{10}$. Accordingly, it was necessary to control the DO concentration in order to enhance the $CoQ_{10}$ biosynthesis within a large-scale production.

• Journal of Environmental Science International
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• v.10 no.1
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• pp.65-71
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• 2001

HRP(high rate pond) which had kept the manufactured clay of 3cm-thickness as benthic clay in reactor and the 6 flat-blade turbine as impeller for agitation was named HRASP(high rate algae stabilization pond). And the experiment for treatment of artificial synthesis wastewater containing COD :300mg/$\ell$, NH$_3$-N : 300mg/$\ell$, T-P : 9mg/$\ell$ as nutrients was been performed successfully. This reactor was been operated under conditions : 24hrs.-irradiation and water temperature, $25^{\circ}C$ and pH 7 and agitation velocity, 15, 30, 45rpm and the effect of agitation velocity on algal bioaccumulation of nutrients was been studied with view point of fluid dynamics. The next followings could be obtained as results. 1. The agitation with a turbine impeller blade in HRASP makes clay particle indicate superior suspension effect by means of forming of excellent curl/shear flow in reactor. 2. The excessive suspension of clay particle which is created at 45rpm as rotation velocity of impeller blade of turbine disturbs the light penetration and algal photosynthesis reaction. 3. Efficiencies for removal of nutrients come out as COD : 93.9%~94.3%, ($NH_3-N + NO_3-N$) : 81.9%~99.0%, T-P : 46.8%~53.6%. 4. Kuo values of $K_1$for algal growth come out seperately as 15rpm : $1.876{\times}10^{-2}, 30rpm : 4.618{\times}10^{-3}$. 5. Kuo values of $K_2$for removal of N, P come out seperately as 15rpm : $8.403{\times}10^{-1}$ and $1.397{\times}10^{-1}$, 30rpm : $4.823{\times}10^{-1} and 2.052{\times}10^{-1}$. 6. It can be guessed easily that the excessive agitation can inhibit the algal and bacterial symbiotic reaction if it is considered that micro organism\` sense to preservation of life is relied on natural function of metabolism. Therefore the studies for this matter should be followed continuously.

• Journal of Korean Academy of Nursing
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• v.30 no.4
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• pp.825-835
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• 2000

The agitation of dementia patient is a factor which aggravates the care-givers' burdon, and it is needed to develop intervention methods. Hall and Buckwalter hypothesized that an increase in agitation behavior occur when persons experience high levels of stress. This study was conducted to explore the efficacy of hand massage in producing relaxation and decreasing agitation behaviors in persons with dementia. Hand massage was administered once a day in afternoon for 8days to 24 patients and 4days to 23 patients. There was no difference in result between the two groups. Significant differences were found in systolic blood pressure, pulse rate, emotional state from pre to post -intervention with the use of hand massage. The change of systolic blood pressure was 26% explained by ADL, MMSE-K and institutionalized period. The most significant variable was institutionalized period. The change of diastolic blood pressure was 11% explained by ADL, and it was significant. But no decrease in agitation behavior was observed and no increase in functional capacity.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.382-385
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• 2001

The effect of agitation speed on the production of mycelial growth and exo-biopolymer in bioreaetor culture was investigated. The maximum production of mycelia and exo-biopolymer was obtained at 350 rpm, where the maximum concentrations of mycelial growth and exo-biopolymer were 62 g/L and 23 g/L, respectively. The effect of agitation speed on the hyphal length and the number of tips was examined. The hyphal length and the number of tips of Cordyceps sinensis 16 in bioreaetor culture at 350 rpm were increased up to 660 ${\mu}m$ and 14/ml, respectively.

• Korean Journal of Adult Nursing
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• v.27 no.1
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• pp.106-116
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• 2015

Purpose: The purpose of this review was to assess the quality and to evaluate the effectiveness of music interventions in reducing agitation in older adults with dementia. Methods: Randomized controlled studies and randomized crossover studies were identified by searching MEDLINE, EMBASE, CINAHL, PsycINFO, AGELINE, Cochrane Central Register of Controlled Trials, Korea Med, Kmbase, RISS, National Assembly Digital Library, KISS, and RICH. Two reviewers independently retrieved articles, extracted data, and assessed the quality of studies. Results: In total, 10 studies were selected from 1095 unique citations. All included studies were conducted in long term care settings. Overall, risk of bias for included studies was low to moderate. The weighted average effect size across studies was -0.39 (95%CI [-0.69, -0.10], p=.009, $I^2=63%$). Music therapy was effective to reduce agitation of the older adults with dementia. Conclusion: Music intervention can be an effective non-pharmacological intervention for the reduction of agitation in dementia. Future studies need to use rigorous research method and to provide description of research methods in greater detail. In addition, future studies are required to explore the effects of music therapy according to severity of agitation and dementia.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.192-195
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• 2002

Effect of aeration rate and agitation speed on cell growth and the production of heteropolysaccharide-7 (PS-7) by Beijerinckia indica was investigated. Aeration rate and agitation speed in a 7L bioreactor ranged from 0.5 to 1.5 vvm and from 300 to 500 rpm, respectively. Higher agitation speed with an aeration rate of 0.5 vvm in the bioreactor resulted in maintenance of higher concentration of dissolved oxygen in the medium, which enhanced the production of PS-7. In this study with a 7L bioreactor, maximal production of PS-7 was 11.0 g/L and its conversion rate from 2% (w/v) glucose was 0.55 when the aeration rate and agitation speed were 1.0 vvm and 500 rpm, respectively. Proper aeration rate and agitation speed might enhance the production of PS-7 as well as reduce the time to reach maximal production.

• Resources Recycling
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• v.27 no.1
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• pp.45-54
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• 2018

This study aimed to investigate the effects of mechanical factors such as agitation speed and air rate in fly ash flotation. Specifically, we used thermal power plant fly ash with unburned carbon content of 3.4 to 3.7%. The effect of pH, agitation speed, collector dosage, and frother dosage - the key factors of froth flotation - showed unburned carbon recovery and unburned carbon content of 63% and 34%, respectively, when the dosage of safflower oil used as collector was 800 g/ton, pH was 7, agitation speed was 1,200 rpm, and frother dosage was 400 g/ton. The SEM/EDS analysis of fly ash in that case indicated that the spherical fly ash particles lowered the unburned carbon content as they floated with the air bubbles without being dissolved in the unburned carbon or settled in the ore solution. The other experiment of changing the mechanical factors such as agitation speed and air rate resulted in unburned carbon recovery and unburned carbon content of 74% and 67%, respectively, at air rate of 8 L/min and agitation speed of 900 rpm. The recovery and unburned carbon content increased as the low agitation speed and additional air injection decreased the strength of the eddy current in the ore solution and consequently prevented the floating of fine fly ash particles with unburned carbon. In addition, the recovery rate and unburned carbon increased further to 80% and 70%, respectively, showing the best performance when the agitation speed and air rate were lowered to 800 rpm and 6 L/min, respectively.

• KSBB Journal
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• v.16 no.3
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• pp.307-313
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• 2001

The effects of agitaion and aeration on mycelial growth, exo-polysaccharide (EPS) production, and substrate consumption upon the submerged cultivation of G. lucidum were investigated, and the batch kinetics of the EPS fermentation of G. lucidum were interpreted as function of agitation speed and aeration rate. In a 2.6 L jar fermenter system, the optimum agitation speed and aeration rate for EPS production were determined to be 400 rpm and 1.0 vvm, respectively. The maximum production of EPS obtained was 15 g/L. The logistic model for mycelial growth fitted the experimental data better than that determined by the Monod and the two-thirds power models. The Luedeking-Piret equation adequately modelled the kinetic data obtained for product and substrate.

• Journal of the Korean Chemical Society
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• v.17 no.3
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• pp.213-223
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• 1973

This report has been focused on the studies of the hydraulic pressure distribution which is created by the agitation of the both liquids, dialysing solution and solvent, on either side of the dialysis membrane surface. Agitators of the both liquids have been investigated and developed which can counterbalance the hydraulic pressures. The effects of the agitation velocities on the dialysing velocity have been studied under the conditions which allow the uniform dialysis on the whole surface of the dialysis membrane. Each agitation velocity of the dialysing solution and solvent, at which the dialysis coefficient is obtained most precisely, has been determined.

• Food Science of Animal Resources
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• v.20 no.2
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• pp.107-113
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• 2000

This study was carried out to investigate the effects of temperature activation and agitation on lipolysis of goat milk. When goat milk was temperature activated twice at intervals of 12hours, free fatty acids were significantly increased after the first activation, but increased slightly during the re-cooling period and after the second activation. Lipolysis of the goat milk warmed at $30^{\circ}C$ was significantly facilitated during the re-cooling period. Lipolysis of the goat milk warmed at $30^{\circ}C$ was much higher than those warmed at $10^{\circ}C$ and $40^{\circ}C$ respectively. The highest lipolysis was occurred when the goat milk was warmed at $30^{\circ}C$ for 5 minutes after pre-cooling for 24 hours at $40^{\circ}C$. However, any significant difference was not found in the milk warmed at $40^{\circ}C$, regardless of the pre-cooling period. Lipolysis of the goat milk warmed and agitated at $30^{\circ}C$ was significantly facilitated during the re-cooling period. The lipolysis of that at $30^{\circ}C$ was significantly facilitated during the re-cooling period. The lipolysis of that at $30^{\circ}C$ was much enhanced with agitation. The lipolysis was much higher when agitated at $30^{\circ}C$ than when agitated at $10^{\circ}C$. The length of agitation time at $30^{\circ}C$ didn't give any effect on lipolysis.