• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.40-64
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• 2005

Much biochemical information on peroxiredoxins (Prxs) has been reported but a genuine physiological function for these proteins has not been established. We show here that two cytosolic yeast Prxs, cPrxI and II, exist in a variety of forms that differ in their structure and molecular weight (MW) and that they can act both as a peroxidase and as a molecular chaperone. The peroxidase function predominates in the lower MW proteins, whereas the chaperone function is more significant in the higher MW complexes. Oxidative stress and heat shock exposure of yeasts causesthe protein structures of cPrxI and II to shift from low MW species to high MW complexes. This triggers a peroxidase-to-chaperone functional switch. These in vivo changes are primarily guided by the active peroxidase site residue, $Cys^{47}$, which serves as an efficient $'H_2O_2-sensor'$ in the cells. The chaperone function of the proteins enhances yeast resistance to heat shock.

• Advances in aircraft and spacecraft science
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• v.6 no.6
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• pp.479-495
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• 2019

Periodic cellular core structures included in sandwich panels possess good stiffness while saving weight and only lately their potential to act as passive vibration filters is increasingly being studied. Classical homogeneous honeycombs show poor vibracoustic performance and only by varying certain geometrical features, a shift and/or variation in bandgap frequency range occurs. This work aims to investigate the vibration filtering properties of the AUXHEX "hybrid" core, which is a cellular structure containing cells of different shapes. Numerical simulations are carried out using two different approaches. The first technique used is the harmonic analysis with commercially available software, and the second one, which has been proved to be computationally more efficient, consists in the Wave Finite Element Method (WFEM), which still makes use of finite elements (FEM) packages, but instead of working with large models, it exploits the periodicity of the structure by analysing only the unit cell, thanks to the Floquet-Bloch theorem. Both techniques allow to produce graphs such as frequency response plots (FRF's) and dispersion curves, which are powerful tools used to identify the spectral bandgap signature of the considered structure. The hybrid cellular core pattern AUXHEX is analysed and results are discussed, focusing the investigation on the possible spectral bandgap signature heritage that a hybrid core experiences from their "parents" homogeneous cell cores.

• Journal of the Korean Magnetic Resonance Society
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• v.19 no.3
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• pp.112-118
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• 2015

Hsp31 protein is one of the members of DJ-1 superfamily proteins and has a dimeric structure of which molecular weight (MW) is 62 kDa. The mutation of DJ-1 is closely related to early onset of Parkinson's disease. Hsp31 displays $Zn^{+2}$-binding activity and was first reported to be a holding chaperone in E. coli. Its additional glyoxalase III active has recently been characterized. Moreover, an incubation at $60^{\circ}C$ induces Hsp31 protein to form a high MW oligomer (HMW) in vitro, which accomplishes an elevated holding chaperone activity. The NMR technique is elegant method to probe any local or global structural change of a protein in responses to environmental stresses (heat, pH, and metal). Although the presence of the backbone chemical shifts (bbCSs) is a prerequisite for detailed NMR analyses of the structural changes, general HSQC-based triple resonance experiments could not be used for 62 kDa Hsp31 protein. Here, we prepared the per-deuterated Hsp31 and performed the TROSY-based triple resonance experiments for the bbCSs assignment. Here, detailed processes of per-deuteration and the NMR experiments are described for other similar NMR approaches.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.2
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• pp.185-191
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• 2008

Optimal damping layout of the constrained viscoelastic damping layer on beam is identified with temperatures by using a gradient-based numerical search algorithm. An optimal design problem is defined in order to determine the constrained damping layer configuration. A finite element formulation is introduced to model the constrained layer damping beam. The four-parameter fractional derivative model and the Arrhenius shift factor are used to describe dynamic characteristics of viscoelastic material with respect to frequency and temperature. Frequency-dependent complex-valued eigenvalue problems are solved by using a simple re-substitution algorithm in order to obtain the loss factor of each mode and responses of the structure. The results of the numerical example show that the proposed method can reduce frequency responses of beam at peaks only by reconfiguring the layout of constrained damping layer within a limited weight constraint.

• The Journal of Korean Physical Therapy
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• v.27 no.2
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• pp.124-127
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• 2015

Purpose: The emphasis on gait rehabilitation after stroke depends on training support through the lower limbs, balance of body mass over the changing base of support. However, muscle weakness, lack of control of lower limb, and poor balance can interfere with training after stroke. For this case study report, a wearable robot orthosis was applied to stroke patients in order to verify its actual applicability on balance and gait ability in the clinical field. Methods: Two stroke patients participated in the training using the wearable robot orthosis. Wearable robot orthosis provides patient-initiated active assistance contraction during training. Training includes weight shift training, standing up and sitting down, ground walking, and stair up and down Training was applied a total of 20 times, five times a week for 4 weeks, for 30 minutes a day. Gait ability was determined by Stance phase symmetry profile, Swing phase symmetry profile, and velocity using the GAITRite system. Balance ability was measured using the Biodex balance system. Results: Subjects 1, 2 showed improved gait and balance ability with mean individual improvement of 72.4% for velocity, 19.4% for stance phase symmetry profile, 9.6% for swing phase symmetry profile, and 13.6% for balance ability. Conclusion: Training utilizing a wearable robot orthosis can be useful for improvement of the gait and balance ability of stroke patients.

• The Journal of Korean Physical Therapy
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• v.23 no.3
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• pp.43-47
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• 2011

Purpose: This study determined the best adjustable height supporter for stroke patients in wheelchairs for the maintenance of a symmetric sitting posture. Methods: Thirty-one stroke participants and 20 age-matched control participants were recruited. The enrolled participants were evaluated by the Force Sensitive Application (FSA) System that was used to assess weight shift and symmetry in wheelchair sitting and assess the symmetric index (SI) of subjects according to 1, 2 and 3 cm height supporters. Results: When a 1 cm height supporter was applied to the paretic side of stroke survivors, sitting postures of stroke patients were significantly more symmetrical (p<0.01). Cross tabulation between the SI of wheelchair sitting and that of the paretic side of stroke patients caused? by a 1 cm supporter showed that 21 SIs of 26 stroke patients were improved by a 1 cm supporter to the paretic side (k=0.26, p<0.01). Conclusion: The findings of the present study demonstrate that stroke patients can maintain a more symmetrical sitting posture (than is possible when simply sitting in a wheelchair seat) if a 1 cm supporter is applied to the paretic side of stroke patients.

• Journal of the Korean Regional Science Association
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• v.10 no.1
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• pp.39-52
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• 1994

This paper primarily aims to analyze the growth rate differentials of the economic activities in chung-Nam area. The research has been undertaken to find out the potentials of the economic activities and economic bases in the area. To analyze the economic potentials of the industries, the study employed the economic Growth Rate Differential Analysis by Henderson which is revised form of Shift-Share Analysis Methods. The research employed the employment data according to the standardized two-digit-classification-system during the period of 10 years from 1981 through 1991. The Growth Rate Differential Analysis calculates Total Growth Differentials which are dicomposed into two parts: Weight Part and Rate Part. Total Growth Differential can be calculated as the difference between national growth rate and regional growth rate by industry. The foundings are as follows: First, the economic bases of Chung-Nam area were found to be very weak, largely depending on primary industries such as agriculture and fisheries. Second, there was a great decline in urban industries in Tae Joeon, Cheon An and other cities over period of 1971-1981. It is strongly recommended that the planned items and products of each industrial complex must be reorgnized in a fashion to match those with high competitive power found in this research.

• Corrosion Science and Technology
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• v.3 no.6
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• pp.227-232
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• 2004

The carboxylates as a corrosion inhibitor has been studied by many researchers because of its environmental safety and low depletion rate. However, conventional test methods of inhibitor such as weight loss measurements, linear polarization resistance and corrosion potential monitoring etc., evaluate uniform corrosion of metals. These methods are unable to evaluate crevice-related corrosions, which are encountered in most of heat exchanging facilities. In order to choose the optimum corrosion inhibitor, the appropriate test methods are required to evaluate their performances in service environment. From this point of view, polarization technique was used to evaluate the characteristics of sodium heptanoate on corrosion behavior for carbon steel. Especially a thin film crevice sensor technique were applied to simulate the crevice corrosion in this study. From these experiments, we found that oxygen as an oxidizing agent was required to obtain stable passive film on the metal. Presence of oxygen, however, accelerated crevice corrosion. Potential shift by oxygen depletion and weakened inhibitive film inside the crevice were responsible for such accelerated feature. It is shown that film for corrosion inhibition is a mixture of sodium heptanoate and iron (II) heptanoate as reaction product of iron surface and sodium heptanoate. The iron (II) heptanoate which has been synthesized by reaction of heptanoic acid and ferrous chloride in methanol solution forms bidentate complex.

• The Journal of Korean Physical Therapy
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• v.16 no.3
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• pp.112-124
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• 2004

Purpose : The purpose of this study is to research the effects of the differences in shoe heel height on balanced performances with a balance master. Method : 40 healthy female adults were divided into 2 groups at random. All the female participants were tested by a balance master system. Differences were analyzed according to high heel shoes and low heel shoes. The ability of static postural balance control was measured by modified CTSIB and unilateral stance test, while that of dynamic postural balance control was measured by LOS (limit of stability) and rhythmic weight shift, among the programs of a balance master. Result : 1. There is no significant correlation between the ability of static and dynamic postural balance control before main test without the shoes. 2. Movement velocity and directional control ability were significant correlation compared result of in high heel shoes and low heel shoes group. Conclusion : In conclusion, the test results of the high heeled shoe group and the low heeled shoe group through a balance master system showed that the former one is inferior to the latter one.

• The Korean Journal of Emergency Medical Services
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• v.16 no.3
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• pp.103-115
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• 2012

Purpose : Inadequate chest compression during cardiopulmonary resuscitation(CPR) may result in the insufficient blood flow to preserve critical organ function. The study evaluated changes of quality of cardiopulmonary resuscitation over time in 30:2 CPR by laypersons and analyzed rescuer factors affecting the quality of chest compressions over time. Methods : This study was designed to know quality of CPR changes during 5 minutes. 47 students completed CPR training courses. They were performed 30:2 CPR using a manikin with Skill-Reporter for 5 minutes continuously to get data of depth, rate of chest compression, volume and correct rate of ventilation. Results : Time dependent analysis showed significant ineffective compression depth in females and under weight rescuers. In case of female, we found effective compression depth has maintained up to 2 minutes, but it decreased significantly after 2 minutes. However, underweight rescuers maintained effective compression depth up to a minute but it decreased after 1 minute. Conclusion : Although compression rate maintained over time, chest compression quality declined significantly. It suggested switching compression at an interval of 2 minutes is reasonable for 30:2 CPR by layperson but underweight rescuers may provide effective chest compression by switching shift every one minute.