• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1628-1634
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• 2009

Small heat shock proteins (sHSPs) function as molecular chaperones that protect cells against environmental stresses. In the present study, the genes of hsp17.6 and hsp17.7, cytosolic class I sHSPs, were cloned from a tropical plant, Ageratina adenophorum. Their C-terminal domains were highly conserved with those of sHSPs from other plants, indicating the importance of the C-terminal domains for the structure and activity of sHSPs. The recombinant HSP17.6 and HSP17.7 were applied to determine their chaperone function. In vitro, HSP17.6 and HSP17.7 actively participated in the refolding of the model substrate citrate synthase (CS) and effectively prevented the thermal aggregation of CS at $45^{\circ}C$ and the irreversible inactivation of CS at $38^{\circ}C$ at stoichiometric levels. The prior presence of HSP17.7 was assumed to suppress the thermal aggregation of the model substrate CS. Therefore, this report confirms the chaperone activity of HSP17.6 and HSP17.7 and their potential as a protectant for active proteins.

• Journal of Radiation Protection and Research
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• v.20 no.2
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• pp.71-78
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• 1995

To develop methods to reduce radiation risk and apply such knowledge to improvement of radiation protection, the effects of cobaltous chloride known as bioantimutagen on the function of E. coli RecA protein involved in the repair of DNA damage were examined. The results demonstrated two distinct effects of cobaltous chloride on the RecA protein function necessary for the strand exchange reaction. Cobaltous chloride enhanced the ability of RecA protein to displace SSB protein from single-stranded DNA and the duplex DNA-dependent ATPase activity. RecA protein was preferentially bound with UV-irradiated supercoiled DNA as compared with nonirradiated DNA The binding of RecA protein to UV-irradiated supercoiled DNA was enhanced in a dose-dependent manner. It is likely that studies on the factors affecting repair efficiency and the DNA repair proteins may provide information on the repair of ionizing radiation-induced DNA damage and the mechanism for DNA radioprotection.

• Journal of IKEEE
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• v.24 no.1
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• pp.132-139
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• 2020

The ionizer module used in this air cleaner supplies high voltages of 3.5KV / -4KV to the discharge electrode HV+ / HV- using a winding transformer to generate positive and negative ions by electric field radiation of carbon fiber brush. The ionizer module circuit using the existing MCU has the disadvantage of large PCB size and expensive price, and the gate driver chip using the existing ring oscillator has oscillation period sensitive to PVT (Process-Voltage-Temperature) fluctuation and there is risk of fire or electric shock because there is no fault detection function by short circuit of HV+ and GND as well as HV- and GND. Therefore, in this paper, even though PVT fluctuates, by using 7-bit binary up counter, HV+ voltage reaches the target voltage by adjusting oscillation period. And an HV+ short fault detection circuit for detecting a short circuit between HV+ and GND, an HV- short fault detection circuit for detecting a short circuit between HV- and GND, and an OVP (Over-Voltage Protection) for detecting that HV+ rises above an overvoltage are newly proposed.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.4
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• pp.281-296
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• 2021

The beneficial effects of hypoxic preconditioning are abolished in the diabetes. The present study was designed to investigate the protective effects and mechanisms of repeated episodes of whole body hypoxic preconditioning (WBHP) in db/db mice. The protective effects of preconditioning were explored on diabetes-induced vascular dysfunction, cognitive impairment and ischemia-reperfusion (IR)-induced increase in myocardial injury. Sixteen-week old db/db (diabetic) and C57BL/6 (non-diabetic) mice were employed. There was a significant impairment in cognitive function (Morris Water Maze test), endothelial function (acetylcholine-induced relaxation in aortic rings) and a significant increase in IR-induced heart injury (Langendorff apparatus) in db/db mice. WBHP stimulus was given by exposing mice to four alternate cycles of low (8%) and normal air O₂ for 10 min each. A single episode of WBHP failed to produce protection; however, two and three episodes of WBHP significantly produced beneficial effects on the heart, brain and blood vessels. There was a significant increase in the levels of brain-derived neurotrophic factor (BDNF) and nitric oxide (NO) in response to 3 episodes of WBHP. Moreover, pretreatment with the BDNF receptor, TrkB antagonist (ANA-12) and NO synthase inhibitor (L-NAME) attenuated the protective effects imparted by three episodes of WBHP. These pharmacological agents abolished WBHP-induced restoration of p-GSK-3β/GSK-3β ratio and Nrf2 levels in IR-subjected hearts. It is concluded that repeated episodes of WHBP attenuate cognitive impairment, vascular dysfunction and enhancement in IR-induced myocardial injury in diabetic mice be due to increase in NO and BDNF levels that may eventually activate GSK-3β and Nrf2 signaling pathway to confer protection.

• Smart Structures and Systems
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• v.31 no.4
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• pp.421-436
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• 2023

This paper presents a vibration displacement measurement and damage identification method for a space truss structure from its vibration videos. Features from Accelerated Segment Test (FAST) algorithm is combined with adaptive threshold strategy to detect the feature points of high quality within the Region of Interest (ROI), around each node of the truss structure. Then these points are tracked by Kanade-Lucas-Tomasi (KLT) algorithm along the video frame sequences to obtain the vibration displacement time histories. For some cases with the image plane not parallel to the truss structural plane, the scale factors cannot be applied directly. Therefore, these videos are processed with homography transformation. After scale factor adaptation, tracking results are expressed in physical units and compared with ground truth data. The main operational frequencies and the corresponding mode shapes are identified by using Subspace Stochastic Identification (SSI) from the obtained vibration displacement responses and compared with ground truth data. Structural damages are quantified by elemental stiffness reductions. A Bayesian inference-based objective function is constructed based on natural frequencies to identify the damage by model updating. The Success-History based Adaptive Differential Evolution with Linear Population Size Reduction (L-SHADE) is applied to minimise the objective function by tuning the damage parameter of each element. The locations and severities of damage in each case are then identified. The accuracy and effectiveness are verified by comparison of the identified results with the ground truth data.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.7
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• pp.668-673
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• 2011

This paper presents design and control of a wheelchair robot for handicapped or elderly persons. Novel multi-functional design concepts are introduced. The first function is to balance the chair always parallel to the flat ground so that the driver feels comfortable when he/she drives on the slope. The second function is to help the driver to stand up by pushing the chair so that the driver can get out from the chair with ease. The third design is to make it foldable for easy carrying for automobiles. The last function is an immediate stop and start protection. Experimental studies are conducted to demonstrate the feasibility and functionality of each mechanical design.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.11
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• pp.647-654
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• 2003

As electrical power system has become complicated and enlarged to cope with the increasing electric demand, it has to be expected that higher speed, higher reliability, higher function and higher arithmetic ability in protective relay should be realized. Therefore, in this papers, by hardware design and implementation used DMA controller that transfer blocks of data to any location in the memory map without interfering with CPU operation, CPU utilization is increased effectively, as a result it made possible to implement multi-function digital protective relay which has high trust and high function of protection as well as control and metering for power transformers using single processor(DSP).

• Korean Journal of Oriental Medicine
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• v.12 no.1
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• pp.91-102
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• 2006

We treated KunYangDan (KYK) in SD rats in order toexamine the protective effect against cell damage induced by diethylhexyl phthalate (DEHP). KYD reduced DEHP toxicity by increasing the function of immune cell numbers weight increase of spleen.red blood cells,HB,and HCT content,sperm number and mobility,resulting in improving reproductive function by judging from the recovery of testosterone content. Interestingly the hormone change of testosterone by KYD significantly recovered the decreased its leve. Taken together,these results suggest that KYD specifically affect the reproductive function induced by DEHP,an endocrine disruptor.

• Journal of the Korean Society of Physical Medicine
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• v.2 no.1
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• pp.65-72
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• 2007

Purpose : The purpose of this study is a research on the evaluation about shoulder joint function. Methods : It's based on the reference books. Result : Shoulder joint has the biggest ROM in human body, and it is a joint that stability and mobility are required at the same time sport art. Especially, function of shoulder joint than other what item players of more important overhead item correct diagnosis and evaluation for shoulder joint injury require. Measurement equipment for shoulder joint is helping a lot of incorrect diagnosis and analysis about shoulder joint function of overhead players through a lot of developments. Conclusion : I think a lot of helps torture in motor ability elevation of players and player protection as analysis by special quality in item of overhead players.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.11
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• pp.75-80
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• 2012

In this paper, the operational characteristics due to the introduction of the superconducting fault current limiter(SFCL) with a peak current limiting function were analyzed in the power distribution system. The parallel structure of the superconducting element can operate the peak current limiting function depending on the transient amplitude of fault current. We studied the operating characteristics of the introduction of the SFCL with a peak current limiting function in the power distribution system. Furthermore, we were analyzed between the SFCL with a peak current limiting function and the protection devices in the power distribution system, through the short circuit experiments.