• Korean Journal of Microbiology
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• v.44 no.2
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• pp.93-97
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• 2008

RraA is a recently discovered protein inhibitor that regulates the enzymatic activity of RNase E, which plays a major role in the decay and processing of RNAs in Escherichia coli. It has also been shown to regulate the activity of RNase ES, a functional Streptomyces coelicolor ortholog of RNase E, which has 36% identity to the amino-terminal region of RNase E. There are two open reading frames in S. coelicolor genome that can potentially encode proteins having more than 35.4% similarity to the amino acid sequence of RraA. DNA fragment encoding one of these RraA orthologs, designated as RraAS2 here, was amplified and cloned in to E. coli vector to test whether it has ability to regulate RNase E activity in E. coli cells. Co-expression of RraAS2 partially rescued E. coli cells over-producing RNase E from growth arrest, although not as efficiently as RraA, induced by the increased ribonucleolytic activity in the cells. The copy number of ColEl-type plasmid in these cells was also decreased by 14% compared to that in cells over-producing RNase E only, indicating the ability of RraAS2 to inhibit RNase E action on RNA I. We observed that the expression level of RraAS2 was lower than that of RraA by 4.2 folds under the same culture condition, suggesting that because of inefficient expression of RraAS2 in E. coli cells, co-expression of RraAS2 was not efficiently able to inhibit RNase E activity to the level for proper processing and decay of all RNA species that is required to restore normal cellular growth to the cells over-producing RNase E.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.243-248
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• 2016

RNase E (Rne) is an essential enzyme involved in the processing and degradation of a large portion of RNAs in Escherichia coli. The enzymatic activity of RNase E is controlled by regulators of ribonuclease activity, namely, RraA and RraB. Gram-positive bacterium Streptomyces coelicolor also contains homologs of Rne and RraA, designated as RNase ES (Rns), RraAS1, and RraAS2. In the present study, we investigated the effect of S. coelicolor RraAS1 on the ribonucleolytic activity of RNase E in E. coli. Coexpression of RraAS1 with Rne resulted in the decreased levels of rpsO, ftsZ, and rnhB mRNAs, which are RNase E substrates, and augmented the toxic effect of Rne overexpression on cell growth. These in vivo effects appeared to be induced by the binding of RraAS1 to Rne, as indicated by the results of co-immunoprecipitation analysis. These results suggested that RraAS1 induces ribonucleolytic activity of RNase E in E. coli.

• Korean Journal of Community Nutrition
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• v.2 no.2
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• pp.179-186
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• 1997

A new bioelectrical impedance method has been developed and evaluated. The electrodes; were made of stainless steel and electrical interfaces were created by an upright subject gripping hand electrodes and stepping onto foot electrodes. Eight tactile electrodes were in contact with surfaces of both hands and feet; thumb, palm and fingers, front sole, and rear sole. Automatic on-off switches were used to change current pathways and to measure voltage differences for target segments. Segmental body resistances and whole body resistance(RWHOLE)were measured in 60 healthy subjects. Segmental resistances of right arm(RRA), left arm(RLA), trunk(RT), right leg(RRL) and left leg(RLL)were310.0$\pm$61.6$\Omega$, 316.9$\pm$64.6$\Omega$, 25.1$\pm$3.4$\Omega$, 236.8$\pm$31.2$\Omega$ and 237.6$\pm$30.4$\Omega$, respectively. Individual segmental impedance indexes(Ht2/RRA, Ht2/RT, and Ht2 /RLA) were closely related to lean body mass(LBM)as measured by densitometry ranged from r=0.925 to 0.960. Ht2/(RRA+RT+RLA) predicted LBM slightly better(r=0.969) than the traditional index, Ht2/RWHOLE(r=0.964), supporting the accuracy of the segmental measurement. A multiple regression equation utilizing Ht2/RRA, Ht2/RT and Ht2/RRL predicted LBM with r=0.971. Ht2/RRA term of the regression contributed to more than 40$\%$ of the LBM prediction, indicating that lean mass of arm represented whole body LBM more closely than other body segments. The new bioimpedance method was characterized by upright posture, eight tactile electrodes, segmental measurements and utilization of electronic switches in comparison with the traditional method. The measurement with this new method was extremely reproducible, quick and easy to use.

• Composites Research
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• v.36 no.5
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• pp.349-354
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• 2023

Poly(3-hexylthiophene) (P3HT) is a conjugated polymer that is highly soluble in organic solvents and is readily available. However, its electrical properties as an active channel in electronic devices are not enough for practical applications, necessitating further improvement in the properties. In this study, we demonstrate that the blending of two P3HT polymers (i.e., regio-regular (RR) P3HT and regio-random (RRa) P3HT) with different regioregularities can significantly improve charge transport characteristics of the blend films. The morphological and electrical properties of the blend films were systematically investigated by varying the ratio between two P3HT polymers. Atomic force microscopy (AFM), X-ray diffraction (XRD), and UV-visible absorption spectroscopy (UV-vis) were employed to evaluate the morphological and optoelectronic properties of the blend films. The crystallinity of the blend films increased with increasing the content of RRa-P3HT to 20 wt% and gradually decreased as the content increased to 80%. Consistently, the highest charge carrier mobility was obtained from the blend films containing 20 wt% RRa-P3HT, which value was measured to be 0.029 cm²/V·s. The values gradually decreased to 0.0007 cm²/V·s with increasing the content of RRa-P3HT to 80 wt%.

• Journal of the Ergonomics Society of Korea
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• v.25 no.2
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• pp.197-204
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• 2006

The purpose of this study was to investigate the relationship between the cumulative fatigue of trunk muscles and the period of recovery time during repetitive lifting and lowering task with two different frequencies(4 times/min and 6 times/ min). Eight healthy males with no prior history of LBD(low back disorders) volunteered for this study. Subjects had 2, 3, 4, and 5 minutes recovery time respectively while they were preforming the lifting and lowering task at 15% level of MVC. EMG signals from six trunk muscles were collected and the fatigue level was analyzed quantitatively. In results, the fatigue levels of LES(left elector spinae), RLD(right lattissimus dorsi), LLD(left lattissimus dorsi), RRA(right rectus abdominis) and LRA(left rectus abdominis) were recovered when 3 minutes recovery time was given at 4 times/min frequency. However, the fatgue level of RES(right elector spinae) was recovered when 4 minutes recovery was given. On the other hand, when 6 times/min frequency was used, the RLD, LLD, RRA and LRA were recovered at 5 minutes of recovery time. But for RES and LES, it took longer than 5 minutes to be recovered. This results can be applied to design the adequate length of recovery time to control the cumulative fatigue of trunk muscles in industry with repetitive lifting and lowering task.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6443-6447
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• 2014

Background: To determine the predictive value of the baseline stimulated thyroglobulin (STg) level for ablation outcome in patients undergoing adjuvant remnant radioiodine ablation (RRA) for differentiated thyroid carcinoma (DTC). Materials and Methods: This retrospective study accrued 64 patients (23 male and 41 female; mean age of $40{\pm}14$ years) who had total thyroidectomy followed by RRA for DTC from January 2012 till April 2014. Patients with positive anti-Tg antibodies and distant metastasis on post-ablative whole body iodine scans (TWBIS) were excluded. Baseline STg was used to predict successful ablation (follow-up STg <2 ng/ml, negative diagnostic WBIS and negative ultrasound neck) at 7-12 months follow-up. Results: Overall, successful ablation was noted in 37 (58%) patients while ablation failed in 27 (42%). Using the ROC curve, a cut-off level of baseline STg level of ${\leq}14.5ng/ml$ was found to be most sensitive and specific for predicting successful ablation. Successful ablation was thus noted in 25/28 (89%) of patients with baseline STg ${\leq}14.5ng/ml$ and 12/36 (33%) patients with baseline STg >14.5 ng/ml ((p value <0.05). Age >40 years, female gender, PTS >2 cm, papillary histopathology, positive cervical nodes and positive TWBIS were significant predictors of ablation failure. Conclusions: We conclude that in patients with total thyroidectomy followed by I-131 ablation for DTC, the baseline STg level is a good predictor of successful ablation based on a stringent triple negative criteria (i.e. follow-up STg < 2 ng/ml, a negative DWBIS and a negative US neck).

• Journal of information and communication convergence engineering
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• v.15 no.3
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• pp.143-150
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• 2017

Absorption of microwave radio frequency signal by atmospheric rain is prevalent at frequencies above 10 GHz. This paper presents the studies on rain attenuation at 18 GHz for 3.2 km experimental link between Khumdang (Korea Telecom, KT station) and Icheon (National Radio Research Agency, RRA station). The received signal data for rain attenuation and rain rate were collected at 10 second intervals over a three year periods from 2013 to 2015. Out of several models, the paper present discussion and comparison of ITU-R P.530-16 model, Moupfouma model, Da Silva Mello model along with suitable rain attenuation prediction method. The limitation of research lies on the experimental system that is set up in only one location, however, the preliminary results indicate the application of suitable 1-minute rain attenuation model for specific site. The method provides useful information for microwave engineers and researchers in making decision over the choice of most suitable rain attenuation prediction in terrestrial links.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.577-580
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• 2012

RRA Notification No.2010-36 suggests the 3-point method(fall-of-Potential) using 2 auxiliary poles only as a test method of earth resistance. However this method needs to much space to install auxiliary poles so it is very difficult to measure the earth resistance in spots such as a mountain district, rocky district. So, we have analyzed the methods of 2-point method and loop resistance method in IEEE std. 81 and ITU-handbook(Earthing and Bonding) and applied these methods in test bed with 3-point method. In this paper we have compared and analyzed the earth resistance value using these 3 methods.

• Archives of Orthopedic and Sports Physical Therapy
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• v.14 no.2
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• pp.55-64
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• 2018

Purpose : The purpose of this study was to investigate the effect of the sprinter and skater combined patterns on muscle contraction onset time and muscle activation of body stabilizing muscles. Method : Our study included young and healthy men in their 20s. The participants used the sprinter and skater combined patterns of the proprioceptive neuromuscular facilitation (PNF) methods to measure muscle activation and muscle contraction onset time of the trunk muscles. To measure muscle contraction onset time and muscle activation, electrodes were attached to the rectus abdominis (RA), external oblique (EO), internal oblique (IO), and erector spinalis (ES) regions. Significant differences were identified using a paired t-test and a one-way analysis of variance (ANOVA) analysis. Result : In the sprinter combined pattern, the muscle with the fastest onset time of contraction was the RES, and that with the slowest was the RRA (p<.001). In the skater combined pattern, the muscle with the fastest onset time of contraction was the LES, and that with the slowest was the LRA (p<.001). In the sprinter combined pattern, the REO and LIO presented medium muscle contraction onset times (p<.001). In the skater combined pattern, the LEO and RIO presented medium muscle contraction onset times (p<.001). Conclusions: Based on these results, these patterns could be used as exercise methods for the elderly with delayed proactive response speeds of the body stabilization methods due to imbalances in body stabilizing muscles or limbs movement.

• The Korean Journal of Nuclear Medicine Technology
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• v.19 no.2
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• pp.102-107
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• 2015

Purpose Serum Thyroglobulin measurement is a major tool for the follow-up of differentiated thyroid cancer (DTC) patients. Thyroglobulin is Normal thyroid tissue, or thyroid cancer tissue produced only. Thyroid hormone to a halt without Tg differentiation of thyroid cancer recurrence just by measuring how to decide whether there was increasing expectations if I can do it instead. Therefore, in excellent sensitivity Tg new inspection of the functional sensitivity by measuring the looked to evaluate the usefulness of reagents. Thyroidectomy is measuring the numbers Tg (total thyroidectomy) remaining thyroid ablation and radioactive iodine (radioactive iodine remnant ablation, RRA) DTC in patients being diagnosed with or help predict the remaining early detection of thyroid cancer recurrence. Materials and Methods Agent that I'm currently using Tg of the measurements of low clinical specimen for a second drainage of the three (0.08 0.17, 0.98, ng/mL) within the scope of the dilute magnification (2, 4, 8, 16, 32 times) by dilute Intraassy (n=10) and Interassay (n=10) out in no time. Concentration value according to the coefficient of variation and the mean and standard deviation of each measurement (Coefficient of variation, CV) the absolute value of the measured values that corresponds to 20 percent target a coefficient of variation of CV Find the value of the concentration of the functional sensitivity measurement did. Also, analytical sensitivity with recovery rates, Dilution test inspections, and interrelationship, compared. Results Sensitivity is an excellent analytical sensitivity within the prosecutor kit Tg 0.006 ng/mL, and core analytical sensitivity, conducted by the 0.006 ng/mL to same conclusion. Be rather high to 142 percent recovery rate was 60 to measurement and functional sensitivity, 0.01766 ng/mL(Intraassay n=10) was measured at. CBC is relatively good correlation as ($R^2=0.949$) the correlation. Conclusion Recently ultrasensitive thyroglobulin this clinically important indicators of the previous kit and demands are lower than sensitivity to the measurement results. Therefore, ultrasensitive thyroglobulin test is correlated that there would be useful in value in nuclear medicine the thyroid gland.