• The Korean Journal of Physiology and Pharmacology
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• v.15 no.6
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• pp.415-422
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• 2011

Previously, we reported that besides retinal ganglion cell (RGC) spike, there is ~10 Hz oscillatory rhythmic activity in local field potential (LFP) in retinal degeneration model, rd1 mice. The more recently identified rd10 mice have a later onset and slower rate of photoreceptor degeneration than the rd1 mice, providing more therapeutic potential. In this study, before adapting rd10 mice as a new animal model for our electrical stimulation study, we investigated electrical characteristics of rd10 mice. From the raw waveform of recording using $8{\times}8$ microelectrode array (MEA) from in vitro-whole mount retina, RGC spikes and LFP were isolated by using different filter setting. Fourier transform was performed for detection of frequency of bursting RGC spikes and oscillatory field potential (OFP). In rd1 mice, ~10 Hz rhythmic burst of spontaneous RGC spikes is always phase-locked with the OFP and this phase-locking property is preserved regardless of postnatal ages. However, in rd10 mice, there is a strong phase-locking tendency between the spectral peak of bursting RGC spikes (~5 Hz) and the first peak of OFP (~5 Hz) across different age groups. But this phase-locking property is not robust as in rd1 retina, but maintains for a few seconds. Since rd1 and rd10 retina show phase-locking property at different frequency (~10 Hz vs. ~5 Hz), we expect different response patterns to electrical stimulus between rd1 and rd10 retina. Therefore, to extract optimal stimulation parameters in rd10 retina, first we might define selection criteria for responding rd10 ganglion cells to electrical stimulus.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.10B
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• pp.1470-1474
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• 2001

8B/10B 선로부호를 채택한 기가비트 이더넷 PCS 수신측에서는 동기부의 바이트 동기획득과 수신부의 디코딩을 위해 Running Disparity(RD) 에러인 데이터열을 검출해야 한다. 기존의 RD 에러 검출 방법은 직렬 입력 비트에서 RD 에러를 검출하였으나 제안하는 RD 에러 검출 방법은 125MHz 속도의 10비트 데이터열을 받아 4비트열과 6비트열로 나누어 바이트 클럭에 따라 RD를 계산하고 계산된 이전의 RD값과 현재의 RD값을 비교하며 RD 위반 에러 데이터를 검출한다. 이는 기존의 RD 에러 검출 방법이 비트 클럭과 니블 클럭에 따라 RD 에러를 검출하기 때문에 야기되는 초고속 처리에 대한 한계를 해결한 것이며 기가비트 이더넷에 적합한 새로운 RD 에러 검출 방법이다.

• KEPCO Journal on Electric Power and Energy
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• v.3 no.1
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• pp.57-63
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• 2017

This study aimed at proposing a RD&D good practice policy guidelines for energy technology innovation in electric power industry, we identified the success factors on energy RD&D through representative case analysis such as energy RD&D demonstration project and strategy plan, technology road map, etc. Based on a successful case study, we have identified the key elements needed to suggest when setting a RD&D technology innovation policy framework for technological competitiveness in the power industry sector. We have presented guidelines for energy technology innovation direction from the full cycle perspective of RD&D. The energy RD&D innovation system that we have established is meaningful in that the implications are derived and reflected through the case analysis of developed countries. The results of this study are as follows; Enhancement of R&D investment performance, commercialization of research achievements, promotion of export industrialization of electric power industry, establishment of RD&D governance system of power energy, etc.

• Korean Journal of Pharmacognosy
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• v.51 no.4
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• pp.340-348
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• 2020

This study was conducted to evaluate the immunomodulatory effects of red doraji (Platycodon grandiflorum, RD) prepared by repeated steaming and drying process in the immune-suppressed mice induced by pre (RD-A) or post-treatment (RD-B) with cyclophosphamide. The immune-stimulating effects of ethanol RD extract in in vivo at 150 (RD-1) and 300 mg/kg body weight (RD-2) for RD-A and RD-B groups were measured and compared to the NC group supplied with distilled water only or positive control group. After 14 days of oral supplement, serum IgA, IgG, and cytokine levels, splenocytes proliferation rate, NK cell activity, and gene expression of cytokines were measured as immune related biomarkers. Serum IgA, IgG, IL-1β, and IL-12 levels increased in both RD-A and RD-B groups while serum TNF-α level decreased in RD-A group compared to the NC group. Splenocytes proliferation rate, NK cell activity, and cytokine (IL-1β, IL-6, IFN-γ) expression levels were also improved by RD supplement in the both groups. The RD showed more significant immunomodulatory effects at higher dose (RD-2) rather than the lower dose (RD-1). Thus, RD has an immune efficacy in a dose dependent manner and can be used as an immune stimulating source to improve immunity.

• Nutritional Sciences
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• v.7 no.1
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• pp.3-7
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• 2004

This study was performed to investigate the effect of a raw diet (RD) on blood glucose and immune function in non-diabetic (normal) and streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley rats were assigned to four groups (normal control, normal RD, diabetic control and diabetic RD). The control groups and the RD groups were fed an AIN-diet and RD for four weeks, respectively. Weight gain was statistically lower in the RD groups than in the controls. Fasting plasma glucose was significantly lower in the diabetic RD group than in the diabetic control group. The $CD4^+$ T-cell population was higher along with the $CD4^+/CD8^+$ ratio of the mesenteric lymph nodes in the normal RD group compared to the other groups. It can be concluded that RD may reduce the plasma fasting glucose concentration in diabetic rats and improve mesenteric lymph node immune function in normal rats.

• Industry Promotion Research
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• v.8 no.2
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• pp.11-19
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• 2023

The purpose of this study is to analyze the effect of economic uncertainty on business innovation. To this end, Ahir et al. (2018) World Uncertainty Index (WUI) is selected as a proxy for economic uncertainty, while total R&D investment (RD), capitalized R&D investment (RD_A), expensed R&D investment (RD_E), and the proportion of capitalized R&D investment to total R&D investment (RD_R) are selected as variables representing business innovation. The research findings showed that economic uncertainty (WUI) had a statistically significant positive (+) relationship with total research and development investment (RD), asset-based research and development investment (RD_A), and the proportion of asset-based research and development investment (RD_R). This relationship remained the same even after controlling for managerial opportunistic accounting behavior (DACC; discretionary accruals). These findings suggest that companies focus on research and development investment as an opportunity for management innovation even in the face of economic uncertainty. The results of this study are significant in demonstrating the validity and effectiveness of government support for industrial promotion under economic uncertainty.

• Nutritional Sciences
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• v.6 no.3
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• pp.127-134
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• 2003

This study investigates the effects of a raw diet (RD) on blood glucose and lipid metabolism in non-diabetic (normal) and streptozotocin (STZ)-induced diabetic rats. Male Sprague-Dawley vats were assigned to four groups (normal control, normal RD, diabetic control, and diabetic RD), for the four-week experimental period. The control groups were fed the AIN diet and the RD groups were fed a diet consisting only of raw materials. Weight gain was statistically lower in the RD group than the control. fasting plasma glucose was significantly lower in the diabetic RD group compared to the diabetic control group. The levels of triglycerides (TG), and of total cholesterol (TC) and LDL-cholesterol in the plasma, were lower in the RD groups than the control groups, but not significantly. There was a statistically significant decrease in the levels of TG and TC in the livers of the diabetic RD group, compared to the diabetic control group. The fecal levels of total lipids, TG, and TC were significantly higher in the RD groups, compared to the non-RD groups. It can be postulated that this raw diet may possess substantial hypoglycemic/hypolipidemic properties in diabetic rats.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.3
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• pp.229-235
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• 2013

Among several animal models of retinitis pigmentosa (RP), the more recently developed rd10 mouse with later onset and slower rate of retinal degeneration than rd1 mouse is a more suitable model for testing therapeutic modalities. We therefore investigated the time course of retinal degeneration in rd10 mice before adopting this model in our interventional studies. Electroretinogram (ERG) recordings were carried out in postnatal weeks (PW) 3~5 rd10 (n=23) and wild-type (wt) mice (n=26). We compared the amplitude and implicit time of the b-wave of ERG records from wt and rd10 mice. Our results showed that b-wave amplitudes in rd10 mice were significantly lower and the implicit time of b-waves in rd10 mice were also significantly slower than that in wt mice ($20{\sim}160{\mu}V$ vs. $350{\sim}480{\mu}V$; 55~75 ms vs. 100~150 ms: p<0.001) through PW3 to PW5. The most drastic changes in ERG amplitudes and latencies were observed during PW3 to PW4. In multichannel recording of rd10 retina in PW2 to PW4.5, we found no significant difference in mean spike frequency, but the frequency of power spectral peak of local field potential at PW3 and PW3.5 is significantly different among other age groups (p<0.05). Histologic examination of rd10 retinae showed significant decrease in thickness of the outer nuclear layer at PW3. TUNEL positive cells were most frequently observed at PW3. From these data, we confirm that in the rd10 mouse, the most precipitous retinal degeneration occurs between PW3~PW4 and that photoreceptor degeneration is complete by PW5.

• Journal of Korean Academy of Nursing
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• v.35 no.6
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• pp.1072-1080
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• 2005

Purpose: This paper was conducted to test the reliability and validity of rd-SLS, developed by Podsakoff, et al. (1993) which measured 'substitutes for leadership'. Method: The subjects were 345 nurses in 5 general hospitals. Cronbach's and the Guttman split-half coefficient were used to test the reliability of rd-SLS. Factor analysis, and the correlations of the rv-SLS and SLS with rd-SLS were used for convergent and discriminant validity. Result: Cronbach's data was 0.76 and the Guttman split-half coefficient was 0.52. Twelve factors evolved by factor analysis, which explained $70.4\%$ of the total variance. This result was similar to previous study results. However, 'Indifference toward organizational rewards'-related items were classified two factors. It was not clear t hat the rd-SLS consisted of 13 concepts(factors). The correlations of the rv-SLS and SLS with the rd-SLS were 0.93 and 0.87 respectively. Conclusion: The rd-SLS showed a moderate degree of validity and reliability. Thus, it is recommended to use the rd-SLS in general nursing organizations for screening for leadership substitutes. In addition, it is necessary to clarify the concept of organizational rewards. In a further study, the factor structure of the rd-SLS may be considered.

• Journal of Astronomy and Space Sciences
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• v.12 no.2
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• pp.179-195
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• 1995

RT Per has been known as a close binary of which the orbital period has unpredictably varied so far. Although there are no agreements with the working mechanism for the changes of the period, two interpretations have been suggested and waiting for to be tested: 1) light-time effects due to the unseen 3rd and 4rd bodies (Panchatsaram 1981), 2) Abrupt period-changes, due to internal variations of the system (e.g. mass transfer or mass loss) superimposing to the light-time effect by a 3rd body (Frieboes-Conde & Herczeg 1973). In the point of view that the former interprepation models could predict the behavior of the changes of the orbital period theoretically, we checked whether the recent observed times of minimum lights follow the perdictions by the first model or not. We confirmed that the observed times of minimum lights have followed the variations calculated by the light-times effects due to the 3rd and 4rd bodies suggested by Panchatsatam. In this paper a total of 626 times of minimum lights were reanalyzed in terms of the light-time effects by the 3rd and 4rd bodies. We concluded that the eclipsing pair in SVCam system moves in an elliptic orbit about center of mass of the triple system with a period of about $42.^y2$, while the mass center of the triplet is in light-time orbit about the center of mass of the quadruple system with a period of $120^y$. The mean masses deduced for the 3rd and 4rd bodies were $0.89m_\odot$ and $0.82m_\odot$, respectively.