• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3335-3339
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• 2013

Boron-doped ZnO (BZO) nanorods were grown on quartz substrates using hydrothermal synthesis, and the temperature-dependence of their photoluminescence (PL) was measured in order to investigate the origins of their PL properties. In the UV range, near-band-edge emission (NBE) was observed from 3.1 to 3.4 eV; this was attributed to various transitions including recombination of free excitons and their longitudinal optical (LO) phonon replicas, and donor-acceptor pair (DAP) recombination, depending on the local lattice configuration and the presence of defects. At a temperature of 12 K, the NBE produces seven peaks at 3.386, 3.368, 3.337, 3.296, 3.258, 3.184, and 3.106 eV. These peaks are, respectively, assigned to free excitons (FX), neutral-donor bound excitons ($D^{\circ}X$), and the first LO phonon replicas of $D^{\circ}X$, DAP, DAP-1LO, DAP-2LO, and DAP-3LO. The peak position of the FX and DAP were also fitted to Varshni's empirical formula for the variation in the band gap energy with temperature. The activation energy of FX was about ~70 meV, while that of DAP was about ~38 meV. We also discuss the low temperature PL near 2.251 eV, related to structural defects.

• Journal of Ginseng Research
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• v.44 no.2
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• pp.300-307
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• 2020

Background: Emerging evidence suggests that endothelial-to-mesenchymal transition (EndMT) in endothelial dysfunction due to persistent inflammation is a key component and emerging concept in the pathogenesis of vascular diseases. Ginsenoside Rg3 (Rg3), an active compound from red ginseng, has been known to be important for vascular homeostasis. However, the effect of Rg3 on inflammation-induced EndMT has never been reported. Here, we hypothesize that Rg3 might reverse the inflammation-induced EndMT and serve as a novel therapeutic strategy for vascular diseases. Methods: EndMT was examined under an inflammatory condition mediated by the NOD1 agonist, γ-d-glutamyl-meso-diaminopimelic acid (iE-DAP), treatment in human umbilical vein endothelial cells. The expression of EndMT markers was determined by Western blot analysis, real-time polymerase chain reaction, and immunocytochemistry. The underlying mechanisms of Rg3-mediated EndMT regulation were investigated by modulating the microRNA expression. Results: The NOD1 agonist, iE-DAP, led to a fibroblast-like morphology change with a decrease in the expression of endothelial markers and an increase in the expression of the mesenchymal marker, namely EndMT. On the other hand, Rg3 markedly attenuated the iE-DAP-induced EndMT and preserved the endothelial phenotype. Mechanically, miR-139 was downregulated in cells with iE-DAP-induced EndMT and partly reversed in response to Rg3 via the regulation of NF-κB signaling, suggesting that the Rg3-miR-139-5p-NF-κB axis is a key mediator in iE-DAP-induced EndMT. Conclusion: These results suggest, for the first time, that Rg3 can be used to inhibit inflammation-induced EndMT and may be a novel therapeutic option against EndMT-associated vascular diseases.

• Journal of IKEEE
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• v.22 no.2
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• pp.495-498
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• 2018

In this paper, we propose an DAP system for dose evaluation of medical and industrial X-ray generator. Based on the DAP measurement technique using the Ion-Chamber, the proposed system can clearly measure the exposure radiation dose generated by the diagnostic X-ray apparatus. The hardware part of the DAP measures the amount of charge in the air that is captured by an X-ray. The high-speed processing algorithm part for cumulative radiation dose measurement through microcurrent measures the amount of charge captured by X-ray at a low implementation cost (power) with no input loss. The wired/wireless transmission/reception protocol part synchronized with the operation of the X-ray generator improves communication speed. The PC-based control program part for interlocking and aging measures the amount of X-ray generated in real time and enables measurement graphs and numerical value monitoring through PC GUI. As a result of evaluating the performance of the proposed system in an accredited testing laboratory, the measured values using DAP increased linearly in each energy band (30, 60, 100, 150 kV). In addition, since the standard deviation of the measured value at the point of 4 division was ${\pm}1.25%$, it was confirmed that the DAP showed uniform measurements regardless of location. It was confirmed that the normal operation was not less than ${\pm}4.2%$ of the international standard.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.4
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• pp.357-363
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• 1997

The effect of replacement of cotton seed meal (CSM), with various levels and sources of non-protein nitrogenous (NPN), substances on in vitro ruminal fermentation were studied. Cotton seed meal, in control ration provided nitrogen equivalent to 12.5 percent crude protein while in experimental ration was replaced at 30, 50 & 70 percent levels with urea, diammonium phosphate (DAP) and biuret, respectively. The results of incubation upto 48 hours indicated an improvement in digestibility by replacement of CSM with urea and biuret upto 50 percent protein equivalent, but not with DAP. Bacterial count from cultures containing 50% nitrogen from biuret was significantly higher than DAP, urea and CSM. Various sources of nitrogen produced $NH_3-N$ in increasing order of CSM, biuret, DAP and urea. Increasing levels of NPN resulted in progressive increase in the levels of $NH_3-N$. The levels of various NPN sources had no effect on pH. However, the pH values determined for urea and CSM were higher than biuret and DAP.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.226-232
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• 2016

Dihydrodipicolinate reductase is an enzyme that converts dihydrodipicolinate to tetrahydrodipicolinate using an NAD(P)H cofactor in L-lysine biosynthesis. To increase the understanding of the molecular mechanisms of lysine biosynthesis, we determined the crystal structure of dihydrodipicolinate reductase from Corynebacterium glutamicum (CgDapB). CgDapB functions as a tetramer, and each protomer is composed of two domains, an Nterminal domain and a C-terminal domain. The N-terminal domain mainly contributes to nucleotide binding, whereas the C-terminal domain is involved in substrate binding. We elucidated the mode of cofactor binding to CgDapB by determining the crystal structure of the enzyme in complex with NADP⁺ and found that CgDapB utilizes both NADH and NADPH as cofactors. Moreover, we determined the substrate binding mode of the enzyme based on the coordination mode of two sulfate ions in our structure. Compared with Mycobacterium tuberculosis DapB in complex with its cofactor and inhibitor, we propose that the domain movement for active site constitution occurs when both cofactor and substrate bind to the enzyme.

• Journal of the Korea Concrete Institute
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• v.11 no.4
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• pp.43-54
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• 1999

Shear tests are performed on four full-scale 12.5 m proto-type models, "least depth double tee," which are resulted from the optimization process. Domestic superimposed live load regulation, domestic material properties which is available to product. Korean building code requirements, construction environments and economy are considered as the main factors to establish the process. All of the specimens tested fully comply with the shear strength requirements as specified by ACI 318-95. The research has shown following results. 1) The development length requirement of ACI 318-95 does not seem a good predictor for the estimation of bond failure in a beam with the strands below the supports. 2) The load required for the first initial coner cracking in the dap end and first web shear cracking does not seem to have any relation with the dimension and shear strength of the section in the test beams. 3) The strand slip has a direct relationship with the web shear cracking. However, the coner cracking in the dap end does not give any help for the slip in anchorage. 4) Use of whole area for bearing steel at the bottom of dap end is desired for safe bearing pressure design in the precast prestressed double tee beams. 5) The deflection of beam influences directly on the amount of strand slip at the anchorage after initiation of it, and relationship between them are very linear.

• Journal of the Korea Society for Simulation
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• v.20 no.4
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• pp.59-66
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• 2011

This work presents an algorithm for generating multi-RUN (m-RUN) deadlock avoidance policy based on simulated annealing algorithm. The basic idea of this method is to gradually improve the current m-RUN DAP after constructing an initial m-DAP by using simple m RUN DAPs. The search for a neighbor of the current m-RUN DAP is done by selecting and changing only one component of the current m-RUN, while accepting some unimproved solutions with some probability. It is examined for its performance by generating some sample system configurations.

• Korean Journal of Child Studies
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• v.29 no.3
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• pp.23-40
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• 2008

This study investigated the beliefs in Developmentally Appropriate Practice (DAP) of 447 mothers of 4- and 5- year-old children by mother's childhood experience, parenting efficacy, and parenting behavior. Results showed that mother's beliefs in DAP were related to children's age, early childhood educational institution, monthly household income, mother's educational background, mother's childhood experience, parenting efficacy, and parenting behavior. Mothers with higher beliefs in DAP were mothers of kindergarten rather than mothers of daycare children; they had 4 years or more college education, and more than $3000 monthly household income.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.252-257
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• 2004

본 연구에서는 인산염을 이용여 납으로 오염된 Clay 사격장과 인위적으로 오염시킨 자연토양의 중금속의 고정화 실험을 수행하였다. 인산염 고정화제로는 DAP (diammonium phosphate)를 사용하였다. DAP를 투입한 중금속 오염토양을 고정화 실험과 TCLP로 용출 하였을 때, 99% 정도 고정화되었다. 인산염 투여양이 증가할수록 고정화 효율은 증가하는 것으로 나타났으며, 최적 인투입량은 128 mmol as P/kg인 것으로 나타났다. DAP 투입양이 증가할수록 토양의 pH는 증가하는 것으로 나타났으며, 토양의 초기 pH 변화에 따라 고정화 효율은 크게 변하지 않은 것으로 나타났으나, pH가 높을수록 고정화 효율은 작은폭으로 증가하는 것으로 나타났다.

• Journal of the Korean Society of Radiology
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• v.13 no.3
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• pp.371-379
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• 2019

The purpose of this study was to investigate the effect of the change in the X-ray condition on the entrance surface dose (ESD) and dose area product (DAP) in the cine imaging of coronary angiography (CAG), and to analyze the usefulness of the condition change on the dose relation and image quality by measuring and analyzing the Signal to Noise Radio (SNR) and Contrast to Nois Ratio (CNR) of the angiographic images taken by the Image J program. Data were collected from 33 patients (24 males and 9 females) who underwent CAG at this hospital from November 2017 to March 2018. In terms of imaging condition and data acquisition, the ESD and DAP of group A with a high tube current of 397.2 mA and group B with a low tube current of 370.7 mA were retrospectively obtained for comparison and analysis. For the SNR and CNR measurement and analysis via Image J, the result values were derived by substituting the obtained data into the formula. The correlations among ESD and DAP according to the change in the imaging condition, SNR, and CNR were analyzed by using the SPSS statistical analysis software. The relationships of groups A and B, having a difference in the imaging condition, mA, with ESD ($A:483.5{\pm}60.1$; $B: 464.4{\pm}39.9$) and DAP ($A:84.3{\pm}10.7$; $B:81.5{\pm}7$) were not statistically significant (p>0.05). In the relationships with SNR and CNR based on Image J, the SNR ($5.451{\pm}0.529$) and CNR ($0.411{\pm}0.0432$) of the images obtained via the left coronary artery (LCA) imaging of group B showed differences of $0.475{\pm}0.096$ and $-0.048{\pm}0.0$, respectively, from the SNR ($4.976{\pm}0.433$) and CNR ($0.459{\pm}0.0431$) of the LCA of group A. However, the differences were not statistically significant (p<0.05). In the SNR and CNR obtained via the right coronary artery (RCA) imaging, the SNR ($4.731{\pm}0.773$) and CNR ($0.354{\pm}0.083$) of group A showed increased values of $1.491{\pm}0.405$ and $0.188{\pm}0.005$, respectively, from the SNR ($3.24{\pm}0.368$) and CNR ($0.166{\pm}0.033$) of group B. Among these, CNR was statistically significant (p<0.05). In the correlation analysis, statistically significant results were shown in SNR (LCA) and CNR (LCA); SNR (RCA) and CNR (RCA); ESD and DAP; ESD and sec; DAP and CNR (RCA); and DAP and sec (p<0.05). As a result of the analyses on the image quality evaluation and usefulness of the dose change, the SNR and CNR were increased in the RCA images of the CAG obtained by increasing the mA. Based on the result that CNR showed a statistically significant difference, it is believed that the contrast in the image quality can be further improved by increasing the mA in RCA imaging.