• Korean Journal of Materials Research
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• v.6 no.7
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• pp.733-741
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• 1996

In this study MeV Si self ion implantations were done to reveal the intrinsic behavior of defect formation by excluding the possibility of chemical interactions between substrate atoms and dopant ones. Self implantations were conducted using Tandem Accelerator with energy ranges from 1 to 3 MeV. Defect formation by high energy ion implantation has a significant characteristics in that the lattice damage is concentrated near Rp and isolated from the surface. In order to investigate the energy dependence on defect formation, implantation energies were varied from 1 to 3 MeV under a constant dose of $1{\times}10^{15}/cm^2$. RBS channe!ed spectra showed that the depth at which as-implanted damaged layer formed increases as energy increases and that near surface region maintains better crystallinity as energy increases. Cross sectional TEM results agree well with RBS ones. In a TEM image as-implanted damaged layer appears as a dark band, where secondary defects are formed upon annealing. In the case of 2 MeV $Si^+$ self implantation a critical dose for the secondary defect formation was found to be between $3{\times}10^{14}/cm^24$ and $5{\times}10^{14}/cm^2$. Upon annealing the upper layer of the dark band was removed while the bottom part of the dark band did not move. The observed defect behavior by TEM was interpreted by Monte Carlo computer simulations using TRIM-code. SIMS analyses indicated that the secondary defect formed after annealing gettered oxygen impurities existed in silicon.

• Journal of the Korean Chemical Society
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• v.29 no.6
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• pp.565-574
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• 1985

The rates of reaction between 4-substituted-2,6-dinitrochlorobenzenes with para-substituted anilines in methanol-acetonitrile mixtures were measured by conductometry. It was observed that the rate constant increases in the order of X = 4-$NO_2 {\gg}4-CN {\gg}4- CF_3$, where X is a substituent in the substrate. The rate constant also increases in the order of Y = p-O$CH_3{\gg}p- CH_3{\gg}H {\gg}p-Cl{\gg}m- NO_2$, where Y is a substituent in the aniline ring. Kinetic studies in the methanol-acetonitrile solvent system with various nucleophiles showed that the N-C bond forming step is making a great contribution to the overall second order rate constant. The electrophilic catalysis by methanol probably consists of the hydrogen bonding between alcoholic hydrogen and leaving chloride in the transition state. The nucleophilic catalysis by methanol may be ascribed to the formation of hydrogen bonds between alcoholic oxygen and hydrogens of amines in the transition state. All these experimental facts are supporting the operation of $S_N$Ar machanism with the second step being the rate determining. This mechanism can be successfully fitted to the PES model.

• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1339-1343
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• 2005

The N-inversion energies and nucleophilic ring-opening reactions of N-substituted aziridine compounds are investigated using B3LYP/6-31+$G^*$ methods, where substituents (R) on the nitrogen atom has been H (1), Me (2), Ph (3), Bn (4), CHMePh (5), $CO_2Me$ (6), COPh (7) and $SO_2Ph$ (8). The N-inversion energy with X group are decreased as the following order: R = CHMePh (17.06 kcal/mol) $\gt$ Me (16.97) $\gt$ Bn (16.70) $\gt$ H (16.64) $\gt$ $SO_2Ph$ (12.18) $\gt$ Ph (8.91) $\gt$ COPh (5.75) $\gt$ $CO_2Me$ (5.48). For reactivity of the ring opening toward cyanide ion, the aziridine 6 (R=$CO_2Me$) is shown to be the most reactive one. During the ring opening of aziridine 6 by CN$^{\ominus}$, the torsional OCNC angle becomes near to $180^{\circ}$, where the geometry allows for the effective incorporation of electrons of the nitrogen atom to the C=O bond. It would be a possible driving force for nucleophilic ring opening reaction as well as decreasing the N-inversion energy barrier. Regarding to the regioselectivity, the orientation of nucleophile in ring opening reaction appears to be different in the case of 9 and 10. The results are discussed in terms of steric/electronic effect of the $C_2$-substituents.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.4
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• pp.352-362
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• 2008

In the mobile ad hoc network, network nodes are continuously capable of movement, but have battery limitations and these characteristics of MANET cause network link failure. Therefore, when performing ubiquitous services with the application of MANET, a technique is required to improve the packet transmission rates as to enable continuous packet transmission while flexibly adapting to topology changes caused by the mobility of nodes. In this paper, we are proposing PAOMDV(Possibility based AOMDV) and OLSR-ME(OLSR with Modified Energy Efficiency) which are mixed-type protocols to solve the problem for design a more efficient protocol. Especially by classifying mobile ad hoc networks as clusters, OLSR-ME protocol is implemented on communication within the clusters, while PAOMDV is used in protocols between clusters. In addition, a selection algorithm for forwarding nodes that responding packet relays in the case of increased hops was proposed for designing a more efficient protocol than existing protocols. We verified the performance of the proposed protocols through a comparative experiment with AODV, AOMDV, ZRP, and the existing protocols. We confirmed the results of the experiment revealed that the proposed protocol had the best packet transmission rate, the shortest delay between nodes, and showed better results in routing overhead.

• Journal of Nutrition and Health
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• v.55 no.2
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• pp.227-239
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• 2022

Purpose: This study investigated the effects of water-soluble mulberry leaf extract (ME) on hepatic lipid accumulation in high-fat diet-fed rats via the regulation of hepatic microRNA (miR)-221/222 and inflammation. Methods: Male Sprague-Dawley rats (4 weeks old) were randomly divided into 3 groups (n = 7 each) and fed with 10 kcal% low-fat diet (LF), 45 kcal% high-fat diet (HF), or HF + 0.8% ME for 14 weeks. Lipid profiles and cytokine levels of the liver and serum were measured using commercial enzymatic colorimetric and enzyme-linked immunosorbent assay, respectively. The messenger RNA (mRNA) and miR levels in liver tissue were assayed by real-time quantitative reverse-transcription polymerase chain reaction. Results: Supplementation of ME reduces body weight and improves the liver and serum lipid profiles as compared to the HF group. The mRNA levels of hepatic peroxisome proliferator-activated receptor-gamma, sterol regulatory element binding protein-1c, fatty acid synthase, and fatty acid translocase, which are genes involved in lipid metabolism, were significantly downregulated in the ME group compared to the HF group. In contrast, the mRNA level of hepatic carnitine palmitoyl transferase-1 (involved in fatty acid oxidation) was upregulated by ME supplementation. Furthermore, administration of ME significantly downregulated the mRNA levels of inflammatory mediators such as hepatic tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), monocyte chemoattractant protein-1, and inducible nitric oxide synthase. The serum levels of TNF-α, IL-6, and nitric oxide were also significantly reduced in ME group compared to the HF group. Expression of hepatic miR-221 and miR-222, which increase in the inflammatory state of the liver, were also significantly inhibited in the ME group compared to the HF group. Conclusion: These results indicate that ME has the potential to improve hepatic lipid accumulation in high-fat diet-fed rats via modulation of inflammatory mediators and hepatic miR-221/222 expressions.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.74-74
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• 1997

Chicory is used popularly. We use leaves of the plant as ordinary mea1, and roots as a substitute of tea materials. It also has been asserted that it has clinical effects on weakness, hepatic disease, diabetes, etc. However, experimental evidences are so insufficient that we started these studies. For antiinflammatory activity, MeOH Ex. was orally administered to rats, and decreased amounts of paw edema induced by carrageenan injection were measured. For bile secretion increament, rats were administered total MeOH, EtOAc fraction, and BuOH fraction Ex. respectively. One hour later, bile ducts were cannulated, and we collected bile every 20 minutes for 4 hours. For hepatoprotective activity, CCl$_4$-intoxicated mouse were treated with MeOH Ex., then s-GPT, S-GOT, and liver weight were measured. For antidiabetic activity, rats were induced diabetes by streptozocin 45mg/kg(i.v) injection. One week later, 1000mg/kg of total MeOH Ex. of chicory root was orally administered. We divided rats into three groups. Group 1 rats were administered only once, group 2 ones once a day for one week, and group 3 ones for three weeks. The concentrations of serum glucose were measured before and after administration. For antihypertensive activity, SHR were administrated total MeOH Ex. of chicory once a day for 8 days, and were measured blood pressure on 1st, 3rd, 6th and 8th day. Total MeOH, EtOAc fraction, and BuOH fraction Ex. increased bile secretion in rats, and decreased liver toxicity induced by CCl$_4$ in mouse. Total MeOH, Ex. of chicory roots has antiinflammatory effect, and decreased blood glucose concentration in group 2 and 3 rats. It was revealed not lowering blood pressure significantly in SHR.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.546-553
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• 2017

Objective: An experiment was conducted to determine digestible energy (DE) and metabolizable energy (ME) of different byproduct feed ingredients fed to growing pigs, and to generate prediction equations for the DE and ME in feed ingredients. Methods: Twelve barrows with an initial mean body weight of 31.8 kg were individually housed in metabolism crates that were equipped with a feeder and a nipple drinker. A $12{\times}10$ incomplete Latin square design was employed with 12 dietary treatments, 10 periods, and 12 animals. A basal diet was prepared to mainly contain the corn and soybean meal (SBM). Eleven additional diets were formulated to contain 30% of each test ingredient. All diets contained the same proportion of corn:SBM ratio at 4.14:1. The difference procedure was used to calculate the DE and ME in experimental ingredients. The in vitro dry matter disappearance for each test ingredient was determined. Results: The DE and ME values in the SBM sources were greater (p<0.05) than those in other ingredients except high-protein distillers dried grains. However, DE and ME values in tapioca distillers dried grains (TDDG) were the lowest (p<0.05). The most suitable regression equations for the DE and ME concentrations (kcal/kg on the dry matter [DM] basis) in the test ingredients were: $DE=5,528-(156{\times}ash)-(32.4{\times}neutral\;detergent\;fiber\;[NDF])$ with root mean square error = 232, $R^2=0.958$, and p<0.001; $ME=5,243-(153 ash)-(30.7{\times}NDF)$ with root mean square error = 277, $R^2=0.936$, and p<0.001. All independent variables are in % on the DM basis. Conclusion: The energy concentrations were greater in the SBM sources and were the least in the TDDG. The ash and NDF concentrations can be used to estimate the energy concentrations in the byproducts from oil-extraction and distillation processes.

• Korean journal of food and cookery science
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• v.8 no.3
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• pp.309-314
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• 1992

The purpose of this study was to investigate me effects of garlic or lemon juice on quality characteristics of fish muscle. The samples treated with garlic or lemon juice by me amount of 5% or 10% (w/w) of fish muscIe were stored at $4{\pm}1^{\circ}C$ and $-18{\pm}2^{\circ}C$ for 10 and 40 days, respectively. The results are summarized as follows; 1. In me taste of samples, me samples treated with 5% garlic juice showed me most favorite tendency all me storage time at $4{\pm}1^{\circ}C$ and $-18{\pm}2^{\circ}C$. 2. There were significant in fishy odor after 5 days of storage at $4{\pm}1^{\circ}C$ and 40 days of storage at $-18{\pm}2^{\circ}C$ . The fishy odor of samples treated with garlic juice were weaker man those of samples untreated or treated with lemon juice. 3. The appearance was evaluated the worst in 10% lemon juice treated sample among all me samples. 4. The hardness of the samples treated with lemon juice were lower man those of samples untreated or treated with garlic juice during all the storage time at $4{\pm}1^{\circ}C$ and $-18{\pm}2^{\circ}C$. 5. The score of overall quality was the highest in sample treated with 5% garlic juice during all the storage time at $-18{\pm}2^{\circ}C$.

• Ocean and Polar Research
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• v.40 no.4
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• pp.249-257
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• 2018

Matrix metalloproteinases (MMPs) are associated with the invasion and metastasis of malignant tumors composed of cancer cells in an increased state of expression. This study evaluates the inhibitory effect of Carex pumila on MMP-2 and MMP-9 activity in phorbol-12-myristate-13-acetate (PMA)-stimulated HT-1080 human fibrosarcoma cells using gelatin zymography, MMPs enzyme-linked immunosorbent assay (ELISA), reverse transcription-polymerase chain reaction (RT-PCR) and Western blot assay. C. pumila was extracted twice with dichloromethane ($CH_2Cl_2$) and methanol (MeOH). Treatment with $CH_2Cl_2$ extract and MeOH extract in PMA-stimulated HT-1080 cells effectively reduced the production of MMP-2 and 9. Also, the combined crude extracts ($CH_2Cl_2$ and MeOH) significantly inhibited the enzymatic activities and the expression of MMP-2 and MMP-9 in mRNA and protein levels. The combined crude extracts were partitioned between $CH_2Cl_2$ and water. The organic layer was further fractionated with n-hexane, 85% aqueous methanol (85% aq.MeOH) and the aqueous layer was separated into n-butanol and water, successively. Of the fractions, 85% aq.MeOH fraction showed the highest inhibitory activity of MMP-2 and MMP-9 in gelatin zymography and MMP ELISA kit. Furthermore, 85% aq.MeOH fraction most significantly suppressed cell migration. In RT-PCR and Western blot assay, n-butanol and 85% aq.MeOH fractions exerted the greatest inhibition on mRNA and protein expression of MMP-2 and MMP-9, respectively. As a result, C. pumila can be used as a good anti-invasive agent source.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.6C
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• pp.459-470
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• 2008

In this paper, we propose a fast ME (motion estimation) algorithm for MPEG-4 to H.264 Transcoder. Whereas 2 modes ($8{\times}8$, $16{\times}16$) are used for ME in MPEG-4 simple profile, ME using 7 modes is supported for further enhanced coding efficiency in H.264. The transcoding speed is affected dominantly by the computational complexity of encoder part in transcoder, where ME module of H.264 encoder has high complexity due to using 7 modes. In order to increase the speed of transcoding between MPEG-4 and H.264, we use 3 PMVs (predicted motion vectors) and the mode information of MBs (macroblocks) provided from the decoder part of transcoder. Since the proposed 3 PMVs are very close to an optimal motion vector, and we consider only some restricted modes according to the MB information transferred from decoder part, the proposed scheme can speed up the transcoding procedure without loss of image quality. We show experimental results which demonstrate the effectiveness of the proposed algorithm, where performance of our scheme is compared with that of the conventional fast algorithm for H.264.