• Title/Summary/Keyword: MC21

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Sorption of Eu on MX-80 Bentonite in Na-Ca-Cl Brine Solutions

  • Yang, Jieci;Racette, Joshua;Garcia, Fabiola Guido;Nagasaki, Shinya;Yang, Tammy
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.20 no.2
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    • pp.151-160
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    • 2022
  • The sorption of Eu on MX-80 bentonite in Na-Ca-Cl solutions is investigated at a molal proton concentration (pHm) range of 3 to 10 and an ionic strength (I) range of 0.1 to 6 m (mol·kgw-1). The sorption equilibrium of Eu on MX-80 is achieved within 14 to 21 d at I = 0.1 and 6 m. The sorption distribution coefficient (Kd) values of Eu for MX-80 increase as pHm increases from 3 to 6 for all I values, and they are independent of pHm between 8 and 10 at I ≥ 0.5 m. Meanwhile, at I = 0.1 m, the Kd value at pHm = 10 is slightly lower than those at pHm = 8 and 9. The Kd values are not affected by the I values between 0.5 m and 6 m, whereas the Kd value at I = 0.1 m is greater than those at I ≥ 0.5 m, except at pHm = 10. A two-site protolysis nonelectrostatic surface complexation and cation exchange sorption model is applied to the Eu sorption data for I ≤ 4 m, and the equilibrium constants of the sorption reactions are estimated.

A Kinetic Study of Phosphate Absorption by Rice Roots (벼에 의한 인산흡수의 기작에 관한 연구)

  • 장남기
    • Journal of Plant Biology
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    • v.21 no.1_4
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    • pp.33-38
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    • 1978
  • Phosphate absorption from a Na2H32PO4 solution by Oryza sativa L. was studied in order to elucidate kinetic mechanisms of ion transport. The rates of phosphate absorption from different concentraitons indicated the presence of dual mechanisms in root tips, one in the low (1$\times$10-6 to 8$\times$10-5M) and the other in the high (1$\times$10-4 to 8$\times$10-3M). A phosphate compensation point of phosphate transport was revealed with a 1$\times$10-6M solution of Na2H32PO4. The kinetic model that ion transport involves an exchange reaction of absorption and desorptin is prosposed as follows: where C represents an ionic-specific organic carrier in the membrane; M, Mo and Mi are the mineral ions, M-outside and M-inside; MC is a carrier-ion complex; and the K's represent rate constants. In this model, the Mi velocity, v, is given by: {{{{v= {dMi} over {dt}= {(K1K3Mo-K2K4Mi) Ct} over {(K2+K3)+K1Mo+K4Mi} }} where Ct is equal to C+MC, and t is time.

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Studies on the Collapse of four domestic Fagaceae Species (우리나라산(産) 참나무과(科) 4수종(樹種)의 Collapse에 관한 연구(硏究))

  • Park, Jong-Su;Kim, Su-Chang
    • Journal of the Korean Wood Science and Technology
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    • v.21 no.3
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    • pp.37-44
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    • 1993
  • The collapse of four domestic Fagaceae species was observed in relation with their moisture content(MC), basic density, P (Percent of moisture content saturation of the wood) and Q (Percent of cell cavity volume containing water) and the variation of collapse phenomenon in the cross section of stem was also investigated. The results were summarized as follows : The values of collapse in each species were great in order of Quercus dentata, Quercus variabilis, Quercus aliena and Quercus mongolica and the values were higher in heartwood than in sapwood in all of specimen. MC, basic density, P and Q were important factors which affected on the occurance of collapse and the collapse phenomenon was decreased from pith to bark.

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NIST PQC Round 4 코드 기반 암호에 대한 부채널 분석 기법 동향 분석

  • JeongHwan Lee;GyuSang Kim;HeeSeok Kim
    • Review of KIISC
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    • v.33 no.1
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    • pp.13-21
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    • 2023
  • NIST는 2022년 양자내성암호 표준화 진행 대상 알고리즘으로 KEM 1종(CRYSTALS-Kyber), 전자서명3종(CRYSTALS-Dilithium, FALCON, SPHINCS+)을 발표하였고, 추가로 KEM 4종(Classic McEliece, HQC, BIKE, SIKE)에 대한 Round 4 진행을 공표하였다. Round 3와 마찬가지로 Round 4에서도 부채널 분석 및 오류 주입에 대한 안전성은 알고리즘 선정에 있어 중요 평가 사항 중 하나이다. 따라서 해당 암호 알고리즘에 대한 새로운 부채널 분석기술에 대한 연구가 활발히 진행되고 있다. 본 논문은 Round 4의 암호 알고리즘 중 코드 기반 알고리즘 3종(Classic McEliece, HQC, BIKE)에 대한 부채널 분석 방법론의 동향을 파악하고 향후 연구 방향을 제시한다.

The Effects of PDGF-BB on the ALP Activity of MC3T3-E1 Cells (MC3T3-E1 세포의 ALP activity에 대한 PDGF-BB의 영향)

  • Lee, Kyung-Hee;Lee, Jae-Mok;Choi, Byung-Ju;Yu, Hyun-Mo;Suh, Jo-Young
    • Journal of Periodontal and Implant Science
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    • v.27 no.4
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    • pp.685-700
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    • 1997
  • The ultimate aim of periodontal treatment is periodontal regeneration, which necessiates the regeneration of bone tissues. This paper investigated the effect of growth factor on bone cells. Platelet-derived growth factor(PDGF) is the one of the polypeptide growth factor that has been reported as a biological mediator which regulates activities of the cell proliferation, migration and metabolism of undifferentiated mesenchymal cells. The purpose of this study is to evaluate the effects of PDGF on bone nodule formation and ALP activity of MC3T3-El cells. Cells were seeded at $1{\times}10^5cells/well$ in alpha-modified eagle medium containing 10% fetal bovine serum, lOml beta-glycerophosphate and $50{\mu}g/ml$ of ascorbic acid. PDGF 0, 0.1, 1, 10 ng/ml were added to the cells at a confluent state and cultured for 3, 7, 14, 21, 28 days. We examined bone nodule formation and alkaline phosphatase activity. The results were as follows : There were bone nodule formation at day 21 both in control and all the experimental groups, and at day 28, all the experimental groups showed much more bone nodules than control groups. Compared to control-l group, ALP activity was increased in PDGF O.1ng/ml group and was decreased in 1,10ng/ml PDGF treated groups.{P< 0.05, P< 0.01) Compared to control-2, ALP activity was decreased in all the experimental groups except PDGF 0.1ng/ml in 21 day group. In the time-response effect, ALP activity was increased by the day 14 in all the experimental groups and thereafter ALP activity was decreased.(P<0.05, P< 0.01) In the dose-response effect, ALP activity was decreased as the dose of PDGF was increased, and after 21 day ALP activity was lowest in 1 ng/ml group, ALP activity was highest in the day 7 in control group and 0.1 ng/ml, 14 day experimental group. In conclusion, PDGF is considered more effective in the proliferation than differentiation of osteoblast-like cells, and it may be useful to study the combined effect of PDGF and other growth factors on osteoblast-like cells.

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The Effects of Swim Training on Neurogenesis in the Hippocampal Dentate Gyrus and Functional Ability After Focal Ischemic Stroke in Rats (수영 훈련이 뇌허혈 유발 흰쥐의 해마 치아이랑에서 뇌신경생성과 기능적 능력에 미치는 영향)

  • Kim, Ho-Sung;Kim, Deuk-Ho;Lee, Jeong-Pil;Kim, Young-Joo;Shin, Young-Oh;Kim, Sang-Hoon;Kwon, Ki-Wook;Oh, Jae-Keun
    • Physical Therapy Korea
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    • v.12 no.3
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    • pp.11-21
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    • 2005
  • The present study was aimed at investigating the effect of swimming training on brain function after focal cerebral ischemia in rats. Therefore, this study was examined on neurogenesis in dentate gyrus of hippocampus using 5-bromo-2'-deoxyuridine (BrdU) to label proliferating cells and assessed the neurological response following focal cerebral ischemia in rats using neurological motor behavioral test. In an observer-blinded fashion, twenty male Sprague-Dawley (280~310 g, 7 weeks old) rats were divided into four groups: MCAO plus swimming group (ME, $n_1$=5), MCAO plus control group (MC, $n_2$=5), SHAM plus swimming group (SE, $n_3$=5), SHAM plus control group (SC, $n_4$=5). The results of this study were as follows: 1) The limb placing time before and after swimming in the ME group were significantly longer than the MC group (p<.05), the SE group were significantly longer than the SC group (p<.01). 2) The balance beam scores before and after swimming in the ME group was higher than the SE group, the MC group was higher than the SC group but was not significantly different (p>.001). 3) The foot fault index before and after swimming training in ME group was significantly lower (i.e., improved) than the MC group (p<.001) and the SE group (p<.001), the SE group was significantly lower (i.e., improved) than the SC group (p<.001). 4) The mean number of BrdU-positive cells in the dentate gyrus in the ME group was significantly higher than the MC group (p<.001) and the SE group (p<.01). The MC group and the SE group was significantly higher than the SC group (p<.001). 5) There was significantly correlation between limb placing time and number of BrdU-positive cells on swimming training, there was positive correlation (r=.807, p<.0001) and between foot fault index and BrdU-positive cells number, there was negative correlation (r=-.503, p<.05). However, between balance beam scores and BrdU-positive cells number, there was no correlation. In conclusion, the present study demonstrates that the role of swimming training improves behavioral motor function probably by enhancing cell proliferation in that hippocampus. This study provides a model for investigating the stroke rehabilitation that underlies neurogenesis and functional ability.

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Effects of Petasites japonicus and Momordica charantia L. Extracts on MC3T3-E1 Osteoblastic Cells (머위(Petasites japonicus)와 여주(Momordica charantia L.) 추출물의 MC3T3-E1 조골세포 증식 및 분화에 미치는 효과)

  • Ji, Suk-Hee;Ahn, Do-Hwan;Jun, Mi-Ra
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.2
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    • pp.203-209
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    • 2010
  • In this study, the effects of Petasites japonicus and Momordica charantia L. extracts on MC3T3-ET1 osteoblastic cells were investigated. Since the activity of osteoblastic cell is one of the important factors for bone formation, the cellular proliferation of osteoblast was evaluated by MTT and alkaline phosphatase (ALP) activity. Compared to control, the cell proliferation was elevated to 114% and 112% by the treatment of Petasites japonicus and Momordica charantia L. extracts, respectively at the concentration of $10\;{\mu}g/mL$. The cell differentiation was also measured by alkaline phosphatase (ALP) activity at 3, 7, 14, and 27 days treatments with one of the extracts, respectively. As results, the ALP activity was significantly increased at 3 days, compared to control (p<0.05). To evaluate the effect of Petasites japonicus and Momordica charantia L. extracts on bone nodule formation, MC3T3-E1 cells were cultured in $\alpha$-MEM for 3, 14, and 21 days and then stained by alizarin red. To determine the expression patterns of bone-related proteins during the MC3T3-E1 osteoblast-like cell differentiation, osteoblast cells were cultured in $\alpha$-MEM for 24 hr. RNA was extracted and RT-PCR analysis was performed to examine the expression of OPG, RANKL and osteocalcin. Petasites japonicus extract exhibited the significant increment of osteocalcin compared with the positive control, which suggests that Petasites japonicus may have beneficial effects on bone health through the proliferation of osteoblast cells.

Endemicity of Zoonotic Trematode Metacercariae in Fish from Deokcheon-gang (River) in Sancheong-gun, Gyeongsangnam-do, Republic of Korea

  • Sohn, Woon-Mok;Na, Byoung-Kuk;Cho, Shin-Hyeong;Lee, Hee Il;Ju, Jung-Won;Lee, Myoung-Ro;Park, Jeong-Gil;Ahn, Jihee
    • Parasites, Hosts and Diseases
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    • v.59 no.5
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    • pp.523-529
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    • 2021
  • The endemicity of zoonotic trematode metacercariae (ZTM) was investigated with total 871 freshwater fishes (19 species) from Deokcheon-gang (a branch stream of Gyeongho-gang) in Sancheong-gun, Gyeongsangnam-do, Korea for 3 years (2018-2020). All fishes were examined with the artificial digestion method. The metacercariae of Clonorchis sinensis (CsMc) were detected in 233 (36.3%) out of 642 fish in 11 positive fish species (PFS), and their infection intensity was 27 per fish infected (PFI). Especially, in index fish, Puntungia herzi, of CsMc infection, prevalence was 64.2% and infection intensity was 37 PFI. Metagonimus spp. metacercariae (MsMc) were found in 760 (87.5%) out of 869 fish in 18 PFS and their infection intensity was 228 PFI. In sweet smelt, Plecoglossus altivelis, the prevalence of MsMc was 97.6% and their infection intensity was 3,570 PFI. Centrocestus armatus metacercariae were detected in 209 (29.4%) out of 710 fish in 8 PFS and their infection intensity was 1,361 PFI. Echinostoma spp. metacercariae were found in 293 (42.6%) out of 688 fish in 15 PFS and their infection intensity was 5 PFI. Metacercariae of Clinostomum complanatum and Metorchis orientalis were also detected in 2.7% and 21.2% fish in 4 PFS and their infection intensities were 3.1 and 3.4 PFI respectively. By the present study, it was confirmed that some species of ZTM including CsMc and MsMc are more or less prevalent in fishes from Deokcheon-gang in Sancheong-gun, Gyeongsangnam-do, Korea.

Nystatin Drug as an Effective Corrosion Inhibitor for Mild Steel in Acidic Media- An Experimental and Theoretical Study

  • Mehmeti, Valbone
    • Corrosion Science and Technology
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    • v.21 no.1
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    • pp.21-31
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    • 2022
  • Potentiodynamic polarization, EIS measurements, quantum chemical calculations, and molecular dynamic simulations were used to investigate the corrosion behavior of mild steel in 0.5 M aqueous hydrochloric acid medium in the presence or absence of nystatin drug. Potentiodynamic tests suggested that this molecule could act as a mixed inhibitor due to its adsorption on the mild steel surface. The objective of this study was to exploit theoretical calculations to gain a better understanding mechanism of inhibition. Calculating the adsorption behavior of the investigated molecule on Fe (1 1 0) surface was accomplished using Monte Carlo simulation. Molecules were also investigated using Density Functional Theory (DFT), specifically PBE functional, in order to identify the link between molecular structure and corrosion inhibition behavior of the compound under investigation. Adsorption energies between nystatin and iron were estimated more accurately by utilizing Molecular Mechanics calculation with Periodic Boundary Conditions (PBC). Estimated theoretical parameters significantly assisted our understanding of the corrosion inhibition mechanism exhibited by this molecule. They were found to be in accord with experimental results.

Protective effect of ethyl acetate fraction from Actinidia arguta sprout against high glucose-induced in vitro neurotoxicity (포도당으로 유도된 in vitro 뇌신경세포 독성에 대한 다래 순 아세트산에틸 분획물의 보호 효과)

  • Yoo, Seul Ki;Park, Seon Kyeong;Kim, Jong Min;Kang, Jin Yong;Park, Su Bin;Han, Hye Ju;Kim, Chul-Wo;Lee, Uk;Heo, Ho Jin
    • Korean Journal of Food Science and Technology
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    • v.50 no.5
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    • pp.517-527
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    • 2018
  • The current study investigated in vitro anti-diabetic and neuroprotective effects of the ethyl acetate fraction in Actinidia arguta sprouts (EFAS), on $H_2O_2$ and high glucose-induced cytotoxicity in human neuroblastoma MC-IXC cells. EFAS had high total phenolic and total flavonoid contents. An assessment of 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity of EFAS, as well as its potential for inhibiting malondialdehyde production, indicated that EFAS may possess significant antioxidant properties. EFAS exerted inhibitory effects on ${\alpha}-glucosidase$ via glycemic regulation which forms advanced glycation end products. In addition, EFAS exhibited significant acetylcholinesterase inhibitory effects. Moreover, EFAS displayed protective effects against $H_2O_2$ and high glucose-induced cell death, and inhibited the generation of reactive oxygen species in MC-IXC cells. Finally, the main physiological compound of EFAS was identified via high performance liquid chromatography as a rutin.