• Korean Journal of Pharmacognosy
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• v.32 no.1 s.124
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• pp.31-38
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• 2001

A lectin was purified from Allomyrina dichotoma (ADL) by physiological saline extraction, ammonium sulfate fractionation, anion exchange column chromatography on DEAE Sephadex A-50 and gel filtration column chromatography on Sephadex G-200. Several biochemical properties of ADL were characterized as follows: ADL from gel filtration column chromatography showed single band on SDS-PAGE. ADL agglutinated the erythrocytes of rabbit and human A, B, O, AB. Agglutinability was relatively stable at basic pH, and was stable at temperature below $40^{\circ}C$. Agglutinability was not affected by metal ions and EDTA. This lectin was proved to be a glycoprotein which contains 0.47% of sugars. The molecular weight of ADL was estimated to be 97,000 dalton by SDS-PAGE. By amino acid analysis, ADL exhibited high amounts of aspartic acid. The lectin's immunomodulating effect was measured as cytokine production. The productions of 5 cytokines $(IL-1{\alpha},\;IL-2,\;IL-6,\;IFN{\gamma}\;and\;TNF{\alpha})$ from peripheral blood mononuclear cells were measured by ELISA. The lectin induced the highest secretion of IL-2 at 8 hr, $TNF{\alpha}$ at 4 hr, and $IFN{\gamma}$ at 24hr, respectively. These results suggest that ADL can elicit the production of detectable cytokines from PBMC.

• Journal of the Korean Chemical Society
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• v.35 no.3
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• pp.196-203
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• 1991

The $pK_a$ values of benzoic acid and meta, para-halogen substituted benzoic acids in MeOH-$H_2O$ mixtures (0∼80% of MeOH) have been determined at 25$^{\circ}$C using a conductometric method on the basis of the Fuoss-Kraus equation, and further verified using modified conductometric method of Gelb. The dependence of $pK_a$ on halogen substituents has been discussed in terms of substituent-constant (${\sigma}$), which is devided into electron-withdrawing inductive contribution (${\sigma}_1$) and electron-donating ${\pi}$-resonance one (${\sigma}_R$). The linear-dependence of ${\sigma}_1$'s on $D^{-1}$ with positive slope and that of ${\sigma}_R$'s on $D^{-1}$ with negative slope have been interpreted on the basis of field effect and through-space interaction of ${\pi}$-lone pair of halogen substituent and ionization center via ${\pi}$-system of benzene ring.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.3
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• pp.189-197
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• 2007

The solubility of U(VI) hydrolysis products was determined by using a laser-induced breakdown detection (LIBD) technique. The experiments were carried out at uranium concentrations in range from $2{\times}10^{-4}\;M\;to\;4{\times}10^{-6}\;M$, pH values between 3.8 and 7.0, the constant ionic strength of 0.1 M $NaClO_4$ and the temperature of $25.0{\pm}0.1^{\circ}C$. The solubility product of U(VI) hydrolysis products was calculated from LIBD results by using the hydrolysis constants selected in NEA-TDB. The solubility product extrapolated to zero ionic strength, ${\log}K^{\circ}_{sp}=-22.85{\pm}0.23$ was calculated by using a specific ion interaction theory (SIT). The spectral features of ionic species in uranium solutions were investigated by using a conventional UV-visible absorption spectrophotometer and a fluorophotometer, respectively, $(UO_2)_2(OH)_2^{2+}\;and\;(UO_2)_3(OH)_5^+$ were dominant species at uranium concentration of $2{\times}10^{-4}\;M$.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.1
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• pp.63-72
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• 2020

Dissolved hexavalent uranium can exist in the form of several different chemical species. Furthermore, species distributions depend on the pH value of the aqueous solution. Representatively, UO₂²⁺, UO₂OH⁺, (UO₂)₂(OH)₂²⁺, and (UO₂)₃(OH)₅⁺ species coexist in solutions at acidic and circumneutral pH values. When amorphous silica particles are suspended in an aqueous solution, the dissolved chemical species are easily adsorbed onto silica surfaces. In this study, it was examined whether the species distribution of the adsorbed U(VI) on a silica surface followed that of the dissolved U(VI) in an aqueous solution. Time-resolved luminescence spectra of three different dissolved species (UO₂²⁺, UO₂OH⁺, and (UO₂)₃(OH)₅⁺) and two different adsorbed species (≡SiO₂UO₂, ≡SiO₂(UO₂)OH^-, or ≡SiO₂(UO₂)₃(OH)^5-) were measured in the pH range 3.5-7.5. The spectral shapes of these chemical species were compared by changing the pH value; consequently, it was confirmed that the species distribution of the adsorbed U(VI) species was different from that of the dissolved U(VI) species.

• Journal of dental hygiene science
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• v.12 no.1
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• pp.39-44
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• 2012

For the purpose of examining the dental biofilm reduction effect and control difficulty level through a dental biofilm control program in this study, the total of 131 medical records (82.9%) were used for the final analysis upon excluding the records that were not suitable for this study among the records of 158 persons for the medical records of clinical hygiene case reports that were submitted from 2006 to 2011 by students at the Department of Dental Hygiene at N University located in Chungnam region. The result of examining the dental biofilm reduction effect according to the visit number when conducting a dental biofilm control program showed that the dental biofilm index reduced meaningfully as the visit number increased. However, in the case of those that visited for 7 sessions, the level of reduction was not statistically meaningful. For the purpose of comparing the dental biofilm index mean per area of teeth during the final session visit of dental biofilm control program, the area of teeth was classified into labial/buccal surface, lingual/palatal surface and proximal surface, and the dental biofilm index of lingual/palatal surface was the highest with 26.5%. The result of measuring the dental biofilm of maxilla/mandible revealed meaningful differences between the dental biofilm index of maxilla and mandible. The result of analyzing the dental biofilm index of labial/buccal surface, lingual/palatal surface and proximal surface revealed meaingful differences among the dental biofilm index of labial/ buccal surface, lingual/palatal surface and proximal surface.

• Journal of dental hygiene science
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• v.12 no.6
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• pp.660-665
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• 2012

The purpose of this study was to use basic data of dental hygiene curriculum by comparing the rolling method and modified stillman method. Plaque measurement method, Q-ray examination of the clinical utilization value shall review. True experimental design is randomized controlled trial to the intervention group and the control group. Measurements are plaque control record (PCR; O'Leary index) measurements and Quantitative Light induced fluorescnece Digital (QLFD) shooting as a pre-test was conducted. Intervention group is modified stillman method, control group is rolling method. Intervention after 5 weeks, PCR measurement and QLFD shooting was carried out as a post-test. Rolling method and modified stillman method plaque reduction did not differ. Intervention before and after the results of the comparison showed reduced plaque score after brushing law education. Also, Plaque reduction differences were more pronounced modified stillman method than rolling method. PCR and QLFD values of the correlation was not confirmed but SPS Score and the lower value of the ${\Delta}R$ value of the correlation. Plaque of maturity tooth that are not observed visually.

• Journal of Astronomy and Space Sciences
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• v.41 no.3
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• pp.171-194
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• 2024

This study reports comprehensive observations for the G5-level geomagnetic storm that occurred from May 10 to 12, 2024, the most intense event since the 2003 Halloween storm. The storm was triggered by a series of coronal mass ejections (CMEs) originating from the merging of two active regions 13664/13668, which formed a large and complex photospheric magnetic configuration and produced X-class flares in early May 2024. Among the events, the most significant CME, driven by an X2.2 flare on May 9, caught up with and merged with a preceding slower CME associated with an X-class flare on May 8. These combined CMEs reached 1 AU simultaneously, resulting in an extreme geomagnetic storm. Geostationary satellite observations revealed changes in Earth's magnetosphere due to solar wind impacts, increased fluxes of high-energy particles, and periodic magnetic field fluctuations accompanied by particle injections. Extreme geomagnetic storms resulting from the interaction of the solar wind with the Earth's magnetosphere caused significant energy influx into Earth's upper atmosphere over the polar regions, leading to thermospheric heating and changes in the global atmospheric composition and ionosphere. As part of this global disturbance, significant disruptions were also observed in the East Asian sector, including the Korean Peninsula. Ground-based observations show strong negative storm effects in the ionosphere, which are associated with thermospheric heating and resulting in decreases in the oxygen-to-nitrogen ratio (O/N₂) in high-latitude regions. Global responses of storm-time prompt penetration electric fields were also observed from magnetometers over the East-Asian longitudinal sector. We also briefly report storm-time responses of aurora and cosmic rays using all-sky cameras and neutron monitors operated by the Korea Astronomy and Space Science Institute (KASI). The extensive observations of the G5-level storm offer crucial insights into Sun-Earth interactions during extreme space weather events and may help establish better preparation for future space weather challenges.