• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2335-2347
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• 2023

As medical facilities are usually built at urban areas, special concrete aggregates and evaluation methods are needed to optimize the design of concrete walls by balancing density, thickness, material composition, cost, and other factors. Carbon treatment rooms require a high radiation shielding requirement, as the neutron yield from carbon therapy is much higher than the neutron yield of protons. In this case study, the maximum carbon energy is 430 MeV/u and the maximum current is 0.27 nA from a hybrid particle therapy system. Hospital or facility construction should consider this requirement to design a special heavy concrete. In this work, magnetite is adopted as the major aggregate. Density is determined mainly by the major aggregate content of magnetite, and a heavy concrete test block was constructed for structural tests. The compressive strength is 35.7 MPa. The density ranges from 3.65 g/cm³ to 4.14 g/cm³, and the iron mass content ranges from 53.78% to 60.38% from the 12 cored sample measurements. It was found that there is a linear relationship between density and iron content, and mixing impurities should be the major reason leading to the nonuniform element and density distribution. The effect of this nonuniformity on radiation shielding properties for a carbon treatment room is investigated by three groups of Monte Carlo simulations. Higher density dominates to reduce shielding thickness. However, a higher content of high-Z elements will weaken the shielding strength, especially at a lower dose rate threshold and vice versa. The weakened side effect of a high iron content on the shielding property is obvious at 2.5 µSv=h. Therefore, we should not blindly pursue high Z content in engineering. If the thickness is constrained to 2 m, then the density can be reduced to 3.3 g/cm³, which will save cost by reducing the magnetite composition with 50.44% iron content. If a higher density of 3.9 g/cm³ with 57.65% iron content is selected for construction, then the thickness of the wall can be reduced to 174.2 cm, which will save space for equipment installation.

• Korean Journal of Remote Sensing
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• v.32 no.2
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• pp.119-131
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• 2016

Descriptions are provided of the automated aerosol-type classification and mass concentration calculation algorithm for real-time data processing and aerosol products in Korea Aerosol Lidar Observation Network (KALION, http://www.kalion.kr). The KALION algorithm provides aerosol-cloud classification and three aerosol types (clean continental, dust, and polluted continental/urban pollution aerosols). It also generates vertically resolved distributions of aerosol extinction coefficient and mass concentration. An extinction-to-backscatter ratio (lidar ratio) of 63.31 sr and aerosol mass extinction efficiency of $3.36m^2g^{-1}$ ($1.39m^2g^{-1}$ for dust), determined from co-located sky radiometer and $PM_{10}$ mass concentration measurements in Seoul from June 2006 to December 2015, are deployed in the algorithm. To assess the robustness of the algorithm, we investigate the pollution and dust events in Seoul on 28-30 March, 2015. The aerosol-type identification, especially for dust particles, is agreed with the official Asian dust report by Korean Meteorological Administration. The lidar-derived mass concentrations also well match with $PM_{10}$ mass concentrations. Mean bias difference between $PM_{10}$ and lidar-derived mass concentrations estimated from June 2006 to December 2015 in Seoul is about $3{\mu}g\;m^{-3}$. Lidar ratio and aerosol mass extinction efficiency for each aerosol types will be developed and implemented into the KALION algorithm. More products, such as ice and water-droplet cloud discrimination, cloud base height, and boundary layer height will be produced by the KALION algorithm.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.16 no.1
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• pp.18-23
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• 2016

Objective: Newborn screening leads to improved treatment and disease outcomes, but false-positive newborn screening results may impact include parental stress and anxiety, perception of child as unhealthy, parent-child relationship dysfunction, and increased infant hospitalizations. The purpose of this study was to investigate of the false positive rates and the causative factors of false positive results in Tandem Mass Spectrometry (TMS) in single center. Methods: Records were reviewed for all 18,872 subjects who were born in Cheill General Hospital, during January 1st, 2012 to December 31st, 2014. 17,292 neonates (91.62%) were tested for tandem mass screening almost in 2-5th day of life. Newborn babies whose first results were abnormal had been tested repeatedly by same methods in 7-14 day. If the results were abnormal again, further evaluation was performed. TMS analysis included data for the 43 disorders screened for using TMS broken down into three categories: fatty acid oxidation disorders, organic acidurias, and aminoacidopathies. The impact of several factors on increased false positive rates was analyzed using a multivariate analysis: time from birth to sample collection, birth weight, birth height, BMI, gender, gestational age, delivery type. Results: Males of the subjects were 8942 (51.7%), female 8350 (48.3%), the mean gestational age was $38.6{\pm}1.7$ weeks, the average birth weight $3,155.6{\pm}502.4g$, the average birth height $49.1{\pm}2.9cm$, and the average BMI $13.0{\pm}3.8(kg/m^2)$. Vaginal delivery cases were 9713 (56.2%), caesarean section 7,579 (43.8%). The average date of the inspection was $2.8{\pm}1.1$ days. 224 cases were identified as TMS positive. All the subjects were false positive (222/17,292, 1.30%) except 2 cases (1 male; benign phenylketonuria and 1 female; Short chain acyl-CoA dehydrogenase deficiency). The false positive rates were 0.61% in fatty acid oxidation disorders, 0.25% in organic acidurias, and 0.45% in aminoacidopathies. In our study, the date of inspection got late, the false positive rates got higher. Because almost the cases of late test date were in treatment in neonatal intensive care unit so their test date was affected by their medical conditions. False positive rate was higher in extreme immaturity${\leq}27$ weeks than newborns of gestational age >27 weeks [OR=6.957 (CI=1.273-38.008), p<0.025] and extremely low birth weight<1,000 g than newborns of birthweight ${\geq}1,000g$ [OR=5.616 (CI=1.134-27.820), p<0.035]. Conclusion: False positive rate of TMS was 1.30% in Cheil General Hospital. Lower gestational age and birth weight impacted on increased false positive rates. Better understanding of factors that influence the reporting of screening tests, and the ability to modify these important factors, may improve the screening process and reduce the need for retesting. of screening tests, and the ability to modify these important factors, may improve the screening process and reduce the need for retesting.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.37.4-38
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• 2018

The HULQ project proposes to use gravitational lensing to determine the masses of QSO host galaxies, an otherwise difficult goal. If these host galaxy masses, along with their SMBH masses from single-epoch measurements, are estimated for a substantial number of QSOs at various redshifts, the co-evolution of SMBHs and their host galaxies can be studied for a large portion of the history of the universe. To determine the feasibility of this study, we present how to estimate the number of sources lensed by QSO hosts, i.e. the number of lensing QSO host galaxies (hereafter QSO lenses). SMBH masses in the literature are transformed into the velocity dispersions of their host galaxies using the M_BH -sigma relation, and in turn the Einstein radii for each QSO -source redshift combination is calculated, assuming singular isothermal spherical mass distributions. Using QSOs and galaxies as potential sources, the probability of a QSO host galaxy being a QSO lens is calculated, as a function of limiting magnitude. The expected numbers of QSO lenses are estimated for ongoing and future wide-imaging surveys, and the Hyper Suprime-Cam Wide survey is illustrated as an example.

• Fisheries and Aquatic Sciences
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• v.15 no.2
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• pp.163-168
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• 2012

The non-utilized biomass of the aquacultured seaweed Undaria pinnatifida, particularly the rhizoid, is an alternative source of arachidonic acid (AA). Of the five aquacultured kelps that were tested, U. pinnatifida yielded the highest amount of AA, which was isolated from the rhizoids. Its identity (C20:4 n-6) was confirmed from gas chromatography-mass spectrometry spectral data. The optimal conditions for post-harvest storage or pretreatment of the rhizoids in Provasoli's enriched seawater for AA extraction were determined to be pH 7.8, 2% $CO_2$-enriched air, 20 ${\mu}mol\;m^{-2}\;s^{-1}$ light, and $10^{\circ}C$. Under these conditions, the AA content after 1 day of storage was enhanced by up to 127%. In the absence of light under ambient aeration, the AA content after 1 day of storage diminished to 90%. Rhizoids collected late in the season (April and May) contained the highest amounts of AA (approximately 2.5 mg/g tissue).

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.77.3-77.3
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• 2019

Aims. The evolution of scaling relations between SMBHs and their host galaxies becomes uncertain at high redshifts. The HULQ project proposes to use gravitational lensing to measure the masses of QSO host galaxies, an otherwise difficult goal. SMBH masses of QSOs are relatively easy to determine using either reverberation mapping or the single-epoch method. These measurements, if made for a substantial number of QSOs at various redshifts, will allow us to study the co-evolution of SMBHs and their host galaxies. To determine the feasibility of this study, we present how to estimate the number of sources lensed by QSO hosts, i.e. the number of deflector QSO host galaxies (hereafter QSO lenses). Method and results. Using SMBH masses measured from SDSS DR14 spectra, and the M_BH - Sigma relation, the Einstein radii are calculated as a function of source redshift, assuming singular isothermal sphere mass distributions. Using QSOs and galaxies as sources, the probability of a QSO host galaxy being a QSO lens is calculated, depending on the limiting magnitude. The expected numbers of QSO lenses are estimated for ongoing and future wide-imaging surveys, and additional factors that may affect these numbers are discussed.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4397-4402
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• 2011

The NF-${\kappa}B$ system of transcription factors plays a crucial role in inflammatory diseases, making it an important drug target. We combined quantitative structure activity relationships for predicting the activity of new compounds and quantitative dynamic models for the NF-${\kappa}B$ network with intracellular concentration models. GFA-MLR QSAR analysis was employed to determine the optimal QSAR equation. To validate the predictability of the $IKK{\beta}$ QSAR model for an external set of inhibitors, a set of ordinary differential equations and mass action kinetics were used for modeling the NF-${\kappa}B$ dynamic system. The reaction parameters were obtained from previously reported research. In the IKKb QSAR model, good cross-validated $q^2$ (0.782) and conventional $r^2$ (0.808) values demonstrated the correlation between the descriptors and each of their activities and reliably predicted the $IKK{\beta}$ activities. Using a developed simulation model of the NF-${\kappa}B$ signaling pathway, we demonstrated differences in $I{\kappa}B$ mRNA expression between normal and different inhibitory states. When the inhibition efficiency increased, inhibitor 1 (PS-1145) led to long-term oscillations. The combined computational modeling and NF-${\kappa}B$ dynamic simulations can be used to understand the inhibition mechanisms and thereby result in the design of mechanism-based inhibitors.

• Journal of Magnetics
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• v.16 no.3
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• pp.318-321
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• 2011

A new Fe-based amorphous compound powder was prepared from Fe-Si-B amorphous powder by crushing amorphous ribbons as the first magnetic component and Fe-Cr-Mo metallic glassy powder by water atomization as the second magnetic component. Subsequently by adding organic and inorganic binders to the compound powder and cold pressing, the new Fe-based amorphous compound powder cores were fabricated. This new Fe-based amorphous compound powder cores combine the superior DC-Bias properties and the excellent core loss. The core loss of 500 kW/$m^3$ at $B_m$ = 0.1T and f = 100 kHz was obtained When the mass ratio of FeSiB/FeCrMo equals 3:2, and meanwhile the DC-bias properties of the new Fe-based amorphous compound powder cores just decreased by 10% compared with that of the FeSiB powder cores. In addition, with the increasing of the content of the FeCrMo metallic glassy powder, the core loss tends to decrease.

• Journal of Nutrition and Health
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• v.40 no.7
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• pp.630-638
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• 2007

This study was performed to examine the combined effects of L-carnitine and isoflavone supplementation on weight reduction and body fat distribution in overweight women. Overweight/obese women (body mass index > $23kg/m^2$) who were not diagnosed any type of diseases were included in this study and sixty subjects ($41.1{\pm}1.5$ years, $25.9{\pm}0.3kg/m^2)$ were randomly assigned to a placebo (n=30) or a supplement group (n=30, L-carnitine 300 mg+isoflavone 40 mg/day). We measured anthropometric parameters, abdominal fat distribution by computerizd tomography and blood components before and after the 12 week intervention period. After the 12 weeks of supplementation, subjects in L-carnitine and isoflavone supplement group showed a significant reduction of body weight (p < 0.001), body fat % (p < 0.05), and waist to hip ratio (p < 0.01) whereas placebo group did not show any changes. In a CT-scanned results, total fat area at L4 level was significantly reduced by 8.1% (p < 0.01) with the reduction of visceral fat area (-11.1%, p < 0.001) and subcutaneous fat area (-7.0%, p < 0.05) in the supplement group. The supplementation of L-carnitine and isoflavone showed the significant improvement of HDL-C (p < 0.01) and apoB (p < 0.05) concentrations, however, change values in those markers were not significant compared with those of the placebo group. In addition, a significant increase of adiponectin level (p<0.001) was observed in the supplement group after the intervention. The result of present study demonstrated that supplementation of 300 mg L-carnitine and 40 mg isoflavone per day fur 12 weeks can give beneficial effects on weight reduction and visceral fat accumulation. These potential antiobesity supplement can produce more favorable effects when combined with lifestyle modification.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.332-338
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• 2009

A xylan-decomposing bacterium, HY-20, was isolated from the gut of a honeybee, Apis mellifera, and identified as Bacillus sp. The extracellular GH11 xylanase (XylP) gene (687-bp) of strain HY-20 encoded a protein of 228 amino acids with a deduced molecular mass of 25,522 Da and a calculated pI of 9.33. The primary structure of XylP was 97% identical to that of B. pumilus xylanase (GenBank accession no.: AY526092) that has not been characterized yet. The recombinant His-tagged enzyme (rXylP) overexpressed in Escherichia coli BL21 harboring pET-28a(+)/xylP was purified to electrophoretic homogeneity by cation exchange and gel permeation chromatographies. The purified enzyme exhibited the highest catalytic activity toward birchwood xylan at pH 6.5 and $50^{\circ}C$ and retained approximately 50% of its original activity when pre-incubated at $55^{\circ}C$ for 15 min. The recombinant enzyme was completely inactivated by $Hg^{2+}$ (1 mM) and N-bromosuccinimide (5 mM), while its activity was slightly stimulated by approximately 10% in the presence of $Mn^{2+}$ (1 mM), $Fe^{2+}$ (1 mM), and sodium azide (5 mM). rXylP was able to efficiently degrade various polymeric xylose-based substrates but PNP-sugar derivatives and glucose-based polymers were not susceptible to the enzyme.