• Korean Journal of Ecology and Environment
• /
• v.38 no.spc
• /
• pp.27-30
• /
• 2005

Diel vertical migration (DVM) and horizontal distribution of Chaoborus flavicans larvae were studied in Lake Fukami-ike (maximum depth 7.75 m, Central Japan). The larvae showed a clear migration in the 4 ${\sim}$ 7 m layer during the day and throughout the water column at night. It should be noted that, while old instar distributed throughout the column during the night. Young instar was found only in the 1 ${\sim}$ 4 m layer. An examination of horizontal distribution revealed that larval stage was clearly related with the depth. It suggests that Chaoborus appear to exist in the deeper area during the larval stage.

• International Journal of High-Rise Buildings
• /
• v.10 no.3
• /
• pp.193-201
• /
• 2021

Cheongna City Tower is a 448-meter-high rise observatory tower with 8.7:1 aspect ratio located at central lake park in Incheon Cheongna international city. The tower is a crystal shaped image and it turns invisible when the façade is activated. The tower was planned to be hexagonal 30-story building with two basements which are composed of mega frame structure using mega column and mega brace. In order to minimize the wind effect, the blow-through area was installed so that the wind can pass through. This observatory tower is an unprecedented project since the whole building is covered by façade for invisibility effect.

• Bulletin of the Korean Mathematical Society
• /
• v.59 no.3
• /
• pp.617-642
• /
• 2022

For positive integers n and d with d < n, an n × n array A based on 𝒳 = {0, 1, …, nd} is called a sparse anti-magic square of order n with density d, denoted by SAMS(n, d), if each non-zero element of X occurs exactly once in A, and its row-sums, column-sums and two main diagonal-sums constitute a set of 2n + 2 consecutive integers. An SAMS(n, d) is called regular if there are exactly d non-zero elements in each row, each column and each main diagonal. In this paper, we investigate the existence of regular sparse anti-magic squares of order n ≡ 1, 5 (mod 6), and prove that there exists a regular SAMS(n, d) for any n ≥ 5, n ≡ 1, 5 (mod 6) and d with 2 ≤ d ≤ n - 1.

• Journal of the Korean Society of Tobacco Science
• /
• v.26 no.2 s.52
• /
• pp.159-167
• /
• 2004

This work has been conducted to select appropriate filter materials for removing carbonyl compounds in mainstream tobacco smoke. To investigate of the usability of this filter materials, two types of bead ion exchangers were synthesized and their adsorption characteristics for carbonyl compounds were investigated. Sulfonic acid group-containing cation exchanger and ammonium group-containing anion exchanger were synthesized by the suspension polymerization of glycidylmethacrylate(GMA) and divinylbenzene(DVB) followed by the subsequent functionalization, respectively. The removal efficiency of carbonyl compounds by these two ion exchangers increased in the presence of moisture. However, the amount of carbonyl compounds adsorbed on the anion exchanger was larger than that on the cation exchanger under two levels of water contents tested. This phenomenon seems to arise from the electron delocalization in carbonyl group of the anion exchangers. There was not any significant relationship between the amount of carbonyl compounds adsorbed on ion exchangers and the length of adsorption column. From the large ion exchange capacity and rapid ion exchange reaction rate of the anion exchanger, it is suggested that the anion exchanger may be a good filter material for removing carbonyl compounds in the mainstream tobacco smoke.

• Korean Journal of Pharmacognosy
• /
• v.38 no.4
• /
• pp.349-353
• /
• 2007

Skin wrinkle formations are associated with collagen synthesis and matrix metalloproteinase-I(MMP-1) activity. This study was carried out to find out skin wrinkle reducing components in Torilis Fructus. Torilis Fructus were extracted with 70% ethanol and the ethanol extracts were systematically fractionated with n-hexane, ethylacetate, n-butanol and distilled water. Among them, antiwrinkle component from n-hexane fraction was purified by several column chromatographies and HPLC, which identified as torilin by $^1H-NMR,\;^{13}C-NMR$ and ESI-MS. To determine cell viability, collagen biosynthesis and MMP-1 activity, human dermal fibroblast was treated with 1-5 ppm concentrations of Torilis Fructus extract fraction and torilin. Cell viability was showed 84-102% at all group treated with 1-5 ppm. Collagen synthesis was increased in all group, especially torilin-treated group was highest amount. Active forms of MMP-1 were decreased in all group. From these results, we consider that Torilis Fructus have several antiwrinkle components and torilin may be one of the effective components.

• Steel and Composite Structures
• /
• v.29 no.1
• /
• pp.77-90
• /
• 2018

This paper presents a combined numerical, experimental, and theoretical study on the behavior of the concrete-filled double circular steel tubular (CFDT) stub columns under axial compressive loading. Four groups of stub column specimens were tested in this study to find out the effects of the concrete strength, steel ratio and diameter ratio on the mechanical behavior of CFDT stub columns. Nonlinear finite element (FE) models were also established to study the stresses of different components in the CFDT stub columns. The change of axial and transverse stresses in the internal and external steel tubes, as well as the change of axial stress in the concrete sandwich and concrete core, respectively, was thoroughly investigated for different CFDT stub columns with the same steel ratio. The influence of inner-to-outer diameter ratio and steel ratio on the ultimate bearing capacity of CFDT stub columns was identified, and a reasonable section configuration with proper inner-to-outer diameter ratio and steel ratio was proposed. Furthermore, a practical formula for predicting the ultimate bearing capacity was proposed based on the ultimate equilibrium principle. The predicted results showed satisfactory agreement with both experimental and numerical results, indicating that the proposed formula is applicable for design purposes.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.7 no.6
• /
• pp.340-346
• /
• 2002

The purpose of the present study was to examine the efficacy and mechanism of the PAB (para-amino benzamidine) affinity column chromatography, Viresolve NFP virus filtration, pasteurization (60$\^{C}$ heat treatment for 10 h), and lyophilization steps employed in the manufacture of urokinase from human urine as regards the removal and/or inactivation of the hepatitis A virus (HAV). Samples from the relevant stages of the production process were spiked with HAV and subjected to scale-down processes mimicking the manufacture of urokinase Samples were collected at each step, immediately titrated using a 50% tissue culture infectious dose (TCID$\_$50/), and the virus reduction factors evaluated. PAB chromatography was found to be an effective step for removing HAV with a log reduction factor of 3.24. HAV infectivity was rarely detected in the urokinase fraction, while most of the HAV infectivity was recovered in the unbound and wash fractions. HAV was completely removed during the Viresolve NFP filtration with a log reduction factor of $\geq$ 4.60. Pasteurization was also found to be an effective step in inactivating HAV where the titers were reduced from an initial titer of 7.18 log$\_$10/ TCID$\_$50/ to undetectable levels within 10 h of treatment. The log reduction factor achieved during pasteurization was $\geq$ 4.76. Lyophilization revealed the lowest efficacy for inactivating HAV with a log reduction factor of 1.48. The cumulative log reduction factor was $\geq$ 14.08. Accordingly, these results indicate that the production process for urokinase exhibited a sufficient HAV reducing capacity to achieve a high margin of virus safety.

• Archives of Pharmacal Research
• /
• v.27 no.4
• /
• pp.460-464
• /
• 2004

The quality of Alismatis Rhizoma was evaluated by reversed-phase high performance liquid chromatographic method. Alisol B 23-acetate was used as a standard marker for evaluation. This component was fully separated from the other components in the plant extracts on a ODS column. Identifcation of alisol B 23-acetate was carried out by comparing the LC/MS spectrum of separated peak from the extract with that of standard. Alisol B 23-acetate contents in Alismatis Rhizoma obtained from several herbal markets were varied from $0. 15\%$ to $0.56\%$.

• Natural Product Sciences
• /
• v.10 no.3
• /
• pp.93-95
• /
• 2004

Eleven triterpenoids, colubrinic acid (1), alphitolic acid (2), 3-O-cis-p-coumaroyl alphitolic acid (3), 3-O-trans-p-coumaroyl alphitolic acid (4), 3-O-cis-p-coumaroyl maslinic acid (5), 3-O-trans-p-coumaroyl maslinic acid (6), betulinic acid (7), oleanolic acid (8), betulonic acid (9), oleanonic acid (10), and zizyberenalic acid (11), were isolated from the fruits of Zizyphus jujuba Mill. A simple and rapid HPLC method, using a $C_{18}$ column, has been developed for the quantitative analysis of these compounds 1 (0.74%),2 (0.09%), 3 (0.19%), 4 (0.19%), 5 (0.08%),6 (0.08%), 7 (0.41%), 8 (0.05%), 9 (0.50%),10 (0.59%), and 11 (0.19%).

• Proceedings of the Korean Biophysical Society Conference
• /
• 1999.06a
• /
• pp.35-35
• /
• 1999

Amylases catalyze the hydrolysis of starch material and play central roles in carbohydrate metabolism. The structure and a size exclusion column chromatography proved that the enzyme is a dimer in solution. The N -terminal segment of the enzyme folds into a distinct domain and comprises the enzyme active site together with the central (${\alpha}$/ ${\beta}$)$\sub$8/ barrel of the adjacent subunit.(omitted)