• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.2
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• pp.156-159
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• 2001

The experiment was carried out to investigate the productivity of freshwater rotifer, Brachionus calyciflorus and marine rotifer, B. rotundiformis at various temperatures, initial inoculation and pH in a 5 L semi-continuous high density culture. Rotifers were fed by commercial condensed freshwater Chlorella. When pH was not controlled, average daily productions of freshwater and marine rotifers increased with temperature. The highest production, $44\times10^6$ rotifers, was achieved of B. calyciflorus at $32^{\circ}C$ and the possible production lasting period of B. calyciflorus was shorter than that of B. rotundiformis. Under the adjustment of pH at 7, the possible production lasting periods of B. calyciflorus and B. rotundiformis inoculated with 5,000 inds./mL were longer than those of rotifers inoculated with 10,000 inds./mL, and the daily production rate of the former was higher than that of the latter. The results from this study indicated that optimum density of the initial inoculation for the cultivation of B. calyciflorus and B. rotundiformis was 5,000 inds,/mL under the controlled conditions of pH 7 and at $32^{\circ}C$ in a semi-continuous high density culture, in terms of production rate and food cost aspects.

• Journal of Environmental Health Sciences
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• v.24 no.2
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• pp.126-133
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• 1998

Effects of B(a)P on preimplantation mouse embryos in vitro were studied. Preimplantation mouse embryos were exposed to a concentration of 0.3, 1, 3 and 10 $\mu$M B(a)P for 72 hrs. The toxicological effects of B(a)P were evaluated by morphological observation of embryos up to the blastocyst stage, and by measuring DNA, RNA and protein synthesis by radioactive precursor incorporation. At 1 $\mu$M B(a)P did not affect preimplantation development but interfered with hatching and ICM formation. Suppressing effect of ICM formation was dose dependent. At the eight cell stage, the developmental rate was decreased at above 3 $\mu$M of B(a)P. At the blastocyst stage, attachment and trophoblast outgrowth were diminished at the 10 $\mu$M of B(a)P and ICM formation was decreased at 1 $\mu$M of B(a)P. Inner cell number of blastocyst was decreased dose dependently. So, number of ICM was one of the most sensitive and toxicological end point. The RNA incorporation rate of 0.1 $\mu ^3$H-uridine was dosedependent and the protein incroporation of 0.5 $\mu Ci ^{35}$S-methionine showed a significant decrease after 48 hrs. But the DNA incorporation rate of methyl-$^3$H thymidine was not affected. Our results suggested that B(a)P did not affect the DNA replication but transcription was inhibited by dose dependent manner. There delay of development during the blastocyst stage was mainly due to the inhibition of RNA synthesis followed by protein synthesis.

• The Korean Journal of Food And Nutrition
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• v.24 no.4
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• pp.797-802
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• 2011

I assessed the B($a$)P content from the Ginseng extract, Red ginseng extract, and Ssangwha extract which have high viscosities. It wasn't easy to extract oil from these samples, consequently measuring of B($a$)P was difficult. In order to know the exact detecting contents, I injected standard material of B($a$)P to the above extractions and pre-treated for measurement but it was also difficult to measure of contents exactly. To improve of detecting method, I removed mucinous materials using a 85% phosphoric acid solution or 10% citric acid solution and then processed continuously with $60^{\circ}C$ hot water. The analysis revealed that extracting the samples contained B($a$)P determined the rate of each 70%, 55%, 67% could increase. As a result the detecting method of B($a$)P contents could be improved.

• Food Science and Preservation
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• v.16 no.1
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• pp.75-81
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• 2009

Benzo(a)pyrene[B(a)P] levels were determined in processed oils and by-products of corn oil, and removal protocol was formulated. The cause of high level B(a)P contents in corn oil was established. Corn germ had a B(a)P level more than 80% that of whole corn. B(a)P content in final deodorized corn oil was $2.15{\mu}g/kg$, after the usual refining process. B(a)P contents less than $2.0{\mu}g/kg$ could not be attained by routine refining process. However, deodorized corn oil, with B(a)P level of $0.09{\mu}g/kg$, could be prepared by treatment of oil with approximately 2% (w/w) mixed granules(acidic clay:active carbon= 90:10[w/w]). The optimal amount of active carbon was 10% (w/w) that of acidic clay;higher levels of active carbon was not required. The optimal particle size of active carbon was $50{\sim}100$ mesh, removal of B(a)P from bleached corn oil was efficient at this mesh size.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.10B
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• pp.1701-1706
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• 2000

In this work a 38 GHz hybrid 2-stage power amplifier module using GaAs pHEMTs and waveguide to microstrip transitions has been successfully developed. A 10 mil thickness duroid substrate was use for fabrication of the power amplifier and the waveguide to microstrip transitions. The fabricated waveguide to microstrip transition showed about 1 dB insertion loss(back to back) at 32-40 GHz. The measured results of power amplifier module showed 29 dBm output power(P1.5dB), 7,2 dB associated gain and 11.2% power-added efficiency(PAE) at 36.8-38.5 GHz.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.845-851
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• 2002

The synthesis of the intramolecular donor - stabilized silyl and germyl complexes of the type ($Cab^c.p) MMe_2X$ (2a:M=Si, X=Cl;2b;M= Ge, X=Cl;2e;M=Si,X=H) was achieved by the reaction of $LiCab^c,p$ (1) with $Me_2SiClX$ and $Me_2GeCl_2$ respectively. The intramolecular M←P interacion in 2a-2c is provided by $^1H$, $13^C.$, $31^P$ and $29^Si$ NMR spectroscopy. The salt elimination reactions of dichlorotetramethyldisilane and -digermane with 1 afforded the $bis(\sigma-carboranylphosphino)disilane$ and disgermane [$(Cab^C.P)MMe_2]_2(4a;M$ = Si;4b: M=Ge). The oxidative addition reaction of 4a-4b with $pd_2(dba)_3CHCl_3afforded$ the bis(silyl)-and bis(germyl)-palladium complexes. The chloro-bridged dipalladium complexes were obtained by the reaction of 2a-2b with $pd_2(dba)_3CHCl_3$ The crystal structures of 5a and 7b were determined by X-ray structural studies.

• Korean journal of food and cookery science
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• v.9 no.4
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• pp.323-328
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• 1993

Benzo(a)pyrene [B(a)P], one of the polycyclic aromatic hydrocarbons (PAHs) is known as a potent carcinogen. As lipid consumption increases recently, the toxic effect of overheated lipid foods and fats ＆ oils were reported increasingly. In this study, the contents of B(a)p, other PAHs and rancidities of soybean oil were determined, and then the proper heating temperature, time and frequency were recommended, The work was carried out using soybean oil heated at $180\pm$5^{\circ}C$$, $200\pm$5^{\circ}C$$, and $300\pm$5^{\circ}C$$,for 50 hours. Acid Value(AV) and Conjugated Diene Value of samples were determined. The contents of B(a)P and other PAHs contents of all samples were masured by HPLC/UV method. The results obtained were as follows; Each content of PAHs in the fresh soybean oil was: Pyr 1.093, B(a)A 0.986, Ch 1.147, DMBA 1.082, B(e)P 0.664, Per 1.135, B(a)P 0.146, DBA 1.053, 3-MC 0.05 rg/kg. When the soybean oil was heated at $180\pm$5^{\circ}C$$, for 10, 20, 30, and 50 hours, B(a)P conterlts in heated soybean oils were 0.391, 0.692, 0.451, and 0.372 $\mu\textrm{g}$/kg respectively. Acid value of them were 0.26, 0.26, 0.29, and 0.33, and conjugated diene value was 0.67, 0.76, 0.99, and 1.04, respectively. When the soybean oil was heated at $200\pm$5^{\circ}C$$,and $300\pm$5^{\circ}C$$,for 10, 20, 30, and 50 hours, B(a)P coiltents in soybean oil heated at $200\pm$5^{\circ}C$$,were 0.844, 0.512, 0.479 and 0.247 Ig/kg respectively, Acid value 0.22, 0.21, 0.23 and 0.51 and CDNV 0.39, 0.49, 3.27, and 3.89. B(a)P contents in soybean oil heated at $300\pm$5^{\circ}C$$,were 0.466, 0.706, 0.607 and 0.247$\mu\textrm{g}$/kg respectively, Acid value 0.47, 1.57, 3.90, and 6.42 and CDNV 0.65, 2.15, 3.00, and 3.88.

• Bulletin of the Korean Mathematical Society
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• v.58 no.5
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• pp.1079-1095
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• 2021

In this paper, we give new congruences with the generalized Catalan numbers and harmonic numbers modulo p². One of our results is as follows: for prime number p > 3, $${\sum\limits_{k=(p+1)/2}^{p-1}}\;k^2B_{p,k}B_{p,k-(p-1)/2}H_k{\equiv}(-1)^{(p-1)/2}\(-{\frac{521}{36}}p-{\frac{1}{p}}-{\frac{41}{12}}+pH^2_{3(p-1)/2}-10pq^2_p(2)+4\({\frac{10}{3}}p+1\)q_p(2)\)\;(mod\;p^2),$$ where q_p(2) is Fermat quotient.

• Journal of Veterinary Clinics
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• v.28 no.2
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• pp.190-195
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• 2011

Nuclear factor ${\kappa}B$ (NF-${\kappa}B$) is a nuclear transcription factor that modulates the expression of inflammatory cytokines such as tumor necrosis factor (TNF)-${\alpha}$. trans-10, cis-12 (t10c12)-conjugated linoleic acid (CLA) participates in the inhibition of TNF-${\alpha}$ production upon lipopolysaccharide (LPS)-stimulation. However, in our previous study, t10c12-CLA enhanced the production of TNF-${\alpha}$ by LPS-unstimulated porcine peripheral blood mononuclear cells (PBMCs) and RAW 264.7 macrophages in vitro. To resolve this apparent contradiction, we hypothesized that the effect of t10c12-CLA on TNF-${\alpha}$ production depends on NF-${\kappa}B$ activation induced by LPS stimulation. To test this hypothesis, we assessed the in vitro effect of t10c12-CLA on TNF-${\alpha}$ production and NF-${\kappa}B$ p65 activity in LPS-stimulated and LPS-unstimulated porcine PBMCs. t10c12-CLA treatment resulted in increased TNF-${\alpha}$ production by LPS-unstimulated PBMCs but decreased TNF-${\alpha}$ production by LPS-stimulated PBMCs. t10c12-CLA increased the degradation of inhibitory ${\kappa}B$ ($I{\kappa}B$)-${\alpha}$ protein and activated NF-${\kappa}B$ p65 in LPS-unstimulated PBMCs, but had the opposite effect in LPS-stimulated PBMCs. Notably, t10c12-CLA enhanced NF-${\kappa}B$ p65 binding activity in LPS-unstimulated PBMCs exposed to caffeic acid phenethyl ester (CAPE), a NF-${\kappa}B$ inhibitor. Conversely, it inhibited NF-${\kappa}B$ p65 binding activity in LPS-stimulated PBMCs exposed to CAPE. These results suggest that t10c12-CLA may have different actions under different physiological conditions, and that its effect may be associated with a change in NF-${\kappa}B$ p65 activity.

• Journal of Applied Biological Chemistry
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• v.51 no.6
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• pp.272-276
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• 2008

Purification and some properties of Xylogone sphaerospora ${\beta}$-mannanase were reprevious previous paper. Locust bean gum galactomannan was hydrolyzed by the purified ${\beta}$-mannanase, and then the hydrolysates was separated by activated carbon column chromatography. The main hydrolysates were composed of D.P. (Degree of Polymerization) 4 and 6 galactosyl mannooligosaccharides. For elucidate the structure of D.P 4 and 6 galactosyl mannooligosaccharides, sequential enzymatic action was performed. D.P 4 and 6 were identified as ${Gal^2}{Man_3}\;(6^2-mono-O-{\alpha}-D-galactopyranosyl-4-O-{\beta}-D-mannotriose)$ and ${Gal^2}{Man_5}\;(6^2-mono-O-{\alpha}-D-galacto- pyranosyl-4-O-{\beta}-D-mannopentaose)$. To investigate the effects of locust bean gum galactosyl mannooligosaccharides on in vitro growth of Bifidobacterium longum, B. bifidum, B. infantis, B. adolescentis, B. animalis, B. auglutum and B. breve. Bifidobacterium spp. were cultivated individually on the modified-MRS medium containing carbon source such as D.P. 4 and D.P. 6 galactosyl mannooligosaccharides, respectively. B. longum and B. bifidum grew up to-fold and 6.6-fold more effectively by the treatment of D.P. 6 galactosyl mannooligosaccharides, compared to those of standard MRS medium. Especially, D.P. 6 was more effective than D.P. 4 galactosyl mannooligosaccharide on the growth of Bifidobacterium spp.