• 미생물학회지
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• 제9권3호
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• pp.130-138
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• 1971

배양조건에 따른 aflattoxin 생성능을 알기위하여 증대두배지에 Aspergillus flavus를 PH5.0 PH7.0 PH9.0 수분30%,45%,63%, 온도 2$0^{\circ}C$ 3$0^{\circ}C$ 4$0^{\circ}C$등의 조건으로 각각 배양한 27종의 시료와 Bacillus와 혼합배양한 3종의 시료를 AOAC 공정법에 의하여 aflatoxin의 생성량을 실험한 결과 다음과 같은 겨로가를 얻었다. 1. 각 PH에 의한 aflatoxin의 생성량은 PH5.0의 경우가 높았으며 PH7.0의 경우도 비교적 높은 편이었으나 PH9.0에서는 aflatoxin생성량이 현저히 감소되었다. 2. 수분합량에 따른 aflatoxin의 생성량은 수분이 적은 30%의 경우, 비교적 많은 양의 aflatoxin을 얻을 수 있었으며, 그 다음이 45%, 63% 으로서 수분함량이 많아질수록 aflatoxin의 생성이 감소되었다. 3.온도조건이 의한 결과는 Aspergillus flavus를 2$0^{\circ}C$로 배양하였을 때 가장 높은 aflatoxin의 생성량을 볼 수 있었으며, 3$0^{\circ}C$의 경우도 비교적 높은 양의 aflatoxin 생성을 볼 수 있으나 4$0^{\circ}C$의 경우는 aflatoxin의 생성은 낮았다. 4.여러가지 배양조건에 따른 Aspergillus flavus의 aflatoxin생성량은 수분 30% PH5.0 온도2$0^{\circ}C$일때 crude aflatoxin은 5.093ppm로 가장 높았으며 수분함량 63% PH 9.0 온도 4$0^{\circ}C$일때 crude aflatoxin의 량은 2.197ppm으로 aflatoxin 생성이 가장 낮았다. 5. Aspergillus flavus를 여러 조건하에서 배양한 결과 가장 많이 생성되는 배양조건인 온도 20 $^{\circ}C$ 수분 30%의 조건하에서 Bacillus subtilis와 혼합배양한 결과 Aspergillus flavus 단독배양의 경우보다 Bacillus subtilis균과 혼합배양하였을때 aflatoxin은 약 27%나 감소되었다.

• 대한본초학회지
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• 제33권3호
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• pp.37-43
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• 2018

Objectives : Butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) were well known as anti-oxidant, but they were limited to use because of toxicity. So, many studies are being done to develope natural anti-oxidant. Total phenolic and flavonoid contents along with total antioxidant capacity of the ethanolic extract of Plantaginis Herba (PH) were evaluated to explore the reliable and potential sources of novel natural antioxidants. Methods : Total polyphenol contents and total flavonoid contents in PH ethanol extract were determined by colorimetric method. And DPPH(1.1-diphenyl-2-picrylhydrazyl), ABTS(2'-azino-bis (3-ethylbenzothiazoline-6-Surfonicacid)) free radical scavenging capacity and reducing power inhibition activities of PH ethanol extract were measured at 100, 500, 1000, $5000{\mu}g/m{\ell}$ concentrations by spectrometric assay. Results : The total polyphenol contents and total flavonoid contents of the extract were 161.99 mg/g, 144.05 mg/g, respectively. Also, DPPH, ABTS free radical scavenging capacity and reducing power of PH ethanol extract in treated concentrations (100, 500, 1000, $5000{\mu}g/m{\ell}$) increased dose dependently. In particular, DPPH free radical scavenging capacity of PH ethanol extract from $500{\mu}g/m{\ell}$ was significantly increased compared to positive control (BHA). ABTS free radical scavenging capacity of PH ethanol extract from $1000{\mu}g/m{\ell}$ was significantly higher than BHA. Also, reducing power showed that PH ethanol extract from $500{\mu}g/m{\ell}$ was significantly increased compared to BHA. Conclusions : These results suggest that PH ethanol extract has effects to scavenge free radicals, thus PH has potential and applicable benefits for development of materials and products to have anti-oxidation functions.

• 한국어류학회지
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• 제35권4호
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• pp.217-223
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• 2023

잔가시고기 Pungitius kaibarae의 신규 집단인 고령(GR) 집단과 야생 집단의 특성을 규명하기 위해 미토콘드리아 cytb 유전자 영역의 886 bp 서열을 이용 총 4개 집단 (경상북도 고령(회천, GR), 포항(곡강천, PH), 경산(오목천, GYSA), 강원도 고성(배봉천, GS))을 분석하였다. 고령(GR) 집단에서 가장 낮은 haplotype 다양성을 나타냈고(H_d=0.000), 고성(GS) 집단에서 0.755로 가장 높은 haplotype 다양성을 확인하였다. Nucleotide 다양성은 고성(GS) 집단에서 0.00291로 가장 높은 다양성을 나타냈으며, 고령(GR) 집단에서 가장 0.00000로 가장 낮은 다양성을 보였다. 유전적 분화도에서 고령(GR) 집단은 포항(PH) 집단과 유전적으로 가장 가까운 것으로 나타났다. Haplotype 네트워크는 고령 (GR) 집단이 포항(PH) 집단과 군집되어 가장 유사한 것으로 나타났다. 고령(GR) 집단은 계통발생학적 tree에서 높은 지지도(98%)의 값으로 포항(PH) 집단과 군집됨을 확인하였다. 따라서 고령(GR) 집단은 포항(PH) 집단과 유사한 집단에서 유래됨을 추정하였다.

• 상하수도학회지
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• 제21권3호
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• pp.349-357
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• 2007

Reports of endocrine disrupting compounds (EDCs), pharmaceutically active compounds (PhACs), and personal care products (PCPs) have raised substantial concern in important potable drinking water quality issues. Our study investigates the removal of EDCs, PhACs, and PCPs of 10 compounds having different physico-chemical properties (e.g., molecular weight, and octanol-water partition coefficient ($K_{OW}$)) by nanofiltration (NF) membranes. The rejection of micropollutants by NF membranes ranged from 93.9% to 99.9% depending on solute characteristics. A batch adsorption experiments indicated that adsorption is an important mechanism for transport/removal of relatively hydrophobic compounds, and is related to the octanol-water partition coefficient values. The transport phenomenon associated with adsorption may also depend on solution water chemistry such as pH and ionic strength influencing the pKa value of compounds. In addition, it was visually seen that the retention was somewhat higher for the larger compounds based on their molecular weight. These results suggest that the NF membrane retains many organic compounds due to both hydrophobic adsorption and size exclusion mechanisms.

• 보건행정학회지
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• 제20권1호
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• pp.87-102
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• 2010

The objective of this study were to examine the impact of medicaid coverage expansion policy aimed at improving access to primary care. The case-control study was conducted to compare preventable hospitalization(PH) rate in new medicaid recipients versus national health insurance(NHI) enrollees form 1996 to 2001. Rates of preventable hospitalization associated with ambulatory care sensitive conditions(ACSC) were calculated and standardized by age and sex. Multinomial logit regression model was used to control the confounding factors such as age, gender and charlson comorbidity index Annual PH rates in the new medicaid increased 1.64 times after medicaid expansion, with controling confounding factors. Meanwhile, annual PH rate in the NHI increased 1.68 times during the same period, with adjusting confounding factors. Current findings suggest that the new medicaid PH rate was less likely to rise than NHI PH rate after implementing medicaid expansion. This study is expected to provide policy-relevant evidence of medicaid expansion to include population with low income.

• 한국식품영양과학회지
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• 제27권3호
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• pp.537-542
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• 1998

The present study was performed to elucidate desmutagenic principles from Ecklonia stolonifera extracts against 2-amino-1-methyl-6-phenylimidazo[4,5-b] pyridine(PhIP) and 2-amino-3,8-dime-thylimidazo[4,5-f]duinoxaline(MeIQx) with Salmonella/mammalian-microsome mutagenicity test. Alginate, phenols, chlorophyll and carotenoids from Ecklonia stolonifera were extracted and their desmutagenicities were assayed. Alginate hydroysates showed desmutagenic activities against PhIP and MeIQx at high level dose. Phenol fractions and bromophenol showed desmutagenic activity of about MeIQx at high level dose. Phenol fractions and bromophenol showed desmutagenic activity of about 90% per 0.5mg against PhIP and MeIQx. Chlorophyllin among chlorophyll derivatives exhibited remarkable desmutagenic activities of 92.9% and 82.7% at 20uM against PhIP and MeIQx, respectively. Carotenoids, such as lutein and $\alpha$-cryptoxanthin isolated from Ecklonia stolonifera exerted also high desmutagenic activity. Major desmutagenic substances from Ecklonia stolonifera are considered to be chlorophyllin, phenols, lutein, $\alpha$-cryptoxanthin and low molecular alginates.

• Bulletin of the Korean Chemical Society
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• 제26권2호
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• pp.233-237
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• 2005

Cyclopentadiene compounds, 2-[CR'R(OMe)]-1,3-Me$_2C_5H_3$ (R, R' = 2,2'-biphenyl, 2) and 2-[CR'R(OSiMe$_3$)]-1,3-Me$_2C_5H_3$ (R, R' = 2,2'-biphenyl, 3; R = ph, R' = ph, 4; R = 2-naphthyl, R' = H, 5) are readily synthesized from 2-bromo-3-methoxy-1,3-dimethylcyclopentene (1). Reaction of the cyclopentadienes with Ti(NMe$_2$)$_4$ in toluene results in clean formation of the cyclopentadienyl tris(dimethylamido)titanium complexes, which are transformed to the trichloride complexes, 2-[CR'R(OMe)]-1,3-Me$_2C_5H_2$}TiCl$_3$ (R, R' = 2,2'-biphenyl, 6) and {2-[CR'R(OSiMe$_3$)]-1,3-Me$_2C_5H_2$}TiCl$_3$ (R, R' = 2,2'-biphenyl, 7; R = ph, R' = ph, 8; R = 2-naphthyl, R' = H, 9). Attempts to form C1-bridged Cp/oxido complexes by elimination of MeCl or Me$_3$SiCl were not successful. X-ray structures of 6, 7 and an intermediate complex {2-[Ph$_2$C(OSiMe$_3$)]-1,3-Me$_2C_5H_2$}TiCl$_2$(NMe$_2$) (10) were determined.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.314-316
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• 1997

We have studied the epitaxial growth and electrical properties of $Si_{0.8}Ge_{0.2}$, films on Si substrates at $550^{\circ}C$ by LPCVD. In a low $PH_3$, partial pressure region such as below 1.25 mPa, the phosphorus doping concentration increased proportionally with increasing $PH_3$ partial pressure while the deposition rate and the Ge fraction x were constant. In a higher $PH_3$ partial pressure region, the phosphorus doping concentration and the deposition rate decreased, while the Ge fraction slightly increased. The dependence of P incorporation rate on the $PH_3$ partial pressure was similar to the phosphorus doping concentration. According to test results, it suggests that high surface coverage of phosphorus atoms suppress both the $SiH_4$ adsorption/reaction and the $GeH_4$ adsorption/reaction on the surfaces, and the effect is more stronger on $SiH_4$ than on $GeH_4$. In a higher $PH_3$ partial pressure region, the deposition is largely controlled by surface coverage effect of phosphorus atoms.

• Smart Structures and Systems
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• 제5권4호
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• pp.483-494
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• 2009

Damage detection has been proven to be a challenging task in structural health monitoring (SHM) due to the fact that damage cannot be measured. The difficulty associated with damage detection is related to electing a feature that is sensitive to damage occurrence and evolution. This difficulty increases as the damage size decreases limiting the ability to detect damage occurrence at the micron and submicron length scale. Damage detection at this length scale is of interest for sensitive structures such as aircrafts and nuclear facilities. In this paper a new photonic sensor based on photonic crystal (PhC) technology that can be synthesized at the nanoscale is introduced. PhCs are synthetic materials that are capable of controlling light propagation by creating a photonic bandgap where light is forbidden to propagate. The interesting feature of PhC is that its photonic signature is strongly tied to its microstructure periodicity. This study demonstrates that when a PhC sensor adhered to polymer substrate experiences micron or submicron damage, it will experience changes in its microstructural periodicity thereby creating a photonic signature that can be related to damage severity. This concept is validated here using a three-dimensional integrated numerical simulation.

• Animal cells and systems
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• 제5권3호
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• pp.263-266
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• 2001

Metallothionein (MT) is induced in the regenerating rat liver. We have investigated expression of MT gene by RT PCR as well as specific localization of MT by immunocytochemistry in regenerating rat liver after partial hepatectomy (PH). MT mRNA level started to increase from 1 h and reached the peak at 8 h after PH. The level decreased gradually by 24 h, and became similar to that of control group. In the immunocytochemical study, in all groups treated with primary antibody, immunogold particles indicating the presence of MT were evenly distributed throughout both cytoplasm and nucleus of the rat hepatocytes. Within the nucleus, the gold particles appeared to be intensely localized in the areas of euchromatin and nucleolus. Within the cytoplasm, gold particles did not seem to adhere to mitochondria or Iysosomes, but were freely distributed. However, rough endoplasmic reticulum was the obvious compartment on which the gold particles were localized. Time course of MT immunoreactivity revealed that distribution of gold particles in hepatocytes increased gradually by 24 h, and decreased at 48 h after PH. Briefly, PH resulted in the sharpest increase in the expression of MT mRNA at 8 h and in the immunoreactivity of MT at 24 h, respectively. It is suggested that the increase of MT mRNA expression, the intensity of immunoreactivity and the specific localization of MT may be associated with the compensatory cell proliferation followed by PH.