• 한국작물학회지
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• 제43권2호
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• pp.77-82
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• 1998

Aerenchyma development in rice (Oryza sativa L.) roots is quite important for adaptation to waterlogged or reduced soil conditions. Anatomical observations were carried out to clarify the development of schizogenous and lysigenous aerenchyma in elongating crown roots of rice. The crown roots of 3rd and 4th phytomer were taken from rice plants of the 8th leaf stage grown by hydroponic culture. The schizogenous intercellular spaces in the cortex of crown root tip were observed using a light microscope with semi ultra-thin sections and the lysigenous aerenchyma in mature tissue of crown root were observed using a cryo scanning electron microscope (cryo-SEM) with freezing fracture method. The schizogenous intercellular spaces in the root tip exist obviously in the middle portion of cortical cell layers close to the root-root cap junction, but not in root cap, stele and outer cell layers of cortex. The air spaces were formed at the junction of four neighbouring cells of inner cortex in the transverse sections, and between longitudinal cell layer connected along the root axis. Although many of those spaces were filled with liquid, some spaces seem to exist as air spaces. The lysigenous aerenchyma in the cortex, which hardly filled with liquid, emerged at 3-4 cm segment from the root tip and increased toward the basal region of root axis. The developing process of lysigenous aerenchyma was primarily separation of a radial row of cells caused by the shrinking and collapsing of cortical cells and then formation of septa along the radial cell rows by the fusion of cell wall with each other. These results suggest that the schizogenous and lysigenous aerenchyma playa role as a passage for the movement of oxygen into the root tip region where oxygen is required for respiration.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2011년도 한국우주과학회보 제20권1호
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• pp.20.1-20.1
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• 2011

We present the results of far-ultraviolet (FUV) observations of comet C/2001 Q4 (NEAT) obtained with Far-ultraviolet Imaging Spectrograph (FIMS) on board the Korean microsatellite STSAT-1, which operated at an altitude of 700 km in a sun-synchronous orbit. FIMS is a dual-channel imaging spectrograph (S channel 900-1150 ${\AA}$, L channel 1350-1750 ${\AA}$, ${\lambda}/{\Box}{\lambda}$ ~ 550) with large image fields of view (S: $4^{\circ}.0{\times}4'.6$, L: $7^{\circ}.5{\times}4'.3$, angular resolution 5'-10') optimized for the observation of diffuse emission of astrophysical radiation. Comet C/2001 Q4 (NEAT) was observed with a scanning survey mode when it was located around the perihelion between 8 and 15 May 2004. Several important emission lines were detected including S I (1425, 1474 ${\AA}$), C I (1561, 1657 ${\AA}$) and several emission lines of CO $A1{\cap}-X1{\sum}+$ system in the L channel. We estimated QCO = ($2.58\;{\pm}\;0.64)\;{\times}\;1028$ s-1 from the production rate of CO 1510 ${\AA}$. We obtained L-channel image which have map size of $5^{\circ}{\times}5^{\circ}$. The image was constructed for the wavelength band of L-channel (1350-1750 ${\AA}$).We also obtained radial profile of S I, C I, CO with line fitting from central coma.

• 충청수학회지
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• 제25권1호
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• pp.65-72
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• 2012

Let T > 0 be given. Let $(C[0,T],m_{\varphi})$ be the analogue of Wiener measure space, associated with the Borel proba-bility measure ${\varphi}$ on ${\mathbb{R}}$, let $(L_{2}[0,T],\tilde{\omega})$ be the centered Gaussian measure space with the correlation operator $(-\frac{d^{2}}{dx^{2}})^{-1}$ and ${\el}_2,\;\tilde{m}$ be the abstract Wiener measure space. Let U be the space of all sequence $<c_{n}>$ in ${\el}_{2}$ such that the limit $lim_{{m}{\rightarrow}\infty}\;\frac{1}{m+1}\;\sum{^{m}}{_{n=0}}\;\sum_{k=0}^{n}\;c_{k}\;cos\;\frac{k{\pi}t}{T}$ converges uniformly on [0,T] and give a set function m such that for any Borel subset G of $\el_2$, $m(\mathcal{U}\cap\;P_{0}^{-1}\;o\;P_{0}(G))\;=\tilde{m}(P_{0}^{-1}\;o\;P_{0}(G))$. The goal of this note is to study the relationship among the measures $m_{\varphi},\;\tilde{\omega},\;\tilde{m}$ and $m$.

• Journal of the Korean Wood Science and Technology
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• 제38권2호
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• pp.124-134
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• 2010

This study was performed to evaluate the efficiency of using softwood as the sawdust medium for Lentinula edodes cultivation, effect of nutrient on the mycelial growth, spawning, the mushroom yield, and quality. The nitrogen nutrition significantly enhanced the mycelial growth of L. edodes. The glutamic acid in the L. leptolepis and P. koraiensis, and asparagine in the P. densiflora were appeared to slight increase in the mycelial growth. The vegetable oil showed very effective on the mycelial growth in the P. koraiensis sawdust medium. Carbon/nitrogen ratio of all the test was reduced after mycelial growth. The mycelial growth was exclusively dependent on reduction of carbon. The mushroom yield (32.7%) of the P. densiflora sawdust medium (carbon source: 3% active carbon, nitrogen source: 0.4% asparagines) was the best in mushroom production of L. edodes, followed by the Q. variabilis sawdust (35.4%) of the control medium. The diameter of mushroom cap was obtained from the P. densiflora sawdust (carbon source: 3% sucrose, nitrogen source: 0.4% potassium nitrate) and P. koraiensis sawdust (carbon source: 3% sucrose, nitrogen source: 0.4% potassium nitrate), and the P. koraiensis sawdust (carbon source: 3% xylose, nitrogen source: 0.4% glutamic acid, supplement: 0.05% amino acid), with values 71.5 mm, 71.5 mm and 72.1 mm, respectively. In the polypropylene bag cultivation, the weight losses of the block medium gradually increased for 80 days in the dark (13.8~16.8%) and then became stable in the range of 20.7~25.8%.

• Current Applied Physics
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• 제18권12호
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• pp.1507-1512
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• 2018

The development of an organic-based aqueous redox flow battery (RFB) using quinone as an electroactive material has attracted great attention recently. This is because this battery is inexpensive, produces high energy density, and is environment friendly in stationary electrical energy storage applications. Herein, we investigate the redox potentials and solubilities of indole-5,6-quinone and indole-4,7-quinone derivatives in terms of the substituent effects of functional groups using theoretical calculations. Our results indicate that full-site substituted derivatives of indolequinone are more useful as active materials compared to single-site substituted derivatives. In particular, our calculations reveal that the substitution of $-PO_3H_2$ and $-SO_3H$ functional groups with multiple polar bonds is very effective in increasing the activity of the aqueous RFB. As a strategy to overcome the limitation that the aqueous solubility is intrinsically low because they are organic molecules, we suggest the substitution of functional groups with multiple polar bonds to the backbones of active organic materials. Among 180 indolequinone derivatives, 17 candidates that meet the redox potential standards ($${\leq_-}0.2V$$ or $${\geq_-}0.9V$$) and eight candidates with solubility exceeding 2 mol/L are identified. Three indolequinone derivatives that satisfy both conditions are finally presented as promising electroactive candidates for an aqueous RFB.

• Preventive Nutrition and Food Science
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• 제7권3호
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• pp.245-249
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• 2002

This study was conducted to investigate the effects of fermented capsicum and a capsicum product on lipid metabolism. Fermented capsicum was prepared from red pepper puree tov three months. After 9() days of fermentation, capsaicin and dihydrocapsaicin concentrations were reduced from 24.7 and 14.7 g/mL to 15.5 and 6.45 g/mL, respectively. The capsicum product was prepared from the fermented capsicum mixed with prune extract, green tea extract, neroli extract and oligo-saccharide. Thirty-two male Sprague-Dawley rats were as- signed to four dietary groups (control, high-fat control (BE-control), high-fat-fermented capsicum (HF-S-1), high- fat-capsicum product (HF-S-2)). Plasma and hepatic lipid profiles were examined after three weeks of experimental diet. Food intakes were significantly lower in the HF-S-1 and HF-S-2 groups compared to the control group (p<0.05). The weight of perirenal fat pads was lowest in animals on the control diet (low-fat) and highest in high-fat control diet. The addition of fermented capsicum to high fat diets, HF-S-1 and HE-S-2 groups, resulted in significantly lower fat pad weights compared with the HF-control group. Both fermented capsicum (HF-S-1) and the capsicum product (HF-S-2) groups had lower plasma TG levels, atherogenic-index, and liver TG levels than the BE-control group (p <0.05). Liver TC levels were significantly lower in the HF-S-2 group than the HF-control group. The results demonstrate a hypolipidemic effect of fermented capsicum and the fermented cap-sicum product.

• 대한의용생체공학회:의공학회지
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• 제42권6호
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• pp.251-258
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• 2021

Hyaluronic acid (HA) microspheres (MSs) crosslinked with polyethylene glycol diglycidyl ether (PEGDE) are prepared using a simple fluidic device (SFD) to investigate the optimized parameters. A solution mixture of PEGDE in 2-methyl-1-propanol was prepared as a continuous phase in SFD. HA solutions of 1 wt% concentration were introduced into SFD as a discontinuous phase. The HA solution prepared by stirring for more than 48 h exhibited spherical MSs at the needle tip inside the ring cap. As the flow rate of the continuous phase increased from 0.7 to 1.9 mL/min, the diameter of the MS decreased from 173±36 ㎛ to 129±13 ㎛. Although the PEGDE concentration in the range of 0.2 to 1.8 vol% did not affect the diameter of the MS, the microstructure of MS, consisting of inner hollow void and wall, was changed. The inner void and wall size decreased and increased from 79.5 ㎛ to 57.2 ㎛ and from 10.3 ㎛ to 21.4 ㎛, respectively, with increasing PEGDE concentration from 0.2 vol% to 1.8 vol%. FT-IR peaks located around 2867 cm^-1 and 1088 cm^-1 indicated that the HA MS prepared at different PEGDE concentrations were chemically crosslinked. The HA MSs containing different PEGDE concentrations exhibited quantitative cell viability of more than 98%. L-929 cells adhered well to the HA MSs and proliferated continuously with increasing culture time to 48 h regardless of PEGDE concentration, implying that the HA MSs are clinically safe and effective.

• KSBB Journal
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• 제18권1호
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• pp.55-61
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• 2003

항균 및 항암성 물질을 탐색하기 위하여 도꼬마리 열수 추출액을 ether 및 ethylacetate를 이용하여 중성, 산성, 염기성조건에서 추출한 후, 각각의 추출물을 세균 16균주 및 곰팡이와 효모 2균주를 대상으로 항균활성을 조사하였다. Ether 중성 추출물(XE-N)은 항균효과가 가장 우수하였으며, 특히 그람 양성세균(7균주), 그람 음성세균(7균주)을 비롯하여 진균중 Cryptococcus neoformans에도 뚜렷한 항균효과를 나타내었다. XE-N 및 XEA-N을 대상으로 FDA method에 의한 항균효과를 검토한 결과, p. aeruginosa를 제외한 3균주에 대해 30 ng/mL에서도 저해효과를 나타내었다 XE-N으로부터 XE-N-S1, XE-N-S3을, Ether 산성 추출물(XE-A)로부터 XE-N-S3 을, ethylacetate 중성 추출물(XEA-N)로부터 XEA-N-S2를 항균, 항암성 물질로 정제하였으나, XE-N-S1을 제외한 다른 물질들은 빠른 시간 내에 모두 분해되었다 도꼬마리 추출물 및 정제된 생리활성물질에 대한 항암효과를 검토한 결과, HeLa 자궁암 세포에 대해서는 XE-N-S1이 가장 우수하였다. HepG2간암세포에 대한 항암효과는 XE-N-S, XE-N-S3가 우수하였고, HT29 대장암세포에 대한 항암효과는 XE-N, XE-N-S1이 우수하였다. Saos2 골육종 암세포, NCI H522 폐선 암세포, NCI H1703 폐 편평세포 암세포와 Clone M3 흑색종 암세포에 대한 항암효과는 XE-N-S1이 가장 우수하였다. LN CAP 전립선 암세포에 대한 항암효과는 XE-N-S3가 가장 우수한 효과를 나타내었다. 또한 HSF 인간 정상 피부 섬유아세포에 대한 각종 추출물 및 정제물의 세포독성을 기존의 항암제인 etoposide와 cisplatin과 비교·검토한 결과, XE-A, XEA-A 및 XEA-B가 가장 독성이 낮았으며, XE-B도 etoposide에 비해 독성이 낮았다. 한편 XE-N-S1, XE-N-S3은 etoposide보다 높은 독성을 나타내었으며, XE-A-S3은 etoposide보다는 독성이 높았으나, cisplatin보다는 낮았다.

• 한국식품저장유통학회지
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• 제5권2호
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• pp.167-171
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• 1998

Bulkogi(roast beef) seasoning stored without cap at 5$^{\circ}C$ and 23$^{\circ}C$ and within capped boule at 5$^{\circ}C$, 23$^{\circ}C$, 38$^{\circ}C$, 48$^{\circ}C$ and heat cycling(38$^{\circ}C$-1 week and 5$^{\circ}C$-1 week) and investigated sensory quality, pH, VBN, amino-N, surface color, and viable cell counts during 6 month storage. Nonpackaged Bulkogi seasoning was deteriorated by molds after 2 weeks at 23$^{\circ}C$ but did not showed any significant quality changes at 5$^{\circ}C$ for 1 month. Sensory scores of packaged sample rapidly declined with the temperature increase but chemical criteria was not significantly changed depending on temperature and storage time. Correlations between sensory scores and chemical parameters was not found, but sensory scores on color was correlated with lightness(L. value) of surface color(r=0.899). Heat cycle storage resulted in similar changes in quality to 38$^{\circ}C$ storage. Ql0 values calculated by sensory evaluation results as a quality index was 6, and the shelf-life of packaged Bulkogi seasoning was predicted 88 months at 23$^{\circ}C$.

• 한국버섯학회지
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• 제10권4호
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• pp.191-197
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• 2012

수확후 큰느타리버섯의 3주 이상 저온 저장 및 유통 중 품질 유지를 확보하기 위하여 포장 내부의 적정 산소와 이산화탄소 농도를 유지하는 MAP 기술적용 체계를 확립하고자 하였다. 이를 위하여 $1{\mu}L/L$ 1-methylcyclopropene (1-MCP, 20시간, $0^{\circ}C$)을 처리하고 방담성 $30{\mu}m$ oriented polypropylene(OPP, $1238.0cc/m^2{\cdot}day{\cdot}atm\;O_2$)필름과 미세천공(MP3, $3179.9cc/m^2{\cdot}day{\cdot}atm\;O_2$)필름으로 포장한 후 $0^{\circ}C$에 저장 3주, 4주 저장 후 3일 상온유통을 실시하고 큰느타리버섯의 색도, 경도, 이취 등 품질변화를 관찰하였다. 1-MCP 처리 후 미세천공필름 포장에 의해서 저장 기간 동안 포장재 내 산소 농도 3.6~10.9%, 이산화탄소 농도 9.0~13.8% 수준이 유지되었으며 4주 저장 + 3일 상온유통 후 무처리 OPP필름보다 갓무름과 갈변, 이취 발생이 적어 상품성을 유지하였다.