• Journal of Plant Biotechnology
• /
• 제41권2호
• /
• pp.73-80
• /
• 2014

산화질소(nitric oxide: NO) 공여체인 $100{\mu}M$ sodium nitroprusside (SNP)를 배추 잎에 전처리한 후 이어서 $2{\mu}M$ paraquat (PQ)처리 시, PQ에 의해 유도된 산화적 손상에 대한 잎의 내성이 효과적으로 증진되었다. 24 시간 광 배양기간 동안 PQ 단독 처리구 잎에서는 생체량, 엽록소 및 단백질 함량이 현저하게 감소하였으나 PQ 노출 전에 3시간 SNP 전처리로 이들 잎 손상이 의미 있게 완화되었다. 게다가 PQ 처리에 기인된 malondialdehyde (MDA)와 $H_2O_2$ 함량 증가도 SNP 전처리에 의해 유의하게 억제되었다. 잎에서 이들 PQ 독성에 대한 SNP의 방어효과와 관련하여 ascorbate-glutathione 회로 구성 효소의 활성도 변화를 조사하였다. PQ 단독 처리구에서 APX, DHAR 및 GR 효소 활성도는 배양 6시간후에 급격히 감소되어 대조구 잎과 비교 시 각각 대조구의 19%, 50%, 39% 수준의 활성도 값을 보였다. 그러나, 이들 효소 활성도 값 감소는 SNP 전처리에 의해 현저하게 억제되어 6시간 배양 후에 PQ 단독처리구 보다 각각 5배, 2배, 1.5배 높은 값을 나타내었다. 또한, 그 이후 24시간 배양 때까지 PQ 단독 처리구보다 계속 높은 활성도를 보이면서 점차로 감소하였다. 이들 결과로부터, PQ에 노출된 배추 잎에서 SNP 전처리에 의한 ascorbate-glutathione 회로의 활성화가 $H_2O_2$의 축적을 억제하며 그로인해 PQ에 의해 유도된 산화스트레스로부터 잎을 방어하는 것으로 생각되었다. 동시에 이 들 결과는 산화질소가 배추 잎에서 PQ 스트레스에 대한 항산화 방어자로서의 역할을 하는 것을 의미한다.

• 한국토양비료학회지
• /
• 제24권1호
• /
• pp.10-16
• /
• 1991

토양개량(土壤改良)을 위한 기초자료(基礎資料)인 염기치환용량(鹽基置換容量)에 대한 토성별(土性別) 평균값 그리고 유기물(有機物)과 점토(粘土)의 상대기여도(相對寄與度)를 파악하기 위하여 화산회토를 제외(徐外)한 토양(土壤)을 대상(對象)으로 토양통(土壤統)의 단위위치별(單位位置別) 대표단면자료(代表斷面資料)(표본(標本)크기 : 3,182개(個))를 이용(利用)하여 다음과 같은 결과(結果)를 얻었다. 1. 토성별(土性別) CEC의 평균치는 사토(砂土) 2.9, 양질사토(壤質砂土) 4.7, 사양토(砂壤土) 6.7, 양토(壤土) 9.0, 미사질양토(微砂質壞土) 10.2, 식양토(埴壤土) 10.7, 사질식양토(砂質埴壤土) 8.6, 미사질식양토(微砂質埴壞土) 12.2, 미사질식토(微砂質埴土) 16.1 그리고 식토(埴土) 17.4me/100g이었다. 2. 토성별(土性別) CEC에 대(對)한 유기물(有機物)과 점토(粘土)의 중선형회귀식(重線型回歸式)과 편회귀계수(偏回歸係數)는 대체로 고도(高度)의 유의성(有意性) 나타내는 경향(傾向)이었다. 3. CEC 추정시(推定時) 사토계(砂土系) 사양토계(砂壤土系) 사토계토양(砂土系土壤)은 점토(粘土)가 유기물(有機物)보다 1.10~1.89배(培) 그리고 나머지 토양(土壤)은 유기물(有擬物)이 점토(粘土)보다 1.09~2.94배(培) 더 중요(重要)하였다. 4. 조사(調査)된 토양(土壤)에서 유기물(有機物)의 CEC는 62.9 그리고 점토(粘土)의 CEC는 24.0me/100g이었다.

• 한국환경과학회지
• /
• 제24권11호
• /
• pp.1343-1362
• /
• 2015

As a result of analysis based on the observed data for BOD, COD and TOC in order to manage non-biodegradable organics in the Geumho River, COD/BOD ratio was analyzed as the occupying predominance proportion. In this study, the classification(changes in water quality measurement : increase, equal, decrease) and measurement of BOD and COD were analyzed for trends over the past 10 years from 2005 to 2014 in the Geumho River. The Geumho River is expected to need non-biodegradable organics management because BOD was found to be reduced 61.1% and COD was found to be increased 50%. As a result of the analysis of land use, the Geumho-A is a unit watershed area of $921.13km^2$, which is the most common area that is occupied by forests. The Geumho-B is a unit watershed area of $436.8km^2$, which is the area that is highest occupied by agriculture and grass of 24.84%. The Geumho-C is a unit watershed area of $704.56km^2$ accounted for 40.29% of the entire watershed, which is the area that is occupied by urban of 15.12%. Load of non-biodegradable organics, which is not easy biodegradable according to the discharge, appeared to be increased because flow coefficient of COD and TOC at the Geumho-B were estimated larger than 1 value. The management of non-point sources of agricultural land is required because the Geumho-B watershed area occupied by the high proportion of agriculture and field. In this segment it showed to increase the organics that biodegradation is difficult because the ratio of BOD and TOC was decreased rapidly from GR7 to GR8. Thus, countermeasures will be required for this.

• 한국식품과학회지
• /
• 제24권3호
• /
• pp.199-203
• /
• 1992

한외여과를 이용하여 다시마 열수추출물로 부터 가용성 저분자량의 정미성분을 회수하는데 필요한 조건을 최적화하기 위해, 분리막 선정 및 온도, 압력, Flow rate의 영향을 고찰하였고 선정된 최적 조건하에서 한외여과와 Diafiltration을 실시하여 투과유량의 flux profile과 정미성분의 회수율을 비교하였다. 분리막은 소수성인 GR 51PP가 친수성인 FS 형태보다 높은 투과유량을 유지하였다. Flow rate의 증가에 따라서 투과유량도 증가하는 경향을 보였으나 3.7 l/min에서 한계값을 나타내었다. 한편, 압력이 높은 경우에는 Steady-state에서 투과유량이 감소하는 경향을 보였고 온도 증가에 따라서는 큰 변화는 없었다. 한외여과와 Diafiltration 실시에 따른 투과유량의 Flux profile과 전체 고형분과 정미성분의 회수율을 조사한 결과 한외여과를 실시한 경우가 비교적 높은 회수율을 보였으나 투과유량은 전반적으로 Diafiltration 보다 낮았다.

• Environmental Analysis Health and Toxicology
• /
• 제24권4호
• /
• pp.303-309
• /
• 2009

Hepatic antioxidant defense systems were examined in rats treated with tetrabromobisphenol-A (TBBPA), a brominated flame retardant, at the doses of 0, 250, 500 and 1,000 mg/kg for four weeks. Hepatic ratio of glutathione disulfide to glutathione (GSH) and levels of malondialdehyde, oxidative stress markers were not changed in rats treated with TBBPA. Hepatic expression of antioxidant enzymes including GSH peroxdiase-1 (GPX-1)/GSH reductase (GR), alpha-, mu- and pi-class glutathione-S-transferase (GST) and gamma-glutamylcysteine ligase catalytic subunit was determined using immunoblot analysis. Alpha-class GSTs, GPX-1 and GR levels were significantly decreased in rats treated with TBBPA at the dose of 500 or 1,000 mg/kg. These results show that TBBPA results in down-regulation of hepatic expression of antioxidant enzymes related with GSH, suggesting the liver in TBBPA-treated rats may be more sensitive to oxidants.

• 한국자원식물학회:학술대회논문집
• /
• 한국자원식물학회 2018년도 추계학술대회
• /
• pp.87-87
• /
• 2018

This study was conducted to investigate the effects of osmotic priming, liquid smoke (LS), sonication and modified drum priming treatments to improve the germination speed and uniformity of pepper seeds for high quality export seeds. Seeds were treated in 0.5, 1.0, 5.0, 10% LS solution only or with 100mM $K_2SO_4$ solution for 6days at $15^{\circ}C$. Sonication treatment was performed for 5, 10, and 20 minutes at an intensity of 5.2, 10.4, 15.7, 21.0, 26.1kHz in water at $15^{\circ}C$. After sonication treatment, seeds were primed with water or 100mM $K_2SO_4$ for 4days. 40, 50 and 60% seed moisture content (SMC) of hydrated seeds were incubated for 84, 96 and 108h in a container with a relative humidity of 99% at 26rpm for a modified drum priming treatments. 0.5% LS treatment with water or 100mM $K_2SO_4$ priming showed significant effects with 71% GP (9.0days MGT) and 66% GP (7.4days MGT), respective, while untreated seeds resulted in only 61% GP and 10days MGT. The healthy seed % was increased by 24% by $K_2SO_4$ priming with LS treatment compared to untreated seeds. However, sonication treatment showed less germination or no difference compared to untreated seed, regardless of intensity and treatment time. The modified drum priming treatment (108h incubation after 50% SMC hydration) significantly improved the GP (on the $4^{th}$days after sowing), germination rate (GR), and MGT to 65%, $28%{\cdot}day^{-1}$, and 3.6days, whereas untreated seed resulted only 7% GP, $17%{\cdot}day^{-1}$ GR and 5.9days MGT. Thus, modified drum priming treatment effectively improved seed germination and is considered as an industrially promising treatment methods considering the shortening of the treatment period and environment-friendly aspects.

• Plant Biotechnology Reports
• /
• 제5권4호
• /
• pp.353-365
• /
• 2011

The present study investigates the possible regulatory role of exogenous nitric oxide (NO) in antioxidant defense and methylglyoxal (MG) detoxification systems of wheat seedlings exposed to salt stress (150 and 300 mM NaCl, 4 days). Seedlings were pre-treated for 24 h with 1 mM sodium nitroprusside, a NO donor, and then subjected to salt stress. The ascorbate (AsA) content decreased significantly with increased salt stress. The amount of reduced glutathione (GSH) and glutathione disulfide (GSSG) and the GSH/GSSG ratio increased with an increase in the level of salt stress. The glutathione S-transferase (GST) activity increased significantly with severe salt stress (300 mM). The ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), catalase (CAT) and glutathione peroxidase (GPX) activities did not show significant changes in response to salt stress. The glutathione reductase (GR), glyoxalase I (Gly I), and glyoxalase II (Gly II) activities decreased upon the imposition of salt stress, especially at 300 mM NaCl, with a concomitant increase in the $H_2O_2$ and lipid peroxidation levels. Exogenous NO pretreatment of the seedlings had little influence on the nonenzymatic and enzymatic components compared to the seedlings of the untreated control. Further investigation revealed that NO pre-treatment had a synergistic effect; that is, the pre-treatment increased the AsA and GSH content and the GSH/GSSG ratio, as well as the activities of MDHAR, DHAR, GR, GST, GPX, Gly I, and Gly II in most of the seedlings subjected to salt stress. These results suggest that the exogenous application of NO rendered the plants more tolerant to salinity-induced oxidative damage by enhancing their antioxidant defense and MG detoxification systems.

• Journal of Electrochemical Science and Technology
• /
• 제11권2호
• /
• pp.172-179
• /
• 2020

The impact of effective parameters on the electrodeposition rate optimization of Au-Cu alloy at high thicknesses on the silver substrate was investigated in the present study. After ensuring the formation of gold alloy deposits with the desired and standard percentage of gold with the cartage of 18K and other standard karats that should be observed in the manufacturing of the gold and jewelry artifacts, comparing the rate of gold-copper deposition by direct and pulsed current was done. The rate of deposition with pulse current was significantly higher than direct current. In this process, the duty cycle parameter was effectively optimized by the "one factor at a time" method to achieve maximum deposition rate. Particular parameters in this work were direct and pulse current densities, bath temperature, concentration of gold and cyanide ions in electrolyte, pH, agitation and wetting agent additive. Scanning electron microscopy (SEM) and surface chemical analysis system (EDS) were used to study the effect of deposition on the cross-sections of the formed layers. The results revealed that the Au-Cu alloy layer formed with concentrations of 6gr·L^-1 Au, 55gr·L^-1 Cu, 24 gr·L^-1 KCN and 1 ml·L^-1 Lauryl dimethyl amine oxide (LDAO) in the 0.6 mA·cm^-2 average current density and 30% duty cycle, had 0.841 ㎛·min^-1 Which was the highest deposition rate. The use of electrodeposition of pure and alloy gold thick layers as a production method can reduce the use of gold metal in the production of hallow gold artifacts, create sophisticated and unique models, and diversify production by maintaining standard karats, hardness, thickness and mechanical strength. This will not only make the process economical, it will also provide significant added value to the gold artifacts. By pulsating of currents and increasing the duty cycle means reducing the pulse off-time, and if the pulse off-time becomes too short, the electric double layer would not have sufficient growth time, and its thickness decreases. These results show the effect of pulsed current on increasing the electrodeposition rate of Au-Cu alloy confirming the previous studies on the effect of pulsed current on increasing the deposition rate of Au-Cu alloy.

• 한국독어학회지:독어학
• /
• 제10집
• /
• pp.1-24
• /
• 2004

Wir leben heute in der sosenannten Wissensgesellschaft. Diese Geseilschaft kann durch den Zugang zu immensen Wissens- und Informationsbestanden sowie durch einen fruher nicht denkbaren Grad an $Akualit\"{a}t$ dieser Informationen gekennzeichnet werden Deutsche Unternehmen haben bereits erkannt, dass das Wissen ihrer Mitarbeiter den Wert eines Unternehmens $ma{\ss}geblich$ bestimmt. Deshalb fordern sie von ihren Mitarbeitern, sich immer speziellere, immer neuere Wissensinhaite bzw. Informationen immer schneller anzueignen. Dies gilt auch $f\"{u}r$ Fremdsprachen, deren Kenntnis im Prozess der weit vorangeschrittenen Internationalisierung und Globalisierung als ein wesentliches Instrument vorausgesetzt wird. Der Hangel an fremdsprachlichen $F\"{a}higkeiten$ in Betrieben wirkt sick vol allem auf ihre Kompetenz im Umgang mil einer steigenden Anzahl von $Gesch\"{a}ftskontakten$ und ihre $ausl\"{a}ndischen$ $M\"{a}rkte$ aus. D. h. er bedeutet in einer durch zunehmenden Wettbewerb bestimmten Weit Marktverluste. Unternehmen sollen Herausforderungen $bew\"{a}ltigen$, die $gro{\ss}e$ interaktive und kommunikative $F\"{a}higkeit$ erfordern, $Ver\"{a}nderungen$ zu begreifen, sich ihnen zu stollen und sie zu $\"{u}berwinden$, um erfolgreich einen $gr\"{o}{\ss}eren$ Wirkungskreis auf den $Weltm\"{a}rkten$ zv erreichen. Deutsche Unternehmen erkennen inzwischen die besondere Bedeutung von $Fremdsprachenf\"{a}higkeiten$ ihrer Mitarbeiter $f\"{u}r$ Erfdlgssicherung und -ausbau. Diese Erkenntnisse ergeben sich auch aufgrund von Unternehmensbefragungen (z.B. vom Institut der deutschen Wirtschafi, $K\"{o}ln$). In fast allen Unternehmen ist Englisch die Fremdsprache Nummer Eins. Sie brauchen allerdings mehr als eine Fremdsprache. In der Regel werden zwei bis drei Fremdsprachen pro Betrieb $ben\"{o}tigt$. Wie $gro{\ss}$ der Fremdsprachenbedarf ist, $h\"{a}ngt$ von verschiedenen Faktoren ab: 1) Je $gr\"{o}{\ss}er$ ein Betrieb ist, desto wichtiger werden die fremdsprachlichen $F\"{a}higkeiten$ seiner Mitarbeiter. 2) In Firmen mit Auslandsverbindung und Unternehmen, die Teil eines $ausl\"{a}ndischen $Betriebes sind bzw $ausl\"{a}indische$ Niederlassungen haben, ist der Fremdsprachenbedarf von $gro{\ss}er$ Bedeutung. 3) Nach Branchen ist der Fremdsprachenbedarf differenziert. Fremdsprachenkenntnisse sind im exportorientierten produzierenden Gewerbe unverzichtbar. 4) In den verschiedenen Unternehmensbereichen werden Fremdsprachenkenntnisse differenziert $ben\"{o}tigt$. Funktionsbereiche wie Verkauf und Kundenbetreuung haben den $st\"{a}rksten$ Fremdsprachenbedarf, Kommunikation ist eine wesentliche Voraussetzung $f\"{u}r$ erfolgreiche Verhandlungen. Je $gr\"{o}{\ss}er$ die sprachliche $F\"{a}higkeiten$ und das Geschick der Mitarbeiter sind, umso besser laufen die $Gesch\"{a}ftsverhandlungen$. Damit wird klar, weshalb sich viele deutsche Unternehmen beim Fremdsprachenlernen, bzw. bei der Fort- und Weiterbildung von Fremdsprachenkenntnissen ihrer Mitarbeiter spendabel zeigen.

• 한국약용작물학회지
• /
• 제26권5호
• /
• pp.370-381
• /
• 2018

Background: To enhance the taste and physiological characteristics of Lycii fructus (Gugija) extracts, we investigated the changes in the physiological characteristics of Gugija extracts caused by adding white ginseng (WG) and red ginseng (RG) Methods and Results: Gugija extracts, including 10G10, 10GW-G8 : 2, -G6 : 4, -G4 : 6, -G2 : 8, and -G0 (mixtures made by replacing 0, 20, 40, 60, 80, and 100% of Gugija with WG), as well as 10G10, 10GR-G8 : 2, -G6 : 4, -G4 : 6, -G2 : 8, and -G0 (mixture made by replacing 0, 20, 40, 60, 80, and 100% of Gugija with RG) were extracted with water at 10 times the respective mixture's volume. The antioxidant activities of Gugija extracts were investigated by assessing their 1,1-diphenyl-2-picrydrazyl (DPPH) and 2,2'-azinobis(3ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, ferric reducing antioxidant potential (FRAP) activity, nitrite scavenging activity, and angiotensin converting enzyme (ACE) inhibitory activity. As the amount of WG added increased, the DPPH, and, ABTS radical scavenging activity, and FRAP activity of the Gugija extract decreased. The half maximal inhibitory concentration ($IC_{50}$) value of 10G10, 10GW-G6 : 4, 10GR-G6 : 4, and 10GR-G0 for DPPH radical scavenging activity were $25.50{\pm}1.04$, $52.06{\pm}1.46$, $16.87{\pm}1.24$, and $9.50{\pm}0.16{\mu}{\ell}/m{\ell}$, respectively. On the other hand, the physiological activity of Gugija extract increased with the addition of increasing amounts of RG. However, ACE inhibitory activity was the highest ($50.25{\pm}2.58%$) in the Gugija 10-fold extract without any added RG. Conclusions: From the above results, we suggest that adding RG to Gugija extracts increase their antioxidant, FRAP, and nitrite scavenging activities.