• Polymer(Korea)
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• v.37 no.5
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• pp.571-578
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• 2013

Polyamide12 (PA12) is blended with ethylene propylene diene rubber (EPDM) at various compositions in the presence of maleated EPDM (mEPDM) to afford blend materials having the characteristics of thermoplastic elastomer (TPE). The EPDM/PA12 melt-blends are further irradiated with electron-beam (e-beam) at 0~100 kGy dosage, yielding selective crosslinking between EPDM chains while retaining melt-processibility originated from PA12 phase. mEPDM acts as a compatibilizer and affords additional improvements in mechanical properties of the EPDM/PA12 blend. With 25 kGy of e-beam irradiation and mEPDM, the EPDM/PA12 blends successfully exhibit TPE behaviors with reasonable elastomeric and mechanical properties.

• Analytical Science and Technology
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• v.11 no.2
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• pp.130-134
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• 1998

Polyamines were analyzed in young cotyledons of spring radish. The uptake rate of SPD were transported within 20 min lineary and reached the saturation phase after 1hr. The uptake rate of SPD decreased gradually with the time by the increasing amount of SPD inside the cells. The uptake of PA depends on the external pH. The optimal pH of PA uptake are pH 7.5. $K_m-$ and $V_{max}-$values depend on external pH also. The uptake rate of PA was inhibited by external KCI, which depolarized membrane potential in the cells.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.217-222
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• 2002

본 연구에서는 가연성 폐기물을 이용한 시설원예 난방에너지 공급시스템 개발을 위하여 대형 온실 난방이나 RPC 시설에 이용할 수 있는 왕겨와 중유 겸용연소 시스템에서 중유의 연소 및 성능 특성을 분석하고자 하였다. 중요 인자로는 분사노즐의 크기(2.0, 2.25, 2.5, 3.0 GPH)와 진공압력(375, 500, 625, 750 Pa)을 설정하였으며 이에 대한 결과를 요약하면 다음과 같다. 1.진공압력 500Pa조건에서 연료 공급율이 증가할수록 연소실 벽체 열교환기 효율은 감소하고 폐열회수 열교환기와 사이클론 열교환기의 효율이 증가하였으며, 노즐 2.5GPH에서 진공압력이 커질수록 연소실 하부의 온도가 감소하였고 연소실 상부에서는 비슷한 경향을 보였다. 2, 연소온도특성, 열효율, 배기가스 성분분석 등의 결과로 볼 때 최적의 연소 조건은 노즐 2.5GPH는 진공압력 375Pa, 노즐3.0GPH는 진공압력 500Pa과 625Pa 사이로 판단되었다. 3. 배연가스내의 대기오염 성분은 모든 실험처리에서 CO 함량은 거의 없고 SO$_2$와 NO$_{x}$의 함량 또한 일반 보일러 허용기준을 만족하는 것으로 나타났다.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3731-3736
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• 2014

Phytic acid (PA) has been reported to have positive nutritional benefits and prevent cancer formation. This study investigated the anticancer activity of rice bran PA against hepatocellular carcinoma (HepG2) cells. Cytotoxicty of PA (0.5 to 4mM) was examined by MTT and LDH assays after 24 and 48h treatment. Apoptotic activity was evaluated by expression analysis of apoptosis-regulatory genes [i.e. p53, Bcl-2, Bax, Caspase-3 and -9] by reverse transcriptase-PCR and DNA fragmentation assay. The results showed antioxidant activity of PA in Fe3+ reducing power assay ($p{\leq}0.03$). PA inhibited the growth of HepG2 cells in a concentration dependent manner ($p{\leq}0.04$). After 48h treatment, cell viability was recorded 84.7, 74.4, 65.6, 49.6, 36.0 and 23.8% in MTT assay and 92.6, 77.0%, 66.8%, 51.2, 40.3 and 32.3% in LDH assay at concentrations of 1, 1.5, 2.0, 2.5, 3.0, and 3.5mM, respectively. Hence, treatment of PA for 24h, recorded viability of cells 93.5, 88.6, 55.5, 34.6 and 24.4% in MTT assay and 94.2, 86.1%, 59.7%, 42.3 and 31.6%, in LDH assay at concentrations of 1, 2.2, 3.0, 3.6 and 4.0mM, respectively. PA treated HepG2 cells showed up-regulation of p53, Bax, Caspase-3 and -9, and down-regulation of Bcl-2 gene ($p{\leq}0.01$). At the $IC_{50}$ (2.49mM) of PA, the p53, Bax, Caspase-3 and-9 genes were up-regulated by 6.03, 7.37, 19.7 and 14.5 fold respectively. Also, the fragmented genomic DNA in PA treated cells provided evidence of apoptosis. Our study confirmed the biological activity of PA and demonstrated growth inhibition and induction of apoptosis in HepG2 cells with modulation of the expression of apoptosis-regulatory genes.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.236-241
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• 2002

진공노즐방식의 파종기로 파종작업할 경우 박과채소의 대목으로 사용되고 있는 대립종자들의 최대파종율을 얻기위하여 참박, 특토좌, 흑종호박 종자에 대한 파종시험을 실시하였다. 1) 적정한 노즐구경과 홉착부압은 참박종자가 1.5mm, 7.97kPa, 특토좌종자가 1.5mm, 10.63kPa, 흑종호박종자가 2.0mm, 5.31kPa과 1.5mm, 13.28kPa로 나타났다. 2) 최적작동조건에서 참박종자, 특토좌종자 및 흑종호박 종자의 최대 파종율은 97.6%, 98.8% 및 97.6%로 나타났다. 3) 종자가 커지고 무거워짐에 따라 노즐의 구경이 큰 것이 유리한 것으로 나타났는데, 대목으로 사용되는 종자에서는 1.5mm노즐을 범용으로 사용가능하다는 결론을 얻었다. 4) 노즐개수가 많아지면 부착압력이 낮을 경우에는 파종율에 차이가 있었지만 부착압력이 높아지게 되면 파종율의 차이는 약간 낮아졌다. 5) 참박, 특토좌, 흑종호박 종자의 최대파종율을 나타내는 흡착부압 P = η.4W/$\pi$d$^2$로 나타낼 수 있고 여유계수 η ≒ 10으로 나타났다.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.161-167
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• 2011

The soil moisture has an important effect on growth and development of highbush blueberry (HB), mainly because the root system, devoid of root hairs, is superficial. Moreover, the texture and organic matter content of Korean soil is different from the main producing counties, such as USA and Canada. To facilitate the growth and development of HB and long-term maintenance of productivity, the research related to soil moisture condition in Korea should be the priority. This study was performed to investigate the growth properties of the HB in various soil moisture conditions in order to determine the irrigation trigger point and optimum soil water potential. The texture of soil used in this experiment was loam. For the experiments, the soil was mixed with peatmoss at a rates 30% (v/v). Irrigation was scheduled at -3, -4, -5, -8, -15 and -22 kPa soil water potential then investigated leaf macronutrient, bush growth, and fruit properties. The leaf K content of HB showed the same trend in the soil water potential, but Leaf P and Mg content was highest in -5 and -22 kPa, respectively. The productivity and growth amount of HB showed the peak at the range of -4~-8 kPa as normal distribution pattern, and greatly decreased at above -15 kPa. Total dry weight and Cane diameter were highest at -4 kPa, plant width, fruit weight and yield were highest at -5 kPa, and plant height, cane number and shoot tension were highest at -8 kPa. Soluble solids content showed same trend in the soil water potential, but titratable acidity, anthocyanins and total polyphenols were not significantly different. Therefore, the optimal soil water potential for the development and a maximum production of HB were a range of -4~-8 kPa, and the recommended ideal irrigation trigger point was within -15 kPa.

• The Korean Journal of Pain
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• v.3 no.2
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• pp.119-124
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• 1990

Reiestad and Stromskag recently introduced the interpleural installation of local anesthetic solutions as a technique for the management of postoperative pain in patients undergoing cholecystectomy, renal surgery, and breast surgery. This study was done to manage postoperative pain in the patients undergoing unilateral upper-abdominal surgery and thoracotomy. Twenty patients received 0.5% bupivacaine 20 ml with epinephrine (Children, received 10 ml). Results were as follows: 1) Analgesic effects appeared in 15.56 minutes; mean analgesic duration from the initial intrapleural injection was 10.5 hours. 2) Blood pressure increased more after the operation than before the operation. Blood pressure before injection of bupivacaine was highest (p<0.01). Heart rate was increased before injection and 10 minutes after injection of 0.5% bupivacaine (p<0.05). 3) The values of $PaCO_2$, were improved from $41.7{\pm}2.02\;mmHg$ ($PaCO_2$), $85.2{\pm}2.41\;mmHg$ ($PaO_2$) to $37.8{\pm}2.41\;mmHg$ ($PaCO_2$), $107.0{\pm}7.86\;mmHg$ ($PaO_2$) respectively (p<0.01). 4) Complication such as pneumothorax, atelectasis and CNS toxicity did not appear. 5) Intrapleural administration of local anesthetics after unilateral upper-abdominal and thoracic surgery provided a satisfactory pain control.

• Journal of the Korean Vacuum Society
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• v.6 no.3
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• pp.220-226
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• 1997

An optical intensity-type pressure sensor has been fabricated by coupling multimode optical fiber with 100 nm-Au/30 nm-NiCr/150 nm-$Si_3N_4/300 nm-SiO_2/150 nm-Si_3N_4$ optical reflection layer supported by micromachined frame-shape silicon substrate, and its characteristics was investigated. For the application of $Si_3N_4/SiO_2/Si_3N_4$ diaphragm to the optical reflection layer of the sensor, NiCr and Au films were deposited on the backside of the diaphragm by thermal evaporation , respectively, and thus optical low caused by transmission in the reflection layer could be decreased to a few percents. Dielectric diaphragms with uniform thickness were able to be also reproduced because top- and bottom-$Si_3N_4$ layer of the diaphragm could automatically stop silicon anisotropic etching. The respective pressure ranges in which the sensor showed linear optical output power-pressure characteristics were 0~126.64 kPa, 0~79. 98 kPa, and 0~46.66 kPa, and the respective pressure sensitivities of the sensor were about 20.69 nW/kPa, 26.70 nW/kPa, and 39.33 nW/kPa, for the diaphragm sizes of 3$\times$3 $\textrm{mm}^2$, 4$\times$4 $\textrm{mm}^2$, and 5$\times$5 $\textrm{mm}^2$, indicating that the sensitivity increases as diaphragm size increases.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.168-175
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• 2011

This study was conducted to examine the impacts of different soil water potentials on environmental soil properties related to the moisture injury of Korean raspberry (Rubus coreanus Miq.). Soil water potential in the plastic film house plots was differentiated from -5 to -40 kPa. Soils in the plots contained 5.6% of plant available water. Increasing soil water contents based on the changes in water potential increased soil pH and exchangeable $Ca^{2+}$ content and decreased exchangeable $K^+$ and total N contents. It also declined soil organic matter content at 9 days after water treatments. Relationship between water potential and soil water content was given as an exponential equation, y = 96.534 - 20.28In(x). In particular, when the water potential was higher than -20 kPa (27.5% of soil moisture content), it decreased chlorophyll content in the raspberry leaves, inhibited N uptake by the plant, and increased phosphorus content with increasing days after water treatment. Also, as the 7 days after water treatment at higher than -20 kPa of water potential, the root activity of the plant was significantly decreased, and trunk (top)/root (T/R) ratio of the plant markedly declined until 9 days after water supply. Carbohydrate contents in the raspberry plant leaves and roots at dormant stage were the lowest at -5 and -10 kPa of water potential plots, and it may cause winter injury to the plant.

• Journal of Embryo Transfer
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• v.32 no.4
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• pp.297-304
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• 2017

This study was designed to determine the effect of monosodium glutamate (MSG) on in vitro maturation (IVM) of oocytes and early development of parthenogenesis (PA) embryos in pigs. Each IVM and IVC medium was supplemented with various concentrations (0, 0.1, 0.5 and 5 mM) of MSG and non-essential amino acids (NEAA) depending on the experimental design. Immature pig oocytes were matured for 44 h and then oocytes reached metaphase II (MII) stage were electrically activated to induce parthenogenesis (PA). When immature oocytes were treated with MSG in the absence of NEAA during IVM, nuclear maturation (83.1-87.1%), intra-oocyte glutathione content, cumulus expansion, and cleavage (91.4-93.4%) of PA embryos were not influenced by MSG treatment at all concentrations. However, blastocyst formation of PA embryos was significantly increased by 5.0 mM MSG ($45.3{\pm}6.2%$) compared to control ($25.6{\pm}3.4%$). MSG treatment during IVM in the presence of NEAA did not show significant effect on nuclear maturation of oocytes and blastocyst formation after PA while 0.5 mM MSG ($89.3{\pm}1.9%$) decreased (P < 0.05) cleavage of PA embryos compared to 0.1 mM MSG ($94.6{\pm}1.1%$). When PA embryos were treated for 7 days with MSG during IVC, 5.0 mM MSG significantly decreased blastocyst formation ($27.8{\pm}4.9%$) compared to no treatment ($41.4{\pm}1.9%$) while no decrease in blastocyst formation was observed in 0.1 and 0.5 mM ($37.4{\pm}3.4%$ and $34.4{\pm}2.6%$, respectively). Our results demonstrated that 5 mM MSG in a NEAA-free chemically defined maturation medium showed positive effect on PA embryonic development while 5 mM MSG treatment during IVC was deleterious to PA embryonic development in pigs.