• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 춘계학술발표회논문집(2)
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• pp.965-970
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• 1995

원자력병원의 MC-50 싸이클로트론을 이용하여 표준선원용으로 사용되는 $^{54}$Mn를 $^{59}$ Co(p, $\alpha$pn) 핵반응으로 생산하고 이온교환수지법을 통하여 무담체의 $^{54}$Mn를 11.85$\mu$Ci/ $\mu$Ah의 수율로 분리하였다. 또한 $^{59}$ Co(p,$\alpha$pn)$^{54}$Mn 핵반응에 대한 여기함수를 stacked foil 방법으로 측정하였고, 그 결과 threshold energy는 27.3 MeV이었으며 41.2MeV에서 최대치의 핵반응단면적 47.4mb를 나타내었다.

• 한국수정란이식학회지
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• 제16권1호
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• pp.1-5
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• 2001

A total of 92 unfertilized human oocytes were treated with ethanol (EtOH), calcium ionophore A23187 (CI) or electric pulse (EP) for activating pronuclear formation and subsequent development. In Experiment 1, there was a significant (P=0.0001) treatment effect on the activation of unfertilized oocytes. No spontaneous activation was occurred in the control, but activation treatments induced PN formation with various efficacy. More unfertilized oocytes (UFOs) were activated after EtOH or EP treatment than after CI treatment. EP was as effective (63.6 %) as EtOH, but fragmentation was observed in 43% of UFOs activated by EP. Proportion of UFOs that formed presumptive haploid PN (2 PNs+1 PB or 1 PN +2 PBs) was 33.3, 0 and 28.6% after EtOH, CI and EP treatments, respectively. In Experiment 2, a significant (P=0.0362) effect of immature oocytes (IOs) status on activation was fecund. IOs at the GVBD-MI oocytes had higher potential to form PN than those at the GV stage or with abnormal morphology (25 vs. 77.8%). The results of this study clearly demonstrated that the treatment of 10% ethanol for 5 min effectively induced the activation of UFOs. IOs could form pronucleus with high efficacy by ethanol treatment, as long as they grew beyond the GVBD stage.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1947-1949
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• 1999

Carrier lifetime in silicon power devices caused switching delay and excessive power loss at high frequency switching. We studied transient turn-on/turn-off transient characteristics of electron irradiated and proton irradiated silicon pn junction diodes. Both the electron and proton irradiation of power devices have already become a widely used practice to reduce minority carrier lifetime locally[1]. The sample is n+p junction diode, made by ion implantation on a $20\Omega.cm$ p-type wafer. We investigated turn-on/turn-off transient & breakdown voltage characteristics by digital oscilloscope. Our data show that proton irradiated samples show better performance than electron irradiated samples.

• 대한전자공학회논문지
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• 제26권11호
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• pp.1652-1657
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• 1989

In this research, the PN junction type Si photodiodes have been fabricated on the low doped P type(Na=7x10**14 cm**-3) and N type (Nd=4x10**14cm**-3) (100) silicon substrates. We could find out that the dark current was lower in the N type substrate than in the P type substrate. Some well designed photodiodes showed relatively good optical and electronic characteristics that the dark current is lower than 5 nA at 10V of reverse bias condition, that the breakdown voltage is higher than 250V, and that the quantum efficiency is larger than 86% at the wavelength of $6328{\AA}$

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1997년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Fall 1997
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• pp.67-76
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• 1997

The seismic records of the main shock and two after shocks of the Yeongwol Earthquake are studied based on the phsase analysis. The travel time curves with 12 different possible phases are constructed to analysis the phases of the records. which were provided by KIGAM seismic network. The results of phase analysis show that 1) The main shock (Ms=4.5) shows clear Pn phase but two after shocks (Ms=4 and Ms=2.5) do not show Pn phase. 2) The Pg or PmP phases look as first arrival phase in the after shock records whose edicental distance is smaller or larger than 150 km. 3) It is very difficult to identity the phases related to the Conrad discontinuity even if the Conrad discontiuity arrival exists. 4) The record of GRE station located outside of the Kueongsan Basin shows different arrival time of Pn phase, P-S duration time and frequency compared with those of the other stations located within the Kyeongsan Basin.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제23권4호
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• pp.377-387
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• 2020

Purpose: To compare between sodium acetate (SA) and sodium chloride (SC) in parenteral nutrition (PN) with associated metabolic acidosis and neonatal morbidities in preterm infants. Methods: Preterm infants below 33 weeks gestational age, and with a birth weight under 1,301 g were enrolled and further stratified into two groups: i) <1,000 g, or ii) ≥1,000 g in birth weight. The subjects were randomized to receive PN containing SA or SC within the first day of life. The results of routine blood investigations for the first 6 days of PN were collated, and the neonatal outcomes were recorded upon discharge or demise. Results: Fifty-two infants entered the study, with 26 in each group: 29 infants had extremely low birth weight (ELBW). There were no significant differences in birth weight, gestation, sex, exposure to chorioamnionitis and antenatal steroids, surfactant doses and duration of mechanical ventilation between groups. The SA group had significantly higher mean pH and base excess (BE) from days 4 to 6 than the SC (mean pH, 7.36 vs. 7.34; mean BE -1.6 vs. -3.5 [p<0.01]), with a two-fold increase in the mean BE among ELBW infants. Significantly fewer on SA required additional bicarbonate (n=4 vs. 13, p=0.01). The rate of bronchopulmonary dysplasia (BPD) was approximately four-fold lower in SA than SC (n=3 vs. 11, p<0.01). No significant differences were observed in necrotizing enterocolitis, patent ductus arteriosus, retinopathy of prematurity, cholestatic jaundice, and mortality between groups. Conclusion: The use of SA in PN was associated with reduced metabolic acidosis and fewer BPD.

• 동의생리병리학회지
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• 제24권5호
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• pp.831-836
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• 2010

In addition to spice, black pepper (Piper nigrum Linne : PnL) has been used as herbal medicine because of its function in anti-oxidation, anti-inflammation, and anti-carcinogenesis. Recently, it has been reported that piperine, a component of PnL, inhibits adipocyte differentiation by repressing various adipogenic gene expressions. In this study, we determined whether piperine is a major constituent of PnL that confers the anti-adipogenic activity at whole genome level. Differentiation of 3T3-L1 pre-adipocytes was induced in presence of PnL extract or piperine. To compare genes that are regulated by PnL extract or piperine, we performed expression profiling using microarrays (Agilent Mouse 44k 4plex). RNA samples were labeled with Cy3 and Cy5, respectively. Labeled samples were hybridized to the microarrays. Results were filtered and cut off set p<0.05. Genes exhibiting significant differences in expression level were classified into Gene Ontology (GO)-based functional categories (http://www.geneontology.org) and KEGG (http://www.genome.jp/kegg/). Extract of PnL and its component piperine reduced lipid accumulation in 3T3-L1 cells during adipogenesis. Such anti-adipogenic activity appears to result from down-regulation of transcription factor genes involved in adipogenesis, and other genes involved in fatty acid synthesis, transport, triglyceride synthesis, and carbohydrate metabolism. These genome-wide studies lead to conclude that piperine, as a critical component of PnL, plays common role with PnL in anti-adipogenesis.

• 전자공학회논문지A
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• 제31A권12호
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• pp.100-105
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• 1994

SOI(Silicon-On-Insulator) pn 다이오드의 최적 수평길이($L_{dr}$)와 항복전압에 대한 해석적인 표현식을 n' 츠리프트 영역의 농도 및 두께, 매몰 산화막 두께의 함수로 유도하였다. 최적($L_{dr}$은 n'n접합의 수직 방향전계에 의한 항복전압과 n'np'접합으 수평방향 전계에 의한 항복전압이 같다는 조건으로부터 유도하였다. 해석적 표현식의 결과는 PISCESII를 사용한 시뮬레이션 결과와 잘 일치하였다.

• Mycobiology
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• 제35권3호
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• pp.145-149
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• 2007

The Elfvingia applanata (EA), Hericium erinaceum (HE), Grifola frondosa (GF), Pholiota nameko (PN), Pleurotus eryngii (PE), Trametes suaveolens (TS), Fomes fomentarius (FF), and Inonotus obliquus (IO) could produce the endo- (EN) and exo-biopolymer (EX) in submerged culture. The highest anti-complementary activity of the EN was exhibited by PN (49.1%), followed by HE (38.6%), TS (37.0%), and FF (33.0%), whereas the high activity of the EX was found with GF (59.8%), followed by HE (36.3%), TS (30.8%), and IO (28.8%). The EN of P. nameko (EN-PN) and EX of G. frondosa (EX-GF) were found to contain 78.6% and 41.2% carbohydrates, while 21.4% and 58.8% protein, respectively. The sugar and amino acid compositions of EN-PN and EX-GF were also analyzed in detail.

• 한국가축번식학회지
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• 제23권1호
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• pp.75-84
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• 1999

본 연구는 토끼 전핵배의 효율적인 생산을 위한 동결방법과 조건 등을 찾고자 유리화 동결 및 완만동결법으로 동결ㆍ융해 후 체외배양하여 생존율 및 발달률을 조사하였다. 과배란시킨 토끼의 난관으로부터 채란된 전핵배를 동결에 공시하였다. 유리화 동결은 동결보호제로 EFS 와 EPG-I을 완만동결시는 EPG-II를 사용하였다. 동결ㆍ융해 후 5%, 39$^{\circ}C$ $CO_2$incubator 에서 소 난관상피세포와 공배양하였다. 본 실험의 결과는 다음과 같다. 동결보존을 위하여 동결보호제에 적절한 평형시간과 독성 여부를 판단하기 위하여 전핵배를 EFS 용액에 0~5분간 평형시킨 후 부화배반포로의 발달률은 1 분 군에서 72.0%로 동결보호제에 노출시키지 않은 대조구 (84.1%)에 비하여 무해한 결과를 얻었으나, 그 이상에서는 유해한 결과를 보여 주었다. EFS 노출 후 희석제로 sucrose와 D-PBS를, sucrose 사용 없이 D-PBS 만으로 희석하였을 때 유의적인 (P＜0.05) 차이를 보이지 않았다. 동결보호제에 있어서는 독성검사 및 동결ㆍ융해 후 발달률을 보아 EFS, EPG-. EPG-II는 동결보존에 있어서 동결보호제로서의 가능성을 보여주었으며 서로간의 유의적인 (P＜0.05) 차이는 찾아볼 수 없었다. 유리화동결에 의한 전핵배의 부화배반포로 발달률은 6.1%를 나타내었고, 완만동결에 의한 부화배반포 발달률은 11.5%로서 동결방법간에는 유의적인 (P＜0.05) 차이가 없었다. 완만동결시 동결속도가 전핵배의 투명대 파열에 미치는 영향을 규명하기 위하여 동결속도 및 침지온도를 달리하여 조사하였을 때 －35$^{\circ}C$ (25%) 보다는 －85$^{\circ}C$ 0.9%) 에서 액체질소에 침지하였을 때가 투명대 파열률에 있어 유의적인 (P＜0.05) 차이를 보였다. 이상의 결과로부터 전핵배는 현 배양상태에서 유리화동결 및 완만동결에 의하여 동결보존이 가능하다고 사료되나 전핵배의 배반포로의 발달률은 다소 저조하였다. 유리화동결 및 완만동결에 의한 전핵배는 후기 단계의 수정란보다 물리적, 화학적 손상에 더욱 민감하여 생존율 및 발달률에 영향을 미친다고 사료된다.