• Journal of Korean Neurosurgical Society
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• 제64권6호
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• pp.913-921
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• 2021

Objective : Accurate measurement of T1 slope (a component of T1s minus cervical lordosis [CL]) is often constrained by anatomical limitations. In this situation, efforts should be made to find the exact meaning of T1s-CL and whether there are any alternatives to it. Methods : We enrolled 117 patients who received two-level anterior cervical discectomy and fusion (ACDF). Occipital slope, C2 slope (C2s), C7 slope (C7s), T1, O-C2 angle (O-C2A), C2-7 angle (C2-7A), O-C7 angle (O-C7A), T1s-CL, C7-T1 angle (C7-T1A), and C2-7 sagittal vertical axis were measured. We determined 16° (T1s-CL) as the reference point for dividing subjects into the mismatch group and the balance group, and a comparative analysis was performed. Results : The mean value of C7-T1A was constantly maintained within 2.6° peri-operatively. In addition, C2s and T1s-CL showed the same absolute change (Δ|0.8|°). The mean values of T1s-CL of the mismatch and balance groups were 23.0° and 7.6°, respectively. The five factors with the largest differences between the two groups were as follows : C2s (Δ13.3°), T1s-CL (Δ15.4°), O-C2A (Δ8.7°), C2-7A (Δ14.7°), and segmental angle (Δ7.9°) before surgery. Only four factors showed statistically significant change between the two groups after ACDF : T1s-CL (Δ4.0° vs. Δ0.2°), C2s (Δ3.2° vs. Δ0.7°), O-C2A (Δ2.6° vs. Δ1.3°), C2-7A (Δ6.3° vs. Δ1.3°). A very strong correlation between T1s-CL and C2s was also found (r=|0.88-0.96|). Conclusion : C2s itself may be the essential key to represent T1s-CL. The amounts and directions of change of these two factors (T1s-CL and C2s) were also almost identical. The above phenomenon was re-confirmed once again through the correlation analysis.

• Progress in Superconductivity
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• 제8권2호
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• pp.193-201
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• 2007

Since the margins for the minimum quench energy and for the operating current in the superconducting magnet determine the operating regime of the magnet, a thermal stability analysis for the KSTAR superconducting magnet system is performed using 1-D Gandalf code. The result shows that the minimum quench energy is about 500 mJ/cc and the operating current margin is about 70 %. These values are larger than those of the KSTAR design criteria and the KSTAR superconducting magnet system can be operated stably under various experimental environments.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.179-179
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• 2008

$BaTiO_3$를 기본조성으로 하는 PTC 써미스터는 Curie 온도이상에서 저항이 급격히 상승하는 산화물 반도체 세라믹이다. 이러한 성질을 이용하여 degaussing 소자, 정온 발열체, 온도센서, 전류 제한소자 등 상업적으로 여러 분야에서 연구되고 있다. 또한 원가절감 등을 위하여 Ni 내부전극을 사용하여 환원 분위기에서 소결하는 칩 타입에 대한 연구가 진행되고 있다. 본 연구에서는 Sm 함량(0.1at%~1.0at%)을 달리한 $BaTiO_3$(Si, Mn, Ca) 계를 선택하여 3%$H_2/N_2$ 분위기에서 1200~$1260^{\circ}C$, 2h 소결한 후 공기 중에서 재산화 처리하고 재산화 시간에 따른 PTC 특성 변화에 대하여 고찰하였다. 재산화 온도와 시간은 각각 $800^{\circ}C$와 0.5h~10h으로 하였다. Sm 함량을 달리하여 환원 분위기에서 소결한 시편의 미세구조와 PTC 특성과의 상관관계를 관찰한 결과, 소결온도가 낮을수록 PTC 특성은 좋아졌으며, 상온 비저항은 Sm 함량이 높아질수록 낮아졌다. 또한 Sm 함량이 높아질수록 jumping ratio$(R_{max}/R_{25^{\circ}C})$는 낮아졌다. 재산화 시간에 따른 PTC 특성은 다소 떨어졌지만 소결온도에 따라 달리 나타났다. Jumping ratio$(R_{max}/R_{25^{\circ}C})$는 Sm을 0.7 at% 첨가한 계에서 재산화를 1시간 처리한 시편에서 가장 우수하였다.

• 대한의생명과학회지
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• 제2권2호
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• pp.231-240
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• 1996

인체 혈액 응고 9인자는 간에서 생성되며 461개의 아미노산으로 구성된 당 단백질이다. 따라서 인체 혈액 응고 9인자 cDNA를 찾기 위해 태아의 간(fetal liver) cDNA library를 PCR(Polymerase Chain reaction) 방법으로 screening하였으며, 그 결과 ATG개시 코돈으로부터 TAA종료 코돈까지 포함하는 1.4 kb의 9인자 cDNA를 찾았다. 또한 클론된 9인자 cDNA를 박테리아에서 발현시키기 위해 박테리아 발현 벡터인 pGEX-2T 플라스미드에 클로닝하므로써 pGEX-F9 플라스미드를 제조하였다. pGEX-F9로 형질전환된 E. coli에서 PGEX-F9의 발현을 유도하면 73 kDa 크기의 GST-factor9 융합 단백질이 다량생성되며 , 이 단백질이 혈액 응고 9인자 단백질을 함유하는 융합 단잭질임을 혈액 응고 9인자 항체를 이용한 Western blot으로 입증하였다. E. coli에서 발현된 GST-factor 9 융합 단백질은 전체 단백질의 약 20%를 차지하며 GST agarose bead를 이용한 one step purificarion 방법을 통해 GST-factor9 융합 단백질을 쉽게 분리 할 수 있다.

• Mycobiology
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• 제34권2호
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• pp.73-78
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• 2006

Inter-specific hybridization between Pleurotus pulmonarius and P. florida was attempted through PEG-induced protoplast fusion to select a fusant. The protocol for protoplast release, regeneration and fusion in these two Pleurotus species was standardized using the variables controlling the process. The mixture of mycolytic enzymes, i.e. commercial cellulase, crude chitinase and pectinase, KCl (0.6 M) as osmotic stabilizer, pH 6 of the phosphate buffer and an incubation time of 3 hours resulted in the maximum release of protoplasts from 3-day-old mycelia of P. florida ($5.3{\sim}5.75{\times}10^{7}$ protoplasts/g) and P. pulmonarius ($5.6{\sim}6{\times}10^{7}$ protoplasts/g). The isolated protoplasts of P. florida regenerated mycelium with 3.3% regeneration efficiency while P. pulmonarius showed 4.1% efficiency of regeneration. Polyethyleneglycol (PEG)-induced fusion of protoplasts of these two species resulted in 0.28% fusion frequency. The fusant produced fruiting bodies on paddy straw but required a lower temperature of crop running ($24{\pm}2^{\circ}C$) than its parents which could fruit at $28{\pm}2^{\circ}C$. The stable fusant strain was selected by testing for the selected biochemical markers i.e. Carbendazim tolerance and utilization of the lignin degradation product, vanillin.

• 한국가축번식학회지
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• 제26권1호
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• pp.33-39
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• 2002

소 체세포 핵이식 시 융합액 내 $Ca^{2+}$ 농도에 따른 융합율, 핵형의 변화, 배 발달율을 검토한 결과는 다음과 같다. 1. 융합액 내 $Ca^{2+}$ 농도를 0.05, 0.1, 0.5 및 1.0 mM로 각기 다르게 처리한 결과, 0.5와 1.0 mM의 CaC$_2$에서 융합율이 80.5 와 84.3%로 나타나 0.05 mM CaCL$_2$에서의 융합율 56.6%에 비하여 유의적(P＜0.01)으로 높았다. 2. 융합액 내 $Ca^{2+}$ 농도에 따른 재구축배의 핵형을 검토한 결과, CaCL$_2$농도 0.05와 0.1 mM 에서는 88.4와 84.0%의 난자가 PCC이후 염색질괴를 형성한 반면, 0.5와 1.0 mM 에서는 54.5와 59.3%가 PCC 형태를 거치지 않고 직접 전핵을 형성하여, $Ca^{2+}$ 농도가 증가함에 따라 PCC 형태를 거치지 않고 직접 전핵을 형성하는 난자의 비율이 증가하였다. 3. 핵이식란의 체외 발육율을 검토한 결과, 1.0 mM CaCl$_2$에서는 배반포 발육율이 30.6%로 나타난 반면, 0.1 mM CaCl$_2$에서 는 20.0%로 나타나 유의적(P＜0.05)인 차이를 나타냈다. 본 연구의 결과는 융합액 내 $Ca^{2+}$농도의 증가가 소 체세포 핵이식란의 융합율 및 배반포 발육율을 향상시킬 수 있음을 시사한다.

• 미생물학회지
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• 제26권3호
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• pp.188-196
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• 1988

유당함유 울질로부터 알코올을 생산하기 위해 Saccharomyces cerevisiae X 2180-1 A, Candida pseudotropicalis ATCC 8619와 CBS 607 사이에 속간 및 종내 원형질체 융합을 시도하였다. S. cerevisiae X2180-1A(ade rho)와 C. pseudotropicalis CBS 607 (his met)간의 속간 융합율은 $1.0\times 10^{-5}$ C. pseudotropicalis ATCC 8619와 CBS 607 사이의 종내 융합율은 $3.9\times 10^{-6}$ - $1.0\times 10^{-4}$ 이었다. 이는 bovme serum albumin, myoinositol 그리고 ergosterol을 처리하지 않고 얻어진 원형질체 융합율과 비교해서 약 2-3.5배의 증가를 보여 이들 화합물이 속간 및 종내 융합을 증진시킨 것으로 사료된다. DNA 함량, 핵염색, UV 조사에 따른 생존력 비교 그리고 형질분리 후 교잡형 출현 등을 통해서 속간 (S. cerevisiae와 C. pseudotropicalis)과 종내 ( C psemdotropica/is strains) 융합체에서 핵융합이 일어난 것을 알 수 있었다. 또한 양친형과 비교해서 알코올 생성능이 증가된 종내 융합체를 얻었다.

• Journal of Korean Neurosurgical Society
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• 제63권2호
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• pp.237-247
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• 2020

Objective : Fixation of the C1-2 segment is challenging because of the complex anatomy in the region and the need for a high degree of accuracy to avoid complications. Preoperative 3D-computed tomography (CT) scans can help reduce the risk of complications in the vertebral artery, spinal cord, and nerve roots. However, the patient may be susceptible to injury if the patient's anatomy does not match the preoperative CT scans. The intraoperative 3D image-based navigation systems have reduced complications in instrument-assisted techniques due to greater accuracy. This study aimed to compare the radiologic outcomes of C1-2 fusion surgery between intraoperative CT image-guided operation and fluoroscopy-guided operation. Methods : We retrospectively reviewed the radiologic images of 34 patients who underwent C1-2 fusion spine surgery from January 2009 to November 2018 at our hospital. We assessed 17 cases each of degenerative cervical disease and trauma in a study population of 18 males and 16 females. The mean age was 54.8 years. A total of 139 screws were used and the surgical procedures included 68 screws in the C1 lateral mass, 58 screws in C2 pedicle, nine screws in C2 lamina and C2 pars screws, four lateral mass screws in sub-axial level. Of the 34 patients, 19 patients underwent screw insertion using intraoperative mobile CT. Other patients underwent atlantoaxial fusion with a standard fluoroscopy-guided device. Results : A total of 139 screws were correctly positioned. We analyzed the positions of 135 screws except for the four screws that performed the lateral mass screws in C3 vertebra. Minor screw penetration was observed in seven cases (5.2%), and major pedicle screw penetration was observed in three cases (2.2%). In one case, the malposition of a C2 pedicle screw was confirmed, which was subsequently corrected. There were no complications regarding vertebral artery injury or onset of new neurologic deficits. The screw malposition rate was lower (5.3%) in patients who underwent intraoperative CT-based navigation than that for fluoroscopy-guided cases (10.2%). And we confirmed that the operation time can be significantly reduced by surgery using intraoperative O-arm device. Conclusion : Spinal navigation using intraoperative cone-beam CT scans is reliable for posterior fixation in unstable C1-2 pathologies and can be reduced the operative time.

• Preventive Nutrition and Food Science
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• 제17권3호
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• pp.184-191
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• 2012

The purpose of this study was to investigate the fatty acid profiles in 18 soybean cultivars grown in Korea. A total of eleven fatty acids were identified in the sample set, which was comprised of myristic (C14:0), palmitic (C16:0), palmitoleic (C16:1, ${\omega}7$), stearic (C18:0), oleic (C18:1, ${\omega}9$), linoleic (C18:2, ${\omega}6$), linolenic (C18:3, ${\omega}3$), arachidic (C20:0), gondoic (C20:1, ${\omega}9$), behenic (C22:0), and lignoceric (C24:0) acids by gas-liquid chromatography with flame ionization detector (GC-FID). Based on their color, yellow-, black-, brown-, and green-colored cultivars were denoted. Correlation coefficients (r) between the nine major fatty acids identified (two trace fatty acids, myristic and palmitoleic, were not included in the study) were generated and revealed an inverse association between oleic and linoleic acids (r=-0.94, p<0.05), while stearic acid was positively correlated to arachidic acid (r=0.72, p<0.05). Principal component analysis (PCA) of the fatty acid data yielded four significant principal components (PCs; i.e., eigenvalues>1), which together account for 81.49% of the total variance in the data set; with PC1 contributing 28.16% of the total. Eigen analysis of the correlation matrix loadings of the four significant PCs revealed that PC1 was mainly contributed to by oleic, linoleic, and gondoic acids, PC2 by stearic, linolenic and arachidic acids, PC3 by behenic and lignoceric acids, and PC4 by palmitic acid. The score plots generated between PC1-PC2 and PC3-PC4 segregated soybean cultivars based on fatty acid composition.

• 한국수소및신에너지학회논문집
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• 제26권5호
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• pp.402-408
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• 2015

In D-T fusion reaction, $D_2$ (duterium) and $T_2$(tritium) are used as fuel gas. The exhaust gas of nuclear fusion includes hydrogen isotopes $Q_2$ (Q means H, D or T), tritiated components ($CQ_4$ and $Q_2O$), CO, $CO_2$, etc. All of hydrogen isotopes should be recovered before released to the atmosphere. This study focused on the recovery of hydrogen isotopes from $CQ_4$ and $Q_2O$. Two kinds of experiments were conducted to investigate the catalytic reaction characteristics of SMR (Steam Methane Reforming) and WGS (Water Gas Shift) reactions using Pt catalyst. First test was performed to convert $CH_4$ into $H_2$ using 6% $CH_4$, 6% CO/Ar feed gas. In the other test, 100% CO gas was used to convert $H_2O$ into $H_2$ at various reaction conditions (reaction temperature, S/C ratio, GHSV). As a result of the first test, $CH_4$ and CO conversion were 41.6%, 57.8% respectively at $600^{\circ}C$, S/C ratio 3, GHSV $2000hr^{-1}$. And CO conversion was 72% at $400^{\circ}C$, S/C ratio 0.95, GHSV $333hr^{-1}$ in the second test.