• Journal of the Korean Magnetics Society
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• v.12 no.3
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• pp.88-93
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• 2002

Rapidly solidified NdFeB powders were mixed with fine powders of pure metal elements before CA-press employed to obtain a fully dense isotropic precursor. Subsequently, the precursor was deformed by CA-deformation to obtain an anisotropic magnet. The CA-deformed anisotropic NdFeB magnets with 0.3 wt.% Zn or Sn exhibited the coercivities about 80% higher (11.4. and 11.2 kOe, respectively) than that (6.4 kOe) of the additive-free magnet.

• Journal of the Korean institute of surface engineering
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• v.50 no.4
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• pp.277-281
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• 2017

Ferroelectric ceramics are broadly used for various industrial applications. In this research, the lead-free ferroelectric ceramics of $(K_{0.5}Na_{0.5})NbO_3$ was fabricated by using the solid state synthesis. The $(K_{0.5}Na_{0.5})NbO_3$ pellets were sintered at 1200, 1150 and $1100^{\circ}C$ for 4 hours in air atmosphere. Field-emission scanning electron microscopy (FE-SEM) characterization of the sintered KNN ceramics revealed surface morphology and grain size. And we used the X-ray diffraction (XRD) for measuring the sample crystal phase. Temperature dependence of the dielectric constant was measured by using an LCR meter. The sintered at $1150^{\circ}C$ for 4 hours sample has a highest dielectric constant 6011 at Curie temperature ($T_C$) and dense structure with $2.33{\mu}m$ grain size.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3247-3251
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• 2010

Molecular structures of the various conformers for the four stereoisomers of tetra-t-butyl-tetra-O-methylsulfinylcalix[4]arene (1) were optimized using DFT BLYP and mPW1PW91/6-31G(d,p) (hybrid HF-DF) calculation methods. We have analyzed the total electronic and Gibbs free energies and normal vibrational frequencies of 16 different structures from four major conformations (cone (CONE), partial cone (PC), 1,2-alternate (1,2-A), 1,3-alternate (1,3-A)) of the four stereoisomers [1(rccc), 1(rcct), 1(rctt), 1(rtct)]. The mPW1PW91/6-31G(d,p) calculations suggested that the $1(rccc)_{CONE}$, $1(rcct)_{PC}$, $1(rctt)_{PC}$, and $1(rtct)_{1,3-A}$ were the most stable conformations of the respective stereoisomers. These outcomes are in accordance with the experimental structures obtained from X-ray crystallography. The electrostatic repulsion between the sulfinyl and methoxy groups is a primary factor for the relative stabilities of the four different conformations. The IR spectra of the most stable conformers [$1(rccc)_{CONE}$, $1(rcct)_{PC}$, $1(rctt)_{PC}$, $1(rtct)_{1,3-A}$] of each stereoisomer were compared to each other.

• Preventive Nutrition and Food Science
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• v.2 no.3
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• pp.250-254
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• 1997

The internal invertase of Rhodosporidium toruloids mating type a cells was purified to a single band on SDS-PAGE from cell-free extract by acid precipitation, ion exchange chromatogaphy andgel filtration. The determined molecular weight of he purified enzyme was about 95,000 by gel filtration and 100,000 daltons on SDS-polyacryamide gel electrophoresis. This enzyme didn't show any activity change by several metal ions except 15.4% decrease by {TEX}$Mn^{2+}${/TEX} and was strongly inhibited by 2-mercaptoethanol and SDS. The invertase maintained its activity at high level until 70℃, but inactivated at 80℃ almost completely. The optimal temperature and pH of the enzyme were about 60℃ and pH 5.0, respectively. The stable pH range of invertase was narrow from pH 3.0 to 6.0. The Km value and isoelectric point of enzyme were 3.4×{TEX}$10^{3}${/TEX} M, pH 4.4, respectively.

• Proceedings of the Ginseng society Conference
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• 2002.10a
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• pp.288-297
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• 2002

In this paper, we present evidence that the red ginseng from Panax ginseng C.A. Meyer inhibits the recurrence of advanced gastric cancer and shows immunomodulatory activities during postoperative chemotherapy. Flow cytometric analyses for peripheral T-lymphocyte subsets showed that the red ginseng powder restored CD4 levels to the initial preoperative values during postoperative chemotherapy. Depression of CD3 during postoperative chemotherapy was also inhibited by the red ginseng powder ingestion. This study demonstrated a 5-year disease free survival and overall survival rate that was significantly higher in patients taking the red ginseng powder during postoperative chemotherapy vs. control $(68.2\%\;vs.\;33.3\%,\;76.4\%\;vs.\;38.5\%,$ respectively, p<0.05). The mean value of serum IL-10 of the ginseng group was reduced progressively during the postoperative chemotherapy. The values of the ginseng group were close to that of the control group on postoperative months 3. These studies suggest that the red ginseng may have some immunomodulatory properties associated with CD3 and CD4 activity and interleukin 10 during postoperative chemotherapy and some potential of improving prognosis in patients with advanced gastric cancer.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.674-679
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• 2008

Scutellaria radix (SR) has been utilized as a traditional medicine for a variety of diseases including Rheumatoid arthritis and its major flavonoids - baicalein, baicalin, and wogonin - have been reported to exert beneficial health effects, including anti-bacterial, anti-viral, anti-inflammatory, and free-radical scavenging. However, the mechanisms underlying this effect remain poorly understood. The principal objective of this study was to determine the effect of SR on osteoblast and osteoclast cells. SR extract was prepared using 70% ethanol solvent. Osteoblastic MC3T3-E1 cells and osteoclast precursor Raw 264.7 macrophage cells were utilized. SR extract increased MC3T3-E1 cell proliferation and stimulated alkaline phosphatase activity dose-dependently, 152.0% of the control at concentration $1{\mu}g/mL$. Additionally, SR extract ($1{\mu}g/mL$) stimulated Bone nodule formation activity in MC3T3-E1 cells, approximately 223.3% of the control, 20 days after the exposure. In addition, SR extract significantly reduced the number of tartrate-resistant acid phosphatase-positive (TRAP+) multinucleated cells from Raw 264.7 cells. In conclusion, SR extract stimulates the proliferation and bioactivities of boneforming osteoblasts, and inhibits the activities of bone-resorbing osteoclasts to a certain degree.

• Radiation Oncology Journal
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• v.26 no.3
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• pp.142-148
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• 2008

Purpose: We analyzed the treatment outcomes and prognostic factors of breast conserving surgery, followed by postoperative radiotherapy.Materials and Methods: A total of 424 breast cancer patients treated with breast conserving surgery and postoperative radiotherapy between February 1992 and January 2001 were retrospectively analyzed. A quadrantectomy and axillary lymph node dissection was performed in 396 patients. A total of 302 patients had T1 disease, and 122 patients had T2 disease. Lymph node involvement was confirmed in 107 patients. Whole breast irradiation was administered at up to 50.4 Gy in 28 fractions, followed by a 10 Gy boost in 5 fractions to the tumor bed. In addition, 57 patients underwent regional lymph node irradiation. Moreover, chemotherapy was administered in 231 patients. A regimen consisting of cyclophosphamide, methotrexate, and 5-fluorouracil was most frequently used with 170 patients. The median follow-up time was 64 months. Results: The 5-year local control rate was 95.6%. During the follow-up period, local tumor recurrence was observed in 15 patients. The 5-year overall and disease-free survival rates were 93.1% and 88.7%, respectively. The 5-year overall survival rates, by stage, were 94.8% for stage I, 95.0% for stage IIA, 91.1% for stage IIB, 75.9% for stage IIIA, and 57.1% for stage IIIC. As for disease-free survival, the corresponding figures, by stage (in the same order), were 93.1%, 89.4%, 82.8%, 62.0%, and 28.6%, respectively. The advanced N stage (p=0.0483) was found to be a significant prognostic factor in predicting poor overall survival, while the N stage (p=0.0284) and age at diagnosis (p=0.0001) were associated with disease-free survival. Conclusion: This study has shown that breast conserving surgery and postoperative radiotherapy for early breast cancer results was excellent for local control and survival.

• Journal of the Korean Society of Radiology
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• v.18 no.2
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• pp.73-81
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• 2024

This study compared the cortical thickness of patients with mood disorders and a control group to assess structural abnormalities. A retrospective study was conducted from September 2020 to August 2022 at the Department of Psychiatry, P Hospital in Yangsan, Gyeongsangnam-do. The study included 44 individuals diagnosed with mood disorders and 59 healthy individuals without any pathological lesions. The 3D-T1 MPRAGE images obtained from magnetic resonance imaging examinations were utilized, and FreeSurfer software was employed to measure cortical thickness. Statistical analysis involved independent samples t-tests to measure the differences in means between the two groups, and Cohen's d test was used to compare the effect sizes of the differences. Furthermore, the correlation between the measured average cortical thickness and Positive and Negative Syndrome Scale scores was analyzed. The research results revealed that patients with mood disorders exhibited decreased cortical thickness compared to the normal control group in both superior frontal regions, both rostral middle frontal regions, both caudal middle frontal regions, both pars opercularis, pars orbitals, pars triangularis regions, both superior temporal regions, both inferior temporal regions, both lateral orbitofrontal regions, both medial orbitofrontal regions, both fusiform regions, both posterior cingulate regions, both isthmus cingulate regions, both superior parietal regions, both inferior parietal regions, both supramarginal regions, left postcentral region, right bank of the superior temporal sulcus region, right middle temporal region, right rostral anterior cingulate region, and right insula region. Among them, regions that showed differences with effect sizes of 0.8 or higher were left fusiform (d=0.82), pars opercularis (d=0.94), superior frontal (d=0.88), right lateral orbitofrontal (d=0.85), and pars orbitalis (d=0.89). Additionally, there was a weak negative correlation between PANSS scores and average cortical thickness in both the left hemisphere (r=-0.234) and right hemisphere (r=-0.230). These findings are expected to be helpful in identifying areas of cortical thickness reduction in patients with mood disorders compared to healthy individuals and understanding the relationship between symptom severity and cortical thickness changes.

• Investigative Magnetic Resonance Imaging
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• v.11 no.1
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• pp.39-48
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• 2007

Purpose : To determine the diagnostic accuracy of four different sequences : moderately T2 weighted, two heavily T2-weighted single shot turbo spin-echo sequence and breath-hold axial-2D balanced turbo field-echo sequence(bFFE) for characterization of focal lesions. Materials and Methods : During the 3-month period between June and August 2005, seventy-six patients were proved to have ninety-three focal hepatic lesions on MR imaging. The patients consisted of 49 men and 27 women (age range, 15-75 years; mean age, 56.23 years). All MR images were acquired on a 1.5-T MR using the following sequences: 1. A breath-hold axial T2-weighted single shot turbo spin-echo sequence, 2. a breath-hold axial-2D balanced turbo field-echo sequence. Two radiologists performed quantitative analysis. Another radiologist measured the lesion-to-liver contrast-to-noise ratio at the region-of-interest in the four sequences. Results : There was no significant difference in inter-observer variability between the four sequences. The accuracy for both cyst and malignancy of moderate T2 weighted MRI (echo time: 80 msec) was also highest. There was significant difference for lesion characterization between moderate T2 weighted MRI and balanced steady state procession (p-value: 0.004) in the second reader. For longer echo time, the CNR of cystic lesions were markedly increased in comparison to lesions of other component. Conclusion : The accuracy and inter-observer variability of single shot turbo spin echo T2 weighted sequence was higher than bFFE. Although there was no statically significant difference, moderate T2 weighted MRI (echo time: 80 msec) was more accurate than heavily T2 weighted sequence (echo time: 300 msec). If the results for lesion characterization is equivocal in TE 80, the addition of heavily T2 weighted MRI (echo time: 180 msec) can be helpful.

• Journal of Chest Surgery
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• v.39 no.5 s.262
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• pp.354-358
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• 2006

Background: Pulsatile pumps for extracorporeal circulation have been known to be better for tissue perfusion than non-pulsatile pumps but be detrimental to blood corpuscles. This study is intended to examine the risks and benefits of $T-PLS^{TM}$ through the comparison of clinical effects of $T-PLS^{TM}$ (pulsatile pump) and $Bio-pump^{TM}$ (non-pulsatile pump) used for coronary bypass surgery. Material and Method: The comparison was made on 40 patients who had coronary bypass using $T-PLS^{TM}\;and\;Bio-pump^{TM}$ (20 patients for each) from April 2003 to June 2005. All of the surgeries were operated on pump beating coronary artery bypass graft using cardiopulmonary extra-corporeal circulation. Risk factors before surgery and the condition during surgery and the results were compared. Result: There was no significant difference in age, gender ratio, and risk factors before surgery such as history of diabetes, hypertension, smoking, obstructive pulmonary disease, coronary infarction, and renal failure between the two groups. Surgery duration, hours of heart-lung machine operation, used shunt and grafted coronary branch were little different between the two groups. The two groups had a similar level of systolic arterial pressure, diastolic arterial pressure and mean arterial pressure, but pulse pressure was measured higher in the group with $T-PLS^{TM}\;(46{\pm}15\;mmHg\;in\;T-PLS^{TM}\;vs\;35{\pm}13\;mmHg\;in\;Bio-pump^{TM},\;p<0.05)$. The $T-PLS^{TM}$-operated patients tended to produce more urine volume during surgery, but the difference was not statistically significant $(9.7{\pm}3.9\;cc/min\;in\;T-PLS^{TM}\;vs\;8.9{\pm}3.6\;cc/min\;in\;Bio-pump^{TM},\;p=0.20)$. There was no significant difference in mean duration of respirator usage and 24-hour blood loss after surgery between the two groups. Plasma free Hb was measured lower in the group with $T-PLS^{TM}\;(24.5{\pm}21.7\;mg/dL\;in\;T-PLS^{TM}\;versus\;46.8{\pm}23.0mg/dL\;in\;Bio-pump^{TM},\;p<0.05)$. There was no significant difference in coronary infarction, arrhythmia, renal failure and morbidity rate of cerebrovascular disease. There was a case of death after surgery (death rate of 5%) in the group tested with $T-PLS^{TM}$, but the death rate was not statistically significant. Conclusion: Coronary bypass was operated with $T-PLS^{TM}$ (Pulsatile flow pump) using a heart-lung machine. There was no unexpected event caused by mechanical error during surgery, and the clinical process of the surgery was the same as the surgery for which $Bio-pump^{TM}$ was used. In addition, $T-PLS^{TM}$ used surgery was found to be less detrimental to blood corpuscles than the pulsatile flow has been known to be. Authors of this study could confirm the safety of $T-PLS^{TM}$.