• Radiation Oncology Journal
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• v.17 no.4
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• pp.299-306
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• 1999

Purpose : The human genetic disorder ataxia-telangiectasia (AT) is a multisystem disease characterized by extreme radiosensitivity. The recent identification of the gene mutated in AT, ATM, and the demonstration that it encodes a homologous domain of phosphatidylinositol 3-kinase (PI3-K), the catalytic subunit of an enzyme involved in transmitting signals from the cell surface to the nucleus, provide support for a role of this gene in signal transduction. Although ionizing radiation was known to induce c-fos transcription, nothing is known about how ATM or PKCI mediated signal transduction pathway modulates the c-fos gene transcription and gene expression. Here we have studied the effect of PKCI on radiation sensitivity and c-fos transcription in normal and AT cells. Materials and Methods: Normal (LM217) and AT (AT5BIVA) cells were transfected with PKCI expression plasmid and the overexpression and integration of PKCI was evaluated by northern blotting and polymerase chain reaction, respectively. 5 Gy of radiation was exposed to LM and AT cells transfected with PKCI expression plasmid and cells were harvested 48 hours after radiation and investigated apoptosis with TUNEL method. The c-fos transcription activity was studied by performing CAT assay of reporter gene after transfection of c-fos CAT plasmid into AT and LM cells. Results: Our results demonstrate for the first time a role of PKCI on the radiation sensitivity and c-fos expression in LM and AT cells. PKCI increased radiation induced apoptosis in LM cells but reduced apoptosis in AT cells. The basal c-fos transcription activity is 70 times lower in AT cells than that in LM cells. The c-fos transcription activity was repressed by overexpression of PKCI in LM cells but not in AT cells. After induction of c-fos by Ras protein, overexpression of PKCI repressed c-fos transcription in LM cells but not in AT cells Conclusion: Overexpression of PKCI increased radiation sensitivity and repressed c-fos transcription in LM cells but not in AT cells. The results may be a. reason of increased radiation sensitivity of AT cells. PKCI may be involved in an ionizing radiation induced signal transduction pathway responsible for radiation sensitivity and c-fos transcription. The data also provided evidence for novel transcriptional difference between LM and AT cells.

• Journal of Gifted/Talented Education
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• v.23 no.5
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• pp.751-769
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• 2013

This study aims to compare the difference between the recognition of professionalism and teaching efficacy of the gifted education teacher by majoring in education for the gifted from the graduate school. The subjects were 44 graduate students in gifted education major and 56 gifted education teachers of elementary school who did not major in the education for the gifted. The results were as follows. First, the education for the gifted children majors showed higher statistical significance in the subject knowledge, the instructional strategies, the understanding gifted student, personal efficacy and outcome expectancy than the teacher who did not major in the education for the gifted children (p<.05). Second, in the results of Two-Way ANOVA by the major status in education for the gifted children and the gender, there was the interaction effects in the subject knowledge, the understanding gifted student, personal efficacy, and the females were influenced by the recognition of professionalism and teaching efficacy by the major status in education for the gifted children more than males. In the results of analysis on the major status in education for the gifted children and career for gifted education, the instructional strategies and personal efficacy showed the significant interaction effect (p<.05). Third, in the results of analysis on the relations between the recognition of professionalism and the teaching efficacy, all subordinate scopes of the recognition of professionalism and teaching efficacy showed the significant positive correlation (p<.05). In the results of the multiple regression analysis, the subject knowledge and the instructional strategies have effects on the personal efficacy. So the majoring in education for the gifted children from the graduate school may have significant effects on development of the subject knowledge and the professionality of the instructional strategies of the gifted education teacher, further, it can be said that has positive effect on teaching efficacy.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.241-247
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• 2013

AOAC Mouse Bioassay Analysis (MBA) has been the gold standard for the analysis of paralytic shellfish poisoning toxin (PSP toxin) for more than 50 years. However, this method has inaccurate limit of quantification and cannot be used to determine toxic profiles. An HPLC method (PCOX) was optimized for Korean shellfish to establish an alternative or supplementary method for PSP analysis and was intended to be used for the official monitoring and regulation of food. The recovery rate of the PCOX method was 83.5-112.1% and the limit of quantification for total toxin was about $8.6{\mu}g$/100 g. A long-term comparison study showed a good correlation of the PCOX results with the AOAC MBA results: the correlation factors were 0.9534 and 0.9109 for oyster and mussel matrices, respectively. The PCOX method may be used as an alternative or supplementary method for AOAC MBA to monitor the occurrence of PSP and to analyze PSP toxin profile in oysters and mussels.

• Journal of the Korean Society of Radiology
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• v.6 no.1
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• pp.73-77
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• 2012

Recently, Interest to the photoconductor, which is used to flat form X-ray detector such as a-Se, $HgI_2$, PbO, CdTe, $PbI_2$ etc. is increasing. In this study, the film layer by using the photoconductive material with particle sedimentation was fabricated and evaluated. The quantization efficiency of the continuous X-ray with the 70 kVp energy bandwidth was analyzed by using the Monte Carlo simulation. With the results, the thickness of film with 64 % quantization efficiency was 180 ${\mu}m$ which is similar to the efficiency of 500 ${\mu}m$ a-Se film. And $HIg_2$ film has the high quantization efficiency of 74 % on 240 ${\mu}m$ thickness. The electrical characteristics of the 239 ${\mu}m$ $Hgl_2$ films produced by particle sedimentation were shown as very low dark current(under 10 $pA/mm^2$), and high sensitivity(19.8 mC/mR-sec) with 1 $V/{\mu}m$ input voltage. The SNR, which is influence to the contrast of X-ray image, was shown highly as 3,125 in low driving voltage on 0.8 $V/{\mu}m$. With the results of this study, the development of the low-cost, high-performance image detector with film could be possible by replacing the film produced by particle sedimentation instead to a-Se detector.

• Korean Journal of Food Science and Technology
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• v.40 no.1
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• pp.8-14
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• 2008

This study was performed to establish analysis methods, and evaluated for grayanotoxin in domestic/foreign honey and wild honey. The molecular weight of grayanotoxins I, II and III, excluding grayanotoxin III that has been commercialized, were analyzed by LC-MS/MS. Then, the molecular structure of grayanotoxins I and II were analyzed by NMR. A total 111 samples (25 Korean honey, 21 Korean wild honey, 13 Korean honeycomb honey, 44 foreign honey, 8 foreign wild honey) were examined to determined whether or not each sample contained grayanotoxins I, II, and III. The honey samples were mixed with methanol and loaded into a tC18 cartridge, the filtrate was diluted with water, and the mixture was then analyzed by ESI triple-quadrupole LC-MS/MS. Grayanotoxins were only found in the foreign wild honey and were not detected in Korean honey, Korean honeycomb honey, or Korean wild honey. Three of the samples contained grayanotoxin I, II, and III, and one sample contained only grayanotoxins I and III. The lowest level for grayanotoxin I was 3.13 ${\pm}$ 0.00 mg/kg, and the highest level was 12.93 ${\pm}$ 0.01 mg/kg. The levels of grayanotoxin II were 0.84 ${\pm}$ 0.01 mg/kg, 0.92 ${\pm}$ 0.00 mg/kg and 1.08 ${\pm}$ 0.01 mg/kg, respectively. The lowest level of grayanotoxin III was 0.25 ${\pm}$ 0.01 mg/kg and the highest level was 3.29 ${\pm}$ 0.74 mg/kg. Through this study, safety management for foreign wild honey has been enabled.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.236-246
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• 2004

Artificial carious lesions in various depths were observed with visual examination using light transillumination, bite-wing radiography, laser fluorescence, and dye-enhanced laser fluorescence to determine the reproducibility, correlation of each diagnostic method, diagnostic sensitivity and diagnostic specificity. And optical densities according to demineralized times were measured whether laser fluorescence could be used as a quantitative diagnostic method. The following results were obtained whether laser fluorescence could be used for diagnosis of initial proximal caries. 1. Tau-c values of visual examination was 0.08 which showed lowest reproducibility and those of bite-wing radiography, laser fluorescence, dye-enhanced laser fluorescence were 0.60, 0.48, and 0.64, respectively which showed relatively high reproducibility. 2. The correlation between demineralization time and each examination was the highest in dye-enhanced laser fluorescence$({\gamma}=0.51)$ followed by laser fluorescence$({\gamma}=0.43)$, bite-wing radiograph$({\gamma}=0.35)$, and visual examination$({\gamma}=0.33)$. Dye-enhanced laser fluorescence and laser fluorescence showed significant correlation with demineralization time. 3. The sensitivity of laser fluorescence and dye-enhanced laser fluorescence for diagnosing approximal caries based on bite-wing radiography were 67%, 100% and those of specificity were 57%, 11% which showed diagnostic specificity was relatively lower than sensitivity. 4. The difference in optical density(DFR) between sound teeth and carious lesions according to lesion depth was high with dye-enhanced laser fluorescence compared with laser fluorescence. DFR measured with laser fluorescence according to changes in lesion depth was statistically significant but was not statistically significant with dye-enhanced laser fluorescence. Based on these results, laser fluorescence and dye-enhanced laser fluorescence have comparable diagnostic power as bite-wing radiography in early diagnosis of proximal caries.

• Journal of The Korean Ophthalmological Society
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• v.58 no.3
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• pp.321-326
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• 2017

Purpose To identify the correspondence between the central sensitivity of several visual field (VF) tests and ganglion cell inner plexiform layer (GC-IPL) thickness in early glaucoma patients with parafoveal scotoma. Methods Fifty-seven eyes from 57 patients with glaucomatous optic neuropathy and parafoveal scotoma were analyzed using the standard automated perimetry (SAP) C10-2 test, the SAP C24-2 test, and the frequency doubling technology perimetry (FDT) C24-2 test. The correlation between the VF central sensitivity and the GC-IPL thickness from macular scans via optical coherence tomography was analyzed. Results The central sensitivity was $27.51{\pm}5.43dB$, $27.39{\pm}5.05dB$, and $22.09{\pm}5.08dB$ for SAP C24-2, SAP C10-2, and FDT C24-2, respectively. Mean GC-IPL thickness was $70.2{\pm}8.5{\mu}m$. Using regression analysis, the value of log $R^2$ between the logarithmic central sensitivity and GC-IPL thickness was 0.498, and the linear $R^2$ between the antilogarithmic central sensitivity and GC-IPL thickness in SAP C10-2 was 0.486, and both were statistically significant (p < 0.05). This relationship was stronger in early glaucoma patients compared to late glaucoma patients using SAP C10-2. Conclusions The structure-function relationship between GC-IPL thickness and central sensitivity was better with SAP C10-2, especially in early glaucoma patients, compared to other VF modalities.

• Proceedings of the Mineralogical Society of Korea Conference
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• 2001.06a
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• pp.141-142
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• 2001

남서부 경기육괴의 편마암류로부터 분리된 저어콘(zircon) 입자를 대상으로, 이온현미분석기(ion microprobe)를 사용한 U-Pb 연대를 구하였다. 그 결과는 후기 원생대(약 820 Ma) 뿐만 아니라 오르도비스기에 상당한 화성활동이 한반도에 있었음을 지시한다. 우리 나라 후기 원생대의 화성-변성 활동에 대해 알려져 있는 바는 극히 제한적이어서 후속연구가 필수적이며, 이러한 연구는 한반도의 지체구조적 변천사를 로디니아 초대륙(Rodinia supercontinent)의 생성-분리와 관련해 재조명할 수 있는 기회를 제공할 것이다. 또한 오르도비스기의 화성작용은 그동안 논란이 되어 왔던 소위 “칼레도니아(Caledonian)” 변동 (cf. 조문섭, 2000)에 대한 또 다른 증거를 제공해준다. 저어콘의 연대측정은 서호주의 커튼공업대학교에 설치되어 있는 SHRIMP-II(Sensitive High-Resolution Ion Microprobe-II; 고감도-고분해능 이온현미분석기)를 사용하였으며, 시료 준비 및 분석방법은 기존에 보고된 바와 같다 (e.g., Kinny et al., 1999). 분석된 3개의 암석 시료(1006-5, 8, 9)는 경기육괴의 남서부에 위치한 홍성 지역의 정편마암들이다. 1006-8 시료는 Turek and Kim (1996)이 전통적인 방법을 사용해 687$\pm$5 Ma의 U-Pb 저어콘 연대를 보고한 바 있는 화강암질 편마암 (시료번호, KJ43)에 해당된다. 두 개의 다른 시료는 1006-8 주변에서 산출하는 전형적인 경기육괴의 편마암류로서 화강암질 정편마암이다. 이들 시료로부터 분리된 저어콘 입자들은 대부분 화성기원의 누대구조와 자형의 결정형태를 보여준다. 과성장띠(overgrouth rims)는 1006-5 시료에서 흔하게, 그리고 1006-9 시료에서 매우 드물게 관찰된다. 음극선발광(cathodoluminescence) 영상의 해석을 통해 저어콘 결정의 성장사를 유추하였으며, 이를 바탕으로 이온현미분석 점(spot)을 정하였다. U-Pb-Th 자료는 퍼스(Perth) 저어콘 스탠다드 (CZ3, 564 Ma, $^{206}$Pb/$^{238}$U=0.0914)를 사용하였다. 아래에 기술하는 연대는 모두 $^{206}$Pb/$^{238}$U 연대에 해당된다. 두 개의 화강암질 편마암 시료로부터 구한 U-Pb 저어콘 연대는 각각 812 $\pm$ 14 Ma(1006-8)와 822 $\pm$ 17 Ma(1006-9)로 분석오차 내에서 서로 일치한다. 이 결과는 춘천 및 전곡 지역의 석류석 각섬암에서 보고된 Sm-Nd 전암연대(852 $\pm$ 24 Ma 및 824 $\pm$ 143 Ma; Lee and Cho, 1995; Ree et al., 1996)와 잘 부합한다. 따라서 후기 원생대 기간 중 화성활동이 한반도에서 광범위하게 일어났음을 시사한다. 한편, 1006-9 시료에서는 예외적으로 한 개의 저어콘 입자 주변부(rim)에서 매우 얇은 과성장띠가 관찰되었으며, 두 개의 점 분석으로부터 구한 U-Pb 저어콘 연대는 약 235 Ma이다. 이 띠는 또한 변성기원의 저어콘에서 흔히 관찰되는 작은 W (<0.05) 비를 보인다. 1006-5 시료는 위 두 시료로부터 수 km 떨어진 지점에서 채집하였으나, 저어콘 연대는 상이한 기록을 보여준다. 즉 매우 작은 Th/U (<0.01) 값을 갖는 저어콘의 주변부에서 223 $\pm$ 5 Ma의 연대가 잘 정의되며, 이는 1006-9 시료에서 관찰된 결과와 함께 트라이아스기의 고온변성작용이 백립암상에 가까운, 매우 높은 온도에 달하였음을 지시한다. 한편 저어콘의 중심부는 335-473 Ma의 비교적 넓은 연대 분포를 보인다. 이는 저어콘이 실제 성장한 연대를 지시하기보다는 트라이아스기의 변성작용에 따른 납손실(Pb loss) 그리고 누대 규모보다 더 큰 빔 크기(beam size, 약 30 $\mu\textrm{m}$)의 영향일 것으로 해석된다. 또한 저어콘이 다양한 외래물질로부터 기원했다는 증거가 관찰되지 않으므로, 이 정편마암의 모암은 오르도비스기(약 430-470 Ma)에 관입하였을 것으로 생각된다. 따라서 그동안 논란이 되어 왔던 소위 “칼레도니아” 변동이 한반도 내에 실존하였을 가능성을 시사한다. 이상의 결과를 종합하여 볼 때, 경기육괴의 변성암류는 후기 원생대 이후 다양한 저어콘의 성장사를 기록하고 있음을 알 수 있다: 즉 (1) 후기원생대(약 820 Ma)의 화성작용; (2) 오르도비스기(약 450 Ma)의 화성작용: 그리고 (3) 트라이아스기 (약 223 Ma)의 부분용융을 수반한 고온 변성작용으로 대표된다. 이러한 지질연대는, 옥천변성대에서 얻어진 756 Ma의 저어콘 연대(Lee et al., 1998)와 더불어, 친링-다비-수루(Qinling-Dabie-Sulu) 대륙 충돌대와 양쯔 지괴에서 보고된 지질연대 결과와 잘 부합한다. 따라서 지구연대학적으로 경기육괴가 북중국보다는 대륙충돌대를 포함하는 남중국지괴에 속할 것으로 결론지을 수 있다.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.2
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• pp.65-71
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• 2011

Purpose: The recently adopted multiple confocal SPECT SYSTEM (hereinafter called IQ SPECT$^{TM}$) has a high difference from the conventional myocardial perfusion SPECT in the collimator form, image capture method, and image reconstruction method. This study was conducted to compare this novice equipment with the conventional one to design a protocol meeting the IQ SPECT, and also determine the characteristics and usefulness of IQ SPECT. Materials and Methods: 1. For the objects of LEHR (Low energy high resolution) collimator and Multiple confocal collimator, $^{99m}Tc$ 37MBq was put in the acrylic dish then each sensitivity ($cpm/{\mu}Ci$) was measured at the distance of 5 cm, 10 cm, 20 cm, 30 cm, and 40 cm respectively. 2. Based on the sensitivity measure results, IQ SPECT Protocol was designed according to the conventional general myocardial SPECT, then respectively 278 kBq/mL, 7.4 kBq/mL, and 48 kBq/mL of $^{99m}Tc$ were injected into the myocardial and soft tissues and liver site by using the anthropomorphic torso phantom then the myocardial perfusion SPECT was run. 3. For the comparison of FWHMs (Full Width at Half Maximum) resulted from the image reconstruction of LEHR collimator, the FWHMs (mm) were measured with only algorithms changed, in the case of the FBP (Filtered Back projection) method- a reconstruction method of conventional myocardial perfusion SPECT, and the 3D OSEM (Ordered subsets expectation maximization) method of IQ SPECT, by using $^{99m}Tc$ Line source. Results: 1. The values of IQ SPECT collimator sensitivity ($cpm/{\mu}Ci$) were 302, 382, 655, 816, 1178, and those of LEHR collimator were measured as 204, 204, 202, 201, 198, both at the distance of 5 cm, 10 cm, 20 cm, 30 cm, and 40 cm respectively. It was found the difference of sensitivity increases up to 4 times at the distance of 30 cm in the cases of IQ SPECT and LEHR. 2. The myocardial perfusion SPECT Protocol was designed according to the geometric characteristics of IQ SPECT based on the sensitivity results, then the phantom test for the aforesaid protocol was conducted. As a result, it was found the examination time can be reduced 1/4 compared to the past. 3. In the comparison of FWHMs according to the reconstructed algorithm in the FBP method and 3D OSEM method followed after the SEPCT test using a LEHR collimator, the result was obtained that FWHM rose around twice in the 3D OSEM method. Conclusion : The IQ SPECT uses the Multiple confocal collimator for the myocardial perfusion SPECT to enhance the sensitivity and also reduces examination time and contributes to improvement of visual screen quality through the myocardial-specific geometric image capture method and image reconstruction method. Due to such benefits, it is expected patients will receive more comfortable and more accurate examinations and it is considered a further study is required using additional clinical materials.

• The Korean Journal of Pesticide Science
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• v.18 no.2
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• pp.79-87
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• 2014

Pyriofenone is an aryl phenyl ketone fungicide that is newly registered in Korea in 2013 to control powdery mildew on food. The objective of this study was to develop reliable and sensitive analytical method for determination of pyriofenone residue in agricultural products for ensuring the food safety. The pyriofenone residues in all samples(Korean melon, pepper, potato, mandarin, soybean, and hulled rice) were extracted with acetonitrile, partitioned with dichloromethane, and then purified with a silica cartridge. The purified samples were analyzed by HPLC-UVD and confirmed with LC-MS. The linear range of pyriofenone was 0.05~5 mg/kg with the correlation coefficient ($r^2$) > 0.999. Average recoveries of pyriofenone ranged from 72.8% to 99.5% at the spiked level of 0.05 and 0.5 mg/kg, while the relative standard deviation was 2.3%~6.4%. In addition, the limit of detection and limit of quantification were 0.01 and 0.05 mg/kg, respectively. The results revealed that the developed and validated analytical method was suitable for pyriofenone determination in agricultural products.