High-fructose corn syrup (HFCS) is widely used as sweetener, and its overconsumption is become a major health problem. In the present study, we used adult female rats and applied a 28 days HFCS feeding model to monitor the estrous cycle and changes in tissue weights and histology. Adult female rats were divided into three groups. Animals were fed with ad libitum normal chow and (1) 24 hours tap water (Control group), (2) 12 hours HFCS access during dark period and 12 hours tap water (12H group), and (3) 24 hours HFCS only access (24H group). Total exposure period was 28 days. There is no significant change in body weight between control and HFCS-fed animals. Both absolute and relative weights of ovary in 24H animals were significantly heavier than those in control or 12H animals. The absolute and relative weights of the kidney and liver in 24H groups were significantly heavier than those in control or 12H animals. The estrous cycles of the 24H animals were significantly longer. Histological analyses revealed that 24H ovaries were relatively bigger and possessed more corpus lutea than control ovaries. Uterine sections of 12H and 24H animals showed a well-developed stratum vasculare between inner and outer myometrial layers. The number of endometrial glands were decreased in 12H uteri, and recovered in 24H uteri compared to control. Numbers of convoluted tubule in distal region increased in 12H and 24H kidney samples. Liver specimens of 12H and 24H showed the increased number of fat containing vacuoles. In conclusion, our study demonstrated that HFCS treatment for 28 days could induce (1) changes in length of estrous cycle with extended estrous and diestrous stages, (2) altered ovarian and uterine histology, and (3) liver and renal lipid accumulation. These findings reveal the adverse effects of HFCS drinking on the reproductive function and lipid metabolism of female rats.

Metformin is the most commonly prescribed anti-diabetic drug with relatively minor side effect. Substantial evidence has suggested that metformin is associated with decreased cancer risk and anticancer activity against diverse cancer cells. The tyrosine kinase inhibitor imatinib has shown powerful activity for treatment of chronic myeloid leukemia and also induces growth arrest and apoptosis in colorectal cancer cells. In this study, we tested the combination of imatinib and metformin against HCT15 colorectal cancer cells for effects on cell viability, cell cycle and autophagy. Our data show that metformin synergistically enhances the imatinib cytotoxicity in HCT15 cells as indicated by combination and drug reduction indices. We also demonstrate that the combination causes synergistic down-regulation of pERK, cell cycle arrest in S and G2/M phases via reduction of cyclin B1 level. Moreover, the combination resulted in autophagy induction as revealed by increased acidic vesicular organelles and cleaved form of LC3-II. Inhibition of autophagic process by chloroquine led to decreased cell viability, suggesting that induction of autophagy seems to play a cell protective role that may act against anticancer effects. In conclusion, our present data suggest that metformin in combination with imatinib might be a promising therapeutic option in colorectal cancer.

Compton suppression apparatus using the Compton scattering response, by inhibiting part of the spectrum Compton continuum Compton continuum in the area of the peak analysis of the gamma rays that enables a clearer device. In order to find out the geometry structure of high-purity germanium detector(HPGe) -NaI(TI) and to optimize the effect of movement, Monte Carlo simulation was used to grasp the behavioral characteristics of Compton suppression and compare several layout structures. And applied to the cylinder beaker used for the environmental measurement by using the efficiency according to the distance. For the low-energy source such as 81 keV, the Compton continuum is scarcely developed and the suppression effect is also insignificant because the scattering cross-section of the Compton effect is relatively low. In the spectrum for the remaining energy, it can be seen that the Compton continuum part is suppressed in a certain energy range. Compton suppression effect was not significantly different from positional shift. average reduction factor(ARF) value was about 1.08 for 81 keV and about 1.23 for 1332.4keV energy at the highest value .It can be seen that suppression over the Compton continuum region of the energy spectrum is a more appropriate arrangement. Therefore, it can be applied to various environmental sample measurement through optimized structure.

The purpose of this study was to evaluate the clinical efficacy of 128 MDCT (multi-detector computed tomography) for reducing the CareDose 4D dose and comparing the image quality with the fixed tube current technique. For this purpose, we conducted the phantom and clinical studies to evaluate the exposure dose and image of the subject before and after applying the CareDose 4D system in abdominal examination using 128 MDCT. In the phantom study, ROI (Region of interest) was located at the center, 3, 6, 9, 12 o'clock, into two groups: group A without CareDose 4D and Group B applied were measured. In the clinical study, ROI was located at the liver 8 segments, divided into two groups too. The measured items were CT number, noise, and dose length product (DLP) dose. The result of CTDIvol (CT Dose Index volume) measurements in phantom and clinical studies were lower than those before CareDose 4D application, and dose and effective dose were also measured lower (p<.05). There was no difference in CT number before and after application (p>.05). In conclusion, using CareDose 4D, we can obtain optimal image information without deteriorating image quality while reducing patient dose.

Purpose – The purpose of this paper was to analyze the Chinese government’s announcement of the RMB’s appreciation on July 1, 2010, and its aim was to ascertain whether the appreciation has affected Chinese export prices by empirically measuring the degree of the exchange rate pass-tough on those prices. Research design, data, and methodology - Using 73 HS trade categories with cross-industry and time-series data, the panel estimation of a fixed-effects model has been applied to measure the degree and stability of any exchange rate pass-through effects. The estimation results show that the export prices of most trade categories were affected by the exchange rate changes. The pass-through effect was generally small, at about –0.485, and statistically significant in most export prices. Results - The empirical results indicate that China would lose its advantage and competitiveness in export if the RMB were appreciated continuously and rapidly because its export goods would no longer operate under strong monopolistic competition. Conclusions – The implications for China’s exchange rate policy suggest that it would be better for the RMB to appreciate slowly and gradually rather than radically. It is clear that it would be allow the capital free flow in Chinese overall economic interest to reduce the continuous appreciation pressure on the currency and pave the way for improvements in export distribution competitiveness.

The aim of this work to investigate the distribution of mercury in the gas phase, bottom ash and fly ash during the combustion of coal and solid waste such as dried sludge and solid refuse fuel (SRF) because the solid waste can be used as alternative fuel. In our study, we used two types of continuous combustors including vertical and horizontal combustor at the same conditions. In vertical combustor, we can get only the bottom ash while in horizontal combustor we get both fly ash and bottom ash. For both combustors, the gaseous mercury was measured by using the Ontario Hydro Method. The results showed that a significant amount of emission of gas phase mercury occurs during the combustion of coal, dried sludge, and SRF. Among the fuels, SRF showed high mercury oxidation while dried sludge showed a high level of gaseous mercury emission in the flue gas.

경피적 추체 성형술은 최소 침습적 척추 수술로 골다공증성 압박골절, 골수종 그리고 암에 의한 척추 전 이 등에 치료방법으로 많이 사용되어 왔다. 이러한 최소침습적 시술은 환자에게 작은 수술 흉터, 통증, 출혈, 짧은 회복시간등 여러가지 장점이 많으나, 환자와 시술자가 방사선의 위험으로부터 벗어날 수 없다. 이에 본 연구의 목적은 경피적 추체 성형술을 하는 동안 방사선 조사시간의 측정과 함께 시술자와 환자의 방사선 피폭선량을 측정해 보았다. 본원에 내원한 경피적 추체 성형술 시행 대상인 환자를 3명의 마취통증의 학과 전문의가 동일한 방법으로 총 20명의 환자에게 경피적 추체 성형술을 실시하였다. 방사선 조사시간을 측정하고 전자선량측정계를 이용하여 총 6군데의 방사선 피폭량을 측정해 보았다. 환자는 직접 엑스선을 측정하였으며, 전 후면과 옆면 부위에 전자선량측정계를 위치하였고, 시술자는 환자로부터 산란되는 산란선을 측정하였으며, 납가운 바깥쪽에 위치한 갑상선, 왼쪽 가슴, 왼쪽 허벅지 그리고 납가운 안쪽에 위치한 왼쪽 가슴부위에 전자선량측정계를 위치하였다. 총 시술 시간은 19.3±3.88 min이며, 방사선에 의한 노출 시 간은 3.6±0.71 min 이었다. 환자의 피폭선량은 전후면 일 때 121.4±48.15 μSv 였으며, 측면일 때 피폭선량 은 614.7±177.14 μSv 이다. 시술자가 받은 피폭선량은 납가운 바깥쪽의 갑상선 부분이 33.7±7.30 μSv 이고, 왼쪽 가슴 부위가 49.2±15.09 μSv 이고, 왼쪽 허벅지 부위가 12.8±3.80 μSv 이며, 납가운의 안쪽 가슴에 위치한 부위의 선량계는 4.2±1.44 Sv 이였다. 경피적 추체 성형술 시행 시 방사선의 위험으로부터 벗어나기 위해 C-arm 튜브에서 환자에게 엑스선이 도달하여 산란되는 거리를 최대한 멀게 유지하여야 하며, 방사선이 조사되는 시간을 줄이고, 납가운등 보호장구를 적절히 착용하여 방사선 피폭을 줄임으로써 시술자와 환자 모두 안전한 시술이 되도록 노력하여야 할 것이다.

On the 15 days after hatching, the larvae was 4.24-5.10 mm (mean 4.66±2.18 mm) in total length, and the fins of the membrane started to develop into a fan shape and the melanophore was deposited upper the alimentary canal of the abdomen and on the bladder. At 35 days after hatching, the post-larvae formed a branch-shaped melanophore on the head part with a total length of 6.98-12.5 (mean 9.35±1.71) mm, formed on the upper and lower parts of the caudal part, formed on the upper and lower parts of the caudal part, and deposited under the head part and abdomen. At 40 days after hatching, the juvenile was 11.3-18.1 (mean 14.9±1.53) mm in total length.

소사나무(Carpinus turczaninowii, C. turczaninowii) 잎 추출물의 멜라닌 생성 억제활성을 B16F10 melanoma 세포를 이용하여 측정하였다. 그 결과, 에탄올 추출물(100 μ g/mL)에서 72.2%의 생성 억제 효과를 확인하였으며, 동일 농도에서 MTT 세포독성은 거의 나타나지 않았다. 분획물(헥산, 에틸아세테이트, 부탄올 및 물)을 제조한 후 실험을 진행한 결과, 에틸아세테이트 분획에서 가장 우수한 활성이 관찰되었다. 에틸아세테이 트 분획에서 활성성분을 규명하기 위하여 크로마토그라피를 진행하였으며, 4개의 화합물을 분리 동정하였다; ethyl gallate (1), quercetin rhamnose (2), kaempferol rhamnose (3), quercetin galloylrhamnose (4). 화합물의 구조규명은 핵자기공명분광기 등을 이용하여 이루어졌으며, 4개의 화합물 모두 소사나무 잎에서는 처 음 분리된 물질이다. 분리된 화합물을 대상으로 멜라닌 생성 억제활성 실험을 진행한 결과, 화합물 4에서 세포독 성 없이 농도의존적인 억제활성을 확인하였다. 또한, 화합물 4는 세포 내에서 티로시나제 발현양을 감소시키고 있음을 ELISA를 통하여 확인하였다. 이상의 결과를 바탕으로, 소사나무 잎 추출물이 화장품에서 미백제로 활용 될 가능성이 있다고 판단된다.

Tomatoes are considered as one of the main components of daily meals in most households. Thus, it is important to invest in studies enhancing their yield and nutritional value. The study evaluated the effect of wood vinegar (WV) on tomato under greenhouse conditions. Data on fruit number, fruit weight, and plant height were recorded. Total phenolic content (TPC) and antioxidant activity of tomato were determined using the Folin-Ciocalteu reagent and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, respectively. FRR-CF+500x-WV significantly increased the fruit number (86.11%) and fruit weight (81.78%) over the control. Results were comparable to HRR-CF+250x-WV, indicating that conventional fertilizer and WV may have synergistic effect on each other. TPC and scavenging effect on DPPH radical was improved by 250x-WV application. The increase in the phenolic compounds can be attributed to WV as a direct source or as a factor triggering the plants to produce more secondary metabolites with the purpose of increasing natural defenses. The significant effect obtained by applying the full recommended rate of conventional fertilizer on the carotenoid content was due to the availability of the major nutrients needed by the plant. Correlation analysis showed that carotenoids have negative correlation with TPC and DPPH. However, TPC and DPPH showed that these are positively correlated with each other. Tomatoes are excellent source of antioxidants associated with the reduction of some human diseases and improved health. The results provided evidence that WV alone and/or its combination with conventional fertilizers has favorable effects on the quality of tomato.

Various bioactive substances are found in mistletoe, including viscumneoside III (1) and homoflavoyadorinin B (2), both which inhibit tyrosinase. These two compounds are mainly found in the EtOAc fraction of the mistletoe extract and demonstrate higher rates of tyrosinase inhibition than ascorbic acid, which was used as a control. Our results suggest that mistletoe extracts can be utilized in skin whitening cosmetics.

Rice blast, caused by a fungus Magnaporthe oryzae, is one of the most devastating diseases of rice worldwide. Analyzing the valuable genetic resources is important in making progress towards blast resistance. Molecular screening of major rice blast resistance (R) genes was determined in 2,509 accessions of rice germplasm from different geographic regions of Asia and Europe using PCR based markers which showed linkage to twelve major blast R genes, Pik-p, Pi39, Pit, Pik-m, Pi-d(t)2, Pii, Pib, Pik, Pita, Pita/Pita-2, Pi5, and Piz-t. Out of 2,509 accessions, only two accessions had maximum nine blast resistance genes followed by eighteen accessions each with eight R genes. The polygenic combination of three genes was possessed by maximum number of accessions (824), while among others 48 accessions possessed seven genes, 119 accessions had six genes, 267 accessions had five genes, 487 accessions had four genes, 646 accessions had two genes, and 98 accessions had single R gene. The Pik-p gene appeared to be omnipresent and was detected in all germplasm. Furthermore, principal component analysis (PCA) indicated that Pita, Pita/Pita-2, Pi-d(t)2, Pib and Pit were the major genes responsible for resistance in the germplasm. The present investigation revealed that a set of 68 elite germplasm accessions would have a competitive edge over the current resistance donors being utilized in the breeding programs. Overall, these results might be useful to identify and incorporate the resistance genes from germplasm into elite cultivars through marker assisted selection in rice breeding.

본 연구는 통계적 속성에 기반한 질감특징값 분석을 바탕으로 뇌 전산화단층촬영 영상에서 정상과 뇌경색의 컴퓨터보조진단의 적용 가능성을 알아보고자 하였다. 실험은 질감특징값을 나타내는 6개의 파라미터를 이용한 질환인식률 평가와 ROC curve를 분석하였다. 그 결과 평균밝기 88%, 대조도 92%, 평탄도 94%, 균일도 88%, 엔트로피 84%의 높은 질환인식률을 나타내었다. 하지만 왜곡도의 경우 58%로 다소 낮은 질환 인식률을 나타내었다. ROC curve를 이용한 분석에서 각 파라미터의 곡선아래면적이 0.886(p=0.0001)이상을 나타내어 질환인식에 의미가 있는 결과로 나타났다. 또한 각 파라미터의 cut-off값 결정으로 컴퓨터보조진단을 통한 질환예측이 가능할 것으로 판단된다.

The present research was chiefly designed to determine the effect of the treatment of estrogenic agonist, estradiol benzoate (EB), or antiandrogenic compound, flutamide (Flu), at the weaning age on the expression of connexin (Cx) isoforms in the caudal epididymis of adult male rat. Animals were subcutaneously administrated with a single shot of either EB at a low-dose (0.015 mg of EB/kg body weight (BW)) or a high-dose (1.5 mg of EB/kg BW) or Flu at a low-dose (500 mg of EB/kg BW) or a high-dose (5 mg of EB/kg BW). Expressional changes of Cx isoforms in the adult caudal epididymis were examined by quantitative real-time PCR analysis. The treatment of a low-dose EB caused significant increases of Cx30.3, Cx31, Cx32, and Cx43 transcript levels but reduction of Cx31.1, Cx37, and Cx45 expression. Exposure to a high-dose EB resulted in very close responses observed in a low-dose EB treatment, except no significant expressional change of Cx37 and a significant induction of Cx40. Expression of all Cx isoforms, except Cx45, was significantly increased by a low-dose Flu treatment. Expressional increases of all Cx isoforms were detected by a high-dose Flu treatment. The current study demonstrates that a single exposure to estrogenic or antiandrogenic compound during the early postnatal developmental period is sufficient to disrupt normal expression of Cx isoforms in the adult caudal epididymis.

The purpose of this study was to investigate the improvement of growth in Israeli carp (Cyprinus carpio), and the cross experiment was carried out with two strains of Israeli carp. Four combinations of Israeli carp from Jeonbuk fisheries farm and Songpu mirror carp from Heilong Jiang, China (KK; Jeonbuk ♀ × Jeonbuk ♂, KC; Jeonbuk ♀ × China ♂, CC; China ♀ × China ♂ and CK; China ♀ × Jeonbuk ♂) were developed and reared. Body length, body weight and condition factor were determined at 20, 40, 60 and 170 days post-hatch (DPH). The results showed that there were differences in growth rate of the four groups. Body length of four groups were CK > CC > KC > KK and body weight were CC > CK > KC > KK at 170 DPH. The growth perfomance of four groups were statistically significant difference (P<0.05). During the rearing, CC group had longer length and higher weight at 170 DPH compared to other three groups and also condition factor was highest in the CC group, but there was no significant difference in a survival rate. These results indicated that the growth performance mainly depended upon brooder combination but survival rate could not significantly affect brooder.

1913년의 동경협정, 1922년의 요코하마협정, 1929년의 태평양문제연구 회를 관통하는 YMCA의 첨예한 관심사는 문화적 자치의 공간이었다. 이는 외교적 협력을 통해 획득한 한국YMCA의 고유한 권리로, 정치적 독립을 상실한 일제 강점기의 한국에 문화적 독립에 상응하는 권리를, 외교권이 박탈당한 한국에 국제교류의 통로를 제공하였다. 1913년 일본 동경에서 체 결한 동경협정은 한국 YMCA가 보유한 문화민족주의 실현의 자치권을 일 본YMCA의 체제에 예편시켜, 기관명칭, 의사집행부, 법규제정에 이르기까 지 일본 YMCA에게 동반적 통제권을 부여했다. 그러나 1922년 체결한 요 코하마협정은 동경협정조문의 실행에 제동을 걸고, 기관명칭, 건물소유권, 의사집행부구성, 선교사 관할영역에 이르기까지 한국 YMCA의 독자적 자 치권을 천명하고, 구체적으로 반영할 제도적 장치를 마련하였다. 이러한 한일YMCA의 쌍방협약은 3년 후 미국, 캐나다, 오스트레일리아, 뉴질랜드, 중국, 일본, 필리핀, 하와이로 구성된 태평양문제연구회에 1925년부터 1929년에 이르기까지 한국 대표의 정체성을 가지고 일본과 구별된 독자적 국제교류를 가능하도록 수문을 개방했다. 1925년 태평양문제연구회라는 국제기관의 발족단계에서부터 시작된 한국의 참여는 한국문화를 말살시키는 일본정책을 보고를 가능하게 하였고 해외전문가의 호응을 이끌어 내었 다. 1907년 헤이그 만국평화회의나 1920년 파리강화회의에서 기회조차 두 절된 식민지 한국의 상황 및 한국인의 입장은 1925년 제 1회 태평양문제연 구회에서 평화적으로 진술되었고 1차 세계대전 후 평등과 상생이 지배하 는 국제적 신질서를 모색하는 태평양문제연구회의 이해를 증진하는데 기 여했다. 즉 한국YMCA는 단순히 민족주의의 보루일 뿐만 아니라 기독교 세계주의에 입각하여 민족주의의 이상을 구현할 자치의 공간을 제공하였 다. 한국 YMCA의 민족주의는 가시적이고 단기적인 투쟁을 통해서라기 보 다 장기적이고 은밀한 외교적 방식을 사용하였고 국제주의에 입각한 협력 을 통해 획득한 자치공간 안에서 발현되었다. 국제기구라는 장막 안에 숨 겨진 민족적 이상을 실현할 장이요 민족 지도자를 양육할 백년지대계를 이 행할 장이었다. 이러한 YMCA의 국제주의와 민족주의의 정신을 꿰뚫고 있는 중심인물 은 윤치호로서 그의 YMCA 훈련은 한국YMCA역사의 오류로 알려진 최초 의 YMCA가담자 여병헌에 선행한다. 윤치호는 여병헌이 런던으로 가는 1896년, 한국에 YMCA가 도입된 1903년 이전, 미국의 반더빌트 대학, 에 모리 대학, 학생자원운동의 학생 YMCA대표로 활동했고, 전국신학교 선교 연맹 및 조지아주 YMCA컨벤션에서 YMCA 지도자 훈련을 몸에 익혔던 YMCA인이었다. 윤치호는 뉴욕 본부가 지원한 한국인 최초의 YMCA간사 였고, 모트 등 해외 YMCA 간사의 한국인 자문이었으며, 일제 강점기 수 십 년 동안 YMCA 이사회 회장을 역임했다. 일제 강점기에 한국의 봉쇄 및 이권 착취의 최대걸림돌은 국제관계를 유지한 YMCA의 제압이었다. 따 라서 일제는 105인 사건으로 윤치호가 대구 구치소에 투옥된 기간, 이상재, 남궁억, 신흥우, 아비슨 및 언더우드의 참석과 존 모트의 진행가운데 동경 협정을 체결하여 자치권을 보유한 한국 YMCA에 일본의 감독권을 침투시켰다. 여기에 애국자로 묘사된 한국YMCA 인사들이 한국 YMCA를 일제 에 복속시키는 협정에 서명한 것이다. 그러나 1922년 YMCA의 요코하마 협정에서는 윤치호가 선제공격을 감행하여 한국 YMCA의 자치권을 탈취 하였고, 이로 인해 1925년 YMCA 중심의 태평양문제연구회의 활동이 가 능했으며, 1929년 일제가 태평양문제 연구회에 한국인 참여금지법안을 제 정하고자 상정할 때 한국태평양연구회 회장인 윤치호가 전면에서 한국인 참여의 정당성을 효과적으로 변호하였다. 이러한 역사적 국면은 일반적으 로 애국자의 표상으로 구축된 인물의 해석이나, 윤치호는 삼일운동 이후 사회진화론에 입각해 친일로 기울었고 대동아이론에 기초하여 서구를 배 척하고 친일에 전향했다는 양극단적 해석의 실증적 검토를 필요로 한다. 역사자료의 실증적 검토는 윤치호가 중일전쟁 이후 친일로 경도된 사실을 긍정함에도 불구하고, 식민지시대에 복잡하게 얽힌 억압의 현실이 친일파 내지 애국자라는 양극단적 해석의 틀에 개인생애 전반과 집단 전체를 삽입 하여 유형화하는 것을 용인하지 않았고, 그러기에는 선택의 폭이 다양하고 유동적이었음을 시사한다.

Purpose - The purpose of this study is to discover how Korean expatriates that are currently employed in Korean subsidiaries operational in Malaysia possibly suffer from career dissatisfaction due to differences between Korean Corporate Culture (KCC) and Malaysian Corporate Culture (MCC). The integration of KCC into MCC is discussed. Research design, data, and methodology – The analysis herein is via a qualitative research. Forty-six interviewees voluntarily participated in in-depth interviews. Document analysis and qualitative interviews were utilized to develop participant profiles and to generate the framework. Interview data were transcribed and subsequently analysed to facilitate the development of themes and ultimately led to emerging patterns. The framework discusses the following Confucian pillars pronounced in KCC: Control Systems, Power Structures, Organisational Structures, Authority and Harmony and Stories and Myths. Those pillars are analysed and the results of the interviews are discussed in detail. Results – Korean expatriates on assignment in Malaysia endure struggles in all five selected Confucian pillars as they are not symmetrical with Korean Corporate Culture common at head companies in Korea. Conclusion - As a consequence, there is substantial disharmony which needs to be rectified if Korean companies are to continue their ‘miraculous’ economic movement into the country.

Prior literature expects a lower marginal cash value for weaker governance firms. We test this empirical hypothesis by using the sample of publicly traded Korean firms from 2005 to 2013. To measure the quality of governance structures, we employ the corporate governance scores provided by Korean Corporate Governance Services. The empirical model of Faulkender and Wang (2006) is adopted to estimate the marginal value of cash. Our empirical analysis shows a higher marginal value of cash for the good governance firms in the examination of the total governance score. This finding is consistent to the agency view of cash policy predicting a larger marginal value of cash for the firms with higher governance scores. However, this positive relationship is not robust for a subset of detailed governance scores; a lower marginal cash value is observed for the firms with better qualities of board structure, auditing, dividend policies. Moreover, our empirical analysis verifies a quite low level of marginal cash value for Korean firms, which supports the existence of severe agency conflicts in Korean corporations. Our results verify the significant role of agency conflicts between a manager and shareholders in the determination of marginal cash values in the Korean firms.

본 연구는 복부 전산화단층촬영 영상을 이용하여 지방간환자의 영상을 질감특징분석과 ROC curve 분석을 하였으며, 컴퓨터보조진단시스템의 구현을 위한 실험적인 선형 연구로서 전산화단층촬영 영상에서 지방간의 객관적이고 신뢰성 있는 진단 정보를 의사에게 제공하고자 하였다. 실험은 정상 및 지방간 복부 전산화단층촬영 영상을 실험영상으로 하여 설정된 구역에 대한 wavelet 변환을 거쳐 질감의 특징값을 나타내는 6가지 파라미터로 통계적 분석 결과를 나타내었다. 그 결과 엔트로피, 평균밝기, 왜곡도는 90% 이상의 비교적 높은 인식률을 보였고, 대조도, 평탄도, 균일도는 약 70% 정도로 비교적 낮은 인식률을 나타내었다. ROC curve를 이용한 분석에서 6가지의 파라미터 모두 0.900(p=0.0001)이상을 나타내어 질환인식에 의미가 있는 결과를 나타내었다. 또한 6가지 파라미터에서 질환 예측을 위한 cut-off 값을 결정하였다. 이러한 결과는 향후 복부 전산화단층촬영 영상에서 질환 자동검출 및 최종진단의 예비 진단 자료로서 적용 가능할 것이다.

본 연구는 X-선관 각도 변경에 따른 경사효과(Anode Heel Effect)의 변화를 알아보고자 실시하였다. 실험조건은 70 kV, 30 mAs, 초점-검출기간의 거리 100 cm, 조사야는 35×43 ㎠, 측정점은 조사야의 정중앙점에서 좌우 3.5 cm 간격으로 나누어 양극쪽으로 A1, A2, A3, A4, A5, A6 점을 설정하고 음극쪽으로 C1, C2, C3, C4, C5, C6 점으로 설정하였다. X-선관을 수직으로 하여 측정점인 A6에서 C6까지 각각 입사표면선량을 측정하였다. 다음에 X-선관을 양극쪽으로 15도 30도로 변경 하면서 각각 측정하고 같은 방법으로 음극쪽으로 15도 30도로 변화시켜 측정하였다. 결과로 X-선관이 수직인 경우 A5보다 C5점이 3배정도 입사표면선량이 높게 나타나 수직 촬영 시 방사선감수성이 높은 장기가 위치해 있는 쪽으로 양극을 위치시키면 피폭을 줄일 수 있었다. X-선관의 각도를 주고 촬영할 경우에는 음극측으로 각도를 주는 것이 양극과 음극측의 입사표면선량 차이를 줄일 수 있으며 상, 하 두께 차이가 있는 부위를 촬영할 경우에는 음극측이 두꺼운 부위를 향하게 각도를 주는 것이 입사표면선량의 차이를 줄여 좀 더 균일한 영상을 만들 수 있었다.