• 치과방사선
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• 제28권2호
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• pp.435-459
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• 1998

In order to achieve a successful endodontic treatment, root canals must be obturated three-dimensionally without causing any damage to apical tissues. Accurate length determination of the root canal is critical in this case. For this reason, I've used the conventional periapical radiography, Digora/sup (R)/(digital imaging system) and Root ZX/sup (R)/(the frequency dependent type apex locator) to measure the length of the canal and compare it with the true length obtained by cutting the tooth in half and measuring the length between the occlusal surface and the apical foramen. From the information obtained by these measurements, I was able to evaluate the accuracy and clinical usefulness of each systems. whether the thickness of files used in endodontic therapy has any effect on the measuring systems was also evaluated in an effort to simplify the treatment planning phase of endodontic treatment. 29 canals of 29 sound premolars were measured with #15, #20, #25 files by 3 different dentists each using the periapical radiography. Digora/sup (R)/ and Root ZX/sup (R)/. The measurements were then compared with the true length. The results were as follows: 1. In comparing mean discrepancies between measurements obtained by using periapical radiography(mean error: -0.449±0.444 mm), Digora/sup (R)/(mean error: -0.417±0.415 mm) and Root ZX/sup (R)/(mean error: 0.123±0.458 mm) with true length. periapical radiography and Digora/sup (R)/ system had statistically significant differences(p<0.05) in most cases while Root ZX/sup (R)/ showed none(p>0.05). 2. By subtracting values obtained by using periapical radiography, Digora/sup (R)/ and Root ZX/sup (R)/ from the true length and making a distribution table of their absolute values. the following analysis was possible. In the case of periapical film. 140 out of 261<53.6％) were clinically acceptable satisfying the margin of error of less than 0.5 mm. 151 out of 261 (53,6％) were acceptable in the Digora/sup (R)/ system while Root ZX/sup (R)/ had 197 out of 261(75.5％) within the limits of 0.5mm margin of error. 3. In determining whether the thickness of files has any effect on measuring methoths, no statistically significant differences were found(p>0.05). 4. In comparing data obtained from these methods in order to evaluate the difference among measuring methods, there was no statistically significant difference between periapical radiography and Digora/sup (R)/ system(p>0.05), but there was statistically significant difference between Root ZX/sup (R)/ and periapical radiography(p<0.05). Also there was statistically significant difference between Root ZX/sup (R)/ and Digora/sup (R)/ system(p<0.05). In conclusion, Root ZX/sup (R)/ was more accurate when compared with the Digora/sup (R)/ system and periapical radiography and seems to be more effective clinically in determining root canal length. But Root ZX/sup (R)/ has its limits in determining root morphology and number of roots and its accuracy becomes questionable when apical foramen is open due to unknown reasons. Therefore the combined use of Root ZX/sup (R)/ and the periapical radiography are mandatory. Digora/sup (R)/ system seems to be more effective when periapical radiographs are needed in a short period of time because of its short processing time and less exposure.

• 대한치위생과학회지
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• 제3권1호
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• pp.1-13
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• 2020

The purpose of this study was to investigate the perception of calculus removal, an essential factor in periodontal disease in the elderly population. Further, the study aimed to identify the oral hygiene management matters of individuals and to use the information as primary data for preventing dental loss and improving the prevention of chronic diseases. From December 20, 2019, to January 15, 2020, the results of 171 studies on oral hygiene management and awareness of calculus removal among the elderly aged 65 or older in Busan and Gyeongnam are as follows: The elderly with good health appreciated their functional oral health status and showed significant differences (Χ²=298.26, p<.001). Many of the elderly brushing their teeth at least three times a day had a better health status and showed significant differences according to their health status (= 134.42, p <.001). Usually, older people who are in good health have a dental floss (Χ²=89.31, p<.001), and the dental floss were used more often and significantly differed depending o health status (Χ²=92.53, p<.001). The elderly's perception of tartar removal has shown that the overall average out of five points is positive at 3.48. Older female adults were more positive and showed significant differences regarding gender (t=-7.95, p<.001). Senior citizens aged 65 to 70 were more positive about dental removal than those aged 71 or older, with significant differences in age (t=6.65, p<.001). As described above, oral hygiene management for the elderly population needs to develop a periodontal disease prevention program linked to systemic diseases, considering that there are many chronic diseases.

• 한국수자원학회논문집
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• 제53권8호
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• pp.605-616
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• 2020

본 연구에서는 만경강유역(1,602 ㎢)을 대상으로 SWAT(Soil and Water Assessment Tool)을 이용하여 미래 극한 기후변화 시나리오와 유역간 물이동 감소에 따른 유역의 수문 수질 변화를 미래기간(S1: 2010~2039, S2: 2040~2069, S3: 2070~2099)로 구분하여 평가하였다. 이를 위해 유역간 물이동량, 유역내 취수량, 점 오염원 등을 고려하여 SWAT 모형을 구축 후 수위 관측소 2지점(대천, 전주), 수질 관측소 2지점(삼례, 김제)에 대하여 유출량과 부하량을 보정(2012~2014년) 및 검증(2016~2018년)하였다. 검보정 결과 유출량의 평균 R²는 0.7, NSE는 0.51이었으며, SS, T-N, T-P의 평균 R²는 0.72, 0.80, 0.72로 분석되었다. 미래 기후변화에 따른 연평균 유출량은 최대 459 mm/yr 증가하였으며, 연평균 SS, T-N, T-P 부하량은 각각 최대 19,548 ton/yr, 68,748 kg/yr, 13,728 kg/yr 증가하였다. 미래 유역간 물 이동량이 감소하였을 때, 봄과 겨울에 유출량이 감소하였으며, 미래 수질 부하량은 강수량의 영향으로 과거 관측 기간보다 증가하였다. 유출량 감소와 부하량 증가로 인한 수질 악화를 개선하기 위해서는 유역간 물이동이 일정 수준으로 지속되어야 할 것으로 판단된다.

• Clinical and Experimental Vaccine Research
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• 제12권1호
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• pp.47-59
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• 2023

Purpose: The development and study of hepatitis C virus (HCV) vaccine candidates' individualized responses are of great importance. Here we report on an HCV DNA vaccine candidate based on selected envelope (E1/E2) epitopes. Besides, we assessed its expression and processing in human peripheral blood mononuclear cells (PBMCs) and in vivo cellular response in mice. Materials and Methods: HCV E1/E2 DNA construct (EC) was designed. The antigen expression of EC was assayed in PBMCs of five HCV-uninfected donors via a real-time quantitative polymerase chain reaction. Serum samples from 20 HCV antibody-positive patients were used to detect each individual PBMCs expressed antigens via enzyme-linked immunosorbent assay. Two groups, five Swiss albino mice each, were immunized with the EC or a control construct. The absolute count of lymph nodes' CD4⁺ and CD8⁺ T-lymphocytes was assessed. Results: Donors' PBMCs showed different levels of EC expression, ranging between 0.83-2.61-fold in four donors, while donor-3 showed 34.53-fold expression. The antigens expressed in PBMCs were significantly reactive to the 20 HCV antibody repertoire (all p=0.0001). All showed comparable reactivity except for donor-3 showing the lowest reactivity level. The absolute count % of the CD4⁺ T-cell significantly increased in four of the five EC-immunized mice compared to the control group (p=0.03). No significant difference in CD8⁺ T-cells % was observed (p=0.89). Conclusion: The inter-individual variation in antigen expression and processing dominance was evident, showing independence in individuals' antigen expression and reactivity levels to antibodies. The described vaccine candidate might result in a promising natural immune response with a possibility of CD4⁺ T-cell early priming.

• 한국식품과학회지
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• 제53권5호
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• pp.619-627
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• 2021

본 연구는 코코아빈 가공과정에서 발생되는 부산물(by-product)인 코코아빈 허스크의 기능성식품소재로써 가능성과, 소시지의 냉장보관 중 저장성에 미치는 영향을 살펴보고자 하였다. 코코아빈 허스크 분말 추출물의 항산화활성을 알아보고, 코코아빈 허스크 분말을 첨가한 소시지(0, 0.25, 0.5, 1, 1.5, 2%, ascorbic acid 0.2%)를 제조하여 15일간(0, 5, 10, 15 일) 품질특성 변화를 살펴보았다. 카카오빈 허스크 분말 추출물의 총 폴리페놀과 총 플라보노이드 함량은 126.6 mg TAE/g와 80.19 mg QUE/g으로 측정되었으며, DPPH 라디칼 소거활성 IC₅₀은 44.28 ㎍/mL, ABTS⁺ 라디칼 소거활성 IC₅₀은 112.26 ㎍/mL으로 높은 항산화활성을 확인했다. 소시지의 총 폴리페놀 함량, 총 플라보노이드 함량, DPPH 및 ABTS⁺ 라디칼 소거활성은 코코아빈 허스크 첨가량에 따라 높아졌다(p<0.001). 저장 기간 동안 코코아빈 허스크 분말 첨가량이 증가할수록 pH 상승, redness 변색, 지질산화, 단백질변패, 조직감 변화 등과 같은 품질저하에 대한 억제효과를 나타냈다(p<0.05). 특히 1% 소시지는 ascorbic acid 소시지와 유사한 지방산패(TBARS) 및 단백질변패(VBN)를 억제하는 것으로 나타났다. 그러나, 생균수 측정에서는 실험군 간 유의적인 차이가 없었다. 관능적 특성에서는 향미기호도와 전반적인 기호도를 증가시켜 0.5%와 1% 첨가 소시지가 가장 높은 점수를 받았다. 결론적으로 코코아빈 허스크를 소시지에 1% 첨가할 경우 페놀화합물 함량, 항산화활성, 지질산화 및 단백질 변패 억제 효과를 향상시킴으로써 소시지의 가치를 높일 수 있으며, 코코아빈 허스크는 기능성식품 소재로써 이용 가능성이 높다고 생각된다.

• Molecules and Cells
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• 제43권10호
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• pp.889-897
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• 2020

K-RAS is frequently mutated in human lung adenocarcinomas (ADCs), and the p53 pathway plays a central role in cellular defense against oncogenic K-RAS mutation. However, in mouse lung cancer models, oncogenic K-Ras mutation alone can induce ADCs without p53 mutation, and loss of p53 does not have a significant impact on early K-Ras-induced lung tumorigenesis. These results raise the question of how K-Ras-activated cells evade oncogene surveillance mechanisms and develop into lung ADCs. RUNX3 plays a key role at the restriction (R)-point, which governs multiple tumor suppressor pathways including the p14^ARF-p53 pathway. In this study, we found that K-Ras activation in a very limited number of cells, alone or in combination with p53 inactivation, failed to induce any pathologic lesions for up to 1 year. By contrast, when Runx3 was inactivated and K-Ras was activated by the same targeting method, lung ADCs and other tumors were rapidly induced. In a urethane-induced mouse lung tumor model that recapitulates the features of K-RAS-driven human lung tumors, Runx3 was inactivated in both adenomas (ADs) and ADCs, whereas K-Ras was activated only in ADCs. Together, these results demonstrate that the R-point-associated oncogene surveillance mechanism is abrogated by Runx3 inactivation in AD cells and these cells cannot defend against K-Ras activation, resulting in the transition from AD to ADC. Therefore, K-Ras-activated lung epithelial cells do not evade oncogene surveillance mechanisms; instead, they are selected if they occur in AD cells in which Runx3 has been inactivated.

• 한국식품과학회지
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• 제54권1호
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• pp.8-16
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• 2022

히알루론산 첨가가 현미밥의 품질특성에 미치는 영향을 알아보기 위해 히알루론산의 농도를 달리한 용액(0-0.7%)을 취반수로하여 현미밥을 제조하고 그 특성을 평가하였다. 먼저 현미밥의 수분함량은 48.30-53.04%의 범위로 히알루론산 첨가량이 증가할수록 증가하였으며(p<0.05), pH는 6.73-6.74의 범위로 대조군과 시료군간에 유의적인 차이가 없었다(p>0.05). 색도의 경우, 명도는 히알루론산을 첨가할수록 유의적으로 낮아졌고(p<0.05), 적색도는 대조군과 시료군간 유의적인 차이를 나타내지 않았다(p>0.05). 그러나 황색도는 히알루론산 첨가량이 증가할수록 유의적으로 증가하였다(p<0.05). 현미밥의 유리라디칼 소거능은 대조군이 21.63%로 가장 낮았으며, 히알루론산의 첨가량이 증가함에 따라 유의적으로 증가하여 HA_0.7에서는 59.59%로 가장 높았으며(p<0.05), 총 폴리페놀 함량은 히알루론산 첨가량이 증가할수록 유의적으로 증가하여 HA_0.7에서 17.06 mg GAE/100 g으로 가장 높은 것으로 확인되었다(p<0.05). 현미밥의 경도는 히알루론산 첨가량이 증가함에 따라 대조군에서는 287,149 N/m²로 가장 높았으며, HA_0.7에서는 164,359 N/m²로 유의적으로 감소하였다(p<0.05). 점착성, 씹힘성 및 응집성은 히알루론산 첨가량이 증가할수록 유의적으로 감소하였고(p<0.05), 탄력성은 첨가량에 따른 유의적인 차이는 없었다(p>0.05). 저장 시 경도 변화는 히알루론산을 첨가량이 많아질수록 유의적으로 감소하였으며 HA_0.5와 HA_0.7은 저장 기간 별로 경도의 증가 폭이 대조군에 비하여 작았다(p<0.05). 기호도 검사 결과 외관, 향, 맛, 식감, 전반적인 기호도에서 대조군과 시료군 간에 유의적인 차이를 보이지 않았으며(p>0.05), 경도에서는 히알루론산 첨가군이 대조군보다 높은 선호도를 보이며 유의적인 차이를 나타냈다(p<0.05). 이상의 결과로 히알루론산의 첨가가 현미밥의 항산화 특성을 향상시키며, 물성을 개선함과 동시에 노화 시간을 늦추는 것을 확인할 수 있었으며, 고령자의 기호도를 높이며 부드러운 질감을 얻기 위해 첨가수준은 HA_0.7까지 적용 가능할 것으로 보인다.

• 문화기술의 융합
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• 제8권4호
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• pp.205-212
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• 2022

본 연구는 인문사회계열 대학생을 대상으로 자기효능감, 대인관계능력, 지각된 스트레스가 회복탄력성에 미치는 영향을 확인하기 위해 시도되었다. 연구참여자는 B시의 인문사회계열 전문대학생 330명을 대상으로 하였다. 자료 분석은 SPSS 22.0 프로그램을 이용하여 실수, 백분율, 평균, 표준편차, t-test, ANOVA, 피어슨 상관계수, 다중회귀분석으로 분석하였다. 대상자의 회복탄력성 평균 3.34±0.45점이었다. 대상자의 회복탄력성은 자기효능감(r=.521, p<.001), 대인관계능력(r=.678, p<.001)과 정적상관관계를 나타냈고, 지각된 스트레스(r=-.234, p<.001)와 부적상관관계를 나타냈다. 대상자의 회복탄력성에 영향을 미치는 요인은 자기효능감(β=.280, p<.001), 대인관계능력(β=.394, p<.001), 지각된 스트레스(β=-.191, p<.001)로 나타났고, 설명력은 53.3%로 나타났다. 본 연구결과를 통하여 인문사회계열 대학생의 회복탄력성에 영향을 미치는 요인을 확인할 수 있었다.

• Journal of Yeungnam Medical Science
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• 제37권2호
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• pp.90-97
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• 2020

Background: To minimize damage to the ovarian reserve, it is necessary to evaluate the follicular density in the ovarian tissue surrounding endometriosis on preoperative imaging. The purpose of the present study was to evaluate the usefulness of subtraction pelvic magnetic resonance imaging (MRI) to detect ovarian reserve. Methods: A subtracted T1-weighted image (^subT1WI) was obtained by subtracting unenhanced T1WI from contrast-enhanced T1WI (^ceT1WI) with similar parameters in 22 patients with ovarian endometriosis. The signal-to-noise ratio (SNR) in ovarian endometriosis, which was classified into the high signal intensity and iso-to-low signal intensity groups on the T2-weighted image, was compared to that in normal ovarian tissue. To evaluate the effect of contrast enhancement, a standardization map was obtained by dividing ^subT1WI by ^ceT1WI. Results: On visual assessment of 22 patients with ovarian endometriosis, 16 patients showed a high signal intensity, and 6 patients showed an iso-to-low signal intensity on T1WI. Although SNR in endometriosis with a high signal intensity was higher than that with an iso-to-low signal intensity, there was no difference in SNR after the subtraction (13.72±77.55 vs. 63.03±43.90, p=0.126). The area of the affected ovary was smaller than that of the normal ovary (121.10±22.48 vs. 380.51±75.87 ㎟, p=0.002), but the mean number of pixels in the viable remaining tissue of the affected ovary was similar to that of the normal ovary (0.53±0.09 vs. 0.47±0.09, p=0.682). Conclusion: The subtraction technique used with pelvic MRI could reveal the extent of endometrial invasion of the normal ovarian tissue and viable remnant ovarian tissue.

• Nuclear Engineering and Technology
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• 제53권11호
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• pp.3784-3789
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• 2021

We report a simple technique for direct neutron spectroscopy using pure LaCl₃ crystals. Pure LaCl₃ crystals exhibit considerably better pulse shape discrimination (PSD) capabilities with relatively good energy resolution as compared with Ce-doped LaCl₃ crystals. Single crystals of pure and Ce-doped LaCl₃ were grown using an inhouse-developed Bridgman furnace. PSD capabilities of these crystals were investigated using ²⁴¹Am and ¹³⁷Cs sources. Fast neutron detection was tested using a²⁵²Cf source and three separate bands corresponding to electron, proton, and alpha were observed. The proton band induced by the ³⁵Cl(n,p)³⁵S reaction can be used for direct neutron spectroscopy because proton energy is proportional to incident neutron energy. Owing to good scintillation performance and excellent PSD capabilities, pure LaCl₃ is a promising candidate for space detectors and other applications that necessitate gamma/fast neutron discrimination capability.