• 한국환경보건학회지
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• 제33권2호
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• pp.123-131
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• 2007

Many environmental contaminants including several metals, polycyclic aromatic hydrocarbons, and pharmaceuticals, have been identified to be phototoxic in the water environment. Concerns regarding photo-enhancement of toxicity of several environmental contaminants have been increasing because of the increased level of ultraviolet irradiation on the earth surface. However, there exist arguments that there might be certain defense mechanisms taking place in the aquatic ecosystem, which may include behavioral characteristics or genetic acclimation. This study was conducted to understand the potential responses of aquatic receptors to several phototoxic metals in the real environment, where long-term acclimation of such organisms to low dose UV-B may take place. For this purpose, water flea Daphnia magna was acclimated to environmentally relevant dose of UV-B (12 to $18uW/cm^2$) for >11 generations. The differences in developmental and life history characteristics, and toxicity responses were evaluated. Acclimation did not affect the daphnids' growth, longevity, and reproduction characteristics such as time to first brood, and brood size: After 21 d, survival of D. magna was not influenced by UV-B acclimation. When the number of young per female was compared. the daphnids acclimated for 11 generations tend to produce less number of neonates than the un-acclimated individuals but with no statistical significance (p>0.05). Four metals that were reported to be phototoxic elsewhere were employed in this evaluation, that include As, Cd. Cu, and Ni. UV-B level being applied in acclimation did increase the toxicity of Cd and Cu, significantly (p<0.05). However, the toxicities of As and Ni were not affected by irradiation of UV-B. Phototoxic responses were evaluated between the acclimated and the un-acclimated daphnids. For Cu, UV-B acclimation led to reduction of the photo-induced toxicity $(p\approx0.1)$ in daphnids. Non-acclimated Daphnia were affected by 50% at 4.18 ug/l Cu. but UV-B acclimated individuals exhibited $EC_{50}$ of 5.89 ug/l. With Cd, UV-B acclimation appeared to increase phototoxicity (p>0.05). With As and Ni, UV-B acclimation did not influence photo-induced toxicity. This observation may be in part explained by the type of reactive oxygen species that were generated by each metal. Similar to UV-B light, Cu is known to generate superoxide anion by acting as redox cycling toxicant. This is one of the first studies that employed_laboratory based UV-B acclimated test species for photoenhanced toxicity evaluation.

• The Journal of Advanced Prosthodontics
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• 제9권3호
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• pp.176-181
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• 2017

PURPOSE. The purpose of this study was to evaluate the marginal and internal gaps of Ni-Cr and Co-Cr copings, fabricated using the dental ${\mu}-SLA$ system. MATERIALS AND METHODS. Ten study dies were made using a two-step silicone impression with a dental stone (type IV) from the master die of a tooth. Ni-Cr (NC group) and Co-Cr (CC group) alloy copings were designed using a dental scanner, CAD software, resin coping, and casting process. In addition, 10 Ni-Cr alloy copings were manufactured using the lost-wax technique (LW group). The marginal and internal gaps in the 3 groups were measured using a digital microscope ($160{\times}$) with the silicone replica technique, and the obtained data were analyzed using the non-parametric Kruskal-Wallis H test. Post-hoc comparisons were performed using Bonferroni-corrected Mann-Whitney U tests (${\alpha}=.05$). RESULTS. The mean (${\pm}$ standard deviation) values of the marginal, chamfer, axial wall, and occlusal gaps in the 3 groups were as follows: $81.5{\pm}73.8$, $98.1{\pm}76.1$, $87.1{\pm}44.8$, and $146.8{\pm}78.7{\mu}m$ in the LW group; $76.8{\pm}48.0$, $141.7{\pm}57.1$, $80.7{\pm}47.5$, and $194.69{\pm}63.8{\mu}m$ in the NC group; and $124.2{\pm}52.0$, $199.5{\pm}71.0$, $67.1{\pm}37.6$, and $244.5{\pm}58.9{\mu}m$ in the CC group. CONCLUSION. The marginal gap in the LW and NC groups were clinically acceptable. Further improvement is needed for CC group to be used clinical practice.

• 대한교통학회지
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• 제22권2호
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• pp.131-143
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• 2004

최적경로 알고리즘에서 링크표지를 활용하면 도시가로망 상에 나타나는 유턴이나 피턴과 같은 주행했던 교차로를 다시 주행하는 통행에 대한 설명이 가능하다. 본 연구에서는 링크표지기법을 표지갱신기반 다수경로탐색알고리즘으로 확대하는 것이 목적이다. 이를 위해 도시가로망에서 발생하는 운전자의 합리적 통행행태를 링크기반으로 개념화하고, 이들 행태가 반영되도록 링크표지갱신 다경로 알고리즘을 제안하였다. 소규모 네트워크 테스트를 통하여 알고리즘의 수행과정과 결과의 적정성을 확인하였다. 대규모 네트워크 컴퓨터 수행을 통해 해의 퇴화현상을 파악하고 소수의 대안경로 정보제공에 활용 가능한 (K-1)차원 알고리즘을 제안하였다. 결론적으로 제안된 다수경로 알고리즘으로 링크표지기법이 제공하는 합리적 통행행태의 고려가 다수의 경로에도 가능해졌을 뿐만 아니라, 효율적인 대안경로 제공의 활용단계를 위해 한단계 전진되었다.

• 말소리와 음성과학
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• 제5권2호
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• pp.3-10
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• 2013

The purpose of this study is to analyze the acoustic characteristics of Korean alveolar sibilant sounds of children with cerebral palsy by acoustic analysis. Thirteen children with spastic cerebral palsy aging from 6 to 10 years old, were selected by an articulation test, and compared with a control group of thirty children. The meaningless monosyllable CV, disyllable VCV(/asa/) and frame sentence including target syllables CV were measured. C was from the /s, s'/, and V was from the set /a, i, u, ${\varepsilon}$, o, ɯ, ʌ/. Multi-Speech was used for data recording and analysis. As a result, the frication duration of lenis-glottalized alveolar sibilant of children with cerebral palsy was significantly shorter than that of the control group in CV, VCV and frame sentence. The vowel duration in the following lenis-glottalized alveolar sibilant of children with cerebral palsy was significantly longer than that of the control group in CV, VCV and frame sentence. The children with cerebral palsy showed frequency and intensity of friction intervals which were significantly lower than in the control group in CV, VCV and frame sentence. In the comparison of the lenis-glottalized alveolar sibilant by the children with cerebral palsy group's phonation types, the frication duration showed a significant difference between the phonation types in CV, VCV and between the phonetic contexts. The glottalized-sibilant was longer than the lenis-sibilant in all the phonetic contexts. The subsequent vowel duration showed a significant difference between the phonation types in VCV and between the phonetic contexts(p<.05). The vowel duration in the following glottalized-sibilant was longer than the vowel duration in the following lenis-sibilant in all the phonetic contexts. In the frequency there was a significant difference between the phonation types in CV, and in the intensity there was a significant difference between the phonation type in CV and VCV. The children with spastic cerebral palsy had difficulty in articulating the alveolar sibilant due to poor control ability in laryngeal, respiration and articulatory movements which require fine motor coordination. This study quantitatively analyzes the acoustic parameters of the alveolar sibilant in various phonetic contexts. Therefore, the results are expected to help provide fundamental data for an intervention of articulation treatment for children with cerebral palsy.

• 한국산학기술학회논문지
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• 제21권4호
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• pp.226-235
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• 2020

연구목적은 당뇨성 안질환 및 신장질환 합병증 검사 수검여부에 영향을 주는 요인을 알아보기 위함이다. 본 연구는 2017년 지역사회 건강조사 전국 자료를 이용하였으며, 연구대상은 의사에게 당뇨병을 진단받은 적이 있다고 응답한 사람 25,829명이다. 당뇨병 환자의 당뇨성 안질환 및 신장질환 합병증 검사 수검여부에 영향을 주는 요인을 알아보기 위해 로지스틱 회귀분석을 실시하였다. 연구결과는 당뇨병 환자 중 당뇨성 안질환 합병증 검사 수검율은 35.6%, 당뇨성 신장질환 합병증 검사 수검률은 39.8%이었다. 걷기실천을 할수록(OR=1.03, OR=1.02), 당화혈색소(OR=2.33, OR=2.33) 및 혈당수치(OR=1.61, OR=1.71)를 인지하는 사람과 현재 당뇨병 치료(OR=2.67, OR=3.05) 및 당뇨병 관리교육(OR=1.45, OR=1.47)을 받는 사람의 당뇨성 안질환 및 신장질환 합병증 검사를 받을 가능성이 많았다. 결론적으로 당뇨성 합병증 검사 수검율을 높이기 위해서는 당뇨병 환자를 대상으로 당뇨성 합병증 검사의 종류와 검사 시기가 포함된 당뇨병 관리 교육체계와 당화혈색소 및 혈당수치를 인지시킬 수 있는 다양한 홍보 방법 등이 개발되어야 할 것으로 생각된다. 그리고 당뇨병 관리를 위한 가이드라인 개발하고, 국가차원에서 국가검진제도에 당뇨성 합병증 검사 선별검사항목을 포함하는 등 시스템이 필요할 것으로 보인다.

• 대한한방내과학회지
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• 제31권2호
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• pp.314-330
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• 2010

Objective : This study was performed to investigate the anti-fibrogenic effect and changes of inflammation-related genes by YBR I and YBR II (YBR I: Arteisiae Capillaris Herba, Atractylodis Rhizoma Alba, Hoelen/ YBR II: YBR I +Sanguisorbae Radix, Biotae Cacumen, Cirsii Japonici Herba) on HSC(hepatic stellate cells)-T6 and TAA-induced rat liver tissue. Materials and Methods : HSC-T6 were treated with various concentrations of distilled-water extract YBR I and YBR II extract for 24, 48 and 72 hours. After the treatment, cell viability, proliferation, procollagen levels and IL-6 levels were measured by using MTT Assay, BrdU Assay, Procollagen Type 1 C-peptide EIA kit, and Murine IL-6 ELISA Development kit. Rat liver fibrosis was induced by intraperitoneal TAA injection of 150mg/kg 3 times a week for 6 weeks. After the treatment, body weight, liver & spleen weights, liver function test, complete blood cell count and change of portal pressure were studied. In addition, gene expressions of ASMA, IL-6, MMP-2, TIMP-1 and TIMP-2, all of which are known to be associated with liver fibrosis, were analyzed by using Real-Time PCR. After YBR I and YBR IItreatment, percentages of collagen in TAA-induced rat liver tissue were measured. Results : The viability and proliferation of the HSC-T6 decreased as the concentration increased. The production of procollagen decreased as the concentration increased. The production of IL-6 was little influenced by YBR I and YBR II. There was no difference in rat body weight between the TAA-only group and the YBR groups. Compared with rat liver weight of TAA-only group, that of the YBR groups increased. In the YBR I group, the serum level of AST elevated by TAA injection significantly decreased and in the YBR I and II group, the serum level of ALP and ALT elevated by TAA injection decreased. In the YBR I group, white blood cell count elevated by TAA injection decreased but platelets increased. In the YBR I group, the portal pressure elevated by TAA injection significantly decreased. Decreases in the gene expression of ASMA and MMP-2 were observed in the YBR I group. The gene expression of IL-6 was little influenced by YBR I and YBR II -treated groups. In the histological finding, TAA injections caused severe fibrosis, but YBR I and YBR II treatment significantly reduced the amounts of hepatic collagens. Conclusions : These results suggest that YBR I and II have inhibitory effects on the hepatic fibrogenesis.

• 한국축산식품학회지
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• 제31권1호
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• pp.47-53
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• 2011

Salmonella enterica serovar Typhimurium (ST) is one of the most common serovars isolated from humans and animals. It has been suggested that ST infections in Koreans are largely due to the consumption of contaminated pork and beef. To investigate the genotypes, phage types, and antimicrobial resistance patterns for ST isolates of different origins, a total of 70 ST strains, including 19 isolates from humans, 44 isolates from pigs, and 6 isolates from cattle, were analyzed using pulsedfield gel electrophoresis (PFGE), phage typing, and antimicrobial susceptibility tests. Forty-three distinct PFGE patterns were generated from 70 ST isolates, which were grouped into 14 PFGE groups (from A to N) at the level of 75% similarity. The most prevalent group was the A (A1-A17 subtypes) group, encompassing 54.5% (38/70) of ST isolates. ST isolates from pigs and cattle mostly belong to groups A and L, whereas ST isolates from humans mostly belong to groups F and C. Antimicrobial susceptibility tests using 11 antimicrobial agents showed that resistance to tetracycline (TE) (81.4%) was highly prevalent, followed by streptomycin (S) (64.3%) and nalidixic acid (NA) (31.4%) resistance. A total of seventeen antimicrobial resistance patterns were observed. Only 8.6% of isolates, including a reference strain, were susceptible to all antimicrobial agents tested. The most prevalent resistance pattern was TE-S (37.1%), which was seen in 66.6% of bovine, 40.8% of swine and 21.1% of human isolates. Three ST isolates from humans (15.9%) showed resistance to 7-8 antimicrobials. The most predominant phage type (PT) was U302 (64.3%), followed by DT170 (10.0%). PFGE types did not coincide with antimicrobial resistance patterns and phage types; therefore, the combination of those types allowed for further differentiation between tested ST isolates.

• Journal of Animal Science and Technology
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• 제45권5호
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• pp.841-846
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• 2003

Halothane 검정에 의한 L(Landrace) 및 Lw (Largewhite)의 halothane 양성돈 출현율은 각각 5.8, 6.6 %로 두 품종간에 큰 차이가 없었으며 음성과 양성돈의 중간반응을 나타내는 의양성돈은 20.5 %의 출현율을 보인 L과 Lw의 13.2 %에 비해 높았으나 음성돈 출현율은 L 및 Lw가 각각 76.1, 80.1 %로 Lw가 약간 높았다. hal-gene 분석결과는 L품종만이 hetro형이 출현하였을 뿐 전 조사 품종에서 halothane 양성돈은 나타나지 않았다. 품종별 pH1은 KNP (Korean Native Pig)가 L, Lw 및 H(Hybrid)에 비해 약간 높았으나 통계적 유의성은 없었다. pHu는 KNP와 H가 Lw 및 L에 비해 유의 (p〈0.05)하게 높았으나 KNP와 H품종사이에는 유의적인 차이가 없었다. NPPC 기준 육색은 L이 Lw 및 KNP에 비해 유의적(p〈0.05)으로 낮았고 H와는 유의차가 없었으며 CIE L*값 또한 같은 경향을 보여 L품종이 다른 품종보다 색깔이 창백한 고기를 생산할 기능성이 큰 것으로 사료되었다. 보수성은 재래종인 KNP가 H에 비해 유의적으로(p〈0.05)으로 높았으며 개량종인 Lw, L 및 H에서는 유의적인 차이가 없었다.

• 수산해양기술연구
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• 제20권1호
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• pp.37-42
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• 1984

응력집중부에 존재하는 균열에 대해서 J 평가식은 그 주위의 응력집중부의 국부변형과의 관계에 대해서 인장 및 압축이 있는 두곳에서 BEM 해석과 광탄성 실험한 결과와 COD 및 J치의 무차원량 J 하(E) /$\sigma$ 하(y) 상(2) a와 그 경우의 평균변형 및 항복변형의 비(e/e 하(y) )와의 관계는 균열의 길이에 의하지 않고 응력집중부의 형태에 거의 지배적으로 결정되는 일의적 대응관계가 있다. 2. 무한연속부 내부의 어떤 결함에 의한 평가식으로 부터 구한 값을 불연속 구조물내의 응력집중부에 존재하는 결함에 비하여 비교 정리하면, J 하(E) /$\sigma$ 하(y) 상(2) a=3.345(e/e 하(y) ) 상(2) 의 구간은 e/e 하(y) $\leq$1이고, J 하(E) /$\sigma$ 하(y) 상(2) a=3.345(e/e 하(y) )의 구간은 e/e 하(y) $\geq$1로서 이식들은 결함부 J평가식으로 사용할 수 있다. 3. 경계요소법에 의한 J식의 값과의 사이에는 가공경화율은 E/100을 사용하므로 이론과 실험결과가 거의 일치함을 보이고 상기 J식은 불연속평판 구조물이 결함을 가질 때 응력설계곡선의 자료가 될 수 있다.

• Archives of Plastic Surgery
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• 제36권6호
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• pp.691-701
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• 2009

Purpose: Deviations of arterial palmar arches in the hand can be explained on the embryological basis. The purpose of this study was to provide new information about palmar arches through cadaver's dissection. The values of the location and diameter in these vessels were analyzed in order to support anatomical research and clinical correlation in the hand. Methods: The present report is based on an analysis of dissections of fifty - three hands carried out in the laboratory of gross anatomy. A reference line was established on the distal wrist crease to serve as the X coordinate and a perpendicular line drawn through the midpoint between middle and ring fingers, which served as the Y coordinate. The coordinates of the x and y values were measured by a digimatic caliper, and statistically analyzed with Student's t - test. Results: Complete superficial palmar archs were seen in 96.2 % of specimens. In the most common type of males, the superficial arch was formed only by the ulnar artery. In the most common type of females, the superficial arch was formed anastomosis between the radial artery and the ulnar artery. The average length of the superficial and deep palmar arch is $110.3{\pm}33.0mm$ and $67.9{\pm}14.0mm$ respectively. Regarding the superficial palmar arch, ulnar artery starts $-16.1{\pm}5.1mm$ on X - line, and $2.5{\pm}24.5mm$ on Y - line. Radial artery appears on palmar side $7.7{\pm}3.2mm$ on X - line, and $20.9{\pm}10.9mm$ on Y - line. But radial artery starts on $6.3{\pm}3.6mm$ on X - line, and $3.4{\pm}5.1mm$ on Y - line. Digital arteries of superficial palmar arch starts on $6.1{\pm}3.7mm$, $33.9{\pm}8.8mm$ on index finger, $1.8{\pm}3.4mm$, $40.1{\pm}7.3mm$ on middle finger, $-3.2{\pm}4.9mm$, $42.6{\pm}7.0mm$ on ring finger, and $-8.9{\pm}5.1mm$, $42.5{\pm}80mm$ on little finger in respective X and Y coordinates. Radial artery of deep palmar arches measured at the palmar side perforating from the dorsum of hand. It's coordinates were $9.7{\pm}4.8mm$ on X - line, $21.7{\pm}10.2mm$ on Y - line. Ulnar artery was measured at hypothenar area, and it's coordinates were $-20.4{\pm}6.3mm$ on X - line, and $30.6{\pm}7.4mm$ on Y - line. Conclusions: Anatomically superficial palmar arch can be divided into a complete and an incomplete type. Each of them can be subdivided into 4 types. The deep palmar arch is less variable than the superficial palmar arch. We believe these values of the study will be used for the vascular surgery of the hand using the endoscope and robot in the future.