• 한국미생물·생명공학회지
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• 제42권3호
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• pp.307-311
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• 2014

폴리우레탄 담체가 혼합폐기물을 이용한 연속식수소생산에 미치는 영향을 조사하였다. 당밀폐수와 하수슬러지를 혼합하여 연속 회분식 공정에서 발효시켰다. 담체를 넣지 않고 12 h의 수리학적 체류시간으로 운전하였을 때, 대부분의 바이오매스가 외부로 유실된 반면, 담체를 반응조에 투입하였을 때에는 미생물 유실이 현저히 저감하였다. 또한, 담체를 이용한 경우, 수소생산속도 $0.4L-H_2L^{-1}d^{-1}$로 높게 나타났다. 반응조 내 부유 바이오매스에 의한 비수소생산속도가 $241{\pm}4ml-H_2g-VSS^{-1}d^{-1}$로서 담체 표면 부착바이오매스($133{\pm}10ml-H_2g-VSS^{-1}d^{-1}$) 및 담체 내부 부착 바이오매스에 의한 값($95{\pm}14ml-H_2g-VSS^{-1}d^{-1}$)보다 높게 나타났다.

• Nutrition Research and Practice
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• 제6권2호
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• pp.155-161
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• 2012

Excessive oxidative stress and abnormal blood lipids may cause chronic diseases. This risk can be reduced by consuming an antioxidant- and fiber-rich vegetarian diet. We compared biomarkers of oxidative stress, antioxidant capacity, and lipid profiles of sex- and age-matched long-term vegetarians and omnivores in Korea. Forty-five vegetarians (23 men and 22 women; mean age, $49.5{\pm}5.3$ years), who had maintained a vegetarian diet for a minimum of 15 years, and 30 omnivores (15 men and 15 women; mean age, $48.9{\pm}3.6$ years) participated in this study. Their 1-day, 24-h recall, and 2-day dietary records were analyzed. Oxidative stress was measured by the levels of diacron reactive oxygen metabolites (d-ROM). Antioxidant status was determined by the biological antioxidant potential (BAP) and levels of endogenous antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase. We observed that vegetarians had a significantly lower body fat percentage ($21.6{\pm}6.4%$) than that of omnivores ($25.4{\pm}4.6%$; $P$ < 0.004). d-ROM levels were significantly lower in vegetarians than those in omnivores ($331.82{\pm}77.96$ and $375.80{\pm}67.26$ Carratelli units; $P$ < 0.011). Additionally, total cholesterol levels in the vegetarians and omnivores were $173.73{\pm}31.42$ mg/dL and $193.17{\pm}37.89$ mg/dL, respectively ($P$ < 0.018). Low-density lipoprotein cholesterol was $101.36{\pm}23.57$ mg/dL and $120.60{\pm}34.62$ mg/dL ($P$ < 0.005) in the vegetarians and omnivores, respectively, indicating that vegetarians had significantly lower lipid levels. Thus, oxidative stress, body fat, and cholesterol levels were lower in long-term vegetarians than those in omnivores.

• 약학회지
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• 제44권3호
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• pp.232-236
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• 2000

An intravenous pharmacokinetics for a new red cell substitute, PEG-hemoglobin SB1, was studied in SD rats. Total-hemoglobin and its metabolite methemoglobin in the plasma were determined using a spectrophotometer. The limit of quantitation was 0.01g/dL and the C.V for interday assay reproducibility was less than 6%. Upon intravenous administration of anticipated clinical dose, 10 ml(0.7 gHb)/kg, plasma concentration curve of total-hemoglobin was well described by one-compartment model. The $t_{\frac{1}{2}},{\;}CL_{t}$, Vd and $AUC^{0-48hr}$ were $8.23{\pm}0.96{\;}hr,{\;}0.06{\;}{\pm}{\;}0.01 {\;}dL/hr/kg,{\;}0.66{\pm}0.05{\;}dL/lg{\;}and{\;}13.6{\;}{\pm}{\;}1.01g{\cdot}hr/dL$, respectively, in male rats(n=5, $mean{\;}{\pm}{\;}SD$). Those parameters in female rats were $9.21{\;}\pm{\;}2.31{\;}hr,{\;}0.06{\;}{\pm}{\;}0.01{\;}dL/hr/kg,{\;}0.79{\pm}{\;}0.08{\;}dL/kg{\;}and{\;}13.0{\;}{\pm}{\;}2.36{\;}g{\cdot}hr/dL$, respectively. Similar kinetic profiles between males and females were also obtained from other parameters. Small amount of methemoglobin, an oxidative metabolite of SB1, was detected in the plasma of both sexes, where the $AUC^{0-48{\;}hr,m}$ and $t_{{\frac{1}{2}},m}$ were approximately $1.5{\;}g{\cdot}hr/dL$ and 20 hr, respectively. The present work provides a critical kinetic data for the effective clinical applications of PEG-hemoglobin SB1.

• 한국산업보건학회지
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• 제11권3호
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• pp.190-197
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• 2001

Noise-induced hearing loss(NIHL) was the highest rate (43.5%~58.5% from 1996 to 1998) of positive findings through specific medical program in Korea. There were much more NIHL at workers of automobile manufacturing factories than other manufacturing factories. The specific aim of the present study was to determine the noise exposure of automobile press lines, according to their job titles, press line types(auto, semiauto), dosimeter parameters setting. There were a total 11 press lines sampled at a automobile manufacturing company. Among those press lines, 10 press lines were autolines with acoustic enclosure, one semiauto press line was no aucostic enclosure Noise exposure data were sampled for an work shift using noise dosimeter, which recorded both time-weighted average(TWA) and 1-min average. The mean OSHA TWA(Korea TWA with threshold 90) was $80.7dB(A){\pm}4.7dB(A)$ for leader, $82.8dB(A{\pm}4.5dB(A)$ for pallette man, $76.7dB(A){\pm}4.3dB(A)$ for press operators, $76.6dB(A){\pm}5.6dB(A)$ for crane operators, $77.1dB(A){\pm}2.8dB(A)$ for forklift drivers, whereas the mean NIOSH TWA was $88.9dB(A){\pm}1.7dB(A)$ for leader, $89.6dB(A){\pm}2.1dB(A)$ for pallette man, $86.7dB(A){\pm}1.8dB(A)$ for press operators, $88.5dB(A){\pm}2.0dB(A)$ for crane operators, $87.7dB(A){\pm}1.0dB(A)$ for forklift drivers. While L10 for NIOSH TWA samples was 84.8 dB(A) ~ 87.3 dB(A), L10 for OSHA TWA samples was 69.5 dB(A) ~ 77.4 dB(A). L10 means that the TWA for 90% of the samples exceeded L10. Among OSHA TWA(Korea TWA with threshold 90) samples for pallette man, 7.7 % exceeded 90 dB(A), the OSHA permissible exposure level, but OSHA TWA samples for the other job titles didn't. Among NIOSH TWA samples, the samples over 85 dB(A), the NIOSH recommended exposure limit, was 100% (leaders), 83.3 %(operators), 97.4%(palletteman), 100%(forklift drivers), 91.7 %(crane operator). The results of One-way random effects analysis of variance models shows that the difference between job titles was significant by OSHA TWA(p<0.05), but not significant by NIOSH TWA(p>0.05). NIOSH TWA samples were significantly higher than OSHA TWA samples(P<0.05). Regression analysis was used to obtain relationships between OSHA TWA samples and NIOSH TWA samples. In this case the coefficient of determination = 0.90, which shows the high degree association between two methods. Regression equation, NIOSH TWA = 0.552 * OSHA TWA + 42.13 dB(A), shows that if OSHA TWA is known, NIOSH TWA can be predicted by the equation. The mean TWA difference between threshold 80 dBA and 90 dBA was significant(p<0.01). While the TWA noise exposures were 7.7% above the Korea(OSHA) PEL, they were more than 83.3% over NIOSH REL. Automobile workers were exposed to noise level that could be potentially damaging to their hearing. It found that there is approximately 25% excess risk of hearing loss even if a worker is protected to the PEL in according to NIOSH study.

• 한국수정란이식학회지
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• 제22권2호
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• pp.111-114
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• 2007

본 연구는 젖소의 산유 능력에 따른 번식 성적을 조사하기 위하여 축산과학원 시험우사에서 사육중인 젖소를 이용하여 분만 후 유즙중 P4농도를 분석하였고, 전문경영체농장 22개 소에서 사육중인 젖소에 대한 번식 기록을 이용하여 고능력우(305일 유량 10,000 kg 이상)와 평균 능력우(305일 유량 10,000 kg이하)의 번식 성적을 조사한 결과는 다음과 같다. 1. 젖소의 분만 후 progesterone peak는 고능력 및 평균 능력우의 경우에 각각 $38.8{\pm}11.1$ 및 $39.6{\pm}9.7$일로 거의 비슷한 결과를 나타내었다. 2. 분만 후 첫 발정까지의 일수는 평균 능력우 및 고능력우가 각각 $99.4{\pm}2.1$일 및 $117.7{\pm}4.2$일로 고능력우가 평균 능력우에 비하여 11.6일 늦어지는 결과를 나타내었고(p<0.01), 분만 후 수태까지의 일수도 평균 능력우 및 고능력우가 각각 $145.9{\pm}3.8$일 및 $165.9{\pm}6.5$일로 고능력우가 평균 능력우에 비하여 20일 늦어지는 결과를 나타내었다(p<0.01). 그리고 분만 간격은 평균 능력우 및 고능력 우가 각각 $421.5{\pm}4.0$일 및 $448.4{\pm}7.2$일로 고능력우가 평균 능력우에 비하여 26.9일 연장되었다(p<0.01).

• 한국조리학회지
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• 제22권6호
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• pp.114-119
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• 2016

This study aimed to investigate changes in the diverse compound in coffee beans under different roasting conditions. Four different kinds of chemical characteristics (phenolic contents, flavonoid contents, chlorogenic acid, and caffeine) were analyzed. According to the temperature of coffee roasting, this study categorized green bean, extract A ($191^{\circ}C$), B ($202^{\circ}C$), C ($220^{\circ}C$), and D ($233^{\circ}C$). As a result, total phenol compound showed low level of total phenol compound at lower temperatures. Extract A showed significantly higher level of total flavonoid ($111.33{\pm}10.14$), green bean showed $83.67{\pm}2.43$, Extract B $46.11{\pm}2.38$, C and D showed $31.44{\pm}0.12$, $19.22{\pm}0.46$ respectively. Green bean showed higher level of chlorogenic acid ($64.47{\pm}0.51$), Extract A ($39.66{\pm}0.47$), extract B ($12.45{\pm}0.99$), C, D ($3.59{\pm}0.31$, $0.63{\pm}0.12$) respectively. This study also noted that there are significant different in terms of caffeine content. Extract A has higher level of caffeine content ($38.45{\pm}1.70$) significantly, green bean ($27.14{\pm}2.27$), extract B ($18.95{\pm}0.64$), extract C ($17.89{\pm}0.96$). As a conclusion, we revealed that roasting conditions play an important role in the composition of coffee compounds.

• 한국안광학회지
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• 제16권2호
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• pp.195-200
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• 2011

목적: 학령기 아동에게 조절마비하 굴절검사를 시행 한 이후 안경착용이 근시진행에 미치는 영향에 대하여 분석하고자 하였다. 방법: 안경착용경험이 없는 8세 이상 12세 이하의 학령기 아동 33명(66안)에 대하여 근시의 진행정도를 알아보기 위하여 조절마비하 굴절검사를 기간별(초기, 100일, 200일, 300일)로 실시하였다. 안경착용군(실험군, 32안)은 최초 조절마비하 굴절검사 이후에 나안시력 0.6에 맞춰 안경을 착용하도록 하였으며 굴절이상도에 따른 안경굴절력은 -0.50 D, -0.75 D, -1.00 D, -1.25 D 그리고 -1.50 D였으며 비안경착용군(대조군, 34안)은 기간별로 조절마비하 굴절검사를 시행하였다. 실험군과 대조군에 대하여 기간별, 연령별, 굴절이상도별로 근시의 진행정도를 비교하였으며, 실험군은 안경착용굴절력값에 따른 근시의 진행정도를 관찰하였다. 결과: 조절마비하 굴절검사 300일을 기준으로, 안경착용군(실험군)에서 평균 등가구면 굴절력 -1.03 ${\pm}$ 0.43D(t=13.36, p<0.001) 증가하였고, 비안경 착용군(대조군)에서는 -0.61 ${\pm}$ 0.35 D(t=10.05, p<0.001) 증가하여 통계학적 유의성이 있었다. 안경처방값에 따라 -1.50 D에서 41.19 ${\pm}$ 15.25%, -1.25 D에서 336.74 ${\pm}$ 19.29%, -1.00 D에서 56.57 ${\pm}$ 20.21%, -0.75 D에서 87.26 ${\pm}$ 49.38%, -0.50 D에서 106.69 ${\pm}$ 59.60%가 증가하였다. 결론: 안경착용군이 비안경착용군보다 300 일을 기준으로 0.46D 더 근시진행이 빨랐으며 근시진행의 완화를 위해서는 안경착용을 하지 않는 것이 효과적이라 사료된다. 그러나, 학령기 아동에게 최초의 안경착용이 필요하다면 조절마비하 굴절검사로부터 300일 이내의 근시진행에 대하여 저교정을 고려해 볼 수 있겠다.

• 한국방사선학회논문지
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• 제13권2호
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• pp.185-192
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• 2019

DXA 검사는 작은 골량의 변화로 발생하는 생물학적 변화를 가장 잘 반영할 수 있어 임상에서 우수한 성능을 발휘하는 골밀도 검사 장치이다. 검사의 정확도와 정밀도의 유지를 위하여 정도관리가 필수적으로 수행되어야 하지만 팬텀의 제작이 어렵고 상대적으로 고가의 가격이기 때문에 병원마다 보유하지 않고 있는 경우가 많다. 따라서 본 연구에서는 3D 프린터 및 시중에서 손쉽게 구할 수 있는 필라멘트의 내부채움 정도의 변화를 이용하여 교차보정 팬텀을 개발하고 상용화된 팬텀과의 비교 평가를 통해 유용성을 평가하였다. 팬텀의 개발을 위해 ABS, TPU, PLA, 30% Cu-PLA, 30% Al-PLA의 HU을 평가하였으며 각각 내부 채움 100%에서 $-149.74{\pm}2.36$, $-55.62{\pm}7.14$, $-7.68{\pm}3.82$, $87.53{\pm}1.07$, $1795.20{\pm}16.15$의 HU를 나타내었다. 선형회귀분석이 적용된 3D 프린팅 팬텀의 L1, L2, L3 골밀도는 $0.620{\pm}0.010g/cm^2$, $1.092{\pm}0.025g/cm^2$, $1.554{\pm}0.026g/cm^2$으로, 기존 팬텀과 통계적으로 높은 관련성을 보였다. 이를 활용한다면, DXA 장치의 적절한 정도관리가 가능할 것이며, FDM 3D 프린팅을 이용한 다양한 의료용 팬텀 제작에 기초 자료로 활용될 것으로 사료된다.

• 한국가구학회지
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• 제25권4호
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• pp.258-267
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• 2014

We present the dendrochronological dates of Korean wooden furnitures in National Museum of Korea. Six of fourteen were successfully dated. Rice Chest (구 2225) was dated A.D. 1805 +. Others dated were Rice Chest (신수 9479; A.D. 1819), Rice Chest (신수 9475; A.D. $1826{\pm}10$), Ganghwa-Chest with a flap door (구 2341; A.D. $1842{\pm}10$), Ganghwa-Chest with a flap door (구 3124; A.D. $1859{\pm}10$), Chest with a flap door (신수 15731; A.D. $1865{\pm}10$). Most of existing cabinets were made in 1800s. Rice Chest (신수 9479) was the earliest piece of furniture in the collections of National Museum. The furniture is usually composed one species. The major species was Pinus densiflora.

• 한국전자파학회논문지
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• 제22권2호
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• pp.173-181
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• 2011

본 논문에서는 출력 단자 간의 격리 특성이 향상된 half mode 기판 집적 도파관(half mode substrate integrated waveguide) 평형 여파기를 제안한다. 제안된 평형 여파기는 중앙 금속 층에 저항성 커플링 슬롯을 삽입하여 출력 단자 간의 격리 특성을 향상시켰으며, 우수한 삽입 손실을 가지며 평형 신호를 다룰 수 있다. 측정 결과, 5.8~6.4 GHz의 주파수 대역에서 삽입 손실 $5.4{\pm}0.2$ dB, 입력 반사 손실은 10 dB 이상으로 나타났다. 또한, 통과 대역내에서 출력 단자 간의 격리 특성이 18 dB 이상으로 나타났으며, 출력 단자 사이의 위상차도 $177{\pm}8^{\circ}$가 나타났다.