• 대한치과교정학회지
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• 제35권2호
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• pp.127-136
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• 2005

광도 차이를 보이지 않았지만 전기도금한 선재 (p<0.001). 스테인레스스틸 선재 (p <0.05). 구리 (p<0.001) 는 배지만을 첨가한 경우보다 통계적으로 유의한 흡광도 감소를 보였다 ISO 10993, part 5에 따라 구리는 "강한 독성"을 보이는 반면 티타늄과 스테인레스스틸 선재는 "무독성". 그리고 전기도금 선재는 "중등도 독성"으로 나타났다 이상의 결과는 전기도금을 이용하여 교정용 선재의 직경을 증가시키는 방법이 임상에 적용되기 위해서는 세포독성을 줄이기 위한 추가의 연구가 필요함을 시사하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.389-390
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• 2012

In this study, we fabricate a superhydrophobic surface made of hierarchical nanostructures that combine wax crystalline structure with moth-eye structure using vacuum cluster system and measure their hydrophobicity and durability. Since the lotus effect was found, much work has been done on studying self-cleaning surface for decades. The surface of lotus leaf consists of multi-level layers of micro scale papillose epidermal cells and epicuticular wax crystalloids [1]. This hierarchical structure has superhydrophobic property because the sufficiently rough surface allows air pockets to form easily below the liquid, the so-called Cassie state, so that the relatively small area of water/solid interface makes the energetic cost associated with corresponding water/air interfaces smaller than the energy gained [2]. Various nanostructures have been reported for fabricating the self-cleaning surface but in general, they have the problem of low durability. More than two nanostructures on a surface can be integrated together to increase hydrophobicity and durability of the surface as in the lotus leaf [3,5]. As one of the bio-inspired nanostructures, we introduce a hierarchical nanostructure fabricated with a high vacuum cluster system. A hierarchical nanostructure is a combination of moth-eye structure with an average pitch of 300 nm and height of 700 nm, and the wax crystalline structure with an average width and height of 200 nm. The moth-eye structure is fabricated with deep reactive ion etching (DRIE) process. $SiO_2$ layer is initially deposited on a glass substrate using PECVD in the cluster system. Then, Au seed layer is deposited for a few second using DC sputtering process to provide stochastic mask for etching the underlying $SiO_2$ layer with ICP-RIE so that moth-eye structure can be fabricated. Additionally, n-hexatriacontane paraffin wax ($C_{36}H_{74}$) is deposited on the moth-eye structure in a thermal evaporator and self-recrystallized at $40^{\circ}C$ for 4h [4]. All of steps are conducted utilizing vacuum cluster system to minimize the contamination. The water contact angles are measured by tensiometer. The morphology of the surface is characterized using SEM and AFM and the reflectance is measured by spectrophotometer.

• Nutrition Research and Practice
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• 제1권2호
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• pp.113-119
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• 2007

Zn is an essential nutrient that is required in humans and animals for many physiological functions, including immune and antioxidant function, growth, and reproduction. The present study evaluated whether Zn deficiency would negatively affect bone-related enzyme, ALP, and other bone-related minerals (Ca, P and Mg) in rats. Thirty Sprague Dawley rats were assigned to one of the three different Zn dietary groups, such as Zn adequate (ZA, 35 mg/kg), pair fed (PF, 35 mg/kg), Zn deficient (ZD, 1 mg/kg) diet, and fed for 10 weeks. Food intake and body weight were measured daily and weekly, respectively. ALP was measured by spectrophotometry and mineral contents were measured by inductively coupled plasma-mass, spectrophotometer (ICP-MS). Zn deficient rats showed decreased food intake and body weight compared with Zn adequate rats (p<0.05). Zn deficiency reduced ALP activity in blood (RBC, plasma) and the tissues (liver, kidney and small intestine) (p<0.05). Also, Zn deficiency reduced mineral concentrations in rat tissues (Ca for muscle and liver, and Mg for muscle and liver) (p<0.05). The study results imply the requirement of proper Zn nurture for maintaining bone growth and formation.

• 한국미생물·생명공학회지
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• 제45권4호
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• pp.343-353
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• 2017

In the present study, the isolation of selenium (Se)-enriched bacteria from rumen fluid and hot spring water was carried out. Rumen fluid samples were taken from cannulated goats fed a basal diet and the water samples were collected from Selayang hot spring, Selangor-Malaysia. A total number of 140 Se-tolerant isolates were obtained aerobically using an Se-enriched medium and spread plate technique. All the isolates were initially screened for the ability to transform the Se-containing medium to a red-orange culture using a spectrophotometer. Twenty isolates of dark red-orange medium were selected for a screening of the highest Se-containing protein accumulating strains using the dialysis technique and icp.ms to measure the Se content. Four isolates, identified as Enterobacter cloacae (ADS1, ADS7, and ADS11), and Klebsiella pneumoniae (ADS2) from rumen fluid origin, as well as, one isolate from hot spring water (Stenotrophomonas maltophilia (ADS18)), were associated with the highest biomass organic Se-containing protein when grown in a medium enriched with $10{\mu}g/ml$ sodium selenite. In addition, around $50{\mu}g/100{\mu}g$ of the absorbed inorganic Se was accumulated as an organic form. Organic Se-containing protein in all the selected strains showed antioxidant properties in the range of 0.306 to 0.353 Trolox equivalent antioxidant capacity (TEAC) mg/ml. Therefore, these strains may offer a potential source of organic Se due to their Se-tolerant nature and higher biomass organic to inorganic Se ratio.

• 한국식품영양학회지
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• 제18권3호
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• pp.254-264
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• 2005

This study was conducted to estimate the contents of heavy metals 'Hg, Cd, Pb, As, Zn, Cu, Cr, Mn' in some vegetables which were produced in Korea. The levels of heavy metals were determined using a mercury analyzer, an ICP(inductively coupled plasma spectrometer) and an AAS(atomic absorption spectrophotometer) after wet digestion. The values of heavy metals "mean(mini.~maxi.)" ppm(mg/kg) in some vegetables(raw of perilla leaf, chard, small water dropwort, water dropwort, kale, bud of aralia, pumpkin(round type) and pumpkin(long type) were as follows : Hg : 0.0021(0.0006~0.0054)mg/kg, Cd : 0.0035(ND*~0.0377)mg/kg, Pb : 0.0191(0.0023~0.0928)mg/kg, As : 0.0757(ND~0.5294)mg/kg, Zn : 2.6299(0.4478~6.8567)mg/kg, Cu : 1.0261(0.2046~8.9417)mg/kg, Cr : 0.1535 (0.0240~0.4982)mg/kg, Mn : 3.2476(0.3283~9.8280)mg/kg. This results showed that Mn was generally simillar to previous reports and Cd, Hg, Pb were lower than other reseaches, but As was little higher or Zn, Cu, Cr were higher than the levels of those reported contents in some vegetables on domestic supermarkets in Korea, Although tolerable limit of Hg and Cd is not in a regulation of WHO/FAO, these mean levels(Pb, As, Zn, Cu) are lower than recommended levels of WHO/FAO, Pb "0.1~2.0" mg/kg, As "1.0" mg/kg, Zn "5.0" mg/kg and Cu "0.1~50"mg/kg from vegetables in 'the tolerable contents of food' by the FAO/WHO, therefor some vegetables has set to evaluate their safeties.

• 동아시아식생활학회지
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• 제15권4호
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• pp.465-474
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• 2005

This study was conducted to estimate the contents of heavy metals 'mercury(Hg), cadmium(Cd), lead(Pb), arsenic(As), zinc(Zn), copper(Cu), chrome(Cr) and manganese(Mn)' in root vegetables which were produced in Korea. The levels of heavy metals were determined using a mercury analyzer, an ICP(inductively coupled plasma spectrometer) and an AAS(atomic absorption spectrophotometer) after wet digestion. The values of heavy metals 'mean(minimum-maximum)' mg/kg(ppm) in root vegetables (radish, turnip, carrot, ginger, edible burdock, taro, Chinese yam, east indian lotus) were as follows ; Hg : 0.0019(0.0002${\~}$0.0062), Cd : 0.0088(ND${\~}$0.0402), Pb : 0.021(ND${\~}$0.1070), As : 0.0401(ND${\~}$0.1732), Zn : 1.865(0.4186${\~}$6.9319), Cu : 0.648 (0.1826${\~}$4.0172), Cr : 0.121(0.0132${\~}$1.2030), and Mn : 2.730(0.0477${\~}$10.0468) mg/kg. These results showed that Hg were generally similar to and Cd was lower but Ph, As, Zn, Co, Mn were little higher than the levels of those reported contents in root vegetables on retail markets in Korea. Although the tolerable limit of Cd and Hg is not set in a regulation of WHO/FAO, the tested mean levels(Pb, As, Zn, Cu) were lower than the regulated ones of WHO/FAO, Pb '0.1-2.0', As '1.0', Zn '5.0', and Cu 0.1${\~}$50 mg/kg from vegetables. Therefore, root vegetables sold in the retail markets were evaluated as safe in terns of the heavy metal contents.

• 대한한방내과학회지
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• 제22권2호
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• pp.193-198
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• 2001

This study was designed to investigate the effects of Korean Lycii Fructus water extract in Pb-administered rats. The Pb exposed rats were given 100 ppm and 200 ppm in the distilled water. Sixty male Sprague-Dawley rats weighing between 90 and 110g were blocked into 6 groups according to body weight. The control group was fed a normal diet, without lead. The experimental groups, which was fed a normal diet plus 100 ppm and 200 ppm lead, and one group received a normal diet plus Lycii Fructus water extracts. The results: the Food intake, the weight gain, and the kidney weight content in the cadmium added groups were lower than those in the Lycii Fructus water extracts group. The contents of Pb in the kidneys of the rats were determined by using ICP(lnductively Coupled Plasma Spectrophotometer). The accumulation of lead in the kidney was lower in the Lycii Fructus water extracts group. The Plasma levels of renin activity was higher in the lead administration groups, as compared with the Lycii Fructus water extracts. Plasma levels of aldosterone activity was higher in the lead administration group, as compared with Lycii Fructus water extracts. These results suggest that Lycii Fructus water extracts has a lowering effects on the accumulation of pb on kidney and it is believed that the Lycii Fructus water extracts have some protective effects on lead-induced nephrotoxicity in rats, but the mechanism of these effects was obscure.

• 한국식품영양과학회지
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• 제27권5호
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• pp.980-986
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• 1998

The effects of mungbean sprout juice on cadmium-induced hepatotoxicity in rats were investigated. Sprague-Dawley rats weighing about 90g were divided into 4 groups and raised for 6 weeks. ; control group(CON), mungbean sprouts juice-administered group(MSJ), cadmium-administered group(CAD) fed water containing 40 ppm cadmium chloride and mung bean sprouts juice and cadmium-administered group(MCD). The diet was supplied every day for the measurement of feed efficiency ratio(FER) and net weight gain was measured every 3 days. The activities of serum glutamic oxaloactic transaminase(GOT) and glutamic pyruvic transaminase(GPT), superoxide dimutase(SOD), catalase and glutathione peroxidase(GSH-Px) in the liver and the hepatic contents of glutathione were examined. The contents of Cd in liver and kidney of the rats were determined by using ICP(Inductively Coupled Plasma Emission Spectrophotometer). Growth rate and FER were decreased in CAD group, compared with CON group but the changes were not significant in MCD group. The activities of serum GOT and GPT, SOD, catalase and GSH-Px in the liver were increased by Cd administration, but the alterations were decreased by supplementation with mungbean sprouts juice. The level of glutathione decreased in CAD group(26.8$\pm$9.0mg/g liver), whereas it increased in MCD group(36.4$\pm$15.8mg gliver). The content of Cd in the liver and kidney in MCD group(9.57 ppm, 4.88 ppm) was decreased, compared with CAD group(12.81 ppm, 5.46 ppm). This result suggested that mungbean sprout juice has a lowering effect on the accumulation of Cd in the liver and kidney and it is believed that the juice has some protective effects to Cd-induced hepatotoxicity in rats, but the mechanism of these effects was obscure.

• 한국식품과학회지
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• 제37권3호
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• pp.329-333
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• 2005

본 연구는 국내 유통 중인 인삼 및 인삼제품류 8종 100건에 대하여 중금속 함량을 조사 평가하고자 수행하였다. 유도결합 플라즈마분광기(ICP), 원자흡광광도계(AAS) 및 수은분석기 둥을 이용하여 납, 카드뮴 등 중금속을 측정하였다. 인삼(n=30) 중 납 등 중금속 함량은 다음과 같았다[min-mak(mean), 단위 mg/kg]. Hg은 0.002-0.02(0.007), Pb은 0.018-0.39(0.106), Cd은 0.004-0.413(0.106), As는 불검출 -0.094(0.013), Cu는 0.24-5.5(3.2), Mn 3.18-50.4(20.09), Zn은 0.76-44.27(13.42). 또한 인삼제품류 (n=70)에 대한 중금속 함량은 다음과 같았다[min-max(mean), 단위 mg/kg]. Hg은 0.0001-0.002(0.001), Pb은 0.001-0.133(0.017), Cd는 불검출 -0.181(0.008), Cu는 불검출 -1.1(0.13), Mn 0.73-30.15(1.61), Zn은 0.02-13.42(1.02). 본 연구결과, 우리나라 국민의 인삼 및 인삼제품류를 통한 수은, 납, 카드뮴 섭취량은 FAO/WHO에서 설정한 잠정주간섭취허용량의 0.003%, 0.01%, 0.02%로 매우 낮게 나타났다.

• 한국식품과학회지
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• 제34권6호
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• pp.992-997
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• 2002

본 연구는 우리나라 식품공전의 당류 중 중금속 함유량을 파악하여 식품공전 제 개정시 과학적 기초자료로 활용하고자 수행하였다. 1999년에 총 285건의 당류에 대하여 ICP, AAS 및 Mercury analyzer 등을 이용하여 납 등 중금속함량을 측정하였으며 그 결과는 다음과 같다. [최소${\sim}$최대(평균), mg/kg]; Hg: 불검출${\sim}0.006(0.001)$, Pb: 불검출${\sim}0.47(0.03)$, Cd: 불검출${\sim}0.06(0.005)$, As: 불검출${\sim}0.10(0.004)$, Cu: 불검출${\sim}1.89(0.15)$. 본 조사결과는 외국의 모니터링 결과와 유사한 것으로 나타났다. 또한 당류를 통한 우리나라 국민의 납, 카드뮴, 수은의 섭취량은 FAO/WHO에서 중금속 안전성 평가를 위해 정한 PTWI의 $0.004{\sim}0.1%$로 안전한 수준이었다.