• 한국식품과학회지
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• 제22권6호
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• pp.625-631
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• 1990

사과로부터 추출한 산화효소와 5종의 polyphenol 화합물을 반응시켜 얻어진 사과효소 갈변반응 생성물(AEBRP)들의 항돌연변이 효과를 검토하기 위해 발암물질로 알려져 있는 N-methyl-N'-nitro-N-nitrosoguanidine(MNNG), mitomycin C(MMC), 4-nitroquinoline-1-oxide(4NQO), benzo(${\alpha}$)pyrene(B(${\alpha}$)P) 그리고 3-amino-1,4-dimethyl-5H-pyrido(4,3-b) indole(Trp-P-1)에 대한 다섯 종류의 사과효소 갈변반응 생성물들의 돌연변이 억제효과를 검토하였다. Bacillus subtilis Hl7과 M45 두 균주를 이용하는 spore rec-assay에서 homocate-chol-AEBRP와 hydroquinone-AEBRP는 농도증가에 따라 MMC와 MNNG에 대하여 강한 억제효과를 나타내었으며 Salmonella typhimurium TA98과 TA100 두 균주를 이용한 Antimutagenicity test에서는 hydroxyhydro-quinone-AEBRP와 pyrogallol-AEBRP는 S-9mix 첨가시 두 균주에서 Trp-P-1과 B(${\alpha}$)P에 대하여 강한 억제효과를 나타내었다. 그리고 대부분의 AEBRP들은 MNNG로 유도된 TA98주에서 $50%{\sim}80%$의 억제효과를 나타내었으나 hydroxy-hydroquinone-AEBRP를 제외한 네 종류의 AEBRP들은 TA100 균주에서 약 94%의 억제효과를 나타내었다. 한편, 4NQO에 대한 다섯 종류의 AEBRP들의 돌연변이 억제효과는 일반적으로 약한 편이었으며, 특히 homocatechol-AEBRP는 TA98 균주에서 48%의 억제효과를 보였고 TA100 균주에서는 homocatechol-AEBRP와 hydroquinone-AEBRP가 46%에서 58% 정도의 억제효과를 나타내었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제37회 하계학술대회 초록집
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• pp.340-340
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• 2009

• 한국식품과학회지
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• 제37권1호
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• pp.50-54
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• 2005

천연식품보존료의 개발을 목적으로 marta rosemary의 항균활성을 조건을 달리하여 조사하였다. 균주에 따른 에탄올 추출 marta rosemary의 항균성은 S. typhimurium과 B. subtilis에 대하여 높았다. 용매별 항균성은 극성이 작은 butanol과 hexane 추출액에서 높았고. 수용액에서의 항균 활성은 pH 7에서 가장 높았다. 허브의 미생물의 생육억제 양상은 B. subtilis에 대하여 저 농도에서는 유도기 지연형, 고농도에서는 유도기 지연 및 비증 식속도 억제형이었으며 S. typhimurium은 농도에 관계없이 비 증식속도 억제형으로 관찰되었다. 이와 같은 경향은 낮은 pH 에서도 유사하게 나타났다. 항균물질의 $100^{\circ}C$에서의 열안정성은 가열시간이 길수록 허브의 항균력이 저하되었고 $121^{\circ}C$에서 15분간의 열처리로 인한 허브의 항균력은 B. subtilis보다 S. typhimurium에서 높게 나타났다.

• Journal of Nutrition and Health
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• 제15권3호
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• pp.202-211
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• 1982

A modification of a microbiological assay of vitamin $B_{12}$ was made and used to determine the vita­min levels during kimchi fermentation. A cyanide-buffer solution of pH 6.0 replaced the metabisufite-buffer specified in the A.O.A.C. method. The vitamin $B_{12}$ activity was decreased by blending kimchi samples for 5 minutes and retained the activity by steaming for 10 minutes before blending. The alkali hydrolysis of kimchi at pH 12.0 for 30 minutes at $121^{\circ}C$ was sufficient to destroy the vitamin $B_{12}$ and permit the detection of analogs with the same assay organism. Vitamin $B_{12}$ reached a maximum of 47ng/100g during the fermentation of kimchi ${15}\;4^{\circ}C.$ Inoculation of the kimchi with Propionibacterium shermanii (ATCC 13673) increased the vitamin production to a maximum of 102ng/100g at 1 week of fermentation. Soy flour (0.5%) or beef extract (0.05%), which were regarded as protein sources, added to the inoculated kimchi further increased the vitamin $B_{12}$ activity to 197 and 203ng/100g.

• 대한전자공학회논문지SD
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• 제45권8호
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• pp.48-53
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• 2008

본 논문에서는 100 nm InGaAs/InAlAs/GaAs metamorphic HEMT (high electron mobility transistor)를 이용하여 94 GHz 대역 응용에 적용 가능한 MMIC (millimeter-wave monolithic integrated circuit) 저잡음 증폭기를 구현하였다. 94 GHz MMIC 저잡음 증폭기 구현을 위하여 제작된 $100nm\times60{\mu}m$ MHEMT의 측정결과, 655 mA/mm의 드레인 전류 밀도, 720 mS/mm의 최대전달컨덕턴스를 얻었으며, RF 특성으로 전류이득차단주파수는 195 GHz, 최대공진주파수는 305 GHz의 양호한 성능을 나타내었다. 구축된 MHEMT와 CPW 라이브러리를 이용하여 구현된 MMIC 저잡음 증폭기의 측정결과, 94 GHz에서 $S_{21}$ 이득은 14.8 dB, 잡음지수는 4.6 dB의 우수한 특성을 얻었다. 전체 칩의 크기는 $1.8mm\times1.48mm$이다.

• 농촌계획
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• 제26권1호
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• pp.89-99
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• 2020

This study was conducted as a basic research to create a sound and vital ecological environment in the city compared to the appearance characteristics of Gap stream(G-stream), which are the main stream of Banseok stream(B-stream), by analyzing the characteristics of waterbirds, including Wild Spot-billed Duck (S-Duck), that live in B-stream built as ecological stream. The waterbird survey was conducted by the line census for 3.2km, Jukdong-bridge to Jamiseon-bridge, from January to August 2018. The analysis of the survey was conducted with Relative species density(RD) of the emerging waterbird species, the Species diversity and Density Per Unit area for 100㎡(DPU). The waterbird survey results of B-stream was conducted 65 times. The five types of water birds that appeared during the survey were Spot-billed Duck(Anas poecilorhyncha), Teal(Anas crecca), Little Egret(Egretta garzetta), Great Egret(Egretta alba), and Grey Heron(Ardea cinerea). As a result, for S-Duck at B-stream, RD was 89.9%, monthly species diversity was simple as 0.3801 in January, 0.5943 in February and 0.3501 in August. The DPU of the S-Duck was 0.165/100㎡ in the B-Stream survey section which was 4.9 times higher than the main stream section, G-stream. The non-freezing zone of the city's small stream is expected to play an important role as a winter stop for wild birds such as S-Duck during the freezing period of the huge stream. For this reason, considering the ecological characteristics of wild waterbirds such as S-Duck when creating ecological stream, a: space and linear selection of waterways which can minimize the impact of natural enemy and increasing the number of walkers, b: management water-friendly plants in the low flow channel, c: arrangement walking-bicycle road will be necessary.

• 한국동물위생학회지
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• 제41권1호
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• pp.57-61
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• 2018

Canine peripheral nerve sheath tumors (PNSTs) are spindle cell tumors that arise from Schwann cells, perineural cells, fibroblasts or all of them. Based on the morphology and biologic behavior, PNSTs are divided into benign PNST (BPNST) and malignant PNST (MPNST) forms. The aim of this study is to diagnose the two cases of neoplastic tissue samples with features of PNSTs by the histopathology and immunohistochemistry. The study was performed using two specimens from small animal clinic. The first case, A was a mass, 3~4 cm in diameter, extruded from vaginal mucosa of 10-year-old spayed female mixed-breed dog. And the second case, B was a subcutaneous mass, 1.5 cm in diameter, which is originated from right hind leg of 9-year-old castrated male mixed-breed dog. Two cases were stained with hematoxylin and eosin (H&E) for histopathological examination. And also immunohistochemistry (IHC) was performed by the avidin-biotin peroxidase complex (ABC) method with antibodies specific for the following proteins: S-100 protein, smooth muscle actin (SMA) and epidermal growth factor receptor (EGFR). In results, Antoni B schwannoma pattern characterized by pleomorphic, round and fusiform polygonal cells was seen in A. In B, Antoni A pattern, densely packed spindle cells arranged in interlacing bundles was seen in addition to Antoni B pattern. In IHC, cytoplasms of neoplastic cells were diffusely labeled for S-100 expression in A and B. For SMA, both A and B show negative expression. And for EGFR, A shows negative expression but B shows partially positive expression in areas of Antoni B schwannoma pattern. The histopathologic features of two cases coupled with the S-100 immunoreactivity led to a diagnosis of PNST. For SMA, both A and B show negative expression. The diagnosis of A will be a BPNST with the negative result and B will be a MPNST with the positive result for EGFR.

• JSTS:Journal of Semiconductor Technology and Science
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• 제13권2호
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• pp.98-107
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• 2013

This work describes a 13b 100 MS/s 0.13 um CMOS four-stage pipeline ADC for 3G communication systems. The proposed SHA-free ADC employs a range-scaling technique based on switched-capacitor circuits to properly handle a wide input range of $2V_{P-P}$ using a single on-chip reference of $1V_{P-P}$. The proposed range scaling makes the reference buffers keep a sufficient voltage headroom and doubles the offset tolerance of a latched comparator in the flash ADC1 with a doubled input range. A two-step reference selection technique in the back-end 5b flash ADC reduces both power dissipation and chip area by 50%. The prototype ADC in a 0.13 um CMOS demonstrates the measured differential and integral nonlinearities within 0.57 LSB and 0.99 LSB, respectively. The ADC shows a maximum signal-to-noise-and-distortion ratio of 64.6 dB and a maximum spurious-free dynamic range of 74.0 dB at 100 MS/s, respectively. The ADC with an active die area of 1.2 $mm^2$ consumes 145.6 mW including high-speed reference buffers and 91 mW excluding buffers at 100 MS/s and a 1.3 V supply voltage.

• 한국어류학회지
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• 제25권3호
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• pp.149-156
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• 2013

우리나라 망둑어과 어류 중 말뚝망둥어아과에 속하며 형태학적으로 흡사한 짱뚱어 (B. pectinirostris)와 남방짱뚱어(S. gigas)를 대상으로 12S rRNA, 16S rRNA 및 mitochondria cytochrome b 유전자의 염기서열 분석을 통해, 종내 및 종간의 분자유전학적 특성을 파악하고자 하였다. 짱뚱어 종내 개체간 유전적 차이를 밝히기 위해 mitochondria내에 3가지 유전자를 분석한 결과, 순천지역과 군산지역간의 염기서열은 12S rRNA는 총 434 bp (base pair)의 염기서열을 얻었으며 이를 비교 분석한 결과, 순천지역과 군산지역의 집단 간에는 100% 동일한 염기서열을 보였고, 16S rRNA 유전자는 총 484 bp의 염기서열 중 99.6%의 차이로 단지 2 bp가 치환된 것으로 나타났고, mitochondria cytochrome b 유전자의 경우, 444 bp의 염기서열을 얻었으며 두 지역 간 염기서열은 100%의 일치도를 보였다. 한국산 짱뚱어를 대상으로 한 동일한 종내에서 서식지 (서해, 남해)에 따른 유전적 차이나 지리적 거리의 차이가 있을 것으로 예상하였으나 이상의 3가지 유전자를 비교해 본 결과를 종합해 보면, 종내 개체 변이와 지역별 변이는 일어나지 않은 것으로 밝혀졌다. 또한 짱뚱어와 남방짱뚱어 2종간 비교 (inter-species)에서는 순천지역 짱뚱어와 해남지역 남방짱뚱어를 12S rRNA 유전자와 16S rRNA 유전자 및 mitochondria cytochrome b 유전자 염기서열을 비교 분석한 결과, 각각 96.1% (17 bp), 94.0 (29 bp), 그리고 82.9% (76 bp)로 나타나 두 종의 유전학적 차이는 크게 나타났다. 따라서 본 연구에서 나타난 짱뚱어와 남방짱뚱어 두 종간에 3.9~17.1%를 보여 서로 다른 종으로 볼 수 있을 것으로 사료되었다.

• 설비공학논문집
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• 제7권1호
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• pp.63-72
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• 1995

Convective heat transfer in a two-dimensional horizontal and vertical channel with isothermal rectangular beams attached to one adiabatic wall is investigated from the numerical solution of Navier-Stokes and energy equations. The solutions have been obtained for dimensionless beam spacings, S/L=1~4, aspect ratios of beam, H/B=0.25~4, Reynolds numbers, Re=50~1000 and Grashof numbers, $Gr=0{\sim}5{\times}10^4$. The total mean Nusselt number, Nu_T for horizontal and vertical channels shows same value at Gr=0. As Gr increases, Nu_T for horizontal channel increases, but Nu_T for vertical channel shows similar value at S/L=2, H/B=0.25, Re=100. The total mean Nusselt number for horizontal channel is higher than that for vertical channel. As H/B increases, $Nu_T$ for both channel decrease at $Gr=10^4$, Re=100.