• 한국축산식품학회지
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• 제21권1호
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• pp.32-37
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• 2001

The study investigated the effects of protein concentration, EGTA and strength of hydrostatic pressure on pH, viscosity and turbidity for ultra filtrated skim milk retentates. The results showed that hydrostatic pressure treatments up to 600 MPa did not affect the viscosity of skim milk, while the turbidity of skim milk increased at higher than 200 MPa. Addition of EGTA caused reduction in turbidity of skim milk, two times (2SR) and three times (3SR) concentrated skim milk retentates. Viscosity for 2SR and 3SR increased proportionally to the amount of EGTA, but viscosity of skim milk was not influenced by EGTA. High pressure treatment also did not cause any difference in viscosity and turbidity of skim milk. However, this treatment decreased viscosity and turbidity for 2SR and 3SR. In particular, 200 MPa treatment showed to induce a higher decrease in turbidity compared with 400 MPa.

• Journal of Microbiology and Biotechnology
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• 제32권8호
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• pp.1026-1033
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• 2022

This study presents a novel DNA part characterization technique that increases throughput by combinatorial DNA part assembly, solid plate-based quantitative fluorescence assay for phenotyping, and barcode tagging-based long-read sequencing for genotyping. We confirmed that the fluorescence intensities of colonies on plates were comparable to fluorescence at the single-cell level from a high-end, flow-cytometry device and developed a high-throughput image analysis pipeline. The barcode tagging-based long-read sequencing technique enabled rapid identification of all DNA parts and their combinations with a single sequencing experiment. Using our techniques, forty-four DNA parts (21 promoters and 23 RBSs) were successfully characterized in 72 h without any automated equipment. We anticipate that this high-throughput and easy-to-use part characterization technique will contribute to increasing part diversity and be useful for building genetic circuits and metabolic pathways in synthetic biology.

• 한국초전도ㆍ저온공학회논문지
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• 제11권1호
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• pp.30-34
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• 2009

This paper deals with charging and persistent-current mode operating characteristics of BSCCO magnet load using high-temperature superconducting (HTS) power supply. The HTS power supply consists of two heater-triggered switches, an iron-core transformer with the primary copper winding and the secondary BSCCO solenoid, and a BSCCO magnet load. The magnet load was fabricated by double pancake winding and its inductance is about 21 mH. A hall sensor was installed at the middle of the magnet load to measure the current in the load. In order to investigate the efficient pumping characteristics, operating tests of heater-triggered switch with respect to dc heater current were carried out, and the electromagnet current was determined by considering saturation characteristics of its iron core. The saturation characteristics of charged current in the magnet load were observed with respect to various pumping periods: 12 s, 14 s, 24 s and 32 s. After charging the magnet load, the persistent current was measured. The operating characteristics of the persistent current mode were mainly determined by joint resistance and magnet load.

• 한국토양비료학회지
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• 제35권2호
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• pp.69-76
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• 2002

본 연구는 CMS에 함유된 $NH_4{^+}$의 토양 중 행동을 연구하기 위해 $NH_4{^+}$을 중질소 ($^{15}N$)로 표지한 후 수분 불포화 조건과 수분 포화 조건에서 0, 2, 4, 7, 14 및 21일 동안 항온배양 실험을 수행하였다. 불포화 조건의 토양 pH는 6.1에서 5.4로 지속적으로 감소하였고, 포화조건에서는 처리 2일 후 6.5로 증가한 후 일정하게 유지하였다. 암모늄태 질소의 농도는 불포화 조건에서 포화 조건보다 3배 빠르게 감소하였다. 질산태 질소의 농도는 불포화 조건에서는 21일까지 $17.4mg\;kg^{-1}$에서 $155.4mg\;kg^{-1}$으로 지속적으로 증가했지만 포화 조건에서는 낮은 수준(약 $8.0mg\;kg^{-1}$)으로 유지되었다. 항온배양 후 21일에는 불포화 조건에서 처리된 $^{15}NH_4{^+}$는 질산화과정을 거쳐 질산태 질소 형태로 52.4% 존재하였고 포화 조건에서는 1%이하로 존재하였다. 21 후 $NO_3{^-}$의 $^{15}N$ atom % excess는 불포화 조건에서 1.63%, 포화 조건에서는 0.32%였다. 처리된 $^{15}NH_4{^+}$중에서 항온배양 기간동안 부동화된 양은 불포화 조건에서 19.6%, 포화 조건에서는 17.0%였으며, 대부분 처리 후 4일 이내에 부동화되었다. 처리된 $^{15}NH_4{^+}-N$ 중 탈질 등으로 손실되어 최종적으로 회수되지 못한 비율은 불포화 조건에서는 28.4%, 포화 조건에서는 67.6%였다.

• 원예과학기술지
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• 제32권2호
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• pp.157-164
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• 2014

국내에서 유통되고 있는 팽연왕겨(ERH)와 훈탄(CRH)을 포함한 혼합상토를 개발하기 위하여 두 종류 물질 또는 이들을 피트모스(PM) 또는 코이어 더스트(CD)와 혼합한 상토의 물리 화학성을 분석하여 원예용 상토로 적합한 4종류 혼합상토를 선발하였다. 이 후 기비를 첨가한 후 화학성을 분석하여 혼합상토로써의 적합함을 판단하였다. 공극률, 용기용수량 및 기상률에서 ERH는 81.3%, 39.9%, 41.4% 그리고 CRH는 77.6%, 64.1%, 13.5%로 측정되었다. 쉽게 이용할 수 있는 수분(EAW)과 완충수(BW)의 비율은 ERH가 각각 11.37% 및 5.27%로, CRH는 각각 13.5% 및 8.8%였다. 화학적 특성에서 ERH는 pH 7.13, EC $1.31dS{\cdot}m^{-1}$, 양이온교환용량(CEC) 12.1meq${\cdot}100g^{-1}$였지만 CRH는 pH 11.2, EC $6.53dS{\cdot}m^{-1}$, 그리고 CEC 7.79meq${\cdot}100g^{-1}$로 분석되었다. ERH와 CRH를 PM 또는 CD와 다양한 비율로 혼합한 후 원예용 상토로 적합하다고 판단한 네 종류 상토(PM + ERH, 6:4, v/v;CD + ERH, 8:2; PM + CRH, 7:3; CD + CRH 6:4)의 공극률, 용기용수량 및 기상률은 각각 89.2-90.3%, 67.3-81.8%, 그리고 8.3-21.9%의 범위에 포함되었다. 그러나 피트모스가 혼합된 PM + ERH 또는 PM + CRH 혼합상토는 pH가 4.0-4.3, EC가 $0.33-0.36dS{\cdot}m^{-1}$로 강산성 물질이었지만, CD + CRH 상토는 pH 7.4-7.9, EC $0.814-1.282dS{\cdot}m^{-1}$로 pH와 EC가 높았다. 따라서 이들 상토에 포함될 기비의 종류 및 양을 변화시켜 혼합하고 다시 화학적 특성을 분석한 결과 기비로 혼합하기 전과 뚜렷한 차이를 보이지 않았다. 그러나 기비로 혼합된 고토석회나 유황이 상토 pH에 미치는 영향이 매우 느리게 나타남을 고려할 때 우려할 상황은 아니라고 판단하였다.

• 원예과학기술지
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• 제17권2호
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• pp.148-152
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• 1999

본 연구는 단풍색이 황색인 느티나무 신품종을 육성하기 위해, 선발된 개체들의 생육특성 및 단풍시기, 엽내 안토시아닌 및 엽록소 함량 등의 생리적 특성을 구명하고 접목에 의한 단풍색의 접목후대 특성을 조사하고자 실시하였다. 황색 단풍이 드는 계통으로 선발된 'S-4'는 수령 28년생으로 수고 7m, 수관폭은 6m였으며, 엽내 안토시아닌의 함량이 다른 개체들에 비해 높고 단풍이 아름답고 단풍기간이 긴 것으로 나타났다. 또한 'S-14'와 'S-32' 역시 엽내 안토시아닌의 함량이 다른 개체들에 비해 높고 단풍이 황색으로 아름답고 단풍기간이 긴 것으로 나타났다. 선발된 개체들의 접목묘들 공히 모두 엽내 안토시아닌의 함량이 높고 단풍색이 황색으로 나타나 모본의 형질이 접목 후대에 유전되는 것을 알 수 있었다. 본 연구에서 선발된 개체들은 접목을 통해 번식시킨 후 조경용 소재로 보급할 수 있을 것으로 판단되었다.

• 한국자원식물학회지
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• 제32권5호
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• pp.615-632
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• 2019

본 연구는 경상북도 중북부지역 낙동강 중류의 하천 식물상을 밝히고, 생활형을 파악하여 향후 유사지역 하천에서의 관속식물상 조사연구에 기초자료를 제공하고자 실시하였다. 현지조사는 2016년 5월부터 10월, 2017년 4월부터 10월에 걸쳐 영강, 내성천, 병성천, 위천 및 감천 등 5개 하천에서 실시하였고, 조사결과 조사지역에서 생육하는 관속식물은 99과 288속 421종 4아종 39변종 10품종 등 총 474분류군이었다. 이 중 양치식물은 8과 8속 10종 1변종 등 11분류군, 나자식물은 3과 3속 4종 등 4분류군, 쌍자엽식물 73과 217속 312종 3아종 25변종 8품종 등 348분류군, 단자엽식물 14과 60속 95종 1아종 13변종 2품종 등 111분류군으로 나타났다. 특산식물은 5분류군이 조사되었고, 식물구계학적특정종으로 중요도가 높은 III등급 이상을 살펴보면 V등급은 조사되지 않았으며, IV등급 3분류군, III등급 5분류군이 조사되었다. 희귀식물은 7분류군이 조사되었고, 귀화식물은 73분류군으로 조사되었다. 조사지역 소산식물의 생활형 분석결과 Th 159분류군, H 91분류군, HH 68분류군, G 52분류군, N 35분류군, MM 32분류군, M 25분류군, Ch 12분류군, E 1분류군 등으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권8호
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• pp.1183-1188
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• 2008

The present study aimed to determine the effects of different storage materials and storage period on some hatchability traits of Japanese quail (Coturnix coturnix japonica) eggs. A total of 32 male and 102 female quail (twelve weeks of ages) were housed in multiple-bird cages. Eggs laid were divided into three groups with respect to the period of storage (I = 1st, 2nd and 3rd days, II = 6th, 7th and 8th days, III = 12th, 13th and 14th days) prior to incubation. A total of 816 eggs was stored in 3 different storage environments during each storage period (B = no use of any storage material, P = use of perlite, H = use of hay) and kept in environmental conditions, where the temperature was $21^{\circ}C$ and relative humidity was 75%, prior to incubation. Statistical analyses were performed after the exclusion of values pertaining to non-fertile eggs (190 eggs) from the data set. The fertility rate of the eggs in the experiment was 76.7%. In the present study, the influence of storage material and different storage periods on egg weight loss were found to be statistically significant (p<0.01). Upon the comparison of hatchability of fertile eggs values, the influence of storage material was determined to be significant (p<0.05), and the influence of storage period was demonstrated to be significant (p<0.01). The storage materials used were determined not to have any influence on early and late embryonic death rates. Perlite was concluded to be safe for use in the storage of hatching eggs. The extension of the storage period (more than 8 days) resulted in decreased hatchability values of fertile eggs in each group.

• Asian-Australasian Journal of Animal Sciences
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• 제19권4호
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• pp.568-572
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• 2006

The effect of dietary lysine supplementation on the performance of crossbred lactating sows (n = 49, total 92 litters) and suckling piglets during the warm and cool seasons was studied. Sows were randomly allocated to one of two experimental diets, which were fed throughout a 28-day lactation period. Two diets were formulated based on corn-soybean meal with 6% wheat bran, containing 15% crude protein, and with or without 0.25% lysine-HCl supplementation. No interaction was observed between season and dietary lysine supplementation. Dietary lysine supplementation significantly (p<0.05) increased weaning weight (7.11 vs. 6.46 kg) and daily gain (0.20 vs. 0.18 kg) of piglets. During the warm season lactating sows had significantly lower feed intake (3.78 vs. 6.11 kg, p<0.01), higher weight loss (19.81 vs. 9.73 kg, p<0.01) and backfat loss (0.23 vs. 0.06 cm, p<0.01), longer interval from weaning to estrus (9.32 vs. 6.21 days, p<0.05), lower litter weight gain (42.13 vs. 52.90 kg, p<0.01) and lower daily gain (0.17 vs. 0.21 kg, p<0.01) than lactating sows during the cool season. The results indicate that the influences of dietary treatment and season were independent. The 15.0% CP lactation diet with 0.25% lysine-HCl supplementation did not improve the performance of lactating sows and litter piglets, which was impaired by the warm season.

• Asian-Australasian Journal of Animal Sciences
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• 제33권5호
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• pp.778-787
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• 2020

Objective: This study was conducted to investigate the effects of normal and heat stress environments on growth performance and, selected physiological and immunological parameters, caecal microflora and meat quality in Cobb 500 and Ross 308 broilers. Methods: One-hundred-and-twenty male broiler chicks from each strain (one-day-old) were randomly assigned in groups of 10 to 24 battery cages. Ambient temperature on day (d) 1 was set at 32℃ and gradually reduced to 23℃ on d 21. From d 22 to 35, equal numbers of birds from each strain were exposed to a temperature of either 23℃ throughout (normal) or 34℃ for 6 h (heat stress). Results: From d 1 to 21, strain had no effect (p>0.05) on feed intake (FI), body weight gain (BWG), or the feed conversion ratio (FCR). Except for creatine kinase, no strain×temperature interactions were observed for all the parameters measured. Regardless of strain, heat exposure significantly (p<0.05) reduced FI and BWG (d 22 to 35 and 1 to 35), immunoglobulin Y (IgY) and IgM, while increased FCR (d 22 to 35 and 1 to 35) and serum levels of glucose and acute phase proteins (APPs). Regardless of temperature, the Ross 308 birds had significantly (p<0.05) lower IgA and higher finisher and overall BWG compared to Cobb 500. Conclusion: The present study suggests that the detrimental effects of heat stress are consistent across commercial broiler strains because there were no significant strain×temperature interactions for growth performance, serum APPs and immunoglobulin responses, meat quality, and ceacal microflora population.