• 한국식품위생안전성학회지
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• 제33권2호
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• pp.118-123
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• 2018

본 연구에서는 우리나라 식품공전에서 불검출 물질로 관리하고 있는 니트로빈(nitrovin)에 대해 고감도 정량 정성분석이 가능한 LC-MS/MS를 적용하여 적합한 분석법을 제시하고자 하였다. 수산물 시료는 아세토니트릴/물로 추출하고 아세토니트릴 포화 헥산으로 지방을 제거하여 고상추출 카트리지를 적용하여 정제하였다. 분석물질은 전기분무이온화방법의 positive mode에서 이온화하여 MRM 조건을 확립하여 분석하였다. 개선된 시험법은 CODEX CAC/GL-71 가이드라인에 따라서 정확성, 정밀성, 직선성, 정량한계에 대한 검증을 통하여 유효성을 확인하였다. 본 실험에서의 정량한계는 0.001 mg/kg 수준이며, 정량한계를 포함하는 표준시료에서 얻어진 검량선의 상관계수($r^2$)는 0.985 이상으로 시험법의 직선성이 유효함을 판단할 수 있었다. 또한, 수산물(넙치, 장어 및 새우) 시료에 대한 니트로빈의 평균 회수율과 변동 계수는 72.1~122%, 2.9~16.9%로 확인되어 정확성 및 정밀성이 CODEX가이드라인에 부합하였다. 따라서, 개선된 니트로빈 정량분석법은 수산물 중 니트로빈을 분석하는데 적합하며, 니트로빈에 대한 지속적인 잔류실태조사에 활용되어 수산물 중 니트로빈의 안전관리에 기여할 것으로 판단된다.

• Nutritional Sciences
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• 제9권4호
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• pp.233-239
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• 2006

Porous matrices of bioactive polymers such as polyglycolic acid (PGA) or polylactic acid (PLA) can be used as scaffolds in bone tissue growth during bone repair process. These polymers are highly porous and serve as a template for the growth and organization of new bone tissues. We evaluated the effect of PGA and PLA polymers on osteoblastic MC3T3-E1 cell extracellular mineralization. MC3T3-E1 cells were cultured in a time-dependent manner -1, 15, 25d as appropriate - for the period of bone formation stages in one of the five culture circumstances, such as normal osteogenic differentiation medium, PGA-plated, fetal bovine serum (FBS)-plated, PGA/FBS-coplated, and PLA-plated For the evaluation of bone formation, minerals (Ca, Mg, Mn) and alkaline phosphatase activity, a marker for osteoblast differentiation, were measured Alizarin Red staining was used for the measurement of extracellular matrix Ca deposit During the culture period, PGA-plated one was reabsorbed into the medium more easily and faster than the PLA-plated one. At day 15, at the middle stage of bone formation, cellular Ca and Mg levels showed higher tendency in PGA- or PLA-plated treatments compared to non-plated control and at day 25, at the early late stage of bone formation, all three cellular Ca, Mg or Mn levels showed higher tendency as in order of PGA-related treatments and PLA-plated treatments, compared to control even without significance. Medium Ca, Mg or Mn levels didn't show any consistent tendency. Cellular ALP activity was higher in the PGA- or PLA-plated treatments compare to normal osteogenic medium treatment PGA-plated and PGA/FBS-plated treatments showed better Ca deposits than other treatments by measurement of Alizarin Red staining, although PLA-plated treatment also showed reasonable Ca deposit. The results of the present study suggest that biodegradable material, PGA and also with less extent for PLA, can be used as a biomaterial for better extracellular matrix mineralization in osteoblastic MC3T3-E1 cells.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제10권4호
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• pp.299-308
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• 2004

최근 단백질 및 도메인과 관련된 방대한 양의 데이타들이 인터넷상에 공표되고 축적됨에 따라, 단백질간의 상호작용에 대한 예측 시스템의 필요성이 제기되고 있다. 본 논문에서는 이러한 데이타를 이용하여 계산적으로 도메인 조합 쌍에 기반하여 단백질의 상호작용 확률을 예측하는 새로운 단백질 상호작용 예측 시스템을 제안한다. 제안된 예측 시스템에서는 기존의 도메인 쌍(domain pair)의 제약성을 극복하기 위하여 도메인 조합(domain combination)과 도메인 조합 쌍(domain combination pair)의 개념이 새롭게 도입하였다. 그리고 도메인 조합 쌍(domain combination pair 또는 dc-pair)을 단백질 상호작용의 기본 단위로 간주하고 예측을 시도한다. 예측 시스템은 크게 예측 준비 과정과 서비스 과정으로 구성되어 있다. 예측 준비 과정에서는 상호작용이 있는 것으로 알려진 단백질 쌍 집합과 상호작용이 없는 것으로 추정되는 단백질 도메인 쌍 집합으로부터 각각 도메인 조합 정보와 그 출현 빈도를 추출한다. 추출된 정보들은 출현 확률 배열(Appearance Probability Matrix 또는 AP matrix)로 불리는 배열 구조에 저장된다. 논문에서는 출현 확률 배열에 기반을 두어, 단백질-단백질 상호작용을 예측하는 확률식 PIP(Primary Interaction Probability)를 고안하고, 고안된 확률식을 이용하여, 상호작용이 있는 것으로 알려진 단백질 쌍 집합과 상호작용이 없는 것으로 추정되는 단백질 도메인 쌍 집합의 확률 값 분포를 생성시킨다. 예측서비스 과정에서는 예측 준비 과정에서 얻어진 분포와 확률식을 이용하여 임의의 단백질 쌍의 상호작용 확률을 계산한다. 예측 모델의 유효성은 효모(yeast)에서 상호작용이 있는 것으로 보고된 단백질 쌍 집합과 상호작용이 없는 것으로 추정되는 단백질 쌍 집합을 이용하여 검증하였다. DIP(Database of Inter-acting Proteins)의 상호작용이 있는 것으로 알려진 효모 단백질 쌍 집합의 80%를 학습 집단으로 사용했을 때, 86%의 sensitivity와 56%의 specificity를 나타내어, 도메인을 기반으로 한 기존의 예측 시스템에 비해서 우월한 예측 정확도를 보여주었다. 이와 같은 예측 정확도의 개선은 본 예측 시스템이 상호작용의 기본 단위로 dc-pair를 채택한 점과 분류를 위하여 새롭게 고안하여 사용한 PIP식이 유효했던 것으로 판단된다.

• 한국해양공학회지
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• 제27권5호
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• pp.99-104
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• 2013

Recently, various nanoparticles have been used for filler in polymer matrices. The particles of nano size are whether high or not cross-link density in polymer affects the thermal and mechanical properties of one. The properties change as a result of chemical reactions between the nanoparticles and the surface of the polymer. There are two models for nanocomposites: "repulsive interaction" and "attractive interaction" between the nanoparticles and matrix. In this study, the variation in the curing mechanism was examined when nano-size $TiO_2$ was dispersed into an epoxy (Bisphenol A, YD-128) with different curing agents. The results of this study showed that the exothermic temperature and Tg in the case of the nanoparticles used (Jeffamine) (D-180) at room temperature were reduced by an increase in the $TiO_2$ contents because of the "repulsive interaction" between the nanoparticles and the matrix. The tensile strengths were increased by increasing amounts of $TiO_2$ until 3 wt% because of a dispersion strengthening effect caused by the nanoparticles, because of the repulsive interaction. However, such tensile properties decreased at 5 wt% of $TiO_2$, because the $TiO_2$ was agglomerated in the epoxy. In contrast, in the case of the nanoparticles that used NMA and BDMA, the exothermic temperature and Tg tended to rise with increasing amounts of $TiO_2$ as a result of the "attractive interaction." This was because the same amounts of $TiO_2$ were well dispersed in the epoxy. The tensile strength decreased with an increase in the $TiO_2$ contents. In the general attractive interaction model, however, the cross-link density was higher, and tensile strength tended to increase. Therefore, for the nanoparticles that used NMA, it was difficult to conclude that the result was caused by the "attractive model."

• Asian-Australasian Journal of Animal Sciences
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• 제32권12호
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• pp.1836-1843
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• 2019

Objective: Social genetic effects (SGE) are an important genetic component for growth, group productivity, and welfare in pigs. The present study was conducted to evaluate i) the feasibility of the single-step genomic best linear unbiased prediction (ssGBLUP) approach with the inclusion of SGE in the model in pigs, and ii) the changes in the contribution of heritable SGE to the phenotypic variance with different scaling ${\omega}$ constants for genomic relationships. Methods: The dataset included performance tested growth rate records (average daily gain) from 13,166 and 21,762 pigs Landrace (LR) and Yorkshire (YS), respectively. A total of 1,041 (LR) and 964 (YS) pigs were genotyped using the Illumina PorcineSNP60 v2 BeadChip panel. With the BLUPF90 software package, genetic parameters were estimated using a modified animal model for competitive traits. Giving a fixed weight to pedigree relationships (${\tau}:1$), several weights (${\omega}_{xx}$, 0.1 to 1.0; with a 0.1 interval) were scaled with the genomic relationship for best model fit with Akaike information criterion (AIC). Results: The genetic variances and total heritability estimates ($T^2$) were mostly higher with ssGBLUP than in the pedigree-based analysis. The model AIC value increased with any level of ${\omega}$ other than 0.6 and 0.5 in LR and YS, respectively, indicating the worse fit of those models. The theoretical accuracies of direct and social breeding value were increased by decreasing ${\omega}$ in both breeds, indicating the better accuracy of ${\omega}_{0.1}$ models. Therefore, the optimal values of ${\omega}$ to minimize AIC and to increase theoretical accuracy were 0.6 in LR and 0.5 in YS. Conclusion: In conclusion, single-step ssGBLUP model fitting SGE showed significant improvement in accuracy compared with the pedigree-based analysis method; therefore, it could be implemented in a pig population for genomic selection based on SGE, especially in South Korean populations, with appropriate further adjustment of tuning parameters for relationship matrices.

• 대한조선학회논문집
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• 제30권3호
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• pp.116-126
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• 1993

대형구조계의 진동해석에 효율적인 방법으로 알려진 부분구조 진동형 합성방법을 방법론적 관점에서 분류하면 부분구조계간의 연결부 경계조건을 어떻게 가정하는가에 따라 구속모드방법, 불구속 모드방법 및 혼합방법으로 대별할 수 있다. 이 방법들 중에서 불구속 모드방법이 보다 효율적이고 또 특정 부분구조의 실험결과 이용이 용이한 장점이 있으나 정확도가 떨어진다는 단점이 있다. 본 연구에서는 대형 구조계의 진동해석에 효율적이면서 정확도 높은 결과를 얻을 수 있는 불구속 모드방법을 정식화하였다. 불구속 모드방법의 정확도 향상 방안으로서 모드합성시 배제된 고차진동형의 영향을 잉여강성과 더불어 잉여관성 효과도 고려하여 보상하였고, 또 주파수이동기법을 도입하므로써 주관심 주파수 부근에서 더욱 정확도가 높은 결과를 얻을 수 있도록 함과 동시에 부분구조계가 semi-definite system일 경우 특이매트릭스를 처리해야 하는 문제점도 해결하였다. 상기방법의 정확도 및 계산효율성은 선체 2차원 단순화 모델을 포함한 일련의 유한요소모델에 대해 검증되었다. 상기방법에 의한 계산결과는 정확도에 있어서 진동형 합성에 이용된 부분구조계의 최고차 진동수 이하에서는 전체계를 직접 유한요소해석한 경우와 대등하고, 구속모드방법보다 효율적이면서 정확도가 더 높은 결과를 얻을 수 있음이 확인되었다.

• 지역연구
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• 제37권3호
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• pp.3-18
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• 2021

4차 산업혁명이 지역의 산업구조를 변화시키면서, 지역의 특성을 반영한 새로운 산업과 기술의 발전이 요구되고 있다. 본 연구의 목적은 부산, 울산, 경남을 대상으로 지식 간 연관성과 기술의 복합성을 측정하고 지역의 산업 차별화 전략의 가능성이 있는 기술을 파악하는 것이다. 2015~2019년의 특허 자료를 이용하여 652개의 IPC 코드에서 동시출현행렬을 도출하고 지식 간 연관성과 기술의 복합성 지수를 계산하였다. 지식 간 연관성을 이용하여 네트워크 분석을 시행하였다. 분석 결과 동남권의 중심지식은 기계 부문이 큰 비중을 차지하였으며 화학과 전기 부문이 뒤를 이었다. 지역 산업의 차별화 가능성이 있는 기술을 도출하기 위해 위험-편익 프레임워크를 적용한 결과 저위험-고편익의 기술 역량은 상이하게 나타났다. 부산은 기계공학 중 엔진, 기계조작, 운송 등의 기술이 울산은 화학의 환경기술과 재료, 기계공학의 열처리 기술이 저위험-고편익의 역량을 가진 기술로 나타났다. 경남은 김해, 양산, 창원 등에서 기계공학, 화학, 전기공학 일부 기술 등에서 역량이 나타났다. 본 연구의 결과는 지역 내 잠재된 지식을 기반으로 하여 지역성장을 위한 전략 산업의 선정과 도출에 가능성이 있는 기술을 파악하였다는데 의의가 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권10호
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• pp.1501-1510
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• 2019

Objective: An experiment was conducted to evaluate genetic diversity of 26 Chinese indigenous goats by 30 microsatellite markers, and then to define conservation priorities to set up the protection programs according to the weight given to within- and between-breed genetic diversity. Methods: Twenty-six representative populations of Chinese indigenous goats, 1,351 total, were sampled from different geographic regions of China. Within-breed genetic diversity and marker polymorphism were estimated calculating the mean number of alleles, observed heterozygosities, expected heterozygosities, fixation index, effective number of alleles and allelic richness. Conservation priorities were analyzed by statistical methods. Results: A relatively high level of genetic diversity was found in twenty-four population; the exceptions were in the Daiyun and Fuqing goat populations. Within-breed kinship coefficient matrices identified seven highly inbred breeds which should be of concern. Of these, six breeds receive a negative contribution to heterozygosity when the method was based on proportional contribution to heterozygosity. Based on Weitzman or Piyasatian and Kinghorn methods, the breeds distant from others i.e. Inner Mongolia Cashmere goat, Chengdu Brown goat and Leizhou goat obtain a high ranking. Evidence from Caballero and Toro and Fabuel et al method prioritized Jining Gray goat, Liaoning Cashmere goat, and Inner Mongolia Cashmere goat, which agree with results from Kinship-based methods. Conclusion: Conservation priorities were determined according to multiple methods. Our results suggest Inner Mongolia Cashmere goat (most methods), Jining Gray goat and Liaoning Cashmere goat (high contribution to heterozygosity and total diversity) should be prioritized based on most methods. Furthermore, Daiyun goat and Shannan White goat also should be prioritized based on consideration of effective population size. However, if one breed can continually survive under changing conditions, the straightforward approach would be to increase its utilization and attraction for production via mining breed germplasm characteristics.

• Asian-Australasian Journal of Animal Sciences
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• 제32권5호
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• pp.691-700
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• 2019

Objective: This study was conducted to assess increasing doses of phytase added to broiler diets formulated with different levels of available phosphorus (avP), calcium (Ca), and sodium (Na), and the respective effects on performance parameters, quantitative carcass characteristics, ash and phosphorus deposition in tibia and weight of organs. Methods: Three different matrices were assumed for phytase with the following nutritional values: matrix A (MT A): 0.165% Ca, 0.150% avP, and 0.035% Na; matrix B (MT B): 0.215% Ca, 0.195% avP, and 0.045% Na; matrix C (MT C): 0.245% Ca, 0.225% avP, and 0.053% Na. There were six different diets: No phytase (formulated to meet the nutritional requirements); phytase 500 FTU/kg+MT A; phytase 1,000 FTU/kg+MT A; phytase 1,500 FTU/kg+MT A; phytase 1,000 FTU/kg+MT B and phytase 1,500 FTU/kg+MT C. Results: There was no significant phytase influence on performance, quantitative carcass characteristics, ash and phosphorus deposition in tibia and weight of the organ throughout the study period, however, it was possible to observe a tendency of improvement in body weight corrected feed conversion for broilers fed the phytase 1,500+MT C diet, where potentially these birds were more efficient on utilize phytic phosphorus and other nutrients bounded to phytate molecule, translating into improvement in performance, and there was also a non significant numerical improvement in body weight corrected feed conversion of broilers fed this diet. Conclusion: Broilers fed with diets formulated with different levels of avP, Ca, and Na and increasing doses of phytase have shown no change on performance, quantitative carcass characteristics, ash and phosphorus deposition in tibia and weight of organs.

• Advances in nano research
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• 제10권2호
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• pp.115-128
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• 2021

In this article, free vibration behavior of electro-magneto-thermo sandwich Timoshenko beam made of porous core and Graphene Platelet Reinforced Composite (GPLRC) in a thermal environment is investigated. The governing equations of motion are derived by using the modified strain gradient theory for micro structures and Hamilton's principle. The magneto electro are under linear function along the thickness that contains magnetic and electric constant potentials and a cosine function. The effects of material length scale parameters, temperature change, various distributions of porous, different distributions of graphene platelets and thickness ratio on the natural frequency of Timoshenko beam are analyzed. The results show that an increase in aspect ratio, the temperature change, and the thickness of GPL leads to reduce the natural frequency; while vice versa for porous coefficient, volume fractions and length of GPL. Moreover, the effect of different size-dependent theories such as CT, MCST and MSGT on the natural frequency is investigated. It reveals that MSGT and CT have most and lowest values of natural frequency, respectively, because MSGT leads to increase the stiffness of micro Timoshenko sandwich beam by considering three material length scale parameters. It is seen that by increasing porosity coefficient, the natural frequency increases because both stiffness and mass matrices decreases, but the effect of reduction of mass matrix is more than stiffness matrix. Considering the piezo magneto-electric layers lead to enhance the stiffness of a micro beam, thus the natural frequency increases. It can be seen that with increasing of the value of WGPL, the stiffness of microbeam increases. As a result, the value of natural frequency enhances. It is shown that in hc/h = 0.7, the natural frequency for WGPL = 0.05 is 8% and 14% less than its for WGPL = 0.06 and WGPL = 0.07, respectively. The results show that with an increment in the length and width of GPLs, the natural frequency increases because the stiffness of micro structures enhances and vice versa for thickness of GPLs. It can be seen that the natural frequency for aGPL = 25 ㎛ and hc/h = 0.6 is 0.3% and 1% more than the one for aGPL = 5 ㎛ and aGPL = 1 ㎛, respectively.