• 한국수산과학회지
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• 제48권2호
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• pp.178-186
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• 2015

Protease inhibitors (PI) of trypsin and papain as target proteases from the roe of bastard halibut Paralichthys olivaceus were fractionated out using ammonium sulfate precipitation (A), DEAE 650M anion exchange chromatography (D), and Sephacryl S-300 gel filtration (S). The recovery percentages of the fractions with the strongest inhibitory activity for each fractionation method were 13% for the A4 fraction, 21.2% for the D3 fraction, and 21.3% for the S2 fraction, with specific inhibitory activities of the fractions toward trypsin and casein of 168, 139, and 218 U/mg, respectively, while no inhibition of papain was observed. The $IC_{50}$ for the trypsin-specific substrate $N{\alpha}$-benzoyl-$\small{L}$-arginine-p-nitroanilide (BAPNA) was 0.65, 1.55, 2.26, and 2.85 mg/mL for the A4, S2, A3, and D3 fractions, respectively. These results suggest that chromatographic fractionation methods (D and S) based on the molecular mass and charge of the protein were more effective at fractionating PI than was ammonium sulfate precipitation based on protein solubility, and that the bastard halibut roe extract acts as a serine protease inhibitor. Therefore, the PI fraction from fish roe might be useful for inhibiting proteases in foodstuffs, and could constitute an alternative food-grade inhibitor for the surimi industry.

• Fisheries and Aquatic Sciences
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• 제19권5호
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• pp.25.1-25.8
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• 2016

The fractionation of serine protease inhibitor (SPI) from fish roe extracts was carried out using polyethylene glycol-4000 (PEG4000) precipitation. The protease inhibitory activity of extracts and PEG fractions from Alaska pollock (AP), bastard halibut (BH), skipjack tuna (ST), and yellowfin tuna (YT) roes were determined against target proteases. All of the roe extracts showed inhibitory activity toward bromelain (BR), chymotrypsin (CH), trypsin (TR), papain-EDTA (PED), and alcalase (AL) as target proteases. PEG fractions, which have positive inhibitory activity and high recovery (%), were the PEG1 fraction (0-5 %, w/v) against cysteine proteases (BR and PA) and the PEG4 fraction (20-40 %, w/v) against serine proteases (CH and TR). The strongest specific inhibitory activity toward CH and TR of PEG4 fractions was AP (9278 and 1170 U/mg) followed by ST (6687 and 2064 U/mg), YT (3951 and 1536 U/mg), and BH (538 and 98 U/mg). The inhibitory activity of serine protease in extracts and PEG fractions from fish roe was stronger than that of cysteine protease toward common casein substrate. Therefore, SPI is mainly distributed in fish roe and PEG fractionation effectively isolated the SPI from fish roes.

• 한국응용과학기술학회지
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• 제31권3호
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• pp.387-393
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• 2014

본 연구는 날치 난소막에서 추출한 날치 난소막 추출물(Flying fish Roe Shell Extract, 이하 FRSE라 명함)의 물리화학적인 특성을 조사하기 위하여 수행되었다. 해양성 원료인 날치 난소막에서 FRSE를 제조하여 물리화학적인 특성을 분석하였다. 영양성분 조성을 분석한 결과 FRSE는 81.00%의 단백질과 9.12%의 회분, 그리고 4.48%의 수분으로 구성되어있는 것으로 나타났다. 아미노산 조성분석결과 FRSE는 콜라겐 펩타이드의 특징인 OH-proline과 glycine이 검출되었으며, 포도당과 지방 대사에 관여하는 glutamic acid와 aspartic acid 함량이 높게 검출되었다. 또한 열량분석 결과에서는 100g의 FRSE가 347 kcal의 열량을 지니고 있는 것으로 나타났다. FRSE의 분자량 분석 결과에서는 약 1,300 Da정도의 평균분자량 분포를 나타낸다는 것을 알 수 있었다.

• 한국식품영양과학회지
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• 제20권5호
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• pp.503-508
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• 1991

영암어란의 제조방버은 건조기간이 긴 자연건조법으로 제조조건에 따라서 품질이 다르고 저장중 산화, 변색 및 단백질의 열화가 일어나 품질이 저하하였다. 본연구는 좋은 품질의 영암어란을 제조하기 위한 조건들의 확립을 위하여 품속에 따른 구성아미노산 함량과 산가, 과산화물가, TBA가의 변화로 최적풍속을 찾고 특성곡선을 구하였다. 엄장농도 5%, 바르는 참기름량은 3.0g/day에서 양호한 품질을 유지하기 위한 최적풍속으로 60% RH와 $20^{\circ}C$에서 2m/sec로 확정하였다. 영암어란의 제조에서 전통건조 방법의 건조기간은 20일이었으나 본 실험의 2m/sec 풍속에서 7일로 단축되었으며 이때의 건조특성곡선은 항율건조기가 없었고 감율건조기만 있었다.

• 국제지역연구
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• 제12권2호
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• pp.149-173
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• 2008

본 연구에서는 연구개발투자와 기업가치 간의 실증분석을 실시하였다. 우선 기업의 연구개발비 투자가 실질적으로 기업가치의 향상에 이바지하고 있음을 유추해 볼 수 있었다. 이러한 결과는 비록 미국회계기준 상 대차대조표 상에 자산의 항목이 아닌 비용의 항목으로 계상되지만 비용 측면 보다는 자산의 성격에 더 가깝다는 기존 연구자들의 주장을 뒷받침하는 결과라고 볼 수 있었다. 둘째, 연구개발비 증가율과 기업가치 간에는 단기적으론 연구개발비의 비용계상으로 오도 가격이 발생하여 즉각적인 기업가치의 증대를 기대하기는 어려웠다. 그러나 장기적으론 투자자들에게 있어 지속적적인 연구개발비 투자의 증가는 투자자 유인요인으로 작용할 수 있음을 예측해 볼 수 있었다. 셋째, 자본효율중시경영을 근간으로 한 기업의 연구개발투자 지출이 ROE의 상승을 가져올 수 있었으며 투자자들은 ROE가 높은 기업에 대해 해당기업의 투자 안의 선택에 있어 기업을 신뢰할 수 있어 주식시장에서 투자자 유인요인으로 작용 할 수 있을 것으로 판단되었다. 마지막으로, 연구개발을 통한 신기술의 개발은 실질적으로 기업 경쟁우위의 증대로 이어질 수 있으며 비용절감, 생산성 향상을 가질 수 있어 결국 기업의 수익성 배양 및 기업가치의 향상 요인으로 작용할 수 있을 것으로 분석되었다.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제2권1호
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• pp.1-14
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• 2021

The study has been carried out with an objective to prepare Siberian roe deer habitat potential maps in South Korea based on three geographic information system-based models including frequency ratio (FR) as a bivariate statistical approach as well as convolutional neural network (CNN) and long short-term memory (LSTM) as machine learning algorithms. According to field observations, 741 locations were reported as roe deer's habitat preferences. The dataset were divided with a proportion of 70:30 for constructing models and validation purposes. Through FR model, a total of 10 influential factors were opted for the modelling process, namely altitude, valley depth, slope height, topographic position index (TPI), topographic wetness index (TWI), normalized difference water index, drainage density, road density, radar intensity, and morphological feature. The results of variable importance analysis determined that TPI, TWI, altitude and valley depth have higher impact on predicting. Furthermore, the area under the receiver operating characteristic (ROC) curve was applied to assess the prediction accuracies of three models. The results showed that all the models almost have similar performances, but LSTM model had relatively higher prediction ability in comparison to FR and CNN models with the accuracy of 76% and 73% during the training and validation process. The obtained map of LSTM model was categorized into five classes of potentiality including very low, low, moderate, high and very high with proportions of 19.70%, 19.81%, 19.31%, 19.86%, and 21.31%, respectively. The resultant potential maps may be valuable to monitor and preserve the Siberian roe deer habitats.

• Fisheries and Aquatic Sciences
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• 제25권7호
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• pp.390-402
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• 2022

In this study we investigate physical and chemical characteristics of immature and mature skipjack tuna (Katsuwonus pelamis) roes in fresh and dried forms. Fresh roes were studied for histological structure and also dried by three methods: hot air drying (HD), vacuum drying (VD) and freeze drying (FD). The obtained roe powders were analysed for proximate composition, color value, fatty acid composition, amino acid profile, equivalent umami concentration (EUC) and protein pattern. Unyolked oocytes were more common in immature roes, while fully yolked oocytes were more common in mature roes. All dried tuna roes contained high content of protein and lipid (69.31%-70.55% and 11.14%-16.02%, respectively). The powders obtained by FD provided the highest lightness value (L^*). The main fatty acid found in all roe powders was docosahexaenoic acid (DHA) (23.49%-27.02%). Glutamic acid, leucine, and aspartic acid were the three most abundant amino acids found in the powders (13.58-14.61, 8.06-8.42, and 7.81-8.39 g/100 g of protein, respectively). The mature roe powder obtained from HD provided the highest EUC value (73.09 g monosodium glutamate/100 g of samples). The protein band at molecular weight of 97 kDa (vitelline) represented the major protein. Therefore, dried tuna roe could be a functional ingredient source of protein and lipid rich in DHA and it also has potential to be used as taste enhancer with umami compound.

• 한국조리학회지
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• 제22권6호
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• pp.52-60
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• 2016

This study attempts to measure the financial performance of the food distribution company. In order to achieve the goal, this study have measured the ratios of ROE, ROA applying the DuPont analysis, which have been demonstrated with tables to show the change periodically. DuPont analysis is based on analysis of Return on Equity (ROE) & Return on Investment (ROI). The return on equity disaggregate performance into three components: Net Profit Margin, Total Asset Turnover, and the Equity Multiplier. The return on investment consists of Assets Turnover (Operating Income${\times}$Total Assets) and Profit Margin (EBIT${\times}$Operating Income). From the study it if found that Hyundae Green Food's Financial performance is high followed by Foodmerce and then Dongwon home food and Lotte Food. The four companies are significant at their level. In conclusion, ROE & ROI is the most comprehensive measure of profitability of a firm. It considers the operating and investing decisions can be made as well as the financing and their leverage-related decisions.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2005년도 추계 학술대회논문집
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• pp.145-150
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• 2005

Generally, Compressible Navier-Stokes codes are used to solve high mach number flows. But, Most of high mach number flows embrace low mach number flows. This phenomenon results in low convergence rate and non-physical solution in CFD analysis. So Many researchers developed preconditioning technique to solve these problems. This Study presents how to modify previous compressible N-S computer code with little changes of structure into preconditioned compressible N-S code applying Roe's Approximate Riemann Solver. And this study show developed preconditioning code is very well operated at all mach number flows.

• Asian Journal of Business Environment
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• 제6권1호
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• pp.5-12
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• 2016

Purpose - The purpose of this study is to investigate the effect of corporate governance practices such as (board size, board composition, CEO duality and audit committee) on the performance of selected Pakistani firms. Research design, data, and methodology - This study examines corporate governance structure by using the data of 80 non-financial firms listed on Karachi Stock Exchange Pakistan during 2010-2014. Hypotheses of the study were tested by using both descriptive and inferential statistics. Result - The findings indicate that board size and audit committee is positively related to the firm performance (ROA & ROE). In contrast, board composition and CEO duality are negatively related to the firm performance (ROA & ROE). As far as controlling variables is concerned, leverage is negative, whereas firm size is positively related to all measures of performance. Conclusions - Empirical findings concluded that corporate governance practices affect the firm performance. Therefore, it is suggested that managers should understand the governance mechanisms to work more efficiently in the firm.