• International Journal of Naval Architecture and Ocean Engineering
• /
• v.13 no.1
• /
• pp.367-378
• /
• 2021

This paper develops a dynamic regression model to quantify the contribution of key external factors to operational energy efficiency of ships. On this basis, kernel density estimation is applied to explore distribution patterns of fluctuations in operational performance. An empirical analysis based on these methods show that distribution of fluctuations in Energy Efficiency Operational Indicator (EEOI) is leptokurtic and fat tailed, rather than a normal one. Around 85% of fluctuations in EEOI can be jointly explained by capacity utilization and sailing speed, while the rest depend on other external factors largely beyond control. The variations in capacity utilization and sailing speed cannot be fully passed on to the energy efficiency performance of ships, due to complex interactions between various external factors. The application of the methods is demonstrated, showing a potential approach to develop a rating mechanism for use in the legally binding framework on operational energy efficiency of ships.

• The Korean Journal of Pharmacology
• /
• v.23 no.2
• /
• pp.101-111
• /
• 1987

We investigated the binding properties of $(^3H)$ QNB and $(^3H)$ NMS to mAchR to elucidate the characterstics of mAchR in rat brain by using two different preparations (homogemates & intact brain cell aggregates). The binding properties of both ligands demonstrated high affinity and saturability in both experiments, however $(^3H)$ QNB showed a significantly higher maximal binding capacity than tha ot $(^3H)$ NMS 1. In rat brain homogenates; Displacement of both lignands with several mAchR antagonists resulted in competition curves in accoradnce with the law of massaction for QNB, atropine & scopolamine in thie preparation, also a similar profile was found for the quaternary ammonium analogs of atropine & scopolamine (methyl atropine & methylscopolamine) when $(^3H)$ NMS was used to label the receptors in rat brain. But when these hydrophillic antagonists were used to displace $(^3H)$ QNB, they showed interaction with high- and low-affinity binding sites in brain homogenates. Pirenzepine, the nonclassical mAchR antagonist, was able to displace both ligands from binding sites in this preparation. 2. In intact rat brain cell aggregates; Intact bain cell aggregates were used to elucidate the binding characteristics of $(^3H)$ NMS to mAchR in rat. The magnitude of binding of this ligand was related linearly to the amount of cell protein in the binding assay with a high ratio of total to nonspecific binding. mAchR antagonists displaced specific $(^3H)$ NMS binding according to the law of mass-action, while it was possible to resolve displacement curves using mAchR agonist into high-& low-affinity component. 3. Our results indicate that more hydrophilic receptor ligand $(^3H)$ QNB, displacement experiments in both tissues demonstrated that the lipid solubility of a particulr mAchR ligand might play an important role in determining its profile of binding to the mAchR, and the concentrations of mAchR in rat brain are both on the cell surface (membrane-bound receptor) and in the intracelluar membrane (intermembrane-bound receptor). 4. The results are discussed in terms of the usefulness of dissociated intact rat brain cells in studying mAchR in central nervous system.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.15 no.4
• /
• pp.107-114
• /
• 2007

A study on the removal of heavy metals using alginic acid, a kind of polysaccharides, was performed. Alginic acid adsorbed 480 mg Pb/g dry mass at pH 4, which was about twice as high as uptake capacity of other biosorbents. Isothermal adsorption curve for lead ions was described by the Langmuir model equation and the experimental data well fitted to model equation. The adsorption of lead ions was an endothermic process since binding strength increased with temperature. The effect of alkali metal ions ($Ca^{2+}$ and $Mg^{2+}$) on lead sorption capacity was negligible and most adsorption process was completed in 30min. The uptake capacity of other metals such as, copper, mercury, strontium, and cesium ions using alginic acid was also investigated.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.23 no.5
• /
• pp.401-406
• /
• 1990

In order to assess fish meal as food protein source which contains heat denatured pro-tein, functional properties of fish meal protein to be treated with alkaline were examined. Ratio of fish meal to 0.2N NaOH solution for extract solvent which were 1:10 showed good results of extracted and recovered amount of fish meal protein. pH 4.5, solubility of protein treated with alkaline revealed the lowest value. Until concentrations of alkaline treated protein solution reached $0.7\%$, its emulsifying capacity steeply decreased. Emusifying capacity of alkali treated protein were higher value at pH 9.0 than pH 4.0 and 7.0, and also were higher quantity in 0.5M NaCl solution than that of 0.1M. Heating time of fish meal protein to be treated with alkaline reached until 30 mins, its fat binding capacity indicated little change and that of heating time 60 mins decreased. Gel forming concentrations of fish meal protein to be treated with alkali for 15 mins or less were $20\%$ but those of 30 and 60 mins were $25\%$. When treating time of fish meal protein with alkali solution reached till 20 mins, viscosity of alkali treated protein solution steeply decreased.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.5
• /
• pp.581-585
• /
• 2005

Five lactic acid bacteria (LAB) including 2 Lactobacillus strains isolated from Kimchi were evaluated to determine the binding ability to Caco-2 cells and $AFB_1$. LAB were divided into three different groups ; viable, heat-treated, and acid-treated cells. In the radioactive-labeling assay for bound cell counting, viable Lactobacillus Plantarum KCTC 3099 showed the higher adhesion to Caco-2 cells with the binding capacity of $39.2\%$, which was $149\%$ higher than Lactobacillus rhamnosus GG as a positive control. Leuconostoc mesenteroids KCTC 3100 showed the similar binding ability to L. rhamnosus GG. After 1 hour incubation at $37^{\circ}C$ with $AFB_1$, viable L. Planterum KTCC 3099 removed the toxin by $49.8\%$, which was similar level to L. rhamnosus GG. Both heat- and acid-treated groups showed high binding effect but acid-treated group was more effective for both Caco-2 cell binding and $AFB_1$ removal than the other. These results indicate that components of bacterial cell wall might be involved in tile binding to intestinal cells and toxins.

• Food Science and Biotechnology
• /
• v.18 no.4
• /
• pp.855-860
• /
• 2009

Physicochemical properties of starches isolated from 3 new potato cultivars developed by Potato Valley Ltd. were investigated and compared to those of starch isolated from 'Superior' being distributed prominently in Korea. Significant differences were observed in physicochemical properties such as granule size, amylose content, phosphorus content, water binding capacity, swelling power, solubility, and in vitro digestibility of starches from different potato cultivars. Thermal properties were evaluated using differential scanning calorimetry (DSC), and onset gelatinization temperatire ($T_o$), peak temperature ($T_p$), and enthalpies of gelatinization (${\triangle}H$) of different potato cultivars ranged as $58.0{\pm}0.3-61.7{\pm}0.4^{\circ}C,\;63.7{\pm}0.2-$ $66.5{\pm}0.0^{\circ}C$, and $15.6{\pm}0.5-17.0{\pm}0.3$ J/g, respectively. Pasting properties were evaluated using a rapid visco analyzer (RVA), and pasting temperature, peak viscosity, and final viscosity of different potato cultivars ranged as $65.0{\pm}0.1-68.9{\pm}0.1^{\circ}C$, $8,163.7{\pm}196.3-9,035.7{\pm}6.4$ cp, and $4,397.7{\pm}166.7-7,025.0{\pm}271.3$ cp, respectively. Especially, 'Gogu valley' starch showed the highest values in the amylose and phosphorus content among tested potato cultivars and higher water binding capacity, swelling power, and solubility than those of other tested starches. And it also showed high pasting temperature, peak viscosity, trough viscosity, and final viscosity as compared to other tested starches.

• Journal of Yeungnam Medical Science
• /
• v.5 no.2
• /
• pp.37-45
• /
• 1988

Phosphoinositide-specific phospholipase C(PI-PLC) is a second messenger of signal transducer on cell membrane. In the previous study, PLC of bovine brain has been purified three isozymes. In this paper, uterus and seminal vesicle have been purified. Two peaks of PI-PLC activity were resolved when bovine uterus and seminal vesicle proteins were chromatographed on a DEAE and phenyl TSK 5PW HPLC column. Each two peak was compared with PI-PLC I, IT and ill from bovine brain and we got the retension time on HPLC. The peak fractions with PLC activity were tested homogeneity with brain PLC monoclonal antibodies(Mab). Mab-labeled affigels were bounded in the range of 73.8%~97.5% with PLC I, IT and III. Homogeneity of fractions were revealed that DEAE F-1 and phenyl F-1-I were highest level of PLC III in uterus and seminal vesicle and DEAE F-2 and phenyl F-2-I were mixed PLC I and II.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.18 no.2
• /
• pp.195-198
• /
• 1989

The water binding capacity (WBC) of hoe plasma protein was investigated. The centrifugal condition for optimal separation of plasma from hog blood was fixed at 1400 g-force. The WBC of 5%-plasma-protein-solution eel increased rapidly between pH 6 and 7 but gradually after pH 7 at $85^{\circ}C$ for 30 min. The higher heating temperature demonstrated the higher WBC of 5%-plasma-protein-solution gel at pH 7 within short period of time. The WBC of 5%-plasma-protein-solution gel increased rapidly at the beginning of heating. The WBC per gram of plasma protein at pH 7 and $85^{\circ}C$ for 30 min decreased as protein concentration of the plasma solution increased.

• Preventive Nutrition and Food Science
• /
• v.20 no.1
• /
• pp.43-51
• /
• 2015

${\varepsilon}$-Polylysine (EPL) is used as a natural preservative in food. However, few studies have been conducted to assess the beneficial functions of dietary EPL. The purpose of this study was to elucidate the mechanism underlying the inhibition of neutral and acidic sterol absorption and hepatic enzyme activity-related fatty acid biosynthesis following EPL intake. EPL digest prepared using an in vitro digestion model had lower lipase activity and micellar lipid solubility and higher bile acid binding capacity than casein digest. Male Wistar rats were fed an AIN-93G diet containing 1% (wt/wt) EPL or L-lysine. After 4 weeks of feeding these diets, the marked decrease in serum and liver triacylglycerol contents by the EPL diet was partly attributed to increased fecal fatty acid excretion. The activities of hepatic acetyl-coenzyme A carboxylase and glucose-6-phosphate dehydrogenase, which are key enzymes of fatty acid biosynthesis, were enhanced in rats fed EPL diet. The increased fatty acid biosynthesis activity due to dietary EPL may be prevented by the enhancement of fecal fatty acid excretion. The hypocholesterolemic effect of EPL was mediated by increased fecal neutral and acidic sterol excretions due to the EPL digest suppressing micellar lipid solubility and high bile acid binding capacity. These results show that dietary EPL has beneficial effects that could help prevent lifestyle-related diseases such as hyperlipidemia and atherosclerosis.

• Korean Journal of Food Science and Technology
• /
• v.31 no.5
• /
• pp.1216-1220
• /
• 1999

The effects of low-temperature blanching on the physical properties of chestnut powder were studied. Chestnuts were blanched in water for 15, 30 and 60 min., each at three temperatures viz. $45^{\circ}C,\;55^{\circ}C$ and $65^{\circ}C$. The particle size of chestnut powder was prepared smaller than 60 mesh$(250\;{\mu}m)$. Higher blanching time and temperature increased water binding capacity(WBC) of chestnut powder. Water soluble index(WSI) was the highest for chestnuts blanched at $65^{\circ}C$ for 30 min. As with water binding capacity(WBC), swelling power of chestnut powder increased with increasing blanching time and temperature but solubility showed an reduction by increasing blanching temperature. In Brabender amylographic examination, peak viscosity of chestnut powder showed great change, but the gelatinization temperature showed no significant differences by blanching conditions.