• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.404-410
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• 2017

An analytical method for determination of propylene glycol alginate (PGA) in food products was developed by HPLC-size-exclusion chromatography. The GF-7M HQ column and LT-ELSD detector were determined by considering the instrumental analysis conditions for PGA analysis. The pretreatment method for the analysis of PGA was suitable for 3 hr extraction at $20^{\circ}C$ and 150 rpm according to the extraction temperature. Linearity ($R^2$) for the analysis of PGA was 0.9873 at calibration curve range of 300, 500, 700, 1,000, and 1,500 mg/kg (5 points). The limit of detection and limit of quantification of PGA on HPLC system was 171.43 and 519.50 mg/kg, respectively. The accuracy and coefficient of variation obtained by size-exclusion chromatography were 86.1~110.4% and 4.1~13.5%, respectively. By applying the HPLC-size-exclusion chromatography system, it was possible to analyze the contents of PGA in 134 different types of food products.

• Asia Marketing Journal
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• v.21 no.1
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• pp.45-64
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• 2019

A great deal of research has explored individuals' attempts to simplify choices by constructing a consideration set. This research aims to investigate which construction strategy, either inclusion or exclusion, is more likely to be adopted and how the adoption of a particular construction strategy can affect consideration set size while identifying the moderating role of chronic indecisiveness in the construction process. The findings of Study 1 indicate that individuals are more likely to adopt an inclusion strategy to reduce a consideration set to a more manageable size, and that an exclusion strategy results in a larger consideration set. In Study 2, the findings reveal that high-indecisiveness individuals are less likely than low-indecisiveness individuals to select an inclusion strategy, but that high-indecisiveness individuals adopting an inclusion strategy are able to reduce the number of alternatives in a consideration set to a manageable size on par with the size of a consideration set formed by low-indecisiveness individuals without elevating the level of perceived difficulty. The current research contributes to the stream of research on consideration set construction and indecisiveness, and offers useful practical implications for overcoming indecisiveness. Limitations and avenues for further research are also discussed.

• Journal of Soil and Groundwater Environment
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• v.9 no.3
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• pp.12-19
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• 2004

Binding mechanisms of polycyclic aromatic hydrocarbons (PAHs) with a purified Aldrich humic acid (PAHA) and its ultrafiltration (UF) size fractions were investigated. Organic carbon normalized binding coefficient ($K_oc$) values were estimated by both a conventional Stern-Volmer fluorescence quenching technique and a modified fluorescence quenching method. Pyrene $K_oc$ values depended on PAHA concentration as well as freely dissolved pyrene concentration. Such nonlinear sorption-type behaviors suggested the existence of specific interactions. Smaller molecular size PAH (naphthalene) exhibited higher $K_oc$ value with medium-size PAHA UF fractions whereas larger size PAH (pyrene) had higher extent of binding with larger PAHA UF fractions. The inconsistent observation for naphthalene versus pyrene was well explained by size exclusion effect, one of the previously suggested specific mechanisms for PAH binding. In general, the extent of pyrene binding increased with lower pH likely due to the neutralization of acidic functional groups in HS and the subsequent increase in hydrophobic HS region. However, pyrene $K_oc$ results with a large UF fraction (>100K Da) corroborated the existence of the size exclusion effect as demonstrated by an increase in $K_oc$ values at a certain higher pH range. The size exclusion effect appears to be effective only for the specific conditions (HS size or pH) that render HS hole st겨ctures to fit a target PAH.

• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.33-37
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• 1990

A simple and rapid method, based on separation of a flying oil into monomeric, dimeric and oligomeric triglyceride by means of high performance size exclusion chromatography on Ultrastyragel column (500 A), is proposed for evaluation of the quality of used frying oil. The relative area of the monomeric triglyceride was decreased with frying time increase, however, the decrease rate was significantly reduced by treatment of a composited powder (porous rhyorite/citric acid 40/56/4). This measurement showed good linear relationship with change in polar component measurement. There were no significant differences between the slopes of regression lines in both treated and non-treated frying oil system for relationship between monomeric triglyceride and polar component. By this method, it was found that a frying oil habe to be discarded if the content monomeric triglyceride decreased to 71%, which was corresponed to 27% polar component.

• Analytical Science and Technology
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• v.8 no.4
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• pp.405-410
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• 1995

A study on elemental speciation of trace metals in lake water (Lake Biwa in Japan) has been carried out by a size exclusion chromatography (SEC) / inductively coupled plasma mass spectrometry (ICP-MS) system. Before analysis, the water sample was preconcentrated with a ultrafiltration technique, where the large molecules with molecular weight larger than 10,000 were concentrated. Then the preconcentrated water samples (500-1000 fold) were analyzed by a SEC/ICP-MS system. Most trace metals were found at the UV absorption peaks corresponding to the molecular weights of ca. 300,000 and 10,000-50,000, where trace metals were on-line detected by ICP-MS. The results suggest that many of trace metals exist as the large organic molecules-metal complexes in natural water.

• Proceedings of the Korean Society of Life Science Conference
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• 2002.09a
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• pp.9-17
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• 2002

Renaturation of Lysozyme by size exclusion chromatography(SEC) to improve yield as well as the initial and final protein concentration has been studied in detail, Although urea decreases the rate of proteins refolding, it can suppress protein aggregation to sustain pathway of correct refolding at high protein concentration, and there existed an optimum urea concentration in renaturation buffer. Lysozyme was successfully refolded from initial protein concentration of up to 100mg/m1 by SEC, the yield was more than 40%. And the refolding of Interferon-${\gamma}$ was further investigated.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.5
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• pp.345-349
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• 2000

To easily separate chitosanoligosaccharides by size exclusion, an coencapsulating technology of substrate and enzyme was developed. The membrane was composed of alginate and a divalent cation such as calcium. Chitosan and chitosanase were enveloped in this membrane and the product released to medium by size exclusion. The capsule was stabilized in a 2% acetic acid solution (pH 5.0) containing 0.145 M CaCO$_3$. The leakage of substrate caused by the agitation speed was controlled by increasing alginate and CaCO$_3$concentrations. The lower limit of the alginate concentration and the agitation speed were 0.5% and 49rpm, respectively. Membrane thickness and capsule diameter were 10$\mu\textrm{m}$ and 2.5mm, respectively. By TLC analysis, the composition of chitosanoligosaccharides were mainly 3-6 mers. The molecular weight distribution of the released oligosaccharides ranged from 262 to 3624 Da by GPC.

• Molecular & Cellular Toxicology
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• v.1 no.2
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• pp.87-91
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• 2005

Although 2D-PAGE has been widely used as the primary method for protein separation, difficulties in displaying proteins with an extreme values of isoelectric paint (pI), molecular size and hydrophobicity limit the technique. In addition, time consuming steps involving protein transfer and extraction from the gel-pieces can result in sample loss. Here, we describe a novel protein separation technique with capillary size-exclusion chromatography (CSEC) for rapid protein identification from human plasma. The method includes protein fractionation along with molecular size followed by in-solution tryptic digestion and peptide analysis through reversed phase liquid chromatography (RPLC) coupled to nanoflow electrospray-tandem mass spectrometry (ESI-MS/MS). Tryptic peptides are applied an a $100\;{\mu}m\;i.d.{\times}10mm$ length pre-column and then separated on a $75\;{\mu}m{\times}200mm$ analytical column at -100 nL/min flaw rate. Proteins were identified over the wide ranges of pI (3.7-12.3) when this technique was applied to the analysis of $1-2\;{\mu}L$ of human plasma. This gel-free system provides fast fractionation and may be considered a complementary technique to SDS-PAGE in proteomics.

• Bulletin of the Korean Chemical Society
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• v.16 no.7
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• pp.640-643
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• 1995

The internal standard method, which is widely used in chromatographic techniques, is applied to the size exclusion chromatography for the on-line determination of dn/dc value of the sample. This method is found to provide the dn/dc value with suitable accuracy in determining the absolute molecular weight and the molecular weight distribution of the polymers when a light scattering detector is used.

• Journal of Internet of Things and Convergence
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• v.9 no.1
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• pp.77-87
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• 2023

Applying various association rule mining algorithms to the network intrusion detection task involves two critical issues: too large size of generated rule set which is hard to be utilized for IoT systems and hardness of control of false negative/positive rates. In this research, we propose an association rule mining algorithm based on the newly defined measures called coverage and exclusion. Coverage shows how frequently a pattern is discovered among the transactions of a class and exclusion does how frequently a pattern is not discovered in the transactions of the other classes. We compare our algorithm experimentally with the Apriori algorithm which is the most famous algorithm using the public dataset called KDDcup99. Compared to Apriori, the proposed algorithm reduces the resulting rule set size by up to 93.2 percent while keeping accuracy completely. The proposed algorithm also controls perfectly the false negative/positive rates of the generated rules by parameters. Therefore, network analysts can effectively apply the proposed association rule mining to the network intrusion detection task by solving two issues.