• Journal of Animal Science and Technology
• /
• v.62 no.1
• /
• pp.84-93
• /
• 2020

An experiment was conducted to evaluate Pediococcus spp.-fermented chicken meat as a snack for dogs. The fermented or non-fermented snacks used in this study were prepared through the following process; meat mixtures containing 52.8% MDCM, 35.2% chicken breast meat (CBM) and 9.7% corn starch were inoculated with or without Pediococcus spp., incubated at 37℃ for 24 h and then sterilized at 121℃ for 20 min. During the 24-h fermentation, the pH of fermented chicken snack dropped rapidly with concomitant increase in number of lactic acid bacteria. The nutritional composition was not altered by fermentation. In vitro pepsin nitrogen digestibility was higher (p < 0.05) in the fermented snack compared with the non-fermented snack. Upon storage at room temperature for 14 days, bacteria grew slowly in fermented vs. non-fermented snack samples. In a palatability trial, dogs preferred non-fermented over fermented snack food. In 12-d-long feeding trial, fecal ammonia content was lowered, but fecal lactic acid content was increased in dogs fed the fermented vs. non-fermented snack food. Our study shows that the fermented MDCM-based snack exhibited good preservability upon storage, and improved in vitro nitrogen digestibility and fecal characteristics in dogs.

• KSBB Journal
• /
• v.14 no.4
• /
• pp.408-413
• /
• 1999

To separate mixtures analytically and preparatively by LC (Liquid Chormatography), the operating conditions of analytical chromatography should be determined. The HCI program was utilized to find the optimum operating condition accurately and rapidly, and to reduce the number of experiments. In an analytical chromatography, based on the resolution and analysis time, the experimental conditons of deoxyribonucleosides and phopholipids were fixed in terms of taxol was calculated, and the collection time was predicted for the mixture of 5'-IMP and 5'-GMP from the elution profile when and purity wer known.

• Asian Journal of Atmospheric Environment
• /
• v.6 no.4
• /
• pp.288-303
• /
• 2012

In this study, real time measurements of particle number size distribution in urban Gwangju, coastal Taean, and industrial Yeosu in Korea were conducted in 2008 to understand the occurrence of ultrafine particle (UFP) (<100 nm) events, the variation of its concentration among different sampling sites, and UFP formation pathways. Also, to investigate seasonal and long-term variation of the UFP number concentration, data were collected for the period of 5 years (2007, 2008, 2010, 2011, and 2012) in urban Gwangju. Photochemical and combustion events were found to be responsible for the formation of UFP in the urban Gwangju site, whereas only photochemical event led to the formation of UFP in the coastal Taean site. The highest UFP concentration was found in industrial Yeosu (the average UFP number fractions were 79, 59 and 58% in Yeosu, Gwangju, and Taean, respectively), suggesting that high amount of gas pollutants (e.g., $NO_2$, $SO_2$, and volatile organic carbon (VOC)) emitted from industries and their photochemical reaction contributed for the elevated UFP concentration in the industrial Yeosu site. The UFP fraction also showed a seasonal variation with the peak value in spring (61.5, 54.5, 50.5, and 40.7% in spring, fall, summer, and winter, respectively) at urban Gwangju. Annual average UFP number concentrations in urban Gwangju were $5.53{\times}10^3\;cm^{-3}$, $4.68{\times}10^3\;cm^{-3}$, $5.32{\times}10^3\;cm^{-3}$, $3.99{\times}10^3\;cm^{-3}$, and $2.16{\times}10^3\;cm^{-3}$ in the year 2007, 2008, 2010, 2011, and 2012, respectively. Comparison of the annual average UFP number concentration with urban sites in other countries showed that the UFP concentrations of the Korean sites were lower than those in other urban cities, probably due to lower source strength in the current site. TEM/EDS analysis for the size-selected UFPs showed that the UFPs were classified into various types having different chemical species. Carbonaceous particles were observed in both combustion (soot and organics) and photochemical events (sulfate and organics). In the photochemical event, an internal mixture of organic species and ammonium sulfate/bisulfate was identified. Also, internal mixtures of aged Na-rich and organic species, aged Ca-rich particles, and doughnut shaped K-containing particles with elemental composition of a strong C with minor O, S, and K-likely to be originated from biomass burning nearby agricultural area, were observed. In addition, fly ash particles were also observed in the combustion event, not in the photochemical event.

• Korean journal of food and cookery science
• /
• v.31 no.1
• /
• pp.1-8
• /
• 2015

Organic acids are known as natural sanitizers. We examined the sanitizing effects of five organic acids (acetic acid, propionic acid, citric acid, malic acid, and lactic acid) and their persistence on three pectinolytic yeast strains isolated from decayed citrus, and the persistence of their sanitizing effects was determined during storage at $4^{\circ}C$ and $16^{\circ}C$. The 7~8 log CFU/mL of the mixed three yeast mixture was exposed to various concentrations of each organic acid for 1 min. The yeast mixtures decreased under detection limit(1 log CFU/mL) in 1% of acetic acid, followed by in 3% of propionic acid with the reduction of 5 log CFU/mL. The citric acid, malic acid, and lactic acid decreased the number of yeasts under detection limit at 7.5%. When treated with deionized water and 1~5% of organic acids were treated on the surfaces of citrus contaminated by yeasts, total numbers of the yeasts decreased under detection limit(3 log CFU) at 5% of acetic acid and 4 log CFU/piece at 5% propionic acid compared with deionized water. When treated with acetic acid and propionic acid on the stem ends of the contaminated citrus, total numbers of the yeasts significantly decreased 0.5 log CFU/piece at 3% of both organic acids. During storage at $4^{\circ}C$ and $16^{\circ}C$ for 20 days, total number of yeasts significantly decreased at 2% acetic acid compared with deionized water. This study suggested that organic acids could be used to sanitize microbial contaminants from citrus for storage and transportation.

• The Korea Journal of Herbology
• /
• v.33 no.4
• /
• pp.43-51
• /
• 2018

Objectives : Pharbitidis Semen, the seeds of Ipomoea nil (L.) Roth or I. purpurea (L.) Roth, is well-known traditional herbal medicine in Korea. But it is often marketed as a different seed or mixtures of its closely related species. Thus, the present study aims to provide external and micromorphological characters and identification key by using stereoscope (ST) and scanning electron microscope (SEM) for discriminating authentic of Pharbitidis Semen. Methods : A discrimination on external morphological characteristics of sepals, fruits, seeds, and hilum, testa cell micromorphology in the original plants and its congeneric species was carried out using digital calipers, ST, and SEM. Results : Number of valves (degree of apex of each valve), number of seeds per locule, hairy in capsules and size, luster, density of hairy, hilum shape in seeds and shape of cell, anticlinal, periclinal wall in testa may have high discriminative value. The seeds of Ipomoea nil as an original plant of Pharbitidis Semen were distinguished from other species by the relative larger in size, ovoid-trigonous in shape, mostly flabellate or triangular to trapezoid in outline (c.s.), dull, and puberulent in surface and thicken anticlinal wall. Conclusions : On the basis of the results, an identification key of Pharbitidis Semen and closely related species is provided. Our observations suggest that the combination of morphological characters and other studied results could be helpful in the successfully identified authentic herbal medicines. Moreover, micromorphological characters using SEM could be useful for discriminating authentic medicines.

• The Korean Journal of Food And Nutrition
• /
• v.20 no.1
• /
• pp.20-26
• /
• 2007

The characteristics of sponge cake were investigated with various flour types and amounts of ginseng powder. Sponge cake made with medium flour in combination with 2 and 4% mixtures of ginseng powder was found to be optimal as a cake flour control, being unaffected by the addition of ginseng powder. The results of alveogram showed that increment of ginseng powder decreased over pressure(P), extensibility(L) and swelling index(G) value. Farinogram, consistency, water absorption, stability, time to breakdown and the farinograph quality number all decreased with increasing ginseng powder however, the longest development time was the medium flour with a 2% ginseng powder mixture. Water activities were not significantly affected by addition of ginseng powder, however the 2% ginseng powder mixture showed a slight decrease in water activity. Addition of ginseng powder caused an increase in darkness, as well as redness and yellowness. The results of the sensory test suggest that the 2% ginseng powder mixture was preferable for the cake flour control.

• Nuclear Engineering and Technology
• /
• v.46 no.1
• /
• pp.109-116
• /
• 2014

An electrical resistance tomography (ERT) technique combining the particle swarm optimization (PSO) algorithm with the Gauss-Newton method is applied to the visualization of two-phase flows. In the ERT, the electrical conductivity distribution, namely the conductivity values of pixels (numerical meshes) comprising the domain in the context of a numerical image reconstruction algorithm, is estimated with the known injected currents through the electrodes attached on the domain boundary and the measured potentials on those electrodes. In spite of many favorable characteristics of ERT such as no radiation, low cost, and high temporal resolution compared to other tomography techniques, one of the major drawbacks of ERT is low spatial resolution due to the inherent ill-posedness of conventional image reconstruction algorithms. In fact, the number of known data is much less than that of the unknowns (meshes). Recalling that binary mixtures like two-phase flows consist of only two substances with distinct electrical conductivities, this work adopts the PSO algorithm for mesh grouping to reduce the number of unknowns. In order to verify the enhanced performance of the proposed method, several numerical tests are performed. The comparison between the proposed algorithm and conventional Gauss-Newton method shows significant improvements in the quality of reconstructed images.

• Mycobiology
• /
• v.30 no.1
• /
• pp.31-36
• /
• 2002

Soil bacteria were screened for the ability to control cucumber anthracnose caused by Colletotrichum orbiculare through induced systemic resistance(ISR). Sixty-four bacterial strains having in vitro antifungal activity were used for selecting ISR-inducing strains in cucumber. Cucumber seeds(cv. Baeknokdadagi) were sown in potting mixtures incorporated with the soil bacteria, at a rate of ca. $10^8$ cells per gram of the mixture. Two week-old plants were then transplanted into the steam-sterilized soil. Three leaf-stage plants were inoculated with a conidial suspension($5{\times}10^5$ conidia/ml) of C. orbiculare. Diseased leaf area(%) and number of lesions per $cm^2$ leaf were evaluated on third leaves of the plants, $5{\sim}6$ days after inoculation. Among 64 strains tested, nine strains, GC-B19, GC-B35, GK-B18, MM-B22, PK-B14, RC-B41, RC-B64, RC-B65, and RC-B77 significantly(P=0.05) reduced anthracnose disease compared to the untreated control. In contrast, some bacterial strains promoted susceptibility of cucumber to the disease. From the repeated experiments using the nine bacterial strains, GC-B19, MM-B22, PK-B14, and RC-B65 significantly(P=0.05) reduced both diseased leaf area(%) and number of lesions per $cm^2$ leaf in at lease one experiment. These strains with control efficacy of $37{\sim}80%$ were determined to be effective ISR-inducing strains.

• Journal of the Korean Institute of Gas
• /
• v.24 no.3
• /
• pp.20-26
• /
• 2020

In this study, experimental study was conducted to examine the influence of explosion pressure and flame propagation velocity of methane-air mixtures due to the obstacles placed in the explosion space. We used the quantified parameter named barrier ratio in order to generalize the effect of explosion pressure and flame propagation velocity in the closed explosion space with obstacles. From experimental observations, the explosion pressure and flame propagation velocity regardless of the number of obstacles increased with barrier ratio. In the same methane concentration of 10% methane, the flame propagation velocity without obstacle (barrier ratio = 0) was 3.46 m/s but 24.24 m/s (increase about 7 times) with 3 obstacle and barrier ratio of 0.98. In the same barrier ratio, explosion pressure and flame propagation velocity increased sharply with increasing of the number of obstacles.

• Textile Coloration and Finishing
• /
• v.6 no.1
• /
• pp.62-70
• /
• 1994

Silk fibroin was dissolved in 9.3 M LiBr aqueous solution at 4$0^{\circ}C$ for 1 hour. The dissolved silk fibroin was regenerated by casting the dialyzed solution into the membrane. The freshly prepared silk fibroin membrane was soluble in water and was. mainly consisted of random coil conformation. By the treatments in saturated water vapor at 3$0^{\circ}C$ and in 75% ethanolic aqueous solution (V/V), the insoluble membranes were obtained and the structure and morphology of those were investigated for the structure by means of X-ray diffraction analysis, infrared spectroscopy, thermal analysis. Rheovibron and scanning electron micrograph. Silk II type crystals were obtained by treating amorphous silk fibroin membrane in the random coil conformtion with 75% ethanol solution(V/V). Crystallization to silk II type crystals occured even after a few minutes, and a large number of silk II type crystals were formed after 30 mins. On the other and, the membrane treated in saturated water vapor was composed of the mixtures of silk I and silk II type crystals. A large number of silk I and silk II type crystals were formed after 24 hours. The micro brownian motion in the amorphous regions of silk fibroin membrane started at about 175~185$^{\circ}C$. $\alpha$ dispersion appeared at about 20$0^{\circ}C$ in the amorphous membrane, and at about 22$0^{\circ}C$ in the crystalline membrane. The crystallization of random coil conformation to silkII type crystals occured at about 215$^{\circ}C$. The surface, bottom and cross-section of the membranes were observed by scanning electrom microscope. Fine forms alike spherulites appeared at the surface of crystalline membrane.