• Applied Microscopy
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• v.20 no.2
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• pp.71-80
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• 1990

It was investigated the morphological changes of differentiating epidermal cells in chick embryos. Ectodermal cells at 3 days after incubation were cuboidal, their nuclei were large, and rough endoplasmic reticulum and mitochondria were distributed in the cytoplasm. At 5 days after incubation, there were periderm and one basal layer in epidermis. The cells of basal layer were columnar, their nuclei were round, and rough endoplasmic reticulum and free ribosomes were developed. Also, peridermal cells were flat, chromatins were partially condensed and glycogen particles were abundant. No periderm showed and cells of basal layer formed intermediate layer at 9 days after incubation. Basal cells of intermediate layer were cuboidal, neighboring cells were anchored by desmosomes and tonofibrils and free ribosomes were evenly scattered. At 15 days after incubation, stratum corneum and stratum germinativum were distinguished. In cells of stratum germinativum, tonofibrils, free ribosomes and desmosomes were well developed. And then, the shedding of stratum corneum were showed at 17 days after incubation and stratum corneum were well developed after hatching.

• Carbon letters
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• v.25
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• pp.78-83
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• 2018

Pyrolyzed fuel oil (PFO) and coal tar was blended in the feedstock to produce pitch via thermal reaction. The blended feedstock and produced pitch were characterized to investigate the effect of the blending ratio. In the feedstock analysis, coal tar exhibited a distinct distribution in its boiling point related to the number of aromatic rings and showed higher Conradson carbon residue and aromaticity values of 26.6% and 0.67%, respectively, compared with PFO. The pitch yield changed with the blending ratio, while the softening point of the produced pitch was determined by the PFO ratio in the blends. On the other hand, the carbon yield increased with increasing coal tar ratio in the blends. This phenomenon indicated that the formation of aliphatic bridges in PFO may occur during the thermal reaction, resulting in an increased softening point. In addition, it was confirmed that the molecular weight distribution of the produced pitch was associated with the predominant feedstock in the blend.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.12
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• pp.1653-1658
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• 2000

Insulin-like growth factor-I (IGF-I) mRNA levels in the eyes, heart, liver and breast muscle removed from dwarf egg-type, normal egg-type and normal meat-type chicken embryos at 7, 14 and 20 days of incubation were measured. There was no influence of chicken strain on IGF-I gene expression in the eyes and liver. The IGF-I gene expression in eyes increased significantly along with the incubation period. In the liver, IGF-I gene expression at 20 days of incubation was significantly higher than that at 14 days of incubation. In the muscle, the lowest value for IGF-I gene expression was observed in meat-type chicken embryos. Regression analysis revealed that IGF-I gene expression was significantly correlated to the weights of the eyes and liver, but not the muscle. We conclude that there is little influence of strain on tissue IGF-I gene expression in chicken embryos during incubation but that tissue development in chicken embryos is nevertheless at least partly regulated by the change in IGF-I gene expression.

• Journal of Electrochemical Science and Technology
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• v.3 no.1
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• pp.24-28
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• 2012

The electrocatalytic activities and surface roughness of indium-tin-oxide (ITO) electrodes have been investigated after thermal treatment at 100, 150, or $200^{\circ}C$ for 30 min, 2 h, or 8 h. To check electrocatalytic activities, the electrochemical behavior of four electroactive species (p-hydroquinone, $Ru(NH_3){_6}^{3+}$, ferrocenemethanol, and $Fe(CN){_6}^{4-}$) has been measured. The electron transfer rate for p-hydroquinone oxidation and ferrocenemethanol oxidation increases with increasing the incubation temperature and the incubation period of time, but the rate for $Ru(NH_3){_6}^{3+}$ is similar irrespective of the incubation temperature and period because $Ru(NH_3){_6}^{3+}$ undergoes a fast outer-sphere reaction. Overall, the electrocatalytic activities of ITO electrodes increase with increasing the incubation temperature and period. The surface roughness of ITO electrodes increases with increasing the incubation temperature, and the thermal treatment generates many towering pillars as high as several tens of nanometer.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.4
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• pp.369-375
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• 1991

A series of in vitro incubation studies with washed rumen bacteria were conducted to determine the influence of incubation time and concentrations of peptides, alanine, ammonia nitrogen and carbohydrate on the rate of peptide disappearance and on bacterial growth. Disappearance rate of tri-alanine (ala3) under various conditions was between 30.6 and $58.2mg\;hr^-$ per gram bacterial dry matter. Ala3 was removed from the incubation medium in an almost linear fashion as incubation time and ala3 concentration was increased. Washed rumen bacteria utilized ala3 faster than di-l-alanine (ala2) at all concentrations. Adding 9mM carbohydrate significantly increased ala3 disappearance, but level of ammonia nitrogen had no influence on ala3 disappearance. The presence of alanine in the medium significantly lowered ala3 utilization by rumen bacteria. Bacterial dry matter and nitrogen growth yield were not influenced by alanine and peptides when incubation medium already contained a sufficient level of ammonia nitrogen. Increased ammonia nitrogen in the presence of ala3 did not stimulate bacterial growth. Carbohydrate significantly increased bacterial dry matter and nitrogen growth as expected. Results indicate that the rate of peptide utilization by rumen bacteria may be altered by type and concentration of peptides, and energy supply, and this may be mediated through changes in numbers and type of bacteria.

• The Korea Journal of Herbology
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• v.26 no.1
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• pp.53-58
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• 2011

Objectives : The purpose of this study is to investigate effects of Scutellariae Radix Water Extract on hydrogen peroxide production in RAW 264.7 mouse macrophages. Methods : Scutellariae Radix produced from South Korea (SK) and Scutellariae Radix produced from China (SC) were extracted by hot water. Effects of SK and SC on hydrogen peroxide production in RAW 264.7 were measured by dihydrorhodamine 123 assay after 2, 4, 20, 24, 28, 44, and 48 h incubation at the concentrations of 10, 25, 50, and 100 ug/mL. Results : SK significantly increase hydrogen peroxide production in RAW 264.7 cells for 2, 4, 20, 24, 28, 44, and 48 h incubation at the concentrations of 10, 25, 50, and 100 ug/mL (P < 0.05). SC also significantly increase hydrogen peroxide production in RAW 264.7 cells for 4, 20, 24, 28, and 48 h incubation at the concentrations of 10, 25, 50, and 100 ug/mL (P < 0.05). For 2 h incubation, SC significantly increase hydrogen peroxide production in RAW 264.7 cells at the concentrations of 10, 25, and 100 ug/mL (P < 0.05). For 44 h incubation, SC significantly increase hydrogen peroxide production in RAW 264.7 cells at the concentrations of 10, 25, and 50 ug/mL (P < 0.05). Conclusions : These results suggest that Scutellariae Radix has the immune - enhancing property related with its increasement of hydrogen peroxide production in macrophages.

• Communications for Statistical Applications and Methods
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• v.21 no.6
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• pp.487-500
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• 2014

A new method to calculate the transmittable prevalence of an epidemic disease is proposed based on a back-calculation formula. We calculated the probabilities of reactivation and of parasitemia as well as transmittable prevalence (the number of persons with parasitemia in the incubation period) of malaria in South Korea using incidence of 12 years(2001-2012). For this computation, a new probability function of transmittable condition is obtained. The probability of reactivation is estimated by the least squares method for the back-calculated longterm incubation period. The probability of parasitemia is calculated by a convolution of the survival function of the short-term incubation function and the probability of reactivation. Transmittable prevalence is computed by a convolution of the infected numbers and the probabilities of transmission. Confidence intervals are calculated using the parametric bootstrap method. The method proposed is applicable to other epidemic diseases in other countries where incidence and a long incubation period are available. We found the estimated transmittable prevalence in South Korea was concentrated in the summer with 276 cases on a peak at the $31^{st}$ week and with about a 60% reduction in the peak from the naive prevalence. The statistics of transmittable prevalence can be used for malaria prevention programs and to select blood transfusion donors.

• Mycobiology
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• v.34 no.2
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• pp.83-91
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• 2006

Characteristic growth patterns of Cordyceps militaris isolates on various media, under varying light conditions and at varying incubation periods were examined. Light was found to be the most critical single factor in determining the density, texture, and pigmentation of the mycelial culture of the fungus. However, under the light condition, the degree of pigmentation and mycelial density were found to be affected by the incubation period and type of medium. Irrespective of the variations in medium type or incubation period, there was no pigmentation of the mycelium under dark condition. Radial growth of the mycelium was faster under dark incubation rather than under light incubation. Abundant mycelial density and darkest pigmentation of C. militaris isolates were produced in nutritionally rich media like SDAY, SMAY and CZYA, suggesting that these media may fulfill all the requirements for vegetative growth of the fungus. Growth characteristics of C. militaris isolates could be easily observed by the simple agar culture method, which would be useful to characterize the phenotypic characteristics of large number of pure cultures of the fungus under given conditions of growth factors such as medium, light and temperature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.1
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• pp.124-128
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• 2021

This study was conducted to evaluate the effects of incubation methods and transfer timings on the hatching rate of fertilized eggs of the river puffer Takifugu obscurus. Four incubation methods were tested, a) control (fertilized eggs attached to the glass plate), b) bottom (fertilized eggs spread on the bottom of the tank without any treatment), c) S-bottom (removing the stickiness of the fertilized eggs, and then spreading the eggs on the bottom of the tank), and d) incubator (removing the stickiness of the fertilized eggs, and then incubating the eggs in an incubator). Additionally, four transfer timings were tested: a) control (no transfer from the incubation tank), b) zygote (fertilized eggs transferred at the zygote stage), c) segmentation (fertilized eggs transferred at the segmentation stage), and d) pharygula (fertilized eggs transferred at the pharygula state). The results showed that the hatching rate of incubator was significantly higher than those of control, bottom, and glass (P<0.05). The results also showed that the hatching rates of control and pharygula were significantly higher than those of zygote and segmentation (P<0.05).

• The Korean Journal of Food And Nutrition
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• v.9 no.3
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• pp.336-340
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• 1996

Rhizopus japonicus had the highest chitosan productivity compared with the chitosan productivity among Rhizopus sp. strains. To increase the productivity of microbial chitosan from Rhizopus faponicus, production medium and incubation conditions were optimized. The composition of the medium and the incubation conditions were as follows : starch 2%, yeast extract 2.5%, KH2PO4 0.05%, MgSO4 0.01%, FeSO4 0.002%, MnSO4 0.002%, ZnSO4 0.002%, CaC12 0.002%, PH 5.5, incubation temperature medium compared with chitosan productivity.