• Development and Reproduction
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• v.25 no.2
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• pp.75-82
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• 2021

We studied steroid metabolites produced from red-spotted grouper ovarian follicles during maturation. Oocytes with 350-500 ㎛ diameter were in vitro incubated in the presence of [³H] 17α-hydroxyprogesterone as a precursor. Steroid metabolites were extracted from incubated media and oocytes. The extracts were separated and identified using thin layer chromatography, high performance liquid chromatography and gas chromatography-mass spectrometry. The identified metabolites were androstenedione (A₄), testosterone (T) and estrone (E₁). The metabolites of A₄ was dominant in all size of oocytes and it was the highest in 480 ㎛ diameter oocytes. The metabolites of two progestins, 17α,20β-dihydroxy-4-pregnen-3-one and 17α,20α-dihydroxy-4-pregnen-3-one were detected in the oocytes less than 480 ㎛ diameter although they were not identified definitely. In the oocytes of 480 ㎛ diameter, metabolite of progestin was the highest, and germinal vesicle (GV) was still in the middle of cytoplasm. In the oocytes of 500 ㎛ diameter, GV was began to migrate and the major metabolites were A₄ and E₁. The metabolite of E₁ was detected in all size of oocytes and it was higher than that of E₂. These results suggest that oocytes of 480 ㎛ diameter are the transitional stage involving steroidogenic shift to final oocyte maturation and potential function of E₁ during maturation process.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.5 no.1
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• pp.21-27
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• 2024

Harmful pet insects, if not controlled, can negatively affect people, plants and their surrounding environment. In Vietnam, all crops are regularly impacted by pest insects. In serious cases, crops can be totally destroyed by insect pests. Harmful insects that damage crops often grow fast and increase rapidly. Therefore, research on insects is crucial for managing pests, protecting crops, and forecasting pest situation in the following years. This study aimed to collect data regarding changes of pests on rice and corn as two main crops in four provinces in Red River Delta of Vietnam, including Thai Binh, Nam Dinh, Ha Nam, and Hung Yen, from 2018 to 2022. Primary data were collected from reports of government agencies and official statistics. Based on these data, this study evaluated changes of pest insects in five years, discussed reasons for such changes and response methods, and forecasted pest's behavior in the following years. Significant findings of this study include the fact that Vietnam has to face many difficulties to develop its agricultural sector. For insect management, an essential action is to do ground surveys to gather all related data including weather data, pesticide data, crop yield, and product quality. This information is meaningful for finding out causes of changes, understanding relationships between insects and surrounding factors, and predicting the situation in the following years.

• Korean Journal of Ecology and Environment
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• v.47 no.1
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• pp.32-40
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• 2014

This study was conducted to evaluate the growth response of economical six leafy vegetables that are crown daisy, pak-choi and four kinds of lettuce (Red leaf lettuce, Green leaf lettuce, Head lettuce, Romaine lettuce) by light treatment of LED in plant factory. The light treatments were composed of red, blue, red+farred, red+blue, red+blue+white LEDs, irradiation time ratio of the red and blue LED per minute (1 : 1, 2 : 1, 5 : 1, 10 : 1), and duty ratio of mixed light (100%, 99%, 97%). The following results were obtained in different LED light sources treatments: Shoot biomass and S/R ratio of romaine lettuce were the highest under mixed red+blue LEDs. S/R ratio of head lettuce was higher under mixed red+blue+white LEDs than red+blue LEDs. The others showed no difference in LED light treatment. Shoot biomass, total biomass and S/R ratio of green lettuce, head lettuce and pak-choi were highest in the higher red ratio (5 : 1) on irradiation time of red : blue LED ratios. By the different duty ratio (red+blue and red+blue+white LEDs), Under the mixed light of red+blue, shoot and root biomass of crown daisy and romaine lettuce were high in duty ratio of 100% and 99%, and S/R ratio was highest in all the 6 kinds in duty ratio of 97%. All the 6 kinds showed a fine growth state in low duty ratio (97%). Green lettuce, romaine lettuce and pak-choi showed relatively high shoot biomass and total biomass in low duty ratio of 97% under the mixed light of red+blue+white. S/R ratio of romaine lettuce and head lettuce were highest in the duty ratio of 97% with red+blue+white LEDs. Thus, we can cultivate stably without reference to external factors, if we use appropriate light sources and light quality in closed-type plant factory.

• The Korean Journal of Food And Nutrition
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• v.18 no.2
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• pp.146-154
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• 2005

We compared two kinds of red peppers, semi-dry red popper and hot air dry red pepper, and made two kinds of Kimchies with them for this study. The semi-dry red pepper is better to maintain natural color of raw red pepper, to keep hygenity and to protect its loss of the nutrition, than the hot air dry red pepper. The results are as follows: The content of vitamin C and ASTA color value in semi-dry red pepper powder were much higher than those in hot air dry red pepper The cell numbers of total bacteria in semi-dry red pepper powder were much lower than those in hot air dry red pepper. The changes in quality of the two Kimchies were evaluated by pH, acidity, total microbes, lactic acid bacteria cells count and sensory. The patterns of changes in pH, acidity, total microbes and lactic acid bacteria cells count of two kinds of samples were the same. But in case of sensory evaluation, Kimchi made with semi-dry red powder showed best sensory scores than of all in overall acceptability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.6
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• pp.713-720
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• 2017

${\beta}-Carotene$, vitamin E, and folate contents according to color and species of Capsicum annuum were investigated. In addition, four C. annuum species were cooked by using different methods (boiling, pan-cooking, pan-frying, deep-frying, steaming, roasting, and microwaving), and retention rates of ${\beta}-Carotene$, vitamin E, and folate affected by color and species were evaluated. Weight loss was observed in all paprika and pepper species using all cooking methods. ${\beta}-Carotene$ and folate contents of C. annuum samples were significantly different by color, species, and cooking method (P<0.05), whereas vitamin E contents were not significantly affected by species. ${\beta}-Carotene$, vitamin E, and folate contents (mg/100 g) of raw C. annuum showed ranges of 95.4 (green pepper)~2,441.1 (red pepper), 0.7 (green paprika)~4.2 (red paprika), and 6.2 (green pepper)~148.7 (red pepper). As a result, the highest ${\beta}-Carotene$, vitamin E, and folate contents were detected in deep fried red pepper, roasted red pepper, and boiled red pepper, respectively, among the cooked samples. Retention rates of C. annuum varied by cooking method, resulting in ranges of 77.3% (boiled red pepper)~356.4% (roasted green pepper) for ${\beta}-Carotene$, 2.0% (microwaved red pepper)~789.3% (deep-fried green paprika) for vitamin E, and 20.9% (microwaved red pepper)~445.1% (steamed green pepper) for folate. Over 75% retention rates were observed for ${\beta}-Carotene$, vitamin E, and folate in all samples except for red pepper. However, in red pepper, vitamin E and folate retentions were remarkably lowered by deep frying and micro-waving, resulting in rates of 2.0~32.1%. This study provides information on effective cooking methods for vitamin retention in C. annuum depending on color and species.

• Journal of Plant Biotechnology
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• v.31 no.3
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• pp.239-248
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• 2004

This experiment was carried out to confirm that phytochrome regulates anthocyanin bio-synthesis during cell suspension culture system of grape or not. In suspension culture of grape, maximum accumulation of anthocyanin was observed at the stationary phase under continuous white light condition. From mono-chromatic light interruption for 24h at the 4th or 7th day on the suspension cultured cells, the anthocyanin accumulation was highly enhanced at the light interruption at 7th day than 4th day under all monochromatic light treatment. However, the cell growth patterns were not affected by any light treatment. In the darkness, the anthocyanin synthesis was very low but remarkably increased by blue light or red light irradiation. However, the increase of anthocyanin accumulation by blue or red light was suppressed by far-red light in the suspension cells of grape. This suppression by far-red light on the anthocyanin synthesis also observed on the cells treated red or far-red light alternatively. These results implied that phytochrome regulation system may be involved in the anthocyanin biosynthesis of the suspension grape cells. By RNA expression analysis, chalcone synthase (CHS) gene was expressed highly by blue and red light but low by far-red light. The synergistic increase of CHS gene expression was also observed at the treatment of blue light followed by red for 24h. This result may explain the increase of anthocyanin accumulation in B/R treatment. Although the expression of phytochrome gene (PHYA or PHYB) was not highly increased by all light treatment (blue, red, and far-red light) the expression of both PHYA gene and PHYB gene was increased a little in cells treated red or far-red light. In grape suspension cells, the red light enhanced the anthocyanin synthesis, whereas the far-red light was suppressed. Although it was not confirmed whether or not phytochrome gene is activated in anthocyanin accumulating grape cells, we believed that anthocyanin biosynthesis in grape cells may be regulated under phytochrome signal transduction system.

• Korean Journal of Food Science and Technology
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• v.6 no.4
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• pp.193-198
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• 1974

The antioxidant activity of ground red pepper, ethyl alcohol extracts of ground red pepper peel and alcohol extracts plus organic acid was studied by using edible soybean oil as a substrate. All the substrates were stored in a dark place at $45.0{\pm}0.5^{\circ}C$ respectively. The results of the study were as follow: 1. Ground red pepper, black pepper and cassia exhibited slight antioxidant activity and there was no significant difference in antioxidant activity among them. 2. Although both ground red pepper peel and red pepper seed showed antioxidant activity, ground red pepper peel exhibited greater antioxidant activity than ground red pepper peel did. 3. Ethyl alcohol extracts of red pepper peel showed strong antioxidant activity, but the residue did not show the antioxidant activity. 4. The antioxidant activity of the ethyl alcohol extracts of red pepper peel increased in direct proportion to the concentration of the extracts. 5. In connection with the synergistic effect of organic acid to the ethyl alcohol extracts of red pepper peel, citric acid showed a very strong synergistic effect on the antioxidant activity of red pepper, while ascorbic acid showed a weak effect. On the other hand, phosphoric acid showed an accelerating effect on the oxidation of oils. 6. The maximum antioxidant activity of the ethyl alcohol of ground red pepper peel was observed at the citric acid concentration of 0.04%, when tested at various concentration of citric acid.

• Korean journal of food and cookery science
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• v.24 no.2
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• pp.236-242
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• 2008

In this study, sponge cakes were prepared with 3, 6, 9, 12, and 15% red ginseng marc powder. The samples and a control were then compared in terms of quality characteristics, including batter viscosity and specific gravity, moisture content, water activity, volume index, weight, color, textural characteristics, and sensory qualities, in order to determine the optimal ratio of red ginseng marc powder in the formulation. The batter samples containing 0, 12, and 15% red ginseng marc powder had significantly higher viscosity than the other samples. Specific gravity of batter was not significantly different among the batter samples. The control group presented significantly higher moisture content as compared to the samples containing red ginseng marc powder samples. Water activity, volume index, and weight of all samples were not significantly different among the samples. In terms of crust color, lightness, redness, and yellowness of the crust samples decreased as the level of red ginseng marc powder content increased. For the crumb color, lightness and yellowness decreased, and redness increased, with increasing red ginseng marc powder content. Hardness, cohesiveness, gumminess, and springiness were not significantly different among the samples; however, the red ginseng marc powder samples had significantly higher chewiness than the control group. In the sensory evaluation, as the content of red ginseng marc powder increased, scores for color, flavor, softness, overall acceptability, moistness, and egg-flavor decreased, while scores for red ginseng taste, bitterness, astringency, and off-flavor incresed. Overall, the 3 and 6% red ginseng marc powder samples obtained fairly good sensory scores. In conclusion, the results indicate that adding $3{\sim}6%$ red ginseng marc powder to sponge cake is optimal, providing good physiological properties as well as reasonably high overall consumer acceptability.

• Asian Journal of Turfgrass Science
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• v.13 no.2
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• pp.71-78
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• 1999

The influence of increasing livel (0.0, 0.05, 0.1, 0.2, 0.4, 0.6, 0.8, 1.2, 1.6, and 2.0%) fo NaCl on the germination of red fescue (Festuca rubra) 'Sea Breeze', tall fesce(Festucaarundinacea) 'Pixie', creeping red fescue (Festuca rubra ssp. rubra) 'Cindy', annual rye-grass (Lolium multiflorum) 'Permer Ⅱ', perennial ryegrass (Lolium perenne) 'Pennant', fairway wheatgrass(Agropyron cristatum), creeping bentgrass (Agrostis palustris) 'Penncross', and kentucky bluegrass (Poa pratensis) 'Nuglade' was investigated. Red fescue 'Sea Breeze', tall fescue 'Pixie', and creeping red fescue 'Cindy' had greater than 90% seed germination at NaCl concentrations of 0.2% or lower, while showing similar seeding shoot and root lengths and TAA50 values as the control. Creeping red fescue 'Cindy'gave at 0.6% or higher NaCl. Perennial ryegrass 'Pennant' and annual ryegrass 'Permer Ⅱ' showed more than 95% seed germination when NaCl concentrations were 0.4% and 0.8%, respectively. Fairway wheatgrass, creeping bentgrass 'Penncross' and Kentucky bluegrass 'Nugade' had showing similar germination percent, shoot and root lengths and T50 values as the control at NaCl concentrations of 0.1% or lower. In general, germination percent and the lengthes of seedling roots and shoots of all species tested decreased as NaCl concentrations iscreased. The T50 values became greater as NaCl concentration increased. Seed fermination in red fescue 'Sea Breeze', tall fescue 'Pixie',perennial ryegrass 'Pennant', and annual ryegrass 'Permer Ⅱ' was compoetely inhibited at 2.0% NaCl. Creeping red fescue 'Cindy' and fairway wheatgrass gardly germinated at 1.6% MaCl. Creeping bentgrass 'Penncross' and Dentucky bluegrass 'Nuglade' showed a complete inhibition of germination at 1.2% and 0.6% NaCl, respectively.

• Journal of KIISE:Information Networking
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• v.28 no.4
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• pp.517-526
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• 2001

In order to reduce the increasing packet loss rates caused by an exponential increase in network traffic, the IETF(Internet Engineering Task Force) is considering the deployment of active queue management techniques such as RED(Random Early Detection). While active queue management in routers and gateways can potentially reduce total packet loss rates in the Internet, this paper has demonstrated the inherent weakness of current techniques and shows that they are ineffective in preventing high loss rates. The inherent problem with these queue management algorithms is that they all use queue lengths as the indicator of the severity of congestion. In this paper, in order to solve this problem, a new active queue management algorithm called MRED(Modified Random Early Detection) is proposed. MRED computes the packet drop probability based on our heuristic method rather than the simple method used in RED. Using simulation, MRED is shown to perform better than existing queue management schemes. To analyze the performance, we also measure throughput of traffics under the FIFO control, and compared the performance with that of this MRED system.