• Journal of Wetlands Research
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• v.19 no.2
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• pp.223-229
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• 2017

This study analyzed the relationship between environmental factors and the temporal changes of the bird populations during the every January from 1999 to 2016 (18 years) in Donglim reservoir. 'Winter Waterbird Census of Korea' data by National Institute of Biological Resources were used for the bird population data, and principal component analysis and cluster analysis were used to analyze the changes of annual population. The average temperature of January and the average storage rate of the reservoir were used as environmental factors. According to the results of the study, the population changes in the study area can be explained by the increase and decrease of two water bird groups and a mountain bird group. The average temperature of the years when the population of water bird groups increased was more than $1.4^{\circ}C$ in comparison with the year when mountain birds increased. On the other hand, the influence of the water content was not clear. The visiting of Baikal Teal affected by temperature was a factor affecting the other group of water bird and a mountain bird group. The results of this study suggest that the temperature change affects the global spatial distribution of birds and the migration of large population species such as Baikal Teal affects species composition and populations of birds at local scale. Therefore, understanding of environmental changes at large scale and spatial distribution of species and flock contributes to understand the temporal variation of the bird population at regional or local scales.

• Journal of Korean Society of Rural Planning
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• v.15 no.4
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• pp.75-87
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• 2009

This paper tries to explore the local uniqueness and evolutionary characteristics of the spatial structure of the rural dwelling houses of China's Korean Ethnic. For this purpose, the paper selected 51 typical samples in each district, analyzing their ancestral home, building age, size, construction method, family composition etc. Moreover, the paper classified the pattern of the samples and analyzed the characteristic and evolutionary process of each pattern. Conclusions based on the analysis of the ancestral homes are as follows: 1.The house pattern of these China's Korean ethnics who are originally from the Hamkyung province is mainly jeongji- access type (A-type). A-type is mainly distributed along the Tumen River and Yalu River, in the Sino-Russian borders and the inland areas of Heilongjiang province. With the migration of the China's Korean ethnics, in Sino-Russian borders and the inland areas of Heilongjiang province, A-type with the 'badang' space, vestibule-access type (C-type) and living-centered type (D-type) appeared. 2. House patterns of Korean ethnics who are originally from the Pyongan province include three types: A-type, kitchen type (B-type) and C-type. A-type is mainly distributed along the Yalu River while B-type and C-type are mainly in the inland areas of these three Northeast provinces. With the decrease of population, the merger of rooms happened in A-type; while in the B-type and C-type, bathroom and storage came to exist in the north of the room. 3. The house pattern of Korean ethnics who are originally from the Gyeongsang province is mainly B-type, which is distributed in the inland areas of Heilongjiang and Jilin provinces. Besides, C-type and D-type also exist. They are in Jilin and Liaoning provinces. In the process of evolution, storage was set in the north part of the room or the window was cancelled in order to defend the coldness in Heilongjiang area, while in Jilin and Liaoning provinces, living room came into existence, which is gradually developing to D-type.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.8 no.2
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• pp.49-59
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• 2002

The main function of plastic materials in food packaging is to preserve a food for safe transportation and storage. The interactions between food and plastic materials in food packaging have become increasingly important for food quality and safety because monomer, low molecular weight components, or additives of plastic packaging materials can migrate into a food. The use of antioxidants in plastic materials can help protect the degradation of film itself and retard the oxidation of a packaged food containing lipid, through the migration of antioxidant from the packaging to a product via an evaporation / sorption mechanism. Nowadays, antioxidant (BHT) impregnated plastic materials are used for commercial food packaging application with the intention of achieving an extended shelf life of food in USA. Alpha tocopherol, as one of the most important free radical scavengers, has been well known in biological systems. Moreover, the potential use of alpha tocopherol as an additive for polymers used in the packaging industry may offer the most positive perception from both consumers and manufacturers. Alpha tocopherol has been used as an antioxidant for polyolefin resins fabricated to both bottles and film and has applications in the food packaging industry as a replacement for BHT. Today, alpha tocopherol offers an attractive choice for use as an antioxidant in polymers. This paper provides an overview of antioxidant effectiveness and applications for its use by the food packaging industry based on the evaporation-sorption mechanism of a packaging model product, where quality is associated with lipid oxidation. Important analytical techniques for predicting antioxidant interaction between the package system and product are discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.7
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• pp.1077-1086
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• 2020

Objective: We examined the localization and expression of H⁺ pumping vacuolar ATPase (V-ATPase) and cytokeratin 5 (KRT5) in the epididymis of pigs, expressed in clear and basal cells, respectively, during postnatal development. Methods: Epididymides were obtained from pigs at 1, 7, 21, 60, 120, and 180 days of age; we observed the localization and expression patterns of V-ATPase and KRT5 in the different regions of these organs, namely, the caput, corpus, and cauda. The differentiation of epididymal epithelial cells was determined by immunofluorescence labeling using cell-type-specific markers and observed using confocal microscopy. Results: At postnatal day 5 (PND5), the localization of clear cells commenced migration from the cauda toward the caput. Although at PND120, goblet-shaped clear cells were detected along the entire length of the epididymis, those labeled for V-ATPase had disappeared from the corpus to cauda and were maintained only in the caput epididymis in adult pigs. In contrast, whereas basal cells labeled for KRT5 were only present in the vas deferens at birth, they were detected in all regions of the epididymis at PND60. These cells were localized at the base of the epithelium; however, no basal cells characterized by luminally extending cell projections were observed in any of the adult epididymides examined. Conclusion: The differentiation of clear and basal cells progressively initiates in a retrograde manner from the cauda to the caput epididymis. The cell-type-specific distribution and localization of the epithelial cells play important roles in establishing a unique luminal environment for sperm maturation and storage in the pig epididymis.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.4
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• pp.313-321
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• 2023

Platycodon grandiflorus (P. grandiflorus) flower is a perennial plant belonging to the family Campanulaceae and has many excellent pharmacological effects, so it has been used as a medicinal ingredient since ancient times. In addition, anthocyanin is a purple or blue natural pigment contained in plant flowers and fruits, and is known as a powerful antioxidant. The purpose of this study was to confirm the dermatological functionality of P. grandiflorus flower extract and the value of the bluish anthocyanin contained in flowers as a cosmetic material as a natural pigment. Firstly, 50% ethanol and 80% ethanol were added to the P. grandiflorus flower and extracted under reflux for 4 h at 25, 60, and 80 ℃, and the pH of each treatment group was similar. Based on the anthocyanin content and chromaticity (E^*ab), 50% ethanol 60 ℃ extraction conditions showing the color development most similar to the natural color of the P. grandifloras flower were selected, and a sample was prepared by concentrating and lyophilizing. The analysis results showed that the total phenol, total flavonoid, and total anthocyanin contents were in the ranges of 23 ㎍/mL, 16 ㎍/mL, and 0.17 ㎍/mL, respectively. The P. grandiflorus flower extract suppressed the production of nitric oxide (NO) and interleukin-6 (IL-6) in lipopolysaccharide (LPS) induced RAW264.7 cells. Furthermore, the P. grandiflorus flower extract showed wound healing effects through the promotion of skin cell migration in TNF-α stimulated human keratinocytes. The stability of anthocyanin and extract color was studied during a storage period of 50 days at various temperatures (4 ℃, 25 ℃, and 45 ℃). Color values (L, a, and b) of the P. grandiflorus flower extract changed over 50 days, whereas the bluish-purple color of the extract was stabilized using 5% maltodextrin. These results suggest that P. grandiflorus flower extract may be useful as a natural cosmetic pigment.