• The Korean Journal of Ecology
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• v.4 no.3_4
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• pp.114-123
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• 1981

Diurnal acid fluctuations, stomatal resistance, and morphology and anatomy were investigated in leaves and stems P. oleracea L. growing under the natural environmental condition. A CAM-like pattern of acid fluctuation was exhibited not in leaves of the young purslane but in its stems. Defoliated stems showed a decreased in diurnal changes of total acidity as compared with normal stems. Excised stems stored in continuous darkness exhibited diurnal acid rhythms, and they showed light deacidifications for three days. Kranz-type arrangement was observed in leaves, but not in stems. Micrography of cross sections of stems showed cells with relatively large vaculoles and a few chloroplasts. The number of stomata was 3,275cm-2 in leaves, while the stomata could not be observed in stems. Stomatal resistance was high at night and low in daytime in leaves of the young purslane, and the range of its value was 5~40 sec.$\textrm{cm}^{-1}$. But stomatal resistance in leaves of the water-stressed plant was comparratively high in day time, and its value was 30 sec.$\textrm{cm}^{-1}$. The result of these studies showed the possibility that the stem of P.oleracea L. possesses CAM under certain stressed conditions.

• Development and Reproduction
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• v.12 no.2
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• pp.117-124
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• 2008

The efficient strategies to cope with unpredictable and/or harmful environmental changes have been developed by every organism in order to ensure its survival and continuity of it's own species. As a results, all living things on earth maintain dynamically internal stability via a process termed 'homeostasis' among physiological parameters despite of external environment changes. Stress is an emotional and physical response to threat homeostasis. Stress may have not only transient but rather permanent effect on the organism; recent evidence clearly show that prenatal stress could organize or imprint permanently physiological systems without any change in genetic codes, a process known as 'epigenetic programming'. In this review, a series of reproduction-associated events occurred in prenatally stressed male rats such as alteration in the structure of sexually dimorphic brain regions, modification of neurotransmitter metabolism, changes in reproductive endocrine status, and finally, disorders of sexual behavior will be introduced. The fetal brain is highly sensitive to prenatal programming and glucocorticoids in particular have powerful brain-programming properties. The chronic hyperactivation of fetal brain by maternal stress-induced glucocorticoid input will provide new program via increasing the neuroplasticities. This 'increased neuroplasticities' will be the basis for the 'increased phenotypic plasticities' rendering the organism's better adaptation to environmental challenges. In conclusion, organism who experienced 'harsh' environment in his fetal life seems to give up a certain portion of reproductive competence to make good chance of survival in his future life by epigenetic (re)programming.

• Journal of the Korea Concrete Institute
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• v.26 no.2
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• pp.219-227
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• 2014

The purpose of this study is to investigate water purification properties of porous concrete by using effective microorganisms through the long-term continuous flow test. To solve the problems such as desorption of conventional microorganisms, in this study, tertiary treatment of the effective microorganisms identified by 16S rDNA sequence analysis was adopted per each step in the manufacturing process of porous concrete. And concentration for optimum continuous flow test and operation conditions through basic experiments according to retention time were investigated. Based on the experimental results, the porous concrete applying effective microorganisms showed no toxicity on the biological water quality and exhibited excellent removal efficiency than normal porous concrete. Therefore, contaminated water quality would be improved by treatment performance investigation of contaminants through long-term continuous flow test. If problems are complemented during the experiment process, it is expected to be able to reduce the non-point pollution sources flowing into river.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.308-315
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• 2011

We investigated ${\alpha}$-amylase, ${\alpha}$-glucosidase and lipase inhibitory activity of extracts collected from wild plants in Gangwon-do. 90 wild plants were collected and their water and ethanol extracts were obtained. Results of measuring ${\alpha}$-amylase inhibitory activity indicated more than 80% of activity inhibition in 10 mg/mL concentration for ethanol extracts of three plants and water extracts of two plants. For ${\alpha}$-glucosidase inhibitory activity, ethanol extracts of thirteen plants and water extracts of three plants showed more than 80% of activity inhibition in 10 mg/mL concentration. In the experiment of inhibiting lipase activity, ethanol extracts of seven plants and water extracts of one plants showed above 80% of activity inhibition in 10 mg/mL concentration. These results suggest that the selected extracts could be potentially used as a resource of bioactive materials for health functional foods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.215-220
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• 2001

Biochemical responses of rice to the flooding stress with different water turbidities and flooding time were evaluated. About 20% decrease of soluble protein was occurred with flooding stress. The decreasing rate was higher as flooding time and higher turbidity increased. Especially, dramatic decrease of soluble protein content was observed after 36 hrs of flooding. No protein subunit change was found before and after flooding. However, subunit product of 53 Kd increased from the beginning of flooding and subunit of 28 Kd was increased 48 hrs and 54 hrs after flooding. Lipid peroxidation increased about 150% by flooding. There was no significant difference in lipid peroxidation between clear and sub-muddy water, However, the lipid peroxidation was increased up to 180% at 60hrs of flooding. The malondialdehyde content (MDA) was higher in muddy water at the beginning of flooding and increased about 190-200% 36 hrs after flooding. Catalase activity increased with increasing turbidity and flooding time. Forty eight hours of flooding time provided a criteria for dramatic increase of catalase activity. In general, increase of saturated fatty acids and decrease of unsaturated fatty acids occurred with flooding treatment. Among unsaturated fatty acids, monounsaturated increased and polyunsaturated decreased. Double bond index(DBI) decreased as flooding time was extended and turbidity increased.

• Korean Journal of Poultry Science
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• v.24 no.4
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• pp.193-198
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• 1997

This study was conducted to obtain the basic information for hatchery by-products as feed resources. Four kinds of by-products from a commercial hatchery, i. e., autoclaved day-old broiler or egg type chicks, dead embryos ＆ infertile eggs of both chicks were used for chemical composition and bioavailability test. Chemical compositions were obtained by AOAC (1990) method, and amino acid and energy bioavailabilities were determined by the method of Sibbald (1976). The crude protein contents of day-old chicks (60.27∼62.59) were higher than those of dead embryos ＆ infertile eggs (39.24∼40.09) , whereas the crude fat contents of all by-products were not different. The crude ash contents were higher in dead embryos ＆ infertile eggs (29.18∼34.49％) than in day-old chicks (6.50∼6.71％). The Ca contents of dead embryos ＆ infertile eggs (8.79∼10.82％) were higher than those of day-old chicks (1.29∼l.30％). The total amino acid contents, overall amino acid availabilities and ME contents were higher in day-old chicks than in dead embryos ＆ infertile eggs. It seems that the day-old chicks of egg strain can be used as a high protein - high energy feed resources and the dead embryos ＆ infertile eggs of broiler or egg type as a high protein-high calcium feed ingredients.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2002.11a
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• pp.100-102
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• 2002

This study was conducted to determine the effect of feeding betaine on egg production, lipid metabolism and osmoregulation in laying hens. Three hundred and sixty layers were fed corn-soy basal diet containing 16% CP, 2800 kcal/kg ME from 18 to weeks. Hens were provided with betaine 0, 300, 500 or 1200 ppm. Egg production, feed intake, egg weight and feed conversion were examined in every four weeks. Liver and egg betaine. serum cholesterol and neutal fat were measured at the mid experiment. Egg production was not statistically different among treatments from 18 to 26 weeks of age, but significantly increased for the rest of period in hens fed more than 600ppm betaine(P＜0.05). Betaine added treatments showed a tendency to increase feed intake. Feed conversion tended to improve from 26 to 33 weeks old in betaine supplemental groups. Egg qualify was not influenced by dietary supplemental betaine. Betaine supplementation seemed to increase in liver betaine. but not in egg betaine. Serum total cholesterol, triacylglycerol, abdominal fat content and ileal osmolality were not different. However, liver fat content was prone to decrease in betaine supplemental groups. The result of this experiment suggested that dietary supplemtal betaine can improve the egg production and decrease liver fat content.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2002.11a
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• pp.122-123
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• 2002

An experiment was conducted to investigate the effect of dietary supplemental protease on performance, blood components, organ weight and protein digestibility. Two hundred and fifty, one day old cobb x cobb male broiler chicks were assigned to 4 treatments with 4 replicates. Four levels of protease were supplemented with 0, 40, 80 and 160U. Weight gain, feed intake, feed conversion were weekly measured for 5 weeks. Blood components and organ weight were examined at the end of experiment. Metabolic feeding trial was carried out to investigate the protein digestibility for one week at five weeks of age. Basal diets contained 21.5, 19.0% CP and 3,100, 3,200kca1/kg ME for starter and finisher, respectively. Weight gain of chicks fed 80U protease was significantly higher than other treatments for starting period(P〈0.05). Feed conversion of chicks fed protease addition diets was improved as dietary protease increased. It showed significant difference between 80U and control groups(P〈0.05). Sera protein tended to be lowered in protease added groups. HDL-cholesterol was decreased at the maximum level of protease. However, organ weight and protein digestibility were not influenced significantly by dietary protease level. In conclusion, the present study demonstrated that protease addition in broiler diets improved the feed conversion.

• Korean Journal of Poultry Science
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• v.24 no.4
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• pp.185-191
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• 1997

In order to obtain the basic information needed to utilize poultry by-products as feed resources, the yielding ratio, chemical composition and nutrient bioavailability of 5 offal components such as autoclaved head, feet, viscera, blood and feathers were investigated. Yielding ratios of head, feet, viscera, blood and feathers were 2.93％ 4.78％, 10.98％, 3.91％ and 4.83％, respectively. The crude protein contents of feathers (86.71％) and blood (82.99％) were higher than those of viscera (64.67％), feet (58.76％) and head (49.51％) , Inversely, the crude fat contents of blood (6.96％) and feathers (2.96％) were lower than those of head (26.19％), viscera (23.96％) and feet (13.73％). The crude ash contents of feet (21.69％) and head (20.38％) were higher than those of other by-products (0.96∼8.62％). The macro-mineral contents of head and feet were higher than those of other components, and the iron content of blood was higher than the other by-products. The total amino acid contents of poultry by-products showed the same trend as the crude protein contents. In addition, the Iysine content of feathers was very low compared to its high protein content. The essential amino acid contents of feathers were poorer than those of other offal components. Among the 5 offal components, the feathers showed the poorest amino acid availabilities. The ME contents were highest in viscera, and head, blood, feathers and feet. in decreasing order.

• Investigative Magnetic Resonance Imaging
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• v.1 no.1
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• pp.86-93
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• 1997

Purpose: To assess the ability of in vivo H-1 MRS to determine the degree of malignancy and to characterize the histopathologic type of intracranial solid tumors. Materials and Methods: In vivo H-1 MR spectra of the pathologically-proven 81 intracranial soild tumors (low-grade glioma 17 cases, high-grade glioma 31 cases, lymphoma 9 cases, meningioma 8 cases, central neurocytoma 4 cases, medulloblastoma 3 cases, PNET 3 cases, metastasis 2 cases, others 4 cases) were analyzed. H-1 MR spectroscopy was performed on a 1.5T MR unit using PRESS sequence with a TR of 2000ms, a TE of 270 or 135ms and a voxel size of $2{\times}2{\times}2cm^3$ for all spectra. N-acetyl aspartate (NAA)/Creatine complex(Cr), Choline complex (Cho)/Cr, and lactate (Lac)/Cr ratios were measured on the peak heights of each resonance and compared among the different tumors. Results: All intracranial solid tumors demonstrated decreased NAA, elevated Cho and lactate, and variable Cr levels. All tumors showed increased Cho/Cr and Lac/Cr, whereas NAA/Cr level was decreased. Mean Cho/Cr and Lac/Cr ratios were significantly higher in high-grade gliomas than in low-grade gliomas. However, NAA/Cr ratio showed no significant difference between low-grade and high-grade gliomas. Very high Cho peaks were seen in lymphomas, meningiomas, medulloblastomas, and neurocytomas in addition to high-grade gliomas. Conclusion: H-1 MRS may be useful in differentiating between low-grade and high-grade gliomas, however cannot characterize the histologic types or subtypes of tumors.