• The Korean Journal of Ecology
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• v.25 no.3 s.107
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• pp.163-170
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• 2002

In order to analyze the life cycle of A. artemisiifolia var. elatior dormancy and some environmental factors inducing germination of the seeds were examined. The results were as follows : Dormancy of fertile seeds was broken in part within a month after seed collection in case of adequate moisture and alternating temperature was also effective in breaking dormancy. The temperature range, which allow germination was $12^{\circ}C{\sim}32^{\circ}C$. Optimum temperature for germination was $24^{\circ}C$. The seed of A. artemisiifolia var. elatior was light-independent. The difference of storage period appeared to have no particular effect on the viability of seeds at any time during the 9-month storage period. In the increasing temperature(IT) regime, A. artemisiifolia var. elatior seeds started to germinate at $16^{\circ}C$, showing the higher temperature the greater germination rate : the final germination percentage was 99.34%. On the other hand, in the decresing temperature(DT) regime, seeds began to germinate at $20^{\circ}C$ with the 1.34% germination. An induced dormancy occurred at $12^{\circ}C$ making the 5.34% final germination in the DT regime. Low temperature was more effective to break dormancy than higher temperature. Seeds of A. artemisiifolia var. elatior seems to be germinated in mid to late autumn or germination delayed until following spring. The above results suggest these variation of germination response in diverse environmental factors seems to be a physiological strategy to maintain their existence and to reproduce in the extreme thermal variation.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.3
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• pp.181-194
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• 2002

Parasitism is a one-sided relationship between two organisms in which one benefits at the expense of the other. Parasitic dinoflagellates, particularly species of Amoebophrya, have long been thought to be a potential biological agent for controlling harmful algal bloom(HAB). Amoebophrya infections have been reported for over 40 species representing more than 24 dinoflagellate genera including a few toxic species. Parasitic dinoflagellates Amoebophrya spp. have a relatively simple life cycle consisting of an infective dispersal stage (dinospore), an intracellular growth stage(trophont), and an extracellular reproductive stage(vermiform). Biology of dinospores such as infectivity, survival, and ability to successfully infect host cells differs among dinoflagellate host-parasite systems. There are growing reports that Amoebophrya spp.(previously, collectively known as Amoebophrya ceratii) exhibit the strong host specificity and would be a species complex composed of several host-specific taxa, based on the marked differences in host-parasite biology, cross infection, and molecular genetic data. Dinoflagellates become reproductively incompetent and are eventually killed by the parasite once infected. During the infection cycle of the parasite, the infected host exhibits ecophysiologically different patterns from those of uninfected host in various ways. Photosynthetic performance in autotrophic dinoflagellates can be significantly altered following infection by parasitic dinoflagellate Amoebophrya, with the magnitude of the effects over the infection cycle of the parasite depending on the site of infection. Parasitism by the parasitic dinoflagellate Amoebophrya could have significant impacts on host behavior such as diel vertical migration. Parasitic dinoflagellates may not only stimulate rapid cycling of dissolved organic materials and/or trace metals but also would repackage the relatively large sized host biomass into a number of smaller dinospores, thereby leading to better retention of host's material and energy within the microbial loop. To better understand the roles of parasites in plankton ecology and harmful algal dynamics, further research on a variety of dinoflagellate host-parasite systems is needed.

• Korean Journal of Ecology and Environment
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• v.37 no.4 s.109
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• pp.436-447
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• 2004

Wetland plants have evolved specialized adaptations to survive in the low-oxygen conditions associated with prolonged flooding. The development of internal gas space by means of aerenchyma is crucial for wetland plants to transport $O_2$ from the atmosphere into the roots and rhizome. The formation of tissue with high porosity depends on the species and environmental condition, which can control the depth of root penetration and the duration of root tolerance in the flooded sediments. The oxygen in the internal gas space of plants can be delivered from the atmosphere to the root and rhizome by both passive molecular diffusion and convective throughflow. The release of $O_2$ from the roots supplies oxygen demand for root respiration, microbial respiration, and chemical oxidation processes and stimulates aerobic decomposition of organic matter. Another essential mechanism of wetland plants is downward water movement across the root zone induced by water uptake. Natural and constructed wetlands sediments have low hydraulic conductivity due to the relatively fine particle sizes in the litter layer and, therefore, negligible water movement. Under such condition, the water uptake by wetland plants creates a water potential difference in the rhizosphere which acts as a driving force to draw water and dissolved solutes into the sediments. A large number of anatomical, morphological and physiological studies have been conducted to investigate the specialized adaptations of wetland plants that enable them to tolerate water saturated environment and to support their biochemical activities. Despite this, there is little knowledge regarding how the combined effects of wetland plants influence the biogeochemistry of wetland sediments. A further investigation of how the Presence of plants and their growth cycle affects the biogeochemistry of sediments will be of particular importance to understand the role of wetland in the ecological environment.

• Journal of Life Science
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• v.18 no.11
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• pp.1532-1537
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• 2008

The purpose of this study was to investigate the effect of different arthroplasty designs on knee kinematic and lower limb muscular activation for up-stair and down-stair movement. 3-D video analysis of whole body and joint kinematics and EMG analysis of quadriceps and hamstrings were conducted. One-way ANOVAs were used for statistical analyses (p=0.05). The single-radius group exhibited more arthroplasty limb quadriceps EMG and hamstring coactivation EMG than the multi-radius group. Single-radius demonstrated more abduction angular displacement and reached peak abduction earlier than the multi-radius arthroplasty limb. The single- radius the percent body fat showed similar values in the Elderly, Single and Multi-radius group among the periods, however Control group was Lowered among the periods. Single-radius group limb also increased the quadriceps muscle activation level to produce more knee extension moment to compensate for the short quadriceps moment arm. Resting metabolic rate was significantly increased in control group in the period of LI. Energy expenditure was extremely increased in all groups except control group among the periods. We can say this is the exercise effects.

• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.475-482
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• 2006

The quality characteristics and functional properties of fermented soybean by lactic acid bacteria (FSB) were investigated and compared with those of soybean (control) and commercial cheonggukjang Powder (CGP). The crude protein, lipid, and fiber contents of FSB were similar to those in CGP. The vitamin $B_2$ content in FSB (1.4 mg%) was similar to the control (1.3 mg%) whereas it was remarkably low in the CGP (0.2 mg%). The bright yellow color of FSB determined by Hunter's colormeter was quite different from the dark reddish brown color of the CGP. The pH of FSB was the lowest and thee amino-nitrogen was 517.2 mg%, which was higher than that in CGP (468.1 mg%). Glutamic acid, aspartic acid and leucine were the most abundant amino acids. In particular, the increase in the glutamic acid level was noticeable in FSB. The fatty acid compositions of FSB and CGP were similar to the control. However, the sucrose and fructose levels were lower after fermentation but the glucose level was higher. The results of isoflavone analysis by HPLC showed that the levels of daidzein and genistein in FSB were as much as 48.33 and 52.82 mg%, respectively, which is higher than that found in CGP. The DPPH free radical scavenging effects of FSB and CGP were 1.8 times higher an those of the control. The fibrinolytic activity determined by the diameter of the lysed area on the fibrin plate was the most effective in FSB. In conclusion, it is believed that FSB has a similar or higher quality than CGP. Therefore, FSB is expected to be good functional food material.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.193-193
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• 2017

The black heart in potato is a physiological disorder that occurs when potatoes suffer from breathing problems. When storing potatoes at a low temperature around $0^{\circ}C$, there is a high possibility that the respiration rate of potato will rise and black heart will occur. Also, respiration can occur easily and briefly in a state where high temperature and ventilation is insufficient. Recently, as black heart has been occurred continuously and severely in South Korea, here we tried to identify the causes of black heart in potato and to develop the control strategy of this disorder. Firstly, we analyzed the influence on the black heart on the basis of preservation containers (breathable plastic box, burlap bag, paper box, sealed plastic box). After harvesting the potato which is cv. Superior, it preserved for 6 months under conditions of temperature $3.5^{\circ}C{\pm}0.2$ and humidity 85%, after then we surveyed the incidence of emergence rate, rate of weight loss and occurrence rate of black heart. Secondly, in order to investigate the time point of black heart initiation under the oxygen concentration condition of 1% or less, The potatoes were used for this experiment stored for 6 months in a aerated plastic box under conditions of temperature $3.5^{\circ}C{\pm}0.2$ and humidity 85% under sufficient oxygen condition. After stored for 6 month, those were stored at $15^{\circ}C$ and below 1% of oxygen for 25 days, and then the incidence of black heart was surveyed. Thirdly, to investigate the effects of the number of days after harvest on the occurrence of black heart, it was examined the occurrence of black heart stored on 40 days and 100 days after harvesting under sealed condition and vacuum condition. The temperature condition of potato storage was stored was at $4^{\circ}C$ and $25^{\circ}C$ in humidity 85%. As a result of investigating the occurrence of black heart depending on the storage containers, all of the potatoes stored in the sealed plastic box had been occurred black heart. However, black heart of the potatoes in the other treatments did not. Potato preserved under the condition of below 1% of oxygen was found to occur 32% black heart after 25 days of storage. The potatoes corresponding to the required number of days after harvesting were stored for 31 days and the black heart was examined on the occurred. As a result, the potatoes which were 40 days after the harvest did not have black heart under sealed condition and vacuum condition. But potatoes harvested 100 days after harvesting had a black heart incidence of 95.7% under sealed condition at $4^{\circ}C$. The potato placed in the vacuum condition and a sealed state at $25^{\circ}C$ was transformed into anaerobic respiration, the inner tissue of tuber collapsed. Therefore, it is considered that black heart is caused by the breathing trouble in the central part when the oxygen is almost consumed after the aerobic respiration which gradually consumes the oxygen. We conclude that the black heart occurred in the central part where exchange of oxygen and carbon dioxide is the slowest is sensitive to respiration disorder. It is thought that research to investigate black heart generation time according to storage conditions and post-harvest state of potatoes is further necessary.

• Journal of the Korean Society of Radiology
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• v.5 no.6
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• pp.335-341
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• 2011

This paper searched the affect of Water dropwort and Tumeric on radiation exposure. By experimenting 50 male mouse, ICR type 5 weeks old male 25~30g, 5 mouse was divided in to each group respectively. A : 3 Gy control group, B : 5 Gy control group, C : 3 Gy, FW, D : 5 Gy FW, E : 3 Gy LW, F : 5 Gy LW, G : 3 Gy FT, H : 5 Gy FT, I : 3 Gy LT, J : 5 Gy LT FW : Ate Water dropwort before the radiation exposure. FT : Ate Tumeric before the radiation exposure. LW : Ate Water dropwort after the radiation exposure. LT : Ate Tumeric after the radiation exposure. During the 7 day radiation, Control group (A, B) received physiological saline (500mg/kg/day) in oral administration, LW and LT group (E, F, I, J) respectively received Water dropwort or tumeric (500mg/kg/day) in oral administration after the radiation, FW and FT group (C, D, G, H) respectively received Water dropwort or tumeric (500mg/kg/day) in oral administration before the radiation. As a result, an average leukocyte rate on 5 mouse was 200K/${\mu}L$ on group A. 6.46K/${\mu}L$ on group C which was in normal rate range (1.8-10.7 K/${\mu}L$). An average leukocyte rate was 23.33K/${\mu}L$ on group G. which was not normal rate, but compare to 200K/${\mu}L$, it was closer to normal rate. An average lymphocyte rate was 118.87K/${\mu}L$ on Group A. 1.51K/${\mu}L$ on Group G. which was in normal lymphocyte rate range (0.9-9.3K/${\mu}L$). An average thrombocyte rate was 4000K/${\mu}L$ on Group A. 1107 K/${\mu}L$ on Group C. 2759.6 K/${\mu}L$ on Group G. which was in normal thrombocyte rate range (592-2972 K/${\mu}L$). From this result, it was found that when exposed to radiation, Water dropwort and Tumeric have defensive effect in a preventive level. Also from an animal experiment, it was found that blood corpuscle rate returns to a normal rate. Based on this experiment, diverse research on this field should be conducted.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.814-821
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• 2014

As a natural plant ingredients, glasswort (Salicornia herbacea L.) contains various physiological activities, mainly anti-oxidative and anti-diabetic activities. However, only a few studies have been carried out on its anti-adipogenic effect. This study investigated the anti-obesity effects of Salicornia herbacea L. on 3T3-L1 adipocytes. As adipogenesis of preadipocytes to adipocytes involves proliferation and differentiation of cells, we treated three concentrations (125, 250, and $500{\mu}g/mL$) of Salicornia herbacea L. water extracts (SLW) in both pre-processing and post-processing stages. When 3T3-L1 adipocytes were differentiated and dyed with Oil Red O, adipocytes size and the value of relative Oil Red O staining were reduced by all concentrations of SLW in post-processing stage. Following adipogenic differentiation, the concentration of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in the cell supernatant significantly increased upon treatment with $125{\mu}g/mL$ of SLW and further rose at concentrations of 250 and $500{\mu}g/mL$ during post-processing stage. There was no significant difference in glycerol production upon SLW treatment. Leptin production significantly decreased at all SLW concentrations during post-processing stage, whereas peroxisome proliferator activated receptor-${\gamma}$ (PPAR-${\gamma}$) and adiponectin secretions were significantly enhanced. Overall results showed that SLW might have an anti-adipogenic effect via enhancement of TNF-${\alpha}$ production, which causes dedifferentiation and inhibits lipid accumulations in adipocyte. Furthermore, SLW might prevent diabetes and cardiovascular disease, as it reduces leptin secretion and enhances production of both PPAR-${\gamma}$ and adiponectin. However, further research is needed to elucidate the exact mechanism and bioactive compounds of glasswort.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.9
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• pp.1239-1248
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• 2016

Pumpkin juice (PJ), corn silk tea (CT), and adzuki bean tea (AT) have long been used for treatment of obesity in Korea. This study investigated the efficacy of PJ, CT, AT, and their mixture (PCA) on alteration of body weight and antioxidant metabolism in high-fat diet (HFD)-induced obese rats. After being fed HFD for 4 weeks, SD rats were divided into six groups fed a normal diet (ND), HFD, HFD+PJ [250 mg/kg body weight (BW)], HFD+CT (250 mg/kg BW), HFD+AT (250 mg/kg BW), and HFD+PCA (PJ : CT : AT=1:1:1, 250 mg/kg BW) for another 9 weeks. HFD consumption resulted in total lipid, triglyceride, and total cholesterol accumulation in adipose tissue, which was reduced by administration of PJ, CT, AT, or PCA. The plasma oxygen radical absorbance capacity value and hepatic glutathione peroxidase activity significantly increased compared to the HFD group. The liver thiobarbituric acid reactive substances was significantly lower in the PCA group than the HFD group. HFD-induced DNA damage in hepatocytes, as measured by comet assay, decreased in the PJ, AT, and PCA-supplemented groups. The PCA group exerted a superior antigenotoxic effect compared to other treatments. PCA recovered the concentration of plasma adiponectin, which was reduced by HFD. Adipocyte surface area (%) was significantly higher in the HFD group than the ND group, significantly lower in the PJ and PCA groups than the HFD group, and not significantly different compared with the ND group. Based on the results, supplementation of PJ, CT, AT, and PCA exhibited lipid-lowering effects in adipocytes of HFD-induced obese rats. Furthermore, the PCA group exhibited superior antioxidant activity in all treated groups. This study suggests that a mixed beverage consisting of PJ, CT, and AT may be a significant source of natural antioxidants, which might be helpful in preventing obesity and progress of various oxidative stresses induced by HFD.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.3
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• pp.271-277
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• 2006

A mechanically pressed juice of Bokbunja (Rubus coreanus Miq.) extract was prepared using 70% ethanol solution. The extract was subjected to gamma-irradiation treatment (20 kGy) and investigated for its change of color and biological activities. Hunter $L^*$ values of the irradiated Bokbunja extract were increased in comparison with the non-irradiated extracts, and the $a^*\;and\;b^*$values decreased by the irradiation treatment. The content of the total phenolic compounds in the non-irradiated and irradiated extracts were 58.4 and 56.5 mg/g, respectively. The 1,1-diphenyl-2-picrylhydrazyl(DPPH) radical scavenging activities of non-irradiated and irradiated extracts at a 250 ppm level were 80% and 79%, respectively. Lipid oxidation was retarded by addition of Bokbunja powder. Nitrite scavenging activity was the highest in the Bokbunja powder at pH 1.2 and the effect was not changed by irradiation. The Bokbunja powder showed antimicrobial activity against Salmonella Typhimurium and Bacillus cereus. However, irradiation of Bokbunja did not affect any physiological functions (p>0.05). A Salmonella mutagenicity assay indicated that the irradiated Bokbunja extract did not show any mutagenicity. Therefore, Bokbunja extract could be used in various applications as a functional material, such as ingredients of food and cosmetic, compositions with functions.