• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.2
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• pp.74-87
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• 2016

Potato phenology, growth, and yield are projected to be highly affected by global warming in the future. The objective of this study was to examine the responses of potato growth and yield to environmental elements like temperature, solar radiation, and daylength. Planting date experiments under open field condition were conducted using three cultivars differing in maturity group (Irish Cobbler and Superior as early; Atlantic as mid-late maturing) at eight different planting dates. In addition, elevated temperature experiment was conducted in four plastic houses controlled to target temperatures of ambient temperature (AT), $AT+1.5^{\circ}C$, $AT+3^{\circ}C$, and $AT+5^{\circ}C$ using cv. Superior. Tuber initiation onset was found to be hastened curve-linearly with increasing temperature, showing optimum temperature around $22-24^{\circ}C$, while delayed by longer photoperiod and lower solar radiation in Superior and Atlantic. In the planting date experiments where the average temperature is near optimal and solar radiation, rainfall, pest, and disease are not limiting factor for tuber yield, the most important determinant was growth duration, which is limited by the beginning of rainy season in summer and frost in the late fall. Yield tended to increase along with delayed tuber initiation. Within the optimum temperature range ($17^{\circ}-22^{\circ}C$), larger diurnal range of temperature increased the tuber yield. In an elevated temperature treatment of $AT+5.0^{\circ}C$, plants failed to form tubers as affected by high temperature, low irradiance, and long daylength. Tuber number at early growth stage was reduced by higher temperature, resulting in the decrease of assimilates allocated to tuber and the reduction of average tuber weight. Stem growth was enhanced by elevated temperature at the expense of tuber growth. Consequently, tuber yield decreased with elevated temperature above ambient and drop to almost nil at $AT+5.0^{\circ}C$.

• Journal of Animal Science and Technology
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• v.45 no.1
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• pp.41-48
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• 2003

Two experiments were conducted to investigate the effect of dietary supplementation of yeast culture on the performance of broiler chicks and noxious gas emission in broiler houses. Two hundred forty and three hundred and twenty, one day old Cobb male broiler chicks in Expt 1 and Expt 2, respectively were alloted to four treatment levels of yeast culture (0, 0.1, 0.2, 0.4%). To each treatment, 60 birds were assigned in Expt 1 and 5 replicates of 16 birds each were assigned in Expt 2. Basal diets contained 21.5% and 19.0% CP, and 3,100kcal/kg ME for the starting and finishing periods, respectively. Ammonia and $CO_2$ gas emission were detected twice a day for seven days during the five week period of Expt 1. Weight gain, feed intake and feed efficiency were measured for five weeks in Expt 2. Intestinal microbes, blood cholesterol and ND antibody titer were examined at the end of Expt 2. In Expt 1, the concentration of $NH_3$ in the house of birds fed yeast culture tended to be lower than the control. It was significantly lower in the 0.4% yeast culture treatment than the control (P<0.05). $CO_2$ concentration was significantly lower in all yeast culture treatments regardless of its dietary supplemental level than the control (P<0.05). different from others. Feed efficiency (feed/gain), however, was significantly improved in all yeast culture treatments relative to that of the control for starting period (P<0.05) and that of 0.2% yeast culture treatment was significantly lower than those of the control and 0.4% for the overall period. Total number of E. coli in the ileum of birds fed yeast culture at 0.1 and 0.2% was significantly lower than those of the control and 0.4% in the ileum. The CFU of Lactobacillus spp. of birds fed yeast culture at 0.1% was higher in the cecum compared to other treatments (P<0.05). Total cholesterol level of chicks fed 0.1% yeast culture seemed to be lower compared to that of other treatments, whereas LDL-cholesterol level was significantly lower than those of the control and 0.4% treatment. ND antibody titer tended to be higher in the yeast culture treatments than the control, but was not significantly different. The results of these experiments indicated that 0.2% yeast culture may have a potential to reduce the noxious gas emission in broiler houses and maximize the performance of broiler chicks.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.619-624
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• 1996

An experiment was carried out to find out the effects of water foxtail on weed control and rice yield as well as on the reduction of nitrogen application in no tillage transplanted paddy field. Paddy field was dominated by water foxtail whose soil covering degree was adjusted from 8 to 6 by treatment of paraquat (70 l /10a of solution diluted by 1, 000 times). Thirty five-day old seedling was mechanically transplanted and reduced nitrogen, 80% of conventional application was applied at the paddy field. The higher failure in seedling stand was observed at higher degree of soil covering by water foxtail. The failure of seedling stand with covering degree of 8(no paraquat) was 37.4%, while that of covering degree of 6(paraquat-treated) was 12.3%. However, the seedling stand failure was completely recovered at covering degree of six at two weeks after transplanting. The mechanical transplanting made water foxtail in the paddy field fall on the ground whose panicle part was recovered from falling sometimes after transplanting and whole plant died with slow scenesence untill the late of June. But the water foxtail affected by paraquat produced the new panicle from uppernode of stem with dead leaves at early of June and it become die slowly untill the early of July. Though several rice field weeds were observed in the order of Echinochloa crusgallis, Cyperus serotinus, Lemma paucicostata during the active tillering stage of rice, the value of weed control due to the dominance of water foxtail was 77~78%. The death and subsequent decay of water foxtail during the active tillering stage of rice induced the soil reduction which again defect the growth of rice root. The more vigerous rice growth was observed in the plot dominated with water foxtails, than control plot. The yields of rice in the water foxtail (degree 6) plot was 629kg per l0a as brown rice, the same as that of control plot. In conclusion, the no-tillage transplanting with control of covering degree of water foxtail (to degree 6) was effective in reduction of input cost such as herbicide and nitrogen fertilizer, as well as weed control without reduction of rice yield.

• Analytical Science and Technology
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• v.8 no.3
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• pp.321-334
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• 1995

Basic studies for the effective extraction of ammonium pyrrolidine dithiocarbamate(APDC) complexes of Co(II), Ni(II) and Cu(II) into a solvent have been performed. The maximum distribution ratio was appeared (log D=1.3543) at pH 2.0 and the partition coefficient was 2.489 in the extraction of $4{\times}10^{-5}M$ APDC itself into chloroform. From the UV/visible spectra of metal-chelates in aqueous and organic solutions, the pH to form stable 1:2 metal-ligand complexes were Co(II):5.0, Ni(II):8.0 and Cu(II):8.0, respectively and only 1 minute was enough to be partitioned into the chloroform. Besides, the partition and extraction equilibria of the complexes were investigated by back-extracting $10.0{\mu}g/ml$ metal-chelates from the solvent into an aqueous solution beacuse of their slight solubilities in the aqueous solution. The distribution coefficients and extractabilities were as follows : at pH 6.5~8.5 of the aqueous solution, log D=2.834 : E(%)=99.9% for $Co(PDC)_2$, at pH 11, log D=5.699 E%=100 for $Ni( PDC)_2$, and at pH 6.0, log D=2.025 : E(%)=99.1% for $Cu(PDC)_2$. And the extraction and formation constants were log $K_{ex}=9.671$ : log ${\beta}_2=6.938$ for $Co(PDC)_2$, log $K_{ex}=9.646$ : log ${\beta}_2=7.071$ for $Ni( PDC)_2$, and log $K_{ex}=9.074$ : log ${\beta}_2=7.049$ for $Cu(PDC)_2$, respectively. From these results, an optimum extraction procedure can be constructed for the separative concentration of trace metallic ions, and the quantitative determination of them in advanced materials and environmental samples will be expected without any influence of sample matrixes.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.53-63
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• 2010

As one of the mucous components of Cheonggukjang, traditional fermented soybean paste, $\gamma$-PGA is a natural substance with diverse functions. In this paper, an in-vivo experiment has been performed using NC/Nga mice in order to find out the efficacy of $\gamma$-PGA in human atopic dermatitis. The NC/Nga mice with BMAC-induced atopic dermatitis were administered $\gamma$-PGA (PGA-HM) with 300 kDa and low-molecular $\gamma$-PGA (PGA-LM), respectively. As a result, a significant decrease in clinical skin severity score was detected in the group that was administered PGA-LM. In terms of serum IgE levels, a significant decline was observed in PGA-LM, compared to the control group. The serum IgG1 levels also decreased more in PGA-LM than in the control group. However, no significant difference was observed in both groups. To witness the induction of $CD4^+CD25^+foxp3^+$ Treg cells, mRNA was sampled from the back of PGA-HM- and PGA-LM-administered NC/Nga mice with atopic dermatitis. In terms of the production amount of foxp3 mRNA, which was measured in real-time PCR, the group that was administered PGA-LM was twice as high as the control group. According to a biopsy on the skin on the backs of the mice, the experimental group was also far lower than the control group in terms of epidermis thickness, mast cell infiltration and the number of $CCR3^+$ cells. Therefore, it has been confirmed that the atopic dermatitis symptoms decreased more in the PGA-LM-administered NC/Nga mice than the PGA-HM-administered group by facilitating $CD4^+CD25^+foxp3^+$ Treg cells and suppressing the activity of eosinophils and production of IgE and pro-inflammatory cytokines.

• Korean Journal of Agricultural Science
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• v.3 no.1
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• pp.77-84
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• 1976

The preservation efficiency, quality and utilization of silage from 3 species of pumpkins (Mammoth pumpkin, Queensland blue pumpkin, Korean pumpkin) without and with 10, and 20% wheat bran additive were studied in this experiment. Silages were analysised and tested the chemical composition, pH and quality of silages between at 40-60 days and egg performance were carried out with mammoth pumpkin silage without additive. The results were summaried as follows. 1. The losses of all silage ware lower and similar as about 15% at 6 monthes following after silage-making but all raw pumpkins were spoilaged during the winter storaging. 2. The moisture content of silages were higher as about 97% in mammoth pumpkin silage, 94% in Queensland pumpkin silage and 91% in Korean pumpkin silage without additive and all nutrient content of silage without and with additive were depended on its content of raw silage material of pumpkins and wheat bran. The contents of moisture and N-free extract were slightly decrease but not significantly difference during the silaging and other contents were not so much changed. 3. Good quality of silage were made from all pumpkins with and without additive. Organic acid contents were 2.09-2.93% of lactic acid, 0.68-1.71% of acetic acid and 0% of butyric acid and it was pH 3.8-4.0 in silages. 4. Feed intakes, egg production and quality of egg were showed good result in 5.0 and 7.5% silage feeding group as D.M. base for egg performance. (P<0.01) 5. It was concluded that good quality of silage were made from pumpkins with and without wheat bran additive and it was suggested that poor quality feedstuff may be improved it feeding value by extended palatability with pumpkin additive silage.

• Journal of Life Science
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• v.22 no.11
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• pp.1477-1486
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• 2012

This study was performed to determine the effect of onion peel extract using 70% ethanol and 95% ethanol on its anti-oxidation activity, small intestine length, and intestinal villi of high-fat fed mice. Five percent of each onion peel extract using 70% and 95% ethanol showed significant decrease of E. coli and Listeria monocytogenes. Total phenolic contents of onion peel extracts using 70% and 95% ethanol were $166.89{\pm}0.03$ mg/g and $160.89{\pm}0.13$ mg/g, respectively. In anti-oxidation activity, DPPH radical scavenging activity and SOD-like activity of onion peel extracts were higher at 100 ug/ml concentration. The obese mice were fed high-fat diets supplemented by 1, 3, and 5% of the onion peel extracts using 70% and 95% ethanol for 4 weeks. Body weight, feed intake, feed efficiency, small intestine weight, length, villi's length, and number of bacteria in intestine were determined. Body weight of mice fed 5% of onion extracts using both 70% and 95% ethanol was significantly lower than that of control (p<0.05). However, feed intake was increased in mice fed 5% of onion extracts at both fermented ethanol levels. Small intestine weight and length of mice showed no significant change with supplementation of the onion peel extracts. However, length of small intestine villi was significantly longer than that of control. Total bacteria counts of Cl. Perfringenes and E. coli in small intestine of the mice were significantly reduced by supplementation of 5% of onion extract using ethanol, while lactic acid bacteria were increased. These results suggest that 5% of onion peel extracts using ethanol at either 70% or 95% concentration have potential to be used as an additive for body weight control and enhanced gut health; however, more research on its effectiveness is needed.

• Journal of Life Science
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• v.26 no.10
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• pp.1207-1213
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• 2016

Schisandrae fructus (SF) and Mori folium (MF) have been used as traditional medicines for thousands of years in parts of Asia, including Korea, China, and Japan. Recent researches on SF and MF have documented a wide spectrum of therapeutic properties, including anti-microbial, anti-inflammatory, anti-oxidative, immunomodulatory and anti-angiogenesis effects. However, the toxicity and safety of SF and MF, and their mixture (medicinal herber mixture, MHMIX) were not confirmed. Therefore, this study was performed to evaluate the acute toxicity and safety of SF, MF and MHMIX. SF, MF and MHMIX were orally administered at a dose of 5,000 mg/kg in ICR mice. Animals were monitored for the mortality and changes in the body weight, clinical signs and gross observation during the 14 days after dosing, upon necropsy. We also measured parameters of organ weight, clinical chemistry, and hematology. No dead and no clinical signs were found during the experiment period after administration of a single oral dose of SF, MF and MHMIX. There were no adverse effects on clinical signs, body weight, or organ weight and no gross pathological findings in any treatment group. Therefore, LD50 value of SF, MF and MHMIX may be over 5,000 mg/kg and it may have no side toxic effect to ICR mice. The results on the single-dose toxicity of SF, MF and MHMIX indicate that it is not possible to reach oral dose levels related to death or dose levels with any harmful side effects.

• Tuberculosis and Respiratory Diseases
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• v.51 no.6
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• pp.570-578
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• 2001

Background: With cases of chronic obstructive pulmonary disease(COPD), weight loss and low body weight have been found to correlate with increased mortality and poor prognosis. Therefore, nutritional aspects are an important part of the treatment in cases of COPD. In Korea, there is only limited data available for the changes of resting pulmonary function in relation to nutritional status. This study was carried out to investigate the differences of resting pulmonary function in relation to the nutritional status of patients with COPD. Method : 83 stable patients, with moderate to severe COPD, were clinically assessed for their nutritional status and resting pulmonary function. The patients' nutritional status was evaluated by body weight and fat-free mass (FFM), which was assessed by bioelectrical impedance analysis. According to their nutritional status, the 83 patients were divided into two groups, designated as the depleted, and non-depleted, groups. Result : Of the 83 patients, 31% were characterized by body weight loss and depletion of FFM, whereas 28% had either weight loss or depleted FFM. In the depleted group, significantly lower peak expiratory flow rate(p<0.05) and Kco(p<0.01), but significantly higher airway resistance(Raw, p<0.05) were noted. There was no difference for the non-depleted group in forced expiratory volume at one second, residual volume, inspiratory vital capacity, or total lung capacity. Maximal inspiratory pressure($P_{Imax}$) was also significantly lower in the depleted group(p<0.05). Conclusion : We conclude, from our clinical studies, that nutritional depletion is significantly associated with the change in resting pulmonary function for patients with moderate to severe COPD.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1343-1348
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• 2006

This study was performed to investigate the effects of silk protein enzyme hydrolysates on blood glucose and serum lipid in db/db diabetic mice. Twelve week-old-male C57BL/KsJ db/db mice were divided into two groups: diabetic control group and 0.25% silk protein hydrolysates solution group, which were fed for 8 weeks. Body weight increased in the silk protein hydrolysates group compared with the diabetic control group. There were no differences in food and water intake between the diabetic control and the silk protein hydrolysates groups. The weight of liver increased in the silk protein hydrolysates group while that of kidney increased in the diabetic control group. The blood glucose level increased about 18.0% in the diabetic control group after 8 weeks while that in the silk protein hydrolysates group increased about 5.8%. Also, silk protein hydrolysates improved the glucose tolerance in C57BL/KsJ db/db mice. There was no difference in total cholesterol and non-HDL cholesterol concentration between the diabetic control and the silk protein hydrolysates group. Triglyceride concentration were lower in the silk protein hydrolysates group than in the diabetic control group (p<0.05) while HDL-cholesterol concentration were higher in the silk protein hydrolysates group than in the diabetic control group (p<0.05). This results suggest that administration of silk protein enzyme hydrolysates reduces significantly an increasing rate of 1]food glucose, decreases triglyceride, and increases HDL-cholesterol in C57BL/KsJ db/db mice.