• Journal of Bio-Environment Control
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• v.32 no.1
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• pp.64-71
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• 2023

Crassulacean acid metabolism (CAM) plants use surplus CO₂ generated by cooling and heating at night when ventilation is not needed in a greenhouse. Schlumbergera truncata 'Pink Dew' is a multi-flowering cactus that needs more phylloclades for high-quality production. This study examined photosynthetic characteristics by the phylloclade levels of S. truncata in a growth chamber and a greenhouse for use of night CO₂ enrichment. The CO₂ uptake rate of the S. truncata's top phylloclade in a growth chamber exhibited a C₃ pattern, and the second phylloclade exhibited a C₃-CAM pattern. The CO₂ uptake rate of the top phylloclade in a greenhouse showed a negative value both day and night, but those of the second phylloclade exhibited a CAM pattern. The stomatal conductance and water-use efficiency (WUE) of S. truncata at both the top and second phylloclades were higher in a growth chamber than in a greenhouse. The WUE of S. truncata in a growth chamber and a greenhouse was higher at the second phylloclade, which is a CAM pattern compared with those of the top phylloclade. The daily total net CO₂ uptake of S. truncata was higher in a growth chamber than in a greenhouse. The daily total net CO₂ uptake of S. truncata at the second phylloclade had the highest value of 155 mmol·m^-2·d^-1 in a growth chamber. The night total CO₂ uptake of S. truncate at the second phylloclade was 3-fold higher in a growth chamber than in a greenhouse. S. truncata's second phylloclade exhibited a CAM pattern that uptake CO₂ at night, and the second phylloclade, was more mature than the top phylloclade. A multi-flowering cactus S. truncata 'Pink Dew' efficiently uptake night surplus CO₂ in the proper environmental condition with matured phylloclade.

• The Korean Journal of Malacology
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• v.31 no.4
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• pp.263-266
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• 2015

This study was performed to determine the effect of water temperature condition on survival rate and growth of juvenile geoduck (Panopea japonica). Panopea japonica juveniles were bred for 6 weeks at 12, 15, 18, 21, 24 and $27^{\circ}C$ on incubator. Juveniles median lethal times (LT50) were 29 hours in $27^{\circ}C$, 14.5 day in $24^{\circ}C$, 37.4 day in $21^{\circ}C$. Survival rate of water temperature 12, 15 and $18^{\circ}C$ showed a high survival rate in 95.0%, 95.0% and 93.3% at 6 weeks. As a result of culturing for 6 weeks at 12, 15, 18, 21 and $24^{\circ}C$, a daily growth of shell length and total weight was 0.10 mm, 0.12 mm, 0.13 mm, 0.16 mm and 0.14 mm, and 2.21 mg, 2.65 mg, 2.84 mg, 3.13 mg and 2.93 mg. Juvenile shell length and total weight have significantly increased at $15-21^{\circ}C$. However, mortality rate has significantly increased at more than $21^{\circ}C$. As a result, appropriate water temperature for juveniles culturing considered $15-18^{\circ}C$.

• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.4
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• pp.59-68
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• 1992

A Study was made to improve soil and water temperature and mechanized farming for a wetted paddy under the influence of artesian groundwater located at Samcheon-Dong, Chuncheon City, Kangweon Province. Half perforated PVC drainage pipes were installed in the test paddy to observe temperature change of water and soil. The temperature of the water in the paddy and soil itself raised significantly after the installation of the half perforated PVC pipes. A subsequent improvement of growth and yield of rice on the paddy was achieved. Harvesting operation was also improved with firm ground condition so that cutting and threshing could be done simultaneously within the paddy plot. Following results were obtained from the study. 1.Temperature of the water in a paddy under the influence of artesian groundwater was not changed notably although air temperature was fluctuated during the crop period. Soil temperature was mostly affected by the artesian groundwater. However, the half perforated PVC pipe drainage system made it possible to raise temperature of water and soil remarkably up to the level of optimum farming. 2.Total precipitation was 534.Omm during the crop period of the paddy for 118 days from May 26 to September 20 in 1992. Due to heavy rainfalls of 105.6mm and 109.8mm occurred on August 7 and August 27.1992, respectively, the rate of the artesian groundwater increased to 35 litter per minute with two to three days of time lag. 3.Average rate of the artesian groundwater was 28 litter per minute from the one year of observation. The rate varied by 0.7 to 1.3 times of average during the observation period. Peak rate of the artesian groundwater decreased to 14.5 litter per minute when daily precipitation maintained at the amount of 20 to 30mm for a long time period. Contrarily, it showed a tendency to increase to 35 to 40 litter per minute when heavier precipitation of 50 to l00mm occurred in a short period of three to five days. 4.Growth and yield of Yemyung variety of rice planted on the paddy that was facilitated with a drainage system with half perforated PVC pipes were confirmed at a normal level, while paddy without this perporated drainage system showed abnormal growth with low yield.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.2
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• pp.151-155
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• 2020

This study was conducted to determine the effects of the selection of an appropriate sowing method in on ginseng growth, and the results are as follows. SAS (semi-automatic sower), commonly used by direct seeding farms, provides fast operation speed but results in high labor cost, while (Hooper Seeder Sowing) offers fast operation speed and high germination rate, but leads to increased laborer's fatigue. Daily working area per sower was 6,611 ㎡ for a motor type, and the operation time to sow 3,305 ㎡ was 15 hours for broadcast planting, and 8 hours for SAS. The germination rate of 1-year-old ginseng according to direct seeding was 69.1% for the treatment plot under broadcast planting, followed by 66.4% and 67.3% for manual sower and hoop sower, respectively, and the germination rate of SAS was the lowest at 64.2%. In addition, there were no differences in shoot and root growth of 1-year-old ginseng among the sowing methods. Therefore, the sowing method can be chosen depending on the economic size of ginseng farmers. That broadcast sowing (BS) is appropriate for small scale farmers, while motor-driven seeder sowing (MDS) for direct seeding is more suitable for large scale farmers.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.6
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• pp.853-860
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• 2008

This experiment was conducted to study the effects of chromium (Cr), dietary crude protein (CP) level and potential interactions between these two factors on growth rate and carcass response, insulin activity and lipid metabolism in lambs. Forty-eight, 9-week-old weaned lambs (Dorper$\times$Small-tail Han sheep, mean initial body weight = $22.96kg{\pm}2.60kg$) were used in a $2{\times}3$ factorial arrangement of supplemental Cr (0 ppb, Cr0; 400 ppb, Cr1; or 800 ppb, Cr2 from chromium yeast) and CP levels (157 g/d to 171 g/d for each animal, LP; or 189 g/d to 209 g/d for each animal, HP). Growth data and blood samples were collected at the beginning and end of the feed trial, after which the lambs were killed. Both Cr additive groups and the HP group increased final weight and average daily gain, especially the Cr1 and HP group (p<0.01). HP increased pelvic fat weight (p<0.05), fat thickness of the 10th rib (p<0.05), longissimus muscle area (p<0.01) and rate of deposition of intramuscular fat (p<0.01). Supplemental Cr decreased the rate of deposition of intramuscular fat (p<0.05). Fasting insulin level and the ratio of insulin to glucose were lower with Cr1 than other groups, but with no significant difference. Glucose concentration was not affected by any treatment. Nonesterified fatty acids increased in the Cr1 (p<0.05) and HP (p<0.05) conditions and there was a significant $Cr{\times}CP$ interaction (p<0.05). Cr1 decreased triglycerides (p<0.05) and total cholesterol (p = 0.151) and HP increased high-density lipoprotein cholesterol (p<0.05). Cr1 decreased lipoprotein lipase activity in subcutaneous adipose tissue (aLPL, p<0.05) and the ratio of aLPL to lipoprotein lipase activity in skeletal muscle (mLPL, p = 0.079). mLPL and hepatic lipase (hHL) were not affected by any treatment. In the present study, Cr had limited effects on growth rate and carcass response, whereas Cr and CP had some notable effects on plasma metabolites and enzyme activities. Cr has a potential effect on energy modulation between lipid and muscle tissue. In addition, few $Cr{\times}CP$ interactions were observed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.3
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• pp.257-261
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• 2009

Two feeding trials were conducted to investigate the effects of several dietary additives on growth and feed utilization of juvenile flounder. In the first experiment, three replicate groups of juveniles (average weight 1.5 g) were fed diets with or without wasabi extract and chitosan for 7 weeks. Survival rate, weight gain, protein efficiency ratio, hepatosomatic index and condition factor were not affected by the different dietary additives (P>0.05). Feed efficiency of fish fed the wasabi extract diet was significantly higher than that of fish fed the control diet (P<0.05). Daily feed intake of fish fed the wasabi extract diet was significantly lower than that of fish fed the other diets (P<0.05). In the second experiment, three replicate groups of juveniles (average weight 1.4 g) were fed diets with or without Pophyra powder for 7 weeks. Survival rate and weight gain were not significantly affected by dietary Pophyra powder (P>0.05). Feed efficiency and protein efficiency ratio of fish fed the Pophyra diet were significantly lower than those of fish fed the control diet (P<0.05). The results of these experiments suggest that feed efficiency of juvenile flounder may be improved by dietary supplementation with wasabi extract.

• Korean Journal of Veterinary Service
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• v.31 no.2
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• pp.229-237
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• 2008

This study was conducted to evaluate the effect of honeybee venom, purified using bee venom collector, and feeding of probiotics on the body weight gain, growth rate and hematological characteristics of pigs. A total of 120 pigs were examined and divided into 4 groups 1) Control (basal diet), 2) BV (basal diet + bee venom), 3) PB (basal diet + probiotics), 4) BVPB (basal diet + BV + PB). Average daily weight gain improved significantly in all test groups, especially BVPB (P < 0.05) compared to the controls. There was a significant difference in the feed conversion rate (P < 0.05) and efficiency (P < 0.05) between BVPB and control pigs. Weight gain and survivability was higher in the tests than the controls, but white blood cell count was not. Serum total protein, albumin and IgG concentration of BVPB were slightly higher than those of controls. These results suggest that treated honeybee venom and probiotics should be used together to effectively increase the productivity of pigs.

• FLOWER RESEARCH JOURNAL
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• v.16 no.4
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• pp.255-259
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• 2008

This study was conducted to investigate the effect of ridge height (10 cm, 20 cm, 30 cm, and 40 cm) on the soil physical property, the growth and flowering characteristics of Gypsophila paniculata (cv 'Bristol Fairy') in the subalpine area. As ridge height got higher, the daily soil temperature, the soil moisture content, soil hardness, bulk density, and solid phase ratio were decreased, but porosity ratio was a little increased. In summer and autumn cultivation the blooming of ridge height 30 cm and 40 cm was slightly delayed, but their root activity, cut flower width, and yield were better than those of 10 to 20 cm ridges. And the mortality ratio of plants, rosette formation rate, and nonpaniculata inflorescence rate became lower.