• Korean Journal of Organic Agriculture
• /
• v.22 no.4
• /
• pp.743-760
• /
• 2014

This study aimed to isolate and identify freshwater algae from the organic agricultural ecosystems and investigate its biological characteristics to study the possibility of utilizing a biomass freshwater algae in organic farming. In the survey area, average water temperature was $12.4{\sim}28.2^{\circ}C$ and the pH ranges were from 6.1 to 8.5. The solid culture method is more suitable than liquid culture method for isolation of freshwater algae with lower contamination level and higher isolation frequency. A total of 115 strains were isolated from six freshwater algae habitats in nine regions in Korea. BGMM (BG11 Modified Medium) amended with NaNO3 and $KNO_3$ as a nitrogen, and $Na_2CO_3$ as carbon source was designed to isolate and culture freshwater algae. Absorbance of freshwater algae culture has increased dramatically to four days and decreased after eight days after inoculation. CHK008 of the seven isolates showed the highest absorbance in seven days after culturing in BGMM. The optimal pH of BGMM for culturing freshwater algae was pH 6-7. As light intensity increased, growth of freshwater algae increased. Among the five kinds of carbon sources, glucose and galactose promoted good growth of freshwater algae in BGMM. The colony color of purified 16 green algae isolates showed a separation of green, dark and light green, and of them, eleven algae strains showed a strong fluorescent light under fluorescence microscopy. Cell size of the green algae showed a wide range of variation depending on the species. General morphology of the green algae strains was spherical. Chlamydomonas sp. was elliptical, and Chlorella sorokiniana was ellipsoidal and cylindrical. All strains of the green algae except for Chlamydomonas sp. did not have flagella. One isolate of Chlamydomonas sp. and five isolates of C. sorokiniana secreted mucus. Sixteen isolates of 16 green algae were identified as two family and six species, Chlorella vulgalis, C. sorokiniana, C. pyrenoidosa, C. kessleri, C. emersonii, and Chlamydomonas sp. based on their morphological characteristics.

• Science of Emotion and Sensibility
• /
• v.23 no.4
• /
• pp.105-116
• /
• 2020

The purpose of this study is to progress the limitations and disadvantages of existing safety clothing by applying high technology to current safety clothing that is produced and distributed only with fluorescent fabrics and retroreflective materials. Therefore, the industrial suspender-type safety belt and engineering technology are introduced, designed, and fabricated to help save a life in an emergency. First, the suspender-type safety belt to be developed is designed to emit light by LED attached to the film, and the body of the belt-wearer is recognized from a distance through retroreflection from the flashing LED. It aims to support people's safety by preventing accidents during roadside work, rescue activities, and sports activities at night. Second, with the development of advanced devices when the user is in an unconscious state due to distress or falls into an unconscious state due to distress or accident, the tilt sensor of the control unit attached to the belt automatically detects the angle of the human body and generates light and sound. It is intended to further enhance the utilization by mounting a sensing and signaling device that generates a distress signal and shaping it in the form of a belt attached to a vest that can be easily detached from the outside of the garment. When the wearer falls due to an accident, the tilt sensor of this belt detects the angle change and then the controller generates a high-frequency sound and repeated LED blinking signals at the same time. In the case of conventional safety vests, it is almost impossible to detect that the person is wearing a vest when there is no ambient light, but in case of the safety belts in this study, the sound and light signals of the safety belt enable us to find the wearer within 100 meters even when there is no ambient light.

• Journal of Animal Science and Technology
• /
• v.50 no.6
• /
• pp.807-818
• /
• 2008

This study was conducted to prove the optimum feeding method of Lactobacillus in broiler chickens by investigating the intestinal viability of ingested Lactobacillus and the effect of feeding levels and frequency of Lactobacillus on growth performance in broiler chickens. In experiment 1, A total of one hundred, 5 weeks old male broiler chickens(Abor Acre) were fed Lactobacillus reuteri avibro2 expressed green fluorescent protein(GFP) at 104cfu/g diet to investigate the retention time of ingested Lactobacillus in the intestine for 1 day. The percentage of Lactobacillus expressed GFP in intestinal contents was 26% at 1 day after fed Lactobacillus expressed GFP. The percentage of Lactobacillus expressed GFP in intestinal contents was decreased in length of time. In experiment 2, A total of four hundred eighty, 1-d-old male broiler chicks(Abor Acre) were randomly divided into 4 groups with 4 replicates of 30 birds each to prove the optimum feeding level of Lactobacillus. The treatments were control(free antibiotics), Lactobacillus reuteri avibro2 5.0×10cfu/mL, 5.0×103cfu/mL, and 5.0×105cfu/mL. The final body weight and body wight gain of Lactobacillus reuteri avibro2 5.0×103cfu/mL were the highest in all groups(P<0.05). Feed conversion ratio was not significantly difference among the groups. The number of intestinal lactic acid bacteria in Lactobacillus treated groups tended to be improved or significantly increased as compared to that of control(P<0.05). Protein and fat digestibility in Lactobacillus 5.0×103cfu/mL and 5.0×105cfu/mL treated groups were significantly improved(P<0.05). No significant differences were observed on the availability of dry matter and crude ash in Lactobacillus treatments compared to those of control. In experiment 3, A total of six hundred 1-d-old male broiler chicks(Abor Acre) were randomly divided into 4 groups with 4 replicates of 30 birds each and were fed Lactobacillus reuteri avibro2 at intervals of 1, 2, 3, and 5 day for five weeks. Feeding level of Lactobacillus was 5.0×103cfu/mL The final body weight and body wight gain of Lactobacillus reuteri avibro2 5.0×103cfu/mL were the highest in all groups(P<0.05). The final body weight and body weight gain were significantly increased, when Lactobacillus was fed at intervals of 1 days, or 2 days. There were no significant differences in feed intake and feed conversion ratio among the all groups. The number of intestinal lactic acid bacteria in Lactobacillus treated groups tended to be improved or significantly increased as compared to that of control(P<0.05). No significant differences were observed on the number of coliform bacteria and Salmonella of ileum and cecum. Consequently, supplemental Lactobacillus influenced positive effects on the growth performance, nutrient availability and intestinal microflora. The optimum feeding level of Lactobacillus was 5.0×103cfu/mL, and the constant feeding of Lactobacillus was effective.