• Korean Journal of Ichthyology
• /
• v.27 no.2
• /
• pp.95-103
• /
• 2015

Egg development and early life history of the Korean spine loach, Cobitis tetralineata, were investigated in the present study. Adult fish were sampled using spoon nets at the Seomjin River in Jeongsan-ri, Bokheong-myeon, Sunchang-gun, Jeollanbuk-do, Korea, July 2013. Eggs were obtained after injecting Ovarprim into females. Eggs were then artificially fertilized using the Dry method in the laboratory. Mature eggs were slightly adhesive and transparent with grey coloring, and measured $1.04{\pm}0.03mm$ ($mean{\pm}SD$) in diameter. Hatching of the embryo occurred approximately 56 hours after fertilization at $25^{\circ}C$ of water temperature, and the average size of newly hatched larvae was about $4.6{\pm}0.11mm$ in total length. At fifth day after hatching, the larval full length reached $6.8{\pm}0.28mm$ on average and their yolk sac had been completely absorbed. At 17th day after hatching, larva entered the juvenile stage and reached $9.8{\pm}0.50mm$ in total length. At 100th day after hatching, the formation of Gambetta's zone of four line was complete and juveniles were similar in general appearance to adults, and they averaged $34.7{\pm}5.77mm$ in total length.

• Korean Journal of Ecology and Environment
• /
• v.45 no.1
• /
• pp.93-101
• /
• 2012

In the present study, egg development and early life history of Korean spined loach, $Iksookimia$ $koreensis$, were observed. Adult fish were sampled using spoon nets in Okgye-ri, Hoengseong-gun, Gangwon-do, Korea in July 2010. Eggs were obtained after injecting females with Ovarprim. Eggs were then artificially fertilized in the laboratory using the dry method. Mature eggs were slightly adhesive and transparent with a light yellowish color, and measured $1.40{\pm}0.04mm$ (mean${\pm}$SD) in diameter. Hatching of the embryo occurred approximately 50 h after fertilization in the water at $23^{\circ}C$, and newly hatched larvae were averaged $4.7{\pm}0.21mm$ in total length. 5 days after hatching, the averaged total length of larvae was $7.1{\pm}0.25mm$ and their yolk sacs had been completely absorbed. 17 days after hatching, fish started to enter the juvenile stage and reached $12.2{\pm}1.10mm$ in total length. 80 days after hatching, the band patterns and external form of juvenile fish were similar to those of adults, and they averaged $31.0{\pm}3.98mm$ in total length.

• Journal of Plant Biotechnology
• /
• v.45 no.1
• /
• pp.77-82
• /
• 2018

In South Korea, LM crops are not allowed to grow locally, but have been allowed to be imported as food and feed purposes. Currently, the typical LMO imports are continuously increasing in the region of South Korea. In 2014, we carried out a review of the environmental release monitoring of LM maize (Zea mays L.) in Gyeonggi-do of South Korea, and analyzed volunteer samples using strip test kits and polymerase chain reaction (PCR) methods. We thereby collected 44 volunteers of released LM maize in 169 locations around ports, from roadsides, feed factories and stockbreeding farmhouses. We found 4 positive samples at 3 sites using strip test kits. Based on the PCR analysis, the LM maize plants were found using event-specific primers. These results suggested that our monitoring is necessary to detect the presence of released LM maize in the natural environment of South Korea.

• The Korean Journal of Mycology
• /
• v.28 no.1
• /
• pp.32-37
• /
• 2000

The objectives of this study was to identify genetic variations of Tricholoma matsutake (S. Ito et Imai) Sing. growing in different geographic ranges in South Korea. Mushrooms were collected during fruiting seasons from 1994 to 1997 from 11 major sites which included four sites (Bonghwa, UIjin, Goryoung, and Chungdo) in Kyongbuk Province, three sites (Changnyung, Hadong, and Hamyang) in Kyongnam Province, two sites (Yangyang and Inje) in Kangwon Province, one site (Goisan) in Choongbuk Province, and one site (Namwon) in Chonbuk Province. Two mushrooms each from three to eight shiros in each sites were collected. Genetic characteristics were analyzed by Inter-Simple Sequence Repeat Polymerase Chain Reaction (I-SSR PCR) method using six primers. With a total of 131 DNA bands identified, Nei's genetic distance and UPGMA tree were constructed. It was estimated that genetic variations between sites amounted to 12.9%, while 87.1% of total variation was explained by variations among individuals within sites. The cluster analysis indicated that the eleven major sites were clustered into four groups, group I (Yangyang, Hamyang, Inje, Hadong and UIjin), group II (Changnyung, Namwon and Chungdo), group III (Goryoung), and group IV (Bonghwa and Goisan). It is concluded that matsutake mushrooms in South Korea have a considerable degree of genetic variations between major sites.

• Journal of Mushroom
• /
• v.11 no.4
• /
• pp.303-307
• /
• 2013

The cultivation of Poria cocos on tree-stumps and logs, was first described at the beginning of the 13th century. Poria cocos has been used for medicinal purposes to treat physical and mental recuperation, promote diuresis, forgetfulness and physical weakening. The artificial cultivation techniques of P. cocos was reported in China in 1957. are reported. The basic study on morphological characteristics and artificial cultivation method of Poria cocos with pine tree log buried under ground were initiated by Rural Development Administration. To widen the utilization of harvested sclerotia of Poria cocos as new food stuffs, powder of the sclerotia were used for producing new soft drinks and supplemented to wheat flour to make functional bread. Last 30 years, the supply of P. cocos in Korea through cultivation could not meet the domestic demand, Korea collected P. cocos in the mountainous areas and also import the sclerotia from China. Since the domestic demand of the sclerotia in China increased, the price of imported sclerotia of P. cocos also increased. Recently, high-quality and high-yielding cultivation methods were developed in Gyeongbuk Agricultural Research and Extension Services (GARES). The new cultivation methods of P. cocos developed by GARES was to change traditional cultivation method from under ground to above ground cultivation house, and shortened cultivation period by half, and improved the quality of the sclerotia. Therefore, it is suggested that advanced new technology for production of sclerotia of P. cocos from under ground and above ground must be developed for fullfil the domestic demand of the sclerotia.

• Korean journal of applied entomology
• /
• v.23 no.1 s.58
• /
• pp.15-21
• /
• 1984

The virus infecting French bean (Phaseolus vulgaris L.) was identified as Bean Common Mosaic Virus(BCMV) based on the host range, symptomatology, serology, morphology of virus particles and inclusion bodies. Isolates of BCMV were obtained from seeds of P. vulgaris collected at Suweon, Jangsu and Jinju in Korea. French bean produced vein clearing, mosaic, stunting and leaf curling. Symptom of Chenopodium quinoa was local lesions on the inoculated leaves, not on the upper leaves. The electron micrograph of the virus from French bean was flexuous approximately 750nm in length. Cylindrical and pinwheel cytoplasmic inclusion bodies were observed in French bean leaf infected by BCMV. BCMV from the French bean was transmitted through seed and green peach aphid, Myzus persicae. The thermal inactivation point was $55\~60^{\circ}C$, dilution end point was $10^{-3}\~10^{-5}$ and longevity in vitro was $2\~3$ days for BCMV from French bean. The isolates of BCMV reacted positively against BCMV antiserum. The extract of BCMV infected bean leaves, Azukibean mosaic virus (AZMV) and Cowpea aphid borne mosaic virus(CaMV) also reacted with BCMV antiserum, however, BCMV and CaMV showed the spur in agar gel diffusion test.

• Journal of fish pathology
• /
• v.31 no.1
• /
• pp.9-13
• /
• 2018

We previously monitored nervous necrosis virus (NNV) in brain samples of artificially produced walleye Pollock (Gadus chalcogrammus) seedlings, with a low prevalence (1.8%, 1/55) but no clinical symptoms. Given that this virus is considered one of the most serious viral threats for almost all marine aquaculture fish species and characterized by both vertical and horizontal transmission, it would be interesting to monitor NNV in the fertilized eggs as well. We collected fertilized walleye pollock eggs from the farms located in Goseong during January to March, 2017. Approximately 50 mg of eggs were periodically taken from 4 each different batches, and 37 different pooled sample sets in total were made during sampling period. RNA was extracted from the eggs by using Trizol and cDNA was synthesized for RT-PCR for detecting NNV. Primers and PCR conditions are the same as previously described. As a result, NNV was not detected from any of the sample sets by one step PCR (0%, 0/37), suggesting NNV may not be a threat in walleye pollock aquaculture in Korea at present time. However, continuous monitoring for NNV should be conducted because introducing a new species into aquaculture industry involves potentials of disease outbreak and NNV is already known to cause outbreaks in gadoid fishes.

• Korean Journal of Ichthyology
• /
• v.31 no.1
• /
• pp.30-38
• /
• 2019

Egg development and early life history of the Korean endemic sand spine loach, Cobitis nalbanti, were investigated in the present study. Adult fish were sampled using spoon nets at the Yeongsan River in Seongam-ri, Bukha-myeon, Jangseong-gun, Jeollanam-do, Korea, June 2011. Eggs were obtained after injecting Ovarprim into females. Eggs were then artificially fertilized using the dry method in the laboratory. Mature eggs were transparent and slightly adhesive with light yellowish coloring, measured $0.99{\pm}0.03mm$ ($mean{\pm}SD$) in diameter. And number of spawned eggs were $1,527{\pm}410$ per individual. Hatching (50%) of the embryo occurred 52 hours after fertilization a water temperature of $25^{\circ}C$, and the average newly hatched larvae size was about $4.2{\pm}0.22mm$ in total length. At fifth day after hatching, the larval total length reached $6.0{\pm}0.34mm$ on average and their yolk sac had been completely absorbed. At fifteen day after hatching, larva entered the juvenile stage and reached $10.8{\pm}0.45mm$ in total length. At 100th day after hatching, the formation of Gambetta's zone of four dotted line was complete and juveniles were similar in general appearance to adults, and they averaged $41.1{\pm}2.95mm$ in total length.

• Journal of Advanced Navigation Technology
• /
• v.11 no.2
• /
• pp.154-162
• /
• 2007

This paper verifies the performance of the wireless-signal map-matching (WSMM) method that is recently proposed to mitigate the effects of non-line-of-sight (NLOS) error in positioning under wireless terrestrial network environments. The WSMM method is the new positioning technology that estimates and compensate the NLOS errors by processing the bulks of anonymous measurements at unknown locations that are collected randomly and automatically. The WSMM method would be advantageous for various configurations of future ubiquitous sensor networks since it is based on the existing network configuration for communication and it requires no additional hardware in base stations and mobile handsets. It is shown that the application of the WSMM concept to the real CDMA pilot strength measurment message (PSMM) actually mitigates the NLOS error effects and improves overall positioning accuracy.

• Analytical Science and Technology
• /
• v.18 no.4
• /
• pp.329-337
• /
• 2005

TL dating using pre-dose effect is concerned with the sensitivity increase of $110^{\circ}C$ TL peak in quartz following the pre-exposure of irradiation (pre-dose) in antiquity and heating to thermal activation temperature. Using the multiple activation (MA) method for determining an equivalent dose, the activation temperature was selected to $500^{\circ}C$ and the region of interest was selected from $85^{\circ}C$ to $105^{\circ}C$ on quartz sample from archaeological remains, roof-tile kiln. which was excavated at Chudong-Ri cultural site. It was concluded that the resultant date was determined to the age of $1725{\pm}25years$ AD (l ${\sigma}$ SD), which had more improved precision considering with e radiocarbon dates and was in good agreement with the age derived by archaeological assessment. Also it was concluded that the pre-dose dating should contribute significantly to future archaeological dating work in the range of the last 2000 years.