• Electrical & Electronic Materials
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• v.10 no.2
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• pp.134-140
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• 1997

PbTiO$_{3}$-PbZrO$_{3}$-Pb(Ni$_{1}$3/Nb $_{2}$3/O$_{3}$)(PZT-PNN) thin films were prepared from corresponding metal organics partially stabilized with diethanolamine by the sol-gel spin coating method. Each mol rates of PT:PZ:PNN solutions were #1(50:40:10), #2(50:30:20), #3(45:35:20) and #4(40:40:20), respectively. The spin-coated PZT-PNN films were sintered at the temperature from 500.deg. C to 600.deg. C for crystallization. The P-E hysteresis curve was drawn by Sawyer-Tower circuit with PZT-PNN film. The coercive field and the remanent polarization of #4(40:40:20 mol%) PZT-PNN film were 28.8 kV/cm and 18.3 .mu.C/cm$^{2}$, respectively. Their dielectric constants were shown between 128 and 1120, and became maximum value in MPB(40:40:20 mol%). The leakage currents of PZT-PNN films were about 9.4x 10$^{-8}$ A/cm$^{2}$, and the breakdown voltages were about 0.14 and 1.1 MV/cm. The Curie point of #3(45:35:20 mol%, sintered at 600.deg. C) film was 330.deg. C.

• Journal of Korean Society of Forest Science
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• v.95 no.5
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• pp.543-550
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• 2006

Distribution patterns of two pine sawyer species (Monochamus alternatus which is the main vector insect and M. saltuarius which is the potential insect vector of the pine wood nematode) were investigated in Korea. The data were collected at 89 study sites which were chosen to cover the whole region of South Korea. The selected pine trees were killed in early April and left for I year in the pine stands to be egg-laid by the pine sawyers. Emergence of the beetles from the dead pine trees was checked from early April to late July. M. saltuarius was the most abundant in the mid to northern areas of South Korea, whereas M. alternatus in Jeju-do, southernmost island of Korea. Considering temperature distribution patterns in areas where the two species occur, their thermal distribution boundary may be formed around $13.2^{\circ}C$ of annual mean temperature. The hypothesized distribution map of the two Monochamus species under the invasion of pine wilt disease is suggested on the base of thermal distribution of Korean peninsula.

• Korean journal of applied entomology
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• v.56 no.2
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• pp.187-193
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• 2017

The Japanese pine sawyer, Monochamus alternatus Hope, is a representative vector of the pine wood nematode, Bursaphelenchus xylophilus, which causes wilting symptoms in pine trees. A control method using a net has been introduced, which is an alternative method to the fumigation for the control of dead pine trees by pine wilt disease. This study was carried out to investigate the factors that induce gnawing and escaping behaviors of M. alternatus. The behaviors were examined after M. alternatus adult was placed in a confined space at different temperatures. M. alternatus adults could escape through mesh net torn by gnawing when they were confined in a space of 30 mm or less in diameter. The success rate of escape was high at 20 to $30^{\circ}C$, and no adults escaped at $15^{\circ}C$. The enticement of M. alternatus adults by food didn't affect the success rate of escape. In the case of not being confined in a narrow space, the escaping hole could not be formed because the gnawing was not concentrated on one part. M. alternatus moved its body in a narrow space using the tarsus of middle and hind legs, and made an escape hole by concentrically gnawing the obstacle on the front side with mandible, and showed a behavior of getting out while supporting the body by supporting the front legs. The present results will be able to use as an important basic information for evaluating the performance of mesh net which confines M. alternatus adults and suggested by alternative method to fumigation technology.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.391-396
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• 2008

The pine sawyer, Monochamus saltuarius Gebler (Colepotera: Cerambycidae) was newly known as a vector of pinewood nematode causing the pine wilt disease in Korean white pine (P. koraiensis Siebold & Zucc.) forestry. Recently, it has a serious problem to spread fast and widely throughout Korea by transferring M. saltuarius. For the control of M. saltuarius, this study was investigated the attractants by analyzing from the Korean white pine. Major components of Korean white pine was analyzed as $\alpha$-pinene and ethanol, and reported as an attractant against Monochamus genus. Ipsenol and ipsdienol, the pheromones of Ips genus known as attractant components of woodboring beetles, were tested to the attractive efficacy against Monochamus saltuarius. The attractive efficacy showed 67.9% of Ipsenol plus ipsdienol and ipsenol, ipsdienol mixed with $\alpha$-pinene plus ethanol was showed 67.7% and 79.3%, respectively. Especially, ipsdienol with $\alpha$-pinene and ethanol was shown the high synergy effect, and the attractant effect was higher at M. saltuarius female than male.

• Journal of Life Science
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• v.25 no.12
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• pp.1445-1449
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• 2015

The pinewood nematode Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae) poses a serious threat to pine forests in Europe and East Asia, leading to a debilitating pine wilt disease. Infected pine trees in Korea are generally fumigated or crushed to small wood chips after felling. Although pine wilt disease often recurs in pest management sites, there are no adequate means to monitor the effectiveness of pest control measures in those sites. Recently, a male-produced aggregation pheromone, 2-(undecyloxy)ethanol, was shown to be useful for attracting several Monochamus species, which are vectors for the pinewood nematodes. In this study, we investigated the abilities of 2-(undecyloxy)ethanol at three different doses (175, 350, and 700 mg), as well as host plant volatiles (α-pinene and ethanol), to attract M. alternatus (Coleoptera: Cerambycidae) at a pine forest in Pohang, Korea where infected pine trees had been cut down and fumigated. Twenty-seven M. alternatus were captured in cross-vane panel traps made of polyethylene terephthalate bottles and acrylic sheets. The results indicate that a high dose of 2-(undecyloxy)ethanol (700 mg per trap) is the most effective for attracting M. alternatus. The aggregation pheromone could be used to monitor the effectiveness of pest control measures as well as M. alternatus populations.

• Korean Journal of Animal Reproduction
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• v.10 no.1
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• pp.100-108
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• 1986

Eik-Nes (1966) reported that the mechanism of spermatogenesis is controlled by FSH and LH and maintaned normally in scrotum terperautre which is 3-5$^{\circ}C$ lower than body termperature. But Ojeda and Ramirez (1972) have described that the abdominal testis was shrinked severely and lost its normal function in congenital cryptorchidism or surgically induced cryptorchidism. Ramirez and Sawyer (1974) reported that the compensatory hypertorphy occured in the remaining testis of unilateral castration and the scrotal testis of unilateral cryptorchidism. Cunninham et al. (1978) reported that the serum FSH levle increased after unilateral castration. Frankel and Wright (1982) reported that the serum LH level was unchanged greatly after unilateral castration. Gomes and Jain (1976) reported that the serum testosterone level increased temporarily but not varied after unilateral castration. On the other hand, Kormano et al. (1964) reported that the serum FSH level in unilateral cryptorchidism rat was unchanged in contrast with the control and Risbirdger et al. (1981) reported that the serum LH level was unchanged till 2 weeks after operation and after then increased to 77%. Kim (1984) reported that the serum testosterone level was somewhat lower than that fo control group but there was't significant different. There were many different reports on hormone levels among different investigators when the immarue rats were castrated unilaterally or induced cryptorchidism unilaterally. Liang and Liang (1970) and Cunningham et al. (1978) described that there were no true compenastory hypertrophy in the remaining testis of unilateral castration and scrotal testis of unilateral testis of unilateral cryptorchidism in rat but they grew faster than that of control. Kormano et al.(1964), Damber et al.(1976), Cunningham et al.(1978) and Karpe et al.(1981) reported that the testis weight, germinal epithelia height and seminiferous tubules diameter developed continuously and similarily in the control, the remaining testis of unilateral castration and scrotal testis of unilateral cryptorchidism increased, however, in the abdominal testis of the unilateral cryptorchidism, they were much smaller than those of other groups. In observation of the histological changes in the seminiferous epithelium of control, remaining tesis of unilateral castration and scrotal testis of unilateral cryptorchidism differentiated and developed fully(Cunningham et al., 1978). However, the abdominal testis of unilateral crytorchidism degenerated severely and only the germ cells in early stage and Sertoli cells were found in the seminiferous tubules. (Damber et al., 1976, Gomes and Jain, 1976 and Karpe et al., 1981). By electron microscopic observation, Nagano (1963) and Leason and Leeson (1970) found that the abdominal testis of unilateral cryptorchidism was thicked in boundary tissue, increased lipid droplet in the Sertoli cell, disarranged axial filament complex and increased lipid inclusions in the Sertoli cell.

• Interdisciplinary Bio Central
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• v.4 no.3
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• pp.10.1-10.12
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• 2012

Introduction: We investigated frameshift suppressor tRNAs previously reported to use five-base anticodon-codon interactions in order to provide a collection of frameshift suppressor tRNAs to the synthetic biology community and to develop modular frameshift suppressor logic devices for use in synthetic biology applications. Results and Discussion: We adapted eleven previously described frameshift suppressor tRNAs to the BioBrick cloning format, and built three genetic logic circuits to detect frameshift suppression. The three circuits employed three different mechanisms: direct frameshift suppression of reporter gene mutations, frameshift suppression leading to positive feedback via quorum sensing, and enzymatic amplification of frameshift suppression signals. In the course of testing frameshift suppressor logic, we uncovered unexpected behavior in the frameshift suppressor tRNAs. The results led us to posit a four-base binding hypothesis for the frameshift suppressor tRNA interactions with mRNA as an alternative to the published five-base binding model. Conclusion and Prospects: The published five-base anticodon/codon rule explained only 17 of the 58 frameshift suppression experiments we conducted. Our deduced four-base binding rule successfully explained 56 out of our 58 frameshift suppression results. In the process of applying biological knowledge about frameshift suppressor tRNAs to the engineering application of frameshift suppressor logic, we discovered new biological knowledge. This knowledge leads to a redesign of the original engineering application and encourages new ones. Our study reinforces the concept that synthetic biology is often a winding path from science to engineering and back again; scientific investigations spark engineering applications, the implementation of which suggests new scientific investigations.

• Journal of Korean Society of Forest Science
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• v.100 no.2
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• pp.165-171
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• 2011

This study was conducted to investigate the effect on pine wilt disease by health-thinning, thinning and sapling tending in red pine forest (Pinus densiflora). As a part of developing forestry control methods for pine wilt disease control. In case of putting in pine sawyer (Monochamus alternatus) with pine wood nematode (Bursaphelenchus xylophilus), the specimen trees in health-thinning, thinning and control treatment were withered more than 50%, although there were not statistically significant differences in treatments. In treatment site, thinning slashes had influenced on the spread of pine wilt disease (experiment 1). In thinning stand of sapling pine, site with thinning slashes had highest mortality (> 90%). There were approximately 10% mortality in the site of carried thinning slashes from case and the site of non-thinning with released M. alternatus (experiment 2). The larvae had not appeared in young tree stump with health-thinning and thinning at April, the current emergence year of M. alternatus, but there were larvae in sapling tree stump with thinning at May, the current emergence year of M. alternatus. In case of stands with infected young and sapling tree by pine wilt disease, there is no effects of on pine wilt disease control by health-thinning, thinning, saplings tending at April and May, the current emergence year of M. alternatus, and leaved thinning slashes had influenced on the spread of pine wilt disease as habitation of M. alternatus.

• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.352-358
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• 2011

Field Cage plots ($1m{\times}1m{\times}1m$) were established (7 units) to find the lowest limit time about the tending of red pine forest (Pinus densiflora) which can no longer be used as a habitat by Monochamus alternatus, vector insect of pine wilt disease at the experimental forest of the southern forest research center of the Korea forest research institute in February in 2010. Thinning slashes (length, 1 m; diameter, 5~10 cm) tended at the different times were put in cages, and 4~6 couples of adult M. alternatus were put into each the cage in June. Presence or absence the larval entrance holes and larval were determined in November in 2010. Incase of the combination 24, 18, 12 and 6-month-old thinning slashes from thinning times to the time of adult emergence inside a single cage, larval entrance holes were found in the 6-month-old and 12-month-old thinning slashes but larvae were found only in the 6-month-old thinning slashes (treatment 1). In case of the combination 24, 18, 15 and 12-month-old thinning slashes inside a single cage, larval entrance holes were found in the 15-month-old and 12-month-old thinning slashes but larvae were found only in the 12-month-old (treatment 2). When 24, 18, 15, 12 and 6-month-old thinning slashes with treated dry and humid condition were put separately inside each cage, larval entrance holes were found in the 18, 15, 12, 6-month-old thinning slashes without the relation of the dry and humid conditions. But larvae were found in the 15, 12, 6-month-old thinning slashes in the dry conditions and only in the 6-month-old thinning slashes in the humid conditions. Results indicated the lowest limit time which can no longer be used as a habitat by M. alternatus is before 24 month from the time of adult emergence.