We demonstrated an effective way of preparing melt spinnable mesophase pitches via catalytic hydrogenation of petroleum residue (fluidized catalytic cracking-decant oil) and their subsequent thermal soaking. The mesophase pitches thus obtained were analyzed in terms of their viscosity, elemental composition, solubility, molecular weight, softening point and optical texture. We found that zeolite-induced catalytic hydrogenation under high hydrogen pressure contributed to a large variation in the properties of the pitches. As the hydrogen pressure increased, the C/H ratio decreased, and the solubility in n-hexane increased. The mesophase pitch with entirely anisotropic domains of flow texture exhibited good meltspinnability. The mesophase carbon fibers obtained from the catalytically hydrogenated petroleum residue showed moderate mechanical properties.
목적 : 본 연구에서는 표전 근전도 신호를 기반으로 기존의 재활로봇 알고리즘의 성능의 개선하기 위한 새로운 특징 요소를 개발 및 검증하였다.
연구방법 : 기존의 선형 재귀 모델을 기반으로 한 실시간 로봇 제어 알고리즘을 수정하여, 2개 이상의 주파수 특징을 가지는 근 전도신호에 그 특징의 수에 맞추어 주파수 영역을 다르게 한 모델을 개발하였다.
결과 : 측정된 결과 개선된 알고리즘의 모델이 기존 모델대비 높은 정확도가 나옮을 확인할 수 있었으며, 향후 이를 적용 한다면, 근전도 기반 재활로봇의 정확도가 향상될 수 있음을 확인할 수 있었다.
결론 : 본 연구에서 제안된 복수의 필터뱅크 특징을 기반으로 한 개선될 선형 재귀알고리즘이 기존 알고리즘보다 높은 성능을 보임을 확인할 수 있었다. 이를 바탕으로 향후 뇌졸중 환자의 치료를 위한 재활 로봇을 제어하는데 활용된다면, 환자의 의지를 더욱 정확히 반영한 재활치료를 통하여 환자의 재활치료효과를 증진시킬 것이라 기대된다.
Plant-parasitic nematodes causes yield losses of more than $100 million per year in the world. Among them, soybeancyst nematode (Heterodera glycines Ichinohe) causes the greatest yield loss to soybean compared to any other pest worldwide.SCN causes yield reductions by feeding on plant nutrients, retarding root growth and inhibiting Bradyrhizobium japonicum(Kirchner) Buchanan nodulation. The primary methods for controlling SCN include planting resistant cultivars and rotationwith nonhost crop. In order to control SCN, we should be breeding resistant soybean cultivars which has resistant genefor this pest. The research that can minimize the damage of the soybean yield is still insufficient, comprehensive andsystematic research is urgently required. Current researches in our lab are discussed.
The entomopathogneic fungal colonization has become an interesting issue in ecological pest management. Plant-orientedfungi induce plant growth promotion and act as natural control agents against insect pest. Herein this work, we evaluatedthe ability of fungal colonization on bark, branches and leaves of pine tree (Pinus densiflora) to select optimal candidatesfor controlling Japanese pine sawyer (Monochamus alternatus), which is the pine wilt disease vector in Korea. As a result,some Beauveria and Metarhizium isolates could colonize on the substrates of P. densiflora and showed pathogenicity againstM. alternatus. This result suggests that the selected entomopathogenic fungi are possibly candidates for long-term managementof M. alternatus in pine tree forest.
Japanese pine sawyer, Monochamus alternatus HOPE (Coleoptera: Cerambycidae) are considered as important pine forestinsect pests in several countries which transmits the pine wood nematode, Bursaphelenchus xylophylus. In this study, wetried to control Japanese pine sawyer using entomopathogenic fungi to prevent the spread of pine wilt disease in Korea.Several entomopathogenic fungi were exposed to the adults of Japanese pine sawyer and mycosis was observed in themembranous cuticles after 6 days. In particular, two isolates showed high virulence against the adults. The selected 2isolates were sprayed to the adults at 1×105, 1×106 and 1×107 conidia/ml. In the concentration of 1×107 conidia/ml, thesurvival rates of insects were 40% and 47%, respectively. Based on these results, the possibility of controlling the Japanesepine sawyer was confirmed.
Community and guild structures were investigated in 5 regions (Cheorwon, Icheon, Buan, Haenam, Ulsan) in 2016.A total of 4,806 spiders were collected and identified as 73 species of 48 genera in 17 families. Species compositionand abundance were high in Linyphiidae, Tetragnathidae and Lycosidae. Average species richness index was 28.27±0.72,abundance was 320.40±28.41 and diversity index was 2.49±0.06. Guild of rice field spiders were categorized 8 ecologicallyfunctional groups; Space web builders, Wandering sheet weavers, Orb weavers, Ground runners, Ambushers, Stalkers, Sheetweb builders and Foliage runners. Their abundance was high in ground runners with 167.00±24.12 and low in sheet webbuilders with 0.73±0.23. In species diversity, ground runners was high with 1.30±0.07 and stalkers was low with 0.31±0.09.
Until recently, molecular detection method for Bursaphelenchus xylophilus (Bx) infesting pine trees and killing themhas been developed several ways such as RFLP, Real-time PCR and LAMP. However, these were not only time-consumingprocess but also could not confirm the result in a short time. Furthermore, these methods also need thermo cycler orthermostat which are not portable and inexpensive. For above reasons, we had been developed the detection method forBx remaining in the pinewood chips without using electronic devices. In this study, we had used DUNT buffer that isable to extract genome DNA from Bx in the pinewood within 10 min and isothermal amplification that could be amplifiedthe specific DNA fragment of Bx at 37 ℃ for 10 min. As a result, our method is able to confirm the presence or absenceof Bx in pine trees within 20 min and could be used in the field as it does not require the electronic devices.
The distribution of mosquitoes collected in Cheongju area in 2016 and 2017 were compared. The collection sites wereestablished from residential area, migratory bird sanctuary, and cattle feedlot using BL trap and BG trap. Culex pipienswere the most collected in residential area, and Aedes vexans were the most collected in migratory bird sanctuary andcattle feedlot in both years. BG trap was more collected than BL trap in residential area and migratory bird sanctuary.However, cattle feedlot was more collected in BL trap. A variety of mosquito species were collected from BG trap thanBL trap. However, the number of Anopheles sinensis collected in cattle feedlot showed significant differences betweenBL trap and BG trap. Based on the results of this study, it is considered that effective monitoring of mosquitoes mightbe done by using appropriate trap type according to the region
We have surveyed the current status of insect pollinator use for horticultural crops in 2016. The use rate and farmnumber of insect pollinators for 26 horticultural crops were 25.8% and 55,208, respectively. The colony number of insectpollinators used in this survey was 479,777, which include 344,690 for honeybees, 119,104 for bumblebees, 2,415 formason bees, 1,317 for flies, and 2,415 for the combination of bumblebees, honeybees, and mason bees. The use rateof insect pollinators was 59.4% for 11 vegetable crops and the colony number of insect pollinators used for 11 vegetablecrops was 449,287. The colony number of insect pollinators used for 15 fruit tree crops was 30,290, which include honeybees(66.3%), bumblebees (20.2%), mason bees (8.0%), flies (1.6%), and the combination (3.9%) of bumblebees, honeybees,and mason bees. Together, farms of 98% showed positive effect for the use of insect pollinators and most of farms (97.0%)planed for the continuous use of insect pollinators
We have analyzed the transcriptome of Scolopendra subspinipes mutilans using RNA sequencing and identified severalantimicrobial peptide candidates. Among the peptides, named scolopendrasins, were selected based on the physicochemicalproperties of antimicrobial peptides via an in silico analysis. As a result, we evaluated the antimicrobial activities ofscolopendrasins against Gram positive and negative bacteria including Candida albicans by radial diffusion assay and colonycount assay. We also investigated the cytotoxicity of scolopendrasins through hemolysis assay. We found that the actionof scolopendrasins involved binding to the surface of microorganisms via a specific interaction with lipopolysaccharides,lipoteichoic acid, and peptidoglycans, which are components of the bacterial membrane. These results will provide a basisfor developing therapeutic agents such as peptide antibiotics.
To investigate the proper eclosion condition of Black Soldier Fly(BSF), Hermetia illucens was investigated the eclosionperiod and rate by cluster size and temperature for 3 weeks. Respectively, ten pupaes were added to the pupae(FTP)and rice husk (TTR) at 25℃, also treated only with pupae(TTR) and rice husk (TTR) at 30℃. In addition, Four hundredpupaes of each pupa were treated with only pupa (SP) and rice husk(SR) at 25℃, while was tested only pupa(TP) andrice husk(TR) at 30℃. As a result of the small group experiment, the FTR group showed the highly rate of emergencerate of 96.6%, which was more efficiently than other treatments, and also, TR group showed of highly efficiency (96.25%).Compared to the small group experiment, the algebra rate and algebra rate averaged 1.1 days faster and increased by13.3%. Two experimental results showed that eclosion rate was influenced by temperature and eclosionrate by shelter.
Environmental cleansing insect which is well known for Black Soldier Fly(BSF), Hermetia illucens egg mass wightby hatch survival rate and animal carcass and pig feces decomposition ability trial and examined survival rate. BSF eggmass examined A-1,2,3 group each 4.56g equivalent condition hatch after survival rate, Survival BSF larva was36,394.67±3,038.863, survival rate average was 64.8%. Put the BSF larva 45,000 into the Python regius carcass showeddecomposition takes 9 days, wight was decreased rate to 67%. Put A-1,2,3 survival BSF larva dived half into pig feces,carcass. Pig carcass, feces each 6.35kg decomposition take 12 days, 14 days, wight decreased rate to 58.8%, 63.2%, Survivalrate showed to 4.87%, 85.6%, one larva per 1.16g, 2.26g pig carcass, feces take decomposition. Since the lack of food,BSF larva didn’t grow more than the pig carcass feed group, extra in 6kg of pig feces feed. Amount pig feces take12.35kg decomposition during 32 days. Manure make 4.2kg.
Chemical pesticides have been used for persimmon pest control, however the overuse caused insect resistance andenvironmental toxicity. Herein this work, we investigated the biological potential of eco-friendly organic pesticides (biologicals)and entomopathogenic fungi in controlling persimmon pests, Stathmopoda masinisaa and Riptortus pedetris. A botanicalmixture of Chinese scholar tree, goosefoot and subtripinnata extract, Bacillus thuringesis NT0423 and one isolate of Beauveriabassiana showed high insecticidal activity against the pests in laboratory conditions. The selected botanical extract andmicroorganism were combined with a chemical pesticide (buprofezin+dinotefuran WP) and were assessed their controlefficacy in persimmon fields. Compared to the three times of chemical spray, the combination of more than one timeof chemical spray and the selected biologicals controlled the persimmon pests with an acceptable levels. Consequentlyone time of biological spray can be integrated to the spray program where only chemicals are strongly considered.
The hard tick, Haemaphysalis longicornis (Ixodida: Ixodidae) is one of the vectors of severe fever with thrombocytopeniasyndrome virus (SFTSV) causing in humans, however little consideration was given to the biological control of the pest.We evaluated three bioassay methods, such as spray, dipping and dropping. As a result, the dipping method was themost efficient way to measure the fungal virulence. Finally, we constructed a Haemaphysalis longicornis pathogenic fungallibrary to further facilitate the resources to be used as potential biological control agents. A conidial suspension of 1×107conidia/ml was exposed to the ticks by dipping. We confirmed that some isolates were highly virulent to the ticks. Thisresults indicated that some fungi could be used to effectively control the Haemaphysalis longicornis.
Nitiric oxide (NO) and eicosanoids function as crucial immune mediators in insects. This study focuses on cross-talkbetween two immune mediators in term of humoral immune response in Spodoptera exigua. Up-regulation of eight differentanti-microbial peptides (AMP) was observed against bacterial challenge. In contrast, injection of E. coli along with L-NAMEsignificantly down regulation the AMP production whereas D-NAME was not effective. The injection of E. coli withdexamethasone or SNAP also decreased AMP production whereas arachidonic acid (AA) compensated the dexamethasoneeffects. RNA inerferece against SeNOS showed the down-regulation of defensin mRNA level, whereas dsNOS injectionswith AA reversed the gene regulation.