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        검색결과 146

        42.
        2018.10 구독 인증기관·개인회원 무료
        The hypopharyngeal gland (HPG) of the honeybee worker produces royal jelly (RJ) and has a developmental cycle closely related to the division of labor. In this study, we investigated to compare the HPG acini diameter of differently aged worker bees with high royal jelly producing colony (HRC) or less producing colony (LRC). Additionally, we also evaluated whether the fresh weight of the head is a reliable indicator of the developmental status of HPG. The HRC showed a significantly higher RJ production about two-times as compared with those of the LRC. We measured the HG-diameters on days 1, 3, 6, 9, 12, 15. The microscopic analysis revealed that the acini size of the HRC was significantly larger than the LRC. In addition, the acini diameter of HRC was 15% longer than the LRC on the first day after emerging. It was shown that the fastest development during 3 days which is preparing for nurse the brood. The HPG acini diameters increased in both colonies in a similar fashion until day 12 and then decreased. We also compared the fresh head weight of the experimental colonies, differences were similar to the development of HPG. Therefore, high royal jelly production may have a positive correlation between HPG acini size and the fresh head weight.
        43.
        2018.07 KCI 등재 구독 인증기관 무료, 개인회원 유료
        TiO2-doped activated carbon fibers (ACFs) were successfully prepared as capacitive deionization (CDI) electrode materials by facile ultrasonication-assisted process. ACFs were treated with titanium isopropoxide (TTIP) and isopropyl alcohol solutions of different concentrations and then calcinated by ultrasonication without heat-treatment. The results show that a certain amount of anatase TiO2 was present on the ACF surface. The specific capacitance of the TiO2-doped ACF electrode was remarkably improved (by 93.8% at scan rate of 50 mV s–1) over that of the untreated ACF electrode, despite decreases in the specific surface area and total pore volume upon TiO2 doping. From the CDI experiments, the salt adsorption capacity and charge efficiency of the sample with TTIP percent concentration of 15% were found to considerably increase by 71.9 and 57.1%, respectively. These increases are attributed to the improved wettability of the electrode, which increases the number of surface active sites and facilitates salt ion diffusion in the ACF pores. Additionally, the Ti-OH groups of TiO2 act as electrosorption sites, which increases the electrosorption capacity.
        4,000원
        44.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Porcine spermatogonial stem cells (SSCs) prefer three-dimensional (3D) culture systems to 2D ones for the maintenance of self-renewal. Of the many 3D culture systems, agar-based hydrogels are candidates for supporting porcine SSC self-renewal, and there are various types of agar powder that can be used. In this study, we sought to identify an agar-based 3D hydrogel system that exhibited strong efficacy in the maintenance of porcine SSC self-renewal. First, 3D hydrogels with different mechanics were prepared with various concentrations of Bacto agar, lysogeny broth (LB) agar, and agarose powder, and the 3D hydrogel with the strongest alkaline phosphatase (AP) activity and greatest increase in colony size was identified for the different types of agar powder. Second, among the porcine SSCs cultured in the different 3D hydrogels, we analyzed the colony formation, morphology, and size; AP activity; and transcription and translation of porcine SSC-related genes, and these were compared to determine the optimal 3D hydrogel system for the maintenance of porcine SSC self-renewal. We found that 0.6% (w/v) Bacto agar-, 1% (w/v) LB agar-, and 0.2% (w/v) agarose-based 3D hydrogels showed the strongest maintenance of AP activity and the most pronounced increase in colony size in the culture of porcine SSCs. Moreover, among these hydrogels, the strongest transcription and translation of porcine SSC-related genes and largest colony size were detected in porcine SSCs cultured in the 0.2% (w/v) agarose-based 3D hydrogel, whereas there were no significant differences in colony formation and morphology. These results demonstrate that the 0.2% (w/v) agarose-based 3D hydrogel can be effectively used for the maintenance of porcine SSC self-renewal.
        4,000원
        46.
        2017.10 구독 인증기관·개인회원 무료
        In recent years, not only the cultivation area of Jujube in Korea but also the number of pest species has increased.The farmers farming environmentally friendly are in great difficulty because there are no effective control materials. Thisstudy was conducted to investigate the control effect of the environment friendly materials on two pest species (Caposinasasakii and Spodoptera litura) in jujube orchard. As a result, Sophora extract and paraffin oil showed over 70% controlefficacy to the C. sasakii and Sophora extract show over 90% control efficacy to the S. litura. Therefore, Sophora extractand paraffin oil were thought to be a envionment friendly effctive materials in controlling the C. sasakii and S. litura.
        47.
        2017.10 구독 인증기관·개인회원 무료
        The diamondback moth, Plutella xylostella is one of the world’s major pests. Economic cost to control this pest wasestimated between US$1.3 billion and US$2.3 billion based on management costs. Conservative estimate included yieldloss caused by 5% diamondback moth was estimated US$4 billion-US$5 billion. P. xylostella was managed by chemicalinsecticide such as organophosphates, carbamates and pyrethroids. But insecticide resistance which is caused by repeatedapplication makes it difficult to control this pest. For environmental friendly control of diamondback moth, entomopathogenicfungi could be used as alternative. We conducted bioassay to select high virulent isolate to larva of diamondback mothwith forty six entomopathogenic fungi which were isolated from soil samples by insect-bait method. As a result of bioassaytwelve isolates was selected as candidate. We investigated control efficacy of these twelve isolates with potted Chinesecabbage at laboratory and greenhouse.
        48.
        2017.10 구독 인증기관·개인회원 무료
        Among two different acetylcholinesterase (AmAChE1 and AmAChE2) of the western honey bee, the soluble AmAChE1might be related with a stress response as judged from its over-expression in honey bee workers when brood rearingwas suppressed. In this study, to ensure the nature of AmAChE1 responding to stress factors, the expression patternsof AmAChE1 were investigated following various treatments, including varroa mite infestation, bacterial challenge, broodrearing suppression, thermal stresses, chemical treatments, ultraviolet B irradiation, starvation, water restriction and crowdingstress. In addition, transcription profiles of four heat shock protein genes known as general stress markers and vitellogeningene, which is induced in several stress conditions, were tested as positive references. In every tested condition, onlybrood rearing suppression and heat shock were related with the expression of AmAChE1.
        49.
        2017.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The organic light-emitting diodes are fabricated with six anthracene derivatives containing simple substituents such as phenyl or naphthyl group. The device structure is as in the following: Indium tin oxide (ITO) (180 nm)/4,4-4,4`,4``-tris[N-(1-naphthyl)-Nphenylamino] triphenylamine (2-TNATA) (30 nm)/4,4`-bis[N-(1-naphthyl)-N-phenyl-1-amino] biphenyl (NPB) (20 nm)/Emitting compound (30 nm)/2,2′,2"- (1,3,5-Benzinetriyl)-tris (1-phenyl-1-H–benz-imidazole) TPBi (40 nm)/lithium quinolate (Liq) (2 nm)/Al (100 nm). In the emitting layer the anthracene derivatives are used without any dopant. All the six devices show blue emissions. Among the tested diodes, the one with 9-(2-naphthyl)-10-(p-tolyl) anthracene (2-NTA) exhibited luminous efficiency, power and external quantum efficiencies of 3.26 cd/A, 0.98 lm/A, 2.8 % at 20 mA/cm .
        4,000원
        51.
        2017.04 구독 인증기관·개인회원 무료
        Honey bee swarming is a natural phenomenon that occurs by changes of colony (i.e. population size and queen condition) and environment conditions. As cuticular hydrocarbons (CHCs) are known to be involved in the communication between honey bee nest-mates, we investigated and compared the CHC profiles of worker bees from individual colonies of 9-days before swarming (PPSC), a day before swarming (PSC), swarming (SG) and remaining (non-swarming) (RG). A total of 53 CHCs were identified by GC-MS, among which 11 compounds showed significantly differential expression patterns between swarming states. Before swarming (between PPSC and PSC), detection levels of 4 CHCs were significantly different, suggesting that production of some CHCs changed prior to swarming for swarming preparation. Six CHCs were deferentially produced between PSC and RG. The differential profiles of CHCs with respect to different swarming states are currently under investigation.
        52.
        2017.04 구독 인증기관·개인회원 무료
        There are two different types of acetylcholinesterase (AChE1 and AChE2) in the western honeybee as in most of insects. It is suggested that soluble AmAChE1 might be related with a stress response as judged from its elevated expression level in honey bee workers when brood rearing was suppressed. In this study, to ensure the nature of AmAChE1 responding to stress factors, the expression patterns of AmAChE1 following heat shock, brood rearing suppression and chemical treatments (Imidacloprid and fluvalinate) were investigated. Also, several heat shock protein (hsp) genes (hsp10, hsp60, hsp70 and hsp90) known as general stress markers were tested as positive references. Heat shock induced expression of every tested hsp along with AmAChE1. In brood rearing-suppressed worker bees, 7 days old bees showed much higher expression level of AmAChE1 and hsp90 compared to control honey bees. However, treatment of imidacloprid and fluvalinate did not induce any apparent overexpression of these genes. These results confirm that both HSP and AmAChE1 genes generally respond to temperature and brood rearing suppression and further suggest that AmAChE1 can serve as a potential biomarker along with hsps for the detection of stress in honey bee colonies.
        53.
        2017.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Anthracene has been a motive molecule for the blue-emitting materials in OLED. Since the blue emission needs big band gap between HOMO and LUMO, the blue-emitting materials are rare. In this paper, some anthracene derivatives containing simple aryl groups are synthesized and characterized. Regardless of the substituents the absorption and the emission bands are similar to each other and similar to the derivatives with the bulky silyl groups. The thermal and the CIE tests imply that among the tested 9-(2-naphthyl)-10-phenylanthracene is most promising for the diode. The material for the emission layer has to be investigated, which is simple to be prepared as well as good in the electrical and the thermal properties.
        4,000원
        54.
        2016.10 구독 인증기관·개인회원 무료
        Cotton aphid, Aphis gossypii Gloever is one of the major pests on a wide range of economically important crops in the world. The sustained use of chemical insecticides to control the aphid has led to the emergence of resistant strains to numerous used insecticides. As an alternative strategy entomopathogenic fungi have been used as part of integrated pest management program to control aphid, especially insecticide-resistance population. In particular, Beauveria bassiana-based commercial bio-insecticide has been used to reduce the pest population under greenhouse conditions in various countries. In this study, we investigated the control efficacy of a prototype of commercial mycopesticide using an B. bassiana (wettable powder) against cotton aphid on potted cucumber plant in greenhouse conditions.
        55.
        2016.10 구독 인증기관·개인회원 무료
        Two different types of acetylcholinesterae (AChE1 and AChE2) are present in majority of insects, including the Western honey bee. Out of the two honey bee AChEs (AmAChEs), the soluble AmAChE1 with little catalytic activity is widely distributed in both neuronal and non-neuronal tissues, including fat body. In this study, to identify stresss factors that can induce AmAChE expression, we tested various conditions that honey bees can encounter in natural setting, including heat shock, cold shock, bacterial challenge (Escherichia coli and Staphylococcus aureus) and Varroa mite infestations, and evaluated their effects on AmAChE expression. Among the stress factors tested, only heat shock condition induced AmAChE expression in a dose dependet manner. This finding suggests that one function of AmAChE1 is related with thermoregulations, especially against heat shock stress in honey bees.
        56.
        2016.10 구독 인증기관·개인회원 무료
        Honey bee swarming is a natural phenomenon that occurs when the colony encounters changes in the in-hive (i.e. population size and queen condition) and environmental conditions. To better understand the molecular basis of swarming, we conducted the transcriptomic profiles of worker bees between before swarming [pre-swarming colony (PSC)] and after swarming [swarming group (SG) and remaining group (RG)]. Based on the gene set enrichment analysis (GSEA), we predicted the biological processes associated with swarming. In addition, we analyzed the composition of cuticular hydrocarbons (CHCs) by gas chromatography-mass spectrometry and compared their profiles between different bee groups. GSEA results showed that there were a little differences between PSC and RG while many of the pathways related with metabolism and protein processing were down regulated in SG relative to PSC and RG. CHCs profiling revealed a similar CHCs composition between PSC and RG but some differences in CHCs composition (i.e. heneicosane, octacosane, octacosanol) were detected between SG and RG. These differences in gene pathway and CHC composition were discussed with respect to physiological changes and social communication.
        57.
        2016.10 구독 인증기관·개인회원 무료
        Acetylcholinesterase (AChE) is an enzyme for hydrolyzing neurotransmitter acetylcholine. Soluble form of AChE is generated via alternative splicing and functions as a bioscavenger in Dropsophila melanogaster. In this study, effects of ethanol and acetic acid on the soluble AChE expression were investigated. Treatment of ethanol and acetic acid results in over-expression of soluble AChE in the abdomen in a dose-dependent manner. However, no apparent change in AChE expression was observed in the head. Our finding suggests that the soluble AChE is involved in chemical defense against high concentration of ethanol, which is a common by-product from fermented food,and acetic acid, the main metabolite of ethanol. Thus, high level of ethanol and acetic acid resistance in D. melanogaster appears to be evolved via the induction mechanism of soluble AChE expression.
        58.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Even though klotho deficiency in mice exhibits multiple aging-like phenotypes, studies using large animal models such as pigs, which have many similarities to humans, have been limited due to the absence of cell lines or animal models. The objective of this study was to generate homozygous klotho knockout porcine cell lines and cloned embryos. A CRISPR sgRNA specific for the klotho gene was designed and sgRNA (targeting exon 3 of klotho) and Cas9 RNPs were transfected into porcine fibroblasts. The transfected fibroblasts were then used for single cell colony formation and 9 single cell–derived colonies were established. In a T7 endonuclease I mutation assay, 5 colonies (#3, #4, #5, #7 and #9) were confirmed as mutated. These 5 colonies were subsequently analyzed by deep sequencing for determination of homozygous mutated colonies and 4 (#3, #4, #5 and #9) from 5 colonies contained homozygous modifications. Somatic cell nuclear transfer was performed to generate homozygous klotho knockout cloned embryos by using one homozygous mutation colony (#9); the cleavage and blastocyst formation rates were 72.0% and 8.3%, respectively. Two cloned embryos derived from a homozygous klotho knockout cell line (#9) were subjected to deep sequencing and they showed the same mutation pattern as the donor cell line. In conclusion, we produced homozygous klotho knockout porcine embryos cloned from genome-edited porcine fibroblasts.
        4,000원
        59.
        2016.04 구독 인증기관·개인회원 무료
        Various insect pests and plant disease can outbreak in a field. For the effective control of pests and plant diseases during crop cultivation, farmers simultaneously or sequentially spray various eco-friendly agricultural materials (EFAM), chemical pesticides and microbial control agents on the same fields. It was reported that many agrochemicals are harmful to entomopathogenic fungi, especially some fungicides with broad spectrum activity that are routinely applied for the control of plant diseases. In addition, some pesticides may antagonize the potential insecticidal activity and efficiency of entomopathogenic fungi. Therefore, sometimes the utilization of fungal entomopathogen in forestry and agricultural production is limited because of the undesirable interference from some fungicides and pesticides. There is little research that examines the compatibility of these EFAMs with entomopathogenic fungi and the influence of EFAMs on the control efficacy of mycopesticides. We conducted a study of influence of pretreated eco-friendly agricultural materials on control efficacy of Isaria javanica isolate against sweet potato whitefly.
        60.
        2016.04 구독 인증기관·개인회원 무료
        Entomopathogenic fungus is a useful control agent to sucking type insect such as whitefly and aphid. The fungi are influenced by some environmental factors such as relative humidity, temperature and UV and cause slow and fluctuation in pest control efficacy. Especially, UV kills conidia or spores of entomopathogenic fungi and a mycopesticide using fungi has short control period in field. UV intensity changes from season to season. Survival rate of entomopathognic fungi treated may differ from seasons and will show different control efficacy. Therefore, we conducted a study to estimate the persistence of an Isaria javanica isolate, which was already reported as sweet potato whitefly control agent, in potted greenhouse soil planted different crops. The number of survival spore decreased gradually and differ from seasons.
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