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        검색결과 3,117

        1061.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Dyes are widely used in various industries including textile, cosmetic, paper, plastics, rubber, and coating, and their discharge into waterways causes serious environmental and health problems. Four different carbon nanostructures, graphene oxide, oxidized multi-walled carbon nanotubes, activated carbon and multi-walled carbon nanotubes, were used as adsorbents for the removal of Nile Blue A (NBA) dye from aqueous solution. The four carbon nanostructures were characterized by scanning electron microscope and X-ray diffractometer. The effects of various parameters were investigated. Kinetic adsorption data were analyzed using the first-order model and the pseudo-second-order model. The regression results showed that the adsorption kinetics were more accurately represented by the pseudo-second-order model. The equilibrium data for the aqueous solutions were fitted to Langmuir and Freundlich isotherms, and the equilibrium adsorption of NBA was best described by the Langmuir isotherm model. This is the first research on the removal of dye using four carbon nanostructures adsorbents.
        4,000원
        1062.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This paper introduces a nitrogen-doped ordered mesoporous carbon (NOMC) derived from glucosamine with hybrid capacitive behaviors, achieved by successfully combining electrical double-layer capacitance with pseudo-capacitance behaviors. The nitrogen doping content of the fabricated NOMC reached 7.4 at% while its specific surface area (SBET) and total pore volume reached 778 m2 g−1 and 1.17 cm3 g−1, respectively. A dual mesoporous structure with small mesopores centered at 3.6 nm and large mesopores centered at 9.9 nm was observed. The specific capacitance of the reported materials reached up to 328 F g−1, which was 2.1 times higher than that of pristine CMK-3. The capacitance retention rate was found to be higher than 87.9% after 1000 charge/discharge cycles. The supplementary pseudocapacitance as well as the enhanced wettability and conductivity due to the incorporation of nitrogen heteroatoms within the carbon matrixes were found to be responsible for the excellent capacitive performance of the reported NOMC materials.
        4,000원
        1063.
        2017.06 구독 인증기관 무료, 개인회원 유료
        This study investigated the relationship between class size and students’ participation on the academic performance of senior secondary school students in Nigeria. The population for this study comprised all the Senior Secondary school students in Mainland Local Government Area, Lagos State. The study adopted descriptive survey design and random sampling technique was used in arriving at the selection of two hundred and seventy (270) students and thirty (30) teachers among the population of senior secondary school students in Mainland Local Government Area in Lagos State, which formed the sample of this study. Specifically, students and teachers were randomly selected from six Senior Secondary schools in Mainland Local Government in Lagos State. Forty five (45) Senior Secondary school students and five (5) teachers were randomly sampled from each school. Two self- developed, structured and validated questionnaires (students’ questionnaire and teachers’ questionnaire) of 15 items for teachers’ questionnaire and 18 items for students’ questionnaire were used to collect information from the students and teachers after its validity and reliability were determined. The data collected were analyzed using mean, standard deviation, simple percentage while Pearson Product Moment Correlation Coefficient statistical tool was used for hypothesis testing at 0.05 levels of significance. The study revealed that: there is no significant relationship between class size and academic performance. There is significant difference between the students’ participation and their academics performance in secondary schools. There is no significance relationship between students’ perception of class size and the academic performance. There is no significance relationship between teachers’ perception of class size and the students’ academic performance.
        4,800원
        1064.
        2017.05 구독 인증기관·개인회원 무료
        Ganglioside GT1b, glycosphigolipids with three sialic acid, is known to play an important role in signal transduction such as epidermal growth factor receptor (EGFR). EGF is also known to induce resumption of meiosis and cumulus cells expansion during porcine oocyte maturation. Therefore, this study was conducted to evaluate the effects of ganglioside GT1b on resumption of meiosis and cumulus cells expansion in porcine oocyte maturation. First, porcine cumulus-oocyte complexes were cultured in NCSU-23 medium supplemented with GT1b (0, 1, 2 and 4 μM) at 44 h. We observed that the proportion of the metaphase II (M II) stage was significantly increased in the 2 μM GT1b (78.0 ± 2.3) treated group than in the other groups. Furthermore, expression of cumulus cells expansion factor genes (Has2, TNFAIP6, Ptx3) were significantly increased in the 2 μM GT1b treated group than in the other groups. Next, we investigated the meiotic maturation and the expressions of cumulus cells expansion factor genes after GT1b and/or EGF treatment. The proportion of the M II stage was significantly higher in the GT1b+EGF (90.1 ± 2.3) treated group than in the other groups. Moreover, expressions of cumulus cells expansion factor genes were significantly increased in the GT1b+EGF treated group than in the control group. After in vitro fertilization, fertilization rate, preimplantation development competence and quality of blastocyst were improved in oocytes derived from GT1b+EGF treated group. Taken together, these results suggest that exogenous ganglioside GT1b improving the developmental competence of porcine embryos via increase of resumption of meiosis and cumulus cells expansion during in vitro maturation of porcine oocytes.
        1065.
        2017.04 구독 인증기관·개인회원 무료
        With increasing interests on health issues, whole grains are getting focus with their various beneficial effects along with unique characteristics. Studies on whole grains, however, are mostly focused on whole wheat grains, no systematic researches on whole rice grain has been attempted. In this study, we tried to characterize the starches in whole rice grain including morphology, molecular weight distribution and its side chain structures for further application. Early harvested whole rice grains, named as green whole rice (GWR) was coarsely grounded and starch fraction was separated through alkaline steeping method and dried for the analysis. Morphology of starch particles of GWR was investigated with scanning electron microscopy (SEM) and no significant differences was observed compared to the control rice starches. Pre-treatments such as dehulling and steaming also did not affect overall shape of starches in rice. Molecular weight distribution of GWR starch was analyzed with gel permeation chromatography (GPC) and compared with normal rice starch. GPC analyses revealed that the relative ratio of higher molecular weight fractions in GWR was significantly higher than normal rice. In addition, side chain structures of amylopectin molecules in GWR starch was analyzed with high performance size exclusion chromatography (HPSEC). The average number of DP in GWR was shorter with higher ratio of shorter side chain fractions than normal rice starch. These findings on GWR starch would be useful basement for following research and application of green whole rice.
        1066.
        2017.04 구독 인증기관 무료, 개인회원 유료
        Cryptography is a science to maintain the security of the message by changing data or information into a different form, so the message cannot be recognized. Today, many algorithms have been proposed for image encryption, but the chaotic encryption methods have a good combination of speed and high security. In recent years, the chaos based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques. The chaos-based encryption schemes are composed of two steps: chaotic confusion and pixel diffusion. In the chaotic confusion stage, a combination of the chaotic maps is used to realize the confusion of all pixels. In this paper, we first give a brief introduction into chaotic image encryption and then we investigate some important properties and behaviour of the logistic map. The logistic map, aperiodic trajectory, or random-like fluctuation, could not be obtained with some choice of initial condition. Therefore, a noisy logistic map with an additive system noise is introduced. The proposed scheme is based on the extended map of the Clifford strange attractor, where each dimension has a specific role in the encryption process. Two dimensions are used for pixel permutation and the third dimension is used for pixel diffusion. In order to optimize the Clifford encryption system we increase the space key by using the noisy logistic map and a novel encryption scheme based on the Clifford attractor and the noisy logistic map for secure transfer images is proposed. This algorithm consists of two parts: the noisy logistic map shuffle of the pixel position and the pixel value. We use times for shuffling the pixel position and value then we generate the new pixel position and value by the Clifford system. To illustrate the efficiency of the proposed scheme, various types of security analysis are tested. It can be concluded that the proposed image encryption system is a suitable choice for practical applications.
        4,200원
        1068.
        2017.04 구독 인증기관·개인회원 무료
        1069.
        2017.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The aim of the work was to investigate the thermo-electrical properties of low cost and rapidly produced randomly oriented carbon/carbon (C/C) composite. The composite body was fabricated by combining the high-pressure hot-pressing (HP) method with the lowpressure impregnation thermosetting carbonization (ITC) method. After the ITC method step selected samples were graphitized at 3000°C. Detailed characterization of the samples’ physical properties and thermal properties, including thermal diffusivity, thermal conductivity, specific heat and coefficient of thermal expansion, was carried out. Additionally, direct current (DC) electrical conductivity in both the in-plane and through-plane directions was evaluated. The results indicated that after graphitization the specimens had excellent carbon purity (99.9 %) as compared to that after carbonization (98.1). The results further showed an increasing trend in thermal conductivity with temperature for the carbonized samples and a decreasing trend in thermal conductivity with temperature for graphitized samples. The influence of the thickness of the test specimen on the thermal conductivity was found to be negligible. Further, all of the specimens after graphitization displayed an enormous increase in electrical conductivity (from 190 to 565 and 595 to 1180 S/cm in the through-plane and in-plane directions, respectively).
        4,200원
        1070.
        2017.04 구독 인증기관·개인회원 무료
        Monochamus alternatus (M. alternatus) and Monochamus saltuarius (M. saltuarius) are major vectors for Bursaphelenchus xylophilus in South Korea. When an adult, they are easily distinguishable by several morphological classification. However, it is difficult to identification between M. alternatus and M. saltuarius when they are larvae as they have very similar morphological characters. Thus, they are not easily distinguishable without expertise about Cerambycidae taxonomy. Furthermore, during epidemiological investigation, sometimes, adults or larvae would not be founded in death pine trees. For these reasons, in this experiment, we are able to identified between M. alternatus and M. saltuarius by mitochondrial 12S rRNA gene primers that are specific to 12S rRNA gene fragment of M. alternatus using larvae tissue and frass. Moreover, we had examined whether vectors that were already escaped from dead pine tree have Bursaphelenchus xylophilus or not by multiplex PCR using larva frass that was remained in dead pine tree.
        1071.
        2017.04 구독 인증기관·개인회원 무료
        Monochamus alternatus (M. alternatus) and Monochamus saltuarius (M. saltuarius) are major vectors for Bursaphelenchus xylophilus in South Korea. When an adult, they are easily distinguishable by several morphological classification. However, it is difficult to identification between M. alternatus and M. saltuarius when they are larvae as they have very similar morphological characters. Thus, they are not easily distinguishable without expertise about Cerambycidae taxonomy. Furthermore, during epidemiological investigation, sometimes, adults or larvae would not be founded in death pine trees. For these reasons, in this experiment, we are able to identified between M. alternatus and M. saltuarius by mitochondrial 12S rRNA gene primers that are specific to 12S rRNA gene fragment of M. alternatus using larvae tissue and frass. Moreover, we had examined whether vectors that were already escaped from dead pine tree have Bursaphelenchus xylophilus or not by multiplex PCR using larva frass that was remained in dead pine tree.
        1072.
        2017.04 구독 인증기관·개인회원 무료
        콩명나방(Maruca vitrata)은 팥과 동부를 포함하는 Vigna 속 작물을 가해하는 해충이다. 다양한 화학 살충제가 이 해충의 유충을 방제하는 데 효과적이다. 특히 Bacillus thuringiensis (Bt) 미생물농약이 이 해충을 방제하는 데 가능성을 제시하였다. 그러나 화학농약에 비해서 비교적 느린 살충 효과는 현장 적용에 어려움을 주었다. 본 연구는 Bt의 살충효과를 증가시키기 위해 면역억제제를 첨가하는 방안을 강구하였다. 콩명나방의 면역반응은 혈구세포의 소낭형성으로 분석하였다. 소낭형성 반응은 아이코사노이드 생합성 억제자인 dexamethasone 처리에 의해 현격하게 낮아졌다. 아이코사노이드 생합성 억제자를 합성하여 분비하는 Xenorhabdus nematophila 세균 배양액을 Bt와 함께 처리한 결과 Bt 단독에 비해 살충효과가 크게 증가하였다. 본 연구는 비티플러스 살충제가 콩명나방 방제에 효과적이라 는 것을 제시하였다.
        1073.
        2017.04 구독 인증기관·개인회원 무료
        It has been proved that agroinfiltration-based temporary expression of coatomer subunit alpha (COPA) gene from Tetranychus urticae hairpin RNA induces RNA interference (RNAi) and lethality to T. urticae. To establish detailed protocols for agroinfiltration, the efficiency of agroinfiltration to the soybean and kidney bean was determined with respect to different Agrobacterium delivery methods (sea sand, carborundum and syringe) and the spacial expression patterns of hairpin RNA was investigated following Agrobacterium delivery. Sea sand and syringe showed the highest expression level in soybean and kidney bean, respectively. Considering the resulting tissue damage, syringe appeared the best choice for agroinfiltration in both soybean and kidney bean. The apical region of a leaf showed more relative expression levels in both soybean and kidney bean compared to the basal region. Following agroinfiltration, adjacent untreated leaves were determined to express hairpin RNA though the expression level was low, suggesting that hairpin RNA can be translocated to other leaves. In conclusion, Agrobacterium delivery by syringe and use of whole leaf were recommended for T. urticae bioassay following agroinfiltration.
        1074.
        2017.04 구독 인증기관·개인회원 무료
        Metabolic resistance mechanisms of Laodelphax striatella to several insecticides, such as neonicotinoids, organophosphates and pyrethroids, have been investigated by evaluating the transcription levels of CYP450 genes. Nevertheless, no study on the CYP450-mediated carbamate resistance in L. striatella has been conducted to date. Here, we determined the transcription levels of six CYP450 genes and one carboxylesterase gene to screen detoxification genes associated with carbamate resistance. The CYP6CW1 exhibited the highest transcription level (18 fold) in a resistance strain. Interestingly, its transcription level increased slightly (3 fold) in a susceptible strain upon the exposure to a sublethal dose (LC30) of carbofuran. These results suggest that CYP6CW1 expression is inducible by carbofuran and its overexpression is likely responsible for carbofuran tolerance and resistance in L. striatella.
        1075.
        2017.04 구독 인증기관·개인회원 무료
        To identify genes that commonly respond to the treatment of different insecticides, 3rd instar larvae of the diamondback moth, Plutella xylostella, were treated with sublethal doses (<LC10) of chlorantraniliprole, cypermethrin, dinotefuran, indoxacarb and spinosad via leaf dipping. Then, transcriptomic profiles of treated larvae were compared with that of untreated control. A total of 117,181 transcripts in average with a mean length of 662 bp were generated by de novo assembly, of which 35,329 transcripts were annotated. Among them, 207, 153, 336, 360, and 262 transcripts were determined to be up-regulated whereas 117, 47, 92, 115, and 81 genes were down-regulated following treatments with chlorantraniliprole, cypermethrin, dinotefuran, indoxacarb and spinosad, respectively. Finally, with the criteria of >10 X fold change (FC) and p < 0.05 or >4 X FC, p < 0.05 and q < 0.2, the genes commonly over-transcribed in all treated insects were selected and their over-transcription levels were confirmed by quantitative PCR. These commonly responding genes included three cytochrome P450 genes (Cyp303a1, Cyp6a20 and CYP9E2), three cuticle protein genes (LM-8, LM-19 and TM-A3A), lavesin-1, acyl-CoA D11 desaturase, glucose dehydrogenase, nose resistant to fluxetine protein 6, chorion peroxidase and protein yellow. As the five test insecticides have distinct structure and mode of action, the genes identified in this study were suggested to be involved in general chemical defense at the initial stage of intoxication. Their possible roles in tolerance and resistance development were further discussed.
        1076.
        2017.04 구독 인증기관·개인회원 무료
        Aphidiinae in Braconidae includes more than 400 species within approximately 60 genera worldwide. Species of Aphidiinae are mostly known as solitary koinobiont endoparasitoids specifically associated with aphid hosts, and some of them are used for biological control. In the present study, two aphiniine species are newly recognized from South Korea based on morphological and molecular study: Aphidius rhopalosiphi de Stefani-Perez 1902 and A. uzbekistanicus Luzhetzki 1960. Although It was very difficult to discriminate two species morphologically, we cleary identified them by using COI (cytochrome c oxidase subunit I) DNA Barcode sequences. Here we present their morphological descriptions, illustrations and barcoding results.
        1077.
        2017.04 구독 인증기관·개인회원 무료
        Swarming alates of termite Macrotermes sp. has been accepted as food among people of Benishangul Gumuz zone in west Ethiopia bordering with Sudan. The preference seems to be for the reproductive caste. We assessed the nutritional composition of nymph and alate of Macrotermes sp. of Ethiopia. The adult contained higher amino acids (31%) compared to nymph (21%). However, the distribution of amino acids in the protein was similar (ap. 4:6 essential to non-essential amino acids). Both stages tend to have high fat contents (50%). Fat supplement could be a possible reason behind the human consumption of termites. Beside the bio-prospection of termite as food or oil source, termite foraging would have important evolutionary biology due to their significant amount of energy-yielding nutrients which could presumably be critical resource for development of larger brained hominines.
        1078.
        2017.04 구독 인증기관·개인회원 무료
        Nitric oxide (NO) is an immune mediator in several insects. In addition, eicosanoids mediate various immune responses in response to microbial challenges. This study focuses on cross-talk between two immune mediators. Nitric oxide synthase (SeNOS) of Spodoptera exigua was predicted in its cDNA sequence by interrogation to the transcriptomes and validated by RT-PCR against developmental stage and larval tissues. RNA interference (RNAi) of SeNOS suppressed nodule formation of S. exigua larvae against heat-killed Xenorhabdus hominickii. RNAi of SeNOS also suppressed NO levels in fat body and hemocytes along with suppression of PLA2 activity. NOS-specific inhibitor, L-NAME, also inhibited PLA2 activity, but its enantiomer, D-NAME, did not. However, PLA2 of dexamethasone or oxindole did not suppress NO levels in the immune tissues. In addition, X hominickii did not inhibit up-regulation of NO levels. These results suggest that NO signal activates PLA2 to produce eicosanoids to mediate immune responses
        1079.
        2017.04 구독 인증기관·개인회원 무료
        Rapid resistance detection of resistance level is most important step to manage the resistant population in Tetranychus urticae in Korea. Residual contact vial bioassay (RCV) and quantitative sequencing (QS) methods were employed to determine the resistance level and applied to measure the resistance level of 46 field population collected from rose, strawberry and apple trees. Most populations exhibited multiple resistance pattern to various types of acaricides. Especially, the resistance levels in mites from rose cultivation area were higher than those from strawberry and apple cultivation areas. The resistance level detection would provide a useful parameter enabling the proactive action for a proper resistant population management for T. urticae.
        1080.
        2017.04 구독 인증기관·개인회원 무료
        Ryanodine receptors (RyRs) regulate the contractions of insect muscles by altering intracellular Ca2+ concentration and are the targets of chlorantraniliprole. Here we established two resistant strains of Drosophila melanogaster, which were treated with low or high concentrations of chlorantraniliprole, and their resistance levels were determined on the basis of contact and ingestion toxicities. Compared with the wild type, the two resistant strains did not show any significant differences in contact toxicity. However, they showed significantly increased resistance ratios in ingestion toxicity than that by the wild type. The resistant strains had altered expression levels of RyRs and more enhanced Acetylcholinesterase and Glutathione-S-transferase activities than that by the non-selected strain. These results suggested that the resistance development of chlorantraniliprole in the two strains might be mediated by the activation of detoxification pathways in D. melanogaster.