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        검색결과 126

        23.
        2018.10 구독 인증기관·개인회원 무료
        A total of 53 nontarget species representing six orders of insects were captured in the codling moth surveillance traps placed in Korea over the last eight years. These included 20 species (37.7%) of moths (Lepidoptera) belonging to 9 families of which 9 species were tortricids, 12 species (22.6%) of beetles (Coleoptera) belonging to 10 families, 11 species (20.8%) of flies (Diptera) belonging to 7 families; 4 families of true bugs (Hemiptera) including one species of Anthocoridae (9.4%); 1 family of Hymenoptera including 2 species of Formicidae (3.8%) and 1 family of Neuroptera including 3 species of Chrysopidae (5.7%). A list of the species of nontarget insects captured in the codling moth surveillance traps is provided. A brief diagnosis and photographs of Aterpia issikii Kawabe, the tortricid moth newly documented in Korea are provided.
        24.
        2018.07 구독 인증기관 무료, 개인회원 유료
        The young generation that was born in the digital age grew up with digital technologies; they listen to music online on web sites like YouTube, which provides access to music by artists from all over the world. We conducted a functional near-infrared spectroscopy (fNIRS) experiment with fifty-six young adults. The human brain generates electrical waves as long as it lives. Since the dynamic nature of brain rhythm is at work in all kinds of human brain function, neuroscientists have used brain rhythm to understand brain function. Since the work of Gerstein and Mandelbrot (1964), many attempts have been made to use random-walk analyses to account for brain responses like the spiking of neurons, cell migration, and motor variability. Like any other biological system, the brain pursues functional efficiency at all levels of operation—in the brain’s case, from the neuronal cell level to the neural network level. Before one can determine the presence of a periodic rhythm versus a random state in brain activation, one must determine whether external stimuli can shape the brain’s modulation pattern. Brain-wave patterns are affected by whether the neural circuit that governs a particular set of brain functions reaches a significant level of activation. The bottom-up processing of external stimuli can be affected by top-down processing; in other words, the execution of higher-order cognitive attention can affect the degree of randomness in the bottom-up processing of external sensory inputs like that of music. Unlike EEG signals, the rhythms of hemodynamic signals are not commonly calculated, possibly because hemodynamic signals are sluggish. The random-walk test on neural time series has been applied only recently to magnetoencephalography (MEG) data (Kipiński, König, Sielużycki, & Kordecki, 2011), and it has rarely been applied to hemodynamic signals measured with magnetic resonance imaging (MRI) or near-infrared spectroscopy (NIRS). However, since hemodynamic responses are the result of neurovascular coupling—a dynamic event among the brain’s neurons, glias, and vasculatures—it is possible to calculate the degree of randomness of hemodynamic signals as surrogates for neuronal activity. While brain activities are inherently random and noisy in their natural state, when the brain rhythm is modified by music that provides appropriate levels of sensory stimulation, the brain’s signals will begin to reflect the music’s rhythms. This reflection is called “attunement.” The effect of sensori-neural stimulation on hemodynamic responses measured by fNIRS has been reported in neuroscience research that found that auditory stimulation and music elevated the concentrations of oxygenated hemoglobin (HbO2) and total hemoglobin (HbT) in blood flow to certain regions of the brain (Hoshi & Tamura, 1993; Kotilahti et al., 2010; Sakatani, Chen, Lichty, Zuo, & Wang, 1999). However, studies have shown decreases (increases) in children’s (adults’) prefrontal cerebral volume after they play computer games. For example, one study suggested that the level of attention may modulate the directional changes in HbO2 and HbT concentrations (Nagamitsu, Nagano, Yamashita, Takashima, & Matsuishi, 2006). The brains of children who find that a game lacks adequate levels of perceptual stimulation do not require an additional supply of oxygen, but adults who find playing the same game a cognitive challenge require more effort to perform the same task, so they require elevated levels of oxygen in their brains (Ferreri et al., 2014). According to musical theorists, when the brain is entrained, the attention follows the music (London, 2012). When members of the digital generation listen to music, the perceptual stimulation level is likely to related to the degree of randomness in brain responses as well as the quality of the sensory experience. Drawing on the literature review, we predict that TBF is higher for a stimulus that is above OSL than the TBF for a counterpart stimulus that is below OSL. We also predict that the hemodynamic rhythm of related brain regions to music that is above OSL adopts a regular predictable pattern. Hence, we propose the following research hypotheses: H1: Digital music that provides acoustic stimulation near the OSL creates brain responses in the form of higher TBF and lower randomness in HbO2 concentrations than does digital music that provides acoustic stimulation that is below the OSL. Functional Near-infrared Spectroscopy The transparency of biological tissue to light in the near-infrared wavelengths makes NIRS possible. NIRS is non-invasive and portable, and it has a cost advantage. The incident near-infrared light from a transmitting optode (source) is scattered through the tissues, and the reflected light is detected by a receiving optode (detector). The amount of the source light that a tissue absorbs depends on the light’s wave length, and the oxygenation status determines the brain’s absorption of the light. The loss of the intensity that is due to the absorption of the photons can be measured in units of optical density (Zaramella et al., 2001). The changes in [oxy-Hb] and [deoxy-Hb] can be calculated according to the modified Beer-Lambert law (Kocsis, Herman, & Eke, 2006) using two wave lengths of near-infrared light—in our case, 780 and 850nm. We used a 12-channel wireless fNIRS system (Biomedical Optics Lab, Korea University) with sampling rates of 8 ~10 Hz to measure the participants’ hemodynamic response while they watched the videos. The system consists of three light sources and five detectors (a 3×7 grid). The fNIRS probe was attached to each subject’s forehead. The detectors of the lowest line were set along the Fp1 and Fp2 electrode line according to the international 10/20 system. Measurements from channels 1, 2, 11, and 12, which contained noise from movements of the subjects’ heads, hair, and sweat, were excluded from further analysis. Neuroscience research has recorded acoustic stimulation in various regions of the brain, including the temporal brains of newborn babies (Hoshi & Tamura, 1993) and the frontal brains of adults (Sakatani et al., 1999). Since infrared light cannot penetrate hair, brain regions that are not covered by hair, such as the prefrontal cortex, are well-suited to an fNIRS study. When a member of the digital generation listens to music online, the motivation is usually enjoyment, so brain activity changes that are due to popular music should occur in brain areas that are associated with reward-related processing—that is, the medial pre-frontal cortex (mPFC) (Haber & Knutson, 2010). As the mental function of pleasurable experience that is modulated in the medial frontal cortex increases, TBF to this region increases. In particular, the processing of sounds is dominantly modulated by the brain’s right hemisphere (Kaiser, Lutzenberger, Preissl, Ackermann, & Birbaumer, 2000). We analyzed TBF to the right brain area of the mPFC at channel 5 using fNIRS. The research hypothesis predicts that songs that provide strong sensory stimulation above the OSL increase the TBFs of those in the digital generation more than do songs that present a sensory stimulation level that is much under the OSL. TBF can be directly obtained as a product of HbT (Wyatt et al., 1990). After the music began in the experiment, the subjects’ concentrations of HbT increased until HbT reached its peak at around five to eight seconds; then it decreased for the next thirty seconds. There was a divide of hemodynamic responses between the two songs that had more than a million hits per day (A and B) and the remaining three (C, D, and E). We conducted repeated measures of ANOVA on TBF, measured at forty seconds, for the five songs, since TBF at the end of each set of song segments can represent the digital generation’s level of sustained attention. The multivariate test for the model was significant, and the main effect of songs on TBF was significant (Wilk’s Lambda 0.75, F(4,51)=4.249, p=0.005,  ). After the forty seconds of each song were over, the TBF levels remained at the highest level for song A, followed in order by Songs B, C, D, and E. Pairwise comparisons after the Bonferroni correction showed that there was a significant divide in the length of time that the TBF levels remained at the highest level between songs A/B and songs C/D/E (p<0.05). Other differences were not significant, possibly because the neural data contained large individual difference variances (between-subject F test: F(1,54) =38.501, .p<0.001, ). The results support hypothesis 1. Next, we examined the relationships between TBF and daily hits, and BORP and daily hits. The Pearson correlation coefficient between TBF and daily hits was 0.88 (p<0.05), and the correlation coefficient between BORP and daily hits was -0.96 (p<0.05). Pairwise comparisons after the Bonferroni correction showed that, there was a significant divide in the length of time that the TBF levels remained at the highest level between songs A/B and songs D/E (p<0.05). Other differences were not significant, possibly because neural data contains a large portion of individual variance (between-subject F test: F(1,54) =372.675, p<0.001,  ). These results are consistent with our hypothesis 1b that pop music that presents stimulation above OSL can reduce the randomness in hemodynamic signals. The changes in the participants’ hemoglobin concentrations while they listened to popular songs show a mean-reverting tendency with low BORP—a “rhythm” such that a system recovers order and balance in due time. The brain’s response to less popular songs were random-walk processes, which represents a neural drain, a process in which brain fails to recover from oxygen depletion because of boredom. In conclusion, we found that total blood flow to the right medial prefrontal cortex increased less when the young adults were exposed to music that presented acoustic stimulation near the optimal sensory load (OSL) than it did when they were exposed to songs with a level of stimulation much below the OSL. The degrees of hemodynamic randomness decreased significantly while the participants listened to online music that provided near-OSL stimulation. Online popularity, recorded as the number of daily hits, was significantly positively correlated with the total blood flow and negatively correlated with hemodynamic randomness. These findings suggest that a new digital media strategy may be required that provides a sufficient level of sensory stimulation as an essential part of marketing to the digital consumer generation.
        3,000원
        25.
        2016.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        인접 국가인 일본의 후쿠시마 원전에서 극한 자연재해로 인한 중대사고가 발생하면서, 국내에서 중대사고 및 확률론적 안전성 평가 (PSA, Probabilistic Safety Assessment)에 대한 중요성이 재인식되었다. 국내에서는 원전의 소외결말을 평가하는 3단계 PSA에 대한 연구개발이 최근까지 거의 이루어지지 않았다. 본 논문에서는 국외 3단계 PSA 전산코드 중, 미국의 MACCS2 (MELCORE Accident Consequence Code System 2), 유럽의 COSYMA (COde SYstem from Maria) 그리고 일본의 OSCAAR (Off-Site Consequence Analysis code for Atmospheric Releases in reactor accidents)에 대한 간략한 분석과 미국 의 MACCS2에 대한 단점 및 한계점 분석을 수행하였다. 국내·외 전문가들에 의해 공통적으로 지적되어 온 MACCS2의 한 계점은 다수호기사고와 사용후핵연료 저장조로부터의 방출 모사의 불가능, 그리고 대기확산모델을 단순 가우시안 플륨모델을 기본으로 한다는 것이며, 이중 일부는 MACCS2업데이트 버전을 통해 개선되어 왔다. Food chain 모델의 모사의 제한, 해양 및 수계 확산모델의 부재, 제한된 범위의 경제영향평가 등 또한 개선되어야 할 사항이다. 기술보고의 결과는 국내 3단 계 PSA 관련 기술 개발을 위한 기초자료로 활용될 수 있을 것으로 기대된다.
        4,300원
        26.
        2014.11 구독 인증기관·개인회원 무료
        Mushroom is cultivated as one of the major economical crops in many areas in Korea. The total production has steadily increased from approximately 198,563 M/T in 2009 to 208,941 M/T in 2012. Several fungus are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Trichoderma harzianum is the causal agent of brown blotch disease of commercial mushrooms. Colonization of mushroom caps by the bacterium results in development of brown or cream lesions on pileus and stipe. These lesions are slightly concave spots and can be round or spreading. Antagonists against Trichoderma harzianum, CAM33 were selected and their control efficacy of green mould disease was investigated in this study. The CAM33 strain was selected as antagonistic bacterium by inhibition zone method and it was identified as Bacillus methyrotrophicus. by the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA. The isolated bacterium is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacterium for Trichoderma harzianum cell, was sufficient for inhibition in vitro. Inoculation of the isolated bacterium prevents the development of bacterial disease in Trichoderma harzianum. Control efficacy of browning disease of strain CAM33 treatment was 77% on Agaricus bisporus. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 3.0% Saccharose, 1.5% Soytone, 1.0% (NH4)2HPO4, 10 mmol MgSO4, and 2.0% Glutamic acid at pH 6.0 at 25°C. The suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by Trichoderma harzianum.
        27.
        2014.11 구독 인증기관·개인회원 무료
        The button mushroom, Agaricus bisporus, is one of the major economical crops cultivated in Korea. This mushroom showed the 5th production to 10,996 M/T in 2012. Several fungus are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Cladobotryum mycophilum is the causal agent of cobweb disease of commercial mushrooms. Early symptoms were noticed as round, fleshy, yellowish brown lesions on mushroom caps. Late symptoms progressed when the parasitic fungus formed white cobweb circular colonies on dead or damaged pinheads, spread on the surface of the casing, and covered entirely fruiting bodies. A Gram-positive bacterium was isolated from mushroom media that markedly showed the antagonistic activity against Cladobotryum mycophilum, the most destructive pathogen of cultivated mushrooms. The HC7 strain was selected as antagonistic bacterium by inhibition zone method and it was identified as Bacillus altitudinis. by the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA. The isolated bacterium is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacterium for Cladobotryum mycophilum cell, was sufficient for inhibition in vitro. Inoculation of the isolated bacterium prevents the development of bacterial disease in Cladobotryum mycophilum. Control efficacy of browning disease of strain HC7 treatment was 78% on Agaricus bisporus. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 3% Soluble startch, 10% Soytone, 1% (NH4)2HPO4, 1 mmol KCl, and 0.5% L-asparagin at pH 6.0 at 30°C. The suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by Cladobotryum mycophilum.
        28.
        2014.06 구독 인증기관·개인회원 무료
        The button mushroom, Agaricus bisporus, is one of the major economical crops cultivated in Korea. This mushroom showed the 5th production to 10,996 M/T in 2012. Several bacteria are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Pseudomonas agarici is the causal agent of browning disease of commercial mushrooms. Colonization of mushroom caps by the bacterium results in development of browning lesions on pileus. These lesions are superficial brown spots and can be round or spreading. But P. agarici never caused sunken lesions and rotting of the mushroom tissues. A Gram-positive bacterium was isolated from mushroom media that markedly showed the antagonistic activity against Pseudomonas agarici, the most destructive pathogen of cultivated mushrooms. The HC42 strain was selected as antagonistic bacterium by inhibition zone method and it was identified as Bacillus safensis. by the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA.. The isolated bacterium is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacterium for P. agarici cell, was sufficient for inhibition in vitro. Inoculation of the isolated bacterium prevents the development of bacterial disease in Agaricus bisporus. Control efficacy of browning disease of strain HC42 treatment was 66% on Agaricus bisporus. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 1.5% D-galactose, 1.5% yest extract, 1% NH4Cl, 1.5% KCl, and 1.0% L-asparagin at pH 6.0 at 25℃. The suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by P. agarici.
        32.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to evaluate the nutritive value and the quality of ensiled kenaf after fermentation with three cultivars at three different times of harvesting. Experimental plot were allocated with three harvest date (Early;8/3, medium;8/15 and late;8/28) and three cultivars (Tainung-a, Everglade, Whitten). The DM (dry matter) yield increased with maturity in all three cultivars, especially in Whitten which showed the highest yield at each harvest time. The DM content in Whitten at late harvesting time was higher than other treatments (231 g kg 1DM). The CP (crude protein) contents of the kenaf silage of all three cultivars ranged from 151 to 164 g kg 1. Highest content of NDF (neutral detergent fiber) was observed in Everglade at medium harvesting date, but the ADF (acid detergent fiber) content was highest in Everglade at early harvesting date (p<0.05). All treatments produced a pH less than 4.0, which is sufficient for stable storage. The pH of Tainung-a was higher than other cultivars at all harvesting times (p<0.05). Whitten showed the higher content of lactic acid (25.8 g kg 1 DM) showed at early harvesting date than other cultivars (p<0.05), while the acetic acid content (21.1 g kg 1 DM) was higher in Tainung-a at medium harvesting date (p<0.05). No significant difference was observed in ammonia-Nand butyric acid concentrations among all treatments. These results indicate that a kenaf silage could be used as fodder for ruminants. Especially, the Whitten harvested at late growing stage showed promise as a forage silage crop under Koran environments.
        4,000원
        33.
        2012.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        원전이 위치한 동해 월성 연안역 주변에서 오염물 이동·확산에 대한 수치 모사를 수행하였다. 월성 연안역의 유속장 재현을 위한 해수유동 수치모형 실험은 EFDC(Environmental Fluid Dynamics Code) 모델을 사용하여 조위 시계열 검증 및 조화분석을 통한 검증을 실시한 결과 양호한 재현성을 나타내었다. 월성 주변해역의 유속장 산정 결과 창조류시에는 남향, 낙조류 시에는 북향으로 진행되는 결과를 알 수 있었다. 또한 국립수산과학원에서 관측한 수온, 염분의 자료를 이용하여 수치모델을 통한 계산값과 관측값을 비교한 결과 양호한 재현성을 나타내었다. 계산된 해수유동자료와 수온, 염분의 결과를 이용하여 오염물질의 확산특성을 해석하였다.
        4,000원
        34.
        2012.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        4,000원
        37.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        4,500원
        38.
        2011.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        4,200원
        39.
        2011.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        4,000원
        40.
        2011.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        4,200원
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