• The Korean Journal of Pesticide Science
• /
• v.4 no.4
• /
• pp.40-47
• /
• 2000

The comparative toxicity of ten acaricides, seven insecticides and five fungicides to the two-spotted spider mite, Tetranychus urticae and its predators, Amblyseius womersleyi and A. eharai was evaluated by a leaf spray bioassay. Five of the acaricides tested, bifenazate, etoxazole, acequinocyl, flufenoxuron and chlorfenapyr were much less toxic to adult females of A. womersleyi and A. eharai than to T. urticae adult females. A. womersleyi adult females treated with five acaricides produced $52{\sim}93%$ as many eggs as untreated adult females. And A. eharai adult females treated with five acaricides laid $54{\sim}73%$ as many eggs as untreated adult females. The remaining acaricides showed high toxicity to adult females of A. womersleyi and A. eharai. All the insecticides tested were less toxic to T. urticae adult females than to adult females of A. womersleyi and A. eharai. However, tebufenozide and diflubenzuron did not significantly affect the survival and reproduction of adult females of A. womersleyi and A. eharai. All the fungicides tested showed low mortality (${\leq}24%$) to adult females of predatory mites. However, benomyl had significant effect on the reproduction of adult females of A. womersleyi and A. eharai. Four acaricides (bifenazate, acequinocyl, flufelloxuron and chlorfenapyr) were much less toxic to eggs of A. womersleyi and A. eharai than to T. urticae eggs. However, etoxazole caused relatively low hatchability ($58{\sim}62%$) of eggs of A. womersleyi and A. eharai. All the insecticides and fungicides tested did not significantly affect the hatch of eggs of predatory mites. It may be suggested from these results that four acaricides, two insecticides and four fungicides described could be Incorporated into the integrated mite management system with A. womersleyi and A. eharai in pear orchard.

• The Korean Journal of Pesticide Science
• /
• v.4 no.4
• /
• pp.81-86
• /
• 2000

The objective was to develop herbicides for liquorice (Glycyrrhiza uralensis), one of most important ingredients of herbal medicine in Korea. Soil-applied herbicides, pendimethalin at 1,585 g a.i. $ha^{-1}$, simazine at 1,000 g a.i. $ha^{-1}$, alachlor at 5 g a.i. $ha^{-1}$, metolachlor at 1,600 g a.i. $ha^{-1}$, and ethalfluralin at 1,050 g a.i. $ha^{-1}$ provided greater control of hairy crabgrass and barnyardgrass (> 60%) but less control of Abutilon avicennae and Fagopyrum esculentum under growth chamber conditions. Of tested soil-applied herbicides, pendimethalin and simazine showed slight injury to liquorice (<17%). In the field experiment conducted in Chunchon, pendimethalin and simazine provided greater control of weeds: total fresh weight of weeds in control plots was 187 g $m^{-2}$, while those in both herbicides-treated plots were nil. Fresh weights of liquorice seedlings in pendimethalin- and simazine-applied plots, however, were not different from those in control plots. Foliar-applied herbicides, such as dicamba at 964 g a.i. $ha^{-1}$, 2,4-D at 280 g a.i. $ha^{-1}$, mecoprop at 2,500 g a.i. $ha^{-1}$, flazasulfuron at 75 g a.i. $ha^{-1}$, imazaquin at 800 g a.i. $ha^{-1}$, bentazon at 1,600 g a.i. $ha^{-1}$, and pyribenzoxim at 30 g a.i. $ha^{-1}$ reduced the growth of liquorice seedlings and provided moderate to total damage. Overall results show that pendimethalin and simazine appears to be effective herbicide candidates for liquorice.

• The Korean Journal of Pesticide Science
• /
• v.4 no.4
• /
• pp.19-25
• /
• 2000

The leaching behaviour of quinclorac was elucidated using soil columns. On top of each glass column packed with a rice paddy soil up to the 30 cm height were applied three different treatments of [$^{14}C$]quinclorac: quincloiac only (T-1), quinclorac adsorbed onto active carbon (T-2), and quinclorac adsorbed onto a mixture of active carbon and $Ca(OH)_{2}$ (T-3). Half of the columns were planted with rice plants for 17 weeks and half of them unplanted for comparison. Average amounts of $^{14}C$-activity percolated from tile soil columns without rice plants in T-1, T-2, and T-3 were 81.1%, 27.8% and 48.0%, respectively, of tile originally applied $^{14}C$, whereas those with rice plants grown were 36.8%, 9.6% and 11.0%, respectively, indicating that the leaching of [$^{14}C$]quinclorac was significantly affected by vegetation and by treatment with the adsorbents. The bioavailability of the herbicide to rice plants in T-1, T-2, and T-3 were 13.6%, 11.0% and 13.9%, respectively. The residue levels of quinclorac in the edible part of rice grains would be far less than the maximum residue limit (MRL, 0.5 ppm). After the leaching, the amounts of $^{14}C$ remaining in soil in with rice planting T-1, T-2, and T-3 were 36.3%, 73.7%, and 61.8%, whereas those without rice planting were 19.7%, 71.1%, and 52.3%, respectively. The balance sheets indicate that [$^{14}C$]quinclorac translocated to rice shoots would be lost by volatilization and/or in other ways in T-1 and T-3. The $^{14}C$-activity partitioned into the aqueous phase of the leachates collected from all treatments was less than 7% of the total, but it increased gradually with time in the case of rice growing, suggesting tile formation of some polar degradation products.

• The Korean Journal of Pesticide Science
• /
• v.20 no.1
• /
• pp.14-22
• /
• 2016

A trial of combining and quantifying the effects of food processing on various pesticides was carried out using a meta-analysis. In this study, weighted mean response ratios and confidence intervals about the reduction of pesticide residue levels in fruits and vegetables treated with various food processing techniques were calculated using a statistical tool of meta-analysis. The weighted mean response ratios for tap water washing, peeling, blanching (boiling) and oven drying were 0.52, 0.14, 0.34 and 0.46, respectively. Among the food processing methods, peeling showed the greatest effect on the reduction of pesticide residues. Pearsons's correlation coefficient (r=0.624) between weighted mean response ratios and octanolwater partition coefficients ($logP_{ow}$) for twelve pesticides processed with tap water washing was confirmed as having a positive correlation in the range of significance level of 0.05 (p=0.03). This means that a pesticide having the higher value of $logP_{ow}$ was observed as showing a higher weighted mean response ratio. These results could be used effectively as a reference data for processing factor in risk assessment and as an information for consumers on how to reduce pesticide residues in agricultural products.

• The Korean Journal of Pesticide Science
• /
• v.13 no.1
• /
• pp.39-44
• /
• 2009

This study was conducted to evaluate the actual risk of fipronil on worker honey bees (Apis mellifera L.) through acute contact toxicity test, acute oral toxicity test, toxicity of residues on foliage test, and small scale field test. The $48h-LD_{50s}$ of fipronil SC on honeybee were $0.005{\mu}g$ a.i./bee in acute contact toxicity test and $0.004{\mu}g$ a.i./bee in acute oral toxicity test, respectively. In toxicity of residues on foliage test, fipronil showed over 90% of mortality during 28days after treatment at recommended application rate. The $DT_{50}$ of dislodgeable foliar residue was 9 days. Finally, In small scale field test, fipronil showed similar toxicity in the residues on foliage test. It was concluded that fipronil has very high acute toxicity and long residual toxicity to honeybee. Therefore, fipronil is highly toxic to bees exposed to direct treatment or residues on blooming crops or weeds. Do not apply this product or allow it to drift to blooming crops or weeds if bees are visiting the treatment area. To protect honeybee and wild pollinators from outdoor use of fipronil, ultimately it should need to limit for only indoor use to prevent pollinators from unintentionally exposure of fipronil.

• The Korean Journal of Pesticide Science
• /
• v.18 no.2
• /
• pp.115-121
• /
• 2014

This study was performed to investigate the effect of conidial density, wetness period and temperature on conidial germination, appressoria formation and disease incidence. While there was not significantly correlated between conidial density and temperature, and conidial germination and appressoria formation, there was a significant correlation between those factors and disease incidence. The longer wetness period was, the higher the ratio of conidial germination, appressoria formation and the disease incidence was. The optimum conidial density, temperature and wetness period was $1{\times}10^6$ conidia $mL^{-1}$, $30^{\circ}C$ and 5 days, respectively. In case the wetness period was more than 5 days, the typical symptom was not found on pepper fruits because of the overgrowth of mycelia. Using this fruit assay method, which the pepper anthracnose pathogens were inoculated by spraying spore suspension on non-wounded or wounded pepper fruits, control effect of three fungicides were evaluated against pepper anthracnose by the protective and/or the curative application. Propineb showed high protective control activity, while it showed curative control activity on unwounded fruits, but did not showed curative control activity on wounded fruits. Tebuconazole, one of curative fungicide, showed higher control activity in non-wound inoculation than wound inoculation. Trifloxystrobin, one of strobilurin group, showed high both protective and control activity against anthracnose. In conclusion, we supposed that the newly developed in vitro pepper fruit assay can be used to evaluate antifungal activity of control agents against pepper anthracnose.

• Korean Journal of Cognitive Science
• /
• v.23 no.1
• /
• pp.109-132
• /
• 2012

According to recent embodied cognition approach, understanding of actions is not based on abstract symbolic process but based on mental simulation of sensory-motor information related to those actions. As supporting evidence, motor resonance effect is a facilitation/interference effect of motor response in terms of similarity between observed action and concurrent own action. In the current research, we investigated this effect in the situation to perceive a complex social action perception and how it would be modulated by perspectives of construals of the social action scene. For this purpose, we created three kinds of fighting action scenes of two people in terms of body actions of the subject(ie., hitting, stepping, biting), and described them in two perspectives; active and passive. During the experiment, subjects had to verify the congruency of the picture and the description first, and if they are congruent, they had to do two different actions in terms of color of following cues. In the first experiment, subjects' response time for stepping on a pedal and pressing a button were analyzed for measuring motor resonance effect for the foot movement. In the second experiment, voice response time with a microphone and button pressing time were analyzed for the mouth movement motor resonance effect. Results showed the facilitation of the foot movement(in Exp1), and the mouth movement(in Exp2) only when the action scene was described in active perspective. Our results indicate that the motor resonance effect can be occurred during perception of social actions in the real life situation, but it can be also modulated by the perspective of the mental construal of the action event.

• Journal of KIISE:Information Networking
• /
• v.35 no.2
• /
• pp.99-111
• /
• 2008

In recent years, the needs for WLANs(Wireless Local Area Networks) technology which can access to Internet anywhere have been dramatically increased particularly in SOHO(Small Office Home Office) and Hot Spot. However, unlike wired networks, there are some unique characteristics of wireless networks. These characteristics include the burst packet losses due to unreliable wireless channel. Note that burst packet losses, which occur when the distance between the wireless station and the AP(Access Point) increase or when obstacles move temporarily between the station and AP, are very frequent in 802.11 networks. Conversely, due to burst packet losses, the performance of 802.11 networks are not always as sufficient as the current application require, particularly when they use TCP at the transport layer. The high packet loss rate over wireless links can trigger unnecessary execution of TCP congestion control algorithm, resulting in performance degradation. In order to overcome the limitations of WLANs environment, MAC-layer LDA(Loss Differentiation Algorithm)has been proposed. MAC-layer LDA prevents TCP's timeout by increasing CRD(Consecutive Retry Duration) higher than burst packet loss duration. However, in the wireless channel with high packet loss rate, MAC-layer LDA does not work well because of two reason: (a) If the CRD is lower than burst packet loss duration due to the limited increase of retry limit, end-to-end performance is degraded. (b) energy of mobile device and bandwidth utilization in the wireless link are wasted unnecessarily by Reducing the drainage speed of the network buffer due to the increase of CRD. In this paper, we propose a new retransmission module based on Cross-layer approach, called BLD(Burst Loss Detection) module, to solve the limitation of previous link layer retransmission schemes. BLD module's algorithm is retransmission mechanism at IEEE 802.11 networks and performs retransmission based on the interaction between retransmission mechanisms of the MAC layer and TCP. From the simulation by using ns-2(Network Simulator), we could see more improved TCP throughput and energy efficiency with the proposed scheme than previous mechanisms.

• Cartoon and Animation Studies
• /
• s.34
• /
• pp.317-344
• /
• 2014

Perspectives on the basis of arts and cultural management, this study intends to suggest improvements in core curriculums that are required in order for South Korea, a country that has initiated into the animation industry through outsourcing from big-budget animation production countries such as America and Japan, to develop its own strong base in creative animation industry. The perspectives of arts management in this context means an integration nexus between human studies, social science and management, and suggestions are as follow: First, it is crucial to understand the current trend of animation industry structure across the globe, as well as to develop the ability of co-production. Animation industry often requires technical skills, capital strength and human resources, each having equal importance. Therefore, thorough analysis of the three components in worldwide animation industry must be preceded for animation production services. To do so, collaboration with major animation creation countries is the best option and is highly encouraged, so that the national animation curriculum shall be enhanced to meet such demands and hence develop various abilities. The second is a good understanding of new-media and new-platforms. Not only the traditional distributor of animation such as television and theater, the distribution system expands its scope to a variety of online sources including pod-casts and the Internet. Under these circumstances, a deep understanding towards animation distribution system and an analysis of the new consumer channel are also of paramount importance for animation production. Third, a possibility of animation supply chain through diversified routes and media have paved the way for a possible animation production services and distribution without a mega-budget. Thus, new curriculum shall need to reinforce marketing and management aspects that will in turn help individuals to establish a self-employed creative business. Last but not least, this study further includes illustration of current curriculum of animation studies in national universities, followed by detailed suggestions for the curriculum improvements based on the above mentioned three factors. It was observed that the current curriculums have been solely focused on practical works and technical skills of animation and art studies; a four-year-course colleges that provide animation courses usually lack components of human studies, social science and management. Thus, this study proposes essential contexts of management studies that are needed for individual business and also curriculum improvements that are derived from the analysis of the current industry and the new media.

• Clinical and Experimental Pediatrics
• /
• v.52 no.10
• /
• pp.1109-1118
• /
• 2009

Purpose : Metabolic syndrome (MS), characterized by obesity and insulin resistance, elicits risk factors such as hyperlipidemia, hypertension, and glucose intolerance with additive effects on atherosclerosis, leading to cardiovascular diseases. The purposes of this study were to evaluate the prevalence of MS among overweight and obese adolescents and to investigate the impact of obesity on the cardiovascular system. Methods : In all, 684 adolescents were included in the study. Blood pressure, body mass index (BMI), fasting blood glucose, total cholesterol, triglyceride, low-density-lipoprotein (LDL)-cholesterol, high-density-lipoprotein (HDL)-cholesterol, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and high-sensitive C-reactive protein (hs-CRP) were measured in the patients with a BMI of >85 percentile. Brachial-ankle pulse wave velocity (BaPWV) and ankle brachial index were measured using Vascular Profiler (VP)-1000. Results : MS was confirmed in 19.5% of the overweight and obese adolescents and 50.8% of the obese adolescents. The systolic and diastolic blood pressure, height, weight, fat mass, %fat, BMI, obesity index, and waist circumference were higher in the overweight and obese adolescents with MS. Moreover, the triglyceride, AST, ALT, and hs-CRP levels were higher, whereas HDL-cholesterol level was significantly lower in this group. The overweight and obese adolescents with MS showed shorter diastolic and systolic times, higher heart rate and BaPWV, and longer E-wave deceleration time by echocardiography. Conclusion : Overweight and obese adolescents showed characteristic MS features such as hypertension and hyperlipidemia. Thus, obese adolescents predisposed to MS should be provided early treatment for obesity.