• Korean journal of applied entomology
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• v.48 no.4
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• pp.493-501
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• 2009

To investigate resistance of Myzus persicae, which is resistant to etofenprox belonging to pyrethriods, to other insecticides, fenpropathrin and thiamethoxam, mortality and $LC_{50}$ values for these two insecticides against the etofenprox-resistant and -susceptible populations were obtained and EPG analysis for feeding behaviors of thiamethoxam or fenpropathrin treated and non-treated M. persicae was conducted. For fenpropathrin, mortality after 48 h treatment was 28 and 29%, respectively for the resistant and susceptible population. The $LC_{50}$ value was 193.15 and 93.46 ppm, respectively. For thiamethoxam, mortality after 48 h treatment was 87 and 57%, respectively for the resistant and susceptible population. The $LC_{50}$ value was 3.17 and 30.34 ppm, respectively. There was no significant difference in feeding behavior between fenprorpathrin treated and non-treated M. persicae. They showed a continuous feeding pattern. However, contact signal frequency increased in the thiamethoxam treated M. persicae 1 hour after treatment and significant difference was shown.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.519-526
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• 2009

Bacillus thuringiensis subsp. kurstaki KB100 isolated from the domestic soil have the most effective activity against the beet armyworm, Spodoptera exigua larva. The tannic acid as protease inhibitor might be increased the efficacy of sublethal concentrations of B. thuringiensis. The tannic acid was identified as a protease inhibitor that could increased the efficacy of sublethal concentrations of B. thuringiensis. Mixture of B. thuringiensis and tannic acid was investigated the mortality of S. exigua larva in the laboratory and field. When B. thuringiensis treated to 2nd larva of S. exigua, mortality was shown 54.4%. However, mixtures of B. thuringiensis with 4 and 40 mM tannic acid were increased mortalities to 2nd larva of S. exigua as 64.0 and 95.5%, respectively. Also, synergy effect of mixture of B. thuringiensis and 40 mM tannic acid was increased the mortality of S. exigua 3rd larva to 93.3%, even though 60.0% mortality with only B. thuringiensis treatment. On the other hand, the mortality of mixture with B. thuringiensis and 80 mM tannic acid was 53.3% lower than B. thuringiensis single treatment. In the welsh onion field, the accumulated mortalities of 3 times replicated with mixture of B. thuringiensis and 40 mM tannic acid were 83.9, 89.4 and 66.8% compare with 61.8, 80.4 and 47.3% as only B. thuringiensis treatment, respectively.

• Journal of the Ergonomics Society of Korea
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• v.36 no.3
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• pp.183-196
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• 2017

Objective: The purpose of this research was to assess the agreement between job physical risk factor analysis by ergonomists using ergonomic methods and physical examinations made by occupational physicians on the presence of musculoskeletal disorders of the upper extremities. Background: Ergonomics is the systematic application of principles concerned with the design of devices and working conditions for enhancing human capabilities and optimizing working and living conditions. Proper ergonomic design is necessary to prevent injuries and physical and emotional stress. The major types of ergonomic injuries and incidents are cumulative trauma disorders (CTDs), acute strains, sprains, and system failures. Minimization of use of excessive force and awkward postures can help to prevent such injuries Method: Initial data were collected as part of a larger study by the University of Utah Ergonomics and Safety program field data collection teams and medical data collection teams from the Rocky Mountain Center for Occupational and Environmental Health (RMCOEH). Subjects included 173 male and female workers, 83 at Beehive Clothing (a clothing plant), 74 at Autoliv (a plant making air bags for vehicles), and 16 at Deseret Meat (a meat-processing plant). Posture and effort levels were analyzed using a software program developed at the University of Utah (Utah Ergonomic Analysis Tool). The Ergonomic Epicondylitis Model (EEM) was developed to assess the risk of epicondylitis from observable job physical factors. The model considers five job risk factors: (1) intensity of exertion, (2) forearm rotation, (3) wrist posture, (4) elbow compression, and (5) speed of work. Qualitative ratings of these physical factors were determined during video analysis. Personal variables were also investigated to study their relationship with epicondylitis. Logistic regression models were used to determine the association between risk factors and symptoms of epicondyle pain. Results: Results of this study indicate that gender, smoking status, and BMI do have an effect on the risk of epicondylitis but there is not a statistically significant relationship between EEM and epicondylitis. Conclusion: This research studied the relationship between an Ergonomic Epicondylitis Model (EEM) and the occurrence of epicondylitis. The model was not predictive for epicondylitis. However, it is clear that epicondylitis was associated with some individual risk factors such as smoking status, gender, and BMI. Based on the results, future research may discover risk factors that seem to increase the risk of epicondylitis. Application: Although this research used a combination of questionnaire, ergonomic job analysis, and medical job analysis to specifically verify risk factors related to epicondylitis, there are limitations. This research did not have a very large sample size because only 173 subjects were available for this study. Also, it was conducted in only 3 facilities, a plant making air bags for vehicles, a meat-processing plant, and a clothing plant in Utah. If working conditions in other kinds of facilities are considered, results may improve. Therefore, future research should perform analysis with additional subjects in different kinds of facilities. Repetition and duration of a task were not considered as risk factors in this research. These two factors could be associated with epicondylitis so it could be important to include these factors in future research. Psychosocial data and workplace conditions (e.g., low temperature) were also noted during data collection, and could be used to further study the prevalence of epicondylitis. Univariate analysis methods could be used for each variable of EEM. This research was performed using multivariate analysis. Therefore, it was difficult to recognize the different effect of each variable. Basically, the difference between univariate and multivariate analysis is that univariate analysis deals with one predictor variable at a time, whereas multivariate analysis deals with multiple predictor variables combined in a predetermined manner. The univariate analysis could show how each variable is associated with epicondyle pain. This may allow more appropriate weighting factors to be determined and therefore improve the performance of the EEM.

• Korean Journal of Plant Resources
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• v.33 no.4
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• pp.279-286
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• 2020

Purple loosestrife-Lythrum anceps (Koehne) Makino is a herbaceous perennial plant belonging to the Lythraceae family. It has been used for centuries in Korea and other Asian traditional medicine. It has been showed pharmacological effects, including anti-oxidant and anti-microbial effects. However, the mechanisms underlying its anti-cancer effect are not yet understood. In this study, we investigated the mechanism of apoptosis signaling pathways by ethanol extract of Lythrum anceps (Koehne) Makino (ELM) in human leukemia U937 cells. Treatment with ELM significantly inhibited cell growth in a dose-dependent manner by inducing apoptosis, as evidenced by the formation of apoptotic bodies (ApoBDs), DNA fragmentation and increased populations of sub-G1 ratio. Induction of apoptosis by ELM was connected with up-regulation of death receptor (DR) 4 and DR5, pro-apoptotic Bax protein expression and down-regulation of anti-apoptotic Bcl-2 protein, and inhibitor of apoptosis protein (IAP) family proteins, depending on dosage. This induction was associated with Bid truncation, mitochondrial dysfunction, proteolytic activation of caspases (-3, -8 and -9) and cleavage of poly(ADP-ribose) polymerase protein. Therefore, our data indicate that ELM suppresses U937 cell growth by activating the intrinsic and extrinsic apoptosis pathways, and thus may have applications as a potential source for an anti-leukemic chemotherapeutic agent.

• Korean Journal of Plant Taxonomy
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• v.39 no.1
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• pp.42-47
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• 2009

In this study, the somatic chromosome of 14 taxa of Korean Galium L. were investigated. Among them were a few taxa for which the somatic chromosome number was determined for the first time. The somatic chromosome numbers of Korean Galium L. were 2n = 22, 24, 44, 48, 66, 72, 77, 88 and so basic chromosome numbers were x = 11 or 12. Those taxa having the basic chromosome number x = 11 showed polyploidy, including diploid, tetraploid, heptaploid, and octoploid. Tetraploid and hexaploid can be observed in those taxa with the basic number x = 12. The eleven taxa reported 11 for the first time are G. spurium var. echinospermon (Wallr.) Hayek (2n = 44), G. gracilens (A. Gray) Makino (2n = 22), G. pogonanthum Franch. & Sav. (2n = 22, 44), G. trachyspermum A. Gray (2n = 22, 44), G. japonicum (Maxim.) Makino & Nakai (2n = 77), G. trifloriforme Kom. (2n = 44), G. dahuricum Turcz. var. dahuricum (2n = 48, 72), G. dahuricum var. tokyoense (Makino) Cufod. (2n = 22), G. kinuta Nakai & Hara (2n=66), G. verum var. trachycarpum for. nikkoense (Nakai) Ohwi (2n = 44), G. verum var. asiaticum for. pusillum (Nakai) M. Park (2n = 44). The taxa with the same chromosome numbers as previously reported ones were G. boreale L. (2n=22) and G. verum var. asiaticum Nakai for. asiaticum (2n = 44). The chromosome number of G. trifidum L. (2n = 22) was different from the previous report. Two infraspecific taxa of G. dahuricum showed differences in their basic chromosome numbers (x = 11 for G. dahuricum Turcz. var. dahuricum and x = 12 for var. tokyoense (Makino) Cufod. The somatic chromosome number for G. dahuricum Turcz. var. dahuricum was found to be 2n = 48 (tetraploid) or 72 (hexaploid), while that of G. dahuricum var. tokyoense (Makino) Cufod. was found to be 2n = 22 (diploid). Therefore, basic chromosome numbers for members of the genus Galium can be used as valuable characters in delimiting infrageneric sections and investigating interspecific relationships.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.517-528
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• 2007

Domestic or international existing researches regarding rail damage factors are focused on laying, vehicle conditions, driving speed and driving habits and overlook characteristics of track structure (elasticity, maintenance etc). Also in ballast track, as there is no special lateral spring stiffness of track also called as ballast lateral resistance in concrete track, generally, existing study shows concrete track has 2 time shorter life cycle for rail replacement than ballast track due to abrasion. As a result of domestic concrete track design and operation performance review, concrete track elasticity is lower than track elasticity of ballast track resulting higher damage on rail and tracks. Generally, concrete track has advantage in track elasticity adjustment than ballast track and in case of Europe, in concrete track design, it is recommended to have same or higher performance range of vertical elastic stiffness of ballast track but domestically or internationally review on lateral spring stiffness of track is very minimal. Therefore, through analysis of service line track on site measurement and analysis on performance of maintenance, in this research, dynamic characteristic behaviors of commonly used ballast and concrete track are studied to infer elasticity of service line track and experimentally prove effects of track lateral spring stiffness that influence curved rail damage as well as correlation between track elasticity by track system and rail damage to propose importance of appropriate elastic stiffness level for concrete and ballast track.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.480-493
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• 2007

Many railway-advanced countries are using the various types of track to reduce the track maintenance and repair cost according to the improvement of velocity. It spends on much maintenance and repair cost for ballast track due to abrasion of ballast, track irregularity and unisotropical ballast-support stiffness. The ballast track on railway bridge is accelerating the deterioration of ballast according to interaction of railway bridge and track. As continuing the deterioration, it is caused dynamic loads. Due to these effects, it increases negative loads of track and bridge. However, when designing the railway bridge, the effect of ballast track was applicate only dead load, so elastic behavior effect of ballast track is not influenced. Therefore, this paper presumes the stiffness of ballast track on railway bridge considering dynamic behavior of railway bridge, it was evaluated that effect on dynamic behaviors of railway bridge according to ballast track stiffness.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.32 no.1 s.55
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• pp.45-51
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• 2006

In the field of makeup cosmetics, especially, powder-based foundations such as two-way cake, pact and face powder, the quality of which is known to be strongly influenced by the properties of powder, surface treatment technology is widely used as a method to improve the various characteristics of powder texture, wear properties, dispersion ability and so on. The two-way cake or pressed-powder foundation is one of the familiar makeup products in Asian market for deep covering and finishing purpose. In spite of the relent progress in surface modification method such as composition of powders with different characteristics and application of a diversity of coating ingredient (metal soap, amino acid, silicone and fluorine), this product possess a technical difficulty to enhance both of the adhesion power and spreadability on the skin in addition to potential claim of consumer about heavy or thick feeling. This article is covering the preparation and coating method of nano-vesicle that mimic the double-layered lipid lamellar structure existing between the corneocytes of the stratum corneum in the skin for the purpose of improving both of two important physical characteristic of two-way cake, spreadability and adhering force to skin, and obtining better affinity to skin. Nano-vesicle was prepared using the high-pressure emulsifying process of lecithin, pseudo ceramide, butylene glycol and tocopheryl acetate. This nano-sized emulsion was added to powder-dispersed aqueous phase together with bivalent metal salt solution and then the filtering and drying procedure was followed to yield the nano-vesicle coated powder. The amount of nano-vesicle coated on the powder was able to regulated by the concentration of metal salt and this novel powder showed the lower friction coefficient, more uniform condition of application and higher adhesive powder comparing with the alkyl silane treated powder from the test result of spreadability and wear properties using friction meter and air jet method. Two-wav cake containing newly developed coated powder with nano-vesicle showed the similar advantages in the frictional and adhesive characteristics.

• Journal of the Korean Geophysical Society
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• v.3 no.1
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• pp.57-66
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• 2000

The location and geometry of the Ulsan Fault play important roles in interpreting tectonic evolution of the southeastern part of the Korean Peninsula. Dipole-dipole electrical resistivity surveys and seismic refraction surveys were carried out in the Yaksoo area, Ulsan in order to measure the thickness of the alluvium covering the Ulsan Fault and to find associated fracture zones and possibly the location of its major fault plane. The collected data were analyzed and interpreted. Some results reported previously by others were also used in this interpretation. No low resistivity anomalies were found in the cross-sectional resistivity image of the survey line located in the east of the Dong River. In contrast, well-developed continuous low resistivity anomalies were detected in the west of the Dong River. This strongly suggests that the major fault plane of the Ulsan Fault is located under or in the west part of the Dong River. Two refraction boundaries corresponding to the underground water level and the bottom of the alluvium were found by refraction surveys carried out on the limited part of the east survey line. The thickness of the alluvium was found to be about 30 m. Small faults in the basement rock identified by reflection surveys were not detected by both resistivity and refraction seismic surveys. This might be explained by assuming that low resistivity anomaly is more closely related to the clay contents than the water contents. On the other hand, it may be resulted by the limited resolution of the resistivity and refraction surveys. Detailed study is required to clarify the reason. Resistivity survey is frequently considered to be a good exploration method to detect subsurface faults. However, it appears to be less useful than reflection seismic survey in this work. In dipole-dipole resistivity survey, the number of separation should be increased to survey deeper subsurface with the same resolution. However, signal to noise ratio decreases as the number of separation increases. In this survey area, the signal to noise ratio of up to sixteen separations was good enough based on the statistical properties of measurements.

• 한국지구물리탐사학회:학술대회논문집
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• 2004.08a
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• pp.49-69
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• 2004

One of the important roles of geophysical exploration in archeological survey may be to provide the subsurface information for effective and systematic excavations of historical remains. Ground Penetrating Radar (GPA) can give us images of shallow subsurface structure with high resolution and is regarded as a useful and important technology in archeological exploration. Since the buried cultural relics are the three-dimensional (3-D) objects in nature, the 3-D or areal survey is more desirable in archeological exploration. 3-D GPR survey based on the very dense data in principle, however, might need much higher cost and longer time of exploration than the other geophysical methods, thus it could have not been applied to the wide area exploration as one of routine procedures. Therefore, it is important to develop an effective way of 3-D GPR survey. In this study, we applied 3-D GPR method to investigate the possible historical remains of Baekje Kingdom at Gatap-Ri, Buyeo city, prior to the excavation. The principal purpose of the investigation was to provide the subsurface images of high resolution for the excavation of the surveyed area. Besides this, another purpose was to investigate the applicability and effectiveness of the continuous data acquisition system which was newly devised for the archeological investigation. The system consists of two sets of GPR antennas and the precise measurement device tracking the path of GPR antenna movement automatically and continuously Besides this hardware system, we adopted a concept of data acquisition that the data were acquired arbitrary not along the pre-established profile lines, because establishing the many profile lines itself would make the field work much longer, which results in the higher cost of field work. Owing to the newly devised system, we could acquire 3-D GPR data of an wide area over about $17,000 m^2$ as a result of the just two-days field work. Although the 3-D GPR data were gathered randomly not along the pre-established profile lines, we could have the 3-D images with high resolution showing many distinctive anomalies which could be interpreted as old agricultural lands, waterways, and artificial structures or remains. This case history led us to the conclusion that 3-D GPR method can be used easily not only to examine a small anomalous area but also to investigate the wider region of archeological interests. We expect that the 3-D GPR method will be applied as a one of standard exploration procedures to the exploration of historical remains in Korea in the near future.