• Research in Plant Disease
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• v.16 no.3
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• pp.274-278
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• 2010

Potato late blight caused by Phytophthora infestans was the most constrain disease at potato cultivation areas. The mating type distribution and fungicides response of P. infestans were investigated to elucidate the changes of pathogen from Gangwon province. On the fungal isolates in 2006, 58.7% were A1 mating type and 41.3% were A2 mating type. In 2007, A1 mating type isolates increased to 93.3% and A2 mating type isolates were collected from Jinbu areas as much as 6.7%. About 234 isolates analysed for metalaxyl response, the results was resistance 73.7%, intermediate 18.8% and sensitive 7.5% in 2006. And it was resistance 59.4%, intermediate 4.0% and sensitive 36.6% in 2007. It meant that mating type distribution and fungicide response were very different over the collection sites. Minimal inhibition concentration (MIC) of dimethomorph examined with 126 isolates in 2006 and 106 isolates in 2007. MIC over $1.0\;{\mu}g/ml$ was 56.3% in 2006 and it was 3.8% in 2007. The average $EC_{50}$ value of P. infestans was $0.37\;{\mu}g/ml$ in 2006, but it decreased to $0.12\;{\mu}g/ml$ in 2007. Fungicides response and pathogenesis of P. infestans should be monitored continuously to enhance the chemical efficacy at potato fields.

• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.24-32
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• 1985

The worm development and egg laying pattern of Echinostoma hortense (Trematoda; Echinosto-matidae) were studied in albino rats and the brief clinical course was observed in human volunteers. A total of 21 rats were infected with 20~69 metacercariae each and two humans were with 7 and 27 metacercariae, which were collected from the loaches. For recovery of worms, the rats were sacrificed at irregular intervals from the 6th to 150th day after infection and the human volunteers were treated with praziquantel and purged with magnesium salt on the 26~27th day. The stools of the rats and humans were examined for the eggs. The results were as follows: 1. The worm recovery rate from the rats was not affected by the increase of infection time but varied individually; 9.1~50.0% (31.1 % in average). From humans, 14.3% and 37.0% (32.4% in average) of challenged were recovered. 2. In the rats, it was revealed that the worms rapidly grew for the first 14 days to become 7.59mm in average length and 1.17mm in average width but the growth became much slower thereafter until the 150th day; 7.95mm in length on the 21 th day, 9.04mm on the 28th day, 10.21mm on the 49th day and 12. 62mm on the 150th day. During the early stage of infection, the growth of genital organs (male or female) was expressed as sigmoid curves whereas non-genital organs (such as suckers) was simply as straight lines. 3. The prepatent period of this fluke was 10~12 days in the rats and 16~17 days in men. After the start of oviposition, the egg production by the worms remarkably increased, reached maximum on the 32~33th day, followed by decrease thereafter. The maximum value of E.P.G./worm was 390. 4. The major subjective symptoms in human volunteers were abdominal pain and diarrhea during the early stage of infection. The results show that human is as susceptible as the rats to E. hortense infection and the amount of egg production in the rats is greatly affected by the age of worms.

• Applied Biological Chemistry
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• v.51 no.3
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• pp.194-199
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• 2008

The biological activities of water and ethanol extracts from different fruit parts, such as peel, flesh, and placenta of oriental melon were investigated. The total phenolic concentration of water extract was the highest such as 151.64 ${\mu}g/g$ in the peel, also that of ethanol extract was 224.77 ${\mu}g/g$ in the peel, respectively. The total flavonoid content in the water and ethanol extracts were high such as 45.53 ${\mu}g/g$ and 67.16 ${\mu}g/g$ of peel, respectively. In the physiological activities, DPPH in the water and ethanol extracts were high such as 25.0% and 83.3% of peel in 1% concentration. Extract of peel was higher than those of flesh and placenta. ABTS in the water extracts was 79.2% of peel, 57.6% of flesh and 74.0% of placenta in 1% concentration. Ethanol extracts was 99.9% of peel, 52.1% of flesh and 41.2% of placenta in 1% concentration. In addition, xanthine oxidase inhibitory activity and ${\alpha}$-Glucosidase inhibition activity of the peel of water and ethanol extracts appeared to be higher than those of placenta and flesh. This study showed that the antioxidant and ${\alpha}$-Glucosidase inhibition activity of peel extracts were higher than those of placenta and flesh. Also, the antimicrobial effect of ethanol extract from different fruit parts was shown only on Streptococcus agalactiae.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.269-277
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• 2014

The multiclass pesticide multiresidue method for the simultaneous determination of diflubenzuron in agricultural products was conducted by using HPLC-UVD. The method was validated through the guidelines of linearity, specificity, limit of detection (LOD), limit of quantification (LOQ), accuracy and precision with pesticide-free spinach, Korean cabbage, eggplant, squash, sweet pepper, cucumber, Korean melon. The calibration curve of diflubenzuron was linear over the concentration range of 0.05-5 mg/kg with correlation coefficient of above 0.99999. The limit of detection and quantification was 0.008 and 0.02 mg/kg. Mean recoveries of diflubenzuron for each sample were 77.5-105.6%. Relative standard deviation (RSD) in recoveries were all less than 20%. The intra-day and inter-day precision (RSD) were 0.4-1.9% and 0.7-1.9%, respectively. The result of validation indicated that this method was accurate and rapid assay.

• The Korean Journal of Pesticide Science
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• v.3 no.3
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• pp.60-67
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• 1999

Insecticidal activities of imidacloprid to sucking type insect pests, brown planthopper (BPH, Nilaparvata lugens) and peen peach aphid (GPA Myzus persicae), to chewing type insect pests, tobacco cut worm (TCW; Spodoptera litura) and beet armyworm (BAW, Spodoptera exigua) and to spiders, Pirata subpiraticus, Pachygnata clercki and Ummeliata insecticeps, as natural enemies were investigated by several bioassay methods. $LD_{50}$ of the chemical by topical treatment to BPH was 0.015 ${\mu}g/g$(48 hrs), while $LC_{50}s$ by leaf dipping and root zone treatment were 18.1 and 21.5 ppm, respectively. There was no difference in insecticidal activities between leaf dipping and root zone treatment. Imidacloprid also showed ovicidal effect of root zone treatment and its $LC_{50}$ was 6.8ppm $LD_{50}$ (48 hrs after treatment) of imidacloprid to GPA was $0.4{\mu}g/g$ in case of topical application and $LC_{50}s$ by leaf dipping and root zone treatment were 1.9 ppm and 13.7 ppm respectively. Leaf dipping was more effective than root zone treatment in GPA At topical application $LD_{50}$ (48 hrs after treatment) of imidacloprid to chewing type insect pests, TCW and BAW, were greater than 1,492 and $312{\mu}g/g$ and $LC_{50}s$ by leaf dipping method were 4,803 and Heater than 5,000ppm respectively. This means that imidacloprid has much less effect on chewing type insect pests, TCW and BAW. $LD_{50}$(48 hrs after treatment) of imidacloprid to wandering spiders, Pirata subpiraticus, Pachygnata clercki at topical application were greater dan $2941{\mu}g/g$ and greater than $2,976{\mu}g/g$ respectively and that to webbing spider, Ummeliata insecticeps, was 357 ${\mu}g/g$. Imidacloprid showed very low toxicity to the spiders and its selective toxicity ratios between spiders and BPH were greater than 19,600, greater than 19,800 and 23,800, respectively.

• Journal of Distribution Science
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• v.9 no.2
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• pp.73-81
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• 2011

This study is designed to examine the effects of information source effects of the word mouth have on the formed expectations for the private institution and to explore the formed expectations' effects on the actual sales of the educational service. Moreover, its purpose is in analyzing what medication effects the pre-conceived expectation has on selecting the educational service. After testing hypothesis, the results showed that the source effects of the information from word of mouth had a significant effect on the expectation factors, in terms of expertise, similarity, likability and familiarity expectation factors. However, it was found that effect was not significant for the truthfulness. The significant result was found on the expectation factors before visiting the private institution on selecting educational service, indicating a positive effect. As for the influence of source of the word of mouth information on selecting educational service, the results from the mediation effects of the expectation factors on selecting the educational service showed that for expectation factors, expertise had the partial mediation effect, truthfulness, perfect mediating effect, similarity, partial mediation effect, likability, perfect mediating effect, and familiarity, perfect mediating effect. A test of the mediating role of attribute expectations in the influence of WOM message source attributes on educational services choices showed the following: 1) It was proven that attribute expectations played a partial mediating role in the influence of expertise and similarity, respectively, on educational services choices. 2) On the influence of trustworthiness, likability, and familiarity on educational services choices, respectively, attribute expectations had a full mediation effect. This research differs from the previous ones, which focused only on consumer satisfaction with educational services offered by private educational institutions in that it covers not only the influences of both WOM source attributes and key component factors of educational services on both educational services choices and satisfaction with such services but also the influence of WOM source attributes on attribute expectations prior to the first visit to a particular private educational institutions, and in turn the influence of such attribute expectations on educational services choices. Most particularly, the significance of this study lies in the fact that in an effort to more clearly explain the causal relationship between WOM source effects and educational services choices a test of the mediating role of attribute expectations was conducted. Although the research seems simple, some theoretical implications can be drawn as follows: WOM message source effects on educational services choices were positive and moreover these positive impacts are likely to be reinforced by means of the mediating variable of attribute expectations.

• Korean Journal of Microbiology
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• v.39 no.2
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• pp.95-101
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• 2003

The total bacterial numbers, Eubacterial community structures and environmental factors which affect bacterial community were estimated monthly using DAPI and fluorescent in situ hybridization monthly, from June to November 2000 to evaluate the correlation between the bacterial community and environmental factors in eutrophic agricultural Masan reservoir in Asan. Average water temperatures varied from 12.3 to $27.5^{\circ}C$, pH 7.5 to 9.0, DO 7. I~12.8 mg/L, COD 6.4~13.0 mg/L, chlorophyll a 30.5~99.0 mg/㎥, SS 7.S~25.7 mg/L, TN 1.748~3.543 mg/L., and TP 0.104~0.581 mg/L, respectively. Total bacterial numbers showed high ranges from 0.4 to 9.6$\times$ $10^{6}$ cells/ml, and these indicated the mesotrophic or eutrophic state. The ratio of Eubacteria to total bacteria was 67.6-88.0%, which was higher than that in other reservoir. The relationships of total bacteria and Eubacteria community were more significant with organic nitrogen (Org-N), and organic phosphorus (Org-P) than with water temperature. Proteobacteria groups showed strongly significant relationships with Org-P and Org-N and significant relationships with water temperature, conductivity, COD, and inorganic nitrogen. C-F group was the most significant with Org-N, and HGC group with water temperature. However, relationships of Chl-a, pH, DO and SS showed no significance with any bacterial community. These results were different from other studies, because of the specific characteristics of Masan reservoir such as old, shallow and eutrophic states. The seasonal variation of bacterial community in Masan reservoir does not seem to depend on phytoplankton dynamics but on storm event and organic materials from watershed and the sediment of reservoir.

• Journal of dental hygiene science
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• v.9 no.1
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• pp.115-120
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• 2009

The purpose of this study was to utilize it as a basic data for local self-government in each region to plan and perform the oral health program targeting children and mothers as guardian. Data had been obtained by using children's oral examination and mothers' self-reported questionnaire method from June 1 to June 30 in 2007 targeting kindergartens where are located in the region of Hwaseong city. The survey was conducted targeting totally 239 people. Its results are as follows. 1. The healthy-tooth rate in the whole children accounted for 79.12%, thus girls were indicated to be a little higher with 80.36% than boys with 78.13%. Carious-tooth rate showed 8.74% for boys and 6.07% for girls. The dental-caries experience treatment rate showed 11.37% for boys and 12.59% for girls. 2. The index of children at age 5, df rate was 39.3% in the whole, thereby having been indicated that boys with 41.3% are higher than girls with 37.2%. Even dft index is showing the higher index in boys with 3.9 than girls with 3.2. 3. As a result of examining mothers' oral-health behavior, mothers with out employment thought the self oral-health state to be good(p = 0.002). In appearance of scaling experience or of periodic dental checkup, a slight difference is being shown according to general characteristics, but wasn't significant. 4. As a result of examining children's oral management, it was indicated that the higher economic level(p = 0.011) and the more in mothers without employment lead to giving a light meal less(p = 0.41). In appearance of children's periodic dental checkup, the higher academic background level(p = 0.047) and the more employment(p = 0.044) led to receiving dental examination.

• Journal of the Korea Concrete Institute
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• v.21 no.4
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• pp.513-521
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• 2009

Recently, the externally prestressed unbonded concrete structures are increasingly being built. The mechanical behavior of prestressed concrete beams with external unbonded tendon is different from that of normal bonded PSC beams in that the slip of tendons at deviators and the change of tendon eccentricity occurs as external loads are applied in external unbonded PSC beams. The purpose of the present paper is therefore to evaluate the flexural behavior by performing static flexural test according to tendon area and tendon force. From experimental results, before flexural cracking, there was no difference between external members and bonded members. However, after cracking, yielding load of reinforcement, ultimate load, and the tendon stress of external members was lower than that of bonded members. For the relationship of load-tendon stress, the increasing of tendon strain was inversely proportional to the initial tendon force. However, even if the initial tendon force was large, the tendon strain with small effective stress was smaller than that with large effective stress. The concrete compressive strain was proportional to the effective stress of external tendon. From the comparison between test results and codes, the ACI-318 could not consider the effect of tendon force or effective stress, and especially the results of ACI-318 were very small, so it was very conservative. And the AASHTO 1994 could be influenced on the tendon area, initial force and effective stress, but as it was made on the basis of internal unbonded tendon, its results were much larger than the test results. For this reason, the new correct predict equation of external tendon stress will be needed.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.3
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• pp.277-284
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• 2011

This study is based on the data of adults between ages of 19~65 yrs of the National Health and Nutrition Survey 4th in year of 2009, which includes symptoms of temporomandibular disorder within gender and age. Subjects included in this study were 2,738 males and 3,427 females, total of 6,165. All statistical analysis was measured by Window SPSS 17.0K Program (SPSS Inc., Chicago, USA). Prevalence of analysis of gender, age, and symptoms of temporomandibular disorder was measured by descriptive statistics, and in order to find relationship among gender, age, and symptoms of temporomandibular disorder was based on crosstabulation analysis. As results, prevalence of TMJ sound was 10.1%, of TMJ pain was 1.5%, and of TMJ limitation was 2.0%. Among the three symptoms of temporomandibular disorder, subjects who have at least one symptom was 1.2%. Prevalence of TMJ sound, of TMJ pain, and of TMJ limitation in female were 10.7%, 1.8% and 2.2%, respectively, which were greater than in male 9.3%, 1.2% and 1.6% respectively but it was stastically insignificant (p>0.05). Prevalence of TMJ sound, of TMJ pain, and of TMJ limitation in ages between 19~24 yrs were 18.7%, 3.4% and 4.2% respectively, which were higher than any other ages (p<0.05). Also prevalence of having at least one symptom of temporomandibular disorder, at least two, and three all were higher in females but stastically insignificant (p>0.05). On the other hand, prevalence of having at least one symptom of temporomandibular disorder, at least two, and three all were greater in age below 45 yrs and was stastically significant (p<0.05).