• The Korean Journal of Pesticide Science
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• v.3 no.2
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• pp.74-80
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• 1999

These studies were carried out to investigate the effects of nonsteroidal ecdysone agonist, tebufenozide on embryonic and postembryonic development of sycamore lace bug, Corythucha ciliata. Tebufenozide exhibited ovicidal activity($LC_{50}=4.0$ ppm). Susceptibility of each instar nymphs to tebufenozide was nearly same($LC_{50}=2.3{\sim}6.0$ ppm). The tebufenozide treatment in the final instar affected the emergence, longevity and fecundity of surving adults significantly. Tebufenozide applied at high concentration (10 ppm) to younger adults delayed prioviposition period, and decreased adult longevity, the number of eggs laid per female and hatchability. The treatment also inhibited the ovarian development of the female adults.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.159-162
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• 1998

Effect of temperature on oviposition and developmental period of Oulema oryzae K. on riceplant were investigated. With the given set of temperatures of 15, 20, 23, 25, and 28"C, developmentalperiod from egg to adult emergence was shorten as temperature increased. Average number of eggs perfemale 0. oryzae increased as temperature increased from 15$^{\circ}$C to 23"C, then decreased at 25$^{\circ}$C and 28"C. Based on this result, developmental threshold temperatures for egg was estimated to be 6.4"C. Totaleffective temperatures above the thresolds required for hatching were estimated to be 75.8 degree-daysfor egg. It seemed that the optimum temperature for oviposition of Oulema oryzae on rice plant was 23"C.a oryzae on rice plant was 23"C.quot;C.

• Human Ecology Research
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• v.53 no.3
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• pp.293-307
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• 2015

Social commerce has a large impact on the emergence of the concept of society and individual lives that is recognized as one of the most important business areas in the Internet environment. A marketing agency, Trend Monitor (http://www.trendmonitor.co.kr), conducted a survey on social commerce usage and satisfaction level; subsequently, we used survey result data from 221 adult males and females for our research sample. Data analyses were conducted by reliability test, confirmatory factor analysis, t -test or one-way analysis of variance, and structural equation model (SEM) with IMB SPSS ver. 21.0 and ver. AMOS ver. 21.0. This study focused on multi-dimensional consumer innovativeness and found three elements of acceptability, competence, and distribution. Empirical verification through SEM presented data that suggests the three consumer innovativeness factors have a direct positive effect on social commerce that causes factors to indirectly affect satisfaction levels. This study indicated that the main consumption patterns in modern society take advantage of social commerce and satisfaction by improving a market economy to promote restoration. First, this study considers consumer innovativeness to have three factors. Secondly, research results help to understand relations between consumer innovativeness, use and satisfaction with social commerce that can help the social commerce industry establish effective market strategies through consumer innovativeness. The conclusion discusses implications for academic research and marketing strategies.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.2
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• pp.1-5
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• 1980

Comparisons were made between pubescent and smooth leaved cultivars or lines for the brown planthopper feeding preference, adult emergence percent, nymphal period, grain yield and brown rice recovery percent, and found that there were no significant differences of the traits tested between smooth and pubescent.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.91-97
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• 2002

This study was conducted to determine the effects of temperature and food onthe nymphal development and adult longevity of the green virid bug, Cyrtorhinus lividipennis Router. Nymphal period was 13.2 to 13.7 days at 24$^{\circ}C$, 10.4 to 10.9 days at 28$^{\circ}C$, and 9.0 to 9.3 days at 32$^{\circ}C$. Number of eggs predated by nymph was 10.6-14.3 at 24$^{\circ}C$, 7.5-9.2 at 28$^{\circ}C$, and 5.8-7.5 at 32$^{\circ}C$. Amount of predation was highest on BPH, followed by SBPH, WBPH, and GLH. Number of nympal moulting was mostly four times (55-75%) followed by three times (25-45%), regardless of temperature and food. Percent emergence rate was 52-70%, 48-66% and 22-38% at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively, showing a tendency to decrease with increasing temperature, and was affected by foods. Adult longevity, when supplied with one food, was 19.8 to 22.5 days at 24$^{\circ}C$, 15.6 to 17.0 days at 28$^{\circ}C$, and 10.3 to 11.7 days at 32$^{\circ}C$. There was no significant difference among foods in terms of adult longevity, but it tended to be slightly longer when provided with four foods than with one food. Number of eggs predated by an adult, when supplied with one food, was 35.7-54.2, 31.6-44.6 and 18.1-28.2 at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively. It was highest on BPH, followed by SBPH, WBPH and GLH regardless of temperature. Number of egg Predated by an adult, when supplied with four foods, was 4.0-28.9, 2.9-29.0 and 17-13.6 at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively, and was significantly different among foods supplied. The results suggest that the significantly different predation amount by adult was due to food preference amoung the different foods.

• Korean Journal of Environmental Biology
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• v.40 no.2
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• pp.187-198
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• 2022

In this study, Telenomus remus Nixon (Hymenoptera: Scelionidae) was first reported as a natural enemy of the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) egg collected from corn fields in Korea, and its biological characteristics was studied. Based on morphological and molecular analysis, the parasitoid emerged from S. frugiperda eggs was identified as T. remus. We found that T. remus can attack the eggs of S. frugiperda, Spodoptera litra and Spodoptera exigua under a laboratory condition. The longevity of T. remus female adult was longer than that of male adult. The egg-to-adult period of T. remus was not affected by the host age and sex. T. remus female adult laid at least 1-3 eggs a day to a maximum of 37 or more eggs, and the most oviposited on the 3^rd to 4^th day after emergence. The host preference for oviposition of T. remus adult was high in the order of S. litura>S. exigua>S. frugiperda. T. remus preferred to parasitize 1- and 2-day-old host egg rather than 3-day-old host egg. When compared to the sex ratio of T. remus progeny, the rate of female progeny was higher at the initiation time of oviposition, while the proportion of male progeny increased significantly with female adult age, especially after 8-day-old adult. This information may be useful for improving T. remus mass rearing system and developing a biological control program to control S. frugiperda.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.343-352
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• 2011

The developmental period of Laodelphax striatellus Fallen, a vector of rice stripe virus (RSV), was investigated at ten constant temperatures from 12.5 to $35{\pm}1^{\circ}C$ at 30 to 40% RH, and a photoperiod of 14:10 (L:D) h. Eggs developed successfully at each temperature tested and their developmental time decreased as temperature increased. Egg development was fasted at $35^{\circ}C$(5.8 days), and slowest at $12.5^{\circ}C$ (44.5 days). Nymphs could not develop to the adult stage at 32.5 or $35^{\circ}C$. The mean total developmental time of nymphal stages at 12.5, 15, 17.5, 20, 22.5, 25, 27.5 and $30^{\circ}C$ were 132.7, 55.9, 37.7, 26.9, 20.2, 15.8, 14.9 and 17.4 days, respectively. One linear model and four nonlinear models (Briere 1, Lactin 2, Logan 6 and Poikilotherm rate) were used to determine the response of developmental rate to temperature. The lower threshold temperatures of egg and total nymphal stage of L. striatellus were $10.2^{\circ}C$ and $10.7^{\circ}C$, respectively. The thermal constants (degree-days) for eggs and nymphs were 122.0 and 238.1DD, respectively. Among the four nonlinear models, the Poikilotherm rate model had the best fit for all developmental stages ($r^2$=0.98~0.99). The distribution of completion of each development stage was well described by the two-parameter Weibull function ($r^2$=0.84~0.94). The emergence rate of L. striatellus adults using DYMEX$^{(R)}$ was predicted under the assumption that the physiological age of over-wintered nymphs was 0.2 and that the Poikilotherm rate model was applied to describe temperature-dependent development. The result presented higher predictability than other conditions.

• Korean journal of applied entomology
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• v.60 no.2
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• pp.255-262
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• 2021

The potato tuber moth, Phthorimaea operculella (Zeller) has been known as a quarantine pest of potato. This study investigated inhibition doses of electron beam irradiation (EBM) by comparing their effects on the development and reproduction and DNA damage of the insect pest. Eggs (0-12 h old), larvae (3^rd and 5^th instar), pupae (less than 1 d old after pupation) and adults (less than 1 d old after emergence) were irradiated with increasing doses of EBM. The EBM with 150 Gy could not completely prevent the hatchability of eggs and pupation of the hatched larvae. The hatchability from the irradiated eggs were 19.3%. However, adult emergence from the irradiated eggs were completely inhibited. When 3^rd and 5^th instar larvae were irradiated at 100 Gy, the adult emergence from the irradiated larvae and the fecundity of the adults were completely inhibited. When pupae and adults were irradiated at 300 Gy and 400 Gy, respectively, the hatchability of the F₁ eggs was completely inhibited. The alkaline comet assay on the level of DNA damage by EBM in P. operculella adults indicates that the EBM increased DNA damage level in a dose-dependent manner, and the damage was repaired in a time-dependent manner. These results may recommend EBM of 150 Gy as a phytosanitary treatment for P. operculella. However further confirmative study is required for the practical application of this EBM dose for P. operculella disinfestation.

• Korean Journal of Clinical Pharmacy
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• v.27 no.1
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• pp.22-29
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• 2017

Objective: Infection is very common in the elderly, so there is a high prevalence of antibiotics use among this population. Especially, due to the emergence of resistant bacteria, the use of vancomycin is growing. The purpose of this study was to evaluate risk factors associated with vancomycin-induced nephrotoxicity in elderly patients. Methods: The subjects of this study were patients over 18 years old who received intravenous vancomycin in a general hospital located in Gangneung-si, Korea between August 1, 2013 and July 31, 2015. Data collection regarding vancomycin use and baseline characteristics was conducted using computerized hospital database. Logistic regression analysis was used to identify risk factors associated with vancomycin-induced nephrotoxicity. Results: A total of 290 patients were finally included, and 191(66%) out of these patients were age 65 or older. The incidence of vancomycin-induced nephrotoxicity was 11.0%, 12.6%, and 7.0% in the all adult patients, the elderly patients, and the non-elderly patients, respectively. There were significant differences in comorbidities between patients with nephrotoxicity and patients without nephrotoxicity in the all adult patients, and there were significant differences in vancomycin duration, comorbidities, and number of nephrotoxic agents between patients with nephrotoxicity and patients without nephrotoxicity in the elderly patients. However, according to the logistic regression analysis, there was no significant risk factor that increases the incidence of vancomycin-induced nephrotoxicity in all three age groups. Conclusion: There were no differences in risk factors that increase the incidence of vancomycin-induced nephrotoxicity between all adult patients, elderly patients, and non-elderly patients. Further studies with larger sample sizes to identify risk factors associated with vancomycin-induced nephrotoxicity in the elderly to improve the outcome of pharmacotherapy are required.

• Korean journal of applied entomology
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• v.43 no.4 s.137
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• pp.275-279
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• 2004

This study compared the biological characteristics, nymphal development, adult longevity, and oviposition of the bean bug, Riptortus clavatus Thunberg, in fibrous nylon and glass-tube in the insectary at $28{\pm}2^{\circ}C$ and 16L:8D of photoperiod. Nymphal duration in the fibrous nylon-tube was 1 day longer than in the glass tube; the difference was attributed to the developmental duration of the fifth instar. Percent emergence in the fibrous nylon-tube was $64\%,\;8\%$ higher than in the glass tube ($56\%$). In the fibrous nylon-tube, adult longevities for female and male were 4.1 times and 6.0 times higher than those in the glass tube. Preoviposition period was 1 day longer in the fibrous nylon-tube than that in the glass tube. The total number of eggs laid was 3.5 times more in the fibrous nylon-tube than in the glass tube. The oviposition duration lasted about 30 days for the bean bug in the fibrous nylon-tube and about 8 days for those in the glass. Accordingly, the fibrous nylon-tube was found more conducive than the glass tube for determining the biology of bean bug.