• Korean journal of applied entomology
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• v.28 no.3
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• pp.113-119
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• 1989

Larval development and adult oviposition of the Oriental tobacco budworm, Heliothis assulta were examined with tobacco leaves sprayed with aqueous or ethanolic extracts from ten selected wild plant species. High larval mortality was observed with extracts from Rhamnus davurice. Persicaria hydroPiPer, Forsythia koreana, Trifolium repens, Styrax japonica, Ginkgo bi/oba, and vilis amurensis. Most of larval mortality occurred during first and second instar, apparently due to antifeeding effects of plant extracts. These extracts also prolonged developmental period of survived larvae and increased the number of larval molts. Oviposition was not affected as much as the larval mortality, but Rhamnus davurice and Styrax jaPonica extracts reduced the number of eggs laid by more than fifty percent.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.204-210
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• 2016

This paper presents an experimental analysis of the growth and oxidation processes of soot particles generated in an isooctane diffusive laminar flame due to incomplete combustion. The effects of iron-based diagnostics were employed to measure the elastic scattering light from soot particles in a flame at different flame heights, and the differential scattering coefficients were calculated through a calibration process. The growth and oxidation of soot particles in flame was investigated by comparing differential scattering coefficients, and the soot volume fraction was seen to decrease in the soot oxidation process. In the same manner, the differential scattering coefficients were calculated for iron-based fuel-additive seeded flame, and these coefficients were revealed to be smaller than those obtained in the fuel-additive unseeded flame. In addition, transmission through the radial direction of the flame was measured, and transmission in the soot oxidation regime was approximately 5% higher for the seeded flame. The propensity of the data coincided well with the differential scattering coefficients, and it can be concluded that the iron component of the fuel additive plays a crucial role as a catalyst, which eventually enhanced soot particle oxidation.

• Journal of Sericultural and Entomological Science
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• v.3
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• pp.23-28
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• 1963

The RNA content of fertilized egg of Bombyx mori was shown a continuing great increase reaching peak at the 5th day after egg laying and a slight decrease there after. Such a change of RNA content is considered to be directly associated with the formation and development of egg embryo of silk worm. (2) The RNA content of nonfertilized egg is much less than that of fertilized one at first day of egg laying and it increased slightly until 4 th day after egg laying then decreased. (3) The RNA content of fertilized egg irradiated by gamma-ray (3,000 r) was shown a slight increase until 2nd day after irradiation, but no change was observed there after. This fact shows that irradiation suppressed the biosynthesis of RNA silk worm egg. (4) The RNA content of HCl treated silk worm egg was shown a continuing steep rise until 7 th day after the acid treat, while no change was observed in the non-treated egg. The RNA content of HCl treated egg with irradiation of gamma-ray (1,500 r), decreased until 3 rd day after irradiation in contrast to that of non-irradiated group, but it increased rapidly from 4 th day until 7 th day after acid treating.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.551-559
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• 1992

These studies were conducted to investigate the biological effects of buprofezin 25% WP on the adult of the brown planthopper (BPH) and its control effects on the BPH population, when buprofezin was treated on different days after the introduction of the BPH adult to the potted rice. Also age structures of the BPH population at the time of buprofezin treatment were observed. The results were as follows: Buprofezin (7.0 g a.i./l0 a) could reduce the longevity and fecundity of the newly emerged female but did not affect the biology of older female, and it did not affect the biology of the male. The larval densities at the time of buprofezin treatment was reduced to nearly zero after treatment. The higher the residual effect and the proportion of larvae at the time of buprofezin treatment were, the higher its con¬trol effect on the BPH population was. In case of buprofezin 7.0 g a.i./l0a treatment, the time interval of treatment that could show the highest control effect was about 10 days (from 18 days after the adult introduction to the adult emergence days of next generation).

• The Korean Journal of Pesticide Science
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• v.13 no.1
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• pp.54-61
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• 2009

EPN-resistant diamondback moth were tested the developmental characteristics, longevity, fecundity and synergistic effect with synergists when treated with the bistrifluron, an inhibitor of chitin synthesis. Inhibition rate of egg hatch was below at the recommended concentration (50 ppm) to the EPN-resistant strain than EPN-non selected strain, however, mortality within 24hr after hatching was showed as 50-60%. They did not show the difference between two strains. Mortality of larval instars were showed effective to two strains with no difference. Inhibition rate of emergence did not show any effect when treated with pupae. Moreover, they did not affect to the longevity and fecundity. When bistrifluron was treated at 50 ppm to the adult, however, longevity and fecundity was decreased with no difference between two strains. Bistrifluron to the EPN-resistant strain showed synergistic effect as high as 137.7 and 73.1 folds with synergist such as PBO (microsomal oxidase inhibitor) and polyoxin B (chitin synthetase inhibitor), respectively.

• Applied Biological Chemistry
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• v.20 no.2
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• pp.205-209
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• 1977

The pool size of plasma glucose, turnover rate and other concerned items for glucose metabolism in normal laying hen were investigated by a single-injection method using $U-C^{14}-glucose$. The 11.6 nCi of pure dose was injected to a hen normally fed through the wing vein. The glucose concentration in plasma sample taken at 5 minutes after injections was 214mgper 100ml. From the plottings of logarithmic standard specific activities of plasma taken from 5 to 120 minutes against the time after injection and from the regresion analysis, metabolic states were determined. The pool size was 1.07g, turnover rate was 0.024 per minute, turnover time was 41 minutes, utilization rate was 26mg/min. (0.83 g/hr/kg B.W. 3/4) and glucose space(extracellular fluid volume) was 25.3 per cent of body weight. The values obtained from. 10-50 minutes samples were similar to those described above, which we from 5-120 minutes samples.

• 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.32 no.2
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• pp.123-128
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• 1993

The comparative toxicities of selected acaricides against the twospotted spider mite, Tetranychus urticae, were investigated. The ovicidal and adulticidal activities of selected acaricides were examined under different developmental stages. Fenpyroximate showed high activity throughout all developmental stages of mites. The oviposition inhibition effect of fenpyroximate was more highly effective than that of cyhexatin. At 100 ppm concentration, the effect of fenpyroximate on the residual oviposition inhibition was persistant during 25 days with 85% level, while the effect of cyhexatin gradually decreased, and then decreased to 40% at 25 days after treatment. Fenpyroximate at 100 ppm showed 100% knockdown activity within 3 hour while cyhexatin showed only 91% knockdown activity within 24 hours after treatment. Most of selected acaricides had no systemic activity, but metasystox at 800 ppm had 100% of the systemic activity at 24 hours after treatment. For the influence of temperature on the activity, fenpyroximate showed stable activity and no temperature-dependent in comparison with other selected adaricides.

• Journal of Life Science
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• v.22 no.7
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• pp.880-888
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• 2012

This study was carried out to investigate the effects of inuloprebiotics (INPs), an alternative antibacterial growth promotor, from Jerusalem artichoke extract (Helianthus tuberosus L.) on egg production and quality in Hyline brown laying hens. The hens were divided randomly into four treatment groups and housed in individual cages for 10 weeks: a control group (0 ppm INP) (T1), 450 ppm (T2), 600 ppm (T3), and 750 ppm (T4). Egg production, egg weight, Haugh unit, eggshell thickness, and breaking strength were significantly higher in all of the INP-treated groups compared with the control (p<0.05). Egg cholesterol was highest in the T1 group and decreased with INP addition from 15.04 to 17.98% (p<0.05). Compared with the T1 group, triglycerides in the blood and in total cholesterol decreased significantly in groups T2, T3, and T4 by 21.71-24.07% and 27.17-30.36%, respectively (p<0.05). The growth of cecum Bifidobacterium and Lactobacillus was stimulated in groups T2, T3, and T4 compared with T1, whereas the growth of Escherichia and Salmonella was clearly inhibited (p<0.05). The results suggest that the addition of 450 ppm INP to the diet of laying hens can improve egg production and egg quality.

• KOREAN POULTRY JOURNAL
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• v.38 no.3 s.437
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• pp.73-75
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• 2006

닭의 개체는 개량에 의해 경제능력은 해마다 향상되었지만, 주위환경은 발전되지 못하고 상대적으로 감소되어 왔다. 양계사업은 경제성을 감안하여 영양, 질병, 사양, 환경 등 전반적으로는 닭이 생활하는데 점점 더 열악한 환경이 되어가고 있다. 사회적 환경이 면역능력향상 보다는 면역억제 요인이 더 많이 존재한다. 또한 가금류 사육이 늘고, 특정 질병들이 사회문제화 되면서 그 피해 또한 닭 사육 농가에도 피해가 발생하는 상황이 되었다. 사회적으로는 안전한 축산물과 친환경적인 축산물을 요구하다보니 생산원가는 점점 높아지고 FTA와 같은 국제무역협상이 더욱더 우리 축산인들의 목을 죄어 오고있는 실정이다. 이런 상황에서 양계산물은 점점 설자리를 잃어가고 소비위축과 생산의욕 저하로 인하여 점점 더 어려움에 처해 있는게 우리 양계인의 현실이다. 이런 현실에서 생산원가 절감만이 우리 양계인이 살아남는 길이 아닌가 생각한다. 환절기에는 닭 스스로 자기면역 능력을 키우기에는 한계가 있으므로 사료에 영양제나 면역능력을 향상시키는 물질을 첨가하는 것 또한 한 예가 될 것이다. 해마다 겪는 일이지만 늘상하는 일이라고 치부하고는 실천하지 않아 손해를 보는 일이 종종 일어난다. 이것을 조금이나마 줄여보고자 한다.