• Journal of Sericultural and Entomological Science
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• v.30 no.2
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• pp.96-104
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• 1988

Vitellin, the major yolk protein of the silkworm, Bombyx mori was pruified, and its immunological properties and the quantitative changes during embryogenesis were studied. The ovary transplantation into male hosts was also carried out to find its effect on the yolk protein synthesis. The pupal vitellogenin and the egg vitellin of Bombyx mori were purified by DEAE-cellulose column chromatography. These two female specific proteins showed the same mobility in the polyacrylamide gel electrophoresis and the same reaction in the double immunodiffusion test. The immunological identity was also observed between the vitellins of Bombyx mori and Bombyx mandarina. The rudimentary ovaries transplanted into the male hosts of silkworms produced eggs without vitellin, indicating that the yolk precursors synthesized in other female organ beyond the ovary were necessary to produce vitellins. The major yolk protein, vitellin was disintegrated and utilized mostly during late stage of embryogenesis. It was different characteristics from the egg specific protein, which was utilized continuously from the early embryonic stage.

• Korean journal of applied entomology
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• v.55 no.2
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• pp.149-160
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• 2016

Temperature-dependent development and fecundity of apterious Rhopalosiphum padi (L.) (Hemiptera: Aphididae) were examined at six constant temperatures (10, 15, 20, 25, 30 and $35{\pm}1.0^{\circ}C$, RH 50-70%, 16L:8D). Development time of nymphs decreased with increasing temperature and ranged from 42.9 days at $10^{\circ}C$ to 4.7 days at $30^{\circ}C$. The nymphs did not develop until adult at $35^{\circ}C$ because the nymphs died during the 2nd instar. The lower threshold temperature and thermal constant of nymph were estimated as $8.3^{\circ}C$ and 101.6 degree days, respectively. The relationships between development rates of nymph and temperatures were well described by the nonlinear model of Lactin 2. The distribution of development times of each stage was successfully fitted to the Weibull function. The longevity of apterious adults decreased with increasing temperature ranging from 24.0 days at $15^{\circ}C$ to 4.3 days at $30^{\circ}C$, with abnormally short longevity of 11.1 days at $10^{\circ}C$. R. padi showed the highest fecundity at $20^{\circ}C$ (38.2) and the lowest fecundity at $10^{\circ}C$ (3.9). In this study, we provided component sub-models for the oviposition model of R. padi: total fecundity, age-specific cumulative oviposition rate, and age-specific survival rate as well as adult aging rate based on the adult physiological age.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.277-282
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• 2005

This study was conducted to investigate morphological characteristics and effects of temperature on the development of Piezodorus hybneri on soybean. The unibanded stink bug, Piezodorus hybneri, is a serious insect pest in soybean fields giving damage to seeds in pod and leaves of soybean lowering both quality and yield. Eggs were spherical and laid in two raws on the leaves and pods of soybean plants. Body lengths of females and males were 9.8 mm and 8.7 mm, respectively. Egg hatch rates were better in higher temperature within the range of examined temperatures, which ranged in $81.2{sim}93.2%$. The development periods of eggs at the temperatures of 20, 25, 30 and $35^{\circ}C$ were 10.7, 5.0, 4.0, and 3.0 days, respectively. Mean developmental periods of 1st, 2nd, 3rd, 4th and 5th nymphs at $25^{\circ}C$ were 3.2, 3.4, 3.4, 3.3 and 5.9 days, respectively. Development threshold and effective accumulative temperature were $13.3^{\circ}C$ and 65.5 DD (day degree) for egg stage, $9.9^{\circ}C$ and 322.8 DD for nymph stage, $10.7^{\circ}C$ and 386.4 DD from egg to adult, respectively. Oviposition began from 10 days after emergence at $25^{\circ}C$, and the longevity of female and male were 52.5 and 38.2 days, respectively. Total number of eggs and egg masses laid by a female at $25^{\circ}C$ were 496 and 21.3, respectively, The longevity of adult female was shortened with increasing temperature, whereas the total numbers of eggs laid by a female were decreased.

• Korean journal of applied entomology
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• v.57 no.4
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• pp.261-269
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• 2018

The cowpea aphid Aphis craccivora Koch (Hemiptera: Aphididae) is a polyphagous species with a worldwide distribution. We investigated the temperature effects on development periods of nymphs, and the longevity and fecundity of apterous female of A. craccivora. The study was conducted at six constant temperatures of 10.0, 15.0, 20.0, 25, 30.0, and $32.5^{\circ}C$. A. craccivora developed successfully from nymph to adult stage at all temperatures subjected. The developmental rate of A. craccivora increased as temperature increased. The lower developmental threshold (LT) and thermal constant (K) of A. craccivora nymph stage were estimated by linear regression as $5.3^{\circ}C$ and 128.4 degree-days (DD), respectively. Lower and higher threshold temperatures (TL, TH and TH-TL, respectively) were calculated by the Sharpe_Schoolfield_Ikemoto (SSI) model as $17.0^{\circ}C$, $34.6^{\circ}C$ and $17.5^{\circ}C$. Developmental completion of nymph stages was described using a three-parameter Weibull function. Life table parameters were estimated. The intrinsic rate of increase was highest at $25^{\circ}C$, while the net reproductive rate was highest at $20^{\circ}C$. Biological characteristics of A. craccivora populations from different geographic areas were discussed.

• Korean journal of applied entomology
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• v.62 no.3
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• pp.183-191
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• 2023

After examining the temperature change in berry sawdust during the fermentation period and the developmental characteristics of Protaetia brevitarsis larvae according to the fermentation period, it was found that the fermentation speed was faster than with oak sawdust and a fermentation period of 50-70 days was the most suitable for larval growth. During the fermentation period, the temperature change in sawdust was quickly fermented as berry sawdust passed a high temperature of more than 60℃ in the early stages of fermentation compared to fermentation speed of oak sawdust, and stabilized within 60 days. In individual breeding, the total growth period of P. brevitarsis larvae by fermentation period was the longest at 104.8 days after fermentation for 30 days, which was a significant difference. There was no difference in the growth period between 50 and 90 days of fermentation. Oak sawdust tended to be the same as berry sawdust, but the larval development period was approximately 30 days. The developmental period by larval stage differed greatly between berries and oak sawdust. The weight of larvae according to the fermentation period of sawdust was the lowest after 90 days of fermentation, with a long fermentation period for both berry and oak sawdust, and there was no difference in the 30-70 days fermentation periods. The survival rate was more than 95% in individual breeding, and there was no difference among the fermentation periods. However, in group breeding, the survival rate was lower than that of individual breeding and was lowest at 90 days of fermentation. In group breeding, the ratio of larvae weighing ≥ 2.5 g, which is the standard for shipment, was 85% after 30-70 days of fermentation of berry sawdust, but was lower at 70% after 90 days of fermentation, which was a significant difference. The survival rate with oak sawdust showed the same trend, which was approximately 10% lower than that with sawdust. In addition, the larvae from the berry sawdust weighed > 2.5 g in 40-60 days, while it took 75-105 days with oak-fermented sawdust.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.312-319
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• 2020

Precocious puberty (PP) is defined as the early development of secondary sexual characteristics (before the ages of 8 years in girls and 9 years in boys). The aim of this study is to identify characteristics of the dental maturity in girls with PP that discriminate them from normal healthy girls. This study included 99 girls aged 6 - 8 years with PP and 99 girls without past medical history of same chronological age (control group). The study was performed on 198 panoramic radiographs (99 PP girls, 99 control group girls). Demirjian method was used to evaluate the panoramic radiographs and determine dental maturity. Difference in dental maturity score and tooth formation stages between the two groups were analyzed. The PP group showed significant higher maturity score than control group. Among mandibular teeth, mandibular 2nd premolar and 2nd molar were significantly more mature in the PP group than control group. Logistic regression analysis showed that mandibular 2nd molar was only significant predictor for PP girls.

• Korean journal of applied entomology
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• v.60 no.2
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• pp.215-220
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• 2021

To establish the systematic biological control system for various insect pests in strawberry under plastic houses, we were investigated the biological traits of lesser strawberry aphid, Chaetosiphon minus (Forbes), as a target pest. The lesser strawberry aphid is adapted to low temperatures while examining the availability of and selecting useful natural enemies. The development, survivorship and reproduction of lesser strawberry aphid were evaluated at four constant temperatures (10, 15, 20, and 25℃). The developmental periods of the nymphal stages ranged from 41.7 d at 10℃ to 9.8 d at 25℃. The developmental threshold temperature and degree day of nymphal stages are 5.5℃ and 185 DD. The reproduction rate (R₀) was higher at 20℃ (30.16) than at 25℃ (22.38). The 50 % survival rate and maximum longevity of adult females were 31 d and 59 d at 20℃, and 25 d and 36 d at 25℃, respectively. The average progeny per female was 35 at 20℃, and 26 at 25℃. We confirmed that compared to other strawberry aphids under plastic houses, the lesser strawberry aphid is more adapted to lower temperatures. It is, therefore, necessary to commercialize natural enemies such as syrphid flies with high activity at low temperatures.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.1
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• pp.169-178
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• 2007

Dental crowding is one of the most common type of malocclusions in the mixed dentition. During the period of transition from the primary to the permanent dentition, minor incisor crowding is often present in the normally developing dentitions, but severe crowding can be caused by arch length/tooth size discrepancy. To determine the need for and appropriate timing of treatment for arch-length discrepancies, clinicians must be knowledgeable about normal development. This paper reviewed the literature on normal dental arch development and proper management of dental crowding according to its severity. Due to variations in the timing and the sequence of permanent tooth eruption, management of dental crowding should be specific to the individual patient.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.283-286
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• 2005

This study was carried out to obtain information about a several environmental factors influencing on the bionomical characteristics of Protaetia brevitarsis and Allomyrina dichotoma, which have been used for an important traditional medicinal stuffs. The moisture contents of humus affected the oviposition of P. brevitarsis and A. dichotoma, showing a suitable condition in range of $65{\sim}75%$. Very high or very low moisture condition in humus decreased the egg laying of P. brevitarsis and A. dichotoma, Also, moisture condition of humus was an important factor influencing on the egg and larval survival, egg developmental period, and feeding activity of P. brevitarsis and A. dichotoma.

• Korean journal of applied entomology
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• v.44 no.2
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• pp.139-144
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• 2005

This study was performed to investigate the bionomical characteristics of Protaetia brevitarsis in Korea. The imaginal stage was from in early July and the advent of imagoes was the most frequent in early August. Also few imagoes was entered into the hibernation. The larvae inhibited in humus and the period of larva was all completed in late November. At the stage of the third larva, the larvae entered into the hibernation. The average number of laid eggs was 152, and all periods of each stage - eggs, first, second, third instar larvae and pupa - were shortened in $30^{\circ}C$ than in $25^{\circ}C$. As for the longevity of imagoes, female, reared in individual and in low temperature lived longer than male, in group and in high temperature, respectively.