• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.2
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• pp.35-39
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• 2015

The developmental responses of insects to temperature are important considerations in gaining a better understanding of their ecology and life histories. Temperature-dependent phenology models permit examination of the effects of temperature on the geographical distributions, population dynamics, and management of insects. Measurements of insect developmental and survival responses to temperature pose practical challenges that depend on the chosen modality, variability among individuals, and high mortality rates near the lower and upper threshold temperatures. Different temperature levels can significantly affect larval development of Eurema hecabe. The development of E. hecabe reared on leaves of Lespedeza cuneata was investigated at three temperature regimes (20, 25, and 30℃), a relative humidity of 60%, and a light:dark photoperiod of 14:10 h. The developmental time from larva to adult was 34.3, 20.6, and 17.9 d at temperatures of 20, 25, and 30℃, respectively. Pupal rate was 47.6%, 47.6%, and 61.9% at temperatures of 20, 25, and 30℃, respectively. The developmental threshold temperature estimated from larva to pupae was 8.1℃ with 381.7 degree-days. There is an increasing need for a standardized manual for rearing this butterfly species based on adequate knowledge of its ecology.

• The Korean Journal of Soil Zoology
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• v.5 no.2
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• pp.119-123
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• 2000

Effect of fluctuating temperatures on the development of the immature beet armyworm, Spodoptera exigua (H bner), was analyzed. At constant rearing temperature regimes, the estimated developmental threshold temperatures were varied among stages and instars, but had an average 13$^{\circ}C$ from egg hatch to adult emergence. Based on the 13$^{\circ}C$ threshold temperature, we set up three different rearing temperature regimes having the same day-degrees. Two fluctuating temperature regimes changed significantly the developmenta1 period expected by the constant rearing temperature regime. Under the same thermophase temperature (25$^{\circ}C$), the thermocycling regime with the higher cryophase temperature (10$^{\circ}C$) decelerated the developmental rate probably by lowering temperature limit thor development, but that with the lower cryophase temperature (5$^{\circ}C$) gave a negative developmental effect.

• Korean journal of applied entomology
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• v.43 no.2
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• pp.111-116
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• 2004

The development of Aphis gossypii was studied at various constant temperatures ranging from 15 to 35$^{\circ}C$, with 60-70％ RH, and photoperiod of 16：8 (L：D h). Mortality of A. gossypii was high in the early developmental stages, and at high temperatures. The total immature developmental period ranged from 4.6 to 11.5 days. The lower developmental threshold temperature and effective cumulated temperature for all immature stages were 5.0$^{\circ}C$ and 106.8 degree-day, respective. The nonlinear shape of temperature-dependent development was well described by the modified Sharpe and DeMichele model. The normalized cumulative frequency distributions of developmental period for each life stage were fitted to the three-parameter Weibull function.

• The Korean Journal of Ecology
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• v.6 no.1
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• pp.55-65
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• 1983

The authors reared the ash-gray leaf bug, Piesma maculata in the growth cabinet controlled as temperature groups of $15, 20, 25, 30, 40^{\circ}C$under condition of photoperiod 16L:8D, light intensity $510{\pm}240$ lus, relative humidity $65{\pm}3%$, and analyzed the effects of temperature on the development of the insect. The results are summarized as follow: There are highly significant differences the developmental periods for the temperature groups, and between the developmental periods for the developmental stages. The egg in the temperature of 15 and $40^{\circ}C$ was hatched, but the ecdysis was impossible. The thermal threshold was $12.34^{\circ}C$and the upper lethal temperature $40.39^{\circ}C$. The total developmental periods of egg to adulate in the temperature of 20, 25, 30 and $35^{\circ}C$are 40.52, 22.37, 15.91 and 13.00 days, respectively. That is, the developmental period was decreased, as the temperature was increased. In the developmental period for the developmental stages, the developmental period of egg stage was longer than that of 25, 30 and $35^{\circ}C$, and that of 25。C was longer than that of $35^{\circ}C$. But ther was not significant differences between the developmental periods for the other temperature group. The rate of hatch at$20^{\circ}C$is the greater value as 90%, and the rates of 25, 30 and $35^{\circ}C$ are 79, 79 and 67%, respectively. That is the rate of hatch was decreased, as the temperature was increased. The mortality in the temperature of $35^{\circ}C$ is the greatest value as 68%, and those of 30, 25 and $20^{\circ}C$are 59, 59 and 41%, respectively. That is, the mortality was increased, as the temperature was increased. There was not significantly differences between the developmental period of female and male.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.387-394
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• 2013

The developmental times of mealworm beetle larvae, Tenebrio molitor were studied at six temperatures ranging from 15 to $30^{\circ}C$ with 60~70% RH, and a photoperiod of 14L:10D. Mortality of larval period was very low at 17 and $20^{\circ}C$ but did not die over $22^{\circ}C$. Developmental time of larva was decreased with increasing temperature. The total developmental time of T. molitor larvae was longest at $17^{\circ}C$ (244.3 days) and shortest at $30^{\circ}C$ (110.8 days). Egg and larvae were not developed at $15^{\circ}C$. The lower developmental threshold and effective accumulative temperatures for the total larval stages were $6.0^{\circ}C$ and 2564.1 degree-days, respectively. The relationship between developmental rate and temperature was fitted by a linear model and nonlinear model of Logan-6($r^2$=0.95). The distribution of completion of each development stage was well described by the 2-parameter Weibull function ($r^2$=0.8502~0.9390).

• Korean journal of applied entomology
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• v.49 no.3
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• pp.199-204
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• 2010

The seasonal fluctuation of the large 28-spotted lady beetle, Henosepilachna vigintioctomaculata (Motschulsky), was observed in potato fields of Gangneung region, Gangwondo Province. The effects of their leaf consumption over a 24 hour period and developmental periods by different temperatures were investigated, and then the developmental threshold (DT) and effective cumulative temperature (ET) of each stage were calculated. Various developmental stages of H. vigintioctomaculata were captured in the fields from May to September, with three peaks in late May, late June, and late August. Leaf consumption by larval stages increased with the development of instar. The 4th instar larvae consumed potato leaves much more than other stages. Egg hatchability and emergence rate of H. vigintioctomaculata were lower at $10^{\circ}C$ and $30^{\circ}C$, but higher at around $20{\sim}23^{\circ}C$. The developmental periods of each stage became shorter as temperature increased; 90 days at $10^{\circ}C$, 40 days at $20^{\circ}C$ and 25 days at $25^{\circ}C$. Base on developmental velocity to temperature, calculated DT and ET were $7.3^{\circ}C$ and 83.

• Korean journal of applied entomology
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• v.52 no.1
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• pp.5-12
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• 2013

The Hawaiian beet webworm (Spoladea recurvalis) is one of the serious insect pests found on red beet (Beta vulgaris var. conditiva) in Korea. The study was conducted to investigate the development period of S. recurvalis at various constant temperatures, 15.0, 17.5, 20.0, 22.5, 25.0, 27.5, 30.0, 32.5 and $35.0^{\circ}C$, with $65{\pm}5%$ RH and a photoperiod of 16L:8D. The developmental period from egg to pre-adult was 51.0 days at $17.5^{\circ}C$ and 14.6 days at $35.0^{\circ}C$. The developmental period of S. recurvalis was decreased with increasing temperature. The relationship between the developmental rate and temperature was fitted well by linear regression analysis ($R^2{\geq}0.87$). The lower developmental threshold and effective accumulative temperature of the total immature stage were $10.4^{\circ}C$ and 384.7 degree days, respectively. The nonlinear relationship between the temperature and developmental rate was well described by the Lactin model. The relationship between the cumulative frequency and normalized distributions of the developmental period for each life stage were fitted to the Weibull function with $R^2=0.63{\sim}0.87$.

• Journal of Life Science
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• v.10 no.1
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• pp.1-6
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• 2000

Larval development, adult longevity and oviposition of the beet armyworm, Spodoptera exigua H bner was studied at 16, 20, 25 and 3$0^{\circ}C$ with a 16L: 8D photoperiod. Egg hatchability of S. exigua was the highest at 3$0^{\circ}C$ and reduced with decreasing temperature. Egg period was the shortest at 3$0^{\circ}C$ and prolonged with decreasing temperature. Percent pupation was became higher at higher temperature form 23.2% to 94.0%. Developmental period of larva was the shortest at 3$0^{\circ}C$, but extended with decreasing temperature. Adult emergence ratio was the highest at 3$0^{\circ}C$ and reduced with decreasing temperature. The mean pupal period was 35.2, 14.4, 7.8 and 5.0 days at 16, 20, 25 and 3$0^{\circ}C$, respectively. Relationships between constant temperature and the developmental velocity of egg, larva and pupa were linear. Developmental threshold temperature seems to be 13.3 8$^{\circ}C$ for egg, 14.02$^{\circ}C$ for larva, 14.09$^{\circ}C$ for pupa, and 13.84$^{\circ}C$ for egg the adult. Estimated value of the total effective temperature for completing each stage was 36.89 day-degree for egg, 155.72 day-degree for larva, 79.20 day-degree for pupa, and 273.41 day-degree for egg to adult. Female longevity varied to temperature from 11.4 days at 16$^{\circ}C$ to 5.8 days at 3$0^{\circ}C$, and male longevity was longer than that of female. Preoviposition period was the shortest at 3$0^{\circ}C$, but prolonged with decreasing temperature. It was about 2.7 times longer at 16$^{\circ}C$ than that at 3$0^{\circ}C$. Number of eggs per female was the highest at $25^{\circ}C$, followed by 20, 30 and 16$^{\circ}C$.

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.4
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• pp.231-245
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• 2017

The purpose of this study is to analyze the trend line through scatter diagram analysis on correlation between SNS addiction tendencies and learning attitudes, figure out the knee point influencing learning attitudes negatively in detail, and examine influence among subareas. To address the goal, study questions are formulated as follows. First, this author did screening on the data of variables measured and analyzed descriptive statistics. Second, this researcher produced the trend line by drawing a scatter diagram in order to analyze correlation between SNS addiction tendencies, withdrawal symptoms, excessive communication, and excessive time wasting, and learning attitudes exploratorily. Third, to explore correlation between self-evaluation, learning participation, and developmental attitudes, the subfactors of learning attitudes related to SNS addiction tendencies, this author drew a scatter diagram and analyzed the threshold of positive and negative correlation. To verify the study questions, the SNS addiction tendency scale and learning attitude scale were applied to 301 university students in Chungcheong area. According to the study results, first, their learning attitudes are influenced by SNS addiction tendencies, excessive communication and excessive time wasting, and they are not influenced by withdrawal symptoms that much. Second, excessive communication, a factor of SNS addiction tendencies, and self-evaluation and developmental attitudes, factors of learning attitudes, show positive correlation to some extent and indicate negative correlation after the threshold. However, excessive communication and learning participation are found to show no correlation. Third, according to the results of examining correlation with learning attitudes by dividing them into excessive communication and excessive time wasting groups with the knee point of 1.40, as the symptom of excessive communication is found more, it influences self-evaluation, learning participation, developmental attitudes, and learning attitudes more negatively in general. The result of this study is expected to provide foundational material necessary to develop educational programs to prevent undergraduates' excessive SNS use and SNS addiction which can be used in the scenes of counseling or education.

• Genes and Genomics
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• v.40 no.11
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• pp.1149-1155
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• 2018

Epileptic encephalopathies are genetically heterogeneous disorders which leads to epilepsy and cause neurological disorders. Seizure threshold 2 (SZT2) gene located on chromosome 1p34.2 encodes protein mainly expressed predominantly in the parietal and frontal cortex and dorsal root ganglia in the brain. Previous studies in mice showed that mutation in this gene can confers low seizure threshold, enhance epileptogenesis and in human may leads to facial dysmorphism, intellectual disability, seizure and macrocephaly. Objective of this study was to find out novel gene or novel mutation related to the gene phenotype. We have identified a large consanguineous Saudi family segregating developmental delay, intellectual disability, epilepsy, high forehead and macrocephaly. Exome sequencing was performed in affected siblings of the family to study the novel mutation. Whole exome sequencing data analysis, confirmed by subsequent Sanger sequencing validation study. Our results showed a novel homozygous mutation (c.9368G>A) in a substitution of a conserved glycine residue into a glutamic acid in the exon 67 of SZT2 gene. The mutation was ruled out in 100 unrelated healthy controls. The missense variant has not yet been reported as pathogenic in literature or variant databases. In conclusion, the here detected homozygous SZT2 variant might be the causative mutation that further explain epilepsy and developmental delay in this Saudi family.