• Journal of Ecology and Environment
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• 제41권11호
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• pp.318-327
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• 2017

Background: A typical sewage treatment plant is designed for organic and nutrient removal from municipal sewage water and not targeted to eliminate micropollutants such as pesticides, pharmaceuticals, and nano-sized metals which become a big concern for sustainable human and ecological system and are mainly discharged from sewage treatment plant. Therefore, despite contaminant removal by wastewater treatment processes, there are still remaining environmental risks by untreated pollutants in STP (sewage treatment plant) effluents. This study performed aquatic toxicity tests of raw wastewater and treated effluents in two sewage treatment plants to evaluate toxicity reduction by wastewater treatment process and analyze concentration of contaminants to reveal potential toxic factors in STP effluents. Methods: Water samples were collected from each treatment steps of two STPs, and acute and chronic toxicity tests were conducted following USEPA (United States Environmental Protection Agency) and OECD (Organization for Economic Cooperation and Development) guidelines. Endpoints were immobility for mortality and reproduction effect for estrogenicity. Results: Acute $EC_{50}s$ (median effective concentration) of influents for Seungki (SK) and Jungnang (JN) STPs are $54.13{\pm}32.64%$ and $30.38{\pm}24.96%$, respectively, and reduced to $96.49{\pm}7.84%$ and 100%. Acute toxicity reduction was clearly correlated with SS (suspended solids) concentration because of filter feeding characteristics of test organisms. Chronic toxicity tests revealed that lethal effect was reduced and low concentration of influents showed higher number of neonates. However, toxicity reduction was not related to nutrient removal. Fecundity effect positively increased in treated wastewater compared to that in raw wastewater, and no significant differences were observed compared to the control group in JN final effluent implying potential effects of estrogenic compounds in the STP effluents. Conclusions: Conventional wastewater treatment process reduced some organics and nutritional compounds from wastewater, and it results in toxicity reduction in lethal effect and positive reproductive effect but not showing correlation. Unknown estrogenic compounds could be a reason causing the increase of brood size. This study suggests that pharmaceutical residues and nanoparticles in STP effluents are one of the major micropollutants and underline as one of estrogenic effect factors.

• 한국양식학회지
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• 제13권3호
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• pp.245-251
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• 2000

1997년 12월부터 1998년 3월까지 경상북도 영덕~울진 인근 해역의 수심 170~250 m에서 채집된 대게, Chionoecetes opilio의 크기조성에 따른 생태학적인 특징과 성숙에 대해 연구하였다. 갑폭 조성에서, 암컷과 수컷의 주 출현개체군은 각각 70~80 mm (60.1%), 80~90 mm (64.2%) 체급군이었다. 갑장 및 갑폭의 관계 (암컷 CL=0.951 CW+0.2033, 수컷 CL=0.9387 CW+2.0811)는 암수 모두 갑장에 비해 갑폭이 약간 끈 것으로 나타났으며, 갑폭과 체중의 관계 (암컷 BW=0.0123 CW$^{2.1693}$ , 숫컷 BW=0.0056 CW$^{2.3694}$)에서 체중의 변화는 동일 체급군에서 숫컷이 암컷보다 무겁게 나타났다. 또, 갑폭 64.9-96.0 mm에서 암컷의 평균 포란수(F=8.5285 CW$^{2.0498}$ )는 35,000~114,000개로 조사되었다. 갑폭에 대한 성숙개체 (암컷 외포란 및 난소 발달, 수컷 : vasa deferentia 관찰)의 비율은, 암컷의 경우 갑폭 54.2 mm 에서 약 50%, 갑폭 60.1 mm 이상에서는 100%였으며, 갑폭 42.3 mm 이하에서는 성숙개체가 관찰되지 않았다 수컷의 경우는 갑폭 58.8 mm, 72.0 mm 이상에서 각각 50%, 100%의 성숙개체 출현율을 나타냈으며, 갑폭 48.4 mm 이하에서는 성숙개체가 관찰되지 않았다.

• 한국응용곤충학회지
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• 제41권2호
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• pp.99-105
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• 2002

Tetrastichus sp.는 미국흰불나방의 번데기 기생벌로서, 1개의 숙주에 여러마리의 자손을 번식하는 집단 기생벌이며, 일년에 여러 세대 발생한다. 작잠, 신생아용 분유, 난황, 로얄젤리 등을 주요성분으로 기생벌의 인공먹이를 조성하였으며, polypropylene필름으로 번데기형태를 만들어 인공숙주로 사용하였다. 인공숙주에서 발육한 기생벌은 자연숙주에서 자란 기생벌보다는 크기가 작았으나, 계대 사육으로 번식 가능한 자손을 생산하였다. 인공숙주에서 발육한 in vitro 2세대의 생물학적 특성은 in vitro 1세대보다 훨씬 개선 었다. 평균 자손 수, 산란기간, 수명 등은 in vitro 에서 45.7,7.8, 13.8일 이었고 암컷 편중의 성비 76.9%를 나타내었다. 이러한 결과는 Tetrastichus sp.가 in vitro 대량사육에 적합한 기생벌임을 보여준다.

• International Journal of Industrial Entomology and Biomaterials
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• 제38권2호
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• pp.38-50
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• 2019

We investigated the developmental characteristics and life cycle of the lawn cutworm, Spodoptera depravata (Lepidoptera: Noctuidae), which is one of the most important pests causing economic damage in grass production. For larval culture, we provided the zoysiagrass at $25^{\circ}C$ and $60{\pm}5%$ humidity. The durations of the developmental stages were as follows: $4.11{\pm}0.19$ days for eggs, $25.17{\pm}3.02$ for larvae, $8.80{\pm}0.28$ for pupae, and $7.57{\pm}0.95$ for adults. We grew the larvae to the 7th instar stage, unlike previous studies, in which it was assumed that the 6th instar was the final age. There was a significant positive correlation between the body length and head capsule width of each instar larvae. In terms of morphology, the eggs changed from light green immediately following oviposition to black as they developed, and the grass-fed larvae changed from light yellow immediately after hatching to green as development continued. We observed a pattern of black spots at regular intervals on the dorsal sides of the abdomens of the final instar larvae. Furthermore, we detected two notable designs on the dorsal side of the front of the head. The pupal colors changed from light brown and green immediately after pupation, to dark brown as the pupal cuticle hardened. The wingspans of the adults were similar in both sexes. However, the forewings of the males had obvious outer lines and eyespots with dark gray-brown backgrounds, whereas the corresponding features on the female forewings were less obvious. The oviposition preperiod was 2.11 days, the oviposition period was 4.2 days, the average fecundity per female was approximately 341 eggs, and the hatching rate was approximately 76.1%.

• 한국의상디자인학회지
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• 제18권2호
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• pp.115-125
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• 2016

This study analyzes the characteristics of the motifs and colors in flower and bird paintings which contain and present Korea's unique aesthetics based on its richest data among all other types of Korean folk paintings. With a theoretical exploration of folk paintings and an analysis of the motifs and colors, textile design with an aim to present highly valued korean modern fashion design was developed. Two hundred and seventy flower and bird paintings were selected from relevant materials, resulting in an extraction of 5,068 colors. A palette of representative colors was made based on densely distributed hues and tones. The research can be summarized as follows: Flower and bird paintings contain flowers, birds, trees and animals and the motifs in the paintings stand for spirituality, philosophies from different times and other symbols of our nation. Each of the motifs in these paintings is a prayer for good luck, especially conjugal harmony and fecundity to bring about happiness and richness. Colors in flower and bird paintings are characteristic of the order: YR(25.5%)>R(19.2%)>Y(10.6%)>PB(9.2%)>G(7.9%), with low-chromatic YR and highly bright R taking up a larger percent. The order of tones is: d(13.5%)>dk (10.5%)>s(10.4%)>dkg(10.0%)>sf(9.1%)and the tone is dark in general. YR, taking up the largest percent, was dull, light, and soft. As for the achromatic colors, the order is: W(5.2%)>Gy(1.9%)>Bk(0.7%). Based on the above analyzed color data, those colors which were high in their hue and tone were extracted to present representative colors. In this way, representative colors like yellow, yellowish red, red, green, and purplish blue were extracted. This was the basis to present motifs and colors originating from subjects of folk paintings in various patterns using Illustrator CS6, to create modern fashion design.

• The Plant Pathology Journal
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• 제15권1호
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• pp.1-7
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• 1999

The production of soybean cyst nematode (SCN), Heterodera glycines, including female formation and fecundity was much higher in SCN race 14 (R14) than in race 3 (R3) in susceptible soybean cultivars Bragg (intolerant), Lee74 (moderately tolerant), and PI 97100 (highly tolerant). The nematode body was also significantly larger in R14 than in R3 at 20 days after inoculation, but the further nematode growth appeared to be slower in R14 than in R3, resulting in no significant difference between the two races at 30 days after inoculation. Within each race, no significant difference was observed in the growth and reproduction among the soybean cultivars tested. Syncytial areas near the nematode lip regions (infection sites) were measured for each soybean cultivar-SCN race combination. R14 induced significantly larger syncytia than R3. Bragg had relatively larger syncytia than Lee74 and PI 97100, but the difference among the soybean cultivars was minimal or not significantly different. Syncytium occupation in the stelar region differed only between PI 97100 and the other two cultivars, which may be somewhat, but not exactly, related to tolerance levels. Syncytial cytomplasm was degenerated more with R14 and in Bragg than with R3 and in Lee74 and PI 97100, respectively. In light microscopy, degenerated syncytia were characterized by depleted and loose cytoplasm with less plastids than normal-looking (intact) syncytia which had dense syncytial cytoplasm. Electron microscopy revealed that degenerated syncytia contained highly vacuolated cytoplasm with degenerated plastids. The above results suggest that structural characteristics of syncytia may match the nematode growth and reproduction.

• 한국패류학회지
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• 제31권2호
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• pp.113-121
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• 2015

Gametogenesis, mating behaviour and spawning of Octopus ocellatus were investigated by histological study. This species is dioecious, and showed a protandry phenomenon. Ooogenesis (in females) and spermatogenesis (in males) can be classified into 3 stages, respectively. O. ocellatus copulates in one of two ways: a male may leap upon a female, mounting her mantle, or a male may sit near the female and extend the hectocotylized third right arm toward her. Spawning occurred between April and June in females, and between March and May in males of O. ocellatus. The spawning period was once a year and the peak took place between May and June. A number of flatened follicle cells, which were attached to an oocyte, were involved in vitellogenesis in the cytoplasm of the vitellogenic oocyte (maturing oocyte), and formation of chorion membrane (secondary egg membrane) of the ovarian eggs. Fecundity per female closely related to GSI was 294-660 eggs (average, 429 eggs). The diameters of the ovarian eggs surrounded by chorion membrane were approximately in the range of 10.10-2.50 mm. Each ovarian egg laid by a female was connected to an egg string. Each egg string was 1-5.5 cm (average 3.6 cm). The total number of eggs laid by a female of this species ranged 218-314, the egg sizes were independent to the size of female adult. this species has a life mode showing some special reproductive characteristics of an annual semelparity as shown in Octopodidae species because we have never seen a female spawning a second time.

• 한국응용곤충학회지
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• 제48권1호
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• pp.11-19
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• 2009

충북 영동지역 과수원에 대발생하여 피해를 주고 있는 갈색여치의 발생소장, 영기별 발육특성, 온도별 발육기간, 수명 및 산란수를 조사하였다. 갈색여치는 2008년 3월 말부터 9월 초까지 발생하며 5월 중순이 발생최성기였다. 3월부터 부화약충이 나타나기 시작하여 과수를 가해하기 시작하는데 피해가 가장 많은 시기는 4-5령 약충인 5월 중순이며, 성충은 6월 상순부터 8월 중순까지 나타나며 발생최성기는 7월 중순이었다. 갈색여치의 전체밀도는 5월 중순이 가장 높았다. 1령에서 7령 약충기를 거쳐 성충이 되는 갈색여치는 4령부터 산란관이 바깥으로 노출되고 체중이 크게 증가하며, 6령부터 날개가 관찰되었다. 채집된 개체의 성비는 0.57로 암컷이 많았다. 영기별 약충 발육기간은 영기가 높아질수록 길어졌고, 20, 25, $30^{\circ}C$의 항온조건에서는 온도가 높아질수록 짧았다. 20, 25, $30^{\circ}C$순으로 온도가 높아질수록 산란전기간 역시 각각 5.0, 4.3일 그리고 3.4일로 짧아지고, 산란수는 각각 69.0, 87.1개 그리고 104.3개로 증가하였으나 성충수명은 $25^{\circ}C$조건에서 암수 각각 35.7, 32.9일로 가장 길고, $30^{\circ}C$에서 각각 30.1, 28.1일로 가장 짧았다. 암수 간 발육기간의 차이는 온도와 관계없이 암컷이 더 길었다. 산란은 토양 표면으로부터 $3{\sim}4\;cm$깊이에 가장 많이 분포하였으며, 산란초기에 알을 집중적으로 낳는 습성을 보였다.

• 한국응용곤충학회지
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• 제53권3호
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• pp.225-229
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• 2014

실험실 내에서 계절의 변화에 따른 애반딧불이(Luciola lateralis)의 계절적 특성을 조사하였다. 그 결과 산란 수는 겨울 $162.0{\pm}8.67$개, 봄 $226.9{\pm}15.84$개, 여름 $166.6{\pm}9.3$개였다. 산란 기간은 겨울 $6.9{\pm}0.59$일, 봄 $16.1{\pm}1.10$일, 여름 $8.2{\pm}0.61$일 이였다. 산란 간격은 겨울 $2.5{\pm}0.22$일, 봄 $3.9{\pm}0.25$일, 여름 $2.3{\pm}0.14$일 이였고, 산란 횟수는 겨울 $3.1{\pm}0.17$회, 봄 $4.1{\pm}0.29$회, 여름 $3.9{\pm}0.23$회 이였으며, 일회 산란 수 겨울 $52.2{\pm}4.56$개, 봄 $55.9{\pm}4.38$개, 여름 $42.2{\pm}3.76$개였다. 난기간은 겨울 $25.3{\pm}0.13$일, 봄 $29.6{\pm}0.18$일, 여름 $26.8{\pm}0.09$일 이였으며 부화하는데 걸리는 기간은 겨울 $3.0{\pm}0.28$일, 봄 $6.4{\pm}0.50$일, 여름 $4.6{\pm}0.32$일 이였다. 알의 부화율은 겨울 99.9%, 봄 99%, 여름 100%이였다. 계절별 성충수명은 겨울 암컷 $15.8{\pm}0.15$일, 수컷 $20.8{\pm}0.21$일 이였으며, 봄 암컷 $18.0{\pm}0.31$, 수컷 $21.4{\pm}0.37$일 이였고, 여름 암컷 $16.7{\pm}0.43$일, 수컷 $16.3{\pm}0.74$일 이였다. 또한 성충의 평균 수명을 보면 겨울 $17.9{\pm}0.14$일, 봄 $19.7{\pm}0.25$일, 여름 $16.5{\pm}0.43$일 이였다.

• 환경생물
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• 제40권3호
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• pp.281-289
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• 2022

본 연구에서는 온도에 따른 열대거세미나방의 산란 특성을 조사하였다. 18, 21, 24, 27, 30℃에서 열대거세미나방의 암컷 성충의 수명기간은 각각 19.2일, 22.4일, 20.4일, 19.0일 및 13.9일이었으며, 산란 전 기간은 각각 5.2일, 4.9일, 5.2일, 5.3일 및 3.5일이었고, 총산란 수는 각각 887.4개, 1,246.4개, 1,348.9개, 1,154.9개 및 1,034.2개였다. 온도별 열대거세미나방의 암컷 생존율은 18℃에서 13일 이후, 21℃에서 14일 이후, 27℃에서 15일 이후 및 24℃와 30℃에서는 9일 이후 급속하게 감소하였다. 산란 시작 후 3일째에 전체 산란의 50%가 이루어졌고, 18~24℃에서는 산란시작 후 7일째, 27~30℃에서는 5일째에 전체 산란의 90%가 완료되었다. 10엽기 이하의 옥수수 포장에서 열대거세미나방 성충은 하위엽에 41.4%, 중위엽에 46.8% 및 상위엽에 11.7%를 산란하였으며, 산란된 난괴의 66.7%가 잎 뒷면에 산란되었다. 열대거세미나방 성충을 5월 12일, 5월 17일, 5월 25일 및 5월 30일에 방사한 결과, 난괴당 알 수는 각각 89.9개, 88.5개, 126.6개 및 127.9개였다. 접종 후 세대성충의 산란은 6월 하순부터 관찰되었으며, 6월 하순에 산란된 난괴당 알 수는 155.8개, 7월 상순에 270.7개 및 7월 중순에 303.5개였다. 본 연구에서 보고한 열대거세미나방의 산란 특성은 성충 비래 시기에 따른 발생 예측 분석 및 방제 대책을 마련하는 데 활용될 수 있을 것이다.