The present study examined the receptive and productive knowledge of collocations of second language (L2) and heritage speakers of Korean and also investigated the influence of phrasal frequency, exposure to Korean, and phonological short-term memory (PSTM). Seventeen L2 learners and 14 heritage speakers of Korean were tested on 30 Korean noun-verb collocations, which varied in phrasal frequency, using an acceptability judgment task and a collocation completion test. The results showed that both L2 and heritage speakers demonstrated considerable receptive knowledge of Korean collocations while productive knowledge was more limited for both groups. The mixed-effects modelling results of four independent variables of interest (i.e., phrasal frequency, exposure via media, academic use, and PSTM) showed that phrasal frequency was the only significant predictor of receptive knowledge of collocations for both L2 and heritage speakers; none of the four factors had a significant impact on productive knowledge of collocations for either group. These data are discussed in relation to previous studies on collocation development of L2 learners and heritage speakers.

In this study, using a continuous behavior measurement technique, the short-term behavioral responses and tolerance limits of red seabream Pagrus major fingerlings to sudden exposure to low salinity in a controlled environment were observed. The activity of the fingerlings suddenly exposed to 21.4, 17.3, and 9.8 psu increased temporarily at the initial exposure to show irregular swimming behavior, but then recovered a stable activity pattern through rapid salinity adaptation. However, the organisms suddenly exposed to 7.3 and 4.3 psu could not withstand the salinity stress, and their swimming behavior was severely disturbed and all individuals died within 48 hours. The findings suggest that red seabream underwent a temporary salinity stress process at the beginning of the exposure to concentrations of 10.0 psu or higher. At these concentrations, osmotic control was possible within at least 11 hours, so stable metabolic activity was also possible. However, organisms suddenly exposed to concentrations below 5.0 psu exceeded the tolerance to low salinity and the sublethal limit. In red seabream exposed to this concentration range, severe behavioral and metabolic disturbances were observed, and death was observed due to osmotic control failure. In conclusion, a salinity range of 5.0 to 10.0 psu can be predicted to correspond to a concentration range in which the osmotic control ability of the red seabream fingerlings is lost, and sub-lethal reactions occur.

외래해충은 자연생태계 교란과 농업환경의 파괴를 가져와 궁극적으로 우리 사회에 엄청난 사회적 비용과 경제적 손실을 유발한다. 이러한 외래해충의 국내 정착 시 대상 해충에 대한 효과적인 방제법과 천적 등의 부재로 박멸에 어려움이 있기에 검역의 역할은 매우 중요하다. 최근 붉은불개미와 금지급 과실파리류는 변화하는 기후와 국가 간교역량의 증가에 따라 최근 국내에서 발견되고 있다. 이를 위해 근연관계에 있는 일본열마디개미와 호박꽃과실파리를 대상으로 내한성을 조사하였다. 그 결과 두 종의 곤충은 저온처리(8℃에서 2시간) 후 체내빙결점의 저하가 나타났다. 또한 저온처리 후 –5℃에서 생존율은 호박꽃과실파리가 일본열마디개미 보다 높은 것으로 조사되었다.

Although piglets have been delivered by embryo transfer (ET) with in vitro produced (IVP) embryos and blastocysts, a success rate has still remained lower level. Unlike mouse, human, and bovine, it is difficult to a production of piglets by in vitro fertilization (IVF) because of an inappropriate in vitro culture (IVC) system in pig. Therefore, the present study was conducted to investigate whether minimized exposure time in IVC can improve the pregnancy and delivery rates of piglets. Immediately after IVM, the oocytes were denuded and co-incubated with freshly ejaculated boar semen for 3.5 to 4 hours at 38.5 ˚C under 5% CO2 in air. To avoid long-term exposure to in vitro state, we emitted IVC step after IVF. After that the presumptive zygotes were transferred into both oviducts of the surrogate on the same day or 1 day after the onset of estrus. Pregnancy was diagnosed on day 28 after ET and then was checked regularly every month by ultrasound examination. The 3 out of 4 surrogates were determined as pregnant (75%) and a total of 5 piglets (2 females and 3 males) were delivered at 118.3 ± 2.5 days of pregnancy period. In conclusion, a short-term exposure time may be an important factor in the production of IVP-derived piglets. It can be apply to the in vitro production system of transgenic pig by IVF, cloning, and pronuclear microinjection methods.