본 연구는 서울시의 강남구, 서초구, 송파구에 소재하고 있는 반일제 이상 교육기관(일명 영어유치원)에 다니는 유아 의 부모를 대상으로, 유아 사교육 수요동기 및 인식, 주거환경 및 사회경제적지위에 대한 인식을 알아보고, 이러한 요인 들이 사교육 참여 개수 및 비용에 미치는 영향을 알아보는 것을 목적으로 하였다. 이를 통해 학부모가 자녀 사교육과 관 련된 요인을 다면적으로 검토하고, 인식을 전환함으로써 과열된 유아 사교육이 완화되는 방안을 모색하였다. 이를 위해 학부모 396명을 대상으로 설문자료를 수집하였으며, IBM SPSS statistics 20 프로그램을 활용하여 자료를 분석하였다. 본 연구의 주요결과는 다음과 같다. 첫째, 학부모의 사교육 수요동기는 자녀의 인적자본을 축적하기 위해, 자녀를 잘 키우고 자, 자녀가 좀 더 나은 졸업장을 획득하게 하고자, 남들이 사교육을 받기 때문에, 자녀가 경쟁우위를 점하게 하고자 하는 순서로 분석되었다. 학부모의 사교육에 대한 인식은 기대감이 높은 반면, 부담감과 의존도는 상대적으로 낮고, 주거환경 보다 사회경제적지위에 대한 인식이 높은 것으로 나타났다. 둘째, 사교육 참여 개수는 자녀를 적게 낳는 만큼 잘 키우고 싶은 마음이 클수록, 부모의 학력과 소득이 높을수록, 자녀의 연령이 올라갈수록 많았다. 사교육비용은 자녀의 인적자본 을 축적하고 싶은 마음이 높을수록, 주거환경이 사교육에 노출되어 있고, 부모의 소득수준과 사교육경험이 있을수록, 자 녀의 연령이 높을수록, 부모가 해외거주 경험이 없을수록 높은 것으로 나타났다. 셋째, 사교육 수요동기 및 사교육 인식 과 사교육비용 간의 관계에서 주거환경 및 사회경제적지위 인식은 매개효과가 있는 것으로 나타났다.

This study investigated the effect of variation in the number of somaticcell- cloned embryos and their developmental stage at transfer on pregnancy, as well as the influence of the estrus status of recipient pigs on in vivo development of cloned porcine embryos after embryo transfer. For somatic cell nuclear transfer (SCNT), fibroblast cells were obtained from a male porcine fetus. Recipient oocytes were collected from prepubertal gilts at a local abattoir and then cultured. After SCNT, reconstructed embryos of different numbers and developmental stages were transferred into recipient pigs. The developmental stage of the cloned embryos and the number of transferred embryos per surrogate showed no significant differences in terms of the resulting cloning efficiency. However, the pregnancy rate improved gradually as the number of transferred cloned embryos was increased from 100- 150 or 151-200 to 201-300 per recipient. In pre-, peri-, and post-ovulation stages, pregnancy rates of 28.6%, 41.8%, and 67.6% and 16, 52, and 74 offspring were recorded, respectively. The number of cloned embryos and estrus status of the recipient pig at the time of transfer of the cloned embryo affect the efficiency of pig production; therefore, these variables should be particularly considered in order to increase the efficiency of somatic cell pig cloning.

Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the most important insect pests in the world. In the present study, the taxonomic status of B. tabaci and the number of species composing the B. tabaci complex were determined based on 1,059 COI sequences of B. tabaci and 509 COI sequences of 153 hemipteran species. The genetic divergence within B. tabaci was conspicuously higher (on average, 11.1%) than interspecific genetic divergence within the respective genera of the 153 species (on average, 6.5%). This result indicates that B. tabaci is composed of multiple species that may belong to different genera or subfamilies. A phylogenetic tree constructed based on 212 COI sequences without duplications revealed that the B. tabaci complex is composed of a total of 31 putative species, including a new species, JpL. However, genetic divergence within six species (Asia II 1, Asia II 7, Australia, Mediterranean, New World, and Sub Saharan Africa 1) was higher than 3.5%, which has been used as a threshold of species boundaries within the B. tabaci complex. These results suggest that it is necessary to increase the threshold for species boundaries up to 4% to distinguish the constituent species in the B. tabaci complex.

Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the most important insect pests in the world. In the present study, the taxonomic status of B. tabaci and the number of species consisting of the B. tabaci complex were determined based on 1059 COI sequences of B. tabaci and 509 COI sequences of 153 hemipteran species. The genetic divergence within B. tabaci was conspicuously higher (onaverage,11.1%) than interspecific genetic divergence within the respective genera of the 153 hemipteran species (on average, 6.5%). This result indicates that B. tabaci is composed of multiple biological species that may belong to different genera or subfamilies. The phylogenetic tree constructed based on 212 COI sequences without duplications revealed that the B. tabaci complex is composed of a total of 31 putative species, including a new species, JpL. However, genetic divergences within five species, Asia III, Asia II 7, Mediterranean, New world, and Sub Saharan Africa 1, were higher than 3.5%, which has previously been used as a threshold of genetic boundary in distinguishing species of the B. tabaci complex. These results suggest the necessity to redefine the threshold for species boundaries to best distinguish the constituent species in the B.tabaci complex.

Since the Bovine sequencing and HapMap projects, there have been millions of genetic variations particularly including single nucleotide polymorphisms (SNPs) available throughout the cattle genome. While cataloguing substantial amounts of SNPs, copy number variation (CNV) has recently become getting great attention as an another form of genetic variation which is extensively distributed across the cattle genome. As it has been well known that CNVs can account for substantial proportions of phenotypic variance in other species including human, CNVs are highly expected to explain genetic variations of diverse economically important traits in cattle. Currently, two main approaches such as hybridization-based microarray and massively parallel sequencing-based method have been successfully applied to detect CNVs throughout the cattle genome. Although there is obvious difference of capabilities to detect genome-wide CNVs at fine scales between different platforms applied, all currently completed investigations exhibited that CNVs are extensively spread throughout the cattle genome as observed in other species. Despite these successes, there are still severe lacks of researches to identify multiple levels of CNVs from diverse cattle or multiple individuals, suggesting that there are a number of CNVs remained undiscovered. Furthermore, there are almost few investigations available to elucidate how each CNV is associated with traits of interest in cattle, so such functional study should be followed along with saturating most of potential CNVs on cattle genome.

Spikelet number per unit area(SPN) is a major determinant of rice yield. Nitrogen nutrition status and biomass during reproductive stage determine the SPN. To formulate a model for estimating SPN, the 93 field experiment data collected from widely different regions with different japonica varieties in Korea and Japan were analyzed for the upper boundary lines of SPN responses to nitrogen nutrition index(NNI), shoot dry weight and shoot nitrogen content at panicle initiation and heading stage. The boundary lines of SPN showed asymptotic responses to all the above parameters(X) and were well fitted to the exponential function of f(X)=alphacdot1- etacdotexp(gamma;cdot;X) . Excluding the constant, from the boundary line equation, the values of the equation range from 0 to 1 and represent the indices of parameters expressing the degree of influence on SPN. In addition to those indices, the index of shoot dry weight increase during reproductive stage was calculated by directly dividing the shoot dry weight increase by the maximum value (800 extrmg/m-2 ) of dry weight increase as it showed linear relationship with SPN. Four indices selected by forward stepwise regression at the stay level of 0.05 were those for NNI (INNIP ) at panicle initiation, NNI(INNIh ) and shoot dry weight(IDWh ) at heading stage, and dry weight increase(IDW ) between those two stages. The following model was obtained: SPN=48683ㆍ IDWH 0.482 ㆍ INNIp 0.387 ㆍ INNIH 0.318 ㆍ IDW 0.35 ). This model accounted for about 89% of the variation of spikelet number. In conclusion this model could be used for estimating the spikelet number of japonica rice with some confidence in widely different regions and thus, integrated into a rice growth model as a component model for spikelet number estimation.n.n.