가상 현실은 몰입감과 존재감을 극대화시킬 수 있다는 장점이 있어 비디오 게임, 교육, 치료 목적을 가진 다양한 콘텐츠에 널리 활용되고 있다. 또한 GearVR, DayDream, Occulus Quest 2 등의 HMD 등이 개발됨에 따라 가상 현실은 널리 보급되었다. 그러나 이러한 장비들을 사용하면 사용자가 실제 물리적인 세계를 볼 수 없다는 단점이 있어 실제 물체와 충돌하거나 넘어지는 위험한 상황에 빠질 수 있다. 만약 사용자가 시스 루 HMD를 사용하면 실제 물리적인 세계를 볼 수 있으므로 물체를 피할 수 있고 이러한 위험을 피할 수 있 는데 이러한 시스루 HMD는 광학 기반 방식이나 비디오 기반 방식으로 분류된다. 이러한 광학 기반 HMD는 렌즈를 통과하는 물리적 물체들을 볼 수 있지만 비용 문제가 있으며 비디오 기반 HMD는 비용과 카메라의 원본 이미지에 다양한 가상 효과를 추가할 수 있다는 장점이 있다. 본 논문은 이러한 장점들을 활용하여 저 렴한 비용으로 게임에 활용될 수 있도록 개발된 시스루 HMD를 설명하였으며 해당 HMD를 활용하는 게임 을 설명하였다. 본 논문을 통하여 개발된 비디오 시스루 HMD를 통해 더 많은 사용자가 저렴한 비용으로 혼합 현실 기반 게임을 즐길 수 있을 것으로 예상된다.

벼메뚜기는 분류학적으로 메뚜기목(Orthoptera), 메뚜기과(Acrididae)에 속하는 곤충으로 작물에 피해를 주는 해충으로 인식하고 있지만 예로부터 단백질 보충을 위하여 채집하여 튀기거나 볶음요리 로 이용해 왔다. 벼메뚜기는 갈색거저리, 쌍별귀뚜라미 등과 함께 식품공전에 등록되어 있으나 1년 1세대로 가을철에 채집하여 이용하는 실정으로 공급확대에 한계가 있다. 최근 우리나라에서 벼메뚜기를 사육하고자 하는 농가와 다양한 용도로 가공을 통해 이용하려는 수요가 점차 증가하고 있으나 연중사육기술이 개발되지 않아 대량사육하는 농가가 거의 없는 실정이다. 이에 벼메뚜기의 연중대량사육기술 뿐만 아니라 인공사료 및 자동화 사육시설 개발에 따른 생산비 절감 기술 개발이 필요한 실정이다. 벼메뚜기의 먹이로는 여름작물로 옥수수, 수단그래스, 겨울작물로 밀, 보리 등의 볏과작물이 있으며 많은 양의 생엽과 발육에 적합한 작물의 선발 및 볏과작물의 통곡실 가루를 이용한 인공사료의 개발로 먹이공급 부족 시 15~20일 급여 가능하며, 벼메뚜기 사육시설로 단독형, 연결형, 절충형 등의 사육시설을 개발하여 연결형 사육시설의 수확량과 생존율이 가장 높았으며, 예취 급이 노동력이 단독형의 16% 소요되었다.

Porcine spermatogonial stem cells (SSCs) prefer three-dimensional (3D) culture systems to 2D ones for the maintenance of self-renewal. Of the many 3D culture systems, agar-based hydrogels are candidates for supporting porcine SSC self-renewal, and there are various types of agar powder that can be used. In this study, we sought to identify an agar-based 3D hydrogel system that exhibited strong efficacy in the maintenance of porcine SSC self-renewal. First, 3D hydrogels with different mechanics were prepared with various concentrations of Bacto agar, lysogeny broth (LB) agar, and agarose powder, and the 3D hydrogel with the strongest alkaline phosphatase (AP) activity and greatest increase in colony size was identified for the different types of agar powder. Second, among the porcine SSCs cultured in the different 3D hydrogels, we analyzed the colony formation, morphology, and size; AP activity; and transcription and translation of porcine SSC-related genes, and these were compared to determine the optimal 3D hydrogel system for the maintenance of porcine SSC self-renewal. We found that 0.6% (w/v) Bacto agar-, 1% (w/v) LB agar-, and 0.2% (w/v) agarose-based 3D hydrogels showed the strongest maintenance of AP activity and the most pronounced increase in colony size in the culture of porcine SSCs. Moreover, among these hydrogels, the strongest transcription and translation of porcine SSC-related genes and largest colony size were detected in porcine SSCs cultured in the 0.2% (w/v) agarose-based 3D hydrogel, whereas there were no significant differences in colony formation and morphology. These results demonstrate that the 0.2% (w/v) agarose-based 3D hydrogel can be effectively used for the maintenance of porcine SSC self-renewal.

This studies was conducted to compare functional diversity of terrestrial arthropods in commercial apple orchards under conventional and organic practices. We collected terrestiral arthropods using pitfall traps in four conventional and seven organic apple orchards from April to October, 2012-2014. Sampled arthropods were identified at the species level and then classified three functional groups (detritivores, herbivores and beneficial arthropods included pollinators, parasitoids and predators). Biodiversity was analyzed with species richness, abundance and shannon index for each group and compared between conventional and organic orchards. In results, species richness of detritivores and benefical arthropods were higher in organic orchards than in conventional orchards (detritivores: t=-2.68, df=9, P=0.03; beneficial arthropods: t=-3.98, df=9, P=0.003). Organic orchards showed significant difference at abundance of beneficial arthropods (t=-3.33, df=9, P=0.008) and higher shannon index at detritivores (t=-2.36, df=9, P=0.04) than conventional orchards. However, all biodiversity indices of herbivores were not significantly different between conventional and organic orchards at 95% confidence level.

This studies was conducted to define community structure and diversity of epigeal spiders in apple orchards under different farming practices (organic and conventional). In 11 commercial apple orchards, epigeal spider community structure was investigated during 2012-2014 (3 orchards, 2012; 3 orchards, 2013, 5 orchards, 2014). Epigeal spiders were collected by pitfall traps from April to October, 2012 in Danyang-gun, Chungcheongbuk-do; 2013 in Muju-gun, Jeollabuk-do; 2014 in Cheongsong-gun and Uiseong-gun, Gyeongsangbuk-do, Korea. Sampled spiders were identified to the species level. Biodiversity was analyzed with species richness (total numbers of spider species), abundance (total numbers of individuals) and Shannon-Wiener diversity index (H΄) for each site and compared between organic and conventional orchards. In all regions, abundance of the spider communities were relatively higher in organic orchards than in conventional orchards. But, no significant difference in species richness and specie diversity (H΄) between organic and conventional orchards. Lycosidae was the most dominant family in all orchards regardless farming practices. However, Linyphiidae dominated in organic orchards only. The most dominant species were Pardosa laura (Lycosidae), Erigone koshiensis (Linyphiidae) in organic, Piratula procurvus (Lycosidae) in conventional orchards.

Despite many researches related with in-vitro culture of porcine spematogonial stem cells (SSCs), adherent culture system widely used has shown a limitation in the maintenance of porcine SSC self-renewal. Therefore, in order to overcome this obstacle, suspension culture, which is known to have numerous advantage over adherent culture, was applied to the culture of porcine SSCs. Porcine SSCs retrieved from neonatal testes were suspension-cultured for 5 days or 20 days, and characteristics of suspension-cultured porcine SSCs including proliferation, alkaline phosphatase (AP) activity, and self-renewal-specific gene expression were investigated and compared with those of adherent-cul-tured porcine SSCs. As the results, the suspension-cultured porcine SSCs showed entirely non-proliferative and significantly higher rate of AP-positive cells and expression of self-renewal-specific genes than the adherent-cultured porcine SSCs. In addition, long-term culture of porcine SSCs in suspension condition induced significant decrease in the yield of AP staining-positive cells on post-day 10 of culture. These results showed that suspension culture was inappropriate to culture porcine SSCs, because the culture of porcine SSCs in suspension condition didn’t stimulate proliferation and maintain AP activity of porcine SSCs, regardless of culture periods.

This study was conducted to investigate the community structure and species distribution of ground beetle assemblages in western part of Yeongwol-gun, Korea. Ground beetles were collected by pitfall traps from 9 study sites during July to October in 2013. A total of 30 species were identified from 4,439 collected ground beetles. Two dominant species, Synuchus nitidus (1,916 individuals) and Synuchus cycloderus (1,900 individuals) were occupied 85.8% of total. Interestingly, Pterostichus orientalis orientalis and Synuchus melantho were only collected in relative high altitude above 350 m, such as Beopheung-ri, Unhak-ri, and Yongseok-ri. Large-sized beetles, such as Damaster, Leptocarabus, and Carabus species, were generally more collected from Suju-myeon (Beopheung-ri and Unhak-ri) and Jucheon-myeon (Docheon-ri and Yongseok-ri) as well-conserved area, but not occurred in Yeongwol-eup and Hanbando-myeon, which forests may have lower habitat quality for these species. These differences also lead to increasing of dissimilarity among study sites, which were diverged into 3 groups at 53.0% of similarity. In particular, species composition of Samok-ri was significantly different at 8.2% of similarity because of difference in habitat characteristics as river side. This study has an important value to provide the fundamental information of inventory and monitoring in Yeongwol-gun. For detail mapping of species distribution in Yeongwol-gun, however, further studies are necessary, especially eastern parts of Yeongwol-gun.

Epigeic spiders (Araneae) were surveyed in apple orchards under different farming practices (organic and conventional) in Muju-gun, Jeollabuk-do, Korea. The study was conducted from April to October in 2013 with 2 weeks interval using pitfall traps. Collected spiders were identified as 20 species of 6 families from 819 individuals in organic orchardⅠ, 19 species of 10 families from 759 individuals in orchardⅡ and 16 species of 8 families from 209 individuals in conventional orchard for from 1,787 captured spiders. Biodiversity was analyzed with species richness, abundance and Shannon diversity index (H΄). Species richness was statistically higher in organic orchard than in conventional orchard. Organic orchardⅡ comprised the greatest abundance followed by organic orchard and conventional. But species diversity was the highest in organic orchardⅡ, intermediate in conventional orchard and the lowest in orchardⅠ. Lycosidae was the most dominant family in all orchards regardless farming practices. However, Linyphiidae dominated in organic orchards only. The most dominant species were Erigone koshiensis (Linyphiidae) in organicⅠ, Pardosa laura (Lycosidae) in organicⅡ and Arctosa pungcheunensis (Lycosidae) in conventional orchard.

Selecting surrogated species is the first step for environmental risk assessment of GM crop on non-target arthropods. To select surrogated species considering the domestic environment, we surveyed the arthropod fauna in five main localities (Changnyeong-gun in Gyeongsangnam-do, Goesan-gun in Chungcheongbuk-do, Gokseong-gun in Jeollanam-do, Hongcheon-gun in Gangwon-do and Hwaseong-si in Gyeonggi-do) in which maize was cultivated with large scale. Maize is one of the main imported GM crop in Korea. Arthropods were surveyed with yellow sticky traps and pitfall traps from May to August with a week interval considering the crop growing season in 2012 and 2013. A total of 135 species of 51 families in 13 orders were identified from the 17,470 arthropods. Six orders (Coleoptera, Araneae, Hemiptera, Diptera, Hymenoptera and Lepidoptera) were dominant in species richness and three orders (Collembola, Thysanoptera and Diptera) in abundance, representing 84% and 86% of the total, respectively. In the composition of fuctional guilds, herbivore group was the most dominant followed by predator group occupying 40% and 37% of the total abundance.

Matrix metalloproteinases (MMPs) have been known to affect to cell migration, proliferation, morphogenesis and apoptosis by degrading the extracellular matrix. In the previous studies, undifferentiated mouse embryonic stem cells (ESCs) were successfully proliferated inside the extracellular matrix (ECM) analog-conjugated three-dimensional (3D) poly ethylene glycol (PEG)-based hydrogel. However, there is no report about MMP secretion in ESCs, which makes it difficult to understand and explain how ESCs enlarge space and proliferate inside 3D PEG-based hydrogel constructed by crosslinkers containing MMP-specific cleavage peptide sequence. Therefore, we investigated what types of MMPs are released from undifferentiated ESCs and how extracellular signals derived from various niche conditions affect MMP expression of ESCs at the transcriptional level. Results showed that undifferentiated ESCs expressed specifically MMP2 and MMP3 mRNAs. Transcriptional up-regulation of MMP2 was caused by the 3D scaffold, and activation of integrin inside the 3D scaffold upregulated MMP2 mRNAs synergistically. Moreover, mouse embryonic fibroblasts (MEFs) on 2D matrix and 3D scaffold induced upregulation of MMP3 mRNAs, and activation of integrins through conjugation of extracellular matrix (ECM) analogs with 3D scaffold upregulated MMP3 mRNAs synergistically. These results suggest that successful proliferation of ESCs inside the 3D PEG-based hydrogel may be caused by increase of MMP2 and MMP3 expression resulting from 3D scaffold itself as well as activation of integrins inside the 3D PEG-based scaffold.

In apple orchards under different farming practices (organic and conventional), arthropod community structure was investigated. Arthropods were collected with pitfall traps, band traps, yellow sticky traps and pheromone traps from May to December, 2012 in Danyang-gun, Chungcheongbuk-do, Korea. Biodiversity was analyzed with species richness and Shannon diversity index (H΄). Sampled arthropods were identified 37 families in 14 orders from 21,618 individuals in organic orchard-1 and 33 families in 10 orders from 11,318 individuals in organic orchard-2 and 35 families in 13 orders from 27,711 individuals in conventional orchard. Species richness was relatively highest in organic orchard-1, intermediate in conventional orchard and lowest in organic orchard-2. In ecologically functional group, abundance of pests was higher in conventional orchard than in organic orchards due to the high occurrence of Phyllonorycte ringoniella (Gracillariidae) and Lyonetia prunifoliella (Lyonetiidae). Organic orchards showed higher abundance, species richness and species diversity of epigeic predators and those of parasitoids above ground than conventional orchard. Abundance of detritivores, mainly collembola, were higher in organic orchard than in conventional orchard.

This study aims to reveal how EA affects BAX and NF-kB involved in cell deaths from global ischemia, and to do this, observes the changes of BAX and NF-kB caused by EA application after transient global ischemia. The experimental method is to give rise to global ischemia and apply EA to 27 SD rats with the particulars of being six-week-old, male, around-300 gram-weighing, and adapted to laboratory environment for more than a week, and divide them into three groups, that is, GV20 EA group(n=9), L14 EA group(n=9), no-treatment GI group(n=9), and then observe their changes of BAX and NF-kB at the time lapse of 6 hours, 9 hours and 12 hours after ischemia, using western blotting. The numerical decrease of BAX expression at the time lapse of 9 hours after EA application, though not statistically significant, was observed in GV20 EA group and L14 EA group, and the NF-kB expression appeared statistically significant decrease in GV20 EA group and L14 EA group, but the expression was higher in the group with EA application. Therefore, EA application at the early phase of global ischemia is considered to affect BAX and NF-kB and play a positive role in decreasing apoptosis and cell deaths by inflammation.

수평 배향 액정 모드는 양의 유전율 이방성과 음의 유전융 이방성 액정을 사용한 프린지 필드 스위칭과 양의 유전율 이방성 액정을 사용한 인플래인 스위칭 모드가 대표적이다 . 이 대표적인 세 구동 방식의 화질 특성을 비교하기 위하여 각각의 최척화된 위상지연 값 조건하에서 밝기, 명암대비율과 색 특성을 조사하였다. 그 결과 양액정과 음액정을 사용한 프린지 필드 스위칭 모드가 밝기와 명암대비율 면에 있어서 인플래인 스위칭 모드보다 우수한 특성을 보인다. 또한 양액정을 사용한 프린지 필드 스위 칭 모드는 시야각 방향에서 적은 색 변이 특성을 보인다.

Presbyope has not clear vision with elderly changes. To introduce the essential preliminary examination for presbyope, we performed preliminary tests in 190 elderly patients with case history, slitlamp examination, pinhole test, Hirschberg test, pursuit, stereopsis, pupil reaction, Worth-4 dot test, Amsler grid test, dominant eye test. To perform an examination, the case history is clitical as it guides the whole examination. Chief complaints were epiphora, decreased visual acuity, floaters, hyperemia, eye pain, etc. From the information gained in the case history, we deduced a list of tentative diagnosis. Throughout the examination we decided whether additional tests. The 18.9% of patients didn't have improve visual acuity in pinhole test. Cause of reduced visual acuity in pinhole test was opaque of refractive media such as cataract or pterygium. In 44.7% of patients, stereoauity falls below 40s of arc. The 6.8% of patients have suppression of right or left eye. The 28.9% of patients have metamorphopsia or scotomas in Amsler chart test. Therefore, pinhole visual acuity helps to differentiate ocular pathology from lack of refractive media clarity. Amsler chart is also useful for monitoring age related maculopathy. We suggest that Jones dye test for tear drainage, pinhole test, Amsler grid test and Worth-4 dot test are essential for presbyope.