근래들어 미중 간의 기술패권 경쟁이 심화됨에 따라 미국은 중국의 첨 단반도체 기술의 발전을 저지하기 위한 다양한 경제적, 기술적 제재를 부과하고 있다. 최근에는 반도체산업의 글로벌 밸류체인(GVC, 가치사슬) 의 변동성 증대와 더불어, 미국 주도로 주요 반도체 생산국가들인 한국, 대만, 일본을 포함한 칩포(Chip-4) 동맹을 결성하기 위한 논의를 하고 있다. 물론 이러한 미중 간의 첨단기술 경쟁은 우리나라의 산업전반 특 히, 중국에 생산기지를 가지고 중국의 수요에 많이 의존하고 있는 우리 나라 반도체 산업에도 큰 영향을 미치지 않을 수 없다. 따라서 미중 간 반도체산업 분야의 기술경쟁 실태를 면밀하게 분석하고, 이를 토대로 우 리의 국익을 극대화할 수 있는 방안을 모색하는 것이 절실하다. 이러한 배경 하에서, 본 논문은 반도체산업을 중심으로, 현재 미중 간에 벌어지 고 있는 기술패권 경쟁에서 미국과 중국은 각기 어떠한 위치를 점하고 어떠한 전략을 구사하고 있는지를 분석하고, 이를 토대로 이러한 미중 간 기술경쟁이 우리나라 반도체산업에 미칠 영향을 점검하고 적절한 대 응방안을 모색하고자 하는 것이다.

In this work, the ablation behavior of monolith ZrB2-30 vol%SiC (Z30S) composites were studied under various oxy-acetylene flame angles. Typical oxidized microstructures (SiO2/SiC-depleted/ZrB2-SiC) were observed when the flame to Z30S was arranged vertically. However, formation of the outmost glassy SiO2 layer was hindered when the Z30S was tilted. The SiC-depleted region was fully exposed to air with reduced thickness when highly tilted. Traces of the ablated and island type SiO2 were observed at intermediate flame angles, which clearly verified the effect of flame angle on the ablation of the SiO2 layer. Furthermore, the observed maximum surface temperature of the Z30S gradually increased up to 2,200 °C proving that surface amorphous silica was continuously removed while monoclinic ZrO2 phase began to be exposed. A proposed ablation mechanism with respect to flame angles is discussed. This observation is expected to contribute to the design of complex-shaped UHTC applications for hypersonic vehicles and re-entry projectiles.

Demethoxycurcumin (DMC), which is a curcuminoid found in turmeric, has anti-proliferative effects on cancer cells. However, the effect of DMC on osteosarcoma has not been established. The aim of this study was to examine the effects of DMC on cell growth and apoptosis induction in MG-63 human osteosarcoma cells. This study was investigated using 3-[4, 5-dimethylthiazol-2-yl]-2, 5 diphenyl tetrazolium bromid assay, Live/Dead cell assay, 4’, 6-diamidino-2-phenylindole staining, and immunoblotting in MG-63 cells. DMC induced MG-63 cell death in a dosedependent manner, with an estimated IC50 value of 54.4 μM. DMC treatment resulted in nuclear condensation in MG-63 cells. DMC-induced apoptosis in MG-63 cells was mediated by the expression of Fas and activation of caspase-8, caspase-3, and poly (ADP-ribose) polymerase. Immunoblotting results showed that Bcl-2 and Bcl-xL were downregulated, while Bax and Bad were upregulated by DMC in MG-63 cells. These results indicated that DMC inhibits cell proliferation and induces apoptotic cell death in MG-63 human osteosarcoma cells via the death receptormediated extrinsic apoptotic pathway and mitochondria-mediated intrinsic apoptotic pathway.

Alpha-lipoic acid (ALA) is a naturally occurring antioxidant and has been previously used to treat diabetes and cardiovascular disease. However, the autophagy effects of ALA against oxidative stress-induced dopaminergic neuronal cell injury remain unclear. The aim of this study was to investigate the role of ALA in autophagy and apoptosis against oxidative stress in the SH-SY5Y human dopaminergic neuronal cell line. We examined SH-SY5Y phenotypes using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay (cell viability/proliferation), 4′,6-diamidino-2-phenylindole dihydrochloride nuclear staining, Live/Dead cell assay, cellular reactive oxygen species (ROS) assay, immunoblotting, and immunocytochemistry. Our data showed ALA attenuated hydrogen peroxide (H2O2)-induced ROS generation and cell death. ALA effectively suppressed Bax up-regulation and Bcl-2 and BclxL down-regulation. Furthermore, ALA increased the expression of the antioxidant enzyme, heme oxygenase-1. Moreover, the expression of Beclin-1 and LC-3 autophagy biomarkers was decreased by ALA in our cell model. Combined, these data suggest ALA protects human dopaminergic neuronal cells against H2O2-induced cell injury by inhibiting autophagy and apoptosis.

본 연구는 원통형 종이포트 토마토 육묘시 Diniconazole의 처리방법이 도장억제 및 근권발달에 미치는 영향을 검토하기 위하여 수행되었다. 그 결과, 엽면적, LAR, 초장, 충실도, 생체중, RGR 및 R/S 에서 시험구간 유의한 차이를 보였다. 동일한 농도를 처리했을 경우, 근권부와 지상부의 흡수도 차이로 인해 저면관수가 엽면살포에 비해 도장억제에 효과적이었다. 저면관수는 엽면시비의 10분의 1의 농도만으로도, 20~30%정도의 동일한 도장억제 효과를 얻을 수 있었다. 디니코나졸 처리에의한 근권부 반응이 흥미로웠는데, 저면관수시 총근장, 근권부피, 평균 근경 및 근단수가 증가하였다. 특히, 0.3mm 이하의 초미세근이 감소하고 0.3~0.6mm의 세근이 증가하였다. 따라서 원통형 종이포트 육묘시 저면관수를 하는 것이 기존 엽면시비에 비해 사용량이 적으면서도 도장억제 및 근권부 활착률을 높힐 수 있을 것으로 판단된다.

Acacetin, which is present in damiana (Turnera diffusa ) and black locust (Robinia pseudoacacia ), has several pharmacologic activities such as antioxidant, anti-inflammatory, and anti-proliferative effects on cancer cells. However, the effect of acacetin on head and neck cancers has not been clearly established. This study aimed to examine the effects of acacetin on cell growth and apoptosis induction in FaDu human pharyngeal carcinoma cells. These were investigated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay, Live/Dead cell assay, 4′,6-diamidino-2-phenylindole dihydrochloride staining, caspase-3 and caspase-7 activation assay, and immunoblotting in FaDu cells. Acacetin induced FaDu cell death in a dose-dependent manner, with an estimated IC50 value of 41.9 µM, without affecting the viability of L-929 mouse fibroblasts as normal cells. Acacetin treatment resulted in nuclear condensation in the FaDu cells. It promoted the proteolytic cleavage of procaspase-3, -7, -8, and -9 with increasing amounts of the cleaved caspase isoforms in FaDu cells. Acacetin-induced apoptosis in FaDu cells was mediated by the expression of Fas and activation of caspase-8, caspase-3, and poly (ADP-ribose) polymerase. Immunoblotting showed downregulation of the anti-apoptotic mitochondrial proteins Bcl-2 and Bcl-xL, but upregulation of the mitochondria-dependent pro-apoptotic proteins Bax and Badin FaDu cells after acacetin treatment. These findings indicate that acacetin inhibits cell proliferation and induces apoptotic cell death in FaDu human pharyngeal carcinoma cells via both the death receptor-mediated extrinsic apoptotic pathway and the mitochondria-mediated intrinsic apoptotic pathway.

Bilobalide isolated from the leaves of Ginkgo biloba has several pharmacological activities such as neuroprotective, anti-inflammatory, and anticonvulsant. However, the effect of bilobalide on cancer has not been clearly established. The main purpose of this study was to investigate the effect of bilobalide on cell growth and apoptosis induction in FaDu human pharyngeal squamous cell carcinoma. This was examined by 3-[4,5-dimethylthiazol-2-yl]-2,5- diphenyltetrazolium bromide assay, nuclear 4′,6-diamidino-2-phenylindole dihydrochloride staining, DNA fragmentation analysis, and immunoblotting. Bilobalide inhibited the growth of FaDu cells in dose- and time-dependent manners. Treatment with bilobalide resulted in nuclear condensation and DNA fragmentation in FaDu cells. Furthermore, it promoted the proteolytic cleavage of procaspase-3/-7/-8/-9 with increase in the amount of cleaved caspase-3/-7/-8/-9. Bilobalide-induced apoptosis in FaDu cells was mediated by the expression of Fas and the activation of caspase-8, caspase-3, and poly (ADP-ribose) polymerase. Immunoblotting revealed that the antiapoptotic mitochondrial protein Bcl-2 was downregulated, but the proapoptotic protein Bax was upregulated by bilobalide in FaDu cells. Bilobalide significantly increased Bax/Bcl-2 ratio. These results suggest that bilobalide inhibits cell proliferation and induces apoptosis in FaDu human pharyngeal squamous cell carcinoma via both the death receptor-mediated extrinsic apoptotic pathway and the mitochondrial-mediated intrinsic apoptotic pathway.

Visible and IR windows require a combination of high optical transparency and superior thermal and mechanical properties. Materials, fabrication and characterization of transparent ceramics for visible/IR windows are discussed in this review. The transparent polycrystalline Y2O3, Y2O3-MgO nanocomposites and MgAl2O4 spinel ceramics are fabricated by advanced ceramic processing and the use of special sintering technologies. Ceramic processing conditions for achieveing fully densified transparent ceramics are strongly dependent on the initial powder characteristics. In addition, appropriate use of sintering technologies, including vacuum sintering, hot-pressing and spark plasama sintering methods, results in outstanding thermal and mechanical properties as well as high optical transparency of the final products. Specifically, the elimination of light scattering factors, including residual pores, second phases and grain boundaries, is a key technique for improving the characteristics of the transparent ceramics. This paper discusses the current research issues related to synthesis methods and sintering processes for yttria-based transparent ceramics and MgAl2O4 spinel.

Core-shell structured nanoparticles are garnering attention because these nanoparticles are expected to have a wide range of applications. The objective of the present study is to improve the coating efficiency of gold shell formed on the surface of silica nanoparticles for SiO2@Au core-shell structure. For the efficient coating of gold shell, we attempt an in-situ synthesis method such that the nuclei of the gold nanoparticles are generated and grown on the surface of silica nanoparticles. This method can effectively form a gold shell as compared to the conventional method of attaching gold nanoparticles to silica particles. It is considered possible to form a dense gold shell because the problems caused by electrostatic repulsion between the gold nanoparticles in the conventional method are eliminated.

Resveratrol (3,4',5,-trihydroxystilbene), a phytoalexin present in grapes, exerts a variety of actions to reduce superoxides, prevents diabetes mellitus, and inhibits inflammation. Resveratrol acts as a chemo-preventive agent and induces apoptotic cell death in various cancer cells. However, the role of resveratrol in odontoblastic cell differentiation is unclear. In this study, the effect of resveratrol on regulating odontoblast differentiation was examined in MDPC-23 mouse odontoblastic cells derived from mouse dental papilla cells. Resveratrol significantly accelerated mineralization as compared with the control culture in differentiation of MDPC-23 cells. Resveratrol significantly increased expression of ALP mRNA as compared with the control in differentiation of MDPC-23 cells. Resveratrol significantly accelerated expression of ColⅠmRNA as compared with the control in differentiation of MDPC-23 cells. Resveratrol significantly increased expressions of DSPP and DMP-1 mRNAs as compared with the control in differentiation of MDPC-23 cells. Treatment of resveratrol did not significantly affect cell proliferation in MDPC-23 cells. Results suggest resveratrol facilitates odontoblast differentiation and mineralization in differentiation of MDPC-23 cells, and may have potential properties for development and clinical application of dentin regeneration materials.

Codium fragile (Suringar) Hariot is an edible green seaweed that belong to the Codiaceae family and has been used in Oriental medicine for the treatment of enterobiasis, dropsy, and dysuria. Methanol extract of codium fragile has anti-oxidant, anti-inflammatory and anti-cancer properties, although the anti-cancer effect on oral cancer has not yet been reported. In this study, we investigated the anti-cancer activity and the mechanism of cell death by methanol extracts of Codium fragile (MeCF) on human FaDu hypopharyngeal squamous carcinoma cells. Our data showed that MeCF inhibits cell viability in a dose-dependent manner, and markedly induced apoptosis, as determined by the MTT assay, Live/Dead assay, and DAPI stain. In addition, MeCF induced the proteolytic cleavage of procaspase -3, -7, -9 and poly(ADP-ribose) polymerase(PARP), and upregulated or downregulated the expression of mitochondrial-apoptosis factor, Bax(pro-apoptotic factor), and Bcl-2(anti-apoptotic factor), . Futhermore, MeCF induced a cell cycle arrest at the G1/S phase through suppressing the expression of the cell cycle cascade proteins, p21, CDK4, CyclinD1, and phospho-Rb. Taken together, these results indicated that MeCF inhibits cell growth, and this inhibition is mediated by caspase- and mitochondrial-dependent apoptotic pathways through cell cycle arrest at the G1/S phase in human FaDu hypopharyngeal squamous carcinoma cells. Therefore, methanol extracts of Codium fragile can be provided as a novel chemotherapeutic drug due to its growth inhibition effects and induction of apoptosis in human oral cancer cells.

Control mating is important aspect in bee breeding programs. The technique of artificial insemination is the possible one that can surely control mating of the selected drones with the virgin queen. This is the first time applied artificial insemination technique to control mating of A. cerana in Korea. Altogether 18 queens were artificially inseminated, and 2,000 drones of Korean A. cerana were used to evaluate amount of semen collection. Semen of A. cerana is much difficult to separate from mucus in comparing with A. mellifera. The average amount of semen can be collected from one A. cerana drone was 0.09 μl, whereas the A. mellifera was more than 6 times (0.58 μl semen per A mellifera drone). Obtaining 1 μl of semen have to collect from 11.94 drones that successful semen ejection and have to kill 17 A. cerana drones. Queens artificially inseminated with 4 μl of semen (once insemination) or 8 μl of semen (twice insemination, each with 4 μl of semen) started laying egg later than naturally mated queens 5.3 and 2.5 days, respectively. The onsets of oviposition of artificially inseminated queens were 12.5 to 15.3 days. Queens received twice inseminations started laying eggs 2.8 days earlier than those received only once insemination. Artificially inseminated queens produced exclusively brood and were similar as the naturally mated ones. The brood production of the queens received once insemination with 4 μl of semen was insignificantly different than those received twice inseminations or naturally mated ones, suggesting that one artificial insemination with 4 μl of semen is favorable.

Ficus carica L. (common fig), one of the first plants cultivated by humans, originated in the Mediterranean basin and currently grows worldwide, including southwest Asia and South Korea. It has been used as a traditional medicine for treatment of metabolic, cardiovascular, and respiratory diseases as well as hemorrhoids and skin infections. Its pharmacological properties have recently been studied in detail, but research on the anti-cancer effect of its latex has been only been studied on a limited basis on several cell lines, such prostate cancer, breast cancer, and leukemia. In this study, we investigated the anti-cancer activity of the latex of Ficus carica L.and its underlying mechanism in FaDu human hypopharynx squamous carcinoma cells. (See Ed. note above) We confirmed through SDS-PAGE analysis and gelatinolytic activity analysis that the latex of Ficus carica contains cysteine protease ficin. Our data showed that the latex inhibited cell growth in a dose-dependent manner. In addition, the latex treatment markedly induced apoptosis in FaDu cells as determined by FACS analysis, elevated expression level of cleaved caspase-9, -3 and PARP (poly (ADP-ribose) polymerase), and. increased the expression of Bax (pro-apoptotic factor) while decreasing the expression of Bcl-2 (anti-apoptotic factor). Taken together, these results suggested that latex containing the ficin inhibited cell growth and induced apoptosis by caspase and the Bcl-2 family signaling pathway in FaDu human hypopharynx squamous carcinoma cells. These findings point to the potential of latex of Ficus carica to provide a novel chemotherapeutic drug due to its growth inhibition effects and induction of apoptosis in human oral cancer cells.

Anthriscus sylvestris (L.) Hoffm. is a perennial herb found widely distributed in various regions of Korea, Europe, and New Zealand. The root of A. sylvestris have been extensively used in the treatment for antitussive, antipyretic, cough remedy in Oriental medicine, but the physiologically active function of the leaf of A. sylvestris is as yet unknown. In this study, we investigated the anti-cancer activity and the mechanism of cell death of water extracts of leaf of Anthriscus sylvestris (WELAS), on human FaDu hypopharyngeal squamous carcinoma cells. Our data showed that WELAS treatment inhibited cell viability in a concentration- and time-dependent manner. In addition, the treatment of WELAS markedly induced apoptosis in FaDu cells, as determined by the viability assay, DAPI stain and FACS analysis. WELAS also increased the proteolytic cleavage of procaspase-3, -9 and PARP (poly(ADP-ribose) polymerase). In addition, exposure to WELAS decreased the expression of Bcl-2 (an anti-apoptotic factor), but increased the expression of Bax (a pro-apoptotic factor), suggesting that mitochondria-dependent apoptotic pathways are mediated in WELAS-induced apoptosis. Taken together, these results indicate that water extracts of leaf of A. sylvestris inhibits cell growth and induces apoptosis via the mitochondrial-dependent apoptotic pathway in FaDu human hypopharyngeal squamous carcinoma cells. Therefore, we propose that the water extracts of leaf of A. sylvestris is a novel chemotherapeutic drug, having growth inhibitory properties and induction of apoptosis in human oral cancer cells.

Metformin (1,1-dimethylbiguanide hydrochloride), derived from French lilac (Galega officinalis), is a first-line anti-diabetic drug prescribed for patients with type 2 diabetes. However, the role of metformin in odontoblastic cell differentiation is still unclear. This study therefore undertook to examine the effect of metformin on regulating odontoblast differentiation in MDPC-23 mouse odontoblastic cells derived from mouse dental papilla cells. As compared to controls, metformin significantly accelerated the mineralization, significantly increased and accelerated the expressions of ALP and Col I mRNAs, and significantly increased the accelerated expressions of DSPP and DMP-1 mRNAs, during differentiation of MDPC-23 cells. There was no alteration in cell proliferation of MDPC-23 cells, on exposure to metformin. These results suggest that the effect of metformin on MDPC-23 mouse odontoblastic cells derived from mouse dental papilla cells, facilitates the odontoblast differentiation and mineralization, without altering the cell proliferation.

Due to their environmental and economical consequences, invasive species have become a major concern worldwide. Among them, the yellow-legged hornet, Vespa velutina, is a keen hunter of domestic honeybees. They use olfactory cues from the prey to assess food information. In this study, we investigated the attraction behavior of V. velutina to honeybee pheromone under outdoor conditions. Nine honeybee pheromones were tested and compared in order to find the best attractant. When testing specific compounds, the honeybee queen pheromone, homovanillyl alcohol, proved highly attractive.

Dermanyssus gallinae is parasitic to chicken, and they cause many damages such as disturbing sleep reducing for body weight and egg production by blood-sucking. To develop acaricide against D. gallinae, The acaricidal activity of 40 species plant extract were examined. Cnidium officinale extracted by Me-OH showed 82.0% acaricidal activity after treated 48 hrs at 4,000 ppm. The hexane fraction showed 92.4% mortality against D. gallinae at 48 hrs at 2,000 ppm. Purification of the biologically active constituents from the hexane extraction with acaricidal activity was done using silica gel open column chromatography and HPLC. H1122 fraction gave 80.9% mortality to D. gallinae at 400 ppm after treated 48 hrs. H1122 fraction was analyzed by GC-MS and NMR.