Nanosized zeolites were prepared in an autoclave using tetraethoxysilane (TEOS), tetrapropylammonium hydroxide (TPAOH), and H2O, at various hydrothermal synthesis temperatures. Using transmission electron microscopy and particle size analysis, the nanopowder particulate sizes were revealed to be 10-300 nm. X-ray diffraction analysis confirmed that the synthesized nanopowder was silicalite-1 zeolite. Using atomic layer deposition, the fabricated zeolite nanopowder particles were coated with nanoscale TiO2 films. The TiO2 films were prepared at 300 oC by using Ti[N(CH3)2]4 and H2O as precursor and reactant gas, respectively. In the TEM analysis, the growth rate was ~0.7 Å/cycle. Zeta potential and sedimentation test results indicated that, owing to the electrostatic repulsion between TiO2-coated layers on the surface of the zeolite nanoparticles, the dispersibility of the coated nanoparticles was higher than that of the uncoated nanoparticles. In addition, the effect of the coated nanoparticles on the photodecomposition was studied for the irradiation time of 240 min; the concentration of methylene blue was found to decrease to 48%.
The present study is designed to explore an anti-tumor activity on crude extracts of Oplopanax elatus. Water extractions of Oplopanax elatus were performed at 100℃(OeE-100). OeE-100 doses up to 62.5 ㎍/㎖ had no cytotoxicity on the tumor cell lines in vitro. In experimental lung metastasis of colon26-M3.1 carcinoma or B16-BL6 melanoma, the prophylactic intravenous (4~100 ㎍/mouse) or oral (2 ㎎/mouse) administration of OeE-100 significantly inhibited tumor metastasis as compared with tumor controls. Peritoneal macrophages stimulated with OeE-100 produced various cytokines such as TNF-α, IL-6 and IL-12. In an analysis of NK-cell activities, i.v. administration of OeE-100 (10~100 ㎍/mouse) significantly augmented the cytotoxicity to YAC-1 tumor cells. Vaccination of mice with boiling-treated tumor cells (BT-vaccine) in combination with OeE-100 (100 ㎍/mouse) showed higher inhibitions in tumor metastasis when compared with the mice of BT-vaccine treatment. In addition, the splenocytes from OeE-100 admixed BT-vaccine immunized mice secreted a higher concentration of Th1 type cytokine such as IFN-γ. These results suggested that the OeE-100 stimulated immune system and was a good candidate adjuvant of anti-tumor immune responses.
The purpose of this study is to identify which width of the base of support(BOS) is safer and more effective in lifting by comparing muscle activations and body sways when lifting objects under the width variation of the BOS. A total of fifteen healthy adults participated in this study. For the width variation of the BOS, the participants changed the width between their feet into three different types(10cm, 32cm, 45cm) and lifted a 10kg four times in each type after going up on a force plate. In order to measure body sways according to the width variation of the BOS, a motion analysis system was used. In addition, in order to measure the muscle activations of lower extremities, including the erector spinae, gluteus maximus, rectus femoris, and tibialis anterior, an electromyogram(EMG) analysis was employed. In addition, the Borg's scale was drawn by quantifying the subjective discomfort levels felt from each width of the BOS. In conclusion, no statistically significant differences according to the width variation of the BOS were observed(p=.295, .308)(p>.05). However, a statistically significant difference was exhibited between the Borg's scale, which indicates the discomfort levels from lifting performances, and the width variation of the BOS (p=.000*).
에멀션 기반의 계면활성제를 이용한 주형합성법을 이용하여 산촉매로서 염산과 실리카의 전구체인 테 트라에톡시실란을 사용함으로써 메조다공성 실리카 마이크로스피어를 합성하였다. 테트라에톡시실란의 농도 증가에 의해 구형의 입자 형태가 파괴되었고, 기공구조도 크게 변하였다. 산촉매 농도 증가에 의한 구형의 입자형태 파괴 현상은 적었지만 상대적으로 작은 크기의 구형의 마이크로입자가 더 많이 생성되 었다. 하지만, 산성조건에서 입자들 간의 강한 응집현상이 나타남에 따라 낱개의 분리되어 있는 단일입자 를 얻기 위해서는 초음파 등의 후처리 과정이 필요하였다.