As a part of enhancing the performance of wood-plastic composites (WPC), polypropylene (PP)/ nanoclay (NC)/ wood flour (WF) nanocomposites were prepared using melt blending and injection molding process to evaluate their thermal stability. Thermogravimetric analysis (TGA) was employed to investigate thermal degradation kinetics of the nanocomposites both dynamic and isothermal conditions. Dynamic scans of the TGA showed an increased thermal stability of the nanocomposites at moderate wood flour concentrations (up to 20 phr, percentage based on hundred percent resin) while it decreased with the addition of 30 phr wood flour. The activation energy (Ea) of thermal degradation of nanocomposites increased when nanoclay was added and the concentration of wood flour increased. Different equations were used to evaluate isothermal degradation kinetics using the rate of thermal degradation of the composites, expressed as weight loss (%) from their isothermal TGA curves. Degradation occurred at faster rate in the initial stages of about 60 min., and then proceeded in a gradual manner. However, nanocomposites with wood flour of 30 phr heated at 300℃ showed a drastic difference in their degradation behavior, and reached almost a complete decomposition after 40 min. of the isothermal heating. The degree of decomposition was greater at higher temperatures, and the residual weight of isothermal degradation of nanocomposites greatly varied from about 10 to 90%, depending on isothermal temperatures. The isothermal degradation of nanocomposites also increased their thermal stability with the addition of 1 phr nanoclay and of wood flour up to 20 phr. But, the degradation of PP100/NC1/MAPP3/WF30 nanocomposites with 30 phr wood flour occurs at a faster rate compared to those of the others, indicating a decrease in their thermal stability.

The properties and electrochemical characteristics of anode material using pitch-coated graphite residue compounds by heat-treatment at 600℃ for 1 hour were investigated. The distance of layers of pitch-coated graphite residual compounds was 3.3539 a, which was as same as that of graphite. Its electrochemical and charge discharge characteristics were tested according to different four types of carbon material, natural graphite, pitch-coated graphite, amorphous graphite and pitch-coated graphite residual compounds, respectively. So it was shown the best charge-discharge characteristics in all of the samples. For the electrochemical and charge-discharge characteristics, although pitch-coated graphite residual compounds had different carbon contents 70% and 80%, these two samples were shown good electrochemical and charge-discharge characteristics.

가압경수로형 원자력발전소의 운영과정에서 발생된 폐수지내 및 의 분포특성을 조사하였다. 표준용액을 사용한 의 회수율 측정결과, 사용한 산의 종류에 관계없이, 3 N-HCl , 주입한 농도 범위에서 의 회수율을 나타내었다. 같은 장치를 사용하여 HTO 표준용액 증류에 의한 의 회수율은 주입한 농도 범위에서 이었다. 습식산화-산용출법에 의한 폐수지의 및 동시분리시, 를 사용했을 때 다른 감마핵종에 의한 방해가 없었으며, 포집액이 섬광제와 잘 혼합되었다. 그러나 3 N-HCl을 사용했을 때 포집용액에서 및 등의 감마핵종이 검출되었다. 또한 Sample Oxidizer에 의한 포집용액에서도 및 등이 검출되었으며, 포집용액에서는 이 검출되었다. 폐수지의 총 함량중 약 70% 이상이 무기 탄소로 확인되었다. 30개 폐수지 시료중 8개 고방사능 폐수지의 및 의 평균농도는 각각 이었으며 22개 저방사능폐수지에서는 각각 이 검출되었다. 고방사능 폐수지의 평균 비는 28로 저방사능 폐수지의 0.70에 비해 높게 나타났으며, 및 의 농도는 서로 비례하는 경향을 보였다.

[ TiO2 ]ACF composites were prepared by the electrochemical method with Titanium (IV) n-butoxide (TNB) electrolyte under different electrochemical operation time. The BET surface area for TiO2/ACF composites decrease with the increase of electrochemical operation time. There is a single crystal structure which is anatase in all of the samples from the data of XRD. The SEM micrphotographs of TiO2/ACF composites show that the TiO2 particles were well mixed with the ACF. There are O and P with strong C and Ti peaks in all samples from EDX results, and it also shows that a decrease of the C content with a increasing of Ti content with increasing of the electrochemical operation time in the over all composites. DSC cures show that the exothermic peak of all composites at 560℃ represents the transformation heat of amorphous parts to anatase phase and the discontinuous grain growth of the transformed anatase particles. Finally, the excellent photoactivity of TiO2/ACF composites (especially, ACFT10) could be attributed that the decrease of concentration of MB can be concluded to be much faster for the adsorption by ACF than for photocatalytic decomposition by TiO2.

Somatic cells nuclear transfer (SCNT) is a useful tool in studies of developmental biology and animal cloning. However, SCNT experiments only are allowed to skilled technical experts. In this experiment, laser-assisted zona pellucida piercing tool (LASER) was applied in murine SCNT. LASER minimized the use of piezo-driven micromanipulator (PIEZO), reducing chances of problems caused by PIEZO pulses. LASER reduced time that took to pierce zona pellucida in removal of nucleus from oocyte and somatic cell injection, which might have taken longer time with PIEZO. Time and difficulties that took researcher of equivalent skilled for their experiments were decreased with LASER, and this might affect the improvement of embryonic development. (LASER, 6.2% versus PIEZO, 2.9%; P<0.05). Thus, these data support that the use of LASER can be used for zona pellucida piercing in murine SCNT program as an alternative to PIEZO.

This paper describes the state-of-the art research activities on seismic isolation systems for improving the seismic capacities of the bridges in Korea. Though Korea is located in a region of low-to-moderate seismicity, the construction of seismic isolation systems has increased rapidly. The application of seismic isolation system has become popular worldwide because of its stable behavior and economical construction especially for bridge structures. Since optimal reliability level of isolated bridges can be determined as the one that provides the highest net life-cycle benefit to society, or the minimum Life-Cycle Cost (LCC), an optimal design procedure based on minimum LCC concept is more expedient for the design of seismically isolated bridges in areas of low-to-moderate seismicty. To verify the adequacy of the new design concept based on the LCC minimization, experimental studies on seismically isolated bridge are introduced as well, which include pseudo-dynamic test of scaled pier and dynamic field test of full-scale. With the application of seismic isolation systems, many kinds of dampers to improve the seismic capacity of structure are also applied not only to new bridges but also to existing bridges.

This paper verifies the difference of the seismic behavior and seismic damage of the neighboring two reinforced concrete piers damaged by the 1995 Hyogoken Nanbu earthquake. The two piers were almost the same size, carrying slightly different dead load, and were provided with the same reinforcement arrangement except the amount of longitudinal reinforcement at the bottom portion of the piers. The pier with more reinforcement was completely collapsed due to this near field earthquake by shear failure at the longitudinal reinforcement cut-off while the other was only damaged at the bottom by flexure even though the longitudinal reinforcement cut-off was also existed at the mid height of the pier. According to the results of the pseudo dynamic test, the seismic damage was recognized to be greatly dependent on the ground motion characteristics even though the employed ground motions had the same peak acceleration. The severe damage was observed when the test employed the seismic wave that had strong influence to the longer period range compared to the initial natural period of the pier. On the other hand, based on the similar model experiment, the defect of gas-pressure welded splice of longitudinal reinforcement was revealed to save the piers against collapse due to the so-called fail-safe mechanism contrary to the intuitive opinion of some researchers. It was concluded that the primary cause of the collapse of the pier was the extremely strong intensity and peculiar characteristics of the earthquake motion according to both the site-specific and the structure-specific effects.

빛은 인간과 동물에서 일주 리듬과 신경내분비 활동을 조절하는 자극이다. 망막-시상하부 경로는 주/야 주기와 신경내분비 활동에 관여한다. 특히 멜라토닌 분비는 빛에 의해 영향을 받으며, 다양한 측면의 건강 문제와 관련이 있다는 것이 알려져 왔다. 본 논문은 생물학적 리듬과 신경내분비 활동에 있어서 빛이 수행하는 역할과, 빛과 건강 문제와의 관련성, 망막-시상하부 경로의 특성을 소개하고자 한다.

This study was conducted to evaluate the effect of cytochalasin B (CB) treatment in the activation medium on the development of somatic cell nuclear transfer (SCNT) rat embryos. Fetal fibroblast cells were isolated from a Day 14.5 fetus, and the oocytes for recipient cytoplasm were recovered from 4-week old Sprague Dawley rats. After enucleation and nuclear injection, the reconstructed oocytes were immediately exposed to activation medium consisting of 10 mM SrCl2 with or without CB for 4 hr, and formation of pseudo-pronucleus (PPN) was checked at 18 hr after activation. Then, they were transferred into day 1 pseudopregnant recipients (Hooded Wistar) or cultured for 5 days to check their developmental competence in vivo or in vitro. The number of PPN was not affected by CB treatment during the activation. However, CB treatment supported pre-implantation development of rat SCNT embryos. Embryos generated by the procedures of SCNT were also capable of implanting, with 1 implantation scar found from a recipient following the transfer of 87 SCNT embryos to four foster mothers. The result of the present study shows that rat SCNT embryo can develop to post-implantation stage following treatment with CB.

In this work, activated carbon (AC) after HNO3 modification was used as the support during the production of supported TiO2 to increase the high deposition efficiency and the photocatalytic activity. The results of N2 adsorption showed that the BET surface area of samples decreased with an increasing of the concentration of HNO3 due to the penetration of TiO2. From XRD data, a single crystal structure of anatase peak was observed in diffraction patterns for the AC coated with titanium complexes. From the SEM results, almost all particles were aggregated with each other at the carbon surface and AC was covered with TiO2 particles in all of the samples. The EDX spectra show the presence of C, O, Ti and other elements. It was also observed a decreasing of amount of C content with increasing Ti and O content from the EDX. The results of FT-IR revealed that the modified AC contained more surface oxygen bearing groups than that of the original AC. The effect of surface acidity and basity calculated from Boehm titration method was also evaluated from correlations as a function of NaOH, NaHCO3, and Na2CO3 uptake. The surface modification of AC by HNO3 leads to an increase in the catalytic efficiency of AC/TiO2 catalysts, and the catalytic efficiency increases with increasing of HNO3 concentration.

In vitro development of porcine embryo is affected by culture condition. One possible factor is osmolarity of culture medium. This study examined whether high osmolarity of culture medium at the early culture stage improves development of preimplantation porcine in vitro fertilization (IVF) and nuclear transfer (NT) embryos. NT and IVF embryos were divided into three groups and the basic medium was PZM-3 (250～270 mOsmol, control group). The control group of embryos was cultured in PZM-3 for whole culture period. Other two groups of embryos were cultured in a modified PZM-3 with 0.05 M sorbitol or 0.05 M sucrose (300～320 mOsmol, sorbitol or sucrose group) for the first 2 days, and then cultured in PZM-3 for further culture. NT embryos cultured in sucrose group showed a significantly higher developmental rate to the blastocyst stage with a decreased apoptosis rate compared to the sorbitol (p<0.05). For IVF, sucrose group showed a significantly increased the blastocyst formation rate with a decreased apoptosis rate compared to the control (p<0.05). This study represents that the high osmolarity in the early embryo culture stage can enhance the in vitro development of porcine NT and IVF embryos to the blastocyst stage with reduced apoptosis of cells.

Periodontitis is a chronic infectious disease that leads to periodontal destruction, and is one of the major causes of tooth loss in humans. The osteoclast differentiation factor (ODF), which is also known as the receptor activator of the NF-kB ligand (RANKL), is a surface-associated ligand on bone marrow stromal cells and osteoblasts. RANKL activates its cognate receptor, RANK, on osteoclast progenitor cells, which leads to the differentiation of mononucleated precursor cells. Osteoprotegerin (OPG) is a decoy receptor that is released from stromal cells and osteoblasts to inhibit the interaction between RANKL and RANK. Although the precise mechanism of bone loss in periodontitis is unknown, the differentiation and activation of osteoclasts by OPG-ODF-RANK signaling might play the role in periodontal bone destruction. The relationship between the concentration of sex hormones and the expression of ODF and OPG was examined by treating human gingival fibroblasts and periodontal ligament cells with the normal serum concentration of estrogen or progesterone during menstruation or at menopause. The ODF/OPG relative ratio was elevated at the concentration observed during ovulation in human gingival fibroblasts and at the concentration observed between ovulation and menstruation in periodontal ligament cells treated with estrogen. However, the ratio was <1 at all concentrations in both cells treated with progesterone. In the case of menopause simulated by estrogen depletion, the ratio was <1 in human gingival fibroblasts but >1 in periodontal ligament cells.

This project aims at suggesting the direction of school leadership in relation to education management through conducting a case study of Indonesia. For a long time, Indonesia has focused on a centralistic education management, Thus, every school principal had limited authority in policy making and in running the school management functions being constrained by these particular guides and other government rules. In 2000, in implementing the Law number 2211999 on Regional Autonomy, Indonesia was able to advance the decentralization of the education management system. Every autonomous region (in this case district or kota/mayoral) has greater authority to run its education management functions in its own region, especially those at the primary and secondary levels of education. This has affected the need to reform education and school management in regard to making it more effective and more efficient by applying the principles of accountability and transparency. In the future, school management will apply a school-base management approach. Its application needs to be supported by the application of ICT

'Directions of APEC Future Policy for JCT in Education' aims at identifYing trends of APEC policy for ICT in education, its related issues, and makes recommendations for future policies. The results of this research are expected to provide a benchmark for educational ICT policy making in APEC economies with reference to policy trends produced by this project. They also provide insights and hindsight on ICT educational policymaking to all parties concerned. APEC economies should find the results beneficial in terms of new policymaking and enhancement of present policies. The recommended policy areas should be translated to generate businesses suited for industries related to ICT and education. As to the methodology, from eleven APEC economies the sample is reduced to eight due to complications in communications and documentation. Information needed was obtained through the internet. The project leader organized and distributed the collected data online to other members of the project (PR. China & Thailand) for analysis. The technique of content analysis was applied and trends on APEC educational JCT policy were identified. Findings from the data analysis were tabulated and are attached as appendices in the APEC white paper.