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Modulation Linearity Characterization of Si Ring Modulators
Modulation linearity of Si ring modulators (RMs) is investigated through the numerical simulation based on the coupled-mode theory and experimental verification. Numerical values of the key parameters needed for the simulation are experimentally extracted. Simulation and measurement results agree well. With these, the influence of input optical wavelength and power on the Si RM linearity are characterized
Insect Fauna of Mt. Jang-san, Yeongwol-gun, Gangwon-do, Korea
AbstractAn entomofauna study of Jangsan Mountain (1,408.8 m) in Yeongwol-gun, Gangwon-do was carried out from April to September, 2010. The distribution of 384 species, 91 families and 12 orders was confirmed from the study area
Novel Packet Switching for Green IP Networks
A green technology for reducing energy consumption has become a critical factor in ICT industries. However, for the telecommunications sector in particular, most network elements are not usually optimized for power efficiency. Here, we propose a novel energy-efficient packet switching method for use in an IP network for reducing unnecessary energy consumption. As a green networking approach, we first classify the network nodes into either header or member nodes. The member nodes then put the routing-related module at layer 3 to sleep under the assumption that the layer in the OSI model can operate independently. The entire set of network nodes is then partitioned into clusters consisting of one header node and multiple member nodes. Then, only the header node in a cluster conducts IP routing and its member nodes conduct packet switching using a specially designed identifier, a tag. To investigate the impact of the proposed scheme, we conducted a number of simulations using wellknown real network topologies and achieved a more energy-efficient performance than that achieved in previous studies.Peer reviewe
Immune-enhancing screening of fourteen plants on murine macrophage RAW 264.7 cells
Purpose: To investigate the potential immune-enhancing effects of fourteen natural plant extracts on mouse macrophage RAW 264.7 cells.Methods: Fourteen plant extracts from 7 different plants were tested on RAW 264.7 cells to determine their immunostimulant activities. Methylthiazolydiphenyltetrazolium bromide (MTT) and Griess assays were performed to evaluate cell viability and nitric oxide (NO) production, respectively. Then, immune related proteins were measured by western blot analysis, while cytokines and phagocytic activity were determined by enzyme-linked immunosorbent assay (ELISA) method.Results: Among the 14 plant extracts, the hot water extract of Agastache rugose was selected based on the screening results on NO production. The hot water extract of A. rugose significantly increased NO production in a concentration-dependent manner without any cytotoxicity. In addition, the expression levels of proteins (iNOS and COX-2) and cytokines (TNF-α, IL-1β, IL-6 and IL-12) closely related to immune reaction were also significantly upregulated. Furthermore, phagocytic activity of RAW 264.7 cells significantly increased following treatment with A. rugosa.Conclusion: The hot water extract of A. rugosa exhibits significant immune-stimulant activity. Therefore, A. rugosa can be used as a natural resource for immune enhancement or dietary supplement.Keywords: Immune enhancing activity, Macrophage polarization, Natural plant extracts, Agastache rugosa, RAW 264.
Insect Fauna of Island Gangwha-do with its nearby Islands, Incheon Metropolitan city, Korea
AbstractThis study was conducted to clarify the current status of insects of Is. Gangwha-do (Mt. Goryeo-san, 436 m) as well as some nearby islands (Is. Gyodong-do, Is. Boleum-do, Is. Jumun-do and Is. Seokmo-do (Mt. Haemyeong-san, 327 m)) through June and September, 2009. A total of 206 insects of 104 species of 38 families and 6 orders was investigated by this survey
Anti-amyloidogenic effect of menaquinone-7 on betaamyloid production and aggregation
Purpose: To investigate the beneficial effects of menaquinone-7 (MK-7), an isoform of vitamin K2, against beta-amyloid (Aβ) production and aggregation in Alzheimer's disease using in vitro assays. Methods: The cytotoxicity of MK-7 was determined by MTT assay. The amount of Aβ produced and secreted into the supernatant by APP-CHO cells treated with MK-7 was evaluated by ELISA. The expression of β-secretases and ADAM10, a representative α-secretase, was determined using western blot analysis. The production of sAPPβ and sAPPα fragments generated by β-secretases and αsecretase, respectively, were also determined by western blot analysis. The effect on Aβ aggregation was assessed using Thioflavin T (Th T) assay. Results: MK-7 (up to 75 nM) significantly decreased Aβ production in APP-CHO cells. This was accompanied by decreased expression of β-secretase and lower production of sAPPβ (p < 0.05). However, expression of ADAM10 and production of sAPPα were not significantly affected. In contrast, MK-7 significantly decreased Aβ aggregation in a dose-dependent manner (p < 0.05). Conclusion: MK-7 exerts anti-amyloidogenic effects via decreased production and lower aggregation of Aβ into oligomers and fibrils. Therefore, dietary supplementation with MK-7 may be beneficial for the prevention of Alzheimer’s disease
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