• Title/Summary/Keyword: Information cascade

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A Long-day-stimulus Induced the Expression of c-Fos-like Molecules in the Hypothalamus of Japanese quail

  • Okano, Keiko;Okano, Toshiyuki;Oishi, Tadashi;Fukada, Yoshitaka
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.255-257
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    • 2002
  • In birds, the photoperiodic seasonal breeding involves encephalic photoreception at the initial step of triggering the well-known endocrinal cascade. Especially in Japanese quail (Coturnix coturnixjaponica), the reproductive neuroendocrine function responds to a single long day, and hypothalamic regions are known to be important for the reproductive response. However, little is known about where and how the light and time signals are integrated to detect daylength information and transduced to the endocrinal responses. To gain insights into this issue, we are interested in the c-Fos expression in the hypothalamus of the Japanese quail. Meddle and Follett (1997) previously identified two hypothalamic regions where c-Fos-like immunoreactivities were induced in response to a long day by using an antibody to carboxyl terminal region of human c-Fos (Lys$^{347}$ -Leu$^{367}$ ). In the present study, we used a different anti-c-Fos antibody recognizing a region from Lys$^{128}$ to Ala$^{152}$ of human c-Fos, and found in long-day- stimulated quails many c-Fos-like immunoreactive nuclei localizing within two regions, nucleus anterior medialis hypothalami and nucleus periventricularis hypothalami, which are distinct from those identified in the previous study. Then, we focused on the difference in the cross-reactivities of the antibodies used, and determined the whole coding sequence of quail c-Fos to compare the antigenic sequences of the two antibodies with the amino acid sequence of quail c-Fos. We found that the antibody we used would recognize quail c-Fos more specifically than that used in the previous study.

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Molecular Cloning and Expression of Forkhead Transcription Factor O1 Gene from Pig Sus scrofa

  • Pang, Weijun;Sun, Shiduo;Bai, Liang;Yang, Gongshe
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.4
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    • pp.499-509
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    • 2008
  • Foxo1 plays an important role in the integration of hormone-activated signaling pathways with the complex transcriptional cascade that promotes preadipocyte differentiation of clonal cell lines from rodents. We isolated the full-length cDNA of porcine FoxO1 gene using RACE, confirmed by visual Northern blotting. The deduced amino acids indicated 94% and 90% identities with the corresponding human and mice aa. Analysis of the aa sequence, showed that it included a Forkhead domain (aa 167-247), a transmembrane structure domain (aa 90-113), a LXXLL motif (aa 469-473), and 51 Ser, 8 Thr, and 4 Tyr phosphorylation sites, indicating a potential important role for FoxO1 transcriptional activity in vivo. Using the IMpRH panel, we mapped FoxO1 gene to chromosome 11p13. Our data provide basic molecular information useful for the further investigation on the function of FoxO1 gene. Time-course analysis of FoxO1 expressions indicated that levels of mRNA and protein gradually increased from day 0 to 3, and it reached almost maximal level at day 3, then decreased from day 5 to 7 in porcine primary preadipocyte differentiation. After induction by IGF-1, GPDH activity and accumulation of lipid increased, however, expressions of FoxO1 mRNA and protein were inhibited in a dose dependent manner. These results suggest that FoxO1 takes part in porcine preadipocyte differentiation and expressions of FoxO1 were regulated by IGF-1.

A Low-Voltage Low-Power Delta-Sigma Modulator for Cardiac Pacemaker Applications (심장박동 조절장치를 위한 저전압 저전력 델타 시그마 모듈레이터)

  • Chae, Young-Cheol;Lee, Jeong-Whan;Lee, In-Hee;Han, Gun-Hee
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.1
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    • pp.52-58
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    • 2009
  • A low voltage, low power delta-sigma modulator is proposed for cardiac pacemaker applications. A cascade of delta-sigma modulator stages that employ a feedforward topology has been used to implement a high-resolution oversampling ADC under the low supply. An inverter-based switched-capacitor circuit technique is used for low-voltage operation and ultra-low power consumption. An experimental prototype of the proposed circuit has been implemented in a $0.35-{\mu}m$ CMOS process, and it achieves 61-dB SNDR, 63-dB SNR, and 65-dB DR for a 120-Hz signal bandwidth at 7.6-kHz sampling frequency. The power consumption is only 280 nW at 1-V power supply.

Massive Parallel Processing Algorithm for Semiconductor Process Simulation (반도체 공정 시뮬레이션을 위한 초고속 병렬 연산 알고리즘)

  • 이제희;반용찬;원태영
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.36D no.3
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    • pp.48-58
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    • 1999
  • In this paper, a new parallel computation method, which fully utilize the parallel processors both in mesh generation and FEM calculation for 2D/3D process simulation, is presented. High performance parallel FEM and parallel linear algebra solving technique was showed that excessive computational requirement of memory size and CPU time for the three-dimensional simulation could be treated successively. Our parallelized numerical solver successfully interpreted the transient enhanced diffusion (TED) phenomena of dopant diffusion and irregular shape of R-LOCOS within 15 minutes. Monte Carlo technique requires excessive computational requirement of CPU time. Therefore high performance parallel solving technique were employed to our cascade sputter simulation. The simulation results of Our sputter simulator allowed the calculation time of 520 sec and speedup of 25 using 30 processors. We found the optimized number of ion injection of our MC sputter simulation is 30,000.

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Sigma-Pi$_{t}$ Cascaded Hybrid Neural Network and its Application to the Spirals and Sonar Pattern Classification Problems

  • Iyoda, Eduardo-Masato;Hajime Nobuhara;Kazuhiko Kawamoto;Shin′ichi Yoshida;Kaoru Hirota
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2003.09a
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    • pp.158-161
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    • 2003
  • A cascade structured neural network called Sigma-Pi$_{t}$ Cascaded Hybrid Neural Network ($\sigma$$\pi$$_{t}$-CHNN) is Proposed. It is an extended version of the Sigma-Pi Cascaded extended Hybrid Neural Network ($\sigma$$\pi$-CHNN), where the classical multiplicative neuron ($\pi$-neuron) is replaced by the translated multiplicative ($\pi$$_{t}$-neuron) model. The learning algorithm of $\sigma$$\pi$$_{t}$-CHNN is composed of an evolutionary programming method, responsible for determining the network architecture, and of a Levenberg-Marquadt algorithm, responsible for tuning the weights of the network. The $\sigma$$\pi$$_{t}$-CHNN is evaluated in 2 pattern classification problems: the 2 spirals and the sonar problems. In the 2 spirals problem, $\sigma$$\pi$$_{t}$-CHNN can generate neural networks with 10% less hidden neurons than that in previous neural models. In the sonar problem, $\sigma$$\pi$$_{t}$-CHNN can find the optimal solution for the problem i.e., a network with no hidden neurons. These results confirm the expanded information processing capabilities of $\sigma$$\pi$$_{t}$-CHNN, when compared to previous neural network models. network models.

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Inhibitory Effect of Capsaicin on Interleukin-8 Production by Helicobacter pylori-Infected MKN-45 Cells

  • Lee, Kwang-Hyoung;Lee, Yong-Chan;Kim, Tae-Il;Noh, Sung-Hoon;Kim, Ji-Yeon;Paik, Hyun-Dong;Kim, Chang-Han
    • Journal of Microbiology and Biotechnology
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    • v.16 no.7
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    • pp.1078-1083
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    • 2006
  • Capsaicin is the active ingredient in chili pepper and has an inhibitory effect on Helicobacter pylori growth and $NF-{\kappa}B$ activation. The present study examined the effect of capsaicin on interleukin (IL)-8 production by H. pylori ATCC 43504-infected MKN-45 cells, a gastric epithelial cell line. The viability of the MKN-45 cells treated with capsaicin at 0, 50, 100, 250, and $500\;{\mu}M$ was 99, 98, 99, 99, and 85%, respectively. A capsaicin concentration as low as $50\;{\mu}M$ significantly inhibited the IL-8 production induced by H. pylori ATCC 43504 infection (43.2% of control) during 24 h of incubation. However, low concentrations of capsaicin $(50\;and\;100{\mu}M)$ did not significantly inhibit the IL-8 production by $TNF-{\alpha}-$ or PMA-treated MKN-45 cells. Therefore, the overall inhibitory effect of capsaicin on H. pylori ATCC 43504 was the sum of H. pylori ATCC 43504 growth inhibition, host cell survival, and $NF-{\kappa}B$ signal cascade inhibition.

An Efficient Adaptive Polarization-Space-Time Domain Radar Target Detection Algorithm (3차원 (편파, 공간, 시간) 영역에서의 효율적인 적응 레이다 신호검출 알고리즘)

  • Yang, Yeon-Sil;Lee, Sang-Ho;Yoon, Sang-Sik;Park, Hyung-Rae
    • Journal of Advanced Navigation Technology
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    • v.6 no.2
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    • pp.138-150
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    • 2002
  • This paper addresses the problem of combining adaptive polarization processing and space-time processing for further performance improvement of radar target detection in clutter and Jammer environments. Since the most straightforward cascade combinations have quite limited performance improvement potentials, we focus on the development of adaptive processing in the joint polarization-space-time domain. Unlike a direct extension of some existing space-time processing algorithms to the joint domain, the processing algorithm developed in this paper does not need a potentially costly polarization filter bank to cover the unknown target polarization parameter. The performance of the new algorithm is derived and evaluated in terms of the probability of detection and the probability of false alarm, and it is compared with other algorithms that do not utilize the polarization information or assume that the target polarization is known.

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Attenuator using Lossy Left-Handed Transmission Line and Vector Modulator Application (손실이 있는 Left-Handed 전송선로를 이용한 감쇠기와 벡터 변조기 응용)

  • Kim, Seung-Hwan;Kim, Ell-Kou;Kim, Young;Yoon, Young-Chul
    • Journal of Advanced Navigation Technology
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    • v.13 no.3
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    • pp.399-405
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    • 2009
  • This paper proposes a design of attenuator based on meta-material structure and its application. The unit-cell attenuator based on the lossy transmission line consists of the CRLH(Composite Right/Left Handed) transmission line and PIN diodes to be controlled internal loss according to diode bias voltage to change resistance of diode. Also, to reduce the initial losses, there is used parallel connection of PIN diodes. To increase attenuations, it is connected a cascade unit-cell of attenuator with periodic structure. The attenuation quantities of unit-cell are about 10dB and phase variations are 15o maximum at 1.5 GHz ~ 2.5 GHz. Also, its application is represented a vector modulator.

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Multi-Scaling Models of TCP/IP and Sub-Frame VBR Video Traffic

  • Erramilli, Ashok;Narayan, Onuttom;Neidhardt, Arnold;Saniee, Iraj
    • Journal of Communications and Networks
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    • v.3 no.4
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    • pp.383-395
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    • 2001
  • Recent measurement and simulation studies have revealed that wide area network traffic displays complex statistical characteristics-possibly multifractal scaling-on fine timescales, in addition to the well-known properly of self-similar scaling on coarser timescales. In this paper we investigate the performance and network engineering significance of these fine timescale features using measured TCP anti MPEG2 video traces, queueing simulations and analytical arguments. We demonstrate that the fine timescale features can affect performance substantially at low and intermediate utilizations, while the longer timescale self-similarity is important at intermediate and high utilizations. We relate the fine timescale structure in the measured TCP traces to flow controls, and show that UDP traffic-which is not flow controlled-lacks such fine timescale structure. Likewise we relate the fine timescale structure in video MPEG2 traces to sub-frame encoding. We show that it is possibly to construct a relatively parsimonious multi-fractal cascade model of fine timescale features that matches the queueing performance of both the TCP and video traces. We outline an analytical method ta estimate performance for traffic that is self-similar on coarse timescales and multi-fractal on fine timescales, and show that the engineering problem of setting safe operating points for planning or admission controls can be significantly influenced by fine timescale fluctuations in network traffic. The work reported here can be used to model the relevant characteristics of wide area traffic across a full range of engineering timescales, and can be the basis of more accurate network performance analysis and engineering.

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Low-area FFT Processor Structure using $Radix-4^2$ Algorithm ($Radix-4^2$알고리즘을 사용한 저면적 FFT 프로세서 구조)

  • Kim, Han-Jin;Jang, Young-Beom
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.49 no.3
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    • pp.8-14
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    • 2012
  • In this paper, a low-area FFT structure using $Radix-4^2$ algorithm is proposed. The large point FFT structure consists of cascade connection of the many stages. In implementation of large point FFT using $Radix-4^2$ algorithm, stages which number of different coefficients are only 3 appear in every 2 stages. For example, in the 4096-point FFT, the stages that number of different coefficients are 3 appear in stage 1, 3, and 5 among 6 stages. Multiplication block area of these 3 stages can be reduced using CSD(Canonic Signed Digit) and common sub-expression sharing techniques. Using the proposed structure, the 256-point FFT is implemented with the Verilog-HDL coding and synthesized by $1.971mm^2$ cell area in tsmc $0.18{\mu}m$CMOS library. This result shows 23% cell area reduction compared with the conventional structure.