• JSTS:Journal of Semiconductor Technology and Science
• /
• 제14권4호
• /
• pp.383-390
• /
• 2014

This paper presents an excitatory CMOS neuron oscillator circuit design, which can synchronize two neuron-bursting patterns. The excitatory CMOS neuron oscillator is composed of CMOS neurons and CMOS excitatory synapses. And the neurons and synapses are connected into a close loop. The CMOS neuron is based on the Hindmarsh-Rose (HR) neuron model and excitatory synapse is based on the chemical synapse model. In order to fabricate using a 0.18 um CMOS standard process technology with 1.8V compatible transistors, both time and amplitude scaling of HR neuron model is adopted. This full-chip integration minimizes the power consumption and circuit size, which is ideal for motion control unit of the proposed bio-mimetic micro-robot. The experimental results demonstrate that the proposed excitatory CMOS neuron oscillator performs the expected waveforms with scaled time and amplitude. The active silicon area of the fabricated chip is $1.1mm^2$ including I/O pads.

• BMB Reports
• /
• 제38권3호
• /
• pp.290-293
• /
• 2005

In order to investigate the epitope of basic fibroblast growth factor (bFGF) and its immunogenicity, the epitopes of bFGF were screened from the phage display library with monoclonal antibody GF22, which can neutralize the bio-activity of bFGF. By three rounds of screening, the positive phage clones with bFGF epitopes were selected, which can effectively block the bFGF to bind with GF22. Sequence analysis showed that the epitopes shared a highly conservative sequence (Leu-Pro-Pro/Leu-Gly-His-Phe/Ile-Lys). The sequence of PPGHFK was located at 22-27 of the bFGF. The specific immuno-response of mouse could be highly induced by phage clones with the epitopes. And the anti-bFGF activity induced by LPGHFK was 3 times higher than the original sequence, which showed that the mimetic peptide LPLGHIK might be used as a tumor vaccine in the prevention and treatment of tumor.

• 약학회지
• /
• 제54권5호
• /
• pp.392-397
• /
• 2010

The aim of present study was to investigate the possible influence and related mechanism of additional alcohol on the flavonoid- induced arterial relaxation. Agonist-induced vascular smooth muscle contractions involve the activation of thick or thin filament pathway. However, there are no reports addressing the question whether this pathway is involved in quercetin-induced relaxation cotreated with alcohol in rat aortae contracted with phorbol ester, fluoride or thromboxane $A_2$ mimetic U-46619. We hypothesized that cotreated alcohol plays a role in vascular relaxation evoked by quercetin in rat aortae. Endothelium-denuded arterial rings from male Sprague-Dawley rats were used and isometric contractions were recorded using a computerized data acquisition system. Quercetin inhibited phorbol ester, fluoride or thromboxane $A_2$-induced contraction regardless of endothelial function. However, alcohol didn't decrease any agonist-induced contraction. Interestingly, only in thromboxane $A_2$-induced contraction, synergistic results were observed in aortae denuded and cotreated with quercetin and alcohol suggesting that additional pathways different from antioxidation or endothelial nitric oxide synthesis might be involved in the vasorelaxation. In conclusion, in the agonists-contracted rat aortae, quercetin and alcohol together showed synergistic response regardless of endothelial function in an agonist-dependent manner.

• Molecules and Cells
• /
• 제27권2호
• /
• pp.191-198
• /
• 2009

The present study was undertaken to determine whether treatment with genistein, the plant-derived estrogen-like compound influences agonist-induced vascular smooth muscle contraction and, if so, to investigate related mechanisms. The measurement of isometric contractions using a computerized data acquisition system was combined with molecular experiments. Genistein completely inhibited KCl-, phorbol ester-, phenylephrine-, fluoride- and thromboxane $A_2$-induced contractions. An inactive analogue, daidzein, completely inhibited only fluoride-induced contraction regardless of endothelial function, suggesting some difference between the mechanisms of RhoA/Rho-kinase activators such as fluoride and thromboxane $A_2$. Furthermore, genistein and daidzein each significantly decreased phosphorylation of MYPT1 at Thr855 had been induced by a thromboxane $A_2$ mimetic. Interestingly, iberiotoxin, a blocker of large-conductance calcium-activated potassium channels, did not inhibit the relaxation response to genistein or daidzein in denuded aortic rings precontracted with fluoride. In conclusion, genistein or daidzein elicit similar relaxing responses in fluoride-induced contractions, regardless of tyrosine kinase inhibition or endothelial function, and the relaxation caused by genistein or daidzein was not antagonized by large conductance $K_{Ca}$-channel inhibitors in the denuded muscle. This suggests that the RhoA/Rho-kinase pathway rather than $K^+$- channels are involved in the genistein-induced vasodilation. In addition, based on molecular and physiological results, only one vasoconstrictor fluoride seems to be a full RhoA/Rho-kinase activator; the others are partial activators.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2001년도 하계학술대회 논문집 D
• /
• pp.2744-2746
• /
• 2001

이 논문에서는 이동 로봇을 위하여 퍼지이론과 Dempster-Shafer 이론을 이용한 불확실한 환경에서의 센서기반 네비게이션 방법을 제안한다. 제안된 제어기는 장애물 회피 동작과 목적지 찾기 동작을 위한 2개의 행동 모듈로 구성되어 있다. 2개의 행동 모듈은 각각 퍼지 이론으로 학습되었고, 적절한 행동 선택 방법으로 선택되게끔 하였다. 견고한 퍼지 제어기를 가진 로봇이 실험 환경내에서 안전하게 움직이기 위하여 자동으로 지도를 구축(Map Building) 하도록 하였다. 이 실험에서 구성된 맵은 평면상의 격자를 중심으로 작성되었고 로봇의 센서에서 읽어들인 센서 값은 D-S 추론 이론을 이용하여 기존의 맵과 혼합되어진다. 즉, 로봇이 움직일때 마다 실험 환경내에서 새로운 정보를 읽어 들이고, 그 정보로 인하여 기존의 지도가 새로운 지도로 갱신되는 것이다. 이러한 작업을 거치면서 로봇은 장애물과 충돌없이 배회하는 것 뿐 아니라 설정된 목적지까지도 쉽게 찾아갈 수가 있다. 실험에 대한 안정성과 확신을 검증 받기 위하여 실제 로봇에 적용하기보다는 먼저 이동 로봇의 시뮬레이션으로 실험 해 보고자 한다.

• 한국지능시스템학회논문지
• /
• 제19권5호
• /
• pp.622-628
• /
• 2009

다족로봇이 보행하기 위해서는 기본적으로 어떤 보행 패턴의 설정이 필요하다. 이러한 관점에서 어떤 보행 패턴이 효과적인 다족 보행을 가능하게 할 것인지를 분석하기 위하여 본 논문은 네 개의 다리를 이용하는 4족 보행 로봇 모델을 고려하며, 보행 순간마다 지지판에 의해 형성되는 지시다각형의 중심경로를 기반으로 보행 밸런스를 분석한다. 또한, 다족 로봇의 보행 밸런스를 평가하기 위한 성능지수를 제안한다. 시뮬레이션을 통하여, 4족 로봇의 보행에서 지지다각형의 중심 경로와 보행 밸런스는 사용된 보행 패턴에 따라 다르다는 사실을 보인다. 결과적으로, 보행 밸런스 지수와 생체모방 관점으로부터 4족 로봇의 보행을 위하여 유용한 보행 패턴을 제시한다.

• 약학회지
• /
• 제50권4호
• /
• pp.293-299
• /
• 2006

The aim of present study was to investigate the possible influence of Rho-kinase inhibition on the plant-derived estrogen-like compounds-induced arterial relaxation. Agonist- or depolarization-induced vascular smooth muscle contractions involve the activation of Rho-kinase pathway. However there are no reports addressing the question whether this pathway is involved in genistein-or daidzein-induced vascular relaxation in rat aortae precontracted with phenylephrine or thromboxane $A_2$ mimetic U-46619. We hypothesized that Rho-kinase inhibition plays a role in vascular relaxation evoked by genistein or daidzein in rat aortae. Endothelium-intact and denuded arterial rings from male Sprague-Dawley rats were used and isometric contractions were recorded using a computerized data acquisition system. Genistein concentration-dependently inhibited phenylephrine or thromboxane $A_2-induced$ contraction regardless of endothelial function. Surprisingly, in the agonists-induced contraction, similar results were also observed in aortae treated with daidzein, the inactive congener for protein tyrosine kinase inhibition, suggesting that Rho-kinase might act upstream of tyrosine kinases in phenylephrine-induced contraction. In conclusion, in the agonists-precontracted rat aortae, genistein and daidzein showed similar relaxant response regardless of tyrosine kinase inhibition or endothelial function.

• 대한건축학회논문집:계획계
• /
• 제34권12호
• /
• pp.77-84
• /
• 2018

Biomimicry architecture has been highlighted in recent years for the innovative ideas from the nature have provided main developments in many areas. The related studies in Korean architecture is entering the first step and are needed close attentions for its vitalizations. This study starts with the acknowledgement of necessity to establish the architectural application process. First of all, it is named as a 'Passive Cycle' if a problem-solving or a project has been through the analysis of process complexity and biomimicry application process in other areas. Then, the basic frame is structured as a 'Process-Cooperation,' which integrates process complexation with process circulation. The cooperative relationship starts from the beginning of the design with not only professionalists related with architecture but also ones in various areas when it is issued a difficult problem or high environmental performance not found in common architectural design processes. To make the architectural application good progress, the characteristics of bio-mimetic architectural applications are categorized as three areas; the expected effect, the application level, and application method. As a result, the organic complexity should be prioritized to have bio-mimetic application effectively while accessing the principles. Therefore, the process for the architectural application of biomimicry is suggested as 'Organic Cycle-Cooperation.'

• Journal of Applied Biological Chemistry
• /
• 제62권4호
• /
• pp.417-424
• /
• 2019

이 연구의 목적은 당 대사에 대한 삼색싸리(Lespedeza maximowiczii var. tricolor Nakai; LMTN)의 효과를 조사하는 것이다. LMTN 추출물은 대조군과 비교하여 3T3-L1 지방 세포에서 당 섭취능 및 지질축적을 유의하게 향상시켰다. 또한, 3T3-L1 지방 세포에서 LMTN 추출물은 퍼옥시좀 증식제 활성화 수용체(PPAR)γ, 인슐린수용체기질-1 (IRS-1) 및 포도당수송체(GLUT)4의 단백질 발현을 유의하게 증가시켰다. LMTM 추출물의 당 섭취능 또는 인슐린 신호 전달계의 조절 효과는 양성 대조물질인 트로글리타존 또는 피니톨보다 낮았지만 PPARγ 단백 활성화는 증가하였다. 또한, LMTM 추출물은 인슐린 유사효과를 나타냈다. db/db 마우스에서, LMTN 추출물(250 mg/kg BW)은 물과 식이 섭취량, 혈당, 중성지방과 총 콜레스테롤 함량을 유의적으로 감소시켰다. 더불어 지방과 근육조직에서의 PPARγ 및 GLUT4 mRNA의 발현도 LMTN 추출물 투여군에서 유의적으로 증가되었다. 따라서, 본 연구의 결과는 LMTN 추출물이 3T3-L1 지방세포 및 db/db 마우스에서 PPARγ 및 인슐린 유사효과를 통해 당 대사를 조절하는 것으로 밝혀졌다.

• 한국지능시스템학회:학술대회논문집
• /
• 한국지능시스템학회 2007년도 추계학술대회 학술발표 논문집
• /
• pp.159-162
• /
• 2007

The inverse kinematics problem in robotics is an essential work for grasping and manipulation tasks by robotic and humanoid hands. In this paper, an intelligent neural learning scheme for solving such inverse kinematics of humanoid fingers is presented. Specifically, a multi-layered neural network is utilized for effective inverse kinematics, where a dynamic neural learning algorithm is employed. Also, a bio-mimetic feature of general human fingers is incorporated to the learning scheme. The usefulness of the proposed approach is verified by simulations.