• Title/Summary/Keyword: Biological aspects

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조직공학에서 생체역학의 역할 (The Role of Biomechanics in Tissue Engineering)

  • 박귀덕
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1458-1460
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    • 2008
  • Tissue engineering is an interdisciplinary field that utilizes the principles of engineering and life sciences toward the creation of biological substitutes. Traditionally, major components of tissue engineering are cells, scaffolds, growth factors and recently biomechanical aspects have been given much attention. A large number of studies have reported that mechanical signals are of particular interest in either encouraging or inhibiting cellular responses. In tissue engineering, cell adhesion is a very important step, because quality of adhesion may determine a cell fate in the future. Elasticity of cell-adhesive substrate is found critical in regulating stem cell differentiation. Cells exert different contractile forces for cell migration, depending on substrate mechanics. Though tissue engineering is very interactive with diverse expertise, for a breakthrough, principles of biomechanics in tissue and cell level needs to be fully understood.

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ENDOSCOPE A/V SYSTEM 개선에 관한 연구 (THE STUDY ABOUT THE ENDOSCOPE A/V SYSTEM IMPROVEMENT)

  • 채영한;박현상;천승민;김영서;전석봉;권혁남
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1998년도 추계학술대회
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    • pp.102-103
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    • 1998
  • Various Endoscope Video System have been introduced and used at wide fields in our country. But this system doesn't have fuction available for recording of Video and Audio data at a time. So many problems were caused by this point, like loose of data accuracy, time and manpower consumption for re-editing prodedure and so on. For solving these problems, we made and modified some systems considering economical and practical aspects and tried to lift up efficiency of clinical usage.

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Measurement of Secondary Electron Emission Coefficient and Bimolecular Valence Band Energy Structure of Erythrocyte with and Without Bioplasma Treatment

  • Lee, Jin-Young;Baik, Guyon;Choi, Eun-Ha
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.483-483
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    • 2012
  • Recently, nonthermal bioplasma has been attracted by researchers due to their potentials to modulate cellular functions resulting in changes of biomolecular electron band structures as well as cell morphologies. We have investigated the secondary electron emission characteristics from the surface of the erythrocyte, i.e., red blood cell (RBC) with and without the nonthermal bioplasma treatment in morphological and biomolecular aspects. The morphologies have been controlled by osmotic pressure and biomolecular structures were changed by well known reactive oxygen species. Ion-induced secondary electron emission coefficient have been measured by using gamma-focused ion beam (${\gamma}$-FIB) system, based on the quantum mechanical Auger neutralization theory. Our result suggests that the nonthermal bioplasma treatment on biological cells could result in change of the secondary electron emission coefficient characterizing the biomolecular valence band electron energy structures caused by the cell morphologies as well as its surface charge distributions.

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의수 제어를 위한 HMM-MLP 근전도 신호 인식 기법 (An EMG Signals Discrimination Using Hybrid HMM and MLP Classifier for Prosthetic Arm Control Purpose)

  • 권장우;홍승홍
    • 대한의용생체공학회:의공학회지
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    • 제17권3호
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    • pp.379-386
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    • 1996
  • This paper describes an approach for classifying myoelectric patterns using a multilayer perceptrons (MLP's) and hidden Markov models (HMM's) hybrid classifier. The dynamic aspects of EMG are important for tasks such as continuous prosthetic control or vari- ous time length EMG signal recognition, which have not been successfully mastered by the most neural approaches. It is known that the hidden Markov model (HMM) is suitable for modeling temporal patterns. In contrasts the multilayer feedforward networks are suitable for static patterns. Ank a lot of investigators have shown that the HMM's to be an excellent tool for handling the dynamical problems. Considering these facts, we suggest the combination of MLP and HMM algorithms that might lead to further improved EMG recognition systems.

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알레로파시 연구의 기초와 전망 (Basic and Prospective Aspects on Allelopathic Research)

  • 길봉섭
    • 한국환경생태학회:학술대회논문집
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    • 한국환경생태학회 2005년도 정기총회 및 학술대회
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    • pp.3-14
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    • 2005
  • To investigate phytotoxic substances in some donor plants and their biological activities, seed germination and seedling growth of receptor plants were examined at different concentrations of aqueous extracts and essential oils of the donor plants. Germination of some receptor species was inhibited by the extracts, while seedling growth was decreased to a lesser degree than in the germination test. Germination, seedling growth and dry weight growth of Achyranthes japonica grown in pot were proportionally inhibited by the extracts. Volatile substances emitted some donor plants caused inhibitory effects in the germination and seedling growth of the receptor species. Essential oil of the plants extracted by Karlsruker's apparatus Inhibited growth of microorganisms, callus growth and root hair development of receptor plants. The cortical cells at the root tips of Latuca sativa treated with essential oils showed contraction of the cytoplasm, resulting in plasma membranes becoming detached from the cell walls and the cells metamorphosing irregularity. Accumulation of lipid granules Inside contracted cytoplasm and degeneration of mitochondrial cristae were also observed. The GC/MS method was employed for analysis and identification of allelochemicals from donor plants. Sixty-one chemical substances such as camphene, cineole etc. were identified from essential oils of Artemisia argyi.

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Development of Information Biology (I)

  • Tateno, Yoshio
    • Interdisciplinary Bio Central
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    • 제5권1호
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    • pp.2.1-2.3
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    • 2013
  • Birth and development of information biology are introduced with its definition and scientific basis. The discipline lives on the two types of nutrition, one is a huge amount of biological data on genomes, gene expressions, proteomes, protein 3D structures, protein networks, and so forth. The other is the method of using them on a computer. The scientific basis of the two is evolution. To collect genome and gene expression data form laboratories in the world, annotate and dissimilate back to researchers worldwide, they built the EMBL database in Europe in 1982, GenBank in USA in 1984 and DNA Data Bank of Japan in 1987. On the other hand, the methods of using and analyzing those data have accordingly been developed. The two aspects advance the discipline further and further.

Valerian의 구성성분 및 이소발레르아미드에 관한 연구 (Studies on the Components of Valerian and Isovaleramide)

  • 박현정;이상협
    • 약학회지
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    • 제54권1호
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    • pp.1-7
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    • 2010
  • Valerian (Valeriana officinalis L.) is a perennial that has been used for medicinal purposes from the ancient times and valerian preparations including root and rhizome extracts are known to possess a variety of biological activities such as anticonvulsant, antidepressant, sleep aid, tranquilizer, and anti-HIV activities. Main components of the extracts were classified according to the structural features. Importantly, one of the main components, isovaleramide, has drawn our attention due to the concise structure, broad spectrum, and low toxicities. The general aspects including generation of this interesting molecule, a variety of activities, pharmacokinetic properties, derivatization, and fusion with other known drugs were described. Isovaleramide has been isolated from valerian probably as an isolation artifact after treatment of ammonia to prepare ammoniated tincture, and is known to exhibit anticonvulsant, anxiolytic, sedative, and sleep aid activities without distinct side effects such as excessive sedation and decreasing muscle tone. It was also found to be well absorbed into the circulation system without specific cytotoxicity and genotoxicity. The derivatives of isovaleramide, valpromide, valrocemide and valnoctamide were also briefly discussed.

Structural Studies of G Protein-Coupled Receptors

  • Zhang, Dandan;Zhao, Qiang;Wu, Beili
    • Molecules and Cells
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    • 제38권10호
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    • pp.836-842
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    • 2015
  • G protein-coupled receptors (GPCRs) constitute the largest and the most physiologically important membrane protein family that recognizes a variety of environmental stimuli, and are drug targets in the treatment of numerous diseases. Recent progress on GPCR structural studies shed light on molecular mechanisms of GPCR ligand recognition, activation and allosteric modulation, as well as structural basis of GPCR dimerization. In this review, we will discuss the structural features of GPCRs and structural insights of different aspects of GPCR biological functions.

Policy measures and necessities for small scale organic farming in the EU

  • Cho, Y.;Nicholas, P.
    • 한국유기농업학회지
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    • 제19권spc호
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    • pp.115-118
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    • 2011
  • Most of European countries have certain support measures of small holder organic producers in their policy system but they need to be more positive with this issue. Recent EU regulations and any other governmental organic farming measures are hardly emphasising on small holders' issues except a few measures. In order to secure small producer organic farming, the extensive efforts are needed. Developing new logos and differential support system for small producer organic at every aspects from production, marketing and public procurement level will become more positive actions to take, for example.

Biological Image Edge Extraction Based on Adaptive Beamlet Transform

  • Nguyen, Van Hau;Woo, Kyung-Haeng;Choi, Won-Ho
    • 융합신호처리학회논문지
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    • 제12권2호
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    • pp.83-90
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    • 2011
  • In cell biology area, microscopy enables detecting objects inside cells that are stained or fluorescently tagged. It is disadvantageous for observing these objects because of the noisy characteristics of their environmental surrounding. In this paper, a framework is proposed to increase the throughput and reliability for analysis of these images. First, we apply adaptive beamlet transform to extract edges meaningfully followed by orientation, location, and length in different scales. Then, a post-process is implemented to extend and map them onto original image. Our proposed scheme is compared with Canny edge detector and conventional beamlet transform from four evaluation aspects. It produces better results when experiments are conducted on real images. Much better results for observing internal parts make this framework competitive for analysis of cell images.