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"Supersolidity flows back," Nature, September 2, 2010
Supersolidity, discovered for the first time in 2004 by two physicists—one of them is Professor Eun-Seong Kim from the Department of Physics, KAIST—was discussed once again in the September 2, 2010 issue of Nature, an internationally well-known science journal. The article mentioned “supersolidity” as one of the rare examples of quantum effects on a macroscopic scale, together with “superconductivity” and “superfluidity.” The phenomenon of supersolidity was evidenced by Professor Kim and his colleague through an experiment of placing helium-4 in a torsional oscillator under a low temperature. The phenomenon, however, has been in debate among scientists in the physics community since the discovery, and Professor Kim has recently released his research results to further support his claim. For the full article, please click the link below: http://www.nature.com/news/2010/100902/full/news.2010.443.html.
2010.09.08
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Science News Issued on September 11, 2010: A matter of solidity
Science News, a bi-weekly news magazine of the Society for Science & the Public, published an extensive article on the issue of “supersolidity” discovered in helium-4. Professor Eun-Seong Kim of the Physics Department, KAIST, is one of the scientists who discovered the phenomenon through an experiment of solid helium using a device called a torsional oscillator. For the entire article, please click the link of http://www.sciencenews.org/view/feature/id/62642/title/A_matter_of_solidity.
2010.09.02
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Nanowire crystal transformation method was newly developed by a KAIST research team.
Figure 1 Schematic illustration of NW crystal transformation process. FeSi is converted to Fe3Si by high-temperature thermal annealing in diluted O2 condition and subsequent wet etching by 5% HF. Figure 2 Low-resolution TEM images of FeSi; Fe3Si@SiO2 core—shell; Fe3Si NW after shell-etching; and Scale bars are 20 nm Professor Bongsoo Kim of the Department of Chemistry, KAIST, and his research team succeeded to fabricate Heusler alloy Fe3Si nanowires by a diffusion-driven crystal structure transformation method from paramagnetic FeSi nanowires. This methodology is also applied to Co2Si nanowires in order to obtain metal-rich nanowires (Co) as another evidence of the structural transformation process. The newly developed nanowire crystal transformation method, Professor Kim said, would be valuable as a general method to fabricate metal-rich silicide nanowires that are otherwise difficult to synthesize. Metal silicide nanowires are potentially useful in a wide array of fields including nao-optics, information technology, biosensors, and medicine. Chemical synthesis of these nanowires, however, is challenging due to the complex phase behavior of silicides. The metal silicide nanowires are grown on a silicon substrate covered with a thin layer of silicon oxide via a simple chemical vapor deposition (CVD) process using single or multiple source precursors. Alternatively, the nanowires can be grown on the thin silicon oxide film via a chemical vapor transport (CVT) process using solid metal silicide precursors. The CVT-based method has been highly effective for the syntheses of metal silicide NWs, but changing the composition of metal silicide NWs in a wider range, especially achieving a composition of a metal to silicon, has been quite difficult. Thus, developing efficient and reliable synthetic methods to adjust flexibly the elemental compositions in metal silicide NWs can be valuable for the fabrication of practical spintronic and neonelectronic devices. Professor Kim expliained, “The key concept underlying this work is metal-enrichment of metal silicide NWs by thermal diffusion. This conversion method could prove highly valuable, since novel metal-rich silicide NWs that are difficult to synthesize but possess interesting physical properties can be fabricated from other metal silicide NWs.” The research result was published in Nanao Letters, a leading peer-reviewed journal, and posted online in early August 2010.
2010.08.25
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An internationally renowned academic journal published the research result produced by a KAST research team on its cover.
Fc DAAP VEGF-Trap Photograph showing the gross features of tumor growth along the mesentery-intestinal border. T: tumor. Scale bars represent 5 mm. Professor Gou-Young Koh of the Biological Sciences Department, KAIST, and his research team published their research result in Cancer Cell, a peer-review scientific journal, as a cover article dated August 17, 2010. It is the first time for the journal to pick up a paper written by a Korean research team and publish it as the cover. It has been known that a vascular growth factor (VEGF) is closely related to the growth of a tumor. The research team recently discovered that in addition to VEGF, another growth factor, angiopoietin-2 (Ang2), is also engaged with the increase of tumors. Professor Koh said, “VEGF and the angiopoietins play critical roles in tumor progression and metastasis, and a single inhibitor targeting both factors have not been available.” The team led by Professor Koh has developed a double anti-angiogenic protein (DAAP) that can simultaneously bind VEGF-A and the angiopoietins and block their actions. Professor Koh said in his paper, “DAAP is a highly effective molecule for regressing tumor angiogenesis and metastasis in implanted and spontaneous solid tumor; it can also effectively reduce ascites formation and vascular leakage in an ovarian carcinoma model. Thus, simultaneous blockade of VEGF-A and angiopoietins with DAAP is an effective therapeutic strategy for blocking tumor angiogenesis, metastasis, and vascular leakage.” So far, cancer patients have received Avastin, anticancer drug, to inhibit VEGF, but the drug has not successfully restrained the growth of cancer tumors and brought to some of the patients with serious side effects instead. Professor Koh said, “DAAP will be very effective to control the expansion of tumor growth factors, which will open up a new possibility for the development of more helpful cancer medicine with low side effects.”
2010.08.20
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Nature Photonics, a peer-reviewed scientific journal, released a paper written by a KAIST research team on the time-of-flight measurement.
Professor Seung-Woo Kim of the Mechanical Engineering Department, KAIST, and his research team published the result of their study on the measurement of 1 nanometer (nm) precision. “The time-of-flight of light pulses has long been used as a direct measure of distance, but state-of-the-art measurement precision using conventional light pulses or microwaves peaks at only several hundreds of micrometers. Here, we improve the time-of-flight precision to the nanometer regime by timing femtosecond pulses through phase-locking control of the pulse repetition rate using the optical cross-correlation technique,” Professor Kim said. According to the experiment conducted by the research team, “An Allan deviation of 117 nm in measuring a 700m distance in air at a sampling rate of 5 millisecond (ms) once the pulse repetition is phased-locked, which reduces to 7 nm as the averaging time increases to 1 second (s).” When measuring an object located in a far distance, a laser beam is projected to the object, and the reflected light is analyzed; the light is then converted into an electric signal to calculate the distance. In so doing, Professor Kim said, the conventional method of measurement creates at least 1 mm of deviation. He argues, “This enhanced capability is maintained at long range without periodic ambiguity, and is well suited to lidar applications. This method could also be applied to future space missions involving formation-flying satellites for synthetic aperture imaging and remote experiments related to general relativity theory." Nature Photonics published the article online on August 8, 2010.
2010.08.18
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Bioengineers develop a new strategy for accurate prediction of cellular metabolic fluxes
A team of pioneering South Korean scientists has developed a new strategy for accurately predicting cellular metabolic fluxes under various genotypic and environmental conditions. This groundbreaking research is published in the journal Proceedings of the National Academy of Sciences of the USA (PNAS) on August 2, 2010. To understand cellular metabolism and predict its metabolic capability at systems-level, systems biological analysis by modeling and simulation of metabolic network plays an important role. The team from the Korea Advanced Institute of Science and Technology (KAIST), led by Distinguished Professor Sang Yup Lee, focused their research on the development of a new strategy for more accurate prediction of cellular metabolism. “For strain improvement, biologists have made every effort to understand the global picture of biological systems and investigate the changes of all metabolic fluxes of the system under changing genotypic and environmental conditions,” said Lee. The accumulation of omics data, including genome, transcriptome, proteome, metabolome, and fluxome, provides an opportunity to understand the cellular physiology and metabolic characteristics at systems-level. With the availability of the fully annotated genome sequence, the genome-scale in silico (means “performed on computer or via computer simulation.”) metabolic models for a number of organisms have been successfully developed to improve our understanding on these biological systems. With these advances, the development of new simulation methods to analyze and integrate systematically large amounts of biological data and predict cellular metabolic capability for systems biological analysis is important. Information used to reconstruct the genome-scale in silico cell is not yet complete, which can make the simulation results different from the physiological performances of the real cell. Thus, additional information and procedures, such as providing additional constraints (constraint: a term to exclude incorrect metabolic fluxes by restricting the solution space of in silico cell) to the model, are often incorporated to improve the accuracy of the in silico cell. By employing information generated from the genome sequence and annotation, the KAIST team developed a new set of constraints, called Grouping Reaction (GR) constraints, to accurately predict metabolic fluxes. Based on the genomic information, functionally related reactions were organized into different groups. These groups were considered for the generation of GR constraints, as condition- and objective function- independent constraints. Since the method developed in this study does not require complex information but only the genome sequence and annotation, this strategy can be applied to any organism with a completely annotated genome sequence. “As we become increasingly concerned with environmental problems and the limits of fossil resources, bio-based production of chemicals from renewable biomass has been receiving great attention. Systems biological analysis by modeling and simulation of biological systems, to understand cellular metabolism and identify the targets for the strain improvement, has provided a new paradigm for developing successful bioprocesses,” concluded Lee. This new strategy for predicting cellular metabolism is expected to contribute to more accurate determination of cellular metabolic characteristics, and consequently to the development of metabolic engineering strategies for the efficient production of important industrial products and identification of new drug targets in pathogens.”
2010.08.05
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Native-like Spider Silk Produced in Metabolically Engineered Bacterium
Microscopic picture of 285 kilodalton recombinant spider silk fiber Researchers have long envied spiders’ ability to manufacture silk that is light-weighted while as strong and tough as steel or Kevlar. Indeed, finer than human hair, five times stronger by weight than steel, and three times tougher than the top quality man-made fiber Kevlar, spider dragline silk is an ideal material for numerous applications. Suggested industrial applications have ranged from parachute cords and protective clothing to composite materials in aircrafts. Also, many biomedical applications are envisioned due to its biocompatibility and biodegradability. Unfortunately, natural dragline silk cannot be conveniently obtained by farming spiders because they are highly territorial and aggressive. To develop a more sustainable process, can scientists mass-produce artificial silk while maintaining the amazing properties of native silk? That is something Sang Yup Lee at the Korea Advanced Institute of Science and Technology (KAIST) in Daejeon, the Republic of Korea, and his collaborators, Professor Young Hwan Park at Seoul National University and Professor David Kaplan at Tufts University, wanted to figure out. Their method is very similar to what spiders essentially do: first, expression of recombinant silk proteins; second, making the soluble silk proteins into water-insoluble fibers through spinning. For the successful expression of high molecular weight spider silk protein, Professor Lee and his colleagues pieced together the silk gene from chemically synthesized oligonucleotides, and then inserted it into the expression host (in this case, an industrially safe bacterium Escherichia coli which is normally found in our gut). Initially, the bacterium refused to the challenging task of producing high molecular weight spider silk protein due to the unique characteristics of the protein, such as extremely large size, repetitive nature of the protein structure, and biased abundance of a particular amino acid glycine. “To make E. coli synthesize this ultra high molecular weight (as big as 285 kilodalton) spider silk protein having highly repetitive amino acid sequence, we helped E. coli overcome the difficulties by systems metabolic engineering,” says Sang Yup Lee, Distinguished Professor of KAIST, who led this project. His team boosted the pool of glycyl-tRNA, the major building block of spider silk protein synthesis. “We could obtain appreciable expression of the 285 kilodalton spider silk protein, which is the largest recombinant silk protein ever produced in E. coli. That was really incredible.” says Dr. Xia. But this was only step one. The KAIST team performed high-cell-density cultures for mass production of the recombinant spider silk protein. Then, the team developed a simple, easy to scale-up purification process for the recombinant spider silk protein. The purified spider silk protein could be spun into beautiful silk fiber. To study the mechanical properties of the artificial spider silk, the researchers determined tenacity, elongation, and Young’s modulus, the three critical mechanical parameters that represent a fiber’s strength, extensibility, and stiffness. Importantly, the artificial fiber displayed the tenacity, elongation, and Young’s modulus of 508 MPa, 15%, and 21 GPa, respectively, which are comparable to those of the native spider silk. “We have offered an overall platform for mass production of native-like spider dragline silk. This platform would enable us to have broader industrial and biomedical applications for spider silk. Moreover, many other silk-like biomaterials such as elastin, collagen, byssus, resilin, and other repetitive proteins have similar features to spider silk protein. Thus, our platform should also be useful for their efficient bio-based production and applications,” concludes Professor Lee. This work is published on July 26 in the Proceedings of the National Academy of Sciences (PNAS) online.
2010.07.28
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The thermal fluctuation and elasticity of cell membranes, lipid vesicles, interacting with pore-forming peptides were reported by a research team at KAIST.
A research team from KAIST, consisted of Sung-Min Choi, Professor of Nuclear and Quantum Engineering Department, and Ji-Hwan Lee, a doctoral student in the Department, published a paper on the “thermal fluctuation and elasticity of lipid vesicles interacting with pore-forming peptides.” The paper was carried by Physical Review Letters, an internationally renowned peer-review journal on physics on July 16, 2010. Cell membranes, which consist of lipid bilayers, play important roles in cells as barriers to maintain concentrations and matrices to host membrane proteins. During cellular processes such as cell fission and fusion, the cell membranes undergo various morphological changes governed by the interplay between protein and lipid membranes. There have been many theoretical and experimental approaches to understand cellular processes driven by protein-lipid membrane interactions. However, it is not fully established how the membrane elastic properties, which play an important role in membrane deformation, are affected by the protein-membrane interactions. Antimicrobial peptides are one of the most common examples of proteins that modify membrane morphology. While the pore-forming mechanisms of antimicrobial peptides in lipid bilayers have been widely investigated, there have been only a few attempts to understand the mechanisms in terms of membrane elastic properties. In particular, the effects of pore formation on the membrane fluctuation and elastic properties, which provide key information to understand the mechanism of antimicrobial peptide activity, have not been reported yet. The research team reports the thermal fluctuation and elasticity of lipid vesicles interacting with pore-forming peptides, which were measured by neutron spin-echo spectroscopy. The results of this study are expected to pay an important role in understanding the elastic behavior and morphological changes of cell membranes induced by protein-membrane interactions, and may provide new insights for developing new theoretical models for membrane fluctuations which include the membrane mediated interaction between protein patches. (a) (b) Figure (a) Schematics for bound melittin and pores in lipid bilayers (b) P NMR signal ratio (with/without Mn2+) of DOPC LUV-melittin vs P/L at 30˚C. The dashed line is a guide for eyes.
2010.07.23
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Professor Eun-Seong Kim and his research staff observed the phenomena of hysteresis and relaxation dynamics from supersolid Helium
Professor Eun-Seong Kim and his research staff observed the phenomena of hysteresis and relaxation dynamics from supersolid Helium. Their research paper was published in Nature Physics for the issue of April 2010. If we take Helium 4 and cool it down at temperatures below 2.176 Kelivin, liquid helium 4 undergoes a phase transition and becomes superfluid with a zero viscosity. The superfluidity was observed in solid helium through an experiment performed by researchers of Pennsylvania State University in 2004. One of the researchers then was Professor Eun-Seong Kim in the Department of Physics, KAIST. Professor Kim and his research staff, Hyung-Soon Choi, Ph.D., recently published their research results in Nature Physics (April 2010), a highly esteemed journal in the field, on the phenomena of hysteresis and relaxation dynamics observed in supersolid Helium. For the paper, please download the attached .pdf file. Nature Physics link: http://www.nature.com
2010.04.13
View 13340
New drug targeting method for microbial pathogens developed using in silico cell
A ripple effect is expected on the new antibacterial discovery using “in silico” cells Featured as a journal cover paper of Molecular BioSystems A research team of Distinguished Professor Sang Yup Lee at KAIST recently constructed an in silico cell of a microbial pathogen that is resistant to antibiotics and developed a new drug targeting method that could effectively disrupt the pathogen"s growth using the in silico cell. Hyun Uk Kim, a graduate research assistant at the Department of Chemical and Biomolecular Engineering, KAIST, conducted this study as a part of his thesis research, and the study was featured as a journal cover paper in the February issue of Molecular BioSystems this year, published by The Royal Society of Chemistry based in Europe. It was relatively easy to treat infectious microbes using antibiotics in the past. However, the overdose of antibiotics has caused pathogens to increase their resistance to various antibiotics, and it has become more difficult to cure infectious diseases these days. A representative microbial pathogen is Acinetobacter baumannaii. Originally isolated from soils and water, this microorganism did not have resistance to antibiotics, and hence it was easy to eradicate them if infected. However, within a decade, this miroorganism has transformed into a dreadful super-bacterium resistant to antibiotics and caused many casualties among the U.S. and French soldiers who were injured from the recent Iraqi war and infected with Acinetobacter baumannaii. Professor Lee’s group constructed an in silico cell of this A. baumannii by computationally collecting, integrating, and analyzing the biological information of the bacterium, scattered over various databases and literatures, in order to study this organism"s genomic features and system-wide metabolic characteristics. Furthermore, they employed this in silico cell for integrative approaches, including several network analysis and analysis of essential reactions and metabolites, to predict drug targets that effectively disrupt the pathogen"s growth. Final drug targets are the ones that selectively kill pathogens without harming human body. Here, essential reactions refer to enzymatic reactions required for normal metabolic functioning in organisms, while essential metabolites indicate chemical compounds required in the metabolism for proper functioning, and their removal brings about the effect of simultaneously disrupting their associated enzymes that interact with them. This study attempted to predict highly reliable drug targets by systematically scanning biological components, including metabolic genes, enzymatic reactions, that constitute an in silico cell in a short period of time. This research achievement is highly regarded as it, for the first time, systematically scanned essential metabolites for the effective drug targets using the concept of systems biology, and paved the way for a new antibacterial discovery. This study is also expected to contribute to elucidating the infectious mechanism caused by pathogens. "Although tons of genomic information is poured in at this moment, application research that efficiently converts this preliminary information into actually useful information is still lagged behind. In this regard, this study is meaningful in that medically useful information is generated from the genomic information of Acinetobacter baumannii," says Professor Lee. "In particular, development of this organism"s in silico cell allows generation of new knowledge regarding essential genes and enzymatic reactions under specific conditions," he added. This study was supported by the Korean Systems Biology Project of the Ministry of Education, Science and Technology, and the patent for the development of in silico cells of microbial pathogens and drug targeting methods has been filed. [Picture 1 Cells in silico] [Picture 2 A process of generating drug targets without harming human body while effectively disrupting the growth of a pathogen, after predicting metabolites from in silico cells]
2010.04.05
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Photonic crystals allow the fabrication of miniaturized spectrometers
By Courtesy of Nanowerk Photonic crystals allow the fabrication of miniaturized spectrometers (Nanowerk Spotlight) Spectrometers are used in materials analysis by measuring the absorption of light by a surface or chemical substance. These instruments measure properties of light over a specific portion of the electromagnetic spectrum. In conventional spectrometers, a diffraction grating splits the light source into several beams with different propagation directions according to the wavelength of the light. Thus, to achieve sufficient spatial separation for intensity measurements at a small slit, a long light path – i.e., a large instrument – is required. However, for lab-on-a-chip or microTAS (total analysis system) applications, the spectrometer must be integrated into a sub-centimeter scale device to produce a stand-alone platform. To achieve this, researchers at the Korea Advanced Institute of Science and Technology (KAIST) propose a new paradigm in which the spectrometer is based on an array of photonic crystals with different bandgaps. "Because photonic crystals refelct light of different wavelengths selectively depending on their bandgaps, we can generate reflected light spanning the entire wavelength range for analysis at different spatial positions using patterned photonic crystals," Seung-Man Yang, Director of the National Creative Research Initiative Center for Intergrated Optofluidic Systems and Professor of the Department of Chemical & Biomolecular Engineering at KAIST, tells Nanowerk. "Therefore, when the light source impinges on the patterned photonic crytals, we can construct the spectrum using the reflection intensity profile from the constituent photonic crystals." Photonic crystals – also known as photonic band gap material – are similar to semiconductors, only that the electrons are replaced by photons (i.e. light). By creating periodic structures out of materials with contrast in their dielectric constants, it becomes possible to guide the flow of light through the photonic crystals in a way similar to how electrons are directed through doped regions of semiconductors. The photonic band gap (that forbids propagation of a certain frequency range of light) gives rise to distinct optical phenomena and enables one to control light with amazing facility and produce effects that are impossible with conventional optics. To demonstrate this new concept based on patterned photonic crystals, Yang and his group used non-close-packed colloidal crystals of silica particles dispersed in photocurable resin. Due to the repulsive interparticle potential, monodisperse silica particles spontaneously crystallize into non-close-packed face-centered cubic (fcc) structures at volume fractions above 0.1. Therefore, the particle volume fraction determines both the lattice constant and the bandgap position. a) Optical image of an ETPTA film containing porous photonic crystal stripe patterns with 20 different bandgaps. b) Reflectance spectra from the 20 strips. c) Optical microscope image of the middle region with the parallel stripe pattern (denoted as white-dotted box in a). d) Cross-sectional SEM images of first, sixth, eleventh and seventeenth strips. The scale bars in a, c and d are 1 cm, 2mm and 2 µm, respectively. (reprinted with permission from Wiley-VCH Verlag) Reporting their findings in a recent issue of Advanced Materials ("Integration of Colloidal Photonic Crystals toward Miniaturized Spectrometers"), the KAIST team has demonstrated the integration of colloidal photonic crystals with 20 different bandgaps into freestanding films (prepared by soft lithography), and their application as a spectrometer. Yang explains that the team was able to precisely control the photonic bandgap by varying the particle size and volume fration. "The prepared colloidal composite structures showed high physical rigidity and chemical resistivity" he says. "The composite structure is suitable for spectroscopic use due to the small full widths at half maximum (FWHMs) of the reflectance spectra, which mean that there is little overlap of the reflectance spectra of neighboring photonic crystal strips." "On the other hand" says Yang, "porous photonic crystals showed large FWHMs and high reflectivities, which should prove useful in many practical photonic applications that require high optical performance and physical rigidity as well as simple and inexpensive preparation." In addition to fabricating miniaturized spectrometers, which can for instance be integrated into small lab-on-a-chip devices, these integrated photonic crystals can be potentially used for tunable band reflection mirrors, optical switches, and tunable lasing cavities. Moreover, patterned photonic crystals with RGB colors are well-suited for use in reflection-mode microdisplay devices. Yang points out that, although the spectrometric resolution can be reduced by employing the smaller bandgap interval and photonic bandwidth, there is a limitation. "Now, we are studying photonic crystals with continuous modulation of bandgap position. We expect that the photonic crystals can reduce the resolution to 0.01 nm." By Michael Berger. Copyright 2010 Nanowerk
2010.03.17
View 14788
A Breakthrough for Cardiac Monitoring: Portable Smart Patch Makes It Possible for Real-time Observation of Heart Movement
Newly invented device makes the monitoring easier and convenient. Professor Hoi-Jun Yoo of KAIST, Department of Electrical Engineering, said that his research team has invented a smart patch for cardiac monitoring, the first of its kind in the world. Adhesive and can be applied directly to chest in human body, the patch is embedded with a built-in high performance semiconductor integrated circuit (IC), called Healthcare IC, and with twenty five electrodes formed on the patch’s surface. The 25-electrodes, with a capability of creating various configurations, can detect cardiac contractions and relaxations and collect electrocardiogram (ECG) signals. The Healthcare IC monitors ECG signals and sends the information to a portable data terminal like mobile phones, making it possible for a convenient, easy check up on cardiac observations. The key technologies used for the patch are the Healthcare IC that measures cardiovascular impedance and ECG signals, and the electronic circuit board made of four layers of fabric, between which electrodes, wireless antenna, circuit board, and flexible battery are installed. With the P-FCB (Planar Fashionable Circuit Board) technology, the research team explained, electrodes and a circuit board are directly stacked into the fabric. Additionally, the Healthcare IC (size: 5mm x 5mm), which has components of electrode control unit, ECG and cardiovascular resistance detection unit, data compression unit, Static Random Access Memory (SRAM), and wireless transmitter receiver, is attached on the fabric. The Healthcare IC is operated by an ultra-low electrical power. Like a medicated patch commonly used to relieve arthritis pains, the surface of smart patch is adhesive so that people can carry it around without much hassle. A finished product will be 15cm x 15 cm in size and 1mm high in thickness. The Healthcare IC can measure cardiovascular impedance variances with less than 0.81% distortion in 16 different configurations through differential current injectors and reconfigurable high sensitivity detection circuitry. “The patch will be ideal for patients who suffer a chronic heart disease and need to receive a continuous care for their condition. Once commercialized, the patch will allow the patients to conduct a self-diagnosis at anytime and anywhere,” said Yan Long, a member of the research team. There has been a continuously growing demand worldwide since 2000 for the development of technology that provides a suitable healthcare management to patients with a chronic heart disease (e.g., cardiovascular problems), but most of the technology developed today are only limited to monitoring electrical signals of heart activity. Cardiovascular monitors, commonly used at many of healthcare places nowadays, are too bulky to use and give uncomfortable feelings to patients when applied. Besides, the current monitors are connected to an electrical line for power supply, and they are unable to have a low power communication with an outdoor communication gadget, thus unavailable for wide use. Professor Yoo gave his presentation on this new invention at an international conference, International Solid-State Circuits Conference, held on February 8-10 in San Francisco. The subject of his presentation was “A 3.9mW 25-electorde Reconfigurable Thoracic Impedance/ECG SoC with Body-Channel Transponder.” (Picture 1) Structure of Smart Patch (Picture 2) Smart patch when applied onto human body (Picture 3) Data received from smart patch (Picture 4) Healthcare IC
2010.02.17
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