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Professor Won Do Heo on LED Light Technology for Controlling Proteins in Living Cells
With the newly developed LED technology, Professor Won Do Heo at the College of Life Science and Bioengineering, KAIST, was able to suppress cell migration and division when cells are exposed to LED light. This suggests a breakthrough to apply in future cancer cell research. Professor Heo talked about the impact of his research in the following excerpt from a news article: “We are already conducting research on the spread of cancer, as well as brain science in animal models with the Light-Activated Reversible Inhibition by Assembled Trap. I believe this technology will be a breakthrough in investigating cancer treatments and the function of neurons in a complex neural network, which existing technologies have not been able to do.” From EE Times Europe, June 19, 2014 “LED Light Technology Controls Proteins in Living Cells” http://www.ledlighting-eetimes.com/en/led-light-technology-controls-proteins-in-living-cells.html?cmp_id=7&news_id=222909336
2014.06.22
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First Instance of Negative Effects from Terahertz-Range Electromagnetic Waves
Professor Philhan Kim Electromagnetic waves (EM-wave) in the terahertz range were widely regarded as the “dream wavelength” due to its perceived neutrality. Its application was also wider than X-rays. However, KAIST scientists have discovered negative effects from terahertz EM-waves. Professor Philhan Kim of KAIST’s Graduate School of Nanoscience and Technology and Dr. Young-wook Jeong of the Korea Atomic Energy Research Institute (KAERI) observed inflammation of animal skin tissue when exposed to terahertz EM-waves. The results were published in the online edition of Optics Express (May 19, 20104). Terahertz waves range from 0.1 to 10 terahertz and have a longer wavelength than visible or infrared light. Commonly used to see through objects like the X-ray, it was believed that the low energy of terahertz waves did not inflict any harm on the human body. Despite being applied for security checks, next-generation wireless communications, and medical imaging technology, little research has been conducted in proving its safety and impact. Conventional research failed to predict the exact impact of terahertz waves on organic tissues as only artificially cultured cells were used. The research team at KAERI developed a high power terahertz EM-wave generator that can be used on live organisms. A high power generator was necessary in applications such as biosensors and required up to 10 times greater power than currently used telecommunications EM-wave. Simultaneously, a KAIST research team developed a high speed, high resolution video-laser microscope that can distinguish cells within the organism. The experiment exposed 30 minutes of terahertz EM-wave on genetically modified mice and found six times the normal number of inflammation cells in the skin tissue after six hours. It was the first instance where negative side effects of terahertz EM-wave were observed. Professor Kim commented that “the research has set a standard for how we can use the terahertz EM-wave safely” and that “we will use this research to analyze and understand the effects of other EM-waves on organisms.”
2014.06.20
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KAIST Made Great Improvements of Nanogenerator Power Efficiency
The energy efficiency of a piezoelectric nanogenerator developed by KAIST has increased by almost 40 times, one step closer toward the commercialization of flexible energy harvesters that can supply power infinitely to wearable, implantable electronic devices. NANOGENERATORS are innovative self-powered energy harvesters that convert kinetic energy created from vibrational and mechanical sources into electrical power, removing the need of external circuits or batteries for electronic devices. This innovation is vital in realizing sustainable energy generation in isolated, inaccessible, or indoor environments and even in the human body. Nanogenerators, a flexible and lightweight energy harvester on a plastic substrate, can scavenge energy from the extremely tiny movements of natural resources and human body such as wind, water flow, heartbeats, and diaphragm and respiration activities to generate electrical signals. The generators are not only self-powered, flexible devices but also can provide permanent power sources to implantable biomedical devices, including cardiac pacemakers and deep brain stimulators. However, poor energy efficiency and a complex fabrication process have posed challenges to the commercialization of nanogenerators. Keon Jae Lee, Associate Professor of Materials Science and Engineering at KAIST, and his colleagues have recently proposed a solution by developing a robust technique to transfer a high-quality piezoelectric thin film from bulk sapphire substrates to plastic substrates using laser lift-off (LLO). Applying the inorganic-based laser lift-off (LLO) process, the research team produced a large-area PZT thin film nanogenerators on flexible substrates (2cm x 2cm). “We were able to convert a high-output performance of ~250 V from the slight mechanical deformation of a single thin plastic substrate. Such output power is just enough to turn on 100 LED lights,” Keon Jae Lee explained. The self-powered nanogenerators can also work with finger and foot motions. For example, under the irregular and slight bending motions of a human finger, the measured current signals had a high electric power of ~8.7 μA. In addition, the piezoelectric nanogenerator has world-record power conversion efficiency, almost 40 times higher than previously reported similar research results, solving the drawbacks related to the fabrication complexity and low energy efficiency. Lee further commented, “Building on this concept, it is highly expected that tiny mechanical motions, including human body movements of muscle contraction and relaxation, can be readily converted into electrical energy and, furthermore, acted as eternal power sources.” The research team is currently studying a method to build three-dimensional stacking of flexible piezoelectric thin films to enhance output power, as well as conducting a clinical experiment with a flexible nanogenerator. This research result, entitled “Highly-efficient, Flexible Piezoelectric PZT Thin Film Nanogenerator on Plastic Substrates,” was published as the cover article of the April issue of Advanced Materials. (http://onlinelibrary.wiley.com/doi/10.1002/adma.201305659/abstract) YouTube Link: http://www.youtube.com/watch?v=G_Fny7Xb9ig Over 100 LEDs operated by self-powered flexible piezoelectric thin film nanogenerator Flexible PZT thin film nanogenerator using inorganic-based laser lift-off process Photograph of large-area PZT thin film nanogenerator (3.5cm × 3.5cm) on a curved glass tube and 105 commercial LEDs operated by self-powered flexible piezoelectric energy harvester
2014.05.19
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Immune Evasion Mechanism of Hepatitis C Virus Revealed
Professor Ui-Cheol Shin Inhibiting major histocompatibility complex [MHC] class I protein expression, T cell immune response is evaded. The research will be a great help to the development of C hepatitis vaccine. Roughly 1-2% of the population in Korea is known to be infected with Hepatitis C. Most Hepatitis C Virus (HCV) infections progress to a chronic disease and can cause liver cirrhosis or liver cancer, which may lead to death. Unlike Hepatitis type A or B, there is no vaccine for Hepatitis C Virus and therefore avoiding exposure to the virus is the best known method of prevention. However, a team of researchers at KAIST has produced research results, which may contribute significantly to the vaccine development. KAIST Graduate School of Medical Sciences & Engineering’ Professor Ui-Cheol Shin and his team have successfully identified why Hepatitis C Virus does not cause an immune response within the human body. The research results were published in the May edition of The Journal of Gastroenterology, a world-renowned journal in the field of gastroenterology. The immune response occurs to eliminate the virus that has invaded our body. During this process, a major histocompatibility complex [MHC] class I plays a key role in inducing T cell response, which is needed for the elimination of virus-infected cells. When a cell is infected by a virus, a substance called interferon causes the increased expression of major histocompatibility complex class I. T cell recognizes the increased MHC class I and therefore finds the virus-infected cells. However, the effect that Hepatitis C Virus has on major histocompatibility complex class I has not been clearly identified until now. The research team has revealed, using a cell culture for infection systems, that the Hepatitis C Virus suppresses the expression of major histocompatibility complex class I. Also, the mechanism to prove that HCV activates a protein called PKR within the cell to inhibit MHC class I protein expression was identified at a molecular level. In this study, researchers established the hypothesis that regulating PKR protein in the cell can enhance the T cell immune response, which was then proved through experiments. Professor Ui-Cheol Shin said, “There are a lot of new drugs to treat Hepatitis C Virus, while its vaccine has not been developed yet. Revealing the HCV immune evasion mechanism will help stimulate momentum for the HCV vaccine development.” The first author of the journal, Dr. Won-Seok Kang is a graduate from Yonsei College of Medicine. After earning his medical degree, he has continued his training as a ‘doctor-scientist’ at KAIST Graduate School of Medical Sciences & Engineering to study Hepatitis C Virus immune evasion mechanism in this research. Hepatitis C Virus activates PKR-eIF2a pathway, which inhibits the major histocompatibility complex class I, and therefore weakens the T cell activation to the viral activity.
2014.05.19
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Binding Regulatory Mechanism of Protein Biomolecules Revealed
Professor Hak-Sung Kim A research team led by Professor Hak-Sung Kim of Biological Sciences, KAIST, and Dr. Mun-Hyeong Seo, KAIST, has revealed a regulatory mechanism that controls the binding affinity of protein’s biomolecules, which is crucial for the protein to recognize molecules and carry out functions within the body. The research results were published in the April 24th online edition of Nature Communications. The protein, represented by enzyme, antibody, or hormones, specifically recognizes a variety of biomolecules in all organisms and implements signaling or immune response to precisely adjust and maintain important biological processes. The protein binding affinity of biomolecules plays a crucial role in determining the duration of the bond between two molecules, and hence to determine and control the in-vivo function of proteins. The researchers have noted that, during the process of proteins’ recognizing biomolecules, the protein binding affinity of biomolecules is closely linked not only to the size of non-covalent interaction between two molecules, but also to the unique kinetic properties of proteins. To identify the basic mechanism that determines the protein binding affinity of biomolecules, Professor Kim and his research team have made mutation in the allosteric site of protein to create a variety of mutant proteins with the same chemical binding surface, but with the binding affinity vastly differing from 10 to 100 times. The allosteric site of the protein refers to a region which does not directly bind with biomolecules, but crucially influences the biomolecule recognition site. Using real-time analysis at the single-molecule level of unique kinetic properties of the produced mutant proteins, the researchers were able to identify that the protein binding affinity of biomolecules is directly associated with the protein’s specific kinetic characteristics, its structure opening rate. Also, by proving that unique characteristics of the protein can be changed at the allosteric site, instead of protein’s direct binding site with biomolecules, the researchers have demonstrated a new methodology of regulating the in-vivo function of proteins. The researchers expect that these results will contribute greatly to a deeper understanding of protein’s nature that governs various life phenomena and help evaluate the proof of interpreting protein binding affinity of biomolecules from the perspective of protein kinetics. Professor Kim said, “Until now, the protein binding affinity of biomolecules was determined by a direct interaction between two molecules. Our research has identified an important fact that the structure opening rate of proteins also plays a crucial role in determining their binding affinity.” [Picture] A correlation graph of opening rate (kopening) and binding affinity (kd) between protein’s stable, open state and its unstable, partially closed state.
2014.05.02
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An Electron Cloud Distribution Observed by the Scanning Seebeck Microscope
All matters are made of small particles, namely atoms. An atom is composed of a heavy nucleus and cloud-like, extremely light electrons. Korean researchers developed an electron microscopy technique that enables the accurate observation of an electron cloud distribution at room-temperature. The achievement is comparable to the invention of the quantum tunneling microscopy technique developed 33 years ago. Professor Yong-Hyun Kim of the Graduate School of Nanoscience and Technology at KAIST and Dr. Ho-Gi Yeo of the Korea Research Institute of Standards and Science (KRISS) developed the Scanning Seebeck Microscope (SSM). The SSM renders clear images of atoms, as well as an electron cloud distribution. This was achieved by creating a voltage difference via a temperature gradient. The development was introduced in the online edition of Physical Review Letters (April 2014), a prestigious journal published by the American Institute of Physics. The SSM is expected to be economically competitive as it gives high resolution images at an atomic scale even for graphene and semiconductors, both at room temperature. In addition, if the SSM is applied to thermoelectric material research, it will contribute to the development of high-efficiency thermoelectric materials. Through numerous hypotheses and experiments, scientists now believe that there exists an electron cloud surrounding a nucleus. IBM's Scanning Tunneling Microscope (STM) was the first to observe the electron cloud and has remained as the only technique to this day. The developers of IBM microscope, Dr. Gerd Binnig and Dr. Heinrich Rohrer, were awarded the 1986 Nobel Prize in Physics. There still remains a downside to the STM technique, however: it required high precision and extreme low temperature and vibration. The application of voltage also affects the electron cloud, resulting in a distorted image. The KAIST research team adopted a different approach by using the Seebeck effect which refers to the voltage generation due to a temperature gradient between two materials. The team placed an observation sample (graphene) at room temperature (37~57℃) and detected its voltage generation. This technique made it possible to observe an electron cloud at room temperature. Furthermore, the research team investigated the theoretical quantum mechanics behind the electron cloud using the observation gained through the Seebeck effect and also obtained by simulation capability to analyze the experimental results. The research was a joint research project between KAIST Professor Yong-Hyun Kim and KRISS researcher Dr. Ho-Gi Yeo. Eui-Seop Lee, a Ph.D. candidate of KAIST, and KRISS researcher Dr. Sang-Hui Cho also participated. The Ministry of Science, ICT, and Future Planning, the Global Frontier Initiative, and the Disruptive Convergent Technology Development Initiative funded the project in Korea. Picture 1: Schematic Diagram of the Scanning Seebeck Microscope (SSM) Picture 2: Electron cloud distribution observed by SSM at room temperature Picture 3: Professor Yong-Hyun Kim
2014.04.04
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Extreme Tech: Nanowire "impossible to replicate" fingerprints could eliminate fraud, counterfeit goods
Research done by Professor Hyun-Joon Song of Chemistry at KAIST on anti-counterfeit, nanoscale fingerprints generated by randomly distributed nanowires was introduced by Extreme Tech, an online global science and technology news. For the articles, please go to: Extreme Tech, March 25, 2014Nanowire ‘impossible to replicate’ fingerprints could eliminate fraud, counterfeit goods http://www.extremetech.com/extreme/179131-nanowire-impossible-to-replicate-fingerprints-could-eliminate-fraud-counterfeit-goods
2014.03.26
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KAIST Holds Open Lecture For Daejeon Residents
Free of cost for any Korean citizen, the registration for the new course opens on the official website from 5th March KAIST’s Department of Humanities and Social Science is currently operating free humanities and liberal arts classes for Daejeon residents. The theme of the course for this semester is “World and Politics,” which will begin on 13th March and run every Thursday for 6 weeks at KAIST’s International Seminar Room. This course has been organized to introduce the general public to the current political situation with neighboring countries such as China, Japan and North Korea, as well as the characteristics of multinational companies. Top experts in the related fields will give lectures. First, Professor Ha-Yong Jung from Kyunghee University will talk on “American liberalism and democracy”; Professor Gyeong-Mo An from Korea National Defense University on “Kim Jeong-Eun and the Future of North Korea--Is the Collapse of North Korea A Reality?” and Ja-Seon Koo, a visiting professor at Korea National Diplomatic Academy on “The Chinese Communist Party during the Xi Jinping Period.” “With the era of globalization, the political situations in the neighboring countries have both direct and indirect effects on our lives,” said Professor Hyeon-Seok Park who has organized the courses. "These classes will be an opportunity for our citizens to understand and learn about the current affairs in the world.” Anyone can attend the course, and registration is from March 5th to 9th at the official webpage of KAIST’s Humanities and Social Sciences Department (http://hss.kaist.ac.kr). All the courses are free of charge. Contact: Department of Humanities and Social Science Research (Tel. 350-4687, E-mail: baobab@kaist.ac.kr)
2014.03.06
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Seo-Eun Lee, an undergaruate student receives the Best Paper Award from Optical Society of Korea
Seo-Eun Lee, a student studying at KAIST’s Department of Biological Sciences, has won the Best Paper Award from Bio-Photonics Division at the 2014 Optical Society of Korea Winter Conference, held on 19th February at Daejeon Convention Center. Only one outstanding paper per division is given an award among the total of 270 papers, and it is very unusual for an undergraduate student to win the award in the field that is not her major. Lee has studied cell imaging using holography technology since June 2013 under the supervision of Professor Yong-Geun Park from the Department of Physics. The Optical Society of Korea was founded in 1989, and as the largest academy in the field of optics in Korea, it holds academic presentations, seminars and lectures every year.
2014.03.06
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Professor Suk-Bok Chang receives 14th Korea Science Award in the field of Chemistry
Professor Suk-Bok Chang from the Department of Chemistry at KAIST received the “2013 Korea Science Award” in chemistry hosted by the National Research Foundation and the Ministry of Science, ICT, and Future Planning, Republic of Korea. The Korea Science Award is a presidential award of Korea, which was first established in 1987 to recognize research excellence in natural science. Three scientists are selected for the award in every other year. Professor Chang primarily researches the catalyzing mechanism of carbon-hydrogen bonds in organic molecules. He has succeeded in making great progress in the field of organic chemistry especially in developing a new type of transition metal catalytic behavior that can be applied to low-reactivity compounds. Hydrocarbons are abundant in nature, but its unreactive nature in ambient conditions makes it unsuitable as reactant for compound synthesis. In addition, the mechanism behind transition metal catalyzed carbon-hydrogen bond synthesis has not been proven sufficiently. The prediction that fossil fuels will be depleted before the end of the century makes hydrocarbon synthesis an extremely important matter. The need for an effective hydrocarbon synthesis method inspired Professor Chang to pursue research in the transition metal catalysis method and to develop a catalytic system that would allow efficient synthesis even in ambient conditions. Professor Chang has been the lead researcher for the Institute for Basic Science’s “molecule catalysis reaction research team” since December 2012 and has been carrying out this research in KAIST.
2014.01.27
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Mechanism in regulation of cancer-related key enzyme, ATM, for DNA damage and repair revealed
Professor Kwang-Wook Choi A research team led by Professor Kwang-Wook Choi and Dr. Seong-Tae Hong from the Department of Biological Sciences at KAIST has successfully investigated the operational mechanism of the protein Ataxia Telangiectasia Mutated (ATM), an essential protein to the function of a crucial key enzyme that repairs the damaged DNA which stores biometric information. The results were published on December 19th Nature Communications online edition. All organisms, including humans, constantly strive to protect the information within their DNA from damages posed by a number of factors, such as carbonized materials in our daily food intake, radioactive materials such as radon emitting from the cement of buildings or ultraviolet of the sunlight, which could be a trigger for cancer. In order to keep the DNA information safe, the organisms are always carrying out complex and sophisticated DNA repair work, which involves the crucial DNA damage repair protein ATM. Consequently, a faulty ATM leads to higher risks of cancer. Until now, academia predicted that the Translationally Controlled Tumor Protein (TCTP) will play an important role in regulating the function of ATM. However, since most of main research regarding TCTP has only been conducted in cultured cells, it was unable to identify exactly what mechanisms TCTP employs to control ATM. The KAIST research team identified that TCTP can combine with ATM or increase the enzymatic activity of ATM. In addition, Drosophilia, one of the most widely used model organisms for molecular genetics, has been used to identify that TCTP and ATM play a very important role in repairing the DNA damaged by radiation. This information has allowed the researchers to establish TCTP’s essential function in maintaining the DNA information in cell cultures and even in higher organisms, and to provide specific and important clues to the regulation of ATM by TCTP. Professor Kwang-Wook Choi said, “Our research is a good example that basic research using Drosophilia can make important contributions to understanding the process of diseases, such as cancer, and to developing adequate treatment.” The research has been funded by the Ministry of Science, ICT and Future Planning, Republic of Korea, and the National Research Foundation of Korea. Figure 1. When the amount of TCTP protein is reduced, cells of the Drosophila's eye are abnormally deformed by radiation. Scale bars = 200mm Figure 2. When the amount of TCTP protein is reduced, the chromosomes of Drosophilia are easily broken by radiation. Scale bars = 10 mm. Figure 3. When gene expressions of TCTP and ATM are reduced, large defects occur in the normal development of the eye. (Left: normal Drosophilia's eye, right: development-deficient eye) Figure 4. ATM marks the position of the broken DNA, with TCTP helping to facilitate this reaction. DNA (blue line) within the cell nucleus is coiled around the histone protein (green cylinder). When DNA is broken, ATM protein attaches a phosphate group (P). Multiple DNA repair protein recognizes the phosphate as a signal that requires repair and gathers at the site.
2014.01.07
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Professor Yong-Hee Lee of Physics Received the Humboldt Research Award
In recognition of his past accomplishments in research and teaching, Professor Yong-Hee Lee of Physics at KAIST received the Humboldt Research Award in November 2013. The Humboldt Research Award is annually given by the Alexander von Humboldt Foundation to internationally renowned scientists and scholars in the fields of biology, chemistry, computer science, economics, linguistics, management, mathematics, medicine, philosophy, and physics. The winners of the award are offered with 60,000 Euros of research grant as well as an opportunity to undertake prolonged periods of research in collaboration with researchers in Germany.Professor Lee, who may be the first Korean physicist receiving the award, plans to conduct joint research with colleagues at the Technical University of Berlin and University of Würzburg.
2014.01.05
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