Engineering
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Production of chemicals without petroleum
Systems metabolic engineering of microorganisms allows efficient production of natural and non-natural chemicals from renewable non-food biomass
In our everyday life, we use gasoline, diesel, plastics, rubbers, and numerous chemicals that are derived from fossil oil through petrochemical refinery processes. However, this is not sustainable due to the limited nature of fossil resources. Furthermore, our world is facing problems associated with climate change and other environmental problems due to the increasing use of fossil resources. One solution to address above problems is the use of renewable non-food biomass for the production of chemicals, fuels and materials through biorefineries. Microorganisms are used as biocatalysts for converting biomass to the products of interest. However, when microorganisms are isolated from nature, their efficiencies of producing our desired chemicals and materials are rather low. Metabolic engineering is thus performed to improve cellular characteristics to desired levels. Over the last decade, much advances have been made in systems biology that allows system-wide characterization of cellular networks, both qualitatively and quantitatively, followed by whole-cell level engineering based on these findings. Furthermore, rapid advances in synthetic biology allow design and synthesis of fine controlled metabolic and gene regulatory circuits. The strategies and methods of systems biology and synthetic biology are rapidly integrated with metabolic engineering, thus resulting in "systems metabolic engineering".
In the paper published online in Nature Chemical Biology on May 17, Professor Sang Yup Lee and his colleagues at the Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea present new general strategies of systems metabolic engineering for developing microorganisms for the production of natural and non-natural chemicals from renewable biomass. They first classified the chemicals to be produced into four categories based on whether they have thus far been identified to exist in nature (natural vs. nonnatural) and whether they can be produced by inherent pathways of microorganisms (inherent, noninherent, or created): natural-inherent, natural-noninherent, non-natural-noninherent, and non-natural-created ones. General strategies for systems metabolic engineering of microorganisms for the production of these chemicals using various tools and methods based on omics, genome-scale metabolic modeling and simulation, evolutionary engineering, synthetic biology are suggested with relevant examples. For the production of non-natural chemicals, strategies for the construction of synthetic metabolic pathways are also suggested. Having collected diverse tools and methods for systems metabolic engineering, authors also suggest how to use them and their possible limitations.
Professor Sang Yup Lee said "It is expected that increasing number of chemicals and materials will be produced through biorefineries. We are now equipped with new strategies for developing microbial strains that can produce our desired products at very high efficiencies, thus allowing cost competitiveness to those produced by petrochemical refineries."
Editor of Nature Chemical Biology, Dr. Catherine Goodman, said "It is exciting to see how quickly science is progressing in this field – ideas that used to be science fiction are taking shape in research labs and biorefineries. The article by Professor Lee and his colleagues not only highlights the most advanced techniques and strategies available, but offers critical advice to progress the field as a whole."
The works of Professor Lee have been supported by the Advanced Biomass Center and Intelligent Synthetic Biology Center of Global Frontier Program from the Korean Ministry of Education, Science and Technology through National Research Foundation.
Contact: Dr. Sang Yup Lee, Distinguished Professor and Dean, KAIST, Daejeon, Korea (leesy@kaist.ac.kr, +82-42-350-3930)
2012.05.23 View 11748 -
Professor Kyung Wook Baek Wins the Best Thesis Award at the 2012 Pan-Pacific Microelectronic Symposium
Prof. Kyung Wook Baek from KAIST"s material science department has won the Best Thesis Award at the 2012 Pan-Pacific Microelectronic Symposium.
The title of this thesis was "Recent Advances in Anisotropic Conductive Adhesives Technology : Materials and Processes". Prof Baek had the honor of having his thesis be appointed the best thesis of the symposium.
This thesis includes his 15 years of research on ACAs which are a key element of display and semiconductor packaging technology.
Prof. Baek"s research results has been recognized as incredibly innovative in the field of ACAs and ultrasonic connection devices. This thesis has been recognized as setting the foundation for commercialization by professionals from all over the world at the symposium.
Prof. Baek has announced two innovative technologies on ACAs at the symposium.
One is a technology that merges the nanofiber technology with the ATAs. This technology was highly applauded for overcoming the problem of electric connection in micro-pitch display semiconductors, and successfully applying this to electronic packaging materials.
Currently, commercialization process based on the patent is ongoing. It is expected that we will be able to take hold of the entire market once the commercialization succeeds.
The other technology was to improve the liability and overcome the limits of the current flow in ACAs through the use of solder molecules. This is also undergoing commercialization process for use in mobile electronic devices.
Together with this, Prof.Baek has reported an innovative case where the original heat compression process was replaced with a new ultrasonic process. This discovery is deemed to be extremely great due to its implications in replacing all heat compression systems. This too will soon be commercialized
Prof.Baek has played a crucial role in the development of electronic packaging material and processing technology. He has written the largest number of theses in this area, and has proven himself to be the world"s best through winning this award.
2012.05.10 View 9447
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The output of terahertz waves enhanced by KAIST team
KAIST researchers have greatly improved the output of terahertz waves, the blue ocean of the optics world. This technology is expected to be applied to portable X-ray cameras, small bio-diagnostic systems, and in many other devices.
Professor Ki-Hun Jeong"s research team from the Department of Bio and Brain Engineering used optical nano-antenna technology to increase the output of terahertz waves by three times.
Terahertz waves are electromagnetic waves with frequencies between 100GHz to 30THz. They are produced when a femtosecond (10^-15 s) pulse laser is shone on a semiconductor substrate with photoconduction antennas, causing a photocurrent pulse of one picosecond (10^-12 s). Their long wavelengths, in comparison to visible light and infrared rays, give terahertz waves a high penetration power with less energy than X-rays, making them less harmful to humans.
These qualities allow us to see through objects, just as X-rays do, but because terahertz waves absorb certain frequencies, we can detect hidden explosives or drugs, which was not possible with X-rays. We can even identify fake drugs. Furthermore, using the spectral information, we can analyze a material"s innate qualities without chemical processing, making it possible to identify skin diseases without harming the body. However, the output was not sufficient to be used in biosensors and other applications.
Prof. Jeong"s team added optical nano-antennas, made from gold nano-rods, in between the photoconduction antennas and optimized the structure. This resulted in nanoplasmonic resonance in the photoconduction substrate, increasing the degree of integration of the photocurrent pulse and resulting in a three times larger output.
Hence, it is not only possible to see through objects more clearly, but it is also possible to analyze components without a biopsy.
Professor Jeong explained, "This technology, coupled with the miniaturization of terahertz devices, can be applied to endoscopes to detect early epithelial cancer" and that he will focus on creating and commercializing these biosensor systems.
This research was published in the March issue of the international nanotechnology journal ACS Nano and was funded by the Korea Evaluation Institute of Industrial Technology and the National Research Foundation of Korea.
Figure: Mimetic diagram of a THz generator with nano-antennas
2012.04.29 View 11307 -
High-resolution Atomic Imaging of Specimens in Liquid Observed by Transmission Electron Microscopes Using Graphene Liquid Cells
Looking into specimens in liquid at the atomic level to understand nanoscale processes so far regarded as impossible to witnessThe Korea Advanced Institute of Science and Technology (KAIST) announced that a research team from the Department of Materials Science and Engineering has developed a technology that enables scientists and engineers to observe processes occurring in liquid media on the smallest possible scale which is less than a nanometer.
Professor Jeong Yong Lee and Researcher Jong Min Yuk, in collaboration with Professors Paul Alivisatos’s and Alex Zettl’s groups at the University of California, Berkeley, succeeded in making a graphene liquid cell or capsule, confining an ultra-thin liquid film between layers of graphene, for real-time and in situ imagining of nanoscale processes in fluids with atomic-level resolution by a transmission electron microscope (TEM). Their research was published in the April 6, 2012 issue of Science. (http://www.sciencemag.org/content/336/6077/61.abstract)
The graphene liquid cell (GLC) is composed of two sheets of graphene sandwiched to create a sealed chamber where a platinum growth solution is encapsulated in the form of a thin slice. Each graphene layer has a thickness of one carbon atom, the thinnest membrane that has ever been used to fabricate a liquid cell required for TEM.
The research team peered inside the GLC to observe the growth and dynamics of platinum nanocrystals in solution as they coalesced into a larger size, during which the graphene membrane with the encapsulated liquid remained intact. The researchers from KAIST and the UC Berkeley identified important features in the ongoing process of the nanocrystals’ coalescence and their expansion through coalescence to form certain shapes by imaging the phenomena with atomic-level resolution.
Professor Lee said,
“It has now become possible for scientists to observe what is happening in liquids on an atomic level under transmission electron microscopes.”
Researcher Yuk, one of the first authors of the paper, explained his research work.
“This research will promote other fields of study related to materials in a fluid stage including physical, chemical, and biological phenomena at the atomic level and promises numerous applications in the future. Pending further studies on liquid microscopy, the full application of a graphene-liquid-cell (GLC) TEM to biological samples is yet to be confirmed. Nonetheless, the GLC is the most effective technique developed today to sustain the natural state of fluid samples or species suspended in the liquid for a TEM imaging.”
The transmission electron microscope (TEM), first introduced in the 1930s, produces images at a significantly higher resolution than light microscopes, allowing users to examine the smallest level of physical, chemical, and biological phenomena. Observations by TEM with atomic resolution, however, have been limited to solid and/or frozen samples, and thus it has previously been impossible to study the real time fluid dynamics of liquid phases.
TEM imaging is performed in a high vacuum chamber in which a thin slice of the imaged sample is situated, and an electron beam passes through the slice to create an image. In this process, a liquid medium, unlike solid or frozen samples, evaporates, making it difficult to observe under TEM.
Attempts to produce a liquid capsule have thus far been made with electron-transparent membranes of such materials as silicon nitride or silicon oxide; such liquid capsules are relatively thick (tens to one hundred nanometers), however, resulting in poor electron transmittance with a reduced resolution of only a few nanometers. Silicon nitride is 25 nanometers thick, whereas graphene is only 0.34 nanometers.
Graphene, most commonly found in bulk graphite, is the thinnest material made out of carbon atoms. It has unique properties such as mechanical tensile strength, high flexibility, impermeability to small molecules, and high electrical conductivity. Graphene is an excellent material to hold micro- and nanoscopic objects for observation in a transmission electron microscope by minimizing scattering of the electron beam that irradiates a liquid sample while reducing charging and heating effects.
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Figure 1. Schematic illustration of graphene liquid cells. Sandwiched two sheets of graphene encapsulate a platinum growth solution.
Figure 2. In-situ TEM observation of nanocrystal growth and shape evolution. TEM images of platinum nanocrystal coalescence and their faceting in the growth solution.
2012.04.23 View 11406 -
Paving the Way to Next Generation Display
A new type of LCD that does not require polymer orientation films has been developed by researchers within the country. This technology will enable the creation of thiner and higher definition display.
Prof. Hee Tae Jung form KAIST’s biochemical engineering department led the research and Hyun Soo Jung, Hwan Jin Jeon doctoral students (1st co-authors), Doctor Yun Ho Kim from Korea Chemistry Research Center, and Prof. Shin Woong Kang from Jeon Buk University ( co-author) have participated in this research. This research has been funded by the WCU program and middle-grade researcher support program. The results of the research has been published as the online update of ‘‘Nature Asia Materials(NPG Asia Materials)” which is a sister magazine of the world renowned academic magazine ‘Nature’.
The flat display industry is the core industry leading the 21st century’s IT industry. The LCD is the main area of research. Korea is the leader of this industry, holding more than 50% of the world market. Many technologies are combined to make the electro-optic devices of the LCD function. The most important technology, which determines the indicating element’s quality and function is the technology to align the liquid crystals in one direction.
Currently, all LCD products are created by mechanically cutting into the surface of the polymer film and orienting the liquid crystal material along these cuts. However, the creation of polymer orientation films cost much time and money, and the high temperature processes necessary to stabilize the polymers does not allow for the free selection of circuit boards, and thus does not allow for the use in flexible display.
Prof. Hee Tae Jung devised a method to orient liquid display without the use of a polymer film using ITOs. Prof. Jung’s base technology has been tested on ITOs to maintain the necessary transparency and conductivity after forming a pattern with high decomposition rates and slenderness ratios.
The technology developed by the research team can horizontally or vertically align the transparent conductors without the use of polymer orientation films. Thus, the manufacturing processes have become much shortened and the LCDs can be made in much thinner from a few micrometers to a few centimeters. Also, it has a lower functioning voltage and faster response speed, showing the prospects of a high definition ultra-fast screen display development. Furthermore, this technology can be used for any type of board, and can be adjusted to a nanometer scale. This enables for its use in LCD based flexible or multi-domain modes.
Also, the transparent conductor patterning technology devised by the research team can be used not only for displays, but also for touch panels with highly increased sensitivity.
Prof. Jung said, “It was a long desire of the industry and academia to find a way to replace the polymer orientation film. This new technology does not need any polymer orientation films, and we can still use the original boards used for LCDs. This mean a lot to the industry. Also, this technology will increase the sensitivity of the touch panels for tablet PCs and smart phones. It can be used in many areas of future electronics base technology.”
2012.04.04 View 9864
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Inexpensive Separation Method of Graphene Developed
The problem with commercializing graphene that is synthesized onto metals over a wide area is that it can not be separated from the metal. However, a groundbreaking separation technology which is both cheap and environment friendly has been developed.
Prof. Taek soo Kim and Prof. Byung Jin Cho"s research teams have conducted this research under the support of the Global Frontier program and Researcher Support Program initiated by The Ministry of Education and Science and Korea Research Foundation. The research results have been posted on the online news flash of Nano Letters on februrary 29th. (Thesis title: Direct Measurement of Adhesion Energy of Monolayer Graphene As-Grown on Copper and Its Application to Renewable Transfer Process)
The research has generated exact results on the interfacial adhesive energy of graphene and its surface material for the first time. Through this, the catalyst metal are no longer to be used just once, but will be used for an infinite number of times, thereby being ecofriendly and efficient.
Wide area graphine synthesized onto the catalyst meatal are used in various ways such as for display and for solar cells. There has been much research going on in this field. However, in order to use this wide area graphene, the graphene must be removed from the catalyst metal without damage.
Until now, the metal had been melted away through the use of chemical substances in order to separate the graphene. However, this method has been very problematic. The metal can not be reused, the costs are very high, much harmful wastes were created in the process of melting the metals, and the process was very complicated.
The research teams of Professors Taek Su Kim and Byung Jin Cho measured the interfacial adhesive energy of the synthesized graphene and learned that it could be easily removed.
Also, the mechanically removed graphene was successfully used in creating molecular electronic devices directly. This has thus innovatively shortened the graphene manufacturing process. Also, it has been confirmed that the metalic board can be reused multiple times after the graphene is removed. A new, ecofriendly and cost friendly method of graphene manufacturing has been paved.
Through this discovery, it is expected that graphene will become easier to manufacture and that the period til the commercialization date of graphene will therefore be greatly reduced
Prof. Cho stated " This reserach has much academical meaning significance in that it has successfully defined the surfacial adhesive energy between the graphene and its catalyst material and it should receive much attention in that it solved the largest technical problem involved in the production of graphene.
2012.04.04 View 12643
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KAIST Confers Honorary Degree to CMU President Cohon
By DongJae Lee
The KAIST Herald Staff Reporter
On February 24, Dr. Jared L. Cohon, President of Carnegie Mellon University (CMU), visited KAIST to receive an honorary degree in science and technology and gave a lecture to the university’s students. Dr. Cohon is the eighth president of CMU and has held numerous other public and university positions. During his presidency, CMU has expanded globally and now takes part in joint programs around the world, including those with universities in Korea, Australia, India and Qatar. KAIST and CMU have been collaborating since 2005 in research projects, student and faculty exchange and dual degree programs. Before the 2012 Commencement Ceremony, Dr. Cohon met with The KAIST Herald and other news agencies for an interview.
The interview started with Dr. Cohon giving a brief introduction of CMU. Like KAIST, CMU has a small but special composition and is dedicated to science and technology as well as business and the fine arts. CMU, founded in 1900, is also relatively young by US standards but has nonetheless grown into a world-class university. The power behind this rapid growth can be expressed by four key values: innovation and change, problem-solving, interdisciplinary cooperation, and hard work. The slogan “My heart is in the work” clearly expresses the values of CMU.
One interesting aspect of CMU is its fine arts and business fields. While CMU is dedicated to science and technology, it also has many respected alumni in the aforementioned fields including Andy Warhol, a leading figure in pop art, and Randy Pausch, the author of The Last Lecture. CMU alumni have together won 6 Academy Awards, 22 Emmy Awards, over 100 Tony Awards and 20 Nobel Prizes.
Regarding CMU’s joint projects with KAIST, as well as student and faculty exchanges, Dr. Cohon mentioned joint Ph.D. programs in Civil and Environmental Engineering and Mechanical Engineering and a joint Master’s program in Software Engineering. Currently, the Civil and Environmental Engineering joint Ph.D. program has one participant and the Software Technology Institute joint Master of Software Engineering program has 6 participants.
Dr. Cohon mentioned that receiving an honorary degree in KAIST is a tremendous honor and that he is grateful to be recognized by such a wonderful university like KAIST.
2012.03.23 View 9944 -
Distinguished Professor Sang-Yeop Lee gave keynote speech in '2011 China Bio-Refinery Summit'
Distinguished Professor Sang-Yeop Lee gave keynote speech in ‘2011 China Bio-Refinery Summit’ held in Chang’an, Beijing
Professor Lee gave a lecture on the vitalization strategy of ‘Bio-Refinery’, which is ‘A bio-based chemical industry to replace fossil fuel-based petro chemistry.
Professor Lee, insisted that for the successful construction of ‘Bio-Refinery’, there should be innovation in all value chain of biomass; biomass producer, bio-refinery business, consumer, government, etc. ▲Securement and distribution of Biomass ▲Development of strain and process for fermentation separation to effectively change biomass into chemical substance and fuel ▲Optimization of transportation and marketing.
During this summit, high-ranking government officials in politics and economics, executives of multicultural and Chinese business participated. From Korea, Do-Young Seung of Manager of technology research of GS and Hang-Deok Roh of laboratory chief of SK Chemical participated as panelist.
World Economy Forum, the gathering of leaders and experts in politics, economics, and policy created a ‘Global Agenda Council’ to find solutions on the issue of ‘sustainable growth of environment of the Earth and humanity’. Professor Lee is the chairperson of ‘Emerging Technologies Global Agenda Council (GAC)’ of Word Economy Forum.
Professor Lee, founder of ‘Systems Metabolic Engineering’, has made remarkable achievements world-wide, including a technology that manipulates metabolic circuit of microorganisms to purify various crude-originated chemical substances into environmentally friendly substances.
Currently, he is working on Systems biology research business in Ministry of Education, Science and Technology, Global Frontier Biomass business, Global Frontier Intelligent Bio-system construction and composition, to make progress in metabolic engineering which is essential for the bio-chemical industry.
2012.03.06 View 10895
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Professor Sang-Min Bae appears on EBS Global Theme Travel.
"We want to present "hope" by designing schools and homes for the third-world countries, while considering the culture of the nation.”
Professor Bae and his team went to Ethiopia, Africa, for "Design for Social Donation and Design Research for isolated third-world nations".
Professor Bae commented that, "We have visited for preparatory investigation, experiencing and investigating the life and cultures of the third-world nations in order to design schools and homes."
He continued, "From this visit, we want to develop adequate technology catered for the locals and create a design guideline." He added "We also want to propose a new model using design and technology that contributes to social welfare".
Meanwhile, EBS team accompanied to cover the report and was broadcasted through "EBS Global Theme Travel.
2012.03.06 View 7908
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Annual Future Knowledge Service International Symposium
Knowledge Service Research preparing for the future knowledge based society has been academically publicized.
The First Annual Future Knowledge Service International Symposium was held in COEX Grand Ball Room Hall by KAIST’s department of Knowledge Service Engineering.
Knowledge Service Engineering is a core component to the future knowledge based society and is the convergent result of decision making, recognition sciences, artificial intelligence, IT, and other knowledge management technologies from each of the industries. Therefore Knowledge Service Engineering will innovate the cooperation and communication between humans and machines thereby forming the center point of the development of knowledge society.
The symposium was attended by 9 important figures from domestic and foreign academia, government representative, and key figures from industries. The symposium was based around debates concerning the role of the Knowledge Service Engineering in the future knowledge based society.
The key note speaker was Chairman of Korea Science and Technology Information Research Institute Park Young Suh and the theme of the speech was ‘Change in Information Environment and Knowledge Service’.
Director of National IT Industry Promotion Agency Kang Hyun Gu gave a lecture on the topic of ‘Important Knowledge Service Policies by National IT Industry Promotion Agency’. And from industry experts, Bradley K. Jensen (Manager of Microsoft Industry-Education Cooperation), Lee Kang Yoon (Research Director at IBM), Choi Yoon Shik (Head of Asia Future Human Resource Institute) proposed a direction for research and gave their account on recent trends of knowledge service from the perspective of onsite experience.
Academic experts like Fred D. Davis (Professor at State University of Arkansas), Jussi Kantola (Professor at KAIST), Kim Young Gul (Professor at KAIST Management University), Yoon Wan Chul (Professor at KAIST Knowledge Service Engineering) gave the recent trends in academic research.
The symposium was held in 3 sessions: ▲Policy of Korean Government ▲Academic Research Trend ▲Recent Trend and Application.
More information can be found at http://kss.kaist.ac.kr
2012.01.31 View 8476
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Seeing Inside Cells with Fiber Optics
Professor Jiho Park’s research team was successful in receiving minute optical signals from inside the cell using optical nano fibers.
Through the invention of this technology, we can now look inside cells in high resolution without the use of equipment such as endoscopes that damage cells. We will be able to study the biological phenomena within cells, and thus cure diseases more effectively.
Recently, ultra high resolution microscopes have been used to analyze incubated cells. However, because of the need for a very complex and large system, it had been impossible to monitor cells in the less transparent areas of the body in real time.
The research team created the wire with a semiconductor created with tin oxides to be only 100 nanometers in diameter (1nanometer= 1/1billion meters).
The nanowire is connected to the end of the optical fiber, and the light that comes through the optical fiber is transmitted to particular spots in the cell, and the optical signals from the cell are retrieved back from the cell as well
Together with this, based on the fact that nanowires do not damage cells, the research team covered the end of the wire with a photo reactive material and entered this into the cell. They were able to check that the material reacted to light and entered the cell when they transmitted light
Accordingly, this showed the possibilities of the use of this technology as a method of treatment to effectively transfer the medication into the cells.
Prof. Jiho Park stated that “in this research, we only used cells incubated outside the human body, but soon we will use this technology to stimulate and control cells within the body in a minute scale” as well as that “soon, we will be able to study the biological phenomena inside a cell to study diseases and apply this to cure them more effectively”.
This research result has been published in the online publication of ‘Nature Nanotechnology’ on December 18.
This study was done through the cooperation of various schools. Besides Prof. Jiho Park, Prof. Seungman Yang from the Biochemistry department, and Doctor Chuljoon Huh from KAIST, Prof. Yeonho Choi from Biomedical Science department of Korea University, Professor Peidon Yang and Doctor Ruoxue Yan from UC Berkeley’s chemistry department, and Luke Lee from UC Berkeley’s bioengineering department participated in the project.
2012.01.31 View 9120
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Professor Jang Soon Heung Appointed International Consultant of the Fukushima Nuclear Disaster Task Force
The Japanese government appointed Professor Jang Soon Heung (department of Nuclear and Quantum Engineering) as the International Consultant to the Fukushima Nuclear Disaster Task Force.
Professor Hatamura Yotaro of the Tokyo University is the head of the task force and is tasked with finding out the cause and extent of damage of the disaster and minimize social cost and expansion of damage along with prevent a similar disaster from occurring.
The International Consultants will independently advise and look over the findings of the task force.
The members include: Professor Jang Soon Heung (Professor of KAIST), Richard A. Meserve (Carnegie Research Center Director/Former Chairman of Nuclear Regulatory Commission), Andre-Claude Lacoste (Chairman of French Nuclear Safety Regulatory Commission), and Lars-Eirk Holm (Secretary General of Sweden Health and Welfare).
2012.01.31 View 7912