OT
-
Interesting research results were published on the use of Twitter.
The number of “followers” on your Twitter account does not necessarily mean that “Your opinions matter much” to other people.
A KAIST graduate researcher, Mi-Young Cha, joined an interesting project that studies the influence of a popular social media, Twitter. Most of Twitter users today consider the number of followers as a measurement of their influence on the social sphere. According to the research paper, however, this connection does not seem to standing together. For details, please click the link below for an article published by the New York Times.
Dr. Cha received all of her post secondary education degrees in Computer Science, including her Ph.D. in 2008, from KAIST. Since 2008 till now, she has been a post doctoral researcher at Max Planck Institute for Software Systems (MPI-SWS) based in Germany.
[New York Times Article, March 19, 2010]
http://www.nytimes.com/external/readwriteweb/2010/03/19/19readwriteweb-the-million-follower-fallacy-audience-size-d-3203.html
2010.04.05 View 14548 -
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 View 17831
-
Prime Minister Lars Løkke Rasmussen of the Kingdom of Denmark visited KAIST on March 11, 2010.
Prime Minister Lars Løkke Rasmussen of the Kingdom of Denmark visited KAIST on March 11, 2010. HUBO, a humanoid robotdeveloped by KAIST, gave a warm welcome to the prime minister and his delegation.
Prime Minister Lars Løkke Rasmussen of Denmark visited Moon-Ji Campus of KAIST on March 11, 2010 and had a chance to meet a humanoid robot, HUBO. Since the first appearance in 2005, HUBO has been continuously developed by KAIST for further refinements.
HUBO welcomed the prime minister and offered him a flower bouquet. They also shook hands and exchanged small talks in Danish, which made the delegation pleasantly surprised.
The Danish delegation had a ride on Online Electric Vehicle (OLEV) and showed a great interest in the technology applied therein.
The prime minister said, “Denmark has a keen interest in green technology, and I was very impressed by OLEV. It is just amazing to see how fast KAIST has developed as an outstanding research university in the world during a short period of time.”
President Lee Myung-bak invited the Danish prime minister to discuss current international developments, including issues involving the Korean Peninsula, and ways to enhance bilateral cooperation in such areas as trade, investment, renewable energy and green growth.
2010.03.17 View 13936
-
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 15048
-
Prof. Lee"s Team Succeeds in Producing Plastics Without Use of Fossil Fuels
A team of scientists led by Prof. Sang-Yup Lee of the Department of Biological Sciences at KAIST have succeeded in producing the polymers used for everyday plastics through bioengineering, rather than through the use of fossil fuel based chemicals, the university authorities said on Tuesday (Nov. 24).
This groundbreaking research, which may now allow for the production of environmentally conscious plastics, has been published in two papers in the journal Biotechnology and Bioengineering.
Polymers are molecules found in everyday life in the form of plastics and rubbers. The team consisted of scientists from KAIST and Korean chemical company LG Chem focused their research on polylactic acid (PLA), a bio-based polymer which holds the key to producing plastics through natural and renewable resources.
"The polyesters and other polymers we use everyday are mostly derived from fossil oils made through the refinery or chemical process," said Lee. "The idea of producing polymers from renewable biomass has attracted much attention due to the increasing concerns of environmental problems and the limited nature of fossil resources. PLA is considered a good alternative to petroleum based plastics as it is both biodegradable and has a low toxicity to humans."
Until now PLA has been produced in a two-step fermentation and chemical process of polymerization, which is both complex and expensive. Now, through the use of a metabolically engineered strain of E.coli, the team has developed a one-stage process which produces polylactic acid and its copolymers through direct fermentation. This makes the renewable production of PLA and lactate-containing copolymers cheaper and more commercially viable.
"By developing a strategy which combines metabolic engineering and enzyme engineering, we"ve developed an efficient bio-based one-step production process for PLA and its copolymers," said Lee. "This means that a developed E. coli strain is now capable of efficiently producing unnatural polymers, through a one-step fermentation process,"
This combined approach of systems-level metabolic engineering and enzyme engineering now allows for the production of polymer and polyester based products through direct microbial fermentation of renewable resources.
"Global warming and other environmental problems are urging us to develop sustainable processes based on renewable resources," concluded Lee. "This new strategy should be generally useful for developing other engineered organisms capable of producing various unnatural polymers by direct fermentation from renewable resources".
2009.11.30 View 15729 -
KAIST, CJ Sign MOU for Joint Research in Fundamental Technologies
KAIST and CJ Corporation, Korea"s leading foodstuff maker, have reached an agreement for an enhanced industry-academy cooperation in the biotechnology area, the university authorities said on Tuesday (Nov. 10).
KAIST President Nam-Pyo Suh signed a memorandum of understanding with Kim Jin-soo, CEO of CJ, at the KAIST campus on Tuesday (Nov. 10).
Under the agreement, KAIST and CJ will cooperate in nurturing elite research manpower and conducting joint researches in fundamental technologies. Specifically, CJ researchers will suggest research subjects linked with doctorate programs to KAIST, and once these subjects are accepted by KAIST, CJ researchers will conduct research under the guidance of KAIST professors to get doctorate degrees. All the costs including research expenses incurred during the program will be provided by CJ.
The agreement also calls for CJ to provide funding for the research subjects it selected among the ones suggested by KAIST"s biotechnology professors.
CJ CEO Jin-Soo Kim said: "Through the joint researches with KAIST which has the highest research capabilities, CJ can strengthen basic research capabilities and secure elite research manpower. We hope that the KAIST-CJ partnership will become a successful model for cooperation between industry and academia."
2009.11.11 View 13191 -
National Green Growth Project, Online Electric Vehicle, Showcased on CNN
KAIST"s green growth technologies were broadcast live on U.S. cable news network CNN from 8 a.m. to 9:30 a.m. Oct. 21.
The program was part of CNN"s week-long series, titled "Eye on South Korea," focusing on how Korea is working to become a brand leader on an international scale and how the nation is recovering from the global economic recession.
During the broadcast, award-winning CNN anchor and correspondent Kristie Lu Stout interviewed KAIST President Nam-Pyo Suh to hear about KAIST-developed two green-growth projects, On-Line Electric Car and Mobile Harbor. KAIST"s humanoid robot Hubo was also showcased.
Live broadcasts of "Eye on South Korea" aired from Oct. 21 through 23.
2009.10.21 View 14811 -
Board Chairman Chung Makes First Visit to Building Named After Him
Moon-Soul Chung, chairman of the KAIST board of trustees, visited the building built with his donation on Monday (Oct. 19) for the first time since he made the deed of gift eight years ago, university authorities said on Monday (Oct. 19).
In 2000, Chung, founder and former CEO of Mirae Corp, manufacturer of semiconductor testing equipment, announced retirement and handed over the presidency of his company to one of his managing directors. One year later in 2001, he donated 30 billion won, then equivalent to $30 million, to KAIST. It was by then the largest amount given by a single donor.
The major part of his donation went to constructing a building for the newly-established Department of Bio and Brain Engineering, and it was named after him. However, Chung did not attend the ground-breaking and dedication ceremonies, saying that he would not enter the building until KAIST achieved a breakthrough technology which can inject a hope to Koreans.
On his first visit to the building, he was briefed on the major research outcomes of the department over the past seven years, which were highlighted by the recent invention of an apparatus for measuring perfusion rate of legs. A KAIST team headed by Prof. Chul-Hee Choi invented a light leakage prevention unit including a light emitting device for radiating light having a certain wavelength onto a living body injected with Indocyanine Green (ICG).
According to Prof. Choi, the invention relates to an apparatus for measuring the perfusion rate of legs. The invention also includes a light leakage prevention housing formed to prevent transmission of external light.
Chung expressing satisfaction with the achievements and encouraged professors, researchers and students working at the Moon-Soul Chung Building.
2009.10.20 View 14977 -
Bae's Design Team Wins Good Design Award
An eco-friendly pot humidifier designed by a KAIST team led by Prof. Sang-Min Bae of the Department of Industrial Design won the G-Mark award at the 2009 Good Design Award, university authorities said on Tuesday (Sept. 29).
The Good Design Award is a Japanese comprehensive design evaluation and commendation system operated by the Japan Industrial Design Promotion Organization (JIDPO). It originated from the Good Design Selection system, known as the "G-Mark System," instituted by the Ministry of International Trade and Industry of Japan in 1957. More than 1,000 companies and designers from 50-odd countries submit about 3,000 entries for consideration for the Good Design Awards each year.
The humidifier controls the indoor humidity by natural vaporization using the tissue ball. The tissue ball is made of honeycomb shaped felt so that it can enhance water absorbing ability with large surface. In the package of the pot, there is a bottle of aroma liquid and people can use it for the fragrances as well as humidification.
The pot, called "Love Pot," was designed for the Nanum (Sharing) Project, a charity activity to establish funds for donations through new products development. International aid organization World Vision, oil company GS Caltex and Prof. Bae"s ID+IM design laboratory have teamed up for the project.
The KAIST team worked for free to design the pot. Profits from the sale of the pots were donated for education programs for low-income households. Among the products made under the Nanum Project was a cross cube MP3 player which won the silver prize at the 2008 International Design Excellence Awards (IDEA). IDEA is one of the world"s top three design awards along with Germany"s International Forum DEsign Awards and the Red Dot Design Awards.
Prof. Bae"s team also won the "Best of the Best" award at Red Dot last November with the "Roly Poly Pot," a planter that tips to the side when the plant is thirsty.
2009.10.01 View 13303 -
Prof. Lee"s Team Pioneers Biotechnological Production of Chemical Using Renewable Materials
A research team led by Prof. Sang-Yup Lee of the Bio and Brain Engineering Department at KAIST has succeeded in engineering the bacterium E. coli to produce the industrial chemical putrescine, university authorities said on Monday (Aug. 31).
Putrescine, a four carbon chain diamine, is an important platform chemical with a wide range of applications for the pharmaceutical, agrochemical and chemical industries. It is currently used to synthesize nylon-4,6, a widely used engineering plastic.
The research result, published in the Biotechnology and Bioengineering journal, proviDrdes a renewable alternative to the traditional process using fossil fuels.
Currently the production of putrescine on an industrial scale relies on chemical synthesis, which requires non-renewable petrochemicals and expensive catalyst systems. This process is highly toxic and flammable with potentially severe repercussions for both the environment and human health.
"For the first time we have developed a metabolically engineered E. coli strain that efficiently produces putrescine," said Professor Lee. "The development of a bio-refinery for chemicals and materials is very important in a world where dependency on fossil fuels is an increasing concern."
The team developed a strain of E.coli capable of producing putrescine through metabolic engineering. This is where a cell"s metabolic and regulatory networks are enhanced in order to increase production of a needed material.
First the team weakened or deleted competing metabolic pathways within the E. coli strain before deleting pathways which cause putrescine degradation. They also amplified the crucial enzyme Spec C, which converts the chemical ornithine into putrescine. Finally the putrescine exporter, which allows excretion of intracellularly made putrescine, was engineered while a global regulator was engineered to further increase the concentration of putrescine. The final result of this process was an engineered E.coli strain which produced 24.2 g of putrescine per litre.
However, as it was believed that putrescine is toxic to microorganisms the team had to study putrescine tolerance in E.coli before it could be engineered to overproduce the chemical to the levels needed for industrial production.
The results revealed that E. coli can tolerate at least 0.5 M of putrescine, which is tenfold higher than the usual concentration in the cell. This level of tolerance was an important surprise as it means that E. coli can be engineered to overproduce putrescine to industrially competitive levels.
"The previously expected toxicity of putrescine may explain why its microbial production has been overlooked," said Lee. "Now a metabolically engineered E. coli strain has been developed which is capable of efficiently producing putrescine using renewable methods to an industrial level. This metabolic engineering framework should be useful for developing metabolically engineered microorganisms for the efficient production of other chemicals from renewable resources," he added.
2009.09.01 View 15327 -
Transparent Antenna for Automobile Developed
A research team led by Prof. Jae-Woo Park of the School of Electrical Engineering & Computer Science, KAIST, developed a transparent antenna for the next-generation automobiles, university authorities said on Monday (Aug. 17).
The development was made possible through joint researches with the Hyundai-Kia Automotive Group; Winncom, a car antenna manufacturer; and a group of researchers led by Han-Ki Kim of the Department of Display Materials Engineering at Kyung Hee University in Seoul.
The transparent antennas were developed in two kinds -- one for the HSDPA (High-Speed Downlink Packet Access), a new protocol for mobile telephone data transmission, and the other for transmitting and receiving radio wave for emergency call.
Using the transparent electrically conductive film formation technology, the transparent antennas are to be mounted on the windshield of a vehicle.
"The development of transparent antenna represents a step forward for the advancement of the next-generation automotive electronic technology," said Seong-woo Kim, a senior researcher at the Hyundai-Kia Group.
2009.08.18 View 14792 -
KAIST Professor Sang-Yup Lee Chair of International Metabolic Engineering Conference Due Next Year
KAIST distinguished professor Sang-Yup Lee was named to chair the 17th Metabolic Engineering Conference which will convene on Jeju Island, Korea, next year, under the theme of "Metabolic Engineering for Green Growth." It was decided at the 16th Biochemical Engineering Conference held in Burlington, Vermont, on July 5-9.
Metabolic Engineering Conference in 2010 will not only involve presentations and discussions about metabolic engineering, but will inaugurate the “World Council on Industrial Biotechnology,” which will bring together global corporations and the world’s experts in industrial biochemical engineering, according to sources at KAIST.
A KAIST official commented, “The fact that the Metabolic Engineering Conference is to be held here [in Korea] proves that Korea is being acknowledged as a key player in this field.”
As the world faces the depletion of fossil fuels and environmental pollution, nations are showing increasing interest in industrial biochemical alternatives, such as microscopic organisms or new chemicals, to solve their problems. In addition, efficient production of biochemical materials and bio-fuels using microbes is deemed vital for the future.
“The Korean government has become a model to other countries thanks to its leadership in carrying out the ‘Green Growth’ policy,” Professor Sang-Yup Lee said. He stated that KAIST is recognized for its research in advanced biochemical material and fuel production methods.
“Green Growth,” a concept first developed by ESCAP, the UN agency working for social and economic cooperation in Asia and the Pacific, aims to achieve sustainable economic growth without destroying the environment.
Ref. Department of Biochemical Engineering, Metabolic and BioMolecular Engineering Lab, KAIST
2009.07.17 View 14310