Nature
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Genetic Cause of ADHD (Attention Deficit Hyperactivity Disorder) Found
The cooperative research team consisting research teams under Professor Kim Eun Joon and Professor Kang Chang Won of the department of Biological Sciences discovered that ADHD arises from the deficiency of GIT1 protein in the brain’s neural synapses.
ADHD (Attention Deficit Hyperactivity Disorder) is found in around 5% of children around the world and is a disorder where the child becomes unable to concentrate, show over the top responses, and display impulsive behavior.
The research team found that the difference between children with ADHD and those without it is one base in the GIT1 gene. The difference of a single base causes the underproduction of this protein, and those children with low levels of the protein had a higher probability to develop ADHD.
In addition, further evidence was provided when the research team conducted mice experiments. Those mice with low levels of GIT1 exhibited impulsive and exaggerated reactions like humans with ADHD, had learning disabilities, and produced abnormal brain waves. And upon injecting these mice with cure for ADHD, the symptoms of ADHD disappeared.
The impulsive behavior of ADHD children disappears as the child enters adulthood and a similar pattern was found in mice. A mice with low levels of GIT1 showed impulsive behaviors when 2 months old, but these behaviors disappeared as it got older to around 7 months old (equivalent to 20~30 years old for humans).
Professor Kim Eun Joon commented that there has to be equilibrium between mechanisms that excite the neurons and mechanisms that calm the neurons, but the lack of GIT1 leads to the decrease in the mechanisms that calm the neurons which causes the impulsive behavior of ADHD patients.
In addition, Professor Kang Chang Won commented that the results of the experiment has been receiving rave reviews and is being seen as the new method in the production of the cure for ADHD.
The result of the experiment was published in the online edition of Nature Medicine magazine.
2011.04.30 View 11733 -
The Irish Times: Gene link identified in ADHD, April 18, 2011
The Irish Times wrote an article on the recent research breakthrough made by a KAIST research team to identify a gene that triggers the syndrome of Attention Deficit Hyperactivity Disorder (ADHD) among children. Given the heightened attention to the syndrome across the world, the research result has received a great deal of attention not only from the academia but also from the media and public.
For the article, please visit http://www.irishtimes.com/newspaper/ireland/2011/0418/1224294910305.html. The research paper was appeared online April 17, 2011 in Nature Medicine, which will be printed in its May 2011 issue. For the paper, please click the link of http://www.nature.com/nm/journal/vaop/ncurrent/full/nm.2330.html.
2011.04.18 View 10581
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Professor Min Beom Ki develops metamaterial with high index of refraction
Korean research team was able to theoretically prove that a metamaterial with high index of refraction does exist and produced it experimentally.
Professor Min Beom Ki, Dr. Choi Moo Han, and Doctorate candidate Lee Seung Hoon was joined by Dr. Kang Kwang Yong’s team from ETRI, KAIST’s Professor Less Yong Hee’s team, and Seoul National University’s Professor Park Nam Kyu’s team. The research was funded by the Basic Research Support Program initiated by the Ministry of Education, Science, and Technology and Korea Research Federation.
The result of the research was published in ‘Nature’ magazine and is one of the few researches carried out by teams composed entirely of Koreans.
Metamaterials are materials that have physical properties beyond those materials’ properties that are found in nature. It is formed not with atoms, but with synthetic atoms which have smaller structures than wavelengths.
The optical and electromagnetic waves’ properties of metamaterials can be altered significantly which has caught the attention of scientists worldwide.
Professor Min Beom Ki’s team independently designed and created a dielectric metamaterial with high polarization and low diamagnetism with an index of refraction of 38.6, highest synthesized index value.
It is expected that the result of the experiment will help develop high resolution imaging system and ultra small, hyper sensitive optical devices.
2011.02.23 View 18473
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New Bio-Clock gene and its function found
The Ministry of Education, Science and Technology announced that a Korean research team has found a new gene responsible for maintaining the bio-clock (twenty-four) and its mechanism.
Twnety-four was led by Professor Choi Joon Ho and Dr. Lee Jong Bin of KAIST (department of Biology) and was a joint operation with Professor Ravi Allada and Dr.Lim Jeong Hoon of Northwestern University (department of neurobiology) and the result was published in ‘Nature’ magazine.
The research team experimented with transformed small fruit flies for 4 years and found that there was an undiscovered gene that deals with the bio rhythm in the brain which they named ‘twenty-four’.
The understanding with genes prior to twenty-four was that these genes regulate biorhythm in the transcription phase (DNA to mRNA). Twenty-four operates in the step after transcription when the ribosome creates proteins. Especially twenty-four has a great effect on the ‘period protein’ which acts as a sub-atomic clock that regulates the rhythm and life of each cell.
The experiment was innovational in that it was able to scientifically prove the function of the protein produced by the gene.
The result is expected to help solve the problems associated with sleep disorders, jetlags, eating rhythms, bio rhythms, etc.
The name twenty-four was the fact that a day, a cycle, is 24 hours long and the gene’s serial numbers CG4857 adds up to twenty four.
2011.02.23 View 13181
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Waking Up Is Hard to Do: Scientists have discovered a new mechanism in the core gears of the circadian clock.
The US News & World Report released an article (Feb. 18, 2011) on KAIST’s research collaboration with Northwestern University in the US to identify a gene that regulates the rhythm of a fruit fly’s circadian clock, which may be applied to explain human’s sleep-wake cycle. The research result was published February 17 in the journal Nature.
For the link of the US News & World Report article, please go to the following link:
http://www.usnews.com/science/articles/2011/02/18/waking-up-is-hard-to-do_print.html
2011.02.21 View 11159
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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 View 10507
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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 View 13127 -
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 13567 -
Prof. Ryoo's Team Discovers Breakthrough Method to Create New Zeolite
A group of scientists led by Prof. Ryong Ryoo of the Department of Chemistry, KAIST, has found a method to direct the growth of zeolite, a crystalline substance that is frequently used as catalyst in the chemical and petrochemical industries, the university authorities said on Thursday (Sept. 10).
Ryoo"s research team successfully created ultrathin nano-sheets, only two nano-meters thick, that are efficiently used as long-life catalysts for hydrocarbon cracking and other petrochemical applications. The breakthrough finding, which is credited with taking acidic zeolite catalysts to the limit in terms of thickness, was published in the latest edition of the peer-review journal, "Nature."
A team from the Polytechnic Univeristy of Valencia, Spain, also contributed to the research.
Zeolites are already widely used in the petrochemical industry, but making the catalysts very thin means that reactant molecules can easily diffuse into the zeolite structure and product molecules can get out quickly. This improves the efficiency of the catalyst and reduces unwanted side reactions that can produce polymeric hydrocarbon "coke" that clogs the zeolite pores and eventually kills the catalytic activity, Prof. Yoo said.
To make the thin sheets, Ryoo and his team used a surfactant as a template to direct the growth of the zeolite structure. The surfactant molecule has a polar "head" group - with two quaternary ammonium groups around which the aluminosilicate zeolite crystal grows - and a long hydrocarbon "tail," which prevents the sheets from aggregating together into larger, three dimensional crystals. When the surfactant is removed, these flakes pile up randomly with gaps in between which further aids diffusion to the catalyst sites.
"Zeolite could be used as a catalyst to convert heavy oil into gasoline. Our new zeolite could provide even more possibilities, such as being used as catalysts for transforming methanol into gasline," Ryoo said.
Prof. Ryoo, a Distinguished Professor of KAIST, has won a variety of academic awards, which included the Top Scientist Award given by the Korean government in 2005 and the 2001 KOSEF Science and Technology Award for his work on the synthesis and crystal structure of mezzoporous silica.
Ryoo obtained his bachelor"s degree from Seoul National University in 1977, master"s from KAIST in 1979, and doctorate from Stanford University in 1985.
In 2006, Ryoo and his research team announced the discovery of a form of zeolite that can catalyze petrochemical reactions much more effectively than previous zeolites. Because of the potential of this to streamline the gasoline refining process, it was greeted as a "magical substance" by the South Korean press.
2009.09.11 View 13223 -
Prof. Choi Unveils Method to Improve Emission Efficiency of OLED
A KAIST research team led by Prof. Kyung-Cheol Choi of the School of Electrical Engineering & Computer Science discovered the surface plasmon-enhanced spontaneous emission based on an organic light-emitting device (OLED), a finding expected to improve OLED"s emission efficiency, KAIST authorities said on Thursday (July 9).
For surface plasmon localization, silver nanoparticles were thermally deposited in a high vacuum on cathode. Since plasmons provide a strong oscillator decay channel, time-resolved photoluninescene (PL) results displayed a 1.75-fold increased emission rate, and continuous wave PL results showed a twofold enhanced intensity.
"The method using surface plasmon represents a new technology to enhance the emission efficiency of OLED. It is expected to greatly contribute to the development of new technologies in OLED and flexible display, as well as securing original technology," Prof. Choi said.
The finding was published in the April issue of Applied Physics Letters and the June 25 issue of Optics Express. It will be also featured as the research highlight of the August issue of Nature Photonics and Virtual Journal of Ultrafast Science.
2009.07.09 View 21623 -
KAIST Research Team Unveils Method to Fabricate Photonic Janus Balls
A research team led by Prof. Seung-Man Yang of the Department of Chemical and Biomolecular Engineering has found a method to fabricate photonic Janus balls with isotropic structural colors.
The finding draws attention since the newly-fabricated photonic balls may prove useful pigments for the realization of e-paper or flexible electronic displays.
The breakthrough was published in the Nov. 3 edition of the science journal "Advanced Materials." The Nov. 6 issue of "Nature" also featured it as one of the research highlights under the title of "Future Pixels."
Prof. Yang"s research team found that tiny marbles, black on one side and colored on the other, can be made by "curing" suspensions of silica particles with an ultraviolet lamp. When an electric field is applied, the marbles line up so that the black sides all face upwards, which suggests they may prove useful pigments for flexible electronic displays.
The researchers suspended a flow of carbon-black particles mixed with silica and a transparent or colored silica flow in a resin that polymerizes under ultraviolet light. They then passed the mixture through a tiny see-through tube. The light solidified the silica and resin as balls with differently colored regions, each about 200 micrometers in diameter.
Over the last decades, the development of industrial platforms to artificially fabricate structural color pigments has been a pressing issue in the research areas of materials science and optics. Prof. Yang, who is also the director of the National Creative Research Initiative Center for Integrated Optofluidic Systems, has led the researches focused on fabrication of functional nano-materials through the process of assembling nano-building blocks into designed patterns.
The "complementary hybridization of optical and fluidic devices for integrated optofluidic systems" research was supported by a grant from the Creative Research Initiative Program of the Ministry of Education, Science & Technology.
2008.11.12 View 15408 -
KAIST Professor Exposes Structural Dynamics of Protein in Solution
-- Dr. Hyot-Cherl Ihee"s 3-Year Research Is Valuable in Pharmaceutical Application
Prof. Hyot-Cherl Ihee and his team at the Department of Chemistry, KAIST, has successfully unveiled the structural dynamics of protein in solution as a result of more than three years" research work.
Nature Methods, a sister publication of the authoritative science magazine Nature, published the treatise, titled "Tracking the structural dynamics of proteins in solution using time-resolved wide-angle X-ray scattering" in its Sept. 22 online edition. The research paper will be carried in the magazine"s printed version in its October edition, according to Dr. Lee who is its correspondence author.
In May 2005, Prof. Ihee successfully photographed the structural dynamics of protein in solid state and his findings were published in the Proceedings of National Academy of Science of the United States. As protein normally exists in human body in solution, not in solid state, he directed his research to developing the technology to capture protein"s dynamics in resolved state.
In July that year, Prof. Ihee succeeded in measuring the structural changes of simple organic molecules in real time. He further developed the technology to uncover the structural dynamics of hemoglobin, myoglobin and cytochrome C.
Prof. Ihee"s research, helped with the Education-Science-Technology Ministry"s Creative Research Promotion Fund, can be applied to new pharmaceutical development projects as well as nanotechnology development, according to KAIST officials.
Prof. Ihee who earned his doctorate at California Institute of Technology in 1994 began teaching at KAIST in 2003. He won the Young Scientist Award given by the Korean government in 2006.
2008.09.22 View 14661