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The First Demonstration of a Self-powered Cardiac Pacemaker
As the number of pacemakers implanted each year reaches into the millions worldwide, improving the lifespan of pacemaker batteries has been of great concern for developers and manufacturers. Currently, pacemaker batteries last seven years on average, requiring frequent replacements, which may pose patients to a potential risk involved in medical procedures.
A research team from the Korea Advanced Institute of Science and Technology (KAIST), headed by Professor Keon Jae Lee of the Department of Materials Science and Engineering at KAIST and Professor Boyoung Joung, M.D. of the Division of Cardiology at Severance Hospital of Yonsei University, has developed a self-powered artificial cardiac pacemaker that is operated semi-permanently by a flexible piezoelectric nanogenerator.
The artificial cardiac pacemaker is widely acknowledged as medical equipment that is integrated into the human body to regulate the heartbeats through electrical stimulation to contract the cardiac muscles of people who suffer from arrhythmia. However, repeated surgeries to replace pacemaker batteries have exposed elderly patients to health risks such as infections or severe bleeding during operations.
The team’s newly designed flexible piezoelectric nanogenerator directly stimulated a living rat’s heart using electrical energy converted from the small body movements of the rat. This technology could facilitate the use of self-powered flexible energy harvesters, not only prolonging the lifetime of cardiac pacemakers but also realizing real-time heart monitoring.
The research team fabricated high-performance flexible nanogenerators utilizing a bulk single-crystal PMN-PT thin film (iBULe Photonics). The harvested energy reached up to 8.2 V and 0.22 mA by bending and pushing motions, which were high enough values to directly stimulate the rat’s heart.
Professor Keon Jae Lee said:
“For clinical purposes, the current achievement will benefit the development of self-powered cardiac pacemakers as well as prevent heart attacks via the real-time diagnosis of heart arrhythmia. In addition, the flexible piezoelectric nanogenerator could also be utilized as an electrical source for various implantable medical devices.”
This research result was described in the April online issue of Advanced Materials (“Self-Powered Cardiac Pacemaker Enabled by Flexible Single Crystalline PMN-PT Piezoelectric Energy Harvester”: http://onlinelibrary.wiley.com/doi/10.1002/adma.201400562/abstract).
Youtube link: http://www.youtube.com/watch?v=ZWYT2cU_Mog&feature=youtu.be
Picture Caption: A self-powered cardiac pacemaker is enabled by a flexible piezoelectric energy harvester.
2014.06.25 View 15628 -
KAIST doctoral student wins prize at 2014 International Military Science and Technology Fair
Min-Kyu Yoo (far left), a doctoral student in the Department of Materials Science Engineering, KAIST, received a silver prize at the 2014 International Military Science and Technology Fair held from May 29 to June 1, 2014 at KINTEX, Ilsan City, Korea.
Yoo presented a paper on aluminum composite materials that were reinforced by carbon nanotubes. Carbon nanotubes reinforced aluminum composite materials have strong mechanical properties, and some nations have used them to manufacture battle tanks.
Aluminum generates hydrogen in an alkaline solution. Utilizing this property and the galvanic corrosion of carbon nanotubes and aluminums, Yoo developed a hydrogen energy system that is fueled with composite materials of carbon nanotube reinforced aluminum. He produced 5 kW electric power and maintained it 22 days using 10 kg of the composite materials for a proton exchange membrane fuel cell and its auxiliary power system.
Yoo’s research will alleviate the difficulty of transporting fuels during wartime and can be applied to the development of an auxiliary power system for next generation aircrafts and battle tanks.
2014.06.24 View 8014 -
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 View 8670 -
KAIST's Center for Integrated Smart Sensors made a partnership with a Silicon Valley start-up
KAIST's Center for Integrated Smart Sensors (CISS) will implement a joint venture project with Dual Aperture, Inc., a leading digital camera provider based in Palo Alto, California. The two will work on the development of 3-D imaging technology.
CISS, headed by Professor Chong-Min Kyung of Electrical Engineering, KAIST, is dedicated to technological advancement by developing innovative devices, circuits, and smart sensors.
In its press release dated June 18, 2014, Dual Aperture, Inc. stated that “by combining top talents in engineering, the partnership will establish a groundbreaking smart sensor technology accessible on multiple platforms and devices.”
For details, a Fox news article follows below:
Dual Aperture, Inc., June 18, 2014
“Image technology leader and top research institute collaborate engineering resources to create world’s first-ever smart sensor technology”
http://www.fox14tv.com/story/25808022/dual-aperture-announces-joint-venture-with-kaists-center-for-integrated-smart-sensors
2014.06.19 View 8493 -
KAIST studnets win 2014 Creative Vitamin Project Competition
A team of KAIST students have won the grand prize for the “2014 Creative Vitamin Project Competition” held on May 28, 2014 in Seoul. The event was co-hosted by the Ministry of Science, ICT and Future Planning, National Information Society Agency, and Korea IT Convergence Technology Association. The Creative Vitamin Project is the Korean government’s initiative to grow the Korean economy and generate job creation by applying science and technology, information and communications technology in particular, to the existing industry and social issues.
The winners were Hyeong-Min Son, a student in the master’s program in the Department of Civil and Environmental Engineering, KAIST and Su-Yeon Yoo, a Ph.D. student from the Graduate School of Information Security, KAIST.
Son and Yoo proposed a sustainable crop protection system using directional speakers. This technique not only efficiently protects crops from harmful animals, but also effectively guides the animals outside the farmland.
Kwang-Soo Jang, the Director of the National Information Society Agency, said, “This competition provides an opportunity to develop public consensus and interest in the Creative Vitamin Project. We hope that through the participation of all citizens, the project can become an instrument to realizing the creative economy.”
2014.06.18 View 9529 -
Professor Ki Jun Jeong Selected As the Winner of the 'Young Asian Biotechnologist Prize'
Professor Ki Jun Jeong from the Department of Chemical and Biomolecular Engineering, KAIST, has been selected as the winner of this year’s Young Asian Biotechnologist Prize.
Professor Jeong was invited to the 66th Japan Biotechnology and Bioengineering Society Conference scheduled in September 9th-11th, 2014, in Sapporo, Japan, where his award ceremony will be held.
The award is presented to Professor Jeong in recognition of his outstanding research on microbial-based production of antibodies and efficiency improvement.
The Young Asian Biotechnologist Prize is awarded annually by the Japan Biotechnology and Bioengineering Society to the researchers in Asia under the age of 45, who have achieved excellent research results in the field of bioengineering.
2014.06.14 View 8463 -
MOU between KAIST and Sun Medical Center on "Mobile Health Care"
KAIST and Sun Medical Center signed a memorandum of understanding (MOU) in front of 20 attendees including KAIST President Steve Kang and Sun Medical Center Director Seung-Hoon Sun on June 9 at KAIST to expand medical services through medical and electronic telecommunication technology.
The two organizations will cooperate on the research and development of mobile healthcare, systems for the medical industry, remote medical treatment for overseas patients, and working toward improving national healthcare. The two parties will also develop wearable devices and mobile sensors which will become a welcome addition to the global healthcare market.
KAIST President Steve Kang explained, “With Sun Medical Center’s 50 years of experience in medical technology and KAIST’s World University Ranking of 20th in information technology, a new brainchild in the mobile healthcare field will be produced.”
In the meantime, KAIST’s College of Information Science and Technology is making developments in mobile healthcare systems which can accumulate medical information and apply it to medical services by using personal bio-information data. Ambitious new projects are underway, such as the “Dr. M Project“ which launched in March with 28 full-time researchers.
2014.06.14 View 6973 -
A mechanism for how reactive oxygen species cause cell responses studied
A research team led by Professor Kwang-Hyun Cho of the Department of Biology and Brain Engineering, KAIST, and Dr. Gi-Sun Kwon of the Korea Research Institute of Bioscience and Biotechnology succeeded in proving the mechanism behind the determination of cell life in relation to reactive oxygen species.
The results of the venture were published in the June 3rd edition of Science Signaling. The title of the research paper is “MLK3 is part of a feedback mechanism that regulates different cellular responses to reactive oxygen species.”
The research team discovered that the molecular switch that determines the division of apoptosis of a cell was based on MLK3 feedback mechanism. MLK stands for mixed-lineage kinase.
Under sufficient stress, the mechanism instructs the cell to undergo the division but in an overly stressful environment, the mechanism stops the cell division and instead, induces apoptosis. This discovery is expected to be a breakthrough in illnesses related to the concentration of the reactive oxygen species (ROS).
At low concentration of ROS, the protein associated with cell division, ERK (extracellular-signal-regulated kinase), is activated while as the ROS concentration increases, JNK (c-Jun N-terminal protein kinases), responsible for apoptosis, becomes activated. Furthermore, through computer simulation analysis and mathematical modeling, in tandem with molecular cell biology experiments, the MLK3 based feedback mechanism was the fundamental molecular switch that determines the balance between ERK and JNK, and ultimately the cell’s responses.
Professor Cho commented that “the contradicting cell responses to ROS had remained a mystery, but with the system biology, an approach in which information technology and biotechnology converge, such riddles can be resolved. We expect that the proven mechanism will be used to overcome aging or cancer growth as a result of ROS in the near future.”
Picture shows the process of identifying cell responses caused by reactive oxygen species.
2014.06.13 View 8705 -
An Exploratory Study on Smartphone Abuse among College Students
Professor Uichin Lee
Professor Uichin Lee of the Department of Knowledge Service Engineering, KAIST, and his research team developed a system that automatically diagnoses the levels of smartphone addiction based on an analysis of smartphone use records.
Professor Lee investigated the usage patterns of 95 smartphone users (college students) by conducting surveys and interviews and collecting logged data. The research team divided participants into “risk” and “non-risk” groups based on a self-reported rating scale to evaluate their abuse of smartphones. As a result, 36 students were categorized as “high risk” and 59 were categorized as “low risk.”
The researchers collected over 50,000 hours of smartphone use encompassing power levels, screen, battery status, application use, internet use, calling, and texting.
The results showed that the “high risk” group used only 1~2 applications, focusing on mobile messengers (Kakotalk, etc.) and SNS (Facebook, etc.).
In addition, a relationship was found between alarm function and addiction levels. Users who set alarms for Kakaotalk messages and SNS comments used smartphones for an additional 38 minutes per day on average.
Results also showed that “high risk” students were on their smartphones for 4 hours and 13 minutes per day, 46 minutes longer than “low risk” students who used smartphones for 3 hours and 27 minutes. The difference was prevalent during 6 am and noon, and 6pm and midnight. In addition, “high risk” students accessed their smartphones 11.4 times more than “low risk” students.
Based on the collected data, Professor Lee developed an automatic system that distinguished users into “high risk” or “low risk” categories with 80% accuracy. The new system is expected to give an early diagnosis of addiction to smartphone users, thereby allowing for early treatment and intervention before the user becomes addicted.
Professor Lee commented that, "the conventional addiction analysis based on self-analysis surveys did not provide real-time data and were largely inaccurate. The new system overcomes these limitations through data science and personal big data analysis" and that he is "developing an application that monitors smartphone abuse."
Figure 1. Usage amount: overall and application-specific results
Figure 2. Usage frequency: overall and application-specific results
Figure 3. Overall diurnal usage time and frequency
2014.06.05 View 7056 -
Discovery Channel Featured "TransWall" Developed by Professor Woohun Lee
One of the most popular television programs at Discovery Channel in Canada, Daily Planet, a daily science magazine show that delivers a fascinating mix of documentaries and features, aired "TransWall” (http://vimeo.com/70391422) developed by Professor Woohun Lee of Industrial Design at KAIST.
TransWall is a two-sided touchable transparent display with a surface transducer incorporated in the display. It enables users to see, hear, or even touch people standing on the other side of the display, thereby enhancing interactive experiences when playing games or communicating.
TransWall was introduced at the 2014 ACM (Association for Computing Machinery) Conference on Human Factors in Computing Systems (CHI) held in Toronto, Canada, from April 26 to May 1. The Channel learned about the technology at the conference and produced the show on April 30, 2014.
To watch the show, please visit:
http://www.youtube.com/watch?v=5GGP59S7T2k&list=PLXmuftxI6pTXuyjjrGFlcN5YFTKZinDhK.
2014.05.29 View 8731 -
President Steve Kang Received an Honorary Degree from Fairleigh Dickinson University
At its 71st Commencement held on May 20, 2014, Fairleigh Dickinson University (FDU) in Teaneck, NJ, conferred an honorary doctorate (Doctor of Science) on President Steve Kang. FDU is President Kang’s alma mater. He received a bachelor’s degree from FDU in electrical engineering in 1970.
For details, please refer to the press statement released by FDU on May 20, 2014.
Fairleigh Dickinson University holds 71st Commencement on May 20
During the Commencement ceremony, the University will confer honorary degrees on Joyce Carol Oates, Rachel Robinson, and Sung Mo “Steve” Kang (BSEE’70).
http://inside.fdu.edu/prpt/71st_commencement.html
2014.05.25 View 7056 -
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 View 13453