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Simple Molecular Reagents to Treat Alzheimer’s Disease - Researchers report minimalistic principles for designing small molecules with multiple reactivities against dementia. - Sometimes the most complex problems actually have very simple solutions. A group of South Korean researchers reported an efficient and effective redox-based strategy for incorporating multiple functions into simple molecular reagents against neurodegenerative disorders. The team developed redox-active aromatic molecular reagents with a simple structural composition that can simultaneously target and modulate various pathogenic factors in complex neurodegenerative disorders such as Alzheimer’s disease. Alzheimer’s disease is one of the most prevalent neurodegenerative disorders, affecting one in ten people over the age of 65. Early-onset dementia also increasingly affects younger people. A number of pathogenic elements such as reactive oxygen species, amyloid-beta, and metal ions have been suggested as potential causes of Alzheimer’s disease. Each element itself can lead to Alzheimer’s disease, but interactions between them may also aggravate the patient’s condition or interfere with the appropriate clinical care. For example, when interacting with amyloid-beta, metal ions foster the aggregation and accumulation of amyloid-beta peptides that can induce oxidative stress and toxicity in the brain and lead to neurodegeneration. Because these pathogenic factors of Alzheimer’s disease are intertwined, developing therapeutic agents that are capable of simultaneously regulating metal ion dyshomeostasis, amyloid-beta agglutination, and oxidative stress responses remains a key to halting the progression of the disease. A research team led by Professor Mi Hee Lim from the Department of Chemistry at KAIST demonstrated the feasibility of structure-mechanism-based molecular design for controlling a molecule’s chemical reactivity toward the various pathological factors of Alzheimer’s disease by tuning the redox properties of the molecule. This study, featured as the ‘ACS Editors’ Choice’ in the May 6th issue of the Journal of the American Chemical Society (JACS), was conducted in conjunction with KAIST Professor Mu-Hyun Baik’s group and Professor Joo-Young Lee’s group at the Asan Medical Center. Professor Lim and her collaborators rationally designed and generated 10 compact aromatic molecules presenting a range of redox potentials by adjusting the electronic distribution of the phenyl, phenylene, or pyridyl moiety to impart redox-dependent reactivities against the multiple pathogenic factors in Alzheimer’s disease. During the team’s biochemical and biophysical studies, these designed molecular reagents displayed redox-dependent reactivities against numerous desirable targets that are associated with Alzheimer’s disease such as free radicals, metal-free amyloid-beta, and metal-bound amyloid-beta. Further mechanistic results revealed that the redox properties of these designed molecular reagents were essential for their function. The team demonstrated that these reagents engaged in oxidative reactions with metal-free and metal-bound amyloid-beta and led to chemical modifications. The products of such oxidative transformations were observed to form covalent adducts with amyloid-beta and alter its aggregation. Moreover, the administration of the most promising candidate molecule significantly attenuated the amyloid pathology in the brains of Alzheimer’s disease transgenic mice and improved their cognitive defects. Professor Lim said, “This strategy is straightforward, time-saving, and cost-effective, and its effect is significant. We are excited to help enable the advancement of new therapeutic agents for neurodegenerative disorders, which can improve the lives of so many patients.” This work was supported by the National Research Foundation (NRF) of Korea, the Institute for Basic Science (IBS), and the Asan Institute for Life Sciences. Image credit: Professor Mi Hee Lim, KAIST Image usage restrictions: News organizations may use or redistribute this image, with proper attribution, as part of the news coverage of this paper only. Publication: Kim, M. et al. (2020) ‘Minimalistic Principles for Designing Small Molecules with Multiple Reactivities against Pathological Factors in Dementia.’ Journal of the American Chemical Society (JACS), Volume 142, Issue 18, pp.8183-8193. Available online at https://doi.org/10.1021/jacs.9b13100 Profile: Mi Hee Lim Professor miheelim@kaist.ac.kr http://sites.google.com/site/miheelimlab Lim Laboratory Department of Chemistry KAIST Profile: Mu-Hyun Baik Professor mbaik2805@kaist.ac.kr https://baik-laboratory.com/ Baik Laboratory Department of Chemistry KAIST Profile: Joo-Yong Lee Professor jlee@amc.seoul.kr Asan Institute for Life Sciences Asan Medical Center (END)
2020.05.11 View 12743
Professor Sukyung Park Named Presidential Science and Technology Adviser Professor Sukyung Park from the Department of Mechanical Engineering was appointed as the science and technology adviser to the President Jae-in Moon on May 4. Professor Park, at the age of 47, became the youngest member of the president’s senior aide team at Chong Wa Dae. A Chong Wa Dae spokesman said on May 4 while announcing the appointment, “Professor Park, a talent with a great deal of policymaking participation in science and technology, will contribute to accelerating the government’s push for science and technology innovation, especially in the information and communications technology (ICT) sector.” Professor Park joined KAIST in 2004 as the first female professor of mechanical engineering. She is a biomechanics expert who has conducted extensive research on biometric mechanical behaviors. Professor Park is also a member of the KAIST Board of Trustees. Before that, she served as a senior researcher at the Korea Institute of Machinery and Materials (KIMM) as well as a member of the Presidential Advisory Council on Science and Technology. After graduating from Seoul Science High School as the first ever two-year graduate, Professor Park earned a bachelor and master’s degrees in mechanical engineering at KAIST. She then finished her Ph.D. from the University of Michigan. (END)
2020.05.06 View 11193
Breastfeeding Helps Prevent Mothers from Developing Diabetes after Childbirth A team of South Korean researchers found that lactation can lower the incidence and reduce the risk of maternal postpartum diabetes. The researchers identified that lactation increases the mass and function of pancreatic beta cells through serotonin production. The team suggested that sustained improvements in pancreatic beta cells, which can last for years even after the cessation of lactation, improve mothers’ metabolic health in addition to providing health benefits for infants. Pregnancy imposes a substantial metabolic burden on women through weight gain and increased insulin resistance. Various other factors, including a history of gestational diabetes, maternal age, and obesity, further affect women’s risk of progressing to diabetes after delivery, and the risk of postpartum diabetes increases more in women who have had gestational diabetes and/or repeated deliveries. Diabetes-related complications include damage to blood vessels, which can lead to cardiovascular and cerebrovascular diseases such as heart attack and stroke, and problems with the nerves, eyes, kidneys, and many more. Since diabetes can pose a serious threat to mothers’ metabolic health, the management of maternal metabolic risk factors is important, especially in the peripartum period. Previous epidemiological studies have reported that lactation reduces the risk of postpartum diabetes, but the mechanisms underlying this benefit have remained elusive. The study, published in Science Translational Medicine on April 29, explains the biology underpinning this observation on the beneficial effects of lactation. Professor Hail Kim from the Graduate School of Medical Science and Engineering at KAIST led and jointly conducted the study in conjunction with researchers from the Seoul National University Bundang Hospital (SNUBH) and Chungnam National University (CNU) in Korea, and the University of California, San Francisco (UCSF) in the US. In their study, the team observed that the milk-secreting hormone ‘prolactin’ in lactating mothers not only promotes milk production, but also plays a major role in stimulating insulin-secreting pancreatic beta cells that regulate blood glucose in the body. The researchers also found that ‘serotonin’, known as a chemical that contributes to wellbeing and happiness, is produced in pancreatic beta cells during lactation. Serotonin in pancreatic beta cells act as an antioxidant and reduce oxidative stress, making mothers’ beta cells healthier. Serotonin also induces the proliferation of beta cells, thereby increasing the beta cell mass and helping maintain proper glucose levels. The research team conducted follow-up examinations on a total of 174 postpartum women, 85 lactated and 99 non-lactated, at two months postpartum and annually thereafter for at least three years. The results demonstrated that mothers who had undergone lactation improved pancreatic beta cell mass and function, and showed improved glucose homeostasis with approximately 20mg/dL lower glucose levels, thereby reducing the risk of postpartum diabetes in women. Surprisingly, this beneficial effect was maintained after the cessation of lactation, for more than three years after delivery. Professor Kim said, “We are happy to prove that lactation benefits female metabolic health by improving beta cell mass and function as well as glycemic control.” “Our future studies on the modulation of the molecular serotonergic pathway in accordance with the management of maternal metabolic risk factors may lead to new therapeutics to help prevent mothers from developing metabolic disorders,” he added. This work was supported by grants from the National Research Foundation (NRF) and the National Research Council of Science and Technology (NST) of Korea, the National Institutes of Health (NIH), the Larry L. Hillblom Foundation, and the Health Fellowship Foundation. Image credit: Professor Hail Kim, KAIST Image usage restrictions: News organizations may use or redistribute this image, with proper attribution, as part of news coverage of this paper only. Publication: Moon, J. H et al. (2020) ‘Lactation improves pancreatic β cell mass and function through serotonin production.’ Science Translational Medicine, 12, eaay0455. Available online at https://doi.org/10.1126/scitranslmed.aay0455 Profile: Hail Kim, MD, PhD hailkim@kaist.edu Associate Professor Graduate School of Medical Science and Engineering (GSMSE) Korea Advanced Institute of Science and Technology (KAIST) Profile: Hak Chul Jang, MD, PhD janghak@snu.ac.kr Professor Division of Endocrinology and Metabolism Seoul National University Bundang Hospital (SNUBH) President Korean Diabetes Association Profile: Joon Ho Moon, MD, PhD moonjoonho@gmail.com Clinical Fellow Division of Endocrinology and Metabolism SNUBH Profile: Hyeongseok Kim, MD, PhD hskim85kor@gmail.com Assistant Professor Chungnam National University (CNU) Profile: Professor Michael S. German, MD Michael.German@ucsf.edu Professor Diabetes Center University of California, San Francisco (UCSF) (END)
2020.04.29 View 16133
Long Economic Depressions and Disparities Loom in the Wake of the COVID-19 "Global Cooperation for Managing Data Key to Mitigating the Impacts Around the World" <Full recorded video of the GSI-IF2020> The COVID-19 pandemic will lead to long economic depressions around the entire world. Experts predicted that the prevalent inequities among the countries, regions, and individuals will aggravate the economic crisis. However, crises always come with new opportunities and international cooperation and solidarity will help creating a new normal in the post-coronavirus era. In a very basic but urgent step, global cooperation for managing data is the key to respond to COVID-19 since medicine and healthcare are intertwined with data science, said experts during an online international forum hosted by the Global Strategy Institute at KAIST on April 22. KAIST launched its think-tank, the Global Strategy Institute (GSI), in February. The GSI aims to identify global issues proactively and help make breakthroughs well aligned with solid science-based policies. The inaugural forum of the GSI focused on how the COVID-19 pandemic would impact socio-economic, scientific, and political landscapes, under the theme “Global Cooperation in the Coronavirus Era.” In his opening remarks, KAIST President Sung-Chul Shin stressed that future global governance will be dominated by the power of science and technology. “If we can implement efficient policies together with troubleshooting technology for responding to future crises, we will emerge stronger than before,” he said. President Shin said ‘the Korean model’, which is being recognized as a shining example for dealing with the pandemic, is the result of collaborations combining the creativity of the private sector, the public sector’s strong infrastructure, and the full support of the citizens. He added, “Without the technological prowess coming from the competent R&D power of Korea, we could not achieve these impressive results.” “Creative collaboration among the private and public sectors, along with research universities from around the world, will help shore up global resilience against the epidemic. We should work together to build a world of growing prosperity,” President Shin said. Prime Minister Sye-Kyun Chung, who is in charge of the Central Disaster and Safety Countermeasures Headquarters in Korea, stressed global solidarity in his welcoming remarks, saying that “We need to share information and rely on the strength of our connections, rather than retreating into nationalistic isolation.” Peter Lee, Vice President of the Microsoft Healthcare, pointed out in his welcoming remarks three critical sectors for global cooperation: medicine and healthcare, public health and prevention, and life and the economy. He emphasized the rule of thumb for managing data, saying that data in these fields should be open, standardized, and shared among countries to combat this global pandemic. During a keynote session, Director General of the International Vaccine Institute (IVI) Jerome Kim described the challenges that go along with developing a vaccine. Dr. Kim said that only 7% of vaccine candidates go through the clinical trial stages, and it will take five to 10 years to completely prove a new vaccine’s safety after completing three stages of clinical tests. “It’s very challenging to develop the vaccine for COVID-19 within 12 to 15 months,” said Dr. Kim. He added that 78 out of 115 candidates are currently undergoing clinical trials around the world. There are five groups, including Moderna, Inovio, Jenner Institute, CanSino, and the Beijing Institute of Biological Products, who are doing clinical trials in phases 1 and 2. “Given the fact that COVID-19 is a totally new type of virus, various stakeholders’ participation, such as the National Immunization Technical Advisory Groups, the WHO, and UNICEF, is needed to work together to benefit the entire world,” he pointed out. Professor Edward Yoonjae Choi from the Graduate School of AI at KAIST shared how AI and data sciences are being utilized to interpret the major trends of the epidemic. His group mainly focuses on deep learning to model electronic health records (EHR) for disease predictions. Professor Choi said AI and machine learning would be crucial solutions and collaborative research projects will surely accelerate how quickly we can overcome the pandemic. In addition, Dr. Kijung Shin’s group is interpreting the SIR (Susceptible, Infected, and Recovered) model in Korea to predict the number of infections and when people were infected. However, researchers noticed that they could not see the typical modeling in Korea for predicting the number of infections since the model disregarded the new variable of humans’ efforts to stop the spread the virus. According to research by Professor Steven Whang’s group on social distancing and face mask distribution among vulnerable age groups, people in their 20s, 60s, and 70s followed the social distancing guidelines the most strictly. The research team analyzed the data provided by SK Telecom in the Gangnam district of Seoul. The data provided on people in their 70s, a group that accounted for half of all fatalities, showed that masks were generally well distributed nationwide. Dr. Alexandros Papaspyrids, Tertiary Education Industry Director of the Asia region of Microsoft, said that despite all the disadvantages and problems related to remote education, we shouldn’t expect to return to the days before the COVID-19 any time soon. “We should accept the new normal and explore new opportunities in the new educational environment,” he said. Hongtaek Yong, Deputy Minister at the Office of R&D Policy at the Ministry of Science and ICT presented the Korean government’s disease prevention and response policy and how they tried to mitigate the economic and social impact. He stressed the government’s fast testing, tracing, and openness for successfully flattening the curve, adding that the government used an ICT-based approach in all aspects of their response. From early this year when the first patient was reported, the government aggressively encouraged the biotech industry to develop diagnostic kits and novel therapeutic medications. As a result, five companies were able to produce genetic diagnostic reagents through the emergency approval. More notably, four of them are conducting massive R&D projects sponsored by the government and this is the result of the government’s continuous investment in R&D. Korea is the leader in R&D investment among the OECD countries. According to Yong, the government’s big data project that was launched in 2017 continuously traces the trends of epidemics in Korea. The epidemiological studies based on the paths taken by suspected patients using credit card transaction made the difference in predicting the spread of the coronavirus and implementing countermeasures. The data has been provided to the Korea’s Center for Disease Control (CDC). “In addition to the epidemics, we have so many other pending issues arising from digital and social equities, un-contact services, and job security. We are very open to collaborate and cooperate with other countries to deal with this global crisis,” Yong said. During the subsequent panel discussions, David Dollar, a senior fellow at the Brookings Institution, said, “The global economy in the coronavirus era will not have a rapid V-shaped recovery, but rather will fall into a long depression for at least two years.” He pointed out that if countries practice protectionism like they did during the Great Depression, the recession will be even worse. Hence, he urged the international community, especially developed nations, to avoid protectionism, consider the economic difficulties of developing countries, and provide them with financial support. Co-Director of the Center for Universal Education at the Brookings Institution Rebecca Winthrop raised concerns over the recent shift to online teaching and learning, claiming that insufficient infrastructures in low-income families in developing nations are already causing added educational disparities and provoking the inequity issue around the world. “The ways to provide quality education equally through faster and more effective means should be studied,” she said. Professor Joungho Kim, the director of the KAIST GSI and the forum’s organizer, concluded the event by saying that this forum will be a valuable resource for everyone who is providing assistance to those in need, both during and after the COVID-19 pandemic. (END)
2020.04.22 View 18330
Cyber MOU Signing with Zhejiang University KAIST signed an MOU with Zhejiang University (ZJU) in China on March 25. This MOU signing ceremony took place via video conference due to the outbreak of COVID-19. The collaboration with ZJU had already started with the signing of an MOU for cooperation in technology commercialization last December. Possible cooperation initiatives included facilitating joint start-up businesses, patent portfolios, and technology marketing. With this general agreement signing, it is expected that the two institutes will expand mutual exchanges and collaborations at the institutional level for education and research. President Sung-Chul Shin said, “We will work together to devise measures for the systematic advancement of cooperation in various directions, including education, research, and the commercialization of technologies.” ZJU, a member of the C9 League known as China’s Ivy League, was established in 1897 and is located in the city of Hangzhou. Its population across 37 colleges and schools comprises 54,641 students and 3,741 faculty members. The university was ranked 6th in Asia and 54th in the world in the 2020 QS Rankings. (END)
2020.03.30 View 10933
Highly Efficient and Stable Double Layer Solar Cell Developed Solar cells convert light into energy, but they can be inefficient and vulnerable to the environment, degrading with, ironically, too much light or other factors, including moisture and low temperature. An international research team has developed a new type of solar cell that can both withstand environmental hazards and is 26.7% efficient in power conversion. They published their results on March 26 in Science. The researchers, led by Byungha Shin, a professor from the Department of Materials Science and Engineering at KAIST, focused on developing a new class of light-absorbing material, called a wide bandgap perovskite. The material has a highly effective crystal structure that can process the power needs, but it can become problematic when exposed to environmental hazards, such as moisture. Researchers have made some progress increasing the efficiency of solar cells based on perovskite, but the material has greater potential than what was previously achieved. To achieve better performance, Shin and his team built a double layer solar cell, called tandem, in which two or more light absorbers are stacked together to better utilize solar energy. To use perovskite in these tandem devices, the scientists modified the material’s optical property, which allows it to absorb a wider range of solar energy. Without the adjustment, the material is not as useful in achieving high performing tandem solar cells. The modification of the optical property of perovskite, however, comes with a penalty — the material becomes hugely vulnerable to the environment, in particular, to light. To counteract the wide bandgap perovskite’s delicate nature, the researchers engineered combinations of molecules composing a two-dimensional layer in the perovskite, stabilizing the solar cells. “We developed a high-quality wide bandgap perovskite material and, in combination with silicon solar cells, achieved world-class perovskite-silicon tandem cells,” Shin said. The development was only possible due to the engineering method, in which the mixing ratio of the molecules building the two-dimensional layer are carefully controlled. In this case, the perovskite material not only improved efficiency of the resulting solar cell but also gained durability, retaining 80% of its initial power conversion capability even after 1,000 hours of continuous illumination. This is the first time such a high efficiency has been achieved with a wide bandgap perovskite single layer alone, according to Shin. “Such high-efficiency wide bandgap perovskite is an essential technology for achieving ultra-high efficiency of perovskite-silicon tandem (double layer) solar cells,” Shin said. “The results also show the importance of bandgap matching of upper and lower cells in these tandem solar cells.” The researchers, having stabilized the wide bandgap perovskite material, are now focused on developing even more efficient tandem solar cells that are expected to have more than 30% of power conversion efficiency, something that no one has achieved yet, “Our ultimate goal is to develop ultra-high-efficiency tandem solar cells that contribute to the increase of shared solar energy among all energy sources,” Shin said. “We want to contribute to making the planet healthier.” This work was supported by the National Research Foundation of Korea, the Korea Institute of Energy Technology Evaluation and Planning, the Ministry of Trade Industry and Energy of Korea, and the U.S. Department of Energy. Other contributors include Daehan Kim, Jekyung Kim, Passarut Boonmongkolras, Seong Ryul Pae and Minkyu Kim, all of whom affiliated with the Department of Materials Science and Engineering at KAIST. Other authors include Byron W. Larson, Sean P. Dunfield, Chuanxiao Xiao, Jinhui Tong, Fei Zhang, Joseph J. Berry, Kai Zhu and Dong Hoe Kim, all of who are affiliated with the National Renewable Energy Laboratory in Colorado. Dunfield is also affiliated with the Materials Science and Engineering Program at the University of Colorado; Berry is also affiliated with the Department of Physics and the Renewable and Sustainable Energy Institute at the University of Colorado Boulder; and Kim is also affiliated with the Department of Nanotechnology and Advanced Materials Engineering at Sejong University. Hee Joon Jung and Vinayak Dravid of the Department of Materials Science and Engineering at Northwestern University; Ik Jae Park, Su Geun Ji and Jin Young Kim of the Department of Materials Science and Engineering at Seoul National University; and Seok Beom Kang of the Department of Nanotechnology and Advanced Materials Engineering of Sejong University also contributed. Image credit: Professor Byungha Shin, KAIST Image usage restrictions: News organizations may use or redistribute this image, with proper attribution, as part of news coverage of this paper only. Publication: Kim et al. (2020) “Efficient, stable silicon tandem cells enabled by anion-engineered wide band gap perovskites”. Science. Available online at https://doi.org/10.1126/science.aba3433 Profile: Byungha Shin Professor byungha@kaist.ac.kr http://energymatlab.kaist.ac.kr/ Department of Materials Science and Engineering KAIST Profile: Daehan Kim Ph.D. Candidate zxzx4592@kaist.ac.kr http://energymatlab.kaist.ac.kr/ Department of Materials Science and Engineering KAIST (END)
2020.03.27 View 17529
Ultrathin but Fully Packaged High-Resolution Camera - Biologically inspired ultrathin arrayed camera captures super-resolution images. - The unique structures of biological vision systems in nature inspired scientists to design ultracompact imaging systems. A research group led by Professor Ki-Hun Jeong have made an ultracompact camera that captures high-contrast and high-resolution images. Fully packaged with micro-optical elements such as inverted micro-lenses, multilayered pinhole arrays, and gap spacers on the image sensor, the camera boasts a total track length of 740 μm and a field of view of 73°. Inspired by the eye structures of the paper wasp species Xenos peckii, the research team completely suppressed optical noise between micro-lenses while reducing camera thickness. The camera has successfully demonstrated high-contrast clear array images acquired from tiny micro lenses. To further enhance the image quality of the captured image, the team combined the arrayed images into one image through super-resolution imaging. An insect’s compound eye has superior visual characteristics, such as a wide viewing angle, high motion sensitivity, and a large depth of field while maintaining a small volume of visual structure with a small focal length. Among them, the eyes of Xenos peckii and an endoparasite found on paper wasps have hundreds of photoreceptors in a single lens unlike conventional compound eyes. In particular, the eye structures of an adult Xenos peckii exhibit hundreds of photoreceptors on an individual eyelet and offer engineering inspiration for ultrathin cameras or imaging applications because they have higher visual acuity than other compound eyes. For instance, Xenos peckii’s eye-inspired cameras provide a 50 times higher spatial resolution than those based on arthropod eyes. In addition, the effective image resolution of the Xenos peckii’s eye can be further improved using the image overlaps between neighboring eyelets. This unique structure offers higher visual resolution than other insect eyes. The team achieved high-contrast and super-resolution imaging through a novel arrayed design of micro-optical elements comprising multilayered aperture arrays and inverted micro-lens arrays directly stacked over an image sensor. This optical component was integrated with a complementary metal oxide semiconductor image sensor. This is first demonstration of super-resolution imaging which acquires a single integrated image with high contrast and high resolving power reconstructed from high-contrast array images. It is expected that this ultrathin arrayed camera can be applied for further developing mobile devices, advanced surveillance vehicles, and endoscopes. Professor Jeong said, “This research has led to technological advances in imaging technology. We will continue to strive to make significant impacts on multidisciplinary research projects in the fields of microtechnology and nanotechnology, seeking inspiration from natural photonic structures.” This work was featured in Light Science & Applications last month and was supported by the National Research Foundation (NRF) of and the Ministry of Health and Welfare (MOHW) of Korea. Image credit: Professor Ki-Hun Jeong, KAIST Image usage restrictions: News organizations may use or redistribute this image, with proper attribution, as part of news coverage of this paper only. Publication: Kisoo Kim, Kyung-Won Jang, Jae-Kwan Ryu, and Ki-Hun Jeong. (2020) “Biologically inspired ultrathin arrayed camera for high-contrast and high-resolution imaging”. Light Science & Applications. Volume 9. Article 28. Available online at https://doi.org/10.1038/s41377-020-0261-8 Profile: Ki-Hun Jeong Professor kjeong@kaist.ac.kr http://biophotonics.kaist.ac.kr/ Department of Bio and Brain Engineering KAIST Profile: Kisoo Kim Ph.D. Candidate kisoo.kim1@kaist.ac.kr http://biophotonics.kaist.ac.kr/ Department of Bio and Brain Engineering KAIST (END)
2020.03.23 View 15169
Wearable Strain Sensor Using Light Transmittance Helps Measure Physical Signals Better KAIST researchers have developed a novel wearable strain sensor based on the modulation of optical transmittance of a carbon nanotube (CNT)-embedded elastomer. The sensor is capable of sensitive, stable, and continuous measurement of physical signals. This technology, featured in the March 4th issue of ACS Applied Materials & Interfaces as a front cover article, shows great potential for the detection of subtle human motions and the real-time monitoring of body postures for healthcare applications. A wearable strain sensor must have high sensitivity, flexibility, and stretchability, as well as low cost. Those used especially for health monitoring should also be tied to long-term solid performance, and be environmentally stable. Various stretchable strain sensors based on piezo-resistive and capacitive principles have been developed to meet all these requirements. Conventional piezo-resistive strain sensors using functional nanomaterials, including CNTs as the most common example, have shown high sensitivity and great sensing performance. However, they suffer from poor long-term stability and linearity, as well as considerable signal hysteresis. As an alternative, piezo-capacitive strain sensors with better stability, lower hysteresis, and higher stretchability have been suggested. But due to the fact that piezo-capacitive strain sensors exhibit limited sensitivity and strong electromagnetic interference caused by the conductive objects in the surrounding environment, these conventional stretchable strain sensors are still facing limitations that are yet to be resolved. A KAIST research team led by Professor Inkyu Park from the Department of Mechanical Engineering suggested that an optical-type stretchable strain sensor can be a good alternative to resolve the limitations of conventional piezo-resistive and piezo-capacitive strain sensors, because they have high stability and are less affected by environmental disturbances. The team then introduced an optical wearable strain sensor based on the light transmittance changes of a CNT-embedded elastomer, which further addresses the low sensitivity problem of conventional optical stretchable strain sensors. In order to achieve a large dynamic range for the sensor, Professor Park and his researchers chose Ecoflex as an elastomeric substrate with good mechanical durability, flexibility, and attachability on human skin, and the new optical wearable strain sensor developed by the research group actually shows a wide dynamic range of 0 to 400%. In addition, the researchers propagated the microcracks under tensile strain within the film of multi-walled CNTs embedded in the Ecoflex substrate, changing the optical transmittance of the film. By doing so, it was possible for them to develop a wearable strain sensor having a sensitivity 10 times higher than conventional optical stretchable strain sensors. The proposed sensor has also passed the durability test with excellent results. The sensor’s response after 13,000 sets of cyclic loading was stable without any noticeable drift. This suggests that the sensor response can be used without degradation, even if the sensor is repeatedly used for a long time and in various environmental conditions. Using the developed sensor, the research team could measure the finger bending motion and used it for robot control. They also developed a three-axes sensor array for body posture monitoring. The sensor was able to monitor human motions with small strains such as a pulse near the carotid artery and muscle movement around the mouth during pronunciation. Professor Park said, “In this study, our group developed a new wearable strain sensor platform that overcomes many limitations of previously developed resistive, capacitive, and optical-type stretchable strain sensors. Our sensor could be widely used in a variety of fields including soft robotics, wearable electronics, electronic skin, healthcare, and even entertainment.” This work was supported by the National Research Foundation (NRF) of Korea. Publication: Jimin Gu, Donguk Kwon, Junseong Ahn, and Inkyu Park. (2020) “Wearable Strain sensors Using Light Transmittance Change of Carbon Nanotube-Embedded Elastomers with Microcracks” ACS Applied Materials & Interfaces. Volume 12. Issue 9. Available online at https://doi.org/10.1021/acsami.9b18069 Profile: Inkyu Park Professor inkyu@kaist.ac.kr http://mintlab1.kaist.ac.kr Micro/Nano Transducers Laboratory (MINT Lab) Department of Mechanical Engineering (ME)Korea Advanced Institute of Science and Technology (KAIST) Profile: Jimin Gu Ph.D. Candidate mint9411@kaist.ac.kr http://mintlab1.kaist.ac.kr MINT Lab KAIST ME (END)
2020.03.20 View 15633
Distinguished Alumni Awardees 2019 The KAIST Alumni Association (KAA) announced four recipients of the Distinguished Alumni Awards for the year 2019. The awards ceremony took place during the New Year Alumni Reception on January 18, 2020 in Seoul. The Distinguished Alumni Awards recognize graduates who have achieved outstanding accomplishments in their professional and personal lives, and who have been an inspiration to fellow alumni and students in Korea and around the globe. The four distinguished alumni of the year 2019 are listed below. Myung Joon Kim (School of Computing, M.S., Class of ’78), the President of the Electronics and Telecommunications Research Institute (ETRI), is a renowned expert in software engineering who has served as the president of the Administration Division and ICT Creative Research Laboratory of ETRI. His research and leadership have contributed to fortifying the nation’s IT and electronic industry competitiveness. Dong Ryeol Shin (School of Electrical Engineering, M.S., Class of ’80), the President of Sungkyunkwan University, is a well-versed expert experienced in both academia and industry. He suggested many creative interdisciplinary educational policies and innovative education programs to lead the way in the Fourth Industrial Revolution, and fostered talents who will go on to be the foundation of national development. Dong-Myun Lee (School of Electrical Engineering, M.S., Class of ’85, Ph.D., Class of ‘87), the CTO and the head of the Institute of Convergence Technology in KT Corporation, is a creative and practical research innovator. He raised the nation’s competitiveness by leading the development of the high-speed communication network industry and the global expansion of next-generation technology business. Chang Han Kim (School of Computing, B.S., Class of ’92, M.S., Class of ’97, Ph.D., Class of ’98), the CEO of PUBG Corporation, has contributed greatly to the development of the IT contents industry. He developed PlayerUnknown’s Battlegrounds, a game that has become a global sensation. Since the establishment of the award in 1992, a total of 103 alumni at home and abroad have been honored as recipients, and brought distinction to the university. These recipients are playing major roles in society, and some of the notable awardees include: KAIST President Sung-Chul Shin (2010), Samsung Electronics Vice Chairman Ki-Nam Kim (2012), Nexon Chairman Jung-Ju Kim (2007), and the former Science and Technology Advisor to the President Kong-Joo Lee (2005). The President of KAA and the CEO of Inbody Co Ltd., Ki-Chul Cha, said, “The Distinguished Alumni Awards are honor given to the alumni who contributed to the development of the nation and society, and raised the name of their alma mater.” He added, “We can tell the proud position of KAIST in the global arena just by looking at the accomplishments of the previous awardees.” (END)
2020.01.20 View 8354
Team Geumo Wins Consecutive Victories in K-Cyber Security Challenge < Professor Sang Kil Cha > < Masters Candidate Kangsu Kim and Researcher Corentin Soulet > Team Geumo, led by Professor Sang Kil Cha from the Graduate School of Information Security, won the K-Cyber Security Challenge in the AI-based automatic vulnerability detection division for two consecutive years in 2018 and 2019. The K-Cyber Security Challenge is an inter-machine hacking competition. Participants develop and operate AI-based systems that are capable of independently identifying software vulnerabilities and gaining operating rights through hacking. The K-Cyber Security Challenge, inspired by the US Cyber Grand Challenge launched by the Defense Advanced Research Projects Agency (DARPA), is hosted by the Ministry of Science and ICT and organized by the Korea Internet and Security Agency. Researcher Corentin Soulet of the School of Computing and master’s student Kangsu Kim of the Graduate School of Information Security teamed up for the competition. Professor Cha, who has led the research on software and systems security since his days at Carnegie Mellon University, succeeded in establishing a world-class system using domestic technology. In a recent collaboration with the Cyber Security Research Center, Professor Cha achieved a ten-fold increase in the speed of binary analysis engines, a key component of AI-based hacking systems. For this accomplishment, he received the Best Paper Award at the 2019 Network and Distributed System Security Workshop on Binary Analysis Research (NDSS BAR). Kangsu Kim said, "It is a great honor to win the competition two years in a row. I will continue to work hard and apply my knowledge to serve society.” (END)
2019.12.20 View 8009
Two Professors Receive Awards from the Korea Robotics Society < Professor Jee-Hwan Ryu and Professor Ayoung Kim > The Korea Robotics Society (KROS) conferred awards onto two KAIST professors from the Department of Civil and Environmental Engineering in recognition of their achievements and contributions to the development of the robotics industry in 2019. Professor Jee-Hwan Ryu has been actively engaged in researching the field of teleoperation, and this led him to win the KROS Robotics Innovation (KRI) Award. The KRI Award was newly established in 2019 by the KROS, in order to encourage researchers who have made innovative achievements in robotics. Professor Ryu shared the honor of being the first winner of this award with Professor Jaeheung Park of Seoul National University. Professor Ayoung Kim, from the same department, received the Young Investigator Award presented to emerging robitics researchers under 40 years of age. (END)
2019.12.19 View 7807
New Members of KAST 2020 < Professor Zong-Tae Bae (Left) and Professor Sang Ouk Kim (Right) > Professor Zong-Tae Bae from the School of Management Engineering and Professor Sang Ouk Kim from the Department of Materials Science and Engineering became new fellows of the Korean Academy of Science and Technology (KAST) along with 22 other scientists in Korea. On November 22, KAST announced 24 new members for the year 2020. This includes seven scientists from the field of natural sciences, six from engineering, four from medical sciences, another four from policy research, and three from agriculture and fishery. The new fellows will begin their term from January next year, and their fellowships wll be conferred during the KAST’s New Year Reception to be held on January 14 in Seoul. (END)
2019.12.09 View 10402

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