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Diva Sumi Jo to Join the KAIST Faculty
Visiting Distinguished Professor Jo will enrich KAIST’s scholarship and inspire futuristic art and technology research
Soprano Sumi Jo will join the KAIST faculty from the spring 2022 semester. Named as a visiting distinguished professor in the Graduate School of Culture Technology, she will give special leadership lectures. Her tenure will be through September 2024.
Jo joined the appointment ceremony held online at KAIST on October 14 from Portugal and expressed her high expectations for teaching KAIST students from next year. “I am very grateful for this opportunity to meet students at KAIST, the birthplace of advanced science and technology in Korea,” she said.
KAIST President Kwang Hyung Lee, who has stressed the importance of humanities and the arts in convergence studies of science and technology, lauded her joining the faculty as a big asset who will enrich KAIST’s scholarship. “Soprano Sumi Jo rose to stardom on the global music stage with her unrivaled talent and effort. I truly believe her experience and passion will inspire our students to expand their horizon of thought and knowledge,” said President Lee.
Distinguished Professor Jo will also participate in convergence research at the Graduate School of Culture Technology with KAIST professors and many other experts. The Sumi Jo Performing Arts Research Center at the Graduate School of Culture Technology will conduct research on the converging of imaging and audio processing technologies that will enhance virtual artists’ performances. Distinguished Professor Jo explained, “The world is changing so fast. I look forward to working on culture technology research at KAIST that will raise our life quality.”
Professor Juhan Nam from the Graduate School of Culture Technology said, “We look forward to working closely with her and her team to develop research themes that envision futuristic art combined with technology such as the metaverse and non-fungible tokens (NFTs).
Coloratura soprano Jo was born in Seoul and educated at Seoul National University and the Conservatorio Santa Cecilia in Italy. Among her teachers were Carolo Bergonzi and Giasnnelas Borelli. Following her graduation from the Conservatorio Santa Cecilia in 1985, she swept major international competitions in Seoul and Europe. In 1986, she was unanimously awarded the first prize in the Carlo Alberto Cappelli International Competition in Verona which is open only to the first-prize winners of major competitions.
Since her debut in the role of Gilda in Verdi’s Rigolleto in Italy in 1986, she has performed on the world's biggest stages along with noted maestros such as Herbert von Karajan, Georg Solti, Zubin Mehta, and James Levine. Distinguished Professor Jo, one of the most sought-after sopranos in the world, released more than 40 albums.
2021.10.15 View 5782 -
KAIST Entrepreneurial Partnership to Accelerate Startups and Venture Ecosystem
KAIST will launch the KAIST Entrepreneurial Partnership (KEP) program, which connects faculty members who own technology with those who want to launch startup.
The program encourages open innovation startups using strategies tailored to market-client demand requirements. This is also one of efforts to help realize ‘one startup per lab,’ initiated by President Kwang Hyung Lee’s new innovation strategy. KEP also aims to introduce the best technologies developing at KAIST to startups and to raise the success rate of technology commercialization.
The program will match KAIST faculty and student entrepreneur candidates with parties enrolled in the new Entrepreneur in Residence and Entrepreneurial Partner programs. Each team will be given a six-month test period with funding support.
KAIST will invite entrepreneurial experts from both technology and management fields to support the program participants. Around 30 experts with experience in developing new businesses, startups, and investments in large corporations or venture companies will be recruited as entrepreneurial partners. They will offer support for research and business development (R&BD), technology marketing, attracting venture investment from corporations, mergers and acquisitions, and business openings.
A survey showed that KAIST members who are interested in starting a business are experiencing difficulties finding an entrepreneurial expert (72.2%), with the complicated startup approval procedures (33.3%), and their lack of knowledge on entrepreneurship and funding (27.8%). The KEP program hopes to encourage KAIST faculty members and students who have well-developed business ideas and the appropriate technology but lack the capabilities to realize and develop them into a business.
Associate Vice President of Startups Young-Tae Kim said, “We will develop KEP into KAIST’s distinct entrepreneurial support system and produce exemplary outcomes of faculty and student startups. We will spread the startup DNA and lead the building of a virtuous cycle between entrepreneurship and the venture ecosystem.”
2021.10.14 View 6027 -
Industrial Liaison Program to Provide Comprehensive Consultation Services
The ILP’s one-stop solutions target all industrial sectors including conglomerates, small and medium-sized enterprises, venture companies, venture capital (VC) firms, and government-affiliated organizations.
The Industrial Liaison Center at KAIST launched the Industrial Liaison Program (ILP) on September 28, an industry-academic cooperation project to provide comprehensive solutions to industry partners. The Industrial Liaison Center will recruit member companies for this service every year, targeting all industrial sectors including conglomerates, small and medium-sized enterprises, venture companies, venture capital (VC) firms, and government-affiliated organizations.
The program plans to build a one-stop support system that can systematically share and use excellent resource information from KAIST’s research teams, R&D achievements, and infrastructure to provide member companies with much-needed services.
More than 40 KAIST professors with abundant academic-industrial collaboration experience will participate in the program. Experts from various fields with different points of view and experiences will jointly provide solutions to ILP member companies. To actively participate in academic-industrial liaisons and joint consultations, KAIST assigned 10 professors from related fields as program directors.
The program directors will come from four different fields including AI/robots (Professor Alice Oh, School from the School of Computing, Professor Young Jae Jang from the Department of Industrial & Systems Engineering, and Professor Yong-Hwa Park from Department of Mechanical Engineering), bio/medicine (Professor Daesoo Kim from Department of Biological Sciences and Professor YongKeun Park from Department of Physics), materials/electronics (Professor Sang Ouk Kim from the Department of Materials Science and Engineering and Professors Jun-Bo Yoon and Seonghwan Cho from the School of Electrical Engineering), and environment/energy (Professor Hee-Tak Kim from the Department of Biological Sciences and Professor Hoon Sohn from the Department of Civil and Environmental Engineering).
The transdisciplinary board of consulting professors that will lead technology innovation is composed of 30 professors including Professor Min-Soo Kim (School of Computing, AI), Professor Chan Hyuk Kim (Department of Biological Sciences, medicine), Professor Hae-Won Park (Department of Mechanical Engineering, robots), Professor Changho Suh (School of Electrical Engineering, electronics), Professor Haeshin Lee (Department of Chemistry, bio), Professor Il-Doo Kim (Department of Materials Science and Engineering, materials), Professor HyeJin Kim (School of Business Technology and Management), and Professor Byoung Pil Kim (School of Business Technology and Management, technology law)
The Head of the Industrial Liaison Center who is also in charge of the program, Professor Keon Jae Lee, said, “In a science and technology-oriented generation where technological supremacy determines national power, it is indispensable to build a new platform upon which innovative academic-industrial cooperation can be pushed forward in the fields of joint consultation, the development of academic-industrial projects, and the foundation of new industries.
He added, “KAIST professors carry out world-class research in many different fields and faculty members can come together through the ILP to communicate with representatives from industry to improve their corporations’ global competitiveness and further contribute to our nation’s interests by cultivating strong small enterprises
2021.09.30 View 6786 -
Deep Learning Framework to Enable Material Design in Unseen Domain
Researchers propose a deep neural network-based forward design space exploration using active transfer learning and data augmentation
A new study proposed a deep neural network-based forward design approach that enables an efficient search for superior materials far beyond the domain of the initial training set. This approach compensates for the weak predictive power of neural networks on an unseen domain through gradual updates of the neural network with active transfer learning and data augmentation methods.
Professor Seungwha Ryu believes that this study will help address a variety of optimization problems that have an astronomical number of possible design configurations. For the grid composite optimization problem, the proposed framework was able to provide excellent designs close to the global optima, even with the addition of a very small dataset corresponding to less than 0.5% of the initial training data-set size. This study was reported in npj Computational Materials last month.
“We wanted to mitigate the limitation of the neural network, weak predictive power beyond the training set domain for the material or structure design,” said Professor Ryu from the Department of Mechanical Engineering.
Neural network-based generative models have been actively investigated as an inverse design method for finding novel materials in a vast design space. However, the applicability of conventional generative models is limited because they cannot access data outside the range of training sets. Advanced generative models that were devised to overcome this limitation also suffer from weak predictive power for the unseen domain.
Professor Ryu’s team, in collaboration with researchers from Professor Grace Gu’s group at UC Berkeley, devised a design method that simultaneously expands the domain using the strong predictive power of a deep neural network and searches for the optimal design by repetitively performing three key steps.
First, it searches for few candidates with improved properties located close to the training set via genetic algorithms, by mixing superior designs within the training set. Then, it checks to see if the candidates really have improved properties, and expands the training set by duplicating the validated designs via a data augmentation method. Finally, they can expand the reliable prediction domain by updating the neural network with the new superior designs via transfer learning. Because the expansion proceeds along relatively narrow but correct routes toward the optimal design (depicted in the schematic of Fig. 1), the framework enables an efficient search.
As a data-hungry method, a deep neural network model tends to have reliable predictive power only within and near the domain of the training set. When the optimal configuration of materials and structures lies far beyond the initial training set, which frequently is the case, neural network-based design methods suffer from weak predictive power and become inefficient.
Researchers expect that the framework will be applicable for a wide range of optimization problems in other science and engineering disciplines with astronomically large design space, because it provides an efficient way of gradually expanding the reliable prediction domain toward the target design while avoiding the risk of being stuck in local minima. Especially, being a less-data-hungry method, design problems in which data generation is time-consuming and expensive will benefit most from this new framework.
The research team is currently applying the optimization framework for the design task of metamaterial structures, segmented thermoelectric generators, and optimal sensor distributions. “From these sets of on-going studies, we expect to better recognize the pros and cons, and the potential of the suggested algorithm. Ultimately, we want to devise more efficient machine learning-based design approaches,” explained Professor Ryu.This study was funded by the National Research Foundation of Korea and the KAIST Global Singularity Research Project.
-Publication
Yongtae Kim, Youngsoo, Charles Yang, Kundo Park, Grace X. Gu, and Seunghwa Ryu, “Deep learning framework for material design space exploration using active transfer learning and data augmentation,” npj Computational Materials (https://doi.org/10.1038/s41524-021-00609-2)
-Profile
Professor Seunghwa Ryu
Mechanics & Materials Modeling Lab
Department of Mechanical Engineering
KAIST
2021.09.29 View 11460 -
Two Researchers Designated as SUHF Fellows
Professor Taeyun Ku from the Graduate School of Medical Science and Engineering and Professor Hanseul Yang from the Department of Biological Sciences were nominated as 2021 fellows of the Suh Kyungbae Foundation (SUHF).
SUHF selected three young promising scientists from 53 researchers who are less than five years into their careers. A panel of judges comprised of scholars from home and abroad made the final selection based on the candidates’ innovativeness and power to influence. Professor You-Bong Hyun from Seoul National University also won the fellowship.
Professor Ku’s main topic is opto-connectomics. He will study ways to visualize the complex brain network using innovative technology that transforms neurons into optical elements.
Professor Yang will research the possibility of helping patients recover from skin diseases or injuries without scars by studying spiny mouse genes.
SUHF was established by Amorepacific Group Chairman Suh Kyungbae in 2016 with 300 billion KRW of his private funds. Under the vision of ‘contributing to humanity by supporting innovative discoveries of bioscience researchers,’ the foundation supports promising Korean scientists who pioneer new fields of research in biological sciences.
From 2017 to this year, SUHF has selected 20 promising scientists in the field of biological sciences. Selected scientists are provided with up to KRW 500 million each year for five years. The foundation has provided a total of KRW 48.5 billion in research funds to date.
2021.09.15 View 8160 -
MCM Utilized at Residential Treatment Center in Gyeonggi
The Mobile Clinic Module (MCM) developed by the KAIST Action for Respiratory Epidemics was installed at special residential treatment center in Gyeonggi Province on September 13.
The MCM is an isolate negative pressure unit fitted with high-quality medical equipment, developed by Professor Taek-Jin Nam of the Department of Industrial Design under the KAIST New Deal R&D Initiative. This is also a part of the Korean Disease Control Package Development Project from last July.
In January, a ward with four beds for critical care was installed at the Korea Institute for Radiological & Medical Sciences in Seoul for a trial operation, and two mild cases were treated there. It was also implemented as an isolated negative pressure unit in the Daejeon Konyang University Hospital emergency room in June, and has treated 138 cases since.
The special residential treatment center installed in the Gyeonggi Provincial Academy gymnasium, which consists of 28 beds in 14 rooms (double occupancy) and a multipurpose room (for X-rays and treatment), is to remain open through October 10. Unlike existing treatment centers that have quarantined COVID-19 patients for two weeks, the Gyeonggi MCM will act as a self-treatment-associated short-term treatment center. While in self-treatment, patients showing symptoms requiring special attention will be moved to the MCM, followed by short-term hospitalization of 1-3 days for observation before further measures are taken.
Patients can be treated using the MCM’s own treatment capacities, including in-person and oxygen treatment, X-rays, and IVs. There are individual bathrooms in each room, and the pressure, ventilation, and the automatic opening and closing of the entrance can be centrally monitored and controlled. Patients showing symptoms during treatment will be moved to a specially designated hospital for critical care, and will return to the self-treatment center if no further abnormalities are reported.
The Gyeonggi Provincial Medical Center’s Ansung Hospital will take charge of operating the special treatment center. Each day, one or two doctors, three nurses, two nursing assistants, one administrative staff member, two or three disinfection specialists, and a medical imaging engineer will work in three shifts. There will also be about 20 additional specially designated staff members including KAIST researchers, firefighters, and police officers.
The MCM was internationally recognized as an excellent medical facility not only for its functionality, economic feasibility, and utility, but also for its unique design and aesthetics. It received two Best of Best awards at the Red Dot Award in product design and Communication Design in user interface.
By running this special treatment center, KAIST will conduct research on how to build an optimized model for efficient negative pressure medical units. This research is expected to lead to advances in waste water treatment systems, mobile bathrooms optimized for infectious cases, and MCM user interfaces for electronic devices, etc.
Professor Taek-Jin Nam, the general director of the project and design, said “if there is a gymnasium available, we can convert it into a special treatment center fitted with a waste water treatment system, and pressure equipment in two weeks even without additional infrastructure.”
The head of the KAIST New Deal R&D Initiative Choongsik Bae said, “our MCM research started in July of last year, and in just over a year, it has become a successful and innovative case that has undergone trials and become commercialized in a short period of time.” He added, “In response to COVID-19, KAIST is conducting research and empirical studies, not just in relation to the MCM, but in other areas of disease control as well.”
Based on the excellent disease control technologies developed by KAIST research teams, the KAIST Action for Respiratory Epidemics is conducting technology transfers and industrialization, and is developing a Korean disease control package model
2021.09.15 View 10994 -
Recipe for Success: Reputations Start from Inner Circles
A study on social network data of EDM DJs finds the relationship between social standing and identity building
If you would like to succeed in your career, carve out your own distinctiveness, then break your boundaries along with collaborators. This sounds very common. However, a study on social networks has proven that is the recipe for success.
A recent research on electric dance music DJs’ music identity and their reputation found that music DJs with a distinct genre identity as well as network positions combining brokerage and cohesion tend to place higher in terms of their social standing.
What do Calvin Harris, the star of Electro house, Diplo, the icon of Moombahton & Trap, Sebastian Ingrosso, the master of Progressive House, and Armin Van Buuren, the leader of Trance have in common? One commonality of these star DJs in the electronic music market is that they are the leaders who build their genres with solid musical identities and are artists who constantly try experimental and innovative connections with other genres.
Professor Wonjae Lee and Dr. Hyeongseok Wi from the Graduate School of Culture and Technology analyzed the playlist data performed by electronic dance music (EDM) DJs at several EDM festivals that were popular around the world before COVID-19 and the track data that they released during that period.
“This study investigates how social standing is attained within a professional group of artists whose members play a key role in evaluating their artistic products in the EDM market,” said Professor Lee.
Particularly, the team considered DJs' social standing as an effective means of ensuring the quality of their artwork in emerging music markets such as EDM and identified two important factors, the musical identity and the social position within the professional DJ’s group.
They analyzed the data from 3,164 playlists of 815 DJs who performed at nine festivals held from 2013 to 2016 as a sort of citation network among DJs, and transformed it into network data to measure social positions among the DJs. They considered the DJs who received a lot of citations from other DJs as having a high social standing. In addition, the genre, beats per minute (BPM), and key scale data of the songs released during the period were quantified to analyze the association with the musical identity.
First, the results of analysis of the released track data demonstrated that focused distinct musical identity is correlated with social standing among EDM DJs. The EDM market is an emerging specialist market that is constantly developing and differentiating new styles and genres. It includes artists who establish value criteria and demarcate categorical space into separate identity positions reflecting the artistic forms of a similar type.
Second, this study focuses on the two advantages of two types of social positioning, brokerage and cohesive, which can effectively reduce uncertainty in the market. The results show that DJs with a hybrid position, combining elements of both brokerage and cohesion, have higher social standing. This hybrid position is the most advantageous position for controlling new opportunities and inflows of resources and for utilizing them. Unlike existing studies that divide the merits of the two positions into a dichotomy, this study follows the practice of recent studies that show that the two positions can generate synergy in a complementary manner.
The remix culture prominent in EDM provides a convincing explanation for this phenomenon. Because constructing playlist sets represents a DJ’s main specialty, the ability to creatively combine a variety of tracks using one’s own artistic style is crucial. To showcase their remix skills, DJs skillfully select tracks to maximize the displays of their talent. Recognized DJs prefer to select tracks from other genres, borrowing from existing contexts and creating new reinterpretations while drawing upon their own musical backgrounds.
“Acquiring social acknowledgement within a professional group is an effective way to ensure the quality of products they produce and a strong reputation,” explained Professor Lee.
The research team also pointed out the unique case of Techno DJs, who are showing Galápagos syndrome by avoiding crossover between genres and sticking to their own musical identity, unlike most genres in EDM. This research was reported in PLos ONE on Aug. 25 and funded by KAIST and the BK21 Plus Postgraduate Organization for Content Science.
-ProfileProfessor Wonjae LeeGraduate School of Culture TechnologyKAIST
-PublicationHyeongseok Wi, Wonjae Lee “Stars inside have reached outside: The effects of electronic dance music DJ’s social standing and musical identity on track success,” Aug.25, 2021 PLosONE (https://doi.org/10.1371/journal.pone.0254618)
2021.09.09 View 6856 -
How Stingrays Became the Most Efficient Swimmers in Nature
Study shows the hydrodynamic benefits of protruding eyes and mouth in a self-propelled flexible stingray
With their compressed bodies and flexible pectoral fins, stingrays have evolved to become one of nature’s most efficient swimmers. Scientists have long wondered about the role played by their protruding eyes and mouths, which one might expect to be hydrodynamic disadvantages.
Professor Hyung Jin Sung and his colleagues have discovered how such features on simulated stingrays affect a range of forces involved in propulsion, such as pressure and vorticity. Despite what one might expect, their research team found these protruding features actually help streamline the stingrays.
‘The influence of the 3D protruding eyes and mouth on a self-propelled flexible stingray and its underlying hydrodynamic mechanism are not yet fully understood,” said Professor Sung. “In the present study, the hydrodynamic benefit of protruding eyes and mouth was explored for the first time, revealing their hydrodynamic role.”
To illustrate the complex interplay between hydrodynamic forces, the researchers set to work creating a computer model of a self-propelled flexible plate. They clamped the front end of the model and then forced it to mimic the up-and-down harmonic oscillations stingrays use to propel themselves.
To re-create the effect of the eyes and mouth on the surrounding water, the team simulated multiple rigid plates on the model. They compared this model to one without eyes and a mouth using a technique called the penalty immersed boundary method.
“Managing random fish swimming and isolating the desired purpose of the measurements from numerous factors was difficult,” Sung said. “To overcome these limitations, the penalty immersed boundary method was adopted to find the hydrodynamic benefits of the protruding eyes and mouth.”
The team discovered that the eyes and mouth generated a vortex of flow in the forward-backward , which increased negative pressure at the simulated animal’s front, and a side-to-side vortex that increased the pressure difference above and below the stingray. The result was increased thrust and accelerated cruising.
Further analysis showed that the eyes and mouth increased overall propulsion efficiency by more than 20.5% and 10.6%, respectively.
Researchers hope their work, driven by curiosity, further stokes interest in exploring fluid phenomena in nature. They are hoping to find ways to adapt this for next-generation water vehicle designs based more closely on marine animals.
This study was supported by the National Research Foundation of Korea and the State Scholar Fund from the China Scholarship Council.
-ProfileProfessor Hyung Jin SungDepartment of Mechanical EngineeringKAIST
-PublicationHyung Jin Sung, Qian Mao, Ziazhen Zhao, Yingzheng Liu, “Hydrodynamic benefits of protruding eyes and mouth in a self-propelled flexible stingray,” Aug.31, 2021, Physics of Fluids
(https://doi.org/10.1063/5.0061287)
-News release from the American Institute of Physics, Aug.31, 2021
2021.09.06 View 7191 -
Quantum Emitters: Beyond Crystal Clear to Single-Photon Pure
‘Nanoscale Focus Pinspot’ can quench only the background noise without changing the optical properties of the quantum emitter and the built-in photonic structure
Photons, fundamental particles of light, are carrying these words to your eyes via the light from your computer screen or phone. Photons play a key role in the next-generation quantum information technology, such as quantum computing and communications. A quantum emitter, capable of producing a single, pure photon, is the crux of such technology but has many issues that have yet to be solved, according to KAIST researchers.
A research team under Professor Yong-Hoon Cho has developed a technique that can isolate the desired quality emitter by reducing the noise surrounding the target with what they have dubbed a ‘nanoscale focus pinspot.’ They published their results on June 24 in ACS Nano.
“The nanoscale focus pinspot is a structurally nondestructive technique under an extremely low dose ion beam and is generally applicable for various platforms to improve their single-photon purity while retaining the integrated photonic structures,” said lead author Yong-Hoon Cho from the Department of Physics at KAIST.
To produce single photons from solid state materials, the researchers used wide-bandgap semiconductor quantum dots — fabricated nanoparticles with specialized potential properties, such as the ability to directly inject current into a small chip and to operate at room temperature for practical applications. By making a quantum dot in a photonic structure that propagates light, and then irradiating it with helium ions, researchers theorized that they could develop a quantum emitter that could reduce the unwanted noisy background and produce a single, pure photon on demand.
Professor Cho explained, “Despite its high resolution and versatility, a focused ion beam typically suppresses the optical properties around the bombarded area due to the accelerated ion beam’s high momentum. We focused on the fact that, if the focused ion beam is well controlled, only the background noise can be selectively quenched with high spatial resolution without destroying the structure.”
In other words, the researchers focused the ion beam on a mere pin prick, effectively cutting off the interactions around the quantum dot and removing the physical properties that could negatively interact with and degrade the photon purity emitted from the quantum dot.
“It is the first developed technique that can quench the background noise without changing the optical properties of the quantum emitter and the built-in photonic structure,” Professor Cho asserted.
Professor Cho compared it to stimulated emission depletion microscopy, a technique used to decrease the light around the area of focus, but leaving the focal point illuminated. The result is increased resolution of the desired visual target.
“By adjusting the focused ion beam-irradiated region, we can select the target emitter with nanoscale resolution by quenching the surrounding emitter,” Professor Cho said. “This nanoscale selective-quenching technique can be applied to various material and structural platforms and further extended for applications such as optical memory and high-resolution micro displays.” Korea’s National Research Foundation and the Samsung Science and Technology Foundation supported this work.
-PublicationMinho Choi, Seongmoon Jun, and Yong-Hoon Cho et al. ACS Nano‘Nanoscale Focus Pinspot for High-Purity Quantum Emitters via Focused-Ion-Beam-Induced Luminescence Quenching,’(https://pubs.acs.org/doi/10.1021/acsnano.1c00587)
-ProfileProfessor Yong-Hoon ChoQuantum & Nanobio Photonics Laboratoryhttp://qnp.kaist.ac.kr/
Department of PhysicsKAIST
2021.09.02 View 9968 -
A Mechanism Underlying Most Common Cause of Epileptic Seizures Revealed
An interdisciplinary study shows that neurons carrying somatic mutations in MTOR can lead to focal epileptogenesis via non-cell-autonomous hyperexcitability of nearby nonmutated neurons
During fetal development, cells should migrate to the outer edge of the brain to form critical connections for information transfer and regulation in the body. When even a few cells fail to move to the correct location, the neurons become disorganized and this results in focal cortical dysplasia. This condition is the most common cause of seizures that cannot be controlled with medication in children and the second most common cause in adults.
Now, an interdisciplinary team studying neurogenetics, neural networks, and neurophysiology at KAIST has revealed how dysfunctions in even a small percentage of cells can cause disorder across the entire brain. They published their results on June 28 in Annals of Neurology.
The work builds on a previous finding, also by a KAIST scientists, who found that focal cortical dysplasia was caused by mutations in the cells involved in mTOR, a pathway that regulates signaling between neurons in the brain.
“Only 1 to 2% of neurons carrying mutations in the mTOR signaling pathway that regulates cell signaling in the brain have been found to include seizures in animal models of focal cortical dysplasia,” said Professor Jong-Woo Sohn from the Department of Biological Sciences. “The main challenge of this study was to explain how nearby non-mutated neurons are hyperexcitable.”
Initially, the researchers hypothesized that the mutated cells affected the number of excitatory and inhibitory synapses in all neurons, mutated or not. These neural gates can trigger or halt activity, respectively, in other neurons. Seizures are a result of extreme activity, called hyperexcitability. If the mutated cells upend the balance and result in more excitatory cells, the researchers thought, it made sense that the cells would be more susceptible to hyperexcitability and, as a result, seizures.
“Contrary to our expectations, the synaptic input balance was not changed in either the mutated or non-mutated neurons,” said Professor Jeong Ho Lee from the Graduate School of Medical Science and Engineering. “We turned our attention to a protein overproduced by mutated neurons.”
The protein is adenosine kinase, which lowers the concentration of adenosine. This naturally occurring compound is an anticonvulsant and works to relax vessels. In mice engineered to have focal cortical dysplasia, the researchers injected adenosine to replace the levels lowered by the protein. It worked and the neurons became less excitable.
“We demonstrated that augmentation of adenosine signaling could attenuate the excitability of non-mutated neurons,” said Professor Se-Bum Paik from the Department of Bio and Brain Engineering.
The effect on the non-mutated neurons was the surprising part, according to Paik. “The seizure-triggering hyperexcitability originated not in the mutation-carrying neurons, but instead in the nearby non-mutated neurons,” he said.
The mutated neurons excreted more adenosine kinase, reducing the adenosine levels in the local environment of all the cells. With less adenosine, the non-mutated neurons became hyperexcitable, leading to seizures.
“While we need further investigate into the relationship between the concentration of adenosine and the increased excitation of nearby neurons, our results support the medical use of drugs to activate adenosine signaling as a possible treatment pathway for focal cortical dysplasia,” Professor Lee said.
The Suh Kyungbae Foundation, the Korea Health Technology Research and Development Project, the Ministry of Health & Welfare, and the National Research Foundation in Korea funded this work.
-Publication:Koh, H.Y., Jang, J., Ju, S.H., Kim, R., Cho, G.-B., Kim, D.S., Sohn, J.-W., Paik, S.-B. and Lee, J.H. (2021), ‘Non–Cell Autonomous Epileptogenesis in Focal Cortical Dysplasia’ Annals of Neurology, 90: 285 299. (https://doi.org/10.1002/ana.26149)
-ProfileProfessor Jeong Ho Lee Translational Neurogenetics Labhttps://tnl.kaist.ac.kr/ Graduate School of Medical Science and Engineering KAIST
Professor Se-Bum Paik Visual System and Neural Network Laboratory http://vs.kaist.ac.kr/ Department of Bio and Brain EngineeringKAIST
Professor Jong-Woo Sohn Laboratory for Neurophysiology, https://sites.google.com/site/sohnlab2014/home Department of Biological SciencesKAIST
Dr. Hyun Yong Koh Translational Neurogenetics LabGraduate School of Medical Science and EngineeringKAIST
Dr. Jaeson Jang Ph.D.Visual System and Neural Network LaboratoryDepartment of Bio and Brain Engineering KAIST
Sang Hyeon Ju M.D.Laboratory for NeurophysiologyDepartment of Biological SciencesKAIST
2021.08.26 View 12552 -
Brain-Inspired Highly Scalable Neuromorphic Hardware Presented
Neurons and synapses based on single transistor can dramatically reduce the hardware cost and accelerate the commercialization of neuromorphic hardware
KAIST researchers fabricated a brain-inspired highly scalable neuromorphic hardware by co-integrating single transistor neurons and synapses. Using standard silicon complementary metal-oxide-semiconductor (CMOS) technology, the neuromorphic hardware is expected to reduce chip cost and simplify fabrication procedures.
The research team led by Yang-Kyu Choi and Sung-Yool Choi produced a neurons and synapses based on single transistor for highly scalable neuromorphic hardware and showed the ability to recognize text and face images. This research was featured in Science Advances on August 4.
Neuromorphic hardware has attracted a great deal of attention because of its artificial intelligence functions, but consuming ultra-low power of less than 20 watts by mimicking the human brain. To make neuromorphic hardware work, a neuron that generates a spike when integrating a certain signal, and a synapse remembering the connection between two neurons are necessary, just like the biological brain. However, since neurons and synapses constructed on digital or analog circuits occupy a large space, there is a limit in terms of hardware efficiency and costs. Since the human brain consists of about 1011 neurons and 1014 synapses, it is necessary to improve the hardware cost in order to apply it to mobile and IoT devices.
To solve the problem, the research team mimicked the behavior of biological neurons and synapses with a single transistor, and co-integrated them onto an 8-inch wafer. The manufactured neuromorphic transistors have the same structure as the transistors for memory and logic that are currently mass-produced. In addition, the neuromorphic transistors proved for the first time that they can be implemented with a ‘Janus structure’ that functions as both neuron and synapse, just like coins have heads and tails.
Professor Yang-Kyu Choi said that this work can dramatically reduce the hardware cost by replacing the neurons and synapses that were based on complex digital and analog circuits with a single transistor. "We have demonstrated that neurons and synapses can be implemented using a single transistor," said Joon-Kyu Han, the first author. "By co-integrating single transistor neurons and synapses on the same wafer using a standard CMOS process, the hardware cost of the neuromorphic hardware has been improved, which will accelerate the commercialization of neuromorphic hardware,” Han added.This research was supported by the National Research Foundation (NRF) and IC Design Education Center (IDEC).
-PublicationJoon-Kyu Han, Sung-Yool Choi, Yang-Kyu Choi, et al.“Cointegration of single-transistor neurons and synapses by nanoscale CMOS fabrication for highly scalable neuromorphic hardware,” Science Advances (DOI: 10.1126/sciadv.abg8836)
-ProfileProfessor Yang-Kyu ChoiNano-Oriented Bio-Electronics Labhttps://sites.google.com/view/nobelab/
School of Electrical EngineeringKAIST
Professor Sung-Yool ChoiMolecular and Nano Device Laboratoryhttps://www.mndl.kaist.ac.kr/
School of Electrical EngineeringKAIST
2021.08.05 View 10415 -
A Study Reveals What Triggers Lung Damage during COVID-19
A longitudinal study of macrophages from SARS-CoV-2 infected lungs offers new insights into dynamic immunological changes
A KAIST immunology research team found that a specific subtype of macrophages that originated from blood monocytes plays a key role in the hyper-inflammatory response in SARS-CoV-2 infected lungs, by performing single-cell RNA sequencing of bronchoalveolar lavage fluid cells. This study provides new insights for understanding dynamic changes in immune responses to COVID-19.
In the early phase of COVID-19, SARS-CoV-2 infected lung tissue and the immediate defense system is activated. This early and fast response is called ‘innate immunity,’ provided by immune cells residing in lungs. Macrophages are major cell types of the innate immune system of the lungs, and newly differentiated macrophages originating from the bloodstream also contribute to early defenses against viruses.
Professor Su-Hyung Park and his collaborators investigated the quantitative and qualitative evaluation of immune responses in the lungs of SARS-CoV-2 infected ferrets. To overcome the limitations of research using patient-originated specimens, the researchers used a ferret infection model to obtain SARS-CoV-2 infected lungs sequentially with a defined time interval.
The researchers analyzed the 10 subtypes of macrophages during the five-day course of SARS-CoV-2 infection, and found that infiltrating macrophages originating from activated monocytes in the blood were key players for viral clearance as well as damaged lung tissue. Moreover, they found that the differentiation process of these inflammatory macrophages resembled the immune responses in the lung tissue of severe COVID-19 patients.
Currently, the research team is conducting a follow-up study to identify the dynamic changes in immune responses during the use of immunosuppressive agents to control hyper-inflammatory response called ‘cytokine storm’ in patients with COVID-19.
Dr. Jeong Seok Lee, the chief medical officer at Genome Insight Inc., explained, “Our analysis will enhance the understanding of the early features of COVID-19 immunity and provide a scientific background for the more precise use of immunosuppressive agents targeting specific macrophage subtypes.”
“This study is the first longitudinal study using sequentially obtained immune cells originating from SARS-CoV-2 infected lungs. The research describes the innate immune response to COVID-19 using single cell transcriptome data and enhances our understanding of the two phases of inflammatory responses,” Professor Park said.
This work was supported by the Ministry of Health and Welfare and KAIST, and was published in Nature Communications on July 28.
-PublicationSu-Hyung Park, Jeong Seok Lee, Su-Hyung Park et al. “Single-cell transcriptome of bronchoalverolar lavage fluid reveals sequential change of macrophages during SARS-CoV-2 infection in ferrets” Nature Communications (https://doi.org/10.1038/s41467-021-24807-0)
-ProfileProfessor Su-Hyung ParkLaboratory of Translational Immunology and Vaccinologyhttps://ltiv.kaist.ac.kr/
Graduate School of Medical Science and EngineeringKAIST
2021.08.04 View 12324