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President Shin to be Honored from Northwestern University
(KAIST President Sung-Chul Shin)
President Sung-Chul Shin has been named the recipient of the Distinguished Career Achievement Award 2019 for Alumni of Materials Science and Engineering at Northwestern University.
The awards committee announced last month that the committee decided to award President Shin in recognition of his significant contribution toward materials research, particularly in the field of magnetic materials, and also for the leadership he has demonstrated in higher education. The awards ceremony will take place on May 16 at Northwestern University.
President Shin earned his PhD in material physics at Northwestern in 1984 after completing his MS in condensed matter physics at KAIST in 1977. He is also a graduate of applied physics from Seoul National University.
President Shin, an accomplished scholar in the field of nanoscience and a pioneer of research in nanospinics, has held numerous fellowships including the American Physical Society and received scholarly honor from the Asian Union Magnetics Societies. His research focuses on the artificial synthesis and characterization of nonmagnetic materials, magnetic anisotropy, and magneto-optical phenomena. While studying at Northwestern, he produced novel superlattice multilayer thin film structures with bismuth and lead telluride, noting that they have similar structures.
With his expertise, he joined KAIST in 1989 to dedicate himself to academic contributions. During his professorship in the Department of Physics, he produced about 300 journal papers and 37 patents while fostering 80 graduate students. He served as the first president in Daegu-Gyeongbuk Scientific Technology Research Institute (DGIST) for six years from 2011.
2019.01.09 View 3650 -
Optimal Immuno-Therapeutic Strategies for Liver Cancer
KAIST medical scientists have presented a heterogeneity of immune cell exhaustion in the cancer environment, providing evidence and rationale for designing optimal strategies for immune checkpoint inhibitors in liver cancer patients.
They succeeded in distinguishing the hepatocellular carcinoma group from the exhausted tumor infiltrating immune cell composition of liver cancer patients. The study, conducted in collaboration with Asan Medical Center, confirmed the applicability for liver cancer patients, providing a new path for personalized precision medicine as well as a new model for translational research.
Our immune system is able to destroy cancerous cells in our body, however sometimes cancer cells can adapt and mutate, effectively hiding from our immune system. One of the mechanisms that has evolved to prevent eradication by the immune system is to functionally silence effector T cells, termed T-cell exhaustion, that is mainly mediated by immune checkpoint molecules such as PD-1, TIM-3, and LAG-3.
Recent breakthroughs and encouraging clinical results with various immune checkpoint inhibitors (ICIs), such as anti-PD-1 monoclonal antibodies (mAbs) and anti-CTLA-4 mAbs, have demonstrated tremendous potential to cure cancers through the immune activation of exhausted T cells. Immune checkpoint inhibitors showed significant clinical benefits for several types of cancers, leading to their wide application in clinical practice.
Anti-PD1 blocking antibodies are one of the most representative agents in this class of drug. However, it has been challenging to precisely understand the biological and clinical significance of T-cell exhaustion in cancer. A KAIST research team led by Professor Su-Hyung Park reported the heterogeneity of T-cell exhaustion in hepatocellular carcinoma (HCC) and its potential clinical implications in Gastroenterology on December 4.
The team revealed that heterogeneous T-cell exhaustion status is determined by the differential PD-1 expression levels in CD8+ T cells in liver cancer patients. The authors found that tumor-infiltrating CD8+ T cells with high PD-1 expression from liver cancer patients are functionally impaired and co-express other immune checkpoint receptors such as TIM-3 and/or LAG3, compared to those with low PD-1 expression.
Moreover, based on these results, the authors suggested that liver cancer patients can be classified into two distinct subgroups. Patients having high PD-1 expression levels in the tumor microenvironment showed more aggressive tumor features and biomarkers predicting a favorable response to anti-PD1 therapy. The research team also demonstrated that only liver cancer patients having high PD-1 expression are susceptible to combined immune checkpoint blockade-based therapies.
Prof. Park said, “The new classification of liver cancer patients identified by this study can be utilized as a biomarker to predict the response of current cancer immunotherapy targeting the PD-1 pathway.” He also said they will continue to conduct research on T-cell exhaustion and activation in various types of cancer, which could lead to a better understanding of T-cell response against cancer, thereby providing evidence for future cancer immunotherapy to achieve the ultimate goal to prolong the survival of cancer patients.
2018.12.18 View 5291 -
Distinguished Professor Lee Re-Appointed As Co-Chair of the Global Future Council on Biotechnology
(Distinguished Professor Sang Yup Lee)
Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering was re-appointed as the co-chair of the Global Future Council on Biotechnology at the World Economic Forum during the annual GFC meeting in Dubai, UAE last week. Elizabeth O’Day, founder and CEO of Olaris Therapeutics, will co-chair the council with him for two years.
Professor Lee served as the inaugural co-chair of the council for two years from 2016 with Professor Feng Zhang from the Broad Institute of MIT and Harvard.
The World Economic Forum’s Global Future Councils on Biotechnology is comprised of 14 members and aims to identify policy opportunities to help accelerate new biotechnological discoveries and applications while guiding dialogue with consumers about their implications.
Professor Lee, who has made significant research breakthroughs in the field of systems metabolic engineering, received the George Washington Carver Award, the PV Danckwerts Memorial Lecture Award, and the Eni Award this year.
2018.11.19 View 3863 -
Controlling Crystal Size of Organic Semiconductors
A KAIST research team led by Professor Steve Park from the Department of Materials Science and Engineering
Recently, solution-processable organic semiconductors are being highlighted for their potential application in printed electronics, becoming a feasible technique to fabricate large-area flexible thin film at a low cost. The field-effect mobility of small-molecule organic semiconductors is dependent on the crystallinity, crystal orientation, and crystal size. A variety of solution-based coating techniques, such as ink-jet printing, dip-coating, and solution shearing have been developed to control the crystallinity and crystal orientation, but a method for developing techniques to increase the crystal size of organic semiconductors is still needed.
To overcome this issue, the research team developed an inorganic polymer micropillar-based solution shearing system to increase the crystal size of an organic semiconductor with pillar size. Using this technique, the crystallization process of organic semiconductors can be controlled precisely, and therefore large-area organic semiconductor thin film with controlled crystallinity can be fabricated.
A variety of solution-based coating techniques cannot control the fluid-flow of solutions appropriately, so the solvent evaporates randomly onto the substrate, which has difficulty in the fabrication of organic semiconductor thin film with a large crystal size.
The research team integrated inorganic polymer microstructures into the solution shearing blade to solve this issue. The inorganic polymer can easily be microstructured via conventional molding techniques, has high mechanical durability, and organic solvent resistance. Using the inorganic polymer-based microstructure blade, the research team controlled the size of small molecule organic semiconductors by tuning the shape and dimensions of the microstructure. The microstructures in the blade induce the sharp curvature regions in the meniscus line that formed between the shearing blade and the substrate, and therefore nucleation and crystal growth can be regulated. Hence, the research team fabricated organic semiconductor thin-film with large crystals, which increases the field-effect mobility.
The research team also demonstrated a solution shearing process on a curved surface by using a flexible inorganic polymer-based shearing blade, which expands the applicability of solution shearing.
Professor Park said, “Our new solution shearing system can control the crystallization process precisely during solvent evaporation.” He added, “This technique adds another key parameter that can be utilized to tune the property of thin films and opens up a wide variety of new applications.
The results of this work entitled “Inorganic Polymer Micropillar-Based Solution Shearing of Large-Area Organic Semiconductor Thin Films with Pillar-Size-Dependent Crystal Size” was published in the July 2018 issue of Advanced Materials as a cover article.
2018.10.30 View 6172 -
Professor Baik Awarded Sangsan Young Mathematician Prize
(Professor Hyungryul Baik)
Professor Hyungryul Baik from the Department of Mathematical Sciences was honored as the recipient of the 2018 Sangsan Prize for Young Mathematicians by the Korean Mathematical Society (KMS).
The Sangsan Prize recognizes young mathematicians who finished their degree within the previous five years and have begun an outstanding research career. Professor Baik was recognized for his studies in the fields of low-dimensional topology, geophysical mathematics, and geometric theory. In particular, his Ph.D. dissertation presented a new criterion that completely identifies the hyperbolic surface group, making an inference about the nature of the hyperbolic manifold group.
Recently, Professor Baik co-published a paper entitled Spaces of Invariant Circular Orders of Groups with Professor Eric Samperton at the University of California Santa Barbara in the renowned academic journal Groups, Geometry, and Dynamics in 2018.
Professor Baik earned his BS at KAIST and finished his MS and Ph.D. in mathematics in 2014 at Cornell University. He joined KAIST as a faculty member last year.
2018.10.30 View 6724 -
KAIST Launches Woorisae II
Professor Sejin Kwon from the Department of Aerospace Engineering and his team succeeded in launching a science rocket, named ‘Woorisae II’ at Saemanguem reclamation. This rocket was developed in collaboration with the Satellite Technology Research Lab (SaRTec).
The test-firing was conducted at 10:43 am on Sunday October 28, 2018 (35°N 42’ 06” 126°E 33’ 36”, Radius of 0.6NM). This launch was the follow-up to the previous launch that was cancelled due to not gaining approval for using the airspace.
Professor Kwon’s team put a great deal of effort into securing the land for the rocket launch. As a result, they got approval from the Saemangeum Development and Investment Agency for the land and the Ministry of Land, Infrastructure and Transport for the use of the airspace. The Republic of Korea Air Force and United States Air Force also approved the use of the airspace for the launch of the science rocket for research purposes.
Woorisae II is 2.2 meters long with a diameter of 20cm, and weighs 13kg without a payload. The rocket is powered by a hybrid rocket with hydrogen peroxide oxidizer producing 100 kg of force. The Woorisae II sounding rocket was designed to burn for five seconds and then continue inertial flight for 20 seconds. The target altitude of Woorisae II was set at 3,300 feet to comply with the airspace approval.
The team developed the core components, including a hybrid rocket propulsion system, flight computer and parachute recovery system, as well as a ground control station. The flight data was transmitted to the ground station and recorded to onboard computer memory.
When a malfunction occurs during the flight, Woorisae II was designed to terminate the power flight for safety by shutting the propellant valve and deploying the recovery parachute. All the rocket subsystems and components were developed and supplied by domestic startup companies such as INOCOM and NARA SPACE TEHCNOLOGY.
Generally, sounding rockets reach an altitude beyond 30km and are widely used for testing rocket engines and reentry materials as well as for conducting microgravity experiments. Instruments for atmospheric science can also be installed to measure fine dust and high altitude atmosphere. Besides these science and technology purposes, most advanced spacefaring countries have sounding rocket programs to train and educate young people in the field of space science.
Professor Kwon said, “We will plan to launch upgraded rockets on November 4 and December 6 because we already received approval from the related agencies for using this land and airspace. Based on the experiment, we are planning to develop a cost-efficient small launch vehicle that is capable of delivering a cube satellite into Earth’s orbit.”
(Photos of preparing the rocket launch)
2018.10.29 View 10415 -
Dr. Sejeong Kim Recognized as Excellent Young Scientist
(Dr. Sejeong Kim)
Dr. Sejeong Kim, a postdoctoral research associate in the School of Mathematical and Physical Sciences at the University of Technology Sydney was honored to receive the Excellence Award for a Young Scientist by the Korea Federation of Women’s Science & Technology Association (KOFWST). The award ceremony will be held on October 31 in Seoul.
KOFWST recognizes ten promising young female scientists and engineers every year who show significant potential, passion, and remarkable achievement in their work. The awardees are selected among those who finished their degree within the previous five years. Dr. Kim earned her Ph.D. in physics at KAIST in 2014 and was selected as the winner in the field of physics in recognition of her outstanding research activities in photonics.
Dr. Kim conducted various research activities in the field of photonics and was published in high impact journals including Nano Letters and Advanced materials. In July, she developed the first photonic cavity from van der Waals materials and published the study in Nature Communications titled “Photonic Crystal Cavities from Hexagonal Boron Nitride.” At UTS, she carries out research activities supervised by Professor Igor Aharonovich and has engaged in many science outreach activities.
2018.10.18 View 5820 -
Scientist of October, Professor Haeshin Lee
(Professor Haeshin Lee from the Department of Chemistry)
Professor Haeshin Lee from the Department of Chemistry received the ‘Science and Technology Award of October’ from the Ministry of Science and ICT and the National Research Foundation of Korea for his contribution to developing an antibleeding injection needle. This novel outcome will fundamentally prevent the problem of secondary infections of AIDS, Ebola and Hepatitis viruses transmitting from patients to medical teams.
This needle’s surface is coated with hemostatic materials. Its concept is simple and the key to this technology is to make materials that are firmly coated on the needle so that they can endure frictional force when being injected into skin and blood vessels. Moreover, the materials should be adhesive to skin and the interior of blood vessels, but harmless to humans.
Professor Lee found a solution from natural polymer ingredients. Catecholamine can be found in mussels. Professor Lee conjugated catechol groups on the chitosan backbone. He applied this mussel-inspired adhesive polymer Chitosan-catechol, which immediately forms an adhesive layer with blood, as a bioadhesion for the antibleeding injection needle.
Professor Lee said, “Chitosan-catechol, which copies the adhesive mechanism of mussels, shows high solubility in physiological saline as well as great mucoadhesion. Hence, it is perfectly suitable for coating the injection needle. Combining it with proteins allows for efficient drug delivery to the heart, which is a challenging injection location, so it will be also useful for treating incurable heart disease.”
2018.10.05 View 10406 -
The 1st Korea Toray Science and Technology Awardee, Prof. Sukbok Chang
(Distinguished Professor Sukbok Chang from the Department of Chemistry)
The Korea Toray Science Foundation (KTSF) awarded the first Korea Toray Science Technology Award in basic science to Distinguished Professor Sukbok Chang from the Department of Chemistry on September 19.
KTSF was established in January 2018, and its award goes to researchers who have significantly contributed to the development of chemistry and materials research with funds to support research projects.
Distinguished Professor Chang has devoted himself in organocatalysis research; in particular, his work on catalysts for effective lactam formation, which was an intricate problem, received great attention.
The award ceremony will take place in The Federation of Korean Industries Hall on October 31. KTFS board members, judges, and the CEO of Toray Industries Akihiro Nikkaku will attend the ceremony. Also, Dr. Ryoji Noyori, the Nobel Laureate in Chemistry, will give a talk on the role of chemistry and creative challenges as a researcher.
2018.10.04 View 8713 -
Spray Coated Tactile Sensor on a 3-D Surface for Robotic Skin
Robots will be able to conduct a wide variety of tasks as well as humans if they can be given tactile sensing capabilities.
A KAIST research team has reported a stretchable pressure insensitive strain sensor by using an all solution-based process. The solution-based process is easily scalable to accommodate for large areas and can be coated as a thin-film on 3-dimensional irregularly shaped objects via spray coating. These conditions make their processing technique unique and highly suitable for robotic electronic skin or wearable electronic applications.
The making of electronic skin to mimic the tactile sensing properties of human skin is an active area of research for various applications such as wearable electronics, robotics, and prosthetics. One of the major challenges in electronic skin research is differentiating various external stimuli, particularly between strain and pressure. Another issue is uniformly depositing electrical skin on 3-dimensional irregularly shaped objects.
To overcome these issues, the research team led by Professor Steve Park from the Department of Materials Science and Engineering and Professor Jung Kim from the Department of Mechanical Engineering developed electronic skin that can be uniformly coated on 3-dimensional surfaces and distinguish mechanical stimuli. The new electronic skin can also distinguish mechanical stimuli analogous to human skin. The structure of the electronic skin was designed to respond differently under applied pressure and strain. Under applied strain, conducting pathways undergo significant conformational changes, considerably changing the resistance. On the other hand, under applied pressure, negligible conformational change in the conducting pathway occurs; e-skin is therefore non-responsive to pressure. The research team is currently working on strain insensitive pressure sensors to use with the developed strain sensors.
The research team also spatially mapped the local strain without the use of patterned electrode arrays utilizing electrical impedance tomography (EIT). By using EIT, it is possible to minimize the number of electrodes, increase durability, and enable facile fabrication onto 3-dimensional surfaces.
Professor Park said, “Our electronic skin can be mass produced at a low cost and can easily be coated onto complex 3-dimensional surfaces. It is a key technology that can bring us closer to the commercialization of electronic skin for various applications in the near future.”
The result of this work entitled “Pressure Insensitive Strain Sensor with Facile Solution-based Process for Tactile Sensing Applications” was published in the August issue of ACS Nano as a cover article.
(Figure: Detecting mechanical stimuli using electrical impedance tomography.)
2018.09.21 View 8530 -
Distinguished Professor Sang Yup Lee Announced as the Eni Award Recipient
(Distinguished Professor Sang Yup Lee)
Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering will be awarded the 2018 Eni Advanced Environmental Solutions Prize in recognition of his innovations in the fields of energy and environment. The award ceremony will take place at the Quirinal Palace, the official residence of Italian President Sergio Mattarella, who will also be attending on October 22.
Eni, an Italian multinational energy corporation established the Eni Award in 2008 to promote technological and research innovation of efficient and sustainable energy resources. The Advanced Environmental Solutions Prize is one of the three categories of the Eni Award. The other two categories are Energy Transition and Energy Frontiers. The Award for Advanced Environmental Solutions recognizes a researcher or group of scientists that has achieved internationally significant R&D results in the field of environmental protection and recovery. The Eni Award is referred to as the Nobel Award in the fields of energy and environment.
Professor Lee, a pioneering leader in systems metabolic engineering was honored with the award for his developing engineered bacteria to produce chemical products, fuels, and non-food biomass materials sustainably and with a low environmental impact. He has leveraged the technology to develop microbial bioprocesses for the sustainable and environmentally friendly production of chemicals, fuels, and materials from non-food renewable biomass.
The award committee said that they considered the following elements in assessing Professor Lee’s achievement: the scientific relevance and the research innovation level; the impact on the energy system in terms of sustainability as well as fairer and broader access to energy; and the adequacy between technological and economic aspects.
Professor Lee, who already won two other distinguished prizes such as the George Washington Carver Award and the PV Danckwerts Memorial Lecture Award this year, said, “I am so glad that the international academic community as well as global industry leaders came to recognize our work that our students and research team has made for decades.”
Dr. Lee’s lab has been producing a lot of chemicals in environmentally friendly ways. Among them, many were biologically produced for the first time and some of these processes have been already commercialized. “We will continue to strive for research outcomes with two objectives: First, to develop bio-based processes suitable for sustainable chemical industry. The other is to contribute to the human healthcare system through development of platform technologies integrating medicine and nutrition,” he added.
2018.09.12 View 7807 -
Visualizing Chemical Reaction on Bimetal Surfaces
Catalysts are the result of many chemists searching to unravel the beauty of molecules and the mystery of chemical reactions. Professor Jeong Young Park from the Department of Chemistry, whose research focuses on catalytic chemical reactions, is no exception. His research team recently made breakthroughs in addressing long-standing questions for understanding reaction mechanisms on bimetal catalysts.
During the studies reported in Science Advances, following a publication in Nature Communications this month, Professor Park’s research team identified that the formation of metal–oxide interfaces is the key factor responsible for the synergistic catalytic effect in bimetal catalysts. The team confirmed this fundamental reaction mechanism through in situ imaging of reaction conditions. This is the first visualization of bimetal surfaces under reaction conditions, signifying the role of metal–oxide interfaces in heterogeneous catalysis.
Bimetallic materials have outstanding catalytic performance, which opens a new pathway for controlling electronic structures and binding energy in catalysts. Despite considerable research on various catalytic reaction efficiencies, there are yet unanswered questions on the underlying principles behind the improved performance. Even more, it was very hard to figure out what led to the efficiency because the structure, chemical composition, and oxidation state of bimetallic materials change according to reaction conditions.
Recently, some research groups suggested that oxide–metal interfacial sites formed by the surface segregation of bimetallic nanoparticles might be responsible for the increased catalytic performance. However, they failed to present any definitive evidence illustrating the physical nature or the fundamental role of the oxide–metal interfaces leading to the improved performance.
To specifically address this challenge, the research team carried out in situ observations of structural modulation on platinum–nickel bimetal catalysts under carbon monoxide oxidation conditions with ambient pressure scanning tunneling microscopy and ambient pressure X-ray photoelectron spectroscopy.
The team observed that platinum–nickel bimetal catalysts exhibited a variety of different structures depending on the gas conditions. Under ultrahigh vacuum conditions, the surface exhibited a platinum skin layer on the platinum–nickel alloyed surface, selective nickel segregation followed by the formation of nickel oxide clusters using oxygen gas, and finally the coexistence of nickel oxide clusters on the platinum skin during carbon monoxide oxidation. The research team found that the formation of interfacial platinum–nickel oxide nanostructures is responsible for a highly efficient step in the carbon monoxide oxidation reaction.
These findings illustrate that the enhancement of the catalytic activity on the bimetallic catalyst surface originates from the thermodynamically efficient reaction pathways at the metal–metal oxide interface, which demonstrates a straightforward process for the strong metal–support interaction effect. The formation of these interfacial metal–metal oxide nanostructures increases catalytic activity while providing a thermodynamically efficient reaction pathway by lowering the heat of the reactions on the surface. [J. Kim et al. Adsorbate-driven reactive interfacial Pt-NiO1-x nanostructure formation on the Pt3Ni(111) alloy surface, Science Advances (DOI: 10.1126/sciadv.aat3151 ]
Professor Park said that one way to monitor catalysts is to detect hot electrons associated with energy dissipation and conversion processes during surface reactions. His team led the real-time detection of hot electrons generated on bimetallic PtCo nanoparticles during exothermic hydrogen oxidation. The team successfully clarified the origin of the synergistic catalytic activity of PtCo nanoparticles with corresponding chemicurrent values.
By estimating the chemicurrent yield, the research team conclude that the catalytic properties of the bimetallic nanoparticles are strongly governed by the oxide–metal interface, which facilitates hot electron transfer. [H. Lee et al. Boosting hot electron flux and catalytic activity at metal–oxide interfaces of PtCo bimetallic nanoparticles, Nature Comm, 9, 2235 (2018)].
Professor Park explained, “We feel that the precise measurement of hot electrons on catalysts gives insight into the mechanism for heterogeneous catalysis, which can help with the smart design of highly reactive materials. The control of catalytic activity via electronic engineering of catalysts is a promising prospect that may open the door to the new field of combining catalysis with electronics, called “catalytronics.” He added that the study also establishes a strategy for improving catalytic activity for catalytic reactions in industrial chemical reactors.
Professors Park and Yousung Jung from the Department of Chemical and Biomolecular Engineering and the Graduate School of EEWS conducted this research in collaboration with Professor Bongjin Mun from the Department of Physics at GIST.
Figure 1. Evolution of surface structures of PtNi bimetal surfaces under various ambient conditions.
Figure 2. Formation of Pt-CoO interface leads to the catalytic enhancement of PtCo bimetal catalysts.
2018.07.25 View 10071