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ICISTS 2018: Presence of the Wall, Constraint or Control
A KAIST undergraduates body, ICISTS (International Conference for Integration of Science, Technology and Society) will host the 2018 international conference from July 30 to August 3 at KAIST. Under the theme of “Presence of the Wall: Constraint or Control,” participants will share their opinions on the limits the global world is facing today and look for answers discussing various social issues and technologies. More than 300 students from 60 universities in 15 countries will attend the conference. Speakers include CEO Sebastien Gendron of TransPod Inc., a Canadian company designing and manufacturing ultra-high-speed transportation technology and vehicles, researcher Sven Kreiss from the Visual Intelligence for Transportation of École Polytechnique Fédérale de Lausanne, Professor Des Freedman from the Department of Media and Communications of Goldsmiths, University of London and political scientist-technologist Wilneida Negrón at the Data & Society Research Institute of Ford Foundation in the US. The conference will hold programs to facilitate the exchange of ideas among speakers and participants. Participants will make small teams for free discussions to share their ideas and thoughts about issues affecting the human race. Participants will be also assigned a team project in which they must come up with creative ideas based on the lectures. Moreover, they can try new gadgets from companies during the Experience Session. ICISTS was established in 2005 by undergraduate students from KAIST. The organization holds an international conference every year to explore ways to create harmonization among society, science, and technology. It has grown to become Asia’s largest international student conference. For learn more and register for the program, please visit http://www.icist.org
2018.05.30
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KAIST Class of '78 Celebrates 40-Year Reunion
(from left: Chairman Hyung Kyu Lim from the KAIST Alumni Scholarship Foundation and KAIST President Sung-Chul Shin) The Class of 1978 reunited on May 26 at the College of Business on the KAIST Seoul Campus, which was the main campus when they were students 40 years ago. Now leaders of Korea in the sectors of industry, academia, and research, the Class of ’78 held a homecoming event in celebration of the 40th anniversary of their graduation. Approximately 120 guests attended the event, including the head of the KAIST Alumni Association Ki-Chul Cha, Emeritus Professor Jae-Kyoon Kim, and Emeritus Professor Choong-Ki Kim from the School of Electrical Engineering. The Class of ’78 includes Man Gi Paik from the Ministry of Trade, Industry and Energy, Chairman Hyung Kyu Lim from the KAIST Alumni Scholarship Foundation, President Sang Hyuk Son from Daegu Gyeongbuk Institute of Science & Technology, and Provost and Executive Vice President O Ok Park from KAIST. At the event, the Class of ‘78 donated a scholarship worth 1.5 billion KRW. Chairman Lim said, “We will put every effort into helping KAIST students who will be future leaders. We hope this fund will go toward students who will create new value and contribute to society.” President Shin added, “The effort and affection of the alumni will be a strong foundation for KAIST taking the next big step. In response to the support and affection of 61,125 KAIST alumni, KAIST will make every effort to become a world-leading university.”
2018.05.30
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KAIST-Developed LPV to Launch in LNG-Fueled Port Cleaning Ship in Ulsan
(From left:CEO of LATTICE Technology Kun-Oh Park, research fellow Hwa-Ryong Yu, and Professor Chang ) A KAIST-developed Lattice Pressure Vessel (LPV) will launch inside a 150-ton class port cleaning ship that the Ulsan Port Authority will deploy in December. The ship will operate off the coast of Ulsan and will be the first LNG-fueled public service vessel run by the government. LATTICE Technology, a tech-startup established in 2012 by two KAIST professors, announced last week that the company signed a contract with the Ulsan Port Authority to install the LPV into the hull of the port cleaning ship. The company setup by Professors Daejun Chang and Pål G. Bergan in the Department of Mechanical Engineering accomplished the feat seven years after they first registered their original technology patent. The free-shaped pressure vessel developed by the two professors is applicable to any type of ship structure, a technological breakthrough addressing the wasted installing space of the conventional pressure vessel types that either spherical or cylindrical designs would result in. The LPV has an internal lattice structure for load carrying caused by pressure, providing 50 percent more capacity than that of a cylindrical pressure vessel. According to Professor Chang, the essence of the LPV is an internal, modular structure that carries the load by balancing the pressure on opposite walls. He said that the LPV has a number of merits thanks to the lattice structure. While its structural redundancy improves safety, it is fully scalable in any direction as well as being able to mitigate the sloshing load, resulting in a negligible level of fatigue risk. Its modularity also cuts the production cost. The technology has already earned seven internationally authorized certificates, and the company has already built four prototype tanks. The LPV has significant market potential in the energy storage industry, especially transportation sectors. One imminent application is LNG fuel storage on ships. This cryogenic fuel is expected to replace the conventional marine fuel or heavy fuel oil that is the source of a number of polluting emissions (SOx, NOx, CO2, and particle matters). This LPV technology will contribute to the efficient storage LNG in volume. As liquid hydrogen increasingly emerges to decarbonate the energy mix, the storage and transportation of liquid hydrogen will be also a critical issue. The researchers expect that this LPV technology will be further applied into the entire supply chain of various fields including production, transportation, storage, and utilization of such decarbonated energy sources. Professor Chang said, “Pressure vessels are one of the most common devices for storing materials and energy. The areas for which the LPV can create value will expand into various industrial sectors.” The research team plans to conduct further research and development to realize various LPV applications to store LNG, LPG, liquid hydrogen, carbon dioxide, and steam for ships, land facilities, vehicles, trains, and automobiles. Figure 1: The internal strucutre of a lattice pressure vessel. The middle part of the tank is repetition of a modular lattice strucutre while the end part is specially designed. Figure 2: Lattice pressure vessels in shapes and sizes. Unlike conventional cylinders, the lattice pressure vessel can freely assume different shapes and be scaled up through the repetition of modular internal units. Figure 3: A cylinder tank of 24 m3 and a lattice pressure vessel of 22 m3. They are similar in volume but show a big difference in installation space. Figure 4: LNF-fueld cruised ships with six cylinders and one lattice pressure vessel. Thanks to its high-volume efficiency, the lattice pressure vessel doubles the stroage volume with one sixth of the piping, instruments, and operational complexity.
2018.05.30
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2018 KAIST Research Day Honors Outstanding Research Achievements
(KAIST President Sung-Chul Shin and Professor Jong-Hwan Kim) Professor Jong-Hwan Kim from the School of Electrical Engineering was recognized at the 2018 KAIST Research Day as the Research Grand Prize Awardee. The ten most distinguished research achievements of the past year were also recognized. The Research Grand Prize recognizes the professor whose comprehensive research performance evaluation indicator was the highest over the past five years. The indicator combines the number of research contracts, IPR and royalty income. During the May 25th ceremony, Professor Hyochoong Bang from the Department of Aerospace Engineering and Professor In so Kweon from the School of Electrical Engineering also won the Best Research Award prize. This year, the Research Innovation Award went to Professor Dong Soo Han from the School of Computing. The Research Innovation Award combines scores in the categories of foreign patent registrations, contracts of technological transfer, and income from technology fees, technology consultations, and startups. The Convergence Research Award was given to Professor Junmo Kim from the School of Electrical Engineering and Professor Hyun Myung from the Department of Civil & Environmental Engineering. The Convergence Research Award recognizes the most outstanding research team that created innovative research results over a one-year period. President Sung-Chul Shin said, “KAIST has selected the ten most outstanding research achievements of 2017 conducted by our faculty and researchers. All of them demonstrated exceptional creativity, which opens new research paths in each field though their novelty, innovation, and impact.” KAIST hosts Research Day every year to introduce major research performances at KAIST and share knowledge about the research and development. During Research Day, KAIST also announced the ten most distinguished research achievements contributed by KAIST professors during the previous year. They are listed below. ▲ High-Speed Motion Core Technology for Magnetic Memory by Professor Kab-Jin Kim from the Department of Physics ▲ A Double Well Potential System by Professor Jaeyoung Byeon from the Department of Mathematical Sciences ▲ Cheap and Efficient Dehydrogenation of Alkanes by Professor Mu-Hyun Baik from the Department of Chemistry ▲ A Dynamic LPS Transfer Mechanism for Innate Immune Activation by Professor Ho Min Kim from the Graduate School of Medical Science and Engineering ▲ A Memristive Functional Device and Circuit on Fabric for Fibertronics by Professor Yang-Kyu Choi and Professor Sung-Yool Choi from the School of Electrical Engineering ▲ A Hippocampal Morphology Study Based on a Progressive Template Deformable Model by Professor Jinah Park from the School of Computing ▲ The Development of a 6-DOF Dynamic Response Measurement System for Civil Infrastructure Monitoring by Professor Hoon Sohn from the Department of Civil and Environmental Engineering ▲ Cooperative Tumour Cell Membrane Targeted Phototherapy by Professor Ji-Ho Park from the Department of Bio and Brain Engineering ▲ HUMICOTTA: A 3D-Printed Terracotta Humidifier by Professor Sangmin Bae from the Department of Industrial Design ▲ Ultrathin, Cross-Linked Ionic Polymer Thin Films by Professor Sung Gap Im from the Department of Chemical and Biomolecular Engineering
2018.05.28
View 11340
Recombinant E. Coli As a Biofactory for the Biosynthesis of Diverse Nanomaterials
(Distinguished Professor Lee and PhD candidate Choi) A metabolic research group at KAIST and Chung-Ang University in Korea has developed a recombinant E. coli strain that biosynthesizes 60 different nanomaterials covering 35 elements on the periodic table. Among the elements, the team could biosynthesize 33 novel nanomaterials for the first time, advancing the forward design of nanomaterials through the biosynthesis of various single and multi-elements. The study analyzed the nanomaterial biosynthesis conditions using a Pourbaix diagram to predict the producibility and crystallinity. Researchers studied a Pourbaix diagram to predict the stable chemical species of each element for nanomaterial biosynthesis at varying levels of reduction potential (Eh) and pH. Based on the Pourbaix diagram analyses, the initial pH of the reaction was changed from 6.5 to 7.5, resulting in the biosynthesis of various crystalline nanomaterials that were previously amorphous or not synthesized. This strategy was extended to biosynthesize multi-element nanomaterials. Various single and multi-element nanomaterials biosynthesized in this research can potentially serve as new and novel nanomaterials for industrial applications such as catalysts, chemical sensors, biosensors, bioimaging, drug delivery, and cancer therapy. A research group consisting of PhD candidate Yoojin Choi, Associate Professor Doh Chang Lee, and Distinguished Professor Sang Yup Lee of the Department of Chemical and Biomolecular Engineering at KAIST and Associate Professor Tae Jung Park of the Department of Chemistry at Chung-Ang University reported the synthesis. This study, entitled “Recombinant Escherichia coli as a biofactory for various single- and multi-element nanomaterials,” was published online in the Proceedings of the National Academy of Sciences of the United States of America (PNAS) on May 21. A recent successful biosynthesis of nanomaterials under mild conditions without requiring physical and chemical treatments has triggered the exploration of the full biosynthesis capacity of a biological system for producing a diverse range of nanomaterials as well as for understanding biosynthesis mechanisms for crystalline versus amorphous nanomaterials. There has been increased interest in synthesizing various nanomaterials that have not yet been synthesized for various applications including semiconducting materials, enhanced solar cells, biomedical materials, and many others. This research reports the construction of a recombinant E. coli strain that co-expresses metallothionein, a metal binding protein, and phytochelatin synthase that synthesizes the metal-binding peptide phytochelatin for the biosynthesis of various nanomaterials. Subsequently, an E. coli strain was engineered to produce a diverse range of nanomaterials, including those never biosynthesized before, by using 35 individual elements from the periodic table and also by combining multi-elements. Distinguished Professor Lee said, “An environmentally-friendly and sustainable process is of much interest for producing nanomaterials by not only chemical and physical methods but biological synthesis. Moreover, there has been much attention paid to producing diverse and novel nanomaterials for new industrial applications. This is the first report to predict the biosynthesis of various nanomaterials, by far the largest number of various single- and multi-elements nanomaterials. The strategies used for nanomaterial biosynthesis in this research will be useful for further diversifying the portfolio of nanomaterials that can be manufactured.” Figure: The biosynthesis of diverse nanomaterials using recombinant E. coli. This schematic diagram shows the overall conceptualization of the biosynthesis of various single and multi-element nanomaterials using recombinant E. coli under incubation with corresponding elemental precursors. The 35 elements that were tested to biosynthesize nanomaterials are shown in black circles on the periodic table.
2018.05.23
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Platinum Catalyst Has Price Lowed and Durability Doubled
(Professor Cho in the Department of Materials Science and Engineering) Professor EunAe Cho in the Department of Materials Science and Engineering reported a fuel cell catalyst that shows 12 times higher performance and twice the durability than previously used platinum catalyst. Fuel cells, eco-friendly power generators, are said to be running air purifiers. A hydrogen vehicle powered by fuel cells can allegedly purify more than 98 percent of the particulate matter and ultrafine particles from the amount of air that 70 adults breathe. Despite this peculiarity, the high price of platinum, which is used as an electrode catalyst, remains a big challenge to accelerating commercialization. In addition, recently developed ‘nano-structured platinum catalysts’ have not yet commercialized due to its meager oxygen reduction reaction and durability in fuel cell. Addressing all those challenges, Professor Cho’s team reported a platinum catalyst costing 30 percent less but boasting 12 times higher performance. The research team, to this end, combined the platinum with nickel, then applied various metallic elements for making the most efficient performance. Among others, they found that the addition of gallium can modulate the oxygen intermediate binding energy, leading to enhanced catalytic activity of the oxygen reduction reaction. They made octahedron nanoparticle platinum-nickel alloy and could efficiently achieve 12-times high performance with the platinum catalyst by adding gallium to the surface of octahedron. Existing fuel cell catalysts have issues in practical fuel cell applications. However, Professor Cho’s team experimentally proved the high performance of the catalyst even in the fuel cell, and is expected to be practically applied to the existing procedure. First author JeongHoon Lim said their work demonstrates the gallium-added octahedral nanoparticles can be utilized as a highly active and durable oxygen reduction reaction catalyst in practical fuel cell applications. It will make it feasible for the mass production of the catalysts. Professor Cho also said, “Our study realized the two main goals: an affordable price and increased performance of fuel cells. We hope this will make a contribution to the market competitiveness of fuel cell electric vehicles.” This research was described in Nano Letters in April and was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP), the National Research Foundation (NRF), and the Agency for Defense Development (ADD). (Figure: HAADF STEM images with EDX analyses and line scanning profiles of (a) Ga-PtNi/C and (b) PtNi/C during the voltage-cycling tests. The composition changes of Ni, Pt, and Ga atoms in the nanoparticles were determined by EDX (inset in the EDX mapping results)).
2018.05.15
View 7638
Capillary Forces at Work for Lithium-Sulfur Batteries
Professor Do Kyung Kim from the KAIST Department of Materials Science and Engineering and his team succeeded in developing high-areal-capacity lithium sulfur batteries (Li-S batteries) by capturing polysulfide with carbon nanofibers. This research will provide new batteries to replace existing lithium rechargeable batteries, shifting the commercialization of related technologies ahead. Electrical vehicles and large-scale energy storage systems necessitate the development of batteries with high energy density and cost effectiveness, and Li-S batteries are known to be one of the promising alternatives to the predominant lithium ion batteries. With six times as much energy density, Li-S batteries theoretically thrust electric vehicle to twice the distance of lithium ion batteries. Therefore, they have been spotlighted as next-generation lithium rechargeable batteries because they can go up to 400km once charged. However, several issues make it challenging to readily commercialize Li-S batteries. The low electrical conductivity of sulfur, volumetric expansion and contraction of the battery during charge and discharge, and permanent damage of the electrode caused by the dissolution of the lithium polysulfide into the electrolyte – known as the “shuttle effect” – are three of the biggest obstacles to commercial-grade Li-S batteries. While there have been numerous attempts to curb, avoid, or alleviate these issues — such as the physical encapsulation of sulfur using various metal oxides or carbonaceous matrices — most of them entail utilizing zero-dimensional (0D) carbon materials. This encapsulation method has been somewhat effective in enhancing the electrical conductivity of sulfur while simultaneously tolerating some volumetric alterations and suppressing the shuttle effect. The downside of 0D carbon material-based encapsulation methods is their complicated synthetic processing and the limited mass loading of sulfur. With this in mind, the team set out to employ one-dimensional (1D) carbon materials instead. Unlike the 0D case, 1D carbon materials render a large surface area and a long-range conduction path for electrons and lithium ions. Being 1D also solves the undesirable high-contact resistance problem frequently encountered by 0D carbon material-based encapsulation. The key to developing the proposed material was to exploit the capillary force to decrease the energy associated with the dissolution of polysulfides. As such, carbon nanofibers (CNFs) were found to be suitable for high-areal-capacity lithium-sulfur batteries since capillary force acting between CNFs can take advantage of the high electrical conductivity with the suppressed dissolution of sulfides. The research findings show that sulfur was successfully contained in between the CNFs by wetting due to the capillary force without the need for complicated synthetic processing, as in the 0D case. The research results indicate that the sulfur contained per unit area (mg/cm2) is five times greater for the newly implemented method, which then enabled the lithium-sulfur battery to achieve an areal capacity of 7 mAh/cm2, which amounts to as much as at most seven times that of conventional lithium ion batteries. First author Jong Hyuk Yun stated that the unprecedented methods utilized in this study will help further and widen the progress of lithium batteries in general. Meanwhile, Professor Kim said, “This study brought us closer to commercial-grade high-capacity Li-S batteries, which are applicable for a wide variety of products, including electric vehicles, unmanned aerial vehicles (UAVs), and drones.” This research, led by PhD candidate Yun, was published in the 18th issue of this year’s Nano Letters. Figure 1. Electrochemical reaction leading to the containment of the sulfur within the carbon nanofiber and the corresponding specific capacity of the battery over a number of charge-discharge cycles Figure 2. SEM images of the first discharged electrode containing lithium sulfide at the junction between the nanofibers, and the first charged electrode Figure 3. carbon nanofiber effectively absorbing liquid based lithium polysulfide
2018.05.14
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New Material for Generating Energy-Efficient Spin Currents
(Professor Byong-Guk Park (left) and Professor Kab-Jin Kim) Magnetic random access memory (MRAM) is emerging as next-generation memory. It allows information to be kept even without an external power supply and its unique blend of high density and high speed operation is driving global semiconductor manufacturers to develop new versions continuously. A KAIST team, led by Professor Byong-Guk Park in the Department of Materials Science and Engineering and Professor Kab-Jin Kim in the Department of Physics, recently has developed a new material which enables the efficient generation of a spin current, the core part of operating MRAM. This new material consisting of ferromagnet-transition metal bilayers can randomly control the direction of the generated spin current unlike the existing ones. They also described a mechanism for spin-current generation at the interface between the bottom ferromagnetic layer and the non-magnetic spacer layer, which gives torques on the top magnetic layer that are consistent with the measured magnetization dependence. When applying this to spin-orbit torque magnetic memory, it shows the increased efficiency of spin torque and generation of the spin current without an external magnetic field. High-speed operation, the distinct feature of spin-orbit torque-based MRAM that carries its non-volatility, can significantly reduce the standby power better than SRAM. This new material will expect to speed up the commercialization of MRAM. The research team said that this magnetic memory will further be applied to mobile, wearable, and IoT devices. This study, conducted in collaboration with Professor Kyung-Jin Lee from Korea University and Dr. Mark Stiles from the National Institute of Standards and Technology in the US, was featured in Nature Materials in March. The research was funded by the Creative Materials Discovery Program of the Ministry of Science and ICT. (Figure: Ferromagnet-transition metal bilayers which can randomly control the direction of the generated spin current)
2018.05.11
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Yoon Ki Hong Named 2018 Jeong Hun Cho Awardee
(From left: PhD candidate Seungkwan Baek from the Department of Aerospace Engineering, Dr. Yoon Ki Hong from ADD, PhD candidate Wonhee Choi from the School of Mechanical Engineering at Korea University, and Jaehun Lee from Kongju National University High School) Dr. Yoon Ki Hong from the Agency of Defense Development (ADD) was named the 2018 recipient of the Jong-Hoon Cho Award. The award recognizes outstanding young scientists in the field of aerospace engineering annually. The recipient of this award receives a 25 million KRW prize. The Award Committee said that Dr. Hong has achieved outstanding work in the field of aerospace engineering. In particular, he conducted research on designing an air heating device which is the crucial component for ground experimental equipment. It is required for testing and evaluating supersonic vehicles’ structural strength tests using technology cannot be imported. In cooperation with his colleagues, he succeeded in developing an air heating device, a feat that has only been accomplished by developed countries. He also verified its operational performance. Moreover, he received the best paper award from Korean Federation of Science and Minister of Defense Acquisition Program Administration’s Prize. The award was endowed by the family of the late PhD candidate Jeong Hun Cho, who died in a rocket lab accident in the Department of Aerospace Engineering in 2003. Cho was posthumously conferred an honorary doctorate degree. In Cho’s memory, his father established the ‘Jeong Hun Cho Award and Scholarship’. Since 2005, the scholarship annually selects three young scholars specializing in aerospace engineering from Cho’s alma maters of KAIST, Korea University, and Kongju National University High School. In addition to Dr. Hong, the Award Committee chose three students for scholarships: PhD candidate Seungkwan Baek from the Department of Aerospace Engineering, PhD candidate Wonhee Choi from the School of Mechanical Engineering at Korea University, and Jaehun Lee from Kongju National University High School.
2018.05.11
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The First Recipient of the KPS Award in Plasma Physics
( Research Professor Sanghoo Park) Research Professor Sanghoo Park received the Young Researcher Award in Plasma Physics during the Korean Physical Society (KPS)’s Spring Meeting from April 25 to 27. He is a KAIST graduate with a PhD in Physics and currently holds the position of research professor in the Department of Nuclear and Quantum Engineering. The Young Researcher Award in Plasma Physics is given to a specialist in plasma who has the potential to make a contribution to plasma and accelerator physics in Korea. Professor Park has gained recognition for his work, including awards, publications in 24 journals, and 12 technical patent registrations of plasma, which led to his selection as the recipient of this award. He is now conducting a leading role in this field nationally and internationally by delving into the study of partially-ionized plasma. Professor Park said, “It is my great honor to become the first recipient of the Young Researcher Award in Plasma Physics. I will continue to engage in research to develop the field of plasma in Korea.”
2018.05.08
View 6765
Park Chosen for Principality of Monaco/ITER Postdoctoral Fellowship
(Jaesun Park in the Integrated Master's and Doctoral Degree Program ) Jaesun Park from the Department of Physics, was selected as a Principality of Monaco/ITER Postdoctoral Fellowship recipient. This program was established by the Principality of Monaco and an international organization, ITER, in January 2008 to support postdoctoral researchers who will be working for ITER. It is a relatively competitive program because it chooses only five people every two years. The selected postdoctoral researchers will be working for ITER for two years while conducting research projects with outstanding researchers in the field of nuclear fusion. ITER, one of the most ambitious energy projects, was launched in 1985 with the purpose of carrying out joint research on nuclear fusion energy. Currently, about 800 people are working for this organization. Seven ITER member countries (i.e. Korea, the European Union, the United States, China, Japan, Russia, and India) are sharing the expenses and engaging in mega-scale science projects. Korea shares 9.1% (20 billion Euro) of the total construction costs of ITER experimental devices. Park will begin his duties in early 2019.
2018.05.04
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Professor Hee-Sung Park Named Scientist of May
(Professor Hee-Sung Park) Professor Hee-Sung Park from the Department of Chemistry was named ‘Scientist of May’ sponsored by the Ministry of Science and ICT and the National Research Foundation of Korea. Professor Park was honored in recognition of his developing a tool to engineer designer proteins via diverse chemical modifications. This approach provides a novel platform for investigating numerous diseases such as cancer and dementia. His research focuses on the production of synthetic proteins and the generation of diverse protein functions as well as the designing and engineering of new translation machinery for genetic code expansion, and the application of synthetic biology techniques for basic cell biology and applied medical science. Post-translational modifications (PTMs) are constantly taking place during or after protein biosynthesis. PTMs play a vital role in expanding protein functional diversity and, as a result, critically affect numerous biological processes. Abnormal PTMs have been known to trigger various diseases including cancer and dementia. Therefore, this technology enables proteins to reproduce with specific modifications at selected residues and will significantly help establish experimental strategies to investigate fundamental biological mechanisms including the development of targeted cancer therapies. Professor Park also received 10 million KRW in prize money.
2018.05.04
View 10161
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