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Phage resistant Escherichia coli strains developed to reduce fermentation failure
A genome engineering-based systematic strategy for developing phage resistant Escherichia coli strains has been successfully developed through the collaborative efforts of a team led by Professor Sang Yup Lee, Professor Shi Chen, and Professor Lianrong Wang. This study by Xuan Zou et al. was published in Nature Communications in August 2022 and featured in Nature Communications Editors’ Highlights. The collaboration by the School of Pharmaceutical Sciences at Wuhan University, the First Affiliated Hospital of Shenzhen University, and the KAIST Department of Chemical and Biomolecular Engineering has made an important advance in the metabolic engineering and fermentation industry as it solves a big problem of phage infection causing fermentation failure. Systems metabolic engineering is a highly interdisciplinary field that has made the development of microbial cell factories to produce various bioproducts including chemicals, fuels, and materials possible in a sustainable and environmentally friendly way, mitigating the impact of worldwide resource depletion and climate change. Escherichia coli is one of the most important chassis microbial strains, given its wide applications in the bio-based production of a diverse range of chemicals and materials. With the development of tools and strategies for systems metabolic engineering using E. coli, a highly optimized and well-characterized cell factory will play a crucial role in converting cheap and readily available raw materials into products of great economic and industrial value. However, the consistent problem of phage contamination in fermentation imposes a devastating impact on host cells and threatens the productivity of bacterial bioprocesses in biotechnology facilities, which can lead to widespread fermentation failure and immeasurable economic loss. Host-controlled defense systems can be developed into effective genetic engineering solutions to address bacteriophage contamination in industrial-scale fermentation; however, most of the resistance mechanisms only narrowly restrict phages and their effect on phage contamination will be limited. There have been attempts to develop diverse abilities/systems for environmental adaptation or antiviral defense. The team’s collaborative efforts developed a new type II single-stranded DNA phosphorothioation (Ssp) defense system derived from E. coli 3234/A, which can be used in multiple industrial E. coli strains (e.g., E. coli K-12, B and W) to provide broad protection against various types of dsDNA coliphages. Furthermore, they developed a systematic genome engineering strategy involving the simultaneous genomic integration of the Ssp defense module and mutations in components that are essential to the phage life cycle. This strategy can be used to transform E. coli hosts that are highly susceptible to phage attack into strains with powerful restriction effects on the tested bacteriophages. This endows hosts with strong resistance against a wide spectrum of phage infections without affecting bacterial growth and normal physiological function. More importantly, the resulting engineered phage-resistant strains maintained the capabilities of producing the desired chemicals and recombinant proteins even under high levels of phage cocktail challenge, which provides crucial protection against phage attacks. This is a major step forward, as it provides a systematic solution for engineering phage-resistant bacterial strains, especially industrial bioproduction strains, to protect cells from a wide range of bacteriophages. Considering the functionality of this engineering strategy with diverse E. coli strains, the strategy reported in this study can be widely extended to other bacterial species and industrial applications, which will be of great interest to researchers in academia and industry alike. Fig. A schematic model of the systematic strategy for engineering phage-sensitive industrial E. coli strains into strains with broad antiphage activities. Through the simultaneous genomic integration of a DNA phosphorothioation-based Ssp defense module and mutations of components essential for the phage life cycle, the engineered E. coli strains show strong resistance against diverse phages tested and maintain the capabilities of producing example recombinant proteins, even under high levels of phage cocktail challenge.
Professor Il-Doo Kim Receives the Science Minister’s Award
Professor Il-Doo Kim from the Department of Materials Science and Engineering received the Science and ICT Minister’s Award in recognition of his commercialization and technology transfer achievements during the Day of IP celebration. Professor Kim, who has made over 222 patents application and registration home and abroad, has advanced toxic gas detection and breath gas sensor technology by arraying nanosensor fibers. His technological advances in micro-electro-mechanical systems (MEMS) helped to advance the commercialization of the MEMS-related sensor and improve its overall competitiveness. He founded the Il-Doo Kim Research Center in 2019 and focuses on the commercialization of nanofiber manufacturing through electrospinning and highly efficient nanofiber filters. For instance, he succeeded in manufacturing a nano-filter recyclable mask that maintains excellent filtering efficiency even after hand washing through the development of proprietary technology that aligns nanofibers with a diameter of 100~500 nanometers in orthogonal or unidirectional directions. Professor Kim also serves as an associate editor at ACS Nano. He said, “The importance of IP goes without saying. I look forward to the registration and application of more KAIST patents leading to commercialization, paving the way for national technological competitiveness.”
Sulfur-Containing Polymer Generates High Refractive Index and Transparency
Transparent polymer thin film with refractive index exceeding 1.9 to serve as new platform materials for high-end optical device applications Researchers reported a novel technology enhancing the high transparency of refractive polymer film via a one-step vapor deposition process. The sulfur-containing polymer (SCP) film produced by Professor Sung Gap Im’s research team at KAIST’s Department of Chemical and Biomolecular Engineering has exhibited excellent environmental stability and chemical resistance, which is highly desirable for its application in long-term optical device applications. The high refractive index exceeding 1.9 while being fully transparent in the entire visible range will help expand the applications of optoelectronic devices. The refractive index is a ratio of the speed of light in a vacuum to the phase velocity of light in a material, used as a measure of how much the path of light is bent when passing through a material. With the miniaturization of various optical parts used in mobile devices and imaging, demand has been rapidly growing for high refractive index transparent materials that induce more light refraction with a thin film. As polymers have outstanding physical properties and can be easily processed in various forms, they are widely used in a variety of applications such as plastic eyeglass lenses. However, there have been very few polymers developed so far with a refractive index exceeding 1.75, and existing high refractive index polymers require costly materials and complicated manufacturing processes. Above all, core technologies for producing such materials have been dominated by Japanese companies, causing long-standing challenges for Korean manufacturers. Securing a stable supply of high-performance, high refractive index materials is crucial for the production of optical devices that are lighter, more affordable, and can be freely manipulated. The research team successfully manufactured a whole new polymer thin film material with a refractive index exceeding 1.9 and excellent transparency, using just a one-step chemical reaction. The SCP film showed outstanding optical transparency across the entire visible light region, presumably due to the uniformly dispersed, short-segment polysulfide chains, which is a distinct feature unachievable in polymerizations with molten sulfur. The team focused on the fact that elemental sulfur is easily sublimated to produce a high refractive index polymer by polymerizing the vaporized sulfur with a variety of substances. This method suppresses the formation of overly long S-S chains while achieving outstanding thermal stability in high sulfur concentrations and generating transparent non-crystalline polymers across the entire visible spectrum. Due to the characteristics of the vapor phase process, the high refractive index thin film can be coated not just on silicon wafers or glass substrates, but on a wide range of textured surfaces as well. We believe this thin film polymer is the first to have achieved an ultrahigh refractive index exceeding 1.9. Professor Im said, “This high-performance polymer film can be created in a simple one-step manner, which is highly advantageous in the synthesis of SCPs with a high refractive index. This will serve as a platform material for future high-end optical device applications.” This study, in collaboration with research teams from Seoul National University and Kyung Hee University, was reported in Science Advances. (Title: One-Step Vapor-Phase Synthesis of Transparent High-Refractive Index Sulfur-Containing Polymers） This research was supported by the Ministry of Science and ICT’s Global Frontier Project (Center for Advanced Soft-Electronics), Leading Research Center Support Program (Wearable Platform Materials Technology Center), and Basic Science Research Program (Advanced Research Project).
From Dark to Light in a Flash: Smart Film Lets Windows Switch Autonomously
Researchers have developed a new easy-to-use smart optical film technology that allows smart window devices to autonomously switch between transparent and opaque states in response to the surrounding light conditions. The proposed 3D hybrid nanocomposite film with a highly periodic network structure has empirically demonstrated its high speed and performance, enabling the smart window to quantify and self-regulate its high-contrast optical transmittance. As a proof of concept, a mobile-app-enabled smart window device for Internet of Things (IoT) applications has been realized using the proposed smart optical film with successful expansion to the 3-by-3-inch scale. This energy-efficient and cost-effective technology holds great promise for future use in various applications that require active optical transmission modulation. Flexible optical transmission modulation technologies for smart applications including privacy-protection windows, zero-energy buildings, and beam projection screens have been in the spotlight in recent years. Conventional technologies that used external stimuli such as electricity, heat, or light to modulate optical transmission had only limited applications due to their slow response speeds, unnecessary color switching, and low durability, stability, and safety. The optical transmission modulation contrast achieved by controlling the light scattering interfaces on non-periodic 2D surface structures that often have low optical density such as cracks, wrinkles, and pillars is also generally low. In addition, since the light scattering interfaces are exposed and not subject to any passivation, they can be vulnerable to external damage and may lose optical transmission modulation functions. Furthermore, in-plane scattering interfaces that randomly exist on the surface make large-area modulation with uniformity difficult. Inspired by these limitations, a KAIST research team led by Professor Seokwoo Jeon from the Department of Materials Science and Engineering and Professor Jung-Wuk Hong of the Civil and Environmental Engineering Department used proximity-field nanopatterning (PnP) technology that effectively produces highly periodic 3D hybrid nanostructures, and an atomic layer deposition (ALD) technique that allows the precise control of oxide deposition and the high-quality fabrication of semiconductor devices. The team then successfully produced a large-scale smart optical film with a size of 3 by 3 inches in which ultrathin alumina nanoshells are inserted between the elastomers in a periodic 3D nanonetwork. This “mechano-responsive” 3D hybrid nanocomposite film with a highly periodic network structure is the largest smart optical transmission modulation film that exists. The film has been shown to have state-of-the-art optical transmission modulation of up to 74% at visible wavelengths from 90% initial transmission to 16% in the scattering state under strain. Its durability and stability were proved by more than 10,000 tests of harsh mechanical deformation including stretching, releasing, bending, and being placed under high temperatures of up to 70°C. When this film was used, the transmittance of the smart window device was adjusted promptly and automatically within one second in response to the surrounding light conditions. Through these experiments, the underlying physics of optical scattering phenomena occurring in the heterogeneous interfaces were identified. Their findings were reported in the online edition of Advanced Science on April 26. KAIST Professor Jong-Hwa Shin’s group and Professor Young-Seok Shim at Silla University also collaborated on this project. Donghwi Cho, a PhD candidate in materials science and engineering at KAIST and co-lead author of the study, said, “Our smart optical film technology can better control high-contrast optical transmittance by relatively simple operating principles and with low energy consumption and costs.” “When this technology is applied by simply attaching the film to a conventional smart window glass surface without replacing the existing window system, fast switching and uniform tinting are possible while also securing durability, stability, and safety. In addition, its wide range of applications for stretchable or rollable devices such as wall-type displays for a beam projection screen will also fulfill aesthetic needs,” he added. This work was supported by the National Research Foundation of Korea (NRF), and the Korean Ministries of Science, ICT and Future Planning (MSIP), and Science and ICT (MSIT). Publication: Cho, D, et al. (2020) ‘High-Contrast Optical Modulation from Strain-Indicated Nanogaps at 3D Heterogeneous Interfaces’ Advanced Science, 1903708. Available online at https://doi.org/10.1002/advs.201903708 Profile: Seokwoo Jeon, PhD Professor email@example.com https://fdml.kaist.ac.kr/ Flexible Device and Metamaterials Lab (FDML) Department of Materials Science and Engineering (MSE) Korea Advanced Institute of Science and Technology (KAIST) https://www.kaist.ac.krDaejeon 34141, Korea Profile: Jung-Wuk Hong, PhD Associate Professor firstname.lastname@example.org http://aaml.kaist.ac.kr Advanced Applied Mechanics Laboratory (AAML) Department of Civil and Environmental Engineering KAIST Profile: Donghwi Cho PhD Candidate email@example.comFDML, MSE, KAIST Profile: Young-Seok Shim, PhD Assistant Professor firstname.lastname@example.org Division of Materials Science and Engineering Silla University https://www.silla.ac.kr Busan 46958, Korea (END)
Antivirus Industry the Centerpiece of New Deal R&D Initiatives
- KAIST launches post-COVID-19 R&D initiatives for smart mobile medical systems. - KAIST will make the antivirus industry the centerpiece of what it is touting as the KAIST New Deal R&D initiative, which will drive new growth engines for preparing for the post-coronavirus era. According to the new initiative, KAIST will concentrate on creating antivirus technologies, infectious disease-related big data management, and non-contact services platforms as key future R&D projects. President Sung-Chul Shin launched the COVID-19 R&D Initiative task force last month, composed of more than 50 professors from the Graduate School of Medical Science and Engineering, the Department of Biological Sciences, the College of Engineering, and the Department of Industrial Design. The task force came up with key research agendas that will promote smart mobile medical systems in the years ahead. “We will devote all of our R&D capacities to pursue a smart healthcare society,” said President Shin. “Our competitiveness in the fields of AI, ICT, materials, and bio-technology holds significant potential for building a healthy society powered by smart medical systems in Korea,” he added. The smart medical systems focus mainly on building an Epidemic Mitigating Mobile Module (EMMM). The EMMM will manage epidemics via the three phases of prevention, emergency response, and treatment, with the development of each phase’s technological modules. The EMMM will also build an AI big data platform to assist with clinical applications and epidemic management. Technologies applicable for the prevention phase include developing recyclable antivirus masks, plasma virus sterilizers, and smart breathable protective gowns. KAIST researchers will also focus on developing diagnosis modules that will identify epidemics more quickly and accurately. Most significantly, KAIST aims to develop technologies for anti-infection medical services such as the transformable negative pressure ambulance module and negative pressure room, which are specially developed for respiratory infections. The new R&D initiatives will center on virus therapies and treatments, specifically pushing forward vaccine and robotics studies. As caring robots and delivery robots will become common as main caregivers via noncontact services, research focusing on robotics will be significantly enhanced. Even before launching the new R&D initiatives, researchers have started to present new technologies to help address the pandemic. Professor Il-Doo Kim’s team in the Department of Materials Science and Engineering developed a washable nano-fiber filtered face mask that is preparing for commercialization. GPS tracking of infections has expanded comprehensively to detect both indoor and outdoor activities of infected patients. Professor Dong-Soo Han from the School of Computing developed Wi-Fi positioning software built into mobile phones that can trace both activities and is now preparing to roll it out. Virologist Ui-Cheol Shin from the Graduate School of Medical Science and Engineering is carrying out research on a universal T-cell vaccine that can block the Betacoronaviruses. It is reported that that new epidemics such as SARS, MERS, and COVID-19 carry Betacoronaviruses. Research teams in the Graduate School of AI are conducting various research projects on building prediction models for outbreaks and spreads using big data. (END)
Highly Uniform and Low Hysteresis Pressure Sensor to Increase Practical Applicability
< Professor Steve Park (left) and the First Author Mr. Jinwon Oh (right) > Researchers have designed a flexible pressure sensor that is expected to have a much wider applicability. A KAIST research team fabricated a piezoresistive pressure sensor of high uniformity with low hysteresis by chemically grafting a conductive polymer onto a porous elastomer template. The team discovered that the uniformity of pore size and shape is directly related to the uniformity of the sensor. The team noted that by increasing pore size and shape variability, the variability of the sensor characteristics also increases. Researchers led by Professor Steve Park from the Department of Materials Science and Engineering confirmed that compared to other sensors composed of randomly sized and shaped pores, which had a coefficient of variation in relative resistance change of 69.65%, their newly developed sensor exhibited much higher uniformity with a coefficient of variation of 2.43%. This study was reported in Small as the cover article on August 16. Flexible pressure sensors have been actively researched and widely applied in electronic equipment such as touch screens, robots, wearable healthcare devices, electronic skin, and human-machine interfaces. In particular, piezoresistive pressure sensors based on elastomer‐conductive material composites hold significant potential due to their many advantages including a simple and low-cost fabrication process. Various research results have been reported for ways to improve the performance of piezoresistive pressure sensors, most of which have been focused on increasing the sensitivity. Despite its significance, maximizing the sensitivity of composite-based piezoresistive pressure sensors is not necessary for many applications. On the other hand, sensor-to-sensor uniformity and hysteresis are two properties that are of critical importance to realize any application. The importance of sensor-to-sensor uniformity is obvious. If the sensors manufactured under the same conditions have different properties, measurement reliability is compromised, and therefore the sensor cannot be used in a practical setting. In addition, low hysteresis is also essential for improved measurement reliability. Hysteresis is a phenomenon in which the electrical readings differ depending on how fast or slow the sensor is being pressed, whether pressure is being released or applied, and how long and to what degree the sensor has been pressed. When a sensor has high hysteresis, the electrical readings will differ even under the same pressure, making the measurements unreliable. Researchers said they observed a negligible hysteresis degree which was only 2%. This was attributed to the strong chemical bonding between the conductive polymer and the elastomer template, which prevents their relative sliding and displacement, and the porosity of the elastomer that enhances elastic behavior. “This technology brings forth insight into how to address the two critical issues in pressure sensors: uniformity and hysteresis. We expect our technology to play an important role in increasing practical applications and the commercialization of pressure sensors in the near future,” said Professor Park. This work was conducted as part of the KAIST‐funded Global Singularity Research Program for 2019, and also supported by the KUSTAR‐KAIST Institute. Figure 1. Image of a porous elastomer template with uniform pore size and shape (left), Graph showing high uniformity in the sensors’ performance (right). Figure 2. Hysteresis loops of the sensor at different pressure levels (left), and after a different number of cycles (right). Figure 3. The cover page of Small Journal, Volume 15, Issue 33. Publication: Jinwon Oh, Jin‐Oh Kim, Yunjoo Kim, Han Byul Choi, Jun Chang Yang, Serin Lee, Mikhail Pyatykh, Jung Kim, Joo Yong Sim, and Steve Park. 2019. Highly Uniform and Low Hysteresis Piezoresistive Pressure Sensors Based on Chemical Grafting of Polypyrrole on Elastomer Template with Uniform Pore Size. Small. Wiley-VCH Verlag GmbH & Co. KgaA, Weinheim, Germany, Volume No. 15, Issue No. 33, Full Paper No. 201901744, 8 pages. https://doi.org/10.1002/smll.201901744 Profile: Prof. Steve Park, MS, PhD email@example.com http://steveparklab.kaist.ac.kr/ Assistant Professor Organic and Nano Electronics Laboratory Department of Materials Science and Engineering Korea Advanced Institute of Science and Technology (KAIST) http://kaist.ac.kr Daejeon 34141, Korea Profile: Mr. Jinwon Oh, MS firstname.lastname@example.org http://steveparklab.kaist.ac.kr/ Researcher Organic and Nano Electronics Laboratory Department of Materials Science and Engineering Korea Advanced Institute of Science and Technology (KAIST) http://kaist.ac.kr Daejeon 34141, Korea Profile: Prof. Jung Kim, MS, PhD email@example.com http://medev.kaist.ac.kr/ Professor Biorobotics Laboratory Department of Mechanical Engineering Korea Advanced Institute of Science and Technology (KAIST) http://kaist.ac.kr Daejeon 34141, Korea Profile: Joo Yong Sim, PhD firstname.lastname@example.org Researcher Bio-Medical IT Convergence Research Department Electronics and Telecommunications Research Institute (ETRI) https://www.etri.re.krDaejeon 34129, Korea (END)
Micropatch Made of DNA
Researchers reported the fabrication of microstructure arrays of DNA materials using topographic control. This method provides a platform for forming multiscale hierarchical orientations of soft and biomaterials using a process of simple shearing and controlled evaporation on a patterned substrate. This approach enables the potential of patterning applications using DNA or other anisotropic biomaterials. DNA is one of the most abundant biomaterials found in all living organisms in nature. It has unique characteristics of fine feature size and liquid crystalline phase, enabling to create various kinds of microstructure DNA arrays. Based on these characteristics, DNA has been used as a building block for “origami” and textile art at the nanometer scale. A KAIST research team led by Professors Dong Ki Yoon and Hyungsoo Kim fabricated a DNA-based micropatch using the “coffee ring effect” and its multi-angle control technology, which was published online in Nature Communications on June 7. The research team used cheap DNA material extracted from salmon to realize the micropatch structure with well-aligned knit or ice cream cone shapes. When the DNA material in an aqueous solution is rubbed between two solid substrates while water is evaporating, DNA chains are unidirectionally aligned to make a thin film such as in LCD display devices. The DNA chains can make more complex microstructures such as knit or a texture with ice cream cone shapes when the same procedure is carried out in topographical patterns like microposts (Figure 1). This can be applied to make metamaterials by mixing with functionalized gold nanorods to show plasmonic color. Plasmon resonance is a phenomenon in which electrons vibrate uniformly on the surface of a substrate made of metal, reacting only to light that matches a specific energy to enhance the clarity and expression of colors. For this, the most important factor is the orientation in which the gold nanorods align. That is, when the rods are aligned side by side in one direction, the optical and electrical characteristics are maximized. The research team focused on this point and made the DNA micropatch as a frame to orient the gold nanorods in a unique shape and fabricated a plasmonic color film (Figure 2). Professor Yoon said this study is meaningful in that it deals with the evaporation phenomenon, which has not been studied much in the field of polymers and biopolymers in terms of basic science. He explained, “This will also help maximize the efficiency of polymeric materials that can be orientated in coating, 2D, and 3D printing applications. Furthermore, DNA that exists infinitely in nature can be expected to have industrial application value as a new material since it can easily form complexes with other materials as described in this study.” (Figure 1. The DNA micropatch using topographic control. (a) The experimental scheme. (b) Enlarged image of (e). (c-e) Different micropatches made of DNA using different shearing directions.) (Figure 2. The knit-like structures made of DNA-gold nanorod complex. (a,b) Optical and polarized optical microscopy images. (c-f) Plasmonic colors reflected from aligned DNA-gold nanorod complex depending on the sample rotation.)
Hyosung R&DB Labs to Teach Special Class on High Molecule Chemistry for the Fall Semester
The Department of Chemistry in collaboration with the Hyosung Group’s R&DB Labs will open a ‘special class on high molecule chemistry’ for Masters and Ph.D. candidates. The class, led by researchers at Hyosung’s R&D think tank, will provide the latest market and technology trends in the molecule chemical industry during the fall semester. Hyosung joined this special industry program in an effort to enhance students’ hands-on understanding of new technologies that will emerge in the global market. During the semester, Hyosung plans to present the technology portfolios on their brand new materials of TAC film, membrane, and carbon fiber as well as the existing products leading the world in market share such as spandex, tire cords. Hyosung plans to recruit students who previously took courses led by Hyosung researchers. President Tu-Won Chang of Hyosung R&DB said, “This program is designed to foster highly qualified R&D personnel especially catering to our company’s needs and market demands. We will continue to share our company’s market analysis and R&D know-how with outstanding universities.
KAIST Develops Transparent Oxide Thin-Film Transistors
With the advent of the Internet of Things (IoT) era, strong demand has grown for wearable and transparent displays that can be applied to various fields such as augmented reality (AR) and skin-like thin flexible devices. However, previous flexible transparent displays have posed real challenges to overcome, which are, among others, poor transparency and low electrical performance. To improve the transparency and performance, past research efforts have tried to use inorganic-based electronics, but the fundamental thermal instabilities of plastic substrates have hampered the high temperature process, an essential step necessary for the fabrication of high performance electronic devices. As a solution to this problem, a research team led by Professors Keon Jae Lee and Sang-Hee Ko Park of the Department of Materials Science and Engineering at the KAIST has developed ultrathin and transparent oxide thin-film transistors (TFT) for an active-matrix backplane of a flexible display by using the inorganic-based laser lift-off (ILLO) method. Professor Lee’s team previously demonstrated the ILLO technology for energy-harvesting (Advanced Materials, February 12, 2014) and flexible memory (Advanced Materials, September 8, 2014) devices. The research team fabricated a high-performance oxide TFT array on top of a sacrificial laser-reactive substrate. After laser irradiation from the backside of the substrate, only the oxide TFT arrays were separated from the sacrificial substrate as a result of reaction between laser and laser-reactive layer, and then subsequently transferred onto ultrathin plastics ( thickness). Finally, the transferred ultrathin-oxide driving circuit for the flexible display was attached conformally to the surface of human skin to demonstrate the possibility of the wearable application. The attached oxide TFTs showed high optical transparency of 83% and mobility of even under several cycles of severe bending tests. Professor Lee said, “By using our ILLO process, the technological barriers for high performance transparent flexible displays have been overcome at a relatively low cost by removing expensive polyimide substrates. Moreover, the high-quality oxide semiconductor can be easily transferred onto skin-like or any flexible substrate for wearable application.” These research results, entitled “Skin-Like Oxide Thin-Film Transistors for Transparent Displays,” (http://onlinelibrary.wiley.com/doi/10.1002/adfm.201601296/abstract) were the lead article published in the July 2016 online issue of Wiley’s Advanced Functional Materials. ### References  Advanced Materials, February 12, 2014, Highly-efficient, Flexible Piezoelectric PZT Thin Film Nanogenerator on Plastic Substrates (http://onlinelibrary.wiley.com/doi/10.1002/adma.201305659/abstract)  Advanced Materials, September 8, 2014, Flexible Crossbar-structured Resistive Memory Arrays on Plastic Substartes via Inorganic-based Laser Lift-off (http://onlinelibrary.wiley.com/doi/10.1002/adma.201402472/abstract) Picture 1: A Schamatic Image of Ultrathin, Flexible, and Transparent Oxide Thin-film Transistors This image shows ultrathin, flexible, and transparent oxide thin-film transistors produced via the ILLO process. Picture 2: Application of Uultrathin, Flexible, and Transparent Oxide Thin-film Transistors This picture shows ultrathin, flexible, and transparent oxide thin-film transistors attached to a jumper sleeve and human skin.
A Technology Holding Company Establishes Two Companies Based on Technologies Developed at KAIST
Mirae Holdings is a technology holding company created by four science and technology universities, KAIST, DIGIST (Daegu Gyeongbuk Institute of Science and Technology), GIST (Gwangju Institute of Science and Technology), and UNIST (Ulsan National Institute of Science and Technology) in 2014 to commercialize the universities’ research achievements. The company identifies promising technologies for commercialization, makes business plans, establishes venture capitals, and invests in startup companies. Over the past year, Mirae Holdings has established two venture companies based on the technologies developed at KAIST. In September 2014, it founded Cresem Inc., a company used the anisotropic conductive film (ACF) bonding technology, which was developed by Professor Kyung-Wook Paik of the Material Science and Engineering Department at KAIST. Cresem provides a technology to bond electronic parts ultrasonically. The company is expected to have 860,000 USD worth of sales within the first year of its launching. Last June, Mirae Holdings created another company, Doctor Kitchen, with the technology developed by Professor Gwan-Su Yi of the Bio and Brain Engineering Department at KAIST. Doctor Kitchen supplies precooked food, which helps diabetic patients regulate their diet. The company offers a personalized diet plan to customers so that they can effectively manage their disease and monitor their blood sugar level efficiently. The Chief Executive Officer of Mirae Holdings, Young-Ho Kim, said, “We can assist KAIST researchers who aspire to create a company based on their research outcomes through various stages of startup services such as making business plans, securing venture capitals, and networking with existing businesses.” Young-Ho Kim (left in the picture), the Chief Executive Officer of Mirae Holdings, holds a certificate of company registration with Sang-Min Oh (right in the picture), the Chief Executive Officer of Cresem. Young-Ho Kim (left in the picture), the Chief Executive Officer of Mirae Holdings, holds a certificate of company registration with Jae-Yeun Park (right in the picture), the Chief Executive Officer of Dr. Kitchen.
Is it possible to identify rumors on SNS?
Rumors sporadically spread with people with fewer followers in the centerResearched over 100 rumors in the US from 2006 to 2009 Is it possible to filter information on SNS such as Twitter and Facebook? A research team led by Professor Mee-Young Cha from the Department of Cultural Technology Graduate School at KAIST, Professor Kyo-Min Jung of Seoul National University, Doctor Wei Chen and Yajun Wang of Microsoft Asia, has developed a technology that can accurately filter out information on Twitter to 90% accuracy. The research not only deduced a new mathematical model, network structure, and linguistic characteristics on rumors from SNS data, but is also expected to enhance the effort to make secure technology to regulate Internet rumors. The team analysed the characteristics of rumors in over 100 widespread cases in the US from 2006 to 2009 on Twitter. The team gathered data, which included a range of areas such as politics, IT, health and celebrity gossips, and their analysis could identify rumors to 90% accuracy. The filtering was more accurate in rumors that included slanders or insults. The research team identified three characteristics of the spread of rumors. Firstly, rumors spread continuously. Normal news spreads widely once and is mentioned rarely again on media, but rumors tend to continue for years. Secondly, rumors spread through sporadic participation of random users with no connections. Rumors start from people with fewer followers and spread to the more popular. This phenomenon is often observed in rumors concerning celebrities or politicians. Lastly, rumors have unique linguistic characteristics. Rumors frequently include words (such as “it may be true,” “although not certain, I think,” “although I cannot fully remember”) related to psychological processes that question, deny, or infer the reliability of the information. Professor Cha said, “This research deduced not only a statistical and mathematical model but also is an integrated research on social psychological theory on the characteristics of rumors that attract great attention from the society based on ample data.” The results were made public in IEEE International Conference on Data Mining last December in Texas, USA.
Observation of a water strider led to a new method of measuring properties of Nano films
Even the mechanical properties of Nano films of a few nanometers thick can be measured Posted online Nature Communications on the 3rd of October The joint research team of KAIST’s Department of Mechanical Engineering’s Professor Taek-Soo Kim and Doctor Seung-Min Hyun of the Nano mechanics laboratory of Korea Institute of Machinery and Materials has developed a new method to evaluate mechanical properties of Nano films using the characteristics of water surfaces. The research findings have been posted on the online edition of Nature Communications on the 3rd of October. The technology can obtain accurate results by directly measuring the mechanical properties such as the strength and elasticity of Nano films. Academia and the industry expect the simplicity of the technology to present a new paradigm in the evaluation of mechanical properties of Nano films. Evaluation of the mechanical properties of Nano films is essential not only in predicting the reliability of semiconductors and displays, but also in finding new phenomena in the Nano world. However, mechanical strength was difficult to test since the test demands the falling of objects to the ground to measure their strength, and nano films can easily break in the process. The research team observed insects such as water striders freely floating on the surface of the water. The team used the properties of water, large surface tension and low viscosity, to float a 55 nanometers (nm) gold Nano film to successfully measure its mechanical properties without damaging it. The technology could be used to measure the mechanical properties of not only various types of Nano films but also films only a few nm thick. Professor Taek-Soo Kim said, “We effectively performed an evaluation of the mechanical characteristics of Nano films, which was difficult in the past, by developing a new strength test using the properties of water.” He continued to say, “The team plans to discover the mechanical properties of 2D Nano films such as graphene that could not have been measured with the existing strength test methods.” The research by KAIST’s Department of Mechanical Engineering’s graduate student Jae-Han Kim (lead author) under the supervision of Professor Taek-Soo Kim and Doctor Seung-Min Hyun of Korea Institute of Machinery and Materials was sponsored by the National Research Foundation of Korea. Evaluation process of mechanical properties of Nano films by using the characteristics of water surfaces Dr Seung-Min Hyun, Jae-Han Kim, and Professor Taek-Soo Kim from left to right
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