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High-Speed Motion Core Technology for Magnetic Memory
(Professor Kab-Jin Kim of the Department of Physics)
A joint research team led by Professor Kab-Jin Kim of the Department of Physics, KAIST and Professor Kyung-Jin Lee at Korea University developed technology to dramatically enhance the speed of next generation domain wall-based magnetic memory. This research was published online in Nature Materials on September 25.
Currently-used memory materials, D-RAM and S-RAM, are fast but volatile, leading to memory loss when the power is switched off. Flash memory is non-volatile but slow, while hard disk drives (HDD) have greater storage but are high in energy usage and weak in physical shock tolerance.
To overcome the limitations of existing memory materials, ‘domain wall-based, magnetic memory’ is being researched. The core mechanism of domain wall magnetic memory is the movement of a domain wall by the current. Non-volatility is secured by using magnetic nanowires and the lack of mechanical rotation reduced power usage. This is a new form of high density, low power next-generation memory.
However, previous studies showed the speed limit of domain wall memory to be hundreds m/s at maximum due to the ‘Walker breakdown phenomenon’, which refers to velocity breakdown from the angular precession of a domain wall. Therefore, there was a need to develop core technology to remove the Walker breakdown phenomenon and increase the speed for the commercialization of domain wall memory.
Most domain wall memory studies used ferromagnetic bodies, which cannot overcome the Walker breakdown phenomenon. The team discovered that the use of ‘ferrimagnetic‘ GdFeCo at certain conditions could overcome the Walker breakdown phenomenon and using this mechanism they could increase domain wall speed to over 2Km/s at room temperature.
Domain wall memory is high-density, low-power, and non-volatile memory. The memory could be the leading next-generation memory with the addition of the high speed property discovered in this research.
Professor Kim said, “This research is significant in discovering a new physical phenomenon at the point at which the angular momentum of a ferrimagnetic body is 0 and it is expected to advance the implementation of next-generation memory in the future.”
This research was funded by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MSIP) (No. 2017R1C1B2009686, NRF-2016R1A5A1008184) and by the DGIST R&D Program of the Ministry of Science, ICT and Future Planning (17-BT-02).
(Figure 1. Concept Map of Domain Wall Memory Material using Ferrimagnetic Body)
(Figure 2. Scheme and Experimental Results of Domain Wall Speed Measurements)
2017.10.30 View 7636 -
Hanmaeum Education Corps Invites Multicultural Families
About 100 graduates from the Multicultural Mother Schools and their families visited the KAIST campus on October 29 at the invitation of the Hanmaeum Education Corps of KAIST. The Hanmanum Education Corps is a volunteering organization composed of KAIST faculty and students. Many retired KAIST faculties are also members of the corps. Byong Kyu Choi, an Emeritus Professor from the Department of Industrial and Systems Engineering, is the director of the corps and has been leading the event since 2015.
With the support of a KAIST educational volunteering organization called SEED(Social Education Embracing Diversity), this year’s event offered various activities including a treasure hunt and convergent science programs. Participants had the opportunity to experience KAIST’s educational environment and enjoyed the perfect autumn weather during outdoor activities with student volunteers.
Children enjoyed making illumination-music stickers with the KAIST students, even though it was tough to learn at first.
While the children engaged themselves in the science program, parents visited the chrysanthemum fair and some of KAIST’s cafeterias.
Hanmaeum Education Corps opened the Multicultural Mother Schools to support multicultural mothers so that they can have more interest in and help their children more with their education. Since its establishment in 2015, the Multicultural Mother Schools have been expanding throughout the country.
The corporation hopes that visiting a renowned university will encourage children from multicultural families to study hard in addition to offering self-enrichment opportunities through career exploration and science activities.
2017.10.30 View 4332 -
KAIST and KOICA Invited Dominican Republic Officials for Workshop
KAIST will host a two-week workshop for Dominican Republic officials and scholars in collaboration with KOICA (Korea International Cooperation Agency) beginning October 23 at KAIST.
The workshop aims to encourage academia-industry cooperation as one of the Projects for Human Resource Development for Science and Technology at KOICA. Dominican participants including the assistant minister of the Ministry of Higher Education, Science and Technology (MESCYT) and deans of engineering colleges at major universities will enjoy lectures from experts and visit enterprises known for excellent academia-industry collaboration.
According to the Center for Overseas Development, at which Professor WonJoon Kim in the School of Business and Technology Management at KAIST holds the position of director, the workshop is designed to develop human resources in the science and technology (S&T) area, share knowledge on research and development in the field of academia-industry cooperation, and help the participants acquire know-how for managing partnerships between related organizations and industries.
During the workshop, KAIST plans to transfer know-how and share knowledge on its academia-industry cooperation R&D system, in hopes that the workshop will help the Dominican Republic foster its manpower in higher education. The workshop organizers hope that the officers and scholars will be able to apply what they will learn for establishing and carrying out detailed action plans for academia-industry cooperation policies in an effective manner.
“This workshop provides an opportunity to learn about the development of S&T in Korea, academia-industry cooperation R&D, and fostering manpower in advanced S&T. Through the knowledge sharing, we can have a better understanding of academia-industry cooperation as well as education on advanced manpower,” said Pedro Antonio Eduardo, the assistant minister of MESCYT.
He added, “I hope that this workshop will further detailed cooperation between the two countries for Korean high-tech enterprises’ overseas expansion and advanced manpower education. The development model in Korea has many essential elements, so learning its engine for growth and polytechnic manpower education will help develop my country’s industry sector.”
The Project for Human Resource Development for Science and Technology is one of the official development assistance projects running from last year until 2019. It promotes R&D activities for S&T in the Dominican Republic, encouraging academia-industry cooperation by improving trainers in charge of advanced manpower education.
2017.10.30 View 6694 -
Distinguished Professor Lee Named International Fellow of the CAS
Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering at KAIST was awarded the title of distinguished professor and international fellow from the Chinese Academy of Sciences (CAS), and honorary professor from its affiliated organization the Tianjin Institute of Industrial Biotechnology (TIB).
The CAS recognized Distinguished Professor Lee for his significant contributions to biotechnology. He has made significant pioneering academic achievements in the area of systems metabolic engineering, which produces useful chemicals from microorganisms. Not only did he develop the first and best source technology in that field, but also came out with processes for the production of biofuel and environmentally-friendly chemicals.”
As a global leader in systems metabolic engineering, Distinguished Professor Lee has also been appointed as an honorary professor at Jiangnan University in Wuxi, China.
Distinguished Professor Lee was listed in the ‘Top 20 Translational Researchers of 2014’ selected by the renowned international journal Nature Biotechnology. Moreover, he was the first Asian recipient of the James E. Bailey Award in 2016 and Marvin J. Johnson Award in 2012, which are given to scholars in the field of biotechnology.
He is also one of 13 global scientists who are foreign members of the renowned academic societies the National Academy of Engineering and the National Academy of Sciences in the US. Furthermore, he received the ‘2017 Korea Best Scientist Award’ from the president of Korea in July. Finally, his founding field, systems metabolic engineering, was chosen as one of the ‘Top 10 Emerging Technologies of 2016’ by the World Economic Forum.
The Chinese Academy of Sciences, established in November 1949, is an academic organization that carries out research on basic sciences and natural sciences in China. It defined its science and technology system to include the fields of basic sciences, natural sciences, and high technology. While having a base in Beijing, its branch academies are located in 12 main cities along with 117 affiliates and 100 national key labs.
2017.10.26 View 9583 -
Development of a Highly-Accurate Computational Model of Human Metabolism
A research team from KAIST developed a computational framework that enables the reconstruction of a comprehensive computational model of human metabolism, which allows for an accurate prediction of personal metabolic features (or phenotypes).
Understanding personal metabolic phenotypes allows us to design effective therapeutic strategies for various chronic and infectious diseases. A human computational model called the genome-scale metabolic model (GEM) contains information on thousands of metabolic genes and their corresponding reactions and metabolites, and has played an important role in predicting metabolic phenotypes. Although several versions of human GEMs have been released, they had room for further development, especially as to incorporating biological information coming from a human genetics mechanism called “alternative splicing.” Alternative splicing is a genetic mechanism that allows a gene to give rise to multiple reactions, and is strongly associated with pathology.
To tackle this problem, Jae Yong Ryu (a Ph.D. student), Dr. Hyun Uk Kim (Research Fellow), and Distinguished Professor Sang Yup Lee, all from the Department of Chemical and Biomolecular Engineering at KAIST, developed a computational framework that systematically generates metabolic reactions, and adds them to the human GEM. The resulting human GEM was demonstrated to accurately predict metabolic phenotypes under varied environmental conditions. The research results were published online in Proceedings of the National Academy of Sciences (PNAS) on October 24, 2017, under the title “Framework and resource for more than 11,000 gene-transcript-protein-reaction associations in human metabolism.”
The research team first updated the biological contents of a previous version of the human GEM. The updated biological contents include metabolic genes and their corresponding metabolites and reactions. In particular, metabolic reactions catalyzed by already-known protein isoforms were additionally incorporated into the human GEM; protein isoforms are multiple variants of proteins generated from individual genes through the alternative splicing process. Each protein isoform is often responsible for the operation of a metabolic reaction. Although multiple protein isoforms generated from one gene can play different functions by having different sets of protein domains and/or subcellular localizations, such information was not properly considered in previous versions of human GEMs.
Upon the initial update of the human GEM, named Recon 2M.1, the research team subsequently implemented a computational framework that systematically generates information on Gene-Transcript-Protein-Reaction Associations (GeTPRA) in order to identify protein isoforms that were previously not identified. This framework was developed in this study. As a result of the implementation of the framework for GeTPRA, more than 11,000 GeTPRA were automatically predicted, and thoroughly validated. Additional metabolic reactions were then added to Recon 2M.1 based on the predicted GeTPRA for the previously uncharacterized protein isoforms; Recon 2M.1 was renamed Recon 2M.2 from this upgrade.
Finally, Recon 2M.2 was integrated with 446 sets of personal biological data (RNA-Seq data) in order to build patient-specific cancer models. These patient-specific cancer models were used to predict cancer metabolism activities and anticancer targets.
The development of a new version of human GEMs along with the computational framework for GeTPRA is expected to boost studies in fundamental human genetics and medicine. Model files of the human GEMs Recon 2M.1 and 2M.2, a full list of the GeTPRA and the source code for the computational framework to predict the GeTPRA are all available as part of the publication of this study.
Distinguished Professor Lee said, “The predicted GeTPRA from the computational framework is expected to serve as a guideline for future experiments on human genetics and biochemistry, whereas the resulting Recon 2M.2 can be used to predict drug targets for various human diseases.”
This work was supported by the Technology Development Program to Solve Climate Changes on Systems Metabolic Engineering for Biorefineries (NRF-2012M1A2A2026556 and NRF-2012M1A2A2026557) from the Ministry of Science and ICT through the National Research Foundation (NRF) of Korea.
(Figure 1:A scheme of Recon 2M.1 development and its use in reconstructing personal genome-scale metabolic models (GEMs). (A) A concept of alternative splicing of human genes and its use in Gene-Transcript-Protein-Reaction Associations (GeTPRA) of Recon 2M.1. (B) A procedure of systematic refinement of the Recon 2Q. Recon 2Q is one of the previously released human GEMs. Biochemically inconsistent reactions include unbalanced, artificial, blocked, and/or redundant reactions. Iterative manual curation was conducted while validating the Recon 2M.1. (C) Reconstruction of cancer patient-specific GEMs using Recon 2M.1 for further simulation studies. In this study, personal biological data (RNA-Seq data) were obtained from The Cancer Genome Atlas (TCGA; https://cancergenome.nih.gov/ ) across the ten cancer types.
(Figure 2: Computational framework for the systematic generation of Gene-Transcript-Protein-Reaction Associations (GeTPRA; red box in the flowchart). Peptide sequences of metabolic genes defined in Recon 2M.1 were retrieved from a database called Ensembl. EC numbers and subcellular localizations of all the protein isoforms of metabolic genes in Recon 2M.1 were predicted using software programs EFICAz2.5 and Wolf PSort, respectively. Information on the newly predicted GeTPRA was systematically incorporated into the Recon 2M.1, thereby resulting in Recon 2M.2.)
2017.10.25 View 8709 -
Professor Dai Gil Lee Recognized by the ICCS
Emeritus Professor Dai Gil Lee, from the School of Mechanical and Aerospace Engineering at KAIST, received a special achievement award from the 20th International Conference on Composite Structures (ICCS).
ICCS is a renowned conference in the field of applied composite structures, which highlights the practicality of composite structures. This year, the conference was held at the Conservatoire National des Arts et Métiers (CNAM), Paris, France from September 4 to 7. Approximately 650 papers were presented from 45 countries.
Especially, the conference honored Emeritus Professor Lee, who has been engaged in ICCS since 1993 and received best paper award twice. The ICCS recognized him for serving with distinction in science and technology in the fields of composite materials and structures. As a member of the Editorial Board for many years, he gave significant support to the journal Composite Structures. At the conference, he gave a special lecture titled ‘Lightweight Carbon Composite Proton Exchange Membrane Fuel Cells’.
Professor Lee said, “I will dedicate myself to innovate Vanadium Redox Flow Battery-ESS (VRFB) based on the research findings announced at the conference and related patents. I am hoping that these efforts will contribute to solving energy issues around the world.”
2017.10.19 View 6553 -
KAIST Partners with WEF to Prepare for the 4th Industrial Revolution
KAIST President Sung-Chul Shin and the Head of the World Economic Forum Center for the Fourth Industrial Revolution, Murat Sonmez, made a commitment to build cooperation in an active manner for addressing the ramifications of the Fourth Industrial Revolution.
The two signed an MOU to cooperate in research in related fields on October 13 after holding a roundtable discussion titled “The Future of Jobs and Inclusive Growth in Korea”. It is the first partnership that the WEF has sealed with an academic institution.The roundtable discussion brought together distinguished guests from politics, non-profit civic organizations, academia, and enterprises including Daejeon Mayor Seon-Taek Kwon, Doosan Group Vice Chairman Lee Hyun-Soon, and Korean Venture Business Association President Ahn Keon-Joon.
During the news conference, President Shin said, “This event means a lot because it explores ways in which inclusive growth and job creation can be realized in Korea. To move forward in the new age of the Fourth Industrial Revolution, every country needs to adopt appropriate new policies suitable for their specific market environments. KAIST will contribute to this process for Korea as well as for the global community.”
President Shin also said, “Korea has been a fast follower in previous industrial revolutions. Now, we have the momentum to seize the opportunities in the wake of this revolution. KAIST is dedicated to leading Korea into becoming a first mover in the Fourth Industrial Revolution by cooperating with the WEF.”
“Two decades later, we will live with considerable number of robots around us. It is possible that our societies in the future will consist of Homo sapiens and Robo sapiens. We need to create new jobs for Homo sapiens to prepare for a society that we will have to coexist with a new industrial tribe. Industries need continuing education to retrain workers for the ever evolving industrial landscape of the future,” President Shin emphasized.
Meanwhile, Sonmez pointed out that all stakeholders should participate in understanding the new industrial environment’s ramifications, saying “Societies, governments, public and private sectors, startups, and academia should co-design inclusive models through global efforts. Ethics and influences on the job market should also be taken into consideration.”
Sonmez said nine factors such as blockchains, internet of things, artificial intelligence, machine learning, cross-border data blow, drones, 3D printing, autonomous driving, the environment, and precision medicine will take center stage in the Fourth Industrial Revolution, In particular, he said that blockchains, which are a cybersecurity technology for online financial transactions, will bring even bigger changes than the ‘World Wide Web’ has done over the past three decades.
“To this end, we will have to work closely with major academic institutes. Through this partnership with KAIST, we will make the fruits of the new industrial environment benefit Koreans and Korean society,” Sonmez added.
2017.10.14 View 7559 -
KAIST-WEF Roundtable on Inclusive Growth and Job Creation
The World Economic Forum (WEF) will join KAIST in an effort to address sweeping global problems in the wake of the Fourth Industrial Revolution. The two will co-host a roundtable on ‘Shaping Korea’s Priorities for Inclusive Growth and Job Creation in the Fourth Industrial Revolution’ on October 13 at Lotte Hotel in Seoul.
The roundtable will bring together leaders from government, industry, universities, and non-profit civic organizations to have an in-depth discussion on a thought-provoking agenda of inclusive growth and job creation which scientific and technological changes will bring about. The event will provide a platform to explore practical collaboration and innovative strategies for better job creation and innovation ecosystems.
The two will also sign an MOU for collaboration between the Fourth Industrial Revolution Information Center (FIRIC) of KAIST and the WEF Center for the Fourth Industrial Revolution (C4IR).
President Sung-Chul Shin of KAIST and the Head of the WEF Center for the Fourth Industrial Revolution, Murat Sonmez, will lead the panel discussion titled ‘Inclusive Growth and the Fourth Industrial Revolution’ which will be attended by leaders from government, industry, and non-profit civic organizations.
At the breakout sessions, the topics will be “Future Jobs” and the “Creation of Innovation Ecosystems”. Additionally, a discussion on the “SME 4.0 Initiative”, which is a program pushed forward by KAIST in collaboration with local governments, will talk about job creation through innovation in small and medium-sized enterprises (SMEs). The WEF will introduce their two-year activities and research on the Fourth Industrial Revolution, which have great potential and a high possibility of successfully undergoing the revolution, to Korea.
Since WEF Executive Chairman Klaus Schwab brought up the topic of the Fourth Industrial Revolution, the WEF has been leading agenda topics and discussions on high-profile matters, including ‘technology-driven but human-centered inclusive growth’ in predicting the future of jobs.
The WEF is a nonprofit organization committed to addressing the world’s weightiest problems. It is best known for its annual meetings in Davos, Switzerland, which attracts leaders from around the world. KAIST has been participating in this summit since 2009. President Shin will also attend the upcoming Davos summit next January. Distinguished Professor Sang Yup Lee who heads the KAIST Institute and the FIRIC is the co-chair of the Global Council on Biotechnology and a member of the Global Future Council on the Fourth Industrial Revolution at the WEF.
Moreover, President Shin and Mr. Sonmez will explain the background of the roundtable and share the results of the sessions at a joint news conference.
2017.09.28 View 8895 -
Sangeun Oh Recognized as a 2017 Google Fellow
Sangeun Oh, a Ph.D. candidate in the School of Computing was selected as a Google PhD Fellow in 2017. He is one of 47 awardees of the Google PhD Fellowship in the world.
The Google PhD Fellowship awards students showing outstanding performance in the field of computer science and related research. Since being established in 2009, the program has provided various benefits, including scholarships worth $10,000 USD and one-to-one research discussion with mentors from Google.
His research work on a mobile system that allows interactions among various kinds of smart devices was recognized in the field of mobile computing. He developed a mobile platform that allows smart devices to share diverse functions, including logins, payments, and sensors. This technology provides numerous user experiences that existing mobile platforms could not offer. Through cross-device functionality sharing, users can utilize multiple smart devices in a more convenient manner. The research was presented at The Annual International Conference on Mobile Systems, Applications, and Services (MobiSys) of the Association for Computing Machinery in July, 2017.
Oh said, “I would like to express my gratitude to my advisor, the professors in the School of Computing, and my lab colleagues. I will devote myself to carrying out more research in order to contribute to society.”
His advisor, Insik Shin, a professor in the School of Computing said, “Being recognized as a Google PhD Fellow is an honor to both the student as well as KAIST. I strongly anticipate and believe that Oh will make the next step by carrying out good quality research.”
2017.09.27 View 10142 -
Photoacoustic Imaging and Photothermal Cancer Therapy Using BR Nanoparticles
(Professor Sangyong Jon and PhD Candidate Dong Yun Lee)
Sangyong Jon, a professor in the Department of Biological Sciences at KAIST, and his team developed combined photoacoustic imaging and photothermal therapy for cancer by using Bilirubin (BR) nanoparticles.
The research team applied the properties of a bile pigment called BR, which exerts potent antioxidant and anti-inflammatory effects, to this research.
The team expects this research, which shows high biocompatibility as well as outstanding photoacoustic imaging and photothermal therapy, to be an appropriate system in the field of treatment for cancer.
In the past, the research team developed a PEGylated bilirubin-based nanoparticle system by combining water-insoluble BR with water-soluble Polyethylene Glycol (PEG).
This technology facilitated BR exerting antioxidants yet prevented them from being accumulated in the body. Its efficiency and safety was identified in an animal disease model, for conditions such as inflammatory bowel disease, islet cell transportation, and asthma.
Differing from previous research methods, this research applied the different physicochemical properties of BR to cancer treatment.
When the causative agent of jaundice, yellow BR, is exposed to a certain wavelength of blue light, the agent becomes a photonic nanomaterial as it responses to the light. This light-responsive nanomaterial can be used to cure jaundice because it allows for active excretion in infants.
Secondly, the team identified that BR is a major component of black pigment gallstones which can be often found in gall bladders or bile ducts under certain pathological conditions. The findings show that BR forms black pigment gallstones without the role of an intermediate or cation, such as calcium and copper. The research team combined cisplatin, a platinum metal-based anticancer drug, with BR so that BR nanoparticles changed the solution color from yellow to purple.
The team also examined the possibility of cisplatin-chelated BR nanoparticles as a probe for photoacoustic images. They found that considerable photoacoustic activity was shown when it was exposed to near infrared light. In fact, the photoacoustic signal was increased significantly in tumors of animals with colorectal cancer when the nanoparticles were administered to it intravenously. The team expects a more accurate diagnosis of tumors through this technology.
Moreover, the team assessed the photothermal effects of cisplatin-chelated BR nanoparticles. The research showed that the temperature of tumors increased by 25 degrees Celsius within five minutes when they were exposed to near infrared light, due to the photothermal effect. After two weeks, their size was reduced compared to that of other groups, and sometimes the tumors were even necrotized.
Professor Jon said, “Existing substances have a low biocompatibility and limitation for clinical therapy because they are artificially oriented; therefore, they might have toxicity. I am hoping that these cisplatin-chelated BR-based nanoparticles will provide a new platform for preclinical, translational research and clinical adaptation of the photoacoustic imaging and photothermal therapy.”
The paper (Dong Yun Lee as a first author) was published online in the renowned journal in the field of applied chemistry, Angewandte Chemi International Edition, on September 4. This research was sponsored by the National Research Foundation of Korea.
(Schematic diagram of the research)
(From left: Bilirubin nanoparticles, cisplatin-chelated Bilirubin nanoparticles)
2017.09.26 View 8109 -
Draining Eyes Clogged with Glaucoma
Professor Gou Young Koh in the Graduate School of Medical Science and Engineering and his team have identified a new mechanism involved in the development and progression of glaucoma, and found a potential therapeutic option to treat it. Glaucoma is the second cause of irreversible blindness, after cataracts. It affects about 3.5% of the world population aged 40 to 80.
Professor Koh also serves as the director of the Center for Vascular Research at the Institute for Basic Science. The IBS said the study, published in the Journal of Clinical Investigation, is expected to help the development of therapies to treat primary open-angle glaucoma (POAG), which counts for three quarters of all glaucoma patients.
One of the most important risk factors for glaucoma is the increased pressure inside the eye. A liquid called aqueous humor is constantly produced and drained out from the eye. It transports nutrients and inflates the eye giving it a roughly spherical shape. However, if this fluid cannot flow out of the eye chambers freely, an increase in intraocular pressure can damage the optic nerve, leading to vision loss. The precise mechanism of elevated resistance to aqueous humor outflow remains unclear, and although the current treatments for glaucoma tackle the production and outflow of aqueous humor, their outcomes are still poor.
A component of the eye that plays a fundamental role in draining out the aqueous humor is Schlemm's canal. It collects the aqueous humor and mediates its transfer from the eye chambers to blood circulation. The cells on the walls of the canal, endothelial cells, ship the liquid from the inner to the outer side in “packages”, called vacuoles. As the shape and number of the vacuoles reflects the outflow performance, several giant vacuoles are expected in the normal outflow process.
The team explained how imbalances in Schlemm's canal significantly increase the risk of glaucoma. They showed that an important regulator for canal functionality is the angiopoietin-Tie2 system. Angiopoietins, such as Ang1 and Ang2, are proteins important for the growth of new blood vessels and Tie2 is the receptor that binds them. It is known that the angiopoietin-Tie2 system plays a role in Schlemm’s canal formation, as Tie2 mutations or angiopoietin absence result in congenital glaucoma. However, this study clarified that it is also critically important during adulthood.
The researchers reported that adult mice deficient in Tie2 suffer from an elevated intraocular pressure, retinal neuronal damage and partial visual impairment. Moreover, they had a markedly decreased number of giant vacuoles inside Schlemm’s canal endothelial cells, which indicate a poor aqueous humor drainage.
The scientists also investigated if and how this process changes in older mice, as aging is a major risk factor for glaucoma, and showed that aged mice experience reduced levels of giant vacuoles, Tie2, Ang1, and Ang2, as well as other proteins connected with the angiopoietin-Tie2 pathway, like Prox1.
To test whether Tie2 activation could shift the situation, the researchers tested the antibody ABTAA (Ang2-binding and Tie2-activating antibody). They injected it in one eye of mice, while the other eye of the same mice functioned as the negative control. After one week, levels of Tie2 and Prox1, number and diameter of giant vacuoles in Schlemm’s canals increased in the ABTAA-treated eyes compared to control eyes. The researchers observed a similar outcome with decreased intraocular pressure when ABTAA was injected to the eyes of mice suffering from POAG with regressed Schlemm’s canals, indicating that this antibody might be considered as a therapeutic option.
"Slow development of glaucoma treatments is partly due to the poor understanding of the underlying pathogenesis," said Professor Koh, the corresponding author of the study. "We hope that identifying the critical role of the angiopoietin-Tie2 system in adult Schlemm’s canals will bring a significant boost in the development of therapeutics."
Figure 1: Schlemm's canal position inside the eye.
Schlemm's canal (green) plays a fundamental role in draining the aqueous humor (white arrows) from the anterior chamber of the eye to blood circulation. If the aqueous humor is not able to flow out freely, elevated intraocular pressure damages the optical nerve causing glaucoma and eventually blindness.
Figure 2: Electron microscope images reveal how the aqueous humor is packaged in vacuoles (arrowheads) inside the cells forming the walls of Schlemm's canal.
Aging and glaucoma cause the number and size of giant vacuoles to decrease, meaning that the aqueous humor outflow is compromised. The images compare the giant vacuoles in Schlemm's canals of a healthy mouse (top) and a mouse lacking Tie2 (bottom)
Figure 3: The Ang2-binding and Tie2-activating antibody (ABTAA) rejuvenates the eye of aged mice and rescues them from glaucoma.
Aging causes a reduction of the protein Tie2, a risk factor for increased intraocular pressure and glaucoma. In this experiment, one eye of mice lacking Ang1 and Ang2 was injected with the premixed ABTAA and Ang2, while the other eye was used as negative control. The researchers observed an increase in the area of Schlemm’s canal, together with higher levels of Tie2 (red) and lower intraocular pressure, suggesting that ABTAA restores the canal's functionality. The image includes the transcription factor Prox1 (green) and CD144 (blue), a protein present at the junctions between cells that form the wall of the canal. The angiopoietin-Tie2 system and Prox1 are linked by a vicious circle: the less Tie2 and Ang2, the less Prox1, leading to Schlemm's canal damage, increase in intraocular pressure, and acceleration of glaucoma progression.
2017.09.19 View 6688 -
Semiconductor Patterning of Seven Nanometers Technology Using a Camera Flash
A research team led by Professor Sang Ouk Kim in the Department of Materials Science and Engineering at KAIST has developed semiconductor manufacturing technology using a camera flash.
This technology can manufacture ultra-fine patterns over a large area by irradiating a single flash with a seven-nanometer patterning technique for semiconductors. It can facilitate the manufacturing of highly efficient, integrated semiconductor devices in the future.
Technology for the Artificial Intelligence (AI), the Internet of Things (IoTs), and big data, which are the major keys for the fourth Industrial Revolution, require high-capacity, high-performance semiconductor devices. It is necessary to develop lithography technology to produce such next-generation, highly integrated semiconductor devices.
Although related industries have been using conventional photolithography for small patterns, this technique has limitations for forming a pattern of sub-10 nm patterns.
Molecular assembly patterning technology using polymers has been in the spotlight as the next generation technology to replace photolithography because it is inexpensive to produce and can easily form sub-10 nm patterns. However, since it generally takes a long time for heat treatment at high-temperature or toxic solvent vapor treatment, mass production is difficult and thus its commercialization has been limited.
The research team introduced a camera flash that instantly emits strong light to solve the issues of polymer molecular assembly patterning. Using a flash can possibly achieve a semiconductor patterning of seven nanometers within 15 milliseconds (1 millisecond = 1/1,000 second), which can generate a temperature of several hundred degrees Celsius in several tens of milliseconds.
The team has demonstrated that applying this technology to polymer molecular assembly allows a single flash of light to form molecular assembly patterns.
The team also identified its compatibility with polymer flexible substrates, which are impossible to process at high temperatures. Through these findings, the technology can be applied to the fabrication of next-generation, flexible semiconductors.
The researchers said the camera flash photo-thermal process will be introduced into molecular assembly technology and this highly-efficiency technology can accelerate the realization of molecular assembly semiconductor technology.
Professor Kim, who led the research, said, “Despite its potential, molecular assembly semiconductor technology has remained a big challenge in improving process efficiency.” “This technology will be a breakthrough for the practical use of molecular assembly-based semiconductors.”
The paper was published in the international journal, Advanced Materials on August 21 with first authors, researcher Hyeong Min Jin and PhD candidate Dae Yong Park.
The research, sponsored by the Ministry of Science and ICT, was co-led Professor by Keon Jae Lee in the Department of Materials Science and Engineering at KAIST, and Professor Kwang Ho Kim in the School of Materials Science and Engineering at Pusan National University.
(1. Formation of semiconductor patterns using a camera flash)
(Schematic diagram of molecular assembly pattern using a camera flash)
(Self-assembled patterns)
2017.09.18 View 10138