AR
-
Distinguished Professor Sang-Yup Lee received 2013 Amgen Biochemical Engineering Award
- Previous award winners are world-renowned scholars of biochemical engineering including James Bailey, Michael Shuler and Daniel Wang
KAIST Chemical and Biomolecular Engineering Department’s Professor Sang-Yup Lee has been selected to receive the 2013 Amgen Biochemical Engineering Award. The award ceremony will take place this June at the International Biochemical and Molecular Engineering conference in Beijing, China.
The Amgen Biochemical Engineering Award was established by Amgen, a world renowned American pharmaceutical company, in 1993. Amgen awards leading biochemical engineers every two years. The first Amgen award recipient was James Bailey of the California Institute of Technology (Caltech) in 1993. Since then leading engineers that are sometimes called “founding fathers of biochemical engineering” have received the award including MIT Professor Daniel Wang and Michael Shuler of Cornell University.
The first nine award winners were Americans and in 2011 Jens Nielson of Chalmers University of Technology, Sweden, received the Amgen award as a non-American. Professor Sang-Yup Lee is the first Asian to receive the award.
The Amgen award panel said, “Professor Lee made an incredible contribution to the fields of synthetic biology and industrial bioengineering by finding chemical material, fuel, protein and drug production and system bioengineering through metabolic engineering of microorganisms.”
Professor Lee is an expert in metabolic engineering of microorganisms and contributed to the development of system metabolic engineering and system bioengineering. Furthermore, he developed various medical and chemical products and processes which were then applied to synthesise strains of succinate, plastics, butanol and nylon.
Professor Lee is a fellow of the Korean Academy of Science and Technology and National Academy Engineering of Korea; an international member of National Academy of Engineering (US); a former fellow of the American Association for the Advancement of Science; a member of the American Institute of Chemical Engineers, the American Industrial Microbiology Society and American Academy of Microbiology. He is currently Head of Global Agenda Council on Biotechnology and is world renowned for his work in biotechnology field.
2013.04.30 View 8161 -
Popular Science May 2013: Online Electric Vehicle (OLEV) Introduced as Part of Smart Roads
Popular Science (PopSci), a famous American monthly magazine publishing popular science articles for general readers on science and technology subjects, introduced KAIST’s Online Electric Vehicle (OLEV) in its latest issue of May 2013. For the article, please see the attachment.
2013.04.25 View 7092 -
Award Winning Portable Sound Camera Design
- A member of KAIST’s faculty has won the “Red Dot Design Award,” one of three of the most prestigious design competitions in the world, for the portable sound camera.
KAIST’s Industrial Design Professor Suk-Hyung Bae’s portable sound camera design, made by SM Instruments and Hyundai, has received a “Red Dot Design Award: Product Design,” one of the most prestigious design competitions in the world.
If you are a driver, you must have experienced unexplained noises in your car. Most industrial products, including cars, may produce abnormal noises caused by an error in design or worn-out machinery. However, it is difficult to identify the exact location of the sound with ears alone.
This is where the sound camera comes in. Just as thermal detector cameras show the distribution of temperature, sound cameras use a microphone arrangement to express the distribution of sound and to find the location of the sound. However, existing sound cameras are not only too big and heavy, their assembly and installation are complex and must be fixed on a tripod. These limitations made it impossible to measure noises from small areas or the base of cars.
The newly developed product is an all-in-one system resolving the inconvenience of assembling the microphone before taking measurements. Moreover, the handle in the middle is ergonomically designed so users can balance its weight with one hand. The two handles on the sides work as a support and enable the user to hold the camera in various ways.
At the award ceremony, Professor Suk-Hyung Bae commented, “The effective combination of cutting edge technology and design components has been recognized.” He also said, “It shows the competency of the KAIST’s Department of Industrial Design, which has a high understanding of science and technology.”
On the other hand, SM Instruments is a sound vibration specialist company which got its start from KAIST’s Technology Business Incubation Centre in 2006 and earned its independence by gaining proprietary technology in only two years. SM Instruments is contributing to developing national sound and vibration technology through relentless change and innovation. ;
Figure 1: Red Dot Design Award winning the portable sound camera, SeeSV-S205
Figure 2: Identifying the location of the noise using the portable sound camera
Figure 3: The image showing the sound distribution using the portable sound camera
2013.04.09 View 19007 -
The new era of personalized cancer diagnosis and treatment
Professor Tae-Young Yoon
- Succeeded in observing carcinogenic protein at the molecular level
- “Paved the way to customized cancer treatment through accurate analysis of carcinogenic protein”
The joint KAIST research team of Professor Tae Young Yoon of the Department of Physics and Professor Won Do Huh of the Department of Biological Sciences have developed the technology to monitor characteristics of carcinogenic protein in cancer tissue – for the first time in the world.
The technology makes it possible to analyse the mechanism of cancer development through a small amount of carcinogenic protein from a cancer patient. Therefore, a personalised approach to diagnosis and treatment using the knowledge of the specific mechanism of cancer development in the patient may be possible in the future.
Until recently, modern medicine could only speculate on the cause of cancer through statistics. Although developed countries, such as the United States, are known to use a large sequencing technology that analyses the patient’s DNA, identification of the interactions between proteins responsible for causing cancer remained an unanswered question for a long time in medicine.
Firstly, Professor Yoon’s research team has developed a fluorescent microscope that can observe even a single molecule. Then, the “Immunoprecipitation method”, a technology to extract a specific protein exploiting the high affinity between antigens and antibodies was developed. Using this technology and the microscope, “Real-Time Single Molecule co-Immunoprecipitation Method” was created. In this way, the team succeeded in observing the interactions between carcinogenic and other proteins at a molecular level, in real time.
To validate the developed technology, the team investigated Ras, a carcinogenic protein; its mutation statistically is known to cause around 30% of cancers.
The experimental results confirmed that 30-50% of Ras protein was expressed in mouse tumour and human cancer cells. In normal cells, less than 5% of Ras protein was expressed. Thus, the experiment showed that unusual increase in activation of Ras protein induces cancer.
The increase in the ratio of active Ras protein can be inferred from existing research data but the measurement of specific numerical data has never been done before.
The team suggested a new molecular level diagnosis technique of identifying the progress of cancer in patients through measuring the percentage of activated carcinogenic protein in cancer tissue.
Professor Yoon Tae-young said, “This newly developed technology does not require a separate procedure of protein expression or refining, hence the existing proteins in real biological tissues or cancer cells can be observed directly.” He also said, “Since carcinogenic protein can be analyzed accurately, it has opened up the path to customized cancer treatment in the future.”
“Since the observation is possible on a molecular level, the technology confers the advantage that researchers can carry out various examinations on a small sample of the cancer patient.” He added, “The clinical trial will start in December 2012 and in a few years customized cancer diagnosis and treatment will be possible.”
Meanwhile, the research has been published in Nature Communications (February 19). Many researchers from various fields have participated, regardless of the differences in their speciality, and successfully produced interdisciplinary research. Professor Tae Young Yoon of the Department of Physics and Professors Dae Sik Lim and Won Do Huh of Biological Sciences at KAIST, and Professor Chang Bong Hyun of Computational Science of KIAS contributed to developing the technique.
Figure 1: Schematic diagram of observed interactions at the molecular level in real time using fluorescent microscope. The carcinogenic protein from a mouse tumour is fixed on the microchip, and its molecular characteristics are observed live.
Figure 2: Molecular interaction data using a molecular level fluorescent microscope. A signal in the form of spike is shown when two proteins combine. This is monitored live using an Electron Multiplying Charge Coupled Device (EMCCD). It shows signal results in bright dots.
An organism has an immune system as a defence mechanism to foreign intruders. The immune system is activated when unwanted pathogens or foreign protein are in the body. Antibodies form in recognition of the specific antigen to protect itself. Organisms evolved to form antibodies with high specificity to a certain antigen. Antibodies only react to its complementary antigens. The field of molecular biology uses the affinity between antigens and antibodies to extract specific proteins; a technology called immunoprecipitation. Even in a mixture of many proteins, the protein sought can be extracted using antibodies. Thus immunoprecipitation is widely used to detect pathogens or to extract specific proteins.
Technology co-IP is a well-known example that uses immunoprecipitation. The research on interactions between proteins uses co-IP in general. The basis of fixing the antigen on the antibody to extract antigen protein is the same as immunoprecipitation. Then, researchers inject and observe its reaction with the partner protein to observe the interactions and precipitate the antibodies. If the reaction occurs, the partner protein will be found with the antibodies in the precipitations. If not, then the partner protein will not be found. This shows that the two proteins interact.
However, the traditional co-IP can be used to infer the interactions between the two proteins although the information of the dynamics on how the reaction occurs is lost. To overcome these shortcomings, the Real-Time Single Molecule co-IP Method enables observation on individual protein level in real time. Therefore, the significance of the new technique is in making observation of interactions more direct and quantitative.
Additional Figure 1: Comparison between Conventional co-IP and Real-Time Single Molecule co-IP
2013.04.01 View 17173 -
KAIST and Saudi Aramco agreed to establish a joint CO2 research center in Korea
The Korea Advanced Institute of Science and Technology (KAIST) and Saudi Aramco, a global energy and petrochemicals enterprise, signed a memorandum of understanding (MOU) on January 6, 2013 in Dhahran, Saudi Arabia and pledged to jointly collaborate in research and development of innovative technologies and solutions to address the world"s energy challenges.
Under the MOU, the two entities agreed to establish a research center, Saudi Aramco-KAIST CO2 Research Center, near KAIST"s main campus in Daejeon, Korea. The research center, to be jointly managed by KAIST and Saudi Aramco, will foster and facilitate research collaborations in areas such as tackling carbon dioxide (CO2) emissions by removal or capture of CO2, conversing CO2 into useful products, developing efficiency improvements in energy production, sharing carbon management technologies, establishing exchange programs, and conducting joint projects.
According to Saudi Aramco, the company"s collaboration with KAIST is the first partnership established in Asia. Khalid A. Al-Falih, President and CEO of Saudi Aramco, said,
"The CO2 Research Center represents a major step in Saudi Aramco"s research and technology strategy to partner with top global institutions to help address and find sustainable solutions to the world’s energy challenge both domestically and internationally."
2013.03.19 View 9144 -
An efficient strategy for developing microbial cell factories by employing synthetic small regulatory RNAs
A new metabolic engineering tool that allows fine control of gene expression level by employing synthetic small regulatory RNAs was developed to efficiently construct microbial cell factories producing desired chemicals and materials
Biotechnologists have been working hard to address the climate change and limited fossil resource issues through the development of sustainable processes for the production of chemicals, fuels and materials from renewable non-food biomass. One promising sustainable technology is the use of microbial cell factories for the efficient production of desired chemicals and materials. When microorganisms are isolated from nature, the performance in producing our desired product is rather poor. That is why metabolic engineering is performed to improve the metabolic and cellular characteristics to achieve enhanced production of desired product at high yield and productivity. Since the performance of microbial cell factory is very important in lowering the overall production cost of the bioprocess, many different strategies and tools have been developed for the metabolic engineering of microorganisms.
One of the big challenges in metabolic engineering is to find the best platform organism and to find those genes to be engineered so as to maximize the production efficiency of the desired chemical. Even Escherichia coli, the most widely utilized simple microorganism, has thousands of genes, the expression of which is highly regulated and interconnected to finely control cellular and metabolic activities. Thus, the complexity of cellular genetic interactions is beyond our intuition and thus it is very difficult to find effective target genes to engineer. Together with gene amplification strategy, gene knockout strategy has been an essential tool in metabolic engineering to redirect the pathway fluxes toward our desired product formation. However, experiment to engineer many genes can be rather difficult due to the time and effort required; for example, gene deletion experiment can take a few weeks depending on the microorganisms. Furthermore, as certain genes are essential or play important roles for the survival of a microorganism, gene knockout experiments cannot be performed. Even worse, there are many different microbial strains one can employ. There are more than 50 different E. coli strains that metabolic engineer can consider to use. Since gene knockout experiment is hard-coded (that is, one should repeat the gene knockout experiments for each strain), the result cannot be easily transferred from one strain to another.
A paper published in Nature Biotechnology online today addresses this issue and suggests a new strategy for identifying gene targets to be knocked out or knocked down through the use of synthetic small RNA. A Korean research team led by Distinguished Professor Sang Yup Lee at the Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), a prestigeous science and engineering university in Korea reported that synthetic small RNA can be employed for finely controlling the expression levels of multiple genes at the translation level. Already well-known for their systems metabolic engineering strategies, Professor Lee’s team added one more strategy to efficiently develop microbial cell factories for the production of chemicals and materials.
Gene expression works like this: the hard-coded blueprint (DNA) is transcribed into messenger RNA (mRNA), and the coding information in mRNA is read to produce protein by ribosomes. Conventional genetic engineering approaches have often targeted modification of the blueprint itself (DNA) to alter organism’s physiological characteristics. Again, engineering the blueprint itself takes much time and effort, and in addition, the results obtained cannot be transferred to another organism without repeating the whole set of experiments. This is why Professor Lee and his colleagues aimed at controlling the gene expression level at the translation stage through the use of synthetic small RNA. They created novel RNAs that can regulate the translation of multiple messenger RNAs (mRNA), and consequently varying the expression levels of multiple genes at the same time. Briefly, synthetic regulatory RNAs interrupt gene expression process from DNA to protein by destroying the messenger RNAs to different yet controllable extents. The advantages of taking this strategy of employing synthetic small regulatory RNAs include simple, easy and high-throughput identification of gene knockout or knockdown targets, fine control of gene expression levels, transferability to many different host strains, and possibility of identifying those gene targets that are essential.
As proof-of-concept demonstration of the usefulness of this strategy, Professor Lee and his colleagues applied it to develop engineered E. coli strains capable of producing an aromatic amino acid tyrosine, which is used for stress symptom relief, food supplements, and precursor for many drugs. They examined a large number of genes in multiple E. coli strains, and developed a highly efficient tyrosine producer. Also, they were able to show that this strategy can be employed to an already metabolically engineered E. coli strain for further improvement by demonstrating the development of highly efficient producer of cadaverine, an important platform chemical for nylon in the chemical industry.
This new strategy, being simple yet very powerful for systems metabolic engineering, is thus expected to facilitate the efficient development of microbial cell factories capable of producing chemicals, fuels and materials from renewable biomass.
Source: Dokyun Na, Seung Min Yoo, Hannah Chung, Hyegwon Park, Jin Hwan Park, and Sang Yup Lee, “Metabolic engineering of Escherichia coli using synthetic small regulatory RNAs”, Nature Biotechnology, doi:10.1038/nbt.2461 (2013)
2013.03.19 View 9321
-
KAIST Develops Wireless Power Transfer Technology for High Capacity Transit
KAIST and the Korea Railroad Research Institute (KRRI) have developed a wireless power transfer technology that can be applied to high capacity transportation systems such as railways, harbor freight, and airport transportation and logistics. The technology supplies 60 kHz and 180 kW of power remotely to transport vehicles at a stable, constant rate.
KAIST and KRRI successfully showcased the wireless power transfer technology to the public on February 13, 2013 by testing it on the railroad tracks at Osong Station in Korea. Originally, this technology was developed as part of an electric vehicle system introduced by KAIST in 2011 known as the On-line Electric Vehicle (OLEV).
OLEV does not need to be parked at a charging station to have a fully powered battery. It gets charged while running, idling, and parking, enabling a reduction in size of the reserve battery down to one-fifth of the battery on board a regular electric car. The initial models of OLEV, a bus and a tram, receive 20 kHz and 100 kW power at an 85% transmission efficiency rate while maintaining a 20cm air gap between the underbody of vehicle and the road surface. OLEV complies with the national and international standards of 62.5 mG, a safety net for electromagnetic fields. In July 2013, for the first time since its development, OLEV will run on a regular road, an inner city route in the city of Gumi, requiring 40 minutes of driving each way.
Today’s technology demonstration offers further support that OLEV can be utilized for large-scale systems. Professor Dong-Ho Cho, Director of Center for Wireless Power Transfer Technology Business Development at KAIST, explained the recent improvements to OLEV:
“We have greatly improved the OLEV technology from the early development stage by increasing its power transmission density by more than three times. The size and weight of the power pickup modules have been reduced as well. We were able to cut down the production costs for major OLEV components, the power supply, and the pickup system, and in turn, OLEV is one step closer to being commercialized.”
If trains receive power wirelessly, the costs of railway wear and tear will be dramatically reduced. There will be no power rails, including electrical poles, required for the establishment of a railway system, and accordingly, lesser space will be needed. Tunnels will be built on a smaller scale, lowering construction costs. In addition, it will be helpful to overcome major obstacles that discourage the construction of high speed railway systems such as noise levels and problems in connecting pantograph and power rails.
KAIST and KRRI plan to apply the wireless power transfer technology to trams in May and high speed trains in September.
2013.03.19 View 11968 -
Launched the Saudi Aramco-KAIST CO2 Management Center in Korea
KAIST and Saudi Aramco, a global energy and petrochemicals enterprise, signed on February 20, 2013 the Master Research and Collaboration Agreement (the Agreement) on joint collaborations in research and development of carbon management between the two entities.
The Agreement was subsequently concluded upon the signing of the Memorandum of Understanding (MOU) between KAIST and Saudi Aramco, dated January 7th, 2013. In the Agreement, the two organizations specified terms and conditions necessary to conduct joint research projects and stipulated governing body for the operation of the Saudi Aramco-KAIST CO2 Management Center.
KAIST and Saudi Aramco, a national oil company for Saudi Arabia, entered into the MOU, in which the two parties shared a common interest in addressing the issue of CO2 capture, CO2storage, CO2 avoidance using efficiency improvements, and converting CO2 into useful chemicals and other materials, and agreed to “create a major research center for CO2” in Korea.
As envisioned by the MOU and its subsequent agreement, KAIST and Saudi Aramco decided to operate an interim office of the Saudi Aramco-KAIST CO2 Management Center at KAIST campus in Daejeon, Korea, pending the establishment of the research center. The full-fledged, independent research facility will be built at a location and during a period to be agreed between the two parties.
Following the signing of the Agreement, there was a celebration event taken place, including a signboard hanging ceremony for the interim research office. A 10-member delegation from Saudi Aramco, which was headed by Vice President of Engineering Services Samir Al-Tubayyeb, Dr. Nam-Pyo Suh, former president of KAIST, Vice President of Research at KAIST Kyung-Wook Paik, and senior representatives from Korean oil and petrochemical companies such as S-Oil, Lotte Chemicals, SK Innovation, and STX attended the event.
Kyung-Wook Paik, Vice President of Research at KAIST, said,
“In order to help find solutions to carbon management, KAIST and Saudi Aramco will facilitate to exchange each party’s complementary technical expertise, gain insight into new research fields, and have access to key sources of talent, while promoting innovation for technology solutions and contributing to the lifelong learning agenda of both organizations.”
Samir Al-Tubayyeb, Vice President of Engineering Services at Saudi Aramco, added that “As a world-leading oil and gas company, Saudi Aramco’s mission is to promote the continued use of safe, environmentally-friendly petroleum products with a vision to becoming a global leader in research and technology. Building a strong and cooperative relationship with KAIST in our endeavor to search for alternative ways to better utilization of fossil fuels will expedite the creation of opportunities to make the world environmentally safer and sustainable.”
KAIST and Saudi Aramco will each chip in a maximum of USD 5 million annually for the establishment and operation of the Saudi Aramco-KAIST CO2 Management Center during the initial term of the Master Research and Collaboration Agreement, which starts in 2013 and continues through 2018.
2013.03.19 View 13018 -
Op-Ed by Professor David Helfman: Global Science and Education in Korea for the 21st Century
Professor David Helfman from the Department of Biological Sciences and Graduate School of Nanoscience and Technology contributed an op-ed, “Global Science and Education in Korea for the 21st Century, to the Korea Herald on February 20, 2013. For the article, please click the link below:
http://www.koreaherald.com/view.php?ud=20130220000623.
2013.02.26 View 9381
-
Synthesis of a New Organic Supermolecule Succeeded
From left to right: Prof.Stoddart, Prof.Goddard and Prof.Jang Wook Choi
KAIST EEWS graduate school’s research team led by Prof. Stoddart, Prof. Goddard and Prof. Jang Wook Choi has succeeded the synthesis of a new organic supermolecule that is stable in a radical condition under room temperature.
Prof. Stoddart, who mainly led this research, is the world’s great scholar on orgaic molecular structure especially on catenane with an interconnection of several ring structures. Catenane is originated from Latin “catenane” referring to “chain”. The brief structure of the synthesized catenane is as following:
Usually radicals are known to be unstable since they are electronically neutral and have very high reactivity. However, the radicals from this research showed air- and water- stability. It also showed a reversible change in oxidation number from o to +8 through chemical/electrochemical oxidation-reduction reaction. The phenomenon where paramagnetic and diamagnetic characteristics change according to the oxidation number has also been observed.
Thus, the research like this - on the molecules showing various characteristics with stable radical - is expected to give a new direction to the next-generation electromemory system, semiconductor and energy storage system research.
Meanwhile, this research, led by Prof.Stoddart team with Prof.Goddard and Prof. Jang Wook Choi’s team, is conducted under the support of Science and Technology’s World Class University project by Ministry of Education and published in ‘Science’ on 25th of Jan.
2013.02.24 View 9951
-
A Substance with Amazingly Improved Efficiency of Capturing Carbon Dioxides Developed
From left to right: Prof.Ali Coskun, Prof. Cafer T. Yavuz and Prof. Yousung Jung
- Selectivity of CO2 increased by 300 times in comparison to nitrogen, published in Nature Communications-
KAIST EEWS graduate school’s joint research team led by Prof. Cafer T. Yavuz, Prof. Ali Coskun, and Prof. Yousung Jung has developed the world"s most efficient CO2 absorbent that has 300 times higher carbon dioxide selectivity in comparison to nitrogen.
Recently, the importance of CCS* technology, which is about capturing, storing and treating carbon dioxides, has begun to emerge world-widely as a practical alternative for the response to climate change.
* CCS : Carbon Capture and sequestration
Current carbon dioxide capturing technologies are wet capturing using liquid absorbent, dry capturing using solid absorbent and separation-membrane capturing using a thin membrane like a film.
For the places like power plant and forge, where the emission of carbon dioxides is huge, the main task is to maintain the capturing efficiency under extremely hot and humid conditions.
The previously studied dry absorbents, such as MOF or zeolite, had the disadvantages of instability in moist conditions and expensive cost for synthesis.
On the other hand, the research team"s newly discovered dry absorbent, named ‘Azo-COP’, can be synthesized without any expensive catalysts so the production cost is very low. It is also stable under hot and humid conditions.
COP is a structure consisting of simple organic molecules combined into porous polymer and is the first dry carbon dioxide capturing material developed by this research team.
The research team introduced an additional functional group called "Azo" to the substance, so that it can selectively capture carbon dioxides among the mixture of gas.
Azo-COP, which includes ‘Azo’ functional group, is manufactured easily by using common synthesis methods, and impurities are removed simply by using cheap solvents like water and acetone instead of expensive catalysts. As a result, the manufacturing cost has lowered drastically.
Especially, Azo-COP is combined with carbon dioxides by weak attraction force rather than chemical attraction so the recycling energy cost for the absorbent can be reduced innovatively, and it is expected to be used for capturing substances other than carbon dioxides in various areas as it is stable under extreme conditions even under 350 degrees Celsius.
This research is supported by Korea Carbon Capture&Sequestration R&D Center(Head: Sangdo Park) and KAIST EEWS planning group.
Prof. Cafer T. Yavuz and Prof. Ali Coskun said that “when Azo-COP is used for separation of CO2 and N2, the capturing efficiency has increased by hundred times.” He continued “This substance does not need any catalysts and has great chemical characteristics like water stability and structure stability so is expected to be used in various fields including carbon dioxides capturing”
Meanwhile, this research is published in ‘Nature’s stablemate ‘Nature Communications’ on 15th of Jan.
2013.02.24 View 11464
-
Professor Shin In Shik First in Asia to receive Excellent Dissertation Award from IEEE RTSS
The research team lead by Professor Shin In Shik (Department of Computer Science) received the Excellent Dissertation Awardy in the IEEE RTSS out of 157 dissertations.
It is the first time a Professor under an institute in the Asia region received the Award in the RTSS field during its 33 year history.
Professor Shin had already received an Excellent Dissertation Award as a Ph.D. candidate at the University of Pennsylvania. Thus Professor Shin became the first and only scientist to receive the Award twice.
Professor Shin has successfully defined the scheduling method of the multicore processor which was regarded as the problem in the field of RTSS for the past decade.
Professor Shin has suggested new criteria for sorting real time tasks in parallel thereby suggesting a new scheduling method that surpasses current scheduling methods. The results are anticipated to provide new perspectives in the field of RTSS using multicore processors.
2013.01.22 View 7764