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Li Y.,USRA | Lenaghan S.C.,University of Tennessee at Knoxville | Zhang M.,University of Tennessee at Knoxville
Bulletin of Mathematical Biology | Year: 2012

The Venus flytrap has long been regarded as one of the most amazing examples of movement in the plant kingdom. The trapping ability of the flytrap consists of three unique features. First, trap closure represents one of the fastest movements in the plant kingdom. Second, a decision-making stage allows the plant to "decide" whether to completely close or open the trap, based on stimuli provided from the trapped object. Finally, the Venus flytrap contains a "memory function" that requires two mechanical stimuli within about 30 seconds to initiate trap closure. The movement involved in trap closure consists of nonlinear dynamics that have not been well understood. By understanding the movement, through nonlinear dynamics analysis, it will be possible to better understand this biological process. A mathematical model describing the movement of the Venus flytrap was first proposed by the authors in Yang et al., Plant Signal. Behav. 5(8), 968-978 (2010). In the current work, the earlier research has been advanced and an in-depth nonlinear and control analysis of the dynamic process has been provided. © 2012 Society for Mathematical Biology. Source

Agency: National Science Foundation | Branch: | Program: STTR | Phase: Phase I | Award Amount: 149.98K | Year: 2007

This Small Business Technology Transfer (STTR) Phase I project will experimentally validate the theory that inclusion of nanostructures within the Thermal Barrier Coatings (TBC) will enhance the resistance to hot corrosion by increasing the fracture strength of the ceramic thereby inhibiting grain growth similar to reinforcing concrete with rebar. The grain growth leads to the formation and growth of interconnected cracks needed for wicking of molten salts that result in spallation. The novel nanocomposite coating would find application within fossil energy power generation devices (dirty fuel) and aircraft engines (marine environments). Current technology turbine blades are comprised of single crystal nickel superalloys. Historically, protective TBC have allowed for operation of the turbine while subjected to hot gases exiting the combustor at temperatures exceeding the superalloy melting point. The increase in turbine inlet temperature has yielded improvements in efficiency, power density, and emission quality. However, these protective barriers are susceptible to hot corrosion, an electrochemical reaction between the superalloy and molten salts resulting in spallation or fragmentation of the thermal barrier coating. The reduction of premature spalling will allow for the simultaneous increase of the turbine inlet temperature and the reduction of the turbine coolant air. This combination has the potential to increase efficiency, reduce toxic emissions, and save capital costs.

George K.,Wyle | Chappell L.J.,USRA | Cucinotta F.A.,NASA
Mutation Research - Genetic Toxicology and Environmental Mutagenesis | Year: 2010

Cytogenetic damage was assessed in blood lymphocytes from 16 astronauts before and after they participated in long-duration space missions of 3 months or more. The frequency of chromosome damage was measured by fluorescence in situ hybridization (FISH) chromosome painting before flight and at various intervals from a few days to many months after return from the mission. For all individuals, the frequency of chromosome exchanges measured within a month of return from space was higher than their preflight yield. However, some individuals showed a temporal decline in chromosome damage with time after flight. Statistical analysis using combined data for all astronauts indicated a significant overall decreasing trend in total chromosome exchanges with time after flight, although this trend was not seen for all astronauts and the yield of chromosome damage in some individuals actually increased with time after flight. The decreasing trend in total exchanges was slightly more significant when statistical analysis was restricted to data collected more than 220 days after return from flight. When analysis was restricted to data collected within 220 days of return from the mission there was no relationship between total exchanges and time. Translocation yields varied more between astronauts and there was only a slight non-significant decrease with time after flight that was similar for both later and earlier sampling times. © 2010. Source

Li Y.,USRA | Cucinotta F.A.,NASA
Journal of Theoretical Biology | Year: 2011

Non-homologous end joining (NHEJ) is an important DNA repair pathway for DNA double-strand breaks. Several proteins, including Ku, DNA-PKcs, Artemis, XRCC4/Ligase IV and XLF, are involved in the NHEJ for the DNA damage detection, DNA free end processing and ligation. The classical model of NHEJ is a sequential model in which DNA-PKcs is first recruited by the Ku bound DNA prior to any other repair proteins. Recent experimental study (McElhinny et al., 2000; Costantini et al., 2007; Mari et al., 2006; Yano and Chen, 2008) suggested that the recruitment ordering is not crucial. In this work, by proposing a mathematical model in terms of biochemical reaction network and performing stability and related analysis, we demonstrate theoretically that if DSB repair pathway independent of DNA-PKcs exists, then the classical sequential model and new two-phase model are essentially indistinguishable in the sense that DSB can be repaired thoroughly in both models when the repair proteins are sufficient. © 2011. Source

Home > Press > Google Announces Results From Two Years of Testing on Quantum Computers Made by Harris & Harris Group Portfolio Company, D-Wave Systems Abstract: Harris & Harris Group, Inc. (NASDAQ: TINY), an investor in transformative companies enabled by disruptive science, notes that yesterday NASA, Google and the Universities Space Research Association (USRA) hosted a tour of the jointly run Quantum Artificial Intelligence Laboratory located at the NASA's Ames Research Center which houses one of D-Wave's 1,097-qubit D-Wave 2X™ quantum computers. At this event, Google announced that D-Wave's quantum computer was able to find solutions to complicated problems of nearly 1,000 variables up to 108 (100,000,000) times faster than classical computers. You may read Google's full discussion of these results at http://googleresearch.blogspot.ca/2015/12/when-can-quantum-annealing-win.html . We are also excited to note that Google's announcement was profiled in multiple articles published online following the event. The following link provides a list of such articles on Google's news search platform: https://news.google.com/news/story?ncl=dZiX84H9efiibMMsnNfEluViQM_dM&q=d-wave+systems&lr=English&hl=en&sa=X&ved=0ahUKEwiu4JDKhM7JAhVR5GMKHeqQDpcQqgIILDAB . About Harris & Harris Group Harris & Harris Group is a publicly traded venture capital firm that is also a business development company. Detailed information about Harris & Harris Group and its holdings can be found on its website at www.HHVC.com, on Facebook at www.facebook.com/harrisharrisvc and by following on Twitter @harrisandharrisgroup. This press release may contain statements of a forward-looking nature relating to future events. These forward-looking statements are subject to the inherent uncertainties in predicting future results and conditions. These statements reflect the Company's current beliefs, and a number of important factors could cause actual results to differ materially from those expressed in this press release. Please see the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2014, as well as subsequent filings, filed with the Securities and Exchange Commission for a more detailed discussion of the risks and uncertainties associated with the Company's business, including, but not limited to, the risks and uncertainties associated with venture capital investing and other significant factors that could affect the Company's actual results. Except as otherwise required by Federal securities laws, the Company undertakes no obligation to update or revise these forward-looking statements to reflect new events or uncertainties. The references and links to the websites www.HHVC.com, googleresearch.blogspot.ca, news.google.com, and www.Facebook.com have been provided as a convenience, and the information contained on such websites is not incorporated by reference into this press release. Harris & Harris Group is not responsible for the contents of third party websites. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

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